The URL can be used to link to this page

16-103450Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Section Page ExecutiveSummary...........................................................................................................................................................................2 Section1- Project Overview.........................................................................................................................................................4 1. TIR Worksheet.......................................................................................................................................................................4 2. Site Location..........................................................................................................................................................................9 3. Drainage Basins, Site Characteristics, and Sub basins.........................................................................................10 4. Soils ............... ............ —........ .................... ....... ....................................................................................................................... 12 Section 2- Conditions and Requirements Summary......................................................................................................13 Section3- Offsite Analysis..........................................................................................................................................................17 1. Upstream Analysis.............................................................................................................................................................17 2. Downstream Analysis.......................................................................................................................................... 17 3. Evidence of Existing or Predicted Problems............................................................................................................17 Section 4- Flow Control and Water Quality Facility Analysis and Design ...... .......................... —......:.............. 18 1. Hydrologic Analysis .............................. —....... ............ ............................................................................... ,................18 2. Existing Site Hydrology...................................................................................................................................................18 3. Developed Site Hydrology.............................................................................................................................................19 4. Performance Standards...................................................................................................................................................19 5. Flow Control Analysis.......................................................................................................................................................19 6. Water Quality System.......................................................................................................................................................19 Section 5- Conveyance System Analysis and Design....................................................................................................20 1. Conveyance..........................................................................................................................................................................20 2. 100 Year Flood/Overflow Condition..........................................................................................................................20 Section6- Special Reports and Studies................................................................................................................................21 Section7- Other Permits..........................................................................................................................................................22 Section 8- CSWPPP Analysis and Design.............................................................................................................................23 Section 9- Bond Quantities, Facility Summaries, and Declaration of Covenant.............................................25 Section 10- Operations and Maintenance Manual.........................................................................................................26 Appendices: A — Exhibits B — Design Calculations C — Geotechnical Engineering Report D — Water Quality Information r fll.. L/"11 V V rrojeci v lu--)iauu4 Page 1 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Site Location: The subject site is located at the northeast corner of Pacific Highway South and South 336th Street. The site is bordered by a Motel to the north, single family residential to the east, Pacific Highway to the west, and 336th Street to the south. The site is currently developed and occupied by a +/- 5,000 sf Columbia Bank building. The balance of the site is comprised of parking lot and landscaped areas. This project proposes to demolish the existing Columbia Bank building and construction of a new 6,900 sf Advance Auto Parts Store, landscaping, and parking on the 1.82- acre site. Design Criteria: The City of Federal Way uses the King County Surface Water Management Design Manual (KCSWDM), 2016 Edition, as adopted by the City of Federal. The existing site is developed and covered by impervious surfaces (building & pavement), with the exception of minor perimeter and parking lot landscaping. In addition to the improved areas of the site there is a large tract of native vegetation nearly 65' wide running along the entire length of the East property line. The proposed construction will match existing site conditions pertaining to land cover types (i.e., impervious and pervious). The project proposes at least 7,000 sf of land disturbing activing and is a redevelopment project on a single parcel site in which the total of new plus replaced impervious surface is 5,000 and whose valuation of proposed improvements exceeds 50% of the assessed value of the existing site improvements. Therefore, this project is subject to a Full Drainage Review as required by the City of Federal Way. As a result, all 8 Core Requirements and 5 Special Requirements of the KCSWDM will apply to this site. Table 1— Jurisdictional Requirements below describes the requirements set forth in the 2016 KCSWDM. Table 1 PACLAN D Peak Runoff Control: Spill Jurisdictional Requirements Conservation Flow Control Area Level 2 Flow Control Provide if discharging off -site or into a natural onsite Control: I drainage feature Water I Enhanced Basic Water Quality Treatment: Quality: -50% of developed 2-year peak flow rate -80% removal of TSS Stormfilter Cartridges (ZPG & CSF treatment train) 35% of the developed 2-year peak flow rate Project # 10518004 Page 2 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington �i Proposed Drainage System: The project proposes to install new storm water facilities for conveyance and water quality treatment. The majority of the site is to be regraded to accommodate the new building configuration, parking layout, and facilitate stormwater surface flow to the existing/proposed storm water system. All stormwater runoff for the site will be collected within catch basins strategically placed throughout the site at low points and conveyed through a new underground stormwater system to a proposed Stormfilter (ZPG) manhole where it is collected and then conveyed to a proposed Stormfilter (CSF) manhole for water treatment before discharging to the existing storm water conveyance system located south of the site within South 336th Street. The subject site lies within the Conservation Flow Control Area (Level 2 flow control standard). The proposed redevelopment project exceeds the 5,000 sf threshold for new and/or replaced impervious surface, however per exception 2, listed in Section 1.2.3-13 of the KCSWDM, the project is exempt from flow control requirements as the redeveloped site will not increase the 100-year peak flow by more than 0.1 cfs. This provision applies to existing (NOT historic) conditions. Therefore, no flow control facilities are proposed as part of this project. Conclusion: The proposed stormwater management system for this project has been designed in accordance with regulatory criteria described above and is consistent with sound engineering practice. The site has been analyzed to determine the requirements for water quality treatment, and no significant adverse impacts to the stormwater management system are expected as a result of the proposed development. `1 PACLAND Project # 10518004 Page 3 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington OverviewSection I- Project Figure 1 - Technical Information Worksheet (KCSWDM 2016) KING COUN I'Y, WASH INGTON', SURFACE WATER tnESIGIN' MAN' UAI TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 1 PROJECT OWNER AND PROJECT ENGINEER Project Owner Cadence Capital Investments LLC Phone (425) 270-9782 Address 4580 Klahanie Dr. SE Issaquah, WA 98029 Project Engineer Sean Mallon. PE Company PACLAND - Seattle Phone (206) 522-9510 Part3 TYPE OF PERMIT APPLICATION ❑ Landuse Services Subdivison / Short Subd. / UPD ® Building Services MIF / Commerical / SFR ❑ Clearing and Grading ❑ Right -of -Way Use ❑ Other Part 5 PLAN AND REPORT INFORMATION Technical Information Report Type of Drainage Review Full ! Targeted I (circle): Large Site Date (include revision dates): Date or Final: Part2 PROJECT LOCATION AND DESCRIPTION Project Name Advance Auto Parts DDES Permit# Location Township 21 N Range 04 E Section 16 Site Address 33370 Pacific HighwaYS Part4 OTHER REVIEWS AND PERMITS ❑ DFW HPA ❑ Shoreline ❑ COE 404 Management ❑ DOE Dam Safety ❑ Structural RockeryfVautU ❑ FEMA Floodplain ❑ ESA Section 7 ❑ COE Wetlands ❑ Other Site Improvement Plan (Eng►. Plans) Type (circle one): Fuli / Modified ! mall Site Date (include revision dates): Date of Final: Part 6 ADJUSTMENT APPROVALS Type (circle one): Standard / Complex / Preapplicabon I Experimental / Blanket Description: (include conditions in TIR Section 2) Date of Approval; 2001) SiLfau WV tter Design iMamral I PACLAND Project # 10518004 Page 4 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington KING COUNTY, WASHING10N. SURFACE XVATFR nF.SiGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 7 MONITORING REQUIREMENTS Monitoring Required: Yes No Describe: Start Date: Completion Date: PartS SITE COMMUNITY AND DRAINAGE BASIN Community Plan : Community Business Spersal Dislnct Overlays: Drainage Basin: H flebos Creek & Lower Ppet Sound Basin Stormwater Requirements: Enhanced WQ Treatment 5 ill Control Part 9 ONSITE AND ADJACENT SENSITIVE AREAS River/Stream ❑ Steep Slope ❑ Lake ❑ Erosion Hazard Wetlands ❑ Landslide Hazard Closed Depression ❑ Coal Mine Hazard Floodplain ❑ Seismic Hazard Other ❑ Habitat Protection Part 10 SOILS -Pub Erosion Potential Qvr-Recessional Average - 7% Low outwash deposits High Groundwater Table (within 5 feet) ❑ Sole Source Aquifer Other ❑ Seeps &prangs i 2009 Surfa.-c Watcr 17csign A9:umal 2 1 4,'2004 PACLAND Project # 10518004 Page 5 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington KING COUNTY, WAMIINGTON, SIJRGACL• WATER [)kSIGN AIANLIAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part11 DRAINAGE DESIGN LIMITATIONS j REFERENCE u Cere 2 -Off irP A al is ❑ Sensitive�Critical Araas ❑ SEPA ❑ ther Additional Sheets Attached LIMITATION / SITE CONSTRAINT Nane known 2009 Surface Watcrrlcsigu A9anua1 I t9; 2U09 PACLAND Project # 10518004 Page 6 Advance Auto Parts site. Preliminary Technical Information Report Federal Way, Washington KING COUNTY, WASHINGTON, SURFACE WATER DI?SIG\ NIASUA1 TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Control Treatment BMP: Maintenance Agreement: Yes No unri...,ti--. A Stormfilter CB (ZPG) followed by a Stormfilter MH (CSF) will provide enhanced WO treatment for the subject MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION ® Clearing Limits ® Cover Measures ® Perimeter Protection ® Traffic Area Stabilization ® Sediment Retention ® Surface Water Collection ® Dewatering Control ® Dust Control ❑ Flow C'nnlrnt MINIMUM ESC REQUIREMENTS AFTER CONSTRUCTION Stabilize Exposed Surfaces Remove and Restore Temporary ESC Fa6iilies Clean and Remove All Silt and Debris, Ensure Operation of permanent Fatalities ❑ Flag Limits of SAO and open space Preservation areas ❑ Other Part 14 STORMWATEIR FACILITY DESCRIPTIONS Note: Include Facili SUrrtma and Sketch Flow Control I T MDescri lion Water Ouati! 7 lE7esai lion ❑ Detention ❑ Biofiltration ❑ Infiltration ❑ Wetpool ❑ Regional Facility ® Media Filtration _ ❑ Shared Facility -SiotrnlilLeLCB-uL H ❑ Oil Control (ZPG & CSF) 2 ❑ Flow Control r I ❑Spill Control BMPs ❑ Other ❑ Flow Control BMPs ❑ Other 2009 Surface Water Design Manual 4 1."()!2009 PACLAND Project # 10518004 Page 7 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington KING CC)t NTy. WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 15 EASEMENTS/TRACTS Drainage Easement Covenant Native Growth Protection Covenant ❑ Tract Other Part 16 STRUCTURAL ANALYSIS LJ Cast in Place Vault ® Retaining Wall ❑ Rockery > 4' High ❑ Structural on Steep Slope ❑ Other Part 17 SIGNATURE OF PROFESSIONAL ENGINEER 1, or a civil engineer under my supervision, have visited the site. Actual site conditions as observed were incorporated into this worksheet and the attached Technical Information Report. To the best of my knawiedge the snlormation pr*vided here is accurate, 2009 Surface Water Dcsign Manual PACLAND 5 Project # 10518004 1 /912009 Page 8 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington _ N . mteprnpran f i.� - =_.SId ji ~fG74raf ',VAV +T SITE ,ice G � Q ki t is ry CIl•rl er S 343rd Sc LO Q, S 347th P1 Figure 2 - Site Location Location: 1804 S. 336th Street 33370 Pacific Highway S. Section/Township/Range: Sec. 16, T. 21 N, R. 4 E Parcel/Tax Lot(s): 797820-0050 & 797820-0060 Size: 1.824 acres City, County, State: Federal Way, King County, Washington Governing Agency: City of Federal Way Design Criteria: 2016 King County Surface Water Design Manual (KCSWDM) PACLAND Project # 10518004 Page 9 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Drainage Basins, Subbasins, and Site Characteristics Draina a Basin The project site lies within the Hylebos Creek Basin, which is part of the Puyallup River Watershed. Existin Subbasins The project site has one existing basin comprised of the entirety of the impervious area on site. Surface runoff within the basin is collected within multiple existing catch basin inlets before discharging into the storm main located under South 336th Street. See Exhibit 1 in Appendix A for a depiction of the existing basin. Proposed Subbasins The resulting redeveloped site will be one basin comprised of the entire site area. On -Site surface runoff from impervious areas will convey to a series of catch basin positioned around the site and connected via a new underground conveyance system, which in turn convey to a proposed Stormfilter (ZPG) catch basin where it is collected and then conveyed to a proposed Stormfilter (CSF) manhole for water treatment immediately before discharging to the stormwater main in South 336th Street. See Exhibit 2 in Appendix A for a depiction of the proposed sub basins A and B. Table 2 — Site Areas Existi Surface n Area (SF) Pro aced Area Roof 4,792 6,970 Landscaping (Pervious) 36,590 36,590 Pavement (PGIS) 37,897 35,719 Total f 79,279 79,279 Site Characteristics The subject site is located at the northeast corner of Pacific Highway South and South 336th Street. the site is bordered by a Motel to the north, single family residential to the east, Pacific Highway to the west to, and 336th Street to the south. The site is currently developed and occupied by a +/- 5,000 sf Columbia Bank building. The balance of the site is comprised of parking lot and landscaped areas. This project proposes to demolish the existing Columbia Bank building and construction of a new 6,900 sf Advance Auto Parts Store, landscaping, and parking on the 1.82-acre site. The amount of pervious area on site will remain the same with the area changes coming from an increase in impervious roof area and a decrease in pollution generating impervious surface. PACLAND Project # 10518004 Page 10 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington soils A Geotechnical Engineering Report for the subject site is located in Appendix C. Figure 3 Site Soils (USGS Scientific Investigations Map 2854) al I. . 1 !TE I The site is mapped as Recessional outwash deposits (Qvr) according to USGS Scientific Investigations Map 2854 Geologic Map of the Poverty Bay 7.5' Quadrangle, King and Pierce Counties, Washington by D. B. Booth, etc (2004). PACLAND Project # 10518004 Page 11 Advance Auto Parts Preliminary Technical Information Report Section 2 - Conditions and Requirements Federal Way, Washington As required by the 2016 King County Surface Water Design Manual (KCSWDM) this project is subject to a full drainage review. Therefore, the storm drainage design for this project is required to comply with all eight (8) Core Requirements, and five (5) Special Requirements. The requirements have been met as follows: Core Requirement #1: Discharge at Natural Location All surface and storm water runoff from a project must be discharged at the natural location so as not to be diverted onto or away from downstream properties. The manner in which runoff is discharged from the project site must not create a significant adverse impact to downhill properties or drainage systems. Response: Runoff within the project site will be co![ected, conveyed, and treated within Stormfilter structures (ZPG to CSF treatment train) to provide enhanced water quality treatment All site runoff is subsequently conveyed to the stormwater main in South 336th Street. The ultimate site discharge location is to be maintained. No downstream impacts are anticipated as a result of the Proposed improvements. Core Requirement #2: Off -site Analysis All proposed projects must identify the upstream tributary area and perform a downstream analysis. Levels of analysis required depend on the problems identified or predicted. At a minimum, a Level 1 downstream analysis must be submitted with the initial permit application. Response: See Section 3 of this report for a complete off -site analysis. Core Requirement #3: Flow Control All proposed projects, including redevelopment projects, must provide onsite flow control facilities or flow control BMPs or both to mitigate the impacts of storm and surface runoff generated by new impervious surface, new pervious surface, and replaced impervious surface targeted for flow mitigation. Response: The subject site lies within the Conservation Flow Control Area (existing (NOT historic) site conditions Level 2 flow control standard). The proposed redevelopment project exceeds the threshold for new and/or replaced impervious surface, however per exception 2, fisted in Section 1.2.3-g of the KCSWDM, the project is exempt from flow control requirements as the redeveloped site will not increase the 1 QD year peak flaw by more than o.1 cfs. This provision applies to existing (NOT historic) conditions. Therefore, no flow control facilities are proposed as part of this project See Appendix B — Design Ca[ru[ations of this report for the KCRTS analysis of pre vs. post development conditions. PACLAND Project # 10518004 Page 12 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington I Core Requirement #4: Conveyance System All engineered conveyance system elements for proposed projects must be analyzed, designed, and constructed to provide a minimum level of protection against overtopping, flooding, erosion, and structural failure. Response: All new conveyance links have been designed to convey the 100 year peak flow. See Appendix B — Design Calculations of this report for analysis and basis of design for all proposed conveyance links. Core Requirement #5: Erosion and Sediment Control All proposed projects that will clear, grade, or otherwise disturb the site must provide erosion and sediment controls to prevent, to the maximum extent practicable, the transport of sediment from the project site to downstream drainage facilities, water resources, and adjacent properties. Both temporary and permanent ESC measures shall be implemented. Response: Erosion and sediment control requirements will be an integral part of the project construction documents. These measures will include methods to reduce erosion of onsite site soils and to prevent sediments from inadvertently leaving the project site. Additionally, the ESC measures will prevent sediment -laden discharge from entering the existing/proposed storm water quality or flow control facilities. Core Requirement #6: Maintenance and Operations Maintenance and operation of all drainage facilities is the responsibility of the property owner, except those facilities for which the City of Federal Way assumes maintenance and operation, and must be maintained and operated in accordance with King County or other maintenance standards as approved by the City of Federal Way. Response: An Operations and Maintenance Manual will be included in the submittal for civil permit. Core Requirement #7: Financial Guarantees and Liability All drainage facilities constructed or modified for projects must comply with the financial guarantee requirements in King County Ordinance 12020 and the liability requirements of King County Code 9.04.100. The applicant must also maintain liability insurance. Response: See Section 9 - Bond Quantities, Facility Summaries, and Declaration of Covenant. The Site Improvement Bond Quantity Worksheet and Declarations of Covenants will be submitted upon approval of the Building Permit plans. PACLAND Project # 10518004 Page 13 Advance Auto Parts Preliminary Technical Information Report p Federal Way, Washington Core Requirement #8: Water Quality All proposed projects, including redevelopment projects, must provide water quality (WQ) facilities to treat the runoff from those new and replaced pollution -generating impervious surfaces and new pollution -generating pervious surfaces targeted for treatment. Response: The proposed project will provide enhanced water quality treatment through the implementation of Stormfrlter treatment structures (ZPG to CSF treatment train) to mitigate the harmful effects to water quality created by the replaced/existing pollution generating impervious surfaces targeted for treatment within the project site. Special Requirement #J: Other Adopted Area -Specific Requirements The City of Federal Way may apply requirements for controlling drainage on an area -specific basis. Potential other adopted area -specific requirements may include: Master Drainage Plans, Basin Plans, Stormwater Compliance Plans, etc. Response: The project site does not lie within a designated critical drainage area. Special Requirement #2: Flood Hazard Area Delineation those components that are applicable and delineate them on the project's If a proposed project contains or is adjacent to a flood hazard area the project must determine site improvement plans and recorded maps. Response: The project does not lie within a Flood Hazard Area. Special Requirement #3: Flood Protection Facilities Proper analysis, design, and construction are necessary to protect against the potentially catastrophic consequences if flood protection facilities such as levees and revetments should fail. Response: The project does not require flood protection facilities. Special Requirement #4: Source Control If a proposed project requires a commercial building or commercial site development permit, then the water quality source controls applicable to the proposed project shall be applied in accordance with the king CountyStormwater Pollution Prevention Manual and King County Code 9.12. Response: Water quality source controls will be applied in accordance with the KCSWDM and King County Code 9 12. A pollution prevention plan has been included in Section 8 of this report. PACLAND Project # 10518004 Page 14 Advance Auto Parts Preliminary Technical Information Report P Federal Way, Washington Special Requirement #5: Oil Control Projects proposing to develop or redevelop a high -use site must provide oil control in addition to other water quality controls required. Response; The KCSWDm defines a high -use site as a commercial site that has an expected average daily traffic (ADT) count equal to or greater than 100 vehicles per 1,000 s f of gross building area. The project site proposes the construction of an Automobile Part Sales building (ITE Land Use Code 843) with an anticipated ADT count of 61.91 vehicles per 1,0oo sf Therefore, oil control will not be required for the subject site. PACLAND Project # 10518004 Page 15 Advance Auto Parts Preliminary Technical Information Report =SectionSite Analysis Upstream Analysis Federal Way, Washington Based on topographic survey and field reconnaissance, there is minimal tributary area to the project site. Runoff within Pacific Hwy S. and S 336th St. sheet flows to the curb and gutters adjacent to the roadway where it is collected and conveyed to multiple catch basin inlets. The hotel parking lot to the north sheet flows to pervious landscaping areas, and the area to the east of the site is a combination of wooded area and residential yards down gradient from the project site. Therefore, there is limited to no potential for storm water runoff to enter the project site. �] Downstream Analysis lThe proposed redevelopment of the subject site will result in no changes to the existing flow rate by essentially maintaining the amounts of impervious and pervious area on site. Therefore, a complete Level 1 downstream analysis has not been performed. The existing drainage patterns for the site are to be maintained. Evidence Of Existing or Predicted Problems There is no evidence of drainage problems on or near the project site. There is no record of significant flooding or drainage complaints within 1/4 mile of the project site. In addition, no drainage problems are predicted as a result of the proposed improvements. PACLAND Project # 10518004 Page 16 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington The proposed project will result in more than 2,000 square feet of new plus replaced impervious area. Typically, this would require peak runoff control such that the post -developed peak rate matches that of the historic 2-year, 10-year and 100-year peak discharge rates. However, if the proposed re -development will not increase the 100-year peak flow by greater than 0.1 cfs and the increased runoff (if any) will not significantly impact a critical area, severe flooding problem, or severe erosion problem, then the facility requirement is waived. Hydrologic Analysis The existing and proposed site conditions were evaluated using the King County Runoff Time Series (KCRTS). The detailed KCRTS outputs have been included in Appendix B — Design Calculations. The historic 1-hour duration in the Sea-Tac rainfall region (location scale factor ST-1.0) was used to model runoff in KCRTS. Existing Site Hydrology The existing site consists of a 1.82-acre parcel of developed land consisting of one building, paved parking, and landscaped areas. There is currently an existing storm drainage system in place designed to collect storm water runoff at strategically placed locations throughout the site. The storm water is then conveyed through underground pipes until discharging to a storm main beneath S 3361h St. The pre -development (existing) conditions and peak runoff rates for the project site area are shown in Tables 4 and 5 below. See Appendix B for the KCRTS outputs for the existing site condition. Table 4 — Pre -Development (Existing) Conditions Area Surface AC Roof f0.11 0.87 AC Pavement (PGIS) 0.84 AC Landscaping (Pervious) Table 5 — Pre -Development (Existing) Peak Runoff Rates Event ate (cfs)� 2-year 0.498 10-year I_ 0.879 100-year 1.78 PACLAND Project # 10518004 Page 17 Advance Auto Parts Preliminary Technical Information Report p Federal Way, Washington Developed Site Hydrology The developed site hydrology will have similar hydrology to the existing site. The new conveyance system will likely increase the amount of catch basins on site and add water quality treatment structures. The amount of impervious surface will remain the same with the only change being a subtraction of impervious paving for an addition of impervious roof area. The Post -developed condition and peak runoff rates for the entire attributed basin area (1.82 AC) are shown in tables 6 and 7 below. See Appendix B for the KCRTS outputs for the developed site condition. Table 6 — Post-Develo ment Conditions Developed Conditions Area Surface 0.16 AC Roof 0.82 AC Pavement (PGIS) 0.84 AC Landscaping (Pervious) Table 7 — Post-Devel, lo ment Peak Runoff Rates Peak Runo f f Rate Rate (cfs) OD#eveloped 0.502 0.885 1.79 Performance Standards As specified in Section 1.2.4.2, the existing onsite conveyance system does not need to be analyzed as it will not experience a change (increase) in flow characteristics (e.g., peak flows or volume of flows) as a result of the proposed project. Flow Control Analysis The post developed 100-year peak runoff rate for the overall site increased by apl3roximately 0.01 cfs from the pre -development (existing) site condition. As this project is located in the Conservation Plow Control area, it qualifies for the aforementioned exception to Core Requirement #3 by not increasing the 100-year peak runoff rate by more than 0.1 cfs, therefore any additional flow control facility requirement is waived for this project. PACLAND Project # 10518004 — Page 18 Advance Auto Parts Preliminary Technical Information Report p Federal Way, Washington Water Quality System ------------ The proposed re -development includes the demolition of the existing Columbia Bank Building (4,792 sf) and construction of a new Advance Auto Parts Building (6,970 sfl with associated parking and landscape improvements. The project lies within an Enhanced Basin Water Quality Area and the proposed improvements will create a total area of new and/or replaced pollution generating impervious surfaces (PGIS) which exceeds 5,000 sf. Therefore, this project is required to provide Enhanced Basic Water Quality treatment for all runoff from pollution generating impervious surfaces. Conveyance Per the 2016 King County Surface Water Design Manual, Section 4.2.1.2, the on -site stormwater conveyance can be calculated based on gravity flow analysis of the piping network. Peak run-off associated with and up to a 25-year storm event has been determined to be adequate. Uniform flow analysis utilizing Manning's equation, shown below, was employed with a Manning's Roughness Coefficient (n) of 0.012. Conveyance calculations are provided in Appendix B. Manning's equation - Q=1.4Y xgxR2/3xS1i2 With: n Q Flow (CFS) n = Manning's Roughness Coefficient (0.012) A = Flow Area (SF) R = Hydraulic Radius = Area /Wetted Perimeter (LF) S = Slope of the pipe (ft/ft) The developed sub basin generates a 100-year peak flow of 1.79 cfs which the existing conveyance system can more than adequately handle for both -the 25-year and 100-year storm event. All new conveyance pipes will be designed to convey up to the 100-year storm event. 100-Year Flood/Overflow Condition Review of the current FEMA FIRM map number 53033C1250F indicates that the project site lies within the Zone X, which is determined to be outside of the 100-year flood plain. The stormwater system for this project has been designed to address the storm events in accordance with design criteria described previously. In the event of a larger storm, it is unlikely that the system would fail. Based on a review of the site and immediate surroundings, if the existing storm system were to experience a major storm event, excess flows will be conv and released as they have done historically. eyed, detained, PACLAND Project # 10518004 Page 19 Advance Auto Parts Preliminary Technical Information Report Section 6- Special Reports and Studies Federal Way, Washington The following Special Reports and Studies have been submitted as part of this project: Section 7- Other Permits The following governmental approvals or permits will likely be required for this project: • City of Federal Way Process II Site Plan Review • City of Federal Way Building Permit ■ City of Federal Way Boundary Line Adjustment • Lakehaven Utility District Sewer Permit • Lakehaven Utility District Water Permit These permits will require approval by the City of Federal Way Planning Division and Lakehaven Utility District. Section 8- CSWPPP Analysis and Design All erosion and sediment control measures shall be governed by the requirements of the City of Federal Way and the Washington State Department of Ecology. A temporary erosion and sedimentation control plan will be prepared to assist the contractor in complying with these requirements. The Erosion and Sediment Control (ESC) plan will be included with the construction plans. 1. Erosion Risk Assessment The degree of erosion risk on the proposed project site is average. The following factors contribute to an average degree of erosion risk: • The site slopes relatively steeply towards S 336th St. therefore runoff could travel at increased velocities across the site. ■ The site consists of a large amount of pervious area. 2. Construction Sequence and Procedure The proposed development will include an erosion/sedimentation control plan designed to prevent sediment -laden run-off from leaving the site during construction. The erosion potential of the site is influenced by four major factors: soil characteristics, vegetative cover, topography, and climate. Erosion/sedimentation control is achieved by a combination of structural measures, cover measures, and construction practices that are tailored to fit the specific site. Prior to the start of any grading activity upon the site, all erosion control measures shall be installed in accordance with the construction documents. PACLAND Project # 10518004 Page 20 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington The best construction practice will be employed to properly clear and grade the site and to schedule construction activities. The planned construction sequence for the construction of the site is as follows: 1. Attend a pre -construction meeting with the City of Federal Way. 2. Install temporary erosion control features. 3. Demolish existing curbs. 4. Clear and grub site, if necessary. 5. Grade site. 6. Construct buildings. 7. Pave site and install landscaping. 8. Remove temporary erosion control features once site is fully stabilized. - 3. Trapping Sediment Structural control measures will be used to reduce erosion and retain sediment on the construction site. The control measures will be selected to fit specific site and seasonal conditions. The following structural items will be used to control erosion and sedimentation processes: { Catch Basin Inlet Sediment Protection • Proper Cover measures • Erosion fences/eels Weekly inspection of the erosion control measures will be required during construction. Any sediment buildup shall be removed and disposed of off -site. Vehicle tracking of mud off -site shall be avoided. A wheel wash area is to be installed if tracking of mud onto public streets becomes excessive. In the event that mud is tracked off site, it shall be swept and disposed of offsite on a daily basis. Depending on the amount of tracked mud, a vehicle road sweeper may be required. The contractor will not be allowed to leave soils open for more than 7 days between May 1 and September 30 and 2 days between October 1 and April 30, and in some cases, immediate seeding or mulching will be required, or other approved measures may be utilized. Areas next to paved areas may be armored with crushed rock sub -base in place of other stabilizing measures. 4. Wet Season TESC Operating Plan Work between October 1st and April 301h must adhere to the Wet Season Special Provisions noted in the 2016 KCSWDM. PACLAND Project # 10518004 Page 21 Advance Auto Parts Preliminary Technical Information Report p Federal Way, Washington The following items will be submitted upon application for the civil permits: • Site Improvement Bond Quantity Worksheet • Declaration of Covenant for Privately Maintained WQ Facilities. A manual detailing the operations and maintenance for all privately -maintained flow control and conveyance facilities will be submitted upon application for civil permits. This manual will also include Appendix A of the KCSWDM {Maintenance Requirements for Flow Control, Conveyance, and WQ Facilities}. PACLAND Project # 10518004 Page 22 Advance Auto Parts Preliminary Technical Information Report p Federal Way, Washington Appendix A - Exhibits PACLAND Project # 10518004 —— Page 23 Advance Auto Parts PACLAND Preliminary Technical Information Report Federal Way, Washington Exhibit 1— Existing Basin Map Project # 10518004 Page 24 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington C Exhibit 2 - Proposed Basin Map SOUTH, STFEET 9MwAM.-0P.W,» BASIN MAP ! DEVELOPED CONDITIONS EXHIBIT 2 . SCALE 1' -50' PACLAND Project # 10518004 Page 25 Advance Auto Parts PACLAND Preliminary Technical Information Report Federal Way, Washington Exhibit 3 - Grading and Drainage Plan ILS 0 qp, 5-. 0 3. -M7 21 r L -E ID 0 0 M 71 0 C 0 z > z > xq r_U > V 8 Z M, S k0 >g 0 0 a P PACIFIC HK3HWAYSOUTH SH-99 :< > 2 Inc .4 z C) 0. 2 o 16 I Ef, Project # 10518004 Page 26 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Appendix B - Design Calculations PACLAND Project # 10518004 Page 27 Advance Auto Parts Preliminary Technical Information Report _ _ __ _ _Federal Way, Washington Pre -developed Conditions (KCRTS Input): ,-Area - - - - -'.I Till Forest 0.39 acres Till Pasture] O.DO acres Till Grass D.46 acres Outwash Forest O.00 acres Outwash Pasture 0.00 acres Outwash Grass 0.00 acres Welland 0.00 acres Impervious 0.97 acres Total 1.82 acres Scale Factor: 1.00 15-Min Historic Edit Flow Paths Time Series: Compute Time Series Modify User Input To route the Unit Runoff File, Edit Paths Pre -Developed Peak Flow Rates (KCRTS Output): Mean= —0.264 StdDev= 0.158 Skew= 1.394 -----Flow Frequency Analysis------- - — Peaks — — Rank Return Prob (CFS) Period 1.78 100.00 0.990 1.45 50.00 0.980 1.17 25.00 0.960 0.879 10.00 0.900 0.830 8.00 0-875 0-699 5.00 0.800 0.498 2.00 0.500 0.408 1.30 0.231 PACLAND Project # 10518004 Page 28 Advance Auto Parts Preliminary Technical Information Report fp Federal Way, Washington Developed Conditions (KCRTS Input): Area - -- -—- ----- 2; Till Forest 0.39 acres Till Pasture 0.00 acres Till Grass 0.46 acres Outwash Forest 0.00 acres Outwash Pasture 0.00 acres Outwash Grass 0.90 acres Wetland 0.00 acres' Impervious 0.97 acres, Total - 1.82 acres Scale Factor: 1.0() 15-Min H' t ' is ortc Edit Flow Paths Time Series: Compute Time Series Modify User Input To route the Unit Runoff File, Edit Paths Developed Peak Flow Rates (KCRTS Output): Mean= -0.264 StdDev= 0.158 Skew= 1.394 -----Flow Frequency Analysis --------_ - - Peaks - - Rank Return P,rob (CFS) Period 1.79 100.00 0.990 1.45 50.00 0.980 1.18 25.00 0.960 0.885 10.00 0.900 0.836 8.00 0.875 0.704 5.00 0.800 0.502 2.00 0.500 0.412 1.30 0.231 PACLAND Project # 10518004 - Page 29 Advance Auto Parts Preliminary Technical Information Report p Federal Way, Washington Conveyance Calculations: 4 1.4 Manning's equation: Q- n xAxR2/3XSli2 With: Q = Flow (CFS) n = Manning's Roughness Coefficient (0.012) A = Flow Area (SF) R = Hydraulic Radius = Area /Wetted Perimeter (LF) S = Slope of the pipe (ft/ft) 12" Pipe @ 0.5% slope: 1.49/ Q= / n xAxR2/3XSi/2 n = 0.012 A = 0.785 (SF) R = 0.30 @ 95% full S = 0.005 QCAPAcnY = 2.78 CFS PACLAND Project # 10518004 Page 30 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Appendix C - Geotechnicai Engineering Report PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report p Federal Way, Washington RILEYGRUUP GEOTECHNICAL ENGINEERING REPORT PREPARED BY: F� THE RILEY GROUP, INC. 1111 17522 BOTHELL WAY NORTHEAST l BOTHELL, WASHINGTON 98011 _1 PREPARED FOR: CADENCE DEVELOPMENT 4580 KLAHANIE DRIVE SE, #402 ISSAQUAH, WASHINGTON 98029 RGI PROJECT No. 2015-145 PROPOSED ADVANCE AUTO PARTS 33370 PACIFIC HIGHWAY SOUTH FEDERAL WAY, WASHINGTON OCTOBER 23, 2015 Corporote 00" 17522 Bothell Way Northeast Bothell, Washington 98011 Phone 425.415,0551 • Fox 425,415,0311 W K'N'• ril eygroup. com PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington m I ■r RILEYGROUP October 23, 2015 Mr. Jeff Parker Cadence Development 4580 Klahanie Drive SE, 4402 Issaquah, Washington 98029 Subject: Geotechnical Engineering Report Proposed Advance Auto Parts 33370 Pacific Highway South Federal Way, Washington RGI Project No. 2015-145 Dear Mr. Parker: As requested, The Riley Group, Inc. (RGI) has performed a Geotechnical Engineering Report (GER) for the Proposed Advance Au to Parts located at 33370 Pacific Highway South, Federal Way, Washington. Our services were completed in accordance with our proposal PRP2015- 235 dated September 10, 2015 and authorized by Gregory B. Ham, COO with Cadence Development on September 23, 2015. The information in this GER is based on our understanding of the proposed construction, and the soil and groundwater conditions encountered in the borings completed by RGI at the site on October 14, 2015. RGI recommends that you submit the project plans and specifications to RGI for a general review so that we may confirm that the recommendations In this GER are interpreted and implemented properly in the construction documents. RGI also recommends that a representative of our firm be present on site during portions of the project construction to confirm that the soil and groundwater conditions are consistent with those that form the basis for the engineering recommendations in this GER. If you have any questions or require additional information, please contact us. Respectfully submitted, THE RILEY GROUP, INC. ERIC L. WOODS Eric L. Woods, LG Project Geologist Ta-ma, Washington Phone 253,565.0552 Corporate office 1%522 Bothell Way Northenst Bnthell, Washington 9g011 Phone 425.4I5.0551 4 Fox 425.415.0321 www.riley-grolip.com Senior Project Engineer Kennewirk, Washington Phone 509.586.4840 PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington I J 1 J PACLAND Geotechnical Engineering Report October23, 2015 Advance Auto Parts, Federal Way, Washington RGl Project No. 2015-138 TABLE OF CONTENTS 1.0 INTRODUCTION ...............................................................................................................................1 2.0 PROJECT DESCRIPTION...............................................................................................................1 3.0 FIELD EXPLORATION AND LABORATORY TESTING.......................................................... t 3.1 FIELD EXPLORATION...................................................................................................................................1 3.2 LABORATORYTESTING.......... .............. ................. ........... ........ .............. ....................... ..................*."*-"",,2 4.0 SITE CONDITIONS...........................................................................................................................2 4.1 SURFACE..................................................................................................................................................2 4.2 GEOLOGY.................................................................................................................................................2 4.3 SOILS.......................................................................................................................................................2 4.4 GROUNDWATER........................................................................................................................................3 4.5 SEISMIC CONSIDERA110NS...........................................................................................................................3 4.6 GEOLOGIC HAZARD AREAS..........................................................................................................................4 5.0 DISCUSSION AND RECOMMENDATIONS ........... .. _. .» 4 S.1 GEOTECHNICAL CONSIDERATIONS .................................................................................................................4 5.2 EARTHwm.............................................................................................................................................4 5.2.1 Erosion and Sediment Control.......................................................................:.............................4 5.2.2 Stripping........................................................... .............................................. :....... ...................... S 5.2.3 Excavations...................................................................................................................................5 5.2.4 Site Preparation...........................................................................................................................6 5.2.5 Structural Fill... ............ . ................................. . . . . ....................................................................... 6 5.2.6 Cut and Fill Slopes........................................................................................................................8 5.2.7 Wet Weather Construction Considerations.................................................................................8 5.3 FOUNDATIONS..........................................................................................................................................9 5.4 RETAINING WALLS................................................................................................................................... 10 5.5 SLAB -ON -GRADE CONSTRUCTION ............................ ............... ..................... .... ................... I.......................10 5.6 DRAINAGE.............................................................................................................................................. 11 5.6.1 Surface.......................................................................................................................................11 5.6.2 Subsurface..................................................................................................................................11 5.6.3 Infiltration ....... ........ ........... ........................ .............. ».»................... ...........« ............................11 5.7 UTILITIES................................................................................................................................................11 5.8 PAWIVENTS:................... ............ ....................... ....................................................... : ............................. 11 6.0 ADDITIONAL SERVICES ........ ................................... ............................................ .... ... ............ 12 7.0 LIMITATIONS .... .............................. ................................................ ............ ...................... .......... 12 LIST OF FIGURES AND APPENDICES FigureI.........................................................................................................Site Vicinity Map Figure 2................................................................................... Geotechnical Exploration Plan Figure 3..................................................................... Typical Retaining Wall Drainage Detail Figure4....................................................................................... Typical Footing Drain Detail Appendix A ............................................................ Field Exploration and Laboratory Testing ■ow I ILM RILEYGROUP Project # 10518004 Page 31 I .J Advance Auto Parts Preliminary Technical Information Report Geotechnical Engineering Report Advance Auto Parts, Federal Way, Washington Executive Summa Federal Way, Washington Oct0ber23,1015 RG/Project No, 2015-138 This Executive Summary should be used in conjunction with the entire Geotechnical Engineering Report (GER) for design and/or construction purposes. It should be recognized that specific details were not included or fully developed in this section, and the GER must be read in its entirety for a comprehensive understanding of the items contained herein. Section 7.0 should be read for an understanding of limitations. RGI's geotechnical scope of work included the advancement of 12 borings to approximate depths of 10.5 to 16.5 feet below existing site grades. Based on the information obtained from our subsurface exploration, the site is suitable for development of the proposed project. The following geotechnical considerations were identified: Soil Conditions: The soils encountered during field exploration include medium dense fill comprised of silty sand with some gravel and medium dense to very dense native silty sand with some gravel over very dense glacial till. Groundwater: A groundwater table was not encountered during our subsurface exploration. Foundations: Foundations for the proposed building may be supported on conventional spread footings bearing on medium dense native soils or structural fill. Slab -on -grade: Slab -on -grade floors and slabs for the proposed building can be supported on medium dense native soil or structural fill. Pavements: The following pavement sections are recommended: For heavy truck traffic areas: 3 inches of Hot Mix Asphalt (HMA) over 6 inches of crushed rock base (CRB) For general parking areas: 2 inches of HMA over 4 inches of CRB ■1= 12 bi In RILEYGROUR PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Groecch+li[or Engineering Report 1 Adronre Auto Parrs, Freeror Way, Washington October 23, 2015 RGI Project No. 2015-145 1.0 Introduction This Geotechnical Engineering Report (GER) presents the results of the geotechnical engineering services provided for the Proposed Advance Auto Parts in Federal Way, Washington. The purpose of this evaluation is to assess subsurface conditions and provide geotechnical recommendations for the construction of a new Advance Auto Parts retail store. Our scope of services included field explorations, laboratory testing, engineering analyses, and preparation of this GER. The recommendations in the following sections of this GER are based upon our current understanding of the proposed site development as outlined below. If actual features vary or changes are made, RGI should review them in order to modify our recommendations as required. In addition, RGI requests to review the site grading plan, final design drawings and specifications when available to verify that our project understanding is correct and that our recommendations have been properly interpreted and incorporated into the project design and construction. 2.0 Project description The project site is located at 33370 Pacific Highway South in Federal Way, Washington. The approximate location of the site is shown on Figure 1. The subject site consists of two parcels of land totaling approximately 1.82 acres. The site is occupied by an existing one-story bank building with paved parking. RGI understands the existing structure is to be demolished to make way for a new 6,412 square foot Advance Auto Parts retail store, a new 4,030 square foot retail store, and associated parking and drive areas. The proposed buildings will be one-story masonry buildings with slab -on -grade floors. A water q u a lity/stormwa te r detention area is proposed far the southern portion of the site. At the time of preparing this GER, building plans were not available for our review. Based an our experience with similar construction, RGI anticipates that the proposed building will be supported on perimeter walls with bearing loads Of four to six kips per linear foot, and a series of columns with a maximum load up to 200 kips. Slab -on -grade floor loading of 250 pounds per square foot (psf) are expected. 3.0 Field Exploration and Laboratory Testing 3.1 FIELD EXPLORATION On October 14, 2015, RGI observed the drilling of 12 borings. The approximate exploration locations are shown on Figure 2. Field logs of each exploration were prepared by the geologist that continuously observed the drilling. These logs included visual classifications of the materials encountered during ■ice ■ !IM RILEYGR©UR PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Geotechniccl Engineering Report 2 Advance Auto Parts, Federal Way, Washington October 23, 2015 RGl Proiecl No 2013-145 drilling as well as our interpretation of the subsurface conditions between samples, The borings logs included in Appendix A represent an interpretation of the field logs and include modifications based on laboratory observation and analysis of the samples. 3.2 LABORATORY TESTING During the field exploration, a representative portion of each recovered sample was sealed in containers and transported to our laboratory for further visual and laboratory examination. Selected sampfes retrieved from the borings were tested for moisture content and grain size analysis to aid in soil classification and provide input for the recommendations provided in this GER. The results and descriptions of the laboratory tests are enclosed in Appendix A. 4.0 Site Conditions 4.1 SURFACE The subject site is a rectangular -shaped lot containing two parcels of land totaling approximately 1.82 acres in size. The site is bound to the north by a motel, to the east by residential property, to the south by South 336th Street, and to the west by Pacific Highway South. The existing site is occupied by a single story bank building and paved parking, with trees and decorative shrubs located in planter areas throughout the site. A forested strip of land is located along the eastern edge of the site. The site slopes generally south with approximately 20 feet of elevation change across the site. 4.2 GEOLOGY RGI reviewed the Geologic Map Of The Poverty Bay 7.5' Quadrangle, King And Pierce Counties, Washington by D. B. Booth, etc (2004). The review indicates that the soil in the project vicinity is mapped as Recessional outwash deposits (map unit Qvr), which consists of moderately sorted deposits of sand and gravel deposited by meltwater streams issuing from the receding Vashon glacier. The soil to the north, south and east of the project vicinity is mapped as Vashon till (Qt), which is light to dark gray, nonsorted, nonstratified mixture of clay, silt, sand, and gravel. These descriptions are generally similar to the findings in the borings with outwash deposits nearthe surface and till in the lower portions. 4.3 SOILS The soils encountered during field exploration include medium dense fill comprised of silty sand with some gravel and medium dense to very dense native silty sand with some gravel over very dense silty sand with gravel (glacial till). More detailed descriptions of the subsurface conditions encountered are presented in the borings included in Appendix A. Sieve analysis was performed on three selected soil samples. Grain size distribution curves are included in Appendix A. PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Geafechakof Eagineering Report 3 Ad,un-Auto pork, Fednra! Way, Washington October 23, 2015 RG! Project No. 2015-145 4.4 GROUNDWATER A groundwater table was not encountered during our subsurface exploration. Shallow groundwater seepage may be encountered at the interface of the outwash and glacial till soils in the wetter winter and spring months. It should be recognized that fluctuations of the groundwater table will occur due to seasonal variations in the amount of rainfall, runoff, and other factors not evident at the time the explorations were performed. In addition, perched water can develop within seams and layers contained in fill soils or higher permeability soils overlying less permeable soils following periods of heavy or prolonged precipitation. Therefore, groundwater levels during construction or at other times in the future may be higher or lower than the levels indicated on the logs. Groundwater level fluctuations should be considered when developing the design and construction plans for the project. 4.5 SEISMIC CONSIDERATIONS Based on the 2012 International Building Code (IBC), RGI recommends the follow seismic parameters for design. Table 12012 IBC Parameter Value Site Soil Class' C2 Site Latitude Site Longitude - Short Period Spectral Response Acceleration, S (g) 1-Second Period Spectral Response Acceleration, 51 (g) Adjusted Short Period Spectral Response Acceleration, SMs (g) Adjusted 1-Second Period Spectral Response Acceleration, SMt (g) 47.301248' N 122.3126810 W 1.285 0.494 1.285 0.645 ---- the dace ro accordance with chapter 20 of ASCE 7. The Site Class Is based on tha average characlmsFrcx of the upper lap lees nl the subsurface profile. 2. Nate: The 2D12 ISC aWAsa 7 require a site soil pref0e determirwtida &4ending to a depth of 100 feet for sosmicsRa CIMMicatfon, The CURen[ 5[apC of our SCryj(CS dacs na! duck ' the "U'red'Do foot sat ProGfe deterrnlnatian, Sadrfgs extended W a madmum depth of 16.5 feel* and thisseis<nic sFle cfass definition rermiders that sim ifar $al centinu[y below the mamirnum depth of the subsurface eCpbG[len. Additional espfaratim 10 deeper depths would be reQuired to confirm :he COW;t[Ms below the Current depth of explorallon. Liquefaction is a phenomenon where there is a reduction or complete foss of soil strength due to an increase in water pressure induced by vibrations from a seismic event. Liquefaction mainly affects geologically recent deposits of fine-grained sands that are below the groundwater table. Soils of this nature derive their strength from intergranular friction. The generated water pressure or pore pressure essentially separates the soil grains and eliminates this intergranular friction, thus reducing or eliminating the soil's strength. i LM RILEYGROUP PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report fp Federal Way, Washington C�rofechnrcot ErtOineNrirg Report AdvvrrceAuro Ports , Flderol W. Woshingtort 4 October 23, 2015 RGI Project NO. 2015-145 RGI reviewed the results of the field and laboratory testing and assessed the potential for liquefaction of the site's soil during an earthquake. Since the site is underlain by glacial till, RGI considers that the possibility of liquefaction during an earthquake is minimal. 4.6 GEOLOGIC HAZARD AREAS Regulated geologically hazardous areas include erosion, landslide, earthquake, or other geological hazards. Based on the definitions in the Federal Way Municipal Code, the does not contain geologically hazardous areas. 5.0 Discussion and Recommendations 5.1 GEOTECHNICAL CONSIDERATIONS Based on our study, the site is suitable for the proposed construction from a geotechnical standpoint. Foundations for the proposed building can be supported on conventional spread footings bearing on medium dense native soil or structural fill. Slab -on -grade and pavements can be similarly supported. Detailed recommendations regarding the above issues and other geotechnical design considerations are provided in the following sections. These recommendations should be incorporated into the final design drawings and construction specifications. 5.2 EARTHWORK Based on the existing conditions and the proposed construction, we expect the earthwork will include excavating the new foundations, installing underground utilities and preparing slab and pavement subgrades. 5.2.1 EROSION AND SEDIMENT CONTROL Potential sources or causes of erosion and sedimentation depend on construction methods, slope length and gradient, amount of soil exposed and/or disturbed, soil type, construction sequencing and weather. The impacts on erosion -prone areas can be reduced by implementing an erosion and sedimentation control plan. The plan should be designed in accordance with applicable city and/or county standards. RGI recommends the following erosion control Best Management Practices (BMPs): i- Scheduling site preparation and grading for the drier summer and early fall months and undertaking activities that expose soil during periods of little or no rainfall Retaining existing vegetation whenever feasible 5' Establishing a quarry spall construction entrance Installing siltation control fencing or anchored straw or coir wattles on the downhill side of work areas r Covering soil stockpiles with anchored plastic sheeting PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report P Federal Way, Washington Geoiechnrco! Enprircering Repw! R :ce A4ta Pant, Frdrrot VJtry, W.shi,,gt.n 5 October 23, 2015 RGI Project No. 2015-145 Revegetating or mulching exposed soils with a minimum 3-inch thickness of straw if surfaces will be left undisturbed for more than one day during wet weather or one week in dry weather �= Directing runoff away from exposed soils and slopes Minimizing the length and steepness of slopes with exposed soils and cover excavation surfaces with anchored plastic sheeting (Graded and disturbed slopes should be tracked in plate with the equipment running perpendicular to the slope contours s❑ that the track marks provide a texture to help resist erosion and channeling. Some sloughing and raveling of slopes with exposed or disturbed soil should be expected.) y Decreasing runoff velocities with check dams, straw bales or coir wattles Confining sediment to the project site Inspecting and maintaining erosion and sediment control measures frequently (The contractor should be aware that inspection and maintenance of erosion control BMPs is critical toward their satisfactory performance. Repair and/or replacement of dysfunctional erosion control elements should be anticipated.) Permanent erosion protection should be provided by reestablishing vegetation using hydroseeding and/or landscape planting. Until the permanent erosion protection is established, site monitoring should be performed by qualified personnel to evaluate the effectiveness of the erosion control measures. Provisions for modifications to the erosion control system based on monitoring observations should be included in the erosion and sedimentation control plan. 5.2.2 STRIPPING Stripping efforts should include removal of pavements, vegetation, organic materials, and boring locations encountered 2 to 4 inches of asphalt condeleterious debris from areas slated for building, pavement, and utility construction. The rock base. crete and 4 to 6 inches of crushed 5.2.3 ExcAVATIONS All temporary cut slopes associated with the site and utility excavations should be adequately inclined to prevent sloughing and collapse. The site soils consist of medium dense to very dense silty sand soils. Accordingly, for excavations more than 4 feet but less than 20 feet in depth, the temporary side slopes should be laid back with a minimum slope inclination of 1H:1v (Horizontal -Vertical) in the medium dense native soils and 3/4H.*IV in the very dense soils. If there is insufficient room to complete the excavations in this manner, or excavations greater than 20 feet in depth are planned, using temporary shoring to support the excavations should be considered. For open cuts at the site, RGI recommends: now I ►U RILEYGROUP PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report GeolrchniCof Engineering R�pa,i 6 Advance Aut&Aun , Federal woy, Washington Federal Way, Washington October 23, 2015 RGI Project No- 2015-145 No traffic, construction equipment, stockpiles or building supplies are allowed at the top of cut slopes within a distance of at feast five feet from the top of the cut Y Exposed soil along the slope is protected from surface erosion using waterproof tarps and/or plastic sheeting �- Construction activities are scheduled so that the length of time the temporary cut is left open is minimized Surface water is diverted away from the excavation The general condition of slopes should be observed periodically by a geotechnical engineer to confirm adequate stability and erosion control measures In all cases, however, appropriate inclinations will depend on the actual soil and groundwater conditions encountered during earthwork. Ultimately, the site contractor must be responsible for maintaining safe excavation slopes that comply with applicable OSHA or WISHA guidelines. 5.2.4 SITE PREPARATION After stripping, grubbing, and prior to placement of structural fill, RGI recommends proofrolling building and pavement subgrades and areas to receive structural fill. These areas should moisture condition and compacted to a firm and unyielding condition in order to achieve a minimum compaction level of 45 percent of the modified proctor maximum dry density as determined by the American Society of Testing and Materials D1557-09 Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Modified Effort (ASTM D1557), Proofrolling and adequate subgrade compaction can only be achieved when the soils are within approximately± 2 percent moisture content of the optimum moisture content. Soils which appear firm after stripping and grubbing maybe proofrolled with a heavy compactor, loaded double -axle dump truck, or other heavy equipment underthe observation of an RGI representative. Subgrade soils that become disturbed due to elevated moisture conditions should be overexcavated to reveal firm, non -yielding, non -organic soils and backfilled with compacted structural fill. In order to maximize utilization of site soils as structural fill, RGI recommends that the earthwork portion of this project be completed during extended periods of warm and dry weather if possible. If earthwork is completed during the wet season (typically November through May) it will be necessaryto take extra precautionary measures to protect subgrade soils. Wet season earthwork will require additional mitigative measures beyond that which would be expected during the drier summer and fall months. 5.2.5 STRUCTURAL Flu Once stripping and other preparing operations are complete, cuts and fills can be made to establish desired building grades. Prior to placing fill, RGI recommends proof -rolling as described above. RGI recommends fill below the foundation and floor slab, behind ■ice RiLEYGROUP PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Geotechnicot Engineering Report 7 October 23, 2015 AdvanceAuto Ports, federal Way, Washington RGl Project No. 1025-145 retaining walls, and below pavement and hardscape surfaces be placed in accordance with the following recommendations for structural fill. The structural fill should be placed after completion of site preparation procedures as described above. The suitability of excavated site soils and import soils for compacted structural fill use will depend on the gradation and moisture content of the soil when it is placed. As the amount of fines (that portion passing the U.S. No. 200 sieve) increases, soil becomes increasingly sensitive to small changes in moisture content and adequate compaction becomes more ' difficult or impossible to achieve. Soils containing more than about 5 percent fines cannot be consistently compacted to a dense, non -yielding condition when the moisture content is more than 2 percent above or below optimum. optimum moisture content is that —� moisture that results in the greatest compacted dry density with a specified compactive effort. Non -organic site soils are only considered suitable for structural fill provided that their moisture content is within abouttwo percent of the optimum moisture level as determined by ASTM D1557. Excavated site soils may not be suitable for re -use as structural fill depending on the moisture content and weather conditions at the time of construction. If soils are stockpiled forfuture reuse and wet weather is anticipated, the stockpile should be protected with plastic sheeting that is securely anchored. Even during dry weather, moisture conditioning (such as, windrowing and drying) of site soils to be reused as structural fill may be required. Even duringthe summer, delays in grading can occur due to excessively high moisture conditions of the soils or due to precipitation. If wet weather occurs, the upper wetted portion of the site soils may need to be scarified and allowed to dry prior to further earthwork, or may need to be wasted from the site. I I PACLAN D The native soils encountered should be suitable for use as structural fill in dry weather provided they can be moisture conditioned. If on -site soils are or become unusable, it may become necessary to import clean, granular soils to complete site work that meet the grading requirements listed in Table 2 to be used as structural fill. Table 2 Structural Fill Gradation U.S. Sieve Size , Percent Passing 4 inches 100 No. 4 sieve 75 percent No. 200 sieve 5 percent " 't,--d on minus 3/4 inch frawon. Prior to use, an RGI representative should observe and test all materials imported to the site for use as structural fill. Structural fill materials should be placed in uniform loose layers A I ►IM RILEYGROUP Project # 10518004 Page 31 J Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Geotechnical Engineering Report 8 Advance Auto Parts, Federal Way, Washington October 23, 20I5 RGI Project No. 2025-145 not exceeding 12 inches and compacted as specified in Table 2. The soil's maximum density and optimum moisture should be determined by ASTM 01557. Table 3 Structural Fill Compaction ASTM DiSS7 Minimum Location Material Type Compaction Moisture Content Percentage Range Foundations On -site granular or approved imported fill soils: 95 I +2 I -2 Retaining Wall Backfill On -site granular or approved imported fill soils: 92 +2 -2 Slab -on -grade On -site granular or approved Imported fill soils: 95 +2 -2 General Fill (non- on -site soils or approved structural areas) imported fill soils: 90 +3 -2 Pavement—Subgrade on -site granular or approved and Base Course imported fill soils: 95 +2 -2 Placement and compaction of structural fill should be observed by RGI. A representative number of in -place density tests should be performed as the fill is being placed to confirm that the recommended level of compaction is achieved. 5.2.6 CUT AND FILL SLOPES All permanent cut and fill slopes (except interior slopes of detention pond) should be graded with a finished inclination no greater than 2H:1V. The interior slopes of the detention pond must be graded with a slope gradient no steeper than 3H:1V. Upon completion of construction, the slope face should be trackwalked, compacted and vegetated, or provided with other physical means to guard against erosion. Final grades at the top of the slopes must promote surface drainage away from the slope crest. Water must not be allowed to flow in an uncontrolled fashion over the slope face. If it is necessary to direct surface runoff towards the slope, it should be controlled at the top Of the slope, piped in a closed conduit installed on the slope face, and taken to an appropriate point of discharge beyond the toe of the slope. 5.2.7 WET WEATHER CONSTRUCTION CONSIDERATIONS RGI recommends that preparation for site grading and construction include procedures intended to drain ponded water, control surface water runoff, and to collect shallow subsurface seepage zones in excavations where encountered. It will not be possible to successfully compact the subgrade or utilize on -site soils as structural fill if accumulated water is not drained prior to grading or if drainage is not controlled during construction. Attempting to grade the site without adequate drainage control measures will reduce the ■1= NEW RILEYGROOP PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington J J PACLAN D Geotechnicol Engineering Report 9 October 23, 2015 AdvanceAuto Ports, Federal Way, Washington RGI Project No. 2015-145 amount of on -site soil effectively available for use, increase the amount of select import fill materials required, and ultimately increase the cost of the earthwork phases of the project. Free water should not be allowed to pond on the subgrade soils. RGI anticipates that the use of berms and shallow drainage ditches, with sumps and pumps in utility trenches, will be required for surface water control during wet weather and/or wet site conditions. 5.3 FOUNDATIONS Following site preparation and grading, the proposed building foundation can be supported on conventional spread footings bearing on medium dense to dense native soil or structural fill. Loose, organic, or other unsuitable soils may be encountered in the proposed building footprint. If unsuitable soils are encountered, they should be overexcavated and backfilled with structural fill. Perimeter foundations exposed to weather should be at a minimum depth of 18 inches below final exterior grades. Interior foundations can be constructed at any convenient depth below the floor slab. Finished grade is defined as the lowest adjacent grade within 5 feet of the foundation for perimeter (or exterior) footings and finished floor level for interior footings. Table 4 Foundation Design Design Parameter I Value Allowable Bearing Capacity' 2,500 psfl Friction Coefficient 0.30 Passive pressure (equivalent fluid pressure)) 250 pcf2 Columns: 24 inches Minimum foundation dimensions Walls: 16 inches l.pst= pounds per square foot 2. pcf = pounds per cubic foot The allowable foundation bearing pressures apply to dead loads plus design live load conditions. For short-term loads, such as wind and seismic, a 1/3 increase in this allowable capacity may be used. At perimeter locations, RGI recommends not including the upper 12 inches of soil in the computation of passive pressures because they can be affected by weather or disturbed by future grading activity. The passive pressure value assumes the foundation will be constructed neat against competent soil or backfilled with structural fill as described in Section 5.2.5. The recommended base friction and passive resistance value includes a safety factor of about 1.5. elm ® Elm RILFY(:[,[ .;F Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Geotecbnical Engineering Report 10 October 23, 2015 Advance Auto Ports, Federal Way, Washington RGI Project No 2015-145 With spread footing foundations designed in accordance with the recommendations in this section, maximum static total and differential post -construction settlements of 1 inch and 1/2 inch, respectively, should be expected. 5.4 RETAINING WALLS If retaining walls are needed in the building or detention area, RGI recommends cast -in - place concrete walls be used. If a detention vault is necessary, the foundations are expected to be founded on the very dense native soils and the increased bearing capacity provided below can be used. The magnitude of earth pressure development on retaining k walls will partly depend on the quality of the wall backfill. RGI recommends placing and compacting wall backfill as structural fill. Wall drainage will be needed behind the wall face. A typical retaining wall drainage detail is shown in Figure 3. With wall backfill placed and compacted as recommended, and drainage properly installed, RGI recommends using the values in the following table for design. Table 5 Retaining Wall Design Design Parameter Value Allowable Bearing Capacity— native or structural fill I 2,500 psf Very dense native soil 4,000 psf r Active Earth Pressure (unrestrained walls) 35 pcf At -rest Earth Pressure (restrained walls) ` 50 pcf +1 For seismic design, an additional uniform load of 7 times the wall height (H) for 1 unrestrained walls and 14H in psf for restrained walls should be applied to the wall surface. Friction at the base of foundations and passive earth pressure will provide resistance to these lateral loads. Values for these parameters are provided in Section 5.3. 5.5 SLAB -ON -GRADE CONSTRUCTION Once site preparation has been completed as described in Section 5.2, suitable support for `l slab -on -grade construction should be provided. RGI recommends that the concrete slab be 4 placed on top of medium dense native soil or structural fill. Immediately below the floor slab, RGI recommends placing a four -inch thick capillary break layer of clean, free -draining sand or gravel that has less than five percent passing the U.S. No. 200 sieve. This material will reduce the potential for upward capillary movement of water through the underlying sail and subsequent wetting of the floor slab. Where moisture by vapor transmission is undesirable, an 8- to 10-millimeter thick plastic membrane should be placed on a 4-inch thick layer of clean gravel. For the anticipated floor slab loading, we estimate post -construction floor settlements of 1/2 to 3/4-inch. For �ii• RILEYGROUR J PAC LA N D Project # 10518004 Page 31 J Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Geotechnical Engineering Report 11 Advance Auto Ports, Federal Way, Woshington Octaber 23, 2015 RGI Project No. 2015-145 thickness design of the slab subjected to point loading from storage racks, RGI recommends using a subgrade modulus (Ks) of 150 pounds per square inch per inch of deflection. 5.6 DRAINAGE 5.6.1 SURFACE Final exterior grades should promote free and positive drainage away from the building area. Water must not be allowed to pond or collect adjacent to foundations or within the immediate building area. For non -pavement locations, RGI recommends providing a minimum drainage gradient of 3 percent for a minimum distance of 10 feet from the building perimeter. In paved locations, a minimum gradient of 1 percent should be provided unless provisions are included for collection and disposal of surface water adjacent to the structure. 5.6.2 SUBSURFACE RGI recommends installing perimeter foundation drains. A typical footing drain detail is shown on Figure 4, The foundation drains and roof downspouts should be tightlined separately to an approved discharge facility. Subsurface drains must be laid with a gradient sufficient to promote positive flow to a controlled point of approved discharge, 5.6.3 INFILTRATION The site is underlain by very dense glacial till in the area of the proposed detention facility and infiltration is not feasible in the soils encountered. 5.7 UTILITIES Utility pipes should be bedded and backfilled in accordance with American Public Works Association (APWA) specifications. For site utilities located within the right-of-ways, bedding and backfill should be completed in accordance with City of Federal Way specifications. At a minimum, trench backfill should be placed and compacted as structural fill, as described in 5ection 5.2.5. Where utilities occur below unimproved areas, the degree Of compaction can be reduced to a minimum of 90 percent of the soil's maximum density as determined by the referenced ASTM D1557. The native soils should be suitable for use as trench backfill in dry weather provided they can be moisture conditioned. Imported structural fill meeting the gradation provided in Table 2 maybe necessary for trench backfill in wet weather conditions. 5.8 PAVEMENTS Pavement subgrades should be prepared as described in Section 5.2 and as discussed below. Regardless of the relative compaction achieved, the subgrade must be firm and relatively unyielding before paving. The subgrade should be proofroiled with heavy construction equipment to verify this condition, 1� RILEYGRGl1P PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Geotechnicol Engineering Report 12 October 23, 2015 AdvanceAuto Parts, Federal Way, Washington RGI Project No. 2015-145 With the pavement subgrade prepared as described above, RGI recommends the following pavement sections for parking and drive areas paved with flexible asphalt concrete surfacing. For heavy truck traffic areas: 3 inches of Hot Mix Asphalt (HMA) over 6 inches of crushed rock base (CRB) For general parking areas: 2 inches of HMA over 4 inches of CRB The asphalt paving materials used should conform to the Washington State Department of Transportation (WSDOT) specifications for HMA and CRB surfacing. Long-term pavement performance will depend on surface drainage. A poorly -drained pavement section will be subject to premature failure as a result of surface water infiltrating into the subgrade soils and reducing their supporting capability. For optimum pavement performance, surface drainage gradients of no less than 2 percent are recommended. Also, some degree of longitudinal and transverse cracking of the pavement surface should be expected over time. Regular maintenance should be planned to seal cracks when they occur. 6.0 Additional Services RGI is available to provide further geotechnical consultation throughout the design phase of the project. RGI should review the final design and specifications in order to verify that earthwork and foundation recommendations have been properly interpreted and incorporated into project design and construction. RGI is also available to provide geotechnical engineering and construction monitoring services during construction. The integrity of the earthwork and construction depends on proper site preparation and procedures. In addition, engineering decisions may arise in the field in the event that variations in subsurface conditions become apparent. Construction monitoring services are not part of this scope of work. If these services are desired, please let us know and we will prepare a cost proposal. 7.0 Limitations This GER is the property of RGI, Cadence Development, and its designated agents. Within the limits of the scope and budget, this GER was prepared in accordance with generally accepted geotechnical engineering practices in the area at the time this GER was issued. This GER is intended for specific application to the Proposed Advance Auto Parts project in Federal Way, Washington, and for the exclusive use of Cadence Development and its authorized representatives. No other warranty, expressed or implied, is made. Site safety, excavation support, and dewatering requirements are the responsibility of others. The scope of services for this project does not include either specifically or by implication any environmental or biological (for example, mold, fungi, bacteria) assessment of the site men U L RILEYGROUP Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Z*rofeY��niral fngine�ri.;y Rrporr 13 Advencr Auty Pods, frdrrul Way. Washington Oooher 23, 2015 M Pwled No. 2015-145 or identification or prevention of pollutants, hazardous materials or conditions. If the owner is concerned about the potential for such contamination or pollution, we can provide a proposal for these services. The analyses and recommendations presented in this GER are based upon data obtained from the test exploration performed on site. Variations in soil conditions can occur, the nature and extent of which may not become evident until construction. If variations appear evident, RGI should be requested to reevaluate the recommendations in this GER prior to proceeding with construction. It is the client's responsibility to see that all parties to the project, including the designers, contractors, subcontractors, are made aware of this GER in its entirety. The use of ~ information contained in this GER for bidding purposes should be done at the contractor's option and risk. now ■ Li RILEYGROUP PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington USGS, 2014, Poverty Bay, Washington Approximate Scale: 1"=1000' ■ 7.5-Minute Quadrangle /'� 0 500 1000 2D0R N • , - Corporate 17522BothelllWay Northea ® Bothell, Washington 98011 .0 Phone:425.415.0551 RILEYGROUP Fax: 425.415.0311 PACLAN D Advance Auto Parts RGI Project Number Site Vicinity Map 2015-145 Address: 33370 Pacific Highway South, Federal Way, Project # 10518004 Date Drawn: 98003 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington = Borings drilled by RGI on 1e/14/15 PACLAND Approximate Scale: V-60' A a 30 60 no N 95� e Advance Auto Parts FlgurE 2 1ay Nwihe=1 RGI Project Number Date Drawn: .-Washington Geotechnical Exploration Plan 1O12015 t�� y�+� a 5.05512O15.145MLCl GIIOUP 311 Address: 33370 Pacific H]ghway 5ou[h, Federal Way. Washington 93003 Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington 12" Minimum Wide J Free -Draining Gravel 12" min. J Filter Fabric Material Slope to Drain 4 Excavated Slope (See Report for Appropriate Incliniations) Compacted Structural Backfill (Native or Import) "'V - 12" Over the Pipe X 3" Below the Pipe 4" Diameter PVC Perforated Pipe Corporate Office Advance Auto Parts Figure 3 17522 Bothell Way Northeast RGI Project Number Date Drawn: .0 Bothell, Washington 98011 2015-145 Retaining Wall Drainage Detail 10/201S 6`'ry ryn �y Phone:425.415.0551 RfL GROUP Fax: 425.415.0311 Address: 33370 Pacific Highway South, Federal Way, Washington 98003 PACLAN D Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Building Slab 1 1 i Compacted - tructural'• �\ \ Sack Filter Fabric lo f +' �' 4" Perforated Pipe 3/4" Washed Rock or Pea Gravel Not to Scale Corporate Office Advance Auto Parts Figure 4 17522 Bothell Way Northeast RG�2015-14�5 Date Drawn: .-Bothell, Washington 98011 Typical Footing Drain Detail 10/2015 Phone: 425.415.0551 RIOGROUP Pax:425.415.0311 Address: 33370 Pacific Highway South, Federal Way, Washington 98003 PACLAN D Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report p Federal Way, Washington Georrchacet frtganeeriry Repm! Advonre ADO Parts, Federal Wary, Washington Odober 23,1015 RGt Project No. 2025-I45 APPENDIX A FIELD EXPLORATION AND LABORATORY TESTING On Uctober 14, 2015, RGI performed field explorations using a trailer -mounted drill rig. We explored subsurface soil conditions at the site by observing the drilling of 12 borings to a maximum depth of 16.5 feet below existing grade. The boring locations are shown on Figure 2. The boring locations were approximately determined by measurements from existing property lines and paved roads. A geologist from our office conducted the field exploration and classified the soil conditions encountered, maintained a log of each test exploration, obtained representative soil samples, and observed pertinent site features. All soil samples were visually classified in accordance with the Unified Soil Classification System (USCS). Representative soil samples obtained from the explorations were placed in closed containers and taken to our laboratory for further examination and testing. As a part of the laboratory testing program, the sail samples were classified in our in house laboratory based on visual observation, texture, plasticity, and the limited laboratory testing described below. Moisture Content Determinations Moisture content determinations were performed in accordance with ASTM D2216-10 Standard Test Methods for Laboratory Determination of Water (Moisture) Content of Soil and Rock by Mass (ASTM 02216) on representative samples obtained from the exploration In order to aid in identification and correlation of soil types. The moisture content of typical sample was measured and is reported on the boring logs. Grain Size Analysis A grain size analysis indicates the range in diameter of soil particles included in a particular sample. Grain size analyses was determined using D6913-04(2009) Standard Test Methods for Particle -Size Distribution (Gradation) of Soils Using Sieve Analysis (ASTM D6913) on three of the samples. son B ®V RILEYGROUP PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Project Name; Federal Way Advance Auto Parts Project Number: 2015-145 FIRI Boring No.: B-1 Client: Cadence Development, LLC E, Rr Sheet 1 of 1 W1gS}Cr1ir_-f:IOMV2015 Lo-V_,fa}: ELw airtawcnix4lans: Asptualt GHri-fvlOV-0): Hollow Stem Auger D11Bit si-T; e: 6' a[ xjer � Taal Derlhof e(dab: 15,5 feet bgs Grill Rg TyDe: Trailer Rig GAr�1a Calira�tor Boretee kpi)-h1zv' �eafaocEkmAb Fla-m-cr Data: WA c�ou,cr,al r Lem!: Not Encountered 1 Sanolil-o AJeL "s): SPT 14010, 3fr' drop rope 1 BOM`L' Et+-ul: Bentonite Chi LcatheadI 370 iwSouth, Federal WaY, Washington �•-�.�:� ..er:c. LyAkl. 1tA%011 PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Project Name: Federal Way Advance Auto Paris Boring No.: B-2 Project Number: 2015-145 ® I M Sheet 1 of 1 Client: Cadence Development, LLC RILEYGROUP DstE(s) oaie_d: 101142015 Lo99?d Di.. ELW I sham coix+ilions. Asphalt Dafing rouiod(s): Mow Stem Auger mi at SkLvTyx: 6" auger Tzar DDrth or ecmlpb: 16.5 feet bgs F Dril 69 Tpx: Traiar Rig DEN caimor Boretec "'1' °OaT " WA sufaoc FJerali�n: Gourct.�alerLet�.J:NotEncotmtcred se,=rMkiewJ(s):SPT Hammer Data:14D1b.30"drop,ropeand cathead eomrlee Back : Bentonite Chips Lmatiat 33370 Pacific Highway South, Federal Way, Washington of u o A o a 7 � I424rj 5?.6 56 PACLAN D MATERIAL DESCRIPTION K vmrrnxFied ro_k bay — — — ImvYnsilk• SN [77 v,8t, s nie qmvel, m_dum :kx-m. m?izt w. darx to NEt Tir. nd_yG"it,, In:. PS'290i1.'� tYxyNE; �ilipA, lii1�11 Project # 10518004 5 r lit Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Project Name: Federal Way Advance Auto Parts Project Number: 2015.145 ■ Boring No.: B-3 Client: Cadence Development, LLC �� Sheet 1 of 1 D@Ws) o &i J: 10H4I2 .. IAV-1f By: ELW i sUfam Carriitio.1% Asphalt D wn3 kieo ems): Hopow Stem Auger Drit Bit S zcTyae: 6" a Tcial��4horP�xeta�: 11 foctbgs Drill Rig Tye: TraikxRig Dril", Ccnu-ac,-BOrLtL ?„�t-,roxnnale ScHa El :s►;r. WA G�eurrJastcrL�el: Not Encountered I ss—k-oty wD*s): sPT 140lb.30" drop, r tiann�r Data : catheact p � and BaCa: Bcntottite Chips Location 33370 Pacific H' tglnvaYSouth rcderalWaY,Washinutan PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Project Nance: Federal Way Advance Auto Parts a I M Boring No.: B-4 Project Number: 2015-145 1 LM Sheet 1 of 1 Client: Cadence Development, LLC RIOGROOP Datgs)D51ed: 10/14M15 LowaBy: ELW I aufacecordaior' Aspha6 Dr1k-@ K1emKs): Hollow Stem Augcr. l DM U smm,-Pge: 611 augDr I Twl Dmit of B-reFDle: 16.5 feet bgs Grit rg 1�': Trailer Rig `mot callracix Boretec 'S� �Aon: WA G-ourctsatx Le el: Not Encountered I sarrrb-Ok�u�ts): SK I W-wrix Data: 1401b. 30"drop, rope and catiWd BwJrAe eackfill: Bentonite Chips I Location: 33370 Pacific Highway South, Federal Way, Washington ti c � � 2 a> m y E j MATERIAL DESCRIPTION f � ure- 2^asrys�•r�Lrcruslrstrxscl�ase a.i B�,M 5iry SeV,DvAd i xnlc-�favrl, mtxiaim cierac. frciSL r .� -&,-, X- ^Di:! b'tiLL a] a Yx, 4 ►3 5^:I CraySiy SAiJp.swt s�^1e ga.'cT.vr.`Ycr"!aG g1761 lG[�'til till) — — — 5 I-- - BC-Con1es-Dist LDML - 87;11" . 8Cm7 twurow Ry 1•a V .-� PACLAN D 17522509M' 4V 'E. N#KA. WIN%)11 Project # 10518004 Page 31 I Advance Auto Parts Preliminary Technical Information Report p Federal Way, Washington Project Name: Federal Way Advance Auto Parts Project Number: 2015-145 ■ Boring No.: B-5 Client: Cadence 17eveEapment, LLC RILEYP7 Sheet 1 of 1 Doles) D ikd: 101141201,5 Logged Bsr- i_Lw Surface CoIxiyans Asphalt Drlr% McMksj: HOEEE� NO Bit S;"ize: V auger TotalCrrAhorP�re aIM: 10.5footbgsDr��17�TY e: TraileDrltdijcxmxtx Borctec 4Ya�enxr Grouai.aaacr L-LA: Not Encountered Sanrrar3 MM,0*0: SPT S�eFa a EkR.�iati NIA +RwnmerDaia:ca&wd "dmA'topeand B vt le eac�ru: BetttoniM CFups LocaGOn: 33370 Pacific HaYSoutFt, Federal Way. WashinaMn PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Project Name: Federal Way Advance Auto Parts Project Number: 2015-145 ■ �M Boring No.: B-6 Client: Cadence r]—Iopment, LLC RILE BR IN Sheet 1 of 1 Dat4sjD9eJ: 10/14/2015 'Lana By- ELW SL Xe Co dito - Asphalt DriWlttl f(sj: HDROW Stem Auger Dril at S'¢eT.Ype: B' auger Total D_N' of BOMID : 10.5 feet bgs DrilRigT}-: Trailer Rig ' Drirut i co)vaaA r. Boretec Aarr.,uexnxe SurraccfXvy�n WA aou rrvAerLeeel: Not Encountered ' Sa=rMM2U11J(s): SPT 7401b. 30 dm IlacmxrData: cathoad A. rope Bo,M )OL- ant: &IUMite Chips I Lo k— 33370 Pacific Hi ghway South. Federal Way, Washington —I -. 1Vka. �r,`ri�i011 PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Project Name: Federal Way Advance Auto Parts Project Number: 2015-145 ■ M Boring No.: B-7 Client: Cadence Development, LLC E!" Sheet 1 of 1 Dzaq-R) D k-J: 10/14/2015 Lo.?.i B;: ELW 5urtace CarKt7ixs Asphalt Drir"D k'cL' Ksj: HopoW Stem Auger Dnil Bit Sm lry e: 6" auger TaLal *IxhoFBaM!*: 10,5 feet kos Dr7I Ra Ty e: Traier Rig Dr�rna Cai!r ctor. Boretec Afi- irvaa c ou xtJat rt eel: Not Encountered Sznrrurl Aden SPT 740 ftr.30" dn7 .rope and Fla^r o Data P r ea so: Bcntonitc Chi eathead B ' L=!im: 33370 Pacific Highway South, Federal Way. Washimi— PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Project Name: Federal Way Advance Auto Parts I M Boring No.: B-8 Project Number: 2015-145 11116� Sheet 1 of 1 Client Cadence Development, LLC RILEYGROUP Daux-) D�enl: 10H412015 I Loag~i Bp- ELW Lutxe Corriifions Asphalt Drirna loowc (s): Follow Stem Auger I DrM EL Sbr rya,,: 6" auger I Taal CMlior eaeipW. 15,25 feet bgs Dal RijTy,*: Trailer Rig I Dilruil Convactx. Boretec I " .�_ WA o-ou�rl'ra r Lc-M: Not Encamtered S=.nufull F. L'�rJ(s): SPT Ha^:lnxr Data: cathead 0'• drop, rope and BordrLe ea:,M: Bentonite Chips Lxag= 33370 Pacific Highway South, Federal Way, Washington PACLAN D 17,322:7otK,Jl: <n�NE: 7�Ytw9, VIA %011 Project # 10518004 W S 7 3 r a Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Project Name; Federal Way Advance Auto Parts Project Number: 2015.145 ■ 10 Boring No.: B-9 Client: Cadence beveloprnent, LLC 7RILEYGROUPk"Sheet 1 of 1 Datr{sj D5®ed: 10H412015 Low i ey. ELW Surtax Go;railgns: Asphalt D� irA3 Mews}: HogoW Stem Auger GAl BiL S¢�Trpe: 6 , LW T II oerxh or BaeiDrn: 15.33 feet bgs DfilRkj T}•Lc:TrallcrRig IDIAt1.1G711iLJf Bolatec �T+bxYliE rraoe ELes�[ar WA Grou-aWCeLe—M: Not Encountered SanrlhOWL',aXsy: SPT I Ha-ncrDala; 140ib.30"drop, rope and d eorclrb E:JM: Bcrnonite Chips { LocaU--: 33370 Pacific Hk_owmy South, Fcdcral cathcv Way. Washin4tlon PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report p Federal Way, Washington Project Name: Federal Way Advance Auto Parts Project Number: 2015-145 Boring No.: B-10 Client• Cadence Development, LLC ItAY� Sfleet 1 of 1 DaIE{s)Dri@esl: 1011412015 + tarr.:l Bye F1W sirtam COJM *-t ' Asphalt D'I" r*'L' ks): HopoW Stem AtSor Dnu FM Sim, 6' at _ � Taal Delxhof Boreiob: 15.5 feet begs Dril MgT5-: Trailer Rig DrA-Q Caivaaor. Boret,ec Aal minime WA xHaoeEkur, .: Grou xi aaterLe rv: Not Encamtered Sanrdui3 F.ieua�lc? SPT 140 fb.30" ft Ha^��y-Crata: P• rope BOm+ = : Bentonite Chi cathand Ps ' LO.akn: 33370 Pacific HijWay south• federal Way. W—h*,.. .., PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Project Name: Federal Way Advance Auto Parts Project Number: 2015-145 ■ M Boring No.: B-1 1 Client: Cadence [7evelo , ,- prnent, LLC �M YGR011P Sheet 1 of 1 Ntgs) DJ"- : 10/14/2015 I Logged By., ELW + airfaLe corn kiomK Aspl It D"" WL'-(s): Ho6ow Stem Alger 1 DOI R s¢eType: 6" at Eger TTastCeixhoreactaL-:15.5fcrtbo. Drit Rig Type: Trailer Rig DrUrn Ca M-c Boretec Alpoxhiae &�rfa�FJCrdlgn; WA G-ou1-d,kAerLeet: Not Encountered 1 Set V1k"Q F,1CL'd(5): SPT 94t1 Fb. 30" drop, rope and Fla"i�-Data: cathead Bordcb ea;�ru: 6entonite chips Casual 33370 PaciHC H' nva �Y South, FL'deral Wav, Washington PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington Project Name: Federal Way Advance Auto Parts Project Number: 2015-145 ■ ■ 0 Boring No.. B-12 Client: Cadence Development, LLC ' �� i► RSheet 1 of 1 Datgs)Df)'0W: 10H412015 ! L-W1 ey_ ELW 30fweCo;xiilqm Asphalt min? met--ks}: Hollow Stem Auger � DrM &t Sb�,Trr: 6--auger TaUIDetMhofPc�!a�: 11 feetbgs DrilRigTyx:TralkrRig DrIF")coltrwor.Borew, a i tc 5uiati,Ej, a irr. WA c ou�l su,r Lem: Not Encountered , sa rrru7t h � adcs}: SPT lianme: Data.- 140 430" drop. rope and caihead BOOM, ��: Bentonite Chips Laca6ar 33370 Pacific H' aY South, Federal Way, Washlnaton PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report p Federal Way, Washington Project Name: Federal Way Advance Auto Parts Project Number: 2015-145 M Key to Log of Boring Client: Cadence Develapment, LLC M� © E Sheet 1 of 1 1- 0 ' II o r L� 3 = 5 s a MATERIAL DESCRI..MCN z ��1,UMLf DES�,QI `J d[7evallcn ;seer): aevavot, (e>s�. rer0. � r-0ernti 1DWtlips-); DEng h feet 16L , gwnd strfarw. Reoo xxy xage ES detetnhed rased mS ,,y (e Ty,-*: Tyrteaf sop s&-emlecdlectedat the depttin hLer aI a rats hfena3 s h FWe:+&q* roccA rwcyrw .d (p t*,g 5l7a n. �4 Sam -No M: SaTM wnwj:alkn FFJ? Y3'5CS %7L'Ct L15CS a roal c(L tes su dace maleml. 5 Sar ,*V Resi tmze. DbAsY,: N t g C Wtk -3= r'TP� tc dDOCUOn 6f tie °i1�C7' Xe nt2=,yW sa' F92r one hat (Or dishys:,MTI beyand septaadd &K-'I exotntered �V tteh-r— kient kd (n thettcrkkr� Fxerval ❑9 i fATERiA �ESCR[PTltaU De xfort drrurerti! e-cnu7,�ed Afay hCltie oars�tezy, tYtoisrxe. aofor.a'xi athertl•Sryb}},� t2M. L hblswre ("',): Motcttre, eked as a slater contem Q S CFCht Rte� lests 16a5SM=rO6h4y COMIR cco n;w kn WA CONS: Cne�dlm"hwl CcrSdkLAj n less L Uqw Lhnit,permit MMTMMLCAAMK1MD= ■ Asrttaltic Crete (4C) 9AF PC PlaSlkiy Index, percent SA SIe t a �3fysk Gra t sslrg pia a3asleve) Uc: U,ac„rtned QV,:, te�t.o:,. h bt WA: Sleae (phi[ ( stx� No. 2W Sie,e} C:' Vd'dl Spaded GRAVEL M) SILT. SILT .,;SAND, SANDY SLT iML) Silty SAID (SLi) CME.5.".nw*r '■Pitcher $c7 a --s k-%vi(at fines ordnjrAlD) et,rK same 2D unlhedsaiit -_ 3 f *C3D CBliForrva Kt brm *m , 2 g.l•-01,0D hbdiRW coakrnla Wrl?ta't55lh�s N Spool (Spo en- in rrterrrl : r� ai esttiLiv a SNZy Tti� sa earn bed head) (7 '�'•sdlk"t. — _ hderrt2t4'.ra:bti^nst.ca a t UeC�egi strata —?- Dueriri MUCL Lr-mwn data I: 5 cis tKxGn s are rasa Yt the Un�r f Sad Clla t Sfl t. ra I FH f iPtb�s mcyh E Cm nrzfC�xi bref rt the CfL,L (� CeSCW. ani swum k-les are irnerryetivc. and win] Wubgic Charges a' be ` C�esp c{irrs an t tan txy etxA� a 6y nt the sC.Cy r 9.1>sLrfxe :txtiiians nL Cd inr kca4tir, or tinm Wri bz$Lbr arcs at Ute dr- Lhe l3wres &'e2 adan.,c-L T*, are net waTantcd to to mM--sap ati e TN+:ty:!: C.vr3t Lk. 17a'.2?ri: k# :'fir "f_, Z l��• 1 �'lt;�Jl 1 PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington THE RILEY GROUP, INC. 17522 Bothell Way NE PHONE: (425) 415-0551 Bothell, WA 98011 FAX: (425) 415-0311 GRAIN SIZE ANALYSIS ASTM D421, D422, D1140, 02497, D6913 LE Federal Way Advance Auto Parts PROJEt7:iE- PROJE. 2035.145 SAMPLE ID/TYPE B-3 TECH/ATE CM SAMPLE DEPTH s MasturelTnlal 101201201s DATE RECEIVEDWATEENT{Delivered WeTare (gm) (wl) 415.8Wt Wei h f SamrrcoWt Dry Tare (gm) [w2) 406.7 Weight Of Sample (gm) 406.7 Weighe (gm) (w3] Tare Weight (gm) 15 7 m (g ) (w4=wl.w2) I5.7Weighter 9.1 tal Dry Wei ht {gml Weight Soil (gm) (wS=w2-w3) 391.0Moistuteni S VE IS (%) f+v41w5)'100 2 Cumula ive Wt Ret W[-Tare %Retained 9G?RS5 % COBBLES 0.0 -Tare k (100-%rat) % C GRAVEL 26.1 12.0" 3.0- 15.7 0.00 0.00 100.00 cobbles % F GRAVEL 34.6 2.5" 157 0.00 0.00 100.00 coarse gravel % C SAND 11.7 2 01 coarse gravel % M SAND 13.7 1.5" 15.7 0.00 coarse gravel % F SAND 10.4 1.0" 0.00 100.00 coarse gravel % FINES 3.4 % TOTAL 1110 0 0.75" 117.8 102.10 26 1] 73. 19 coarse gravel fine gravel D10 (mm) 0.3 0 50' 0.3715" 197.0 181.30 46.37 53.63 fine gravel fine gravel D30 (mm) 2.4 fi4 253.2 237.50 60.74 39.26 coarse sand 060 (mm) 10.3 410 299.1 283.40 72.48 27.52 medium sand Cu 34.3 Cc 1.9 1120 1140 352.8 337,10 86.21 13.79 medium sand fine sand tf60 sf300 387.0 371.30 94.96 5.04 fine sand fine sand 0200 393.6 377.90 96.65 1 as C-1 % 100 90 BO P 70 A 60 5 5o S 40 30 1 20 N 10 G 0 1( _-.. lu 1 Grain size in millimeters DESCRIPTION Well graded sandy GRAVEL with trace silt USCS G4': d For: Reviewed By: KMW Development uc PACLAN D PAN 406.7 12• 3• 7 1•.7S' �1In Kr RILEYGROUP Project # 10518004 0.00 0.1 0.01 0.001 Page 31 Advance Auto Parts Preliminary Technical Information Report Federal Way, Washington THE RILEY GROUP, INC. 17522 Bothell Way NE PHONE: (425) 415-0551 Bothell, WA 98011 FAX: (425) 415-0311 GRAIN SIZE ANALYSIS - ASTM D421, D422, D1140, D2487, D6913 PROJECTTITLE FedcraE Way Advance aura Parrs PROJECT NO. 2015-145 SAMPLE ID/TYPE 6.6 TECH/T! !: DRI CM SAMPLE DEPTH z.s' 10/20/2015 DATE RECEIVED1UILsJ2ats WATER CONTENT Delivered Moisture Total Wei ht Of g5 Snrn to Uti d ForSiev Corrected Fnr H rR[O iP.[ Mais Wt Wet Soil & Tare {gm) (wl] 516.0 Wt Dry Soil & Tare (gm Weight Of Sample (gm) e95.5 (w2) 495.5 Tare Weight (gm) 15.9 Weight of Tare (gm) (w3) ❑ Weight of Water (gm) 1� iw5) Total Dry Weight (gml 479.6 {w4=wl-w2l 20.5 iE ANA SIS Weight of Dry Soil (gm) (w5=w2-w3) 479.6 % Moisture Content CUmulative ( I (wdlw5)' lOD d Wt Ret Wt-Tare iaRelained) % PASS %COBBLES 0.0 'Tare -M UIU.Sw } i�o} (300.9Gret) %CGRAVEL 12.0- 15.9 0.00 0.00 100.00 cobWes 5.3 3.0" 15.9 0.00 % F GRAVEL 0.00 100.00 coarse gravel 29.4 2.5' %CSAND 13.4 2,0, soarsegravel roarse gravel % M SAND 16.9 1.5' 15.9 0.00 O.DO %FSAND 16.0 100.00 coarse grave: 1.0" coarse gravel % FINES 19.1 0.75" 41.3 %TOTAL 100.0 25.40 5.30 94.70 fine gravel 0-50' fine gravel 0.375` 111.019.8380 D30 (mm) ka 182.2 166.66.30 3434.6767 .17 fine gravel 65.33 coarse sand 060 (mm) D30 (mm) p1Q 246.4 230.50 48.06 65.94 medium sand >i20 Cu mednlm sand 7140 327.4 311.50 64.95 35.05 Imesand Cc H60 flne sand 9100 380.5 364.60 76.02 23.98 Ime sand 9200 403.9 388.00 80.90 19.10 fines PAN 495.5 479.60 100.00 0.00 sill/clay 100 12 3- 1 V 75' .375' 04 910 N20 #40 bro m100 a200 90 so P 70 A 60 s SO 40 30 k N 10 i G 0 I i 1000 100 10 1 0.1 0.01 0.001 Grain size in millimeters DESCRIPTION Saty $AND with gravel USCS Sivl Prepared For; Reviewed By: KMW Code- 'Itwlapmcn r LLC a L7 RILEYGROUP PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report fP Federal Way, Washington THE RILEY GROUP, INC. 17522 Bothell Way NE PHONE: (425) 415-0551 Bothell, WA 98011 FAX: (425) 415-0312 GRAIN SIZE ANALYSIS ASTM D421, D422, D1140, D2487, D6913 PROJECTTITLE Federal Way Advance Auto Parts PROJECT NO. ZOIS-145 SAMPLE PE g_g TECHjTEST DATE CM SAMPLE DEPTH Z.S. WATER CONTENT Qeliver¢d Moisture 10J20/2015 DATE RECEIVED Total Wei ht OI Sam le Used For Siev Corrected For�011rn2,ro W[ Wet Soil &Tare (gm) Iµ,ll Soo R fi roseo is Mni. Wt Dry Soil 8, Tare (gm) Weight Of Sample (gm) 559.4 Weight of Tare (gm) (tv�1 559.E Tare Weight (gm) 15.7 Weight of Water (gm) Iw3) 15.7 ltv6l Total Dry Weight If (w4 w1•w2} 2sm 543.7 Weight of Dry Soil (gm) SIEVE ANA. ty515 (w5=w2-w3) 543.7 Moisture 00 Con ISSJ {w4/w5)•]5 WtRet Wt-Tare 94CumRerained ulagi %PASS %COBBLES +Tare e11 61,x 0.0 12 0" 15 7 ..=-.�'2i (ip0-%ret) % C GRAVEL 6.5 15.7 0-00 0.00 3.0" 100.00 ro6ble5 % F GRAVEL 26.0 2.51 0.00 0.00 100.00 coarse gravel %[SAND 112 20„ coafsegravel % M SANG Lc 1 coarse gravel %FSAND 1.S" 15.7 0.00 0.00 100.00 coarse gravel 20.8 I.0" %FINES �04 coarse gravel %TOTAL 0.75"50" 51.1 3540 6.51 100.0 0.50" 93.49 fine gravel 0.375" 123.9 fine gravel D10 (mm) 108.20 19.90 90.10 fine gravel D30 (mm) #4 192.4 176.70 32.50 67.50 coarse sand D60 (mm) # IO 253,1 237.40 43.66 420 56.34 medium sand Cu#4.3 medium Sand 0 335.3 31960 58.79 41.22 finesand #fit 7t300 414.4 fine sand 398.70 73.33 26.67 line sand 4200 448.6 432.90 79.62 20.38 fines PAN 559.4 543.70 100,00 0.00 silt/clay 100 12, 3' 2" 1-.75' .375• #4 410 020 040 090 #100 V1200 .90 so - -- --...... I I A 60 I _ S Sp 5 40 30 I l 20 1 N 10 G 0 1000 100 10 1 0.1 0.01 0.001 Grain size in millimeters DESCRIPTION Silty- SAND with gravel USCS 5�n Prepared For: Reviewed By: KMW Cadence 0evelopmem ELC l� 11 ll� RfLEYGROUP PACLAND Project # 10518004 Page 31 I Advance Auto Parts I I Preliminary Technical Information Report Federal Way, Washington _I Appendix D - Stormwater Quality -� information PACLAND Project # 10518004 Page 31 Advance Auto Parts C`'ALr TECH ENGINEERED SOLUTIONS Preliminary Technical Information Report Federal Way, Washington Prepared by Mike Gillette on May 27, 2016 Size and Cost Estimate Advanced Auto Parts — Stormwater Treatment System Federal Way, WA Information provided: • Presiding agency = Federal Way, WA I Water Quality Flow Rate (tfs) 0.176 - Peak Flow Rate ids) 1 79 0.176 -- — — Number of cartridges 11 1.79 ~� Cartridge flow rate S8pm1 7.5 - 6 Media type ZPG 15 Structure size 96" Manhole SF ~ 72" Manhole Can Approximate Price $38,250 $ 27,300 Assumptions: • Media = ZPG Cartridges for first facility. CSF for second facility • Cartridge flow rate = 7.5 gpm for first facility, 15 gpm for second facility • Drop required from rim to outlet = 2,3' minimum Size and cast estimates: The StormFilter is a flow -based system, and is therefore sized by calculating the peak water quality Row rale associated with the design storm. The water quality Row rates were Calculated by the consulting engineer using KCRTS and were provided to Contech Engineered Solutions L L C for the purposes of developing this estimate. The StormFilter treatment train for this site was sized based on the above water quality Row rates. To accommodate these flow rates, Contech Engineered Solutions recommends using SlormFilter manholes with ZPG media for basic treatment, and CSF media for enhanced treatment (see attached detail)- The estimated cost of these systems is shown in the above table; these estimates include compiele systems delivered to the job site. The final system cast will depend on the acluaf depth of the units and whether extras like doors rather than castings are specf8ed. The contractor is responsible for setting the StormFilter manholes and all external plumbing. Typically the precast StormFilters have internal bypass capacities of 1.8 cfs. If the peak discharge off the site is expected to exceed this rate, we recommend placing a hfgh-flow bypass upstream of the StormFilter system. Contech Engineered Svfu[ions could provide our high -flow bypass, the SlormGate, which provides a combination final weir -orifice control end on t e limit the Row lv the SlOaTiFfller- The estimated cost of this structure is $4,500, The Tina] cost would depend on the actual depth and size of the unit - final Contech Engineered Solutions LLC 11835 NE Glenn widing or., ponland OR 97220 www.conteches.com Page 1 of 1 Toll-free:800.548,4667 Fax:600-561,1271 TS-P027 PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report C- NTFCH ENGINEERED SOLUTIONS CONTECH Stormwater Solutions Inc. Engineer. Date Site Information Project Name Project State Project Location Drainage Area, Ad Impervious Area, Ai Pervious Area, Ap % Impervious Runoff Coefficient, Re Water quality flow Peak stone flow Filter System Filtration brand Cartridge height Media Type Specific Flow Rate Flow rate per cartridge Federal Way, Washington Determining Number of Cartridges for Flow Based Systems MSG 5/27/2016 SFMH1 Advanced Auto Parts Washington Federal Way 1.82 ac 0.98 ac 0.84 54% 0.53 0.176 cfs 1.79 cis StormFilter 18 in ZPG 1.00 gpm/ft` 7.5 gpm SUMMARY Number of Cartridges iT W006 CONTECH Stormwater Solutions Conte chstorrnwater, corn 1 of 1 PACLAND Project # 10518004 Page 31 Advance Auto Parts Preliminary Technical Information Report fp Federal Way, Washington C:: NTECH ENGINEERED SOLUTIONS CONTECH Stormwater Solutions Inc. Engineer. Date Site Information Project Name Project State Project Location Drainage Area, Ad Impervious Area, Ai Pervious Area, Ap % Impervious Runoff Coefficient, Rc Water quality flow Peak storm flow Filter System Filtration brand Cartridge height Media Type Specific Flow Rate Flow rate per cartridge SUMMARY Numi}er of Cartridges 02006 CONTCCH Stormwater Solutions co nt a chstorm%vate r. com Determining Number of Cartridges for Flow Based Systems MSG 5/27/2016 SFMH2 Advanced Auto Parts Washington Federal Way 1.82 ac 0.98 ac 0.84 S4% 0.53 0.176 cfs 1.79 cis StormFilter 18 in CSF 2.00 gpm/ft` 15.0 gpm 1 of 1 PACLAND Project # 10518004 Page 31 Advance Auto Parts C=a►► NTECH ENGINEERED SQLUTIoNS August 22, 2016 Preliminary Technical Information Report Travis Cheshire Pacland 1505 Westlake Ave N., Suite 305 Seattle. Washington 98109 RE: StormFilter Review, Advance Auto Parts — Federal Way Federal Way, Washington Contech Engineered Solutions LLC has reviewed the plans showing the StormFilterstorrnwater Ireatment System for the Advance Auto Parts project in Federal Way, Washington The plans were prepared by Pacland Engineering. This appears to be a good application for the StormFilter. The designer reports the following site information: Water Quality �Flow Rat- cis _._-- Peak Flow Rate (Gfs) 0.276 0.176 Number of cartridges 1 79 1.79 Cartridge flow rate {8pm] 11 — 6 Media type 7.5 15 Structure size ZPG 96 Manhole CSF 72" Manhole Since the internal bypass rapacity of the Manhole StormFilter is 1.8 cis shown on the plans; a separate high flow bypass Struct, the systems may be used online as ure is not required. The systems appear 10 be constructible and the horizontal configuration of the inlet pipes and outlet pipes are acceptable for the StormFilters speciiled. The vertical separation between the inlet and outlet pipes provide the Prescribed drop required far the inter cartridges to operate The lton of the StormFilters on the site appears to maintenance activities. oca allow adequate maintenance access and the inside height of the units will provide sufficient clearance for In summary, the StormFilters are expected to operate in accordance with Contech Engineered Solutions' design intent. Please note that Contech Engineered Solutions has not reviewed the hydraulics of the collection system upstream or downstream of the Filters. Please do not hesitate to email if you have any questions or require more information. Sincerely, &A W& Mike Gillette Designer— Stormwater Products Contech Engineered Solutions, LLC mgillette@contec hes.com 02012 Contoeh Engineered Solutions LLC �+ c hES.00m 11835 NE Glenn Widng Dr„ Portland OR 97220 Toll -free: 800-548.4667 Fax; 800,561.1271 Page 1 of 1 TS-PO52 PACLAND Project # 10518004 Page 31 PERMIT #: 16-103450-00-CO ADDRESS: 33370 Pacific Hwy S PROJECT: New Retail Building ADVANCE AUTO DATE: 7118116 Construction Stormwater General Permit Stormwater Pollution Prevention Plan (SWPPP) for Advance Auto Parts RECEIVED JUL 18 2016 Prepared for: CITY OF FEDERAL WAY The Washington State Department of Ecology CDS Northwest Region Perm ittee / Owner Cadence Capital Investments, LLC Developer Cadence Capital Investments, LLC 33370 Pacific Highway S Operator / Contractor TBD Certified Erosion and Sediment Control Lead (CESCL) Name Organization Contact Phone Number TBD TBD TBD SWPPP Prepared By Name Organization Chris Flyckt PACLAND SWPPP Preparation Date July 15, 2016 Project Construction Dates Activity /Phase Start Date Site Construction 9/13/16 Contact Phone Number 206.522.9510 End Date 2/28/17 Table of Contents 1 Project Information ........................... 1.1 Existing Conditions .................................................................................................... 4 1.2 Proposed Construction Activities.........•...-...-••...^.......'...'-......'.".."'.......�..'.'.��"�� 4 ...................... 2 Construction Stormwater Best Management Practices(BMPs)........................................... 6 2.1 The 13 Elements ............... 2.1.1 Element 1: Preserve Vegetation / Mark Clearing .. 6 Limits........................................ 6 2.1.2 Element 2: Establish Construction Access ....................... 2.1.3 Element 3: Control Flow Rates ................................... 2.1.4 Element 4: Install Sediment Controls ............. 2.1.5 Element 5: Stabilize Soils ................ 2.1.6 Element 6: Protect Slopes...........................................11 ......... 2.1.7 Element 7: Protect Drain Inlets ...................................... 2.1.8 Element 8: Stabilize Channels and Outlets..........................................................13 2.1.9 Element 9: Control Pollutants.............................................................. 2.1.10 Element 10: Control Dewatering................................................. 2.1.11 Element 11: Maintain BMPs................. 2.1.12 Element 12: Manage the Project..........................................................................18 2.1.13 Element 13: Protect Low Impact Development (LID) BMPs ................... 3 Pollution Prevention Team ......... 4 Monitoring and Sampling Requirements..................'.'.'...'.'..."..'.'..,.'.,."....,'.,.,.,...'.,...."...22 4.1 Site Inspection ..........................-...........................................................23 4.2 Stormwater Quality Sampling....................................................................................23 4.2.1 Turbidity Sampling..........................................................................._...23 4.2.2 pH Sampling................................--.............................................................23 ..........................25 5 Discharges to 303(d) or Total Maximum Daily Load (TMDL) Waterbodies ..................... . ...26 5.1 303(d) Listed Waterbodies..........................................................................................26 5.2 TMDL Waterbodies............. 6 Reporting and Record Keeping..........................................................................................26 .......................................................................................27 6.1 Record Keeping 6.1.1 Site Log Book ............................-..................................................................27 6.1.2 Records Retention.... ..........................................................................27 6.1.3 Updating the SWPPP..........................................................................................27 6.2 Reporting................................................................................................................ 27 6.2.1 Discharge Monitoring Reports..............................................................................28 ...........................................28 6.2.2 Notification of Noncompliance .................................. Page I 1 List of Tables Table 1 — Summary of Site Pollutant Constituents..................................................................... 4 Table2 — Pollutants..................................................................................................................14 Table3 — pH -Modifying Sources...............................................................................................14 Table4 — Dewatering BMPs......................................................................................................16 Table5 — Management.............................................................................................................18 Table 6 — BMP Implementation Schedule.................................................................................19 Table7 — Team Information......................................................................................................22 Table 8 — Turbidity Sampling Method........................................................................................23 Table9 — pH Sampling Method.................................................................................................25 List of Appendices Appendix/Glossary A. Site Map B. BMP Detail C. Correspondence D. Site Inspection Form E. Construction Stormwater General Permit (CSWGP) F. 303(d) List Waterbodies / TMDL Waterbodies Information G. Contaminated Site Information H. Engineering Calculations Page 12 List of Acronyms and Abbreviations Acronym / Abbreviation Explanation 303(d) Section of the Clean Water Act pertaining to Impaired Waterbodies BFO Bellingham Field Office of the Department of Ecology BMP(s) Best Management Practice(s) CESCL Certified Erosion and Sediment Control Lead COZ Carbon Dioxide CRO Central Regional Office of the Department of Ecology CSWGP Construction Stormwater General Permit CWA Clean Water Act DMR Discharge Monitoring Report DO Dissolved Oxygen Ecology Washington State Department of Ecology EPA United States Environmental Protection Agency ERO Eastern Regional Office of the Department of Ecology ERTS Environmental Report Tracking System ESC Erosion and Sediment Control GUILD General Use Level Designation NPDES National Pollutant Discharge Elimination System NTU Nephelometric Turbidity Units NWRO Northwest Regional Office of the Department of Ecology pH Power of Hydrogen RCW Revised Code of Washington SPCC Spill Prevention, Control, and Countermeasure su Standard Units SWMMEW Stormwater Management Manual for Eastern Washington SWMMWW Stormwater Management Manual for Western Washington SWPPP Stormwater Pollution Prevention Plan TESC Temporary Erosion and Sediment Control SWRO Southwest Regional Office of the Department of Ecology TMDL Total Maximum Daily Load VFO Vancouver Field Office of the Department of Ecology WAC Washington Administrative Code WSDOT Washington Department of Transportation WWHM Western Washington Hydrology Model Page 13 1 Project Information Project/Site Name: Advance Auto Parts Street/Location: 33370 Pacific Highway S. City: Federal Way State: WA Zip code: 98003 Subdivision: N/A Receiving waterbody: Hylebos Creek 1.1 Existing Conditions Total acreage (including support activities such as off -site equipment staging yards, material storage areas, borrow areas). Total acreage: 1.82 Disturbed acreage: 1.33 Existing structures: 0.12 Landscape 0.87 topography: Drainage patterns: Moderate to steep slope to South. Existing Vegetation: Landscape and an area of mature native trees and shrubs/grass. Critical Areas (wetlands, streams, high erosion None noted. risk, steep or difficult to stabilize slopes): List of known impairments for 303(d) listed or Total Maximum Daily Load (TMDL) for the receiving waterbody: N/A Table 1 includes a list of suspected and/or known contaminants associated with the construction activity. Table 1 — Summary of Site Pollutant Constituents Constituent Location Depth Concentration (Pollutant) No known pollutants L 1.2 Proposed Construction Activities Description of site development (example: subdivision): The proposed project will consist of a boundary line adjustment on the 1.82 AC site, whereas the south lot will be developed to include an approximately 7,000 SF Advance Auto Parts store, associated parking/drive aisles, landscape, storm facilities, and associated utilities. Description of construction activities (example: site preparation, demolition, excavation): Page 14 A portion of the site will be cleared and grubbed and graded to design surface elevations to create building pads and subgrade for parking areas and sidewalks. The site will then be paved and other disturbed areas will be stabilized with landscaping/ground cover and mulch. A portion of mature trees to the East of the site will be protected to remain and various portions of existing surface paving will remain in place. Description of site drainage including flow from and onto adjacent properties. Must be consistent with Site Map in Appendix A: The site slopes moderately from north to south. There is limited flow/run-on from adjacent properties. Surface water is collected by a series of catch basins and conveyed to the discharge point in the southeast corner of the site via underground pipes to the city's stormwater system within S 3361h St. This is consistent in the developed condition however stormwater will be routed through two stormfilter facilities providing basic and enhanced treatment. Description of final stabilization (example: extent of revegetation, paving, landscaping): Final stabilization will consist of paving (concrete and asphalt), landscaping, building, and maintenance of existing native grass areas. Contaminated Site Information: Proposed activities regarding contaminated soils or groundwater (example: on -site treatment system, authorized sanitary sewer discharge): There are no known contaminants on site. As part of this project, the proposed building will be connected to public sewer within Pacific Highway. Page 15 2 Construction Stormwater Best Management Practices (BMPs) The SWPPP is a living document reflecting current conditions and changes throughout the life of the project. These changes may be informal (i.e., hand-written notes and deletions). Update the SWPPP when the CESCL has noted a deficiency in BMPs or deviation from original design. 2.1 The 13 Elements 2.1.1 Element 1: Preserve Vegetation / Mark Clearing Limits To protect adjacent properties and to reduce the area of soil exposed to construction, the limits of construction will be clearly marked before land -disturbing activities begin. Trees that are to be preserved, as well as all sensitive areas and their buffers, shall be clearly delineated, both in the field and on the plans. In general, natural vegetation and native topsoil shall be retained in an undisturbed state to the maximum extent possible. The BMPs relevant to marking the clearing limits that will be applied for this project include: High Visibility Fence and Preserving Natural Vegetation. Alternate BMPs for marking clearing limits are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix D). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix D), the Certified Erosion and Sediment Control Lead will promptly initiate the implementation of one or more of the alternative BMPs listed in Appendix C after the first sign that existing BMPs are ineffective or failing. Inspect flagged and/or fenced areas regularly to make sure flagging or fencing has not been removed or damaged. If the flagging or fencing has been damaged or visibility reduced, it shall be repaired or replaced immediately and visibility restored. If tree roots have been exposed or injured, "prune" cleanly with an appropriate pruning saw or lopers directly above the damaged roots and recover with native soils. Treatment of sap flowing trees (fir, hemlock, pine, soft maples) is not advised as sap forms a natural healing barrier. If the fence has been damaged or visibility reduced, it shall be repaired or replaced immediately and visibility restored. Page 16 2.1.2 Element 2: Establish Construction Access Construction access or activities occurring on unpaved areas shall be minimized, yet where necessary, an access point shall be stabilized to minimize the tracking of sediment onto public roads, and street cleaning shall be employed to prevent sediment from entering state waters. All wash wastewater shall be controlled on site. The specific BMPs related to establishing construction access that will be used on this project include: Stabilized Construction Entrance/Exit. Alternate construction access BMPs are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix D). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix D), the Certified Erosion and Sediment Control Lead will promptly initiate the implementation of one or more of the alternative BMPs listed in Appendix C after the first sign that existing BMPs are ineffective or failing. If the entrance is not preventing sediment from being tracked onto pavement, then alternative measures to keep the streets free of sediment shall be used. This may include replacement/cleaning of the existing quarry spalls, street sweeping, an increase in the dimensions of the entrance, or the installation of a wheel wash. Any sediment that is tracked onto pavement shall be removed by shoveling or street sweeping. The sediment collected by sweeping shall be removed or stabilized on site. The pavement shall not be cleaned by washing down the street, except when high efficiency sweeping is ineffective and there is a threat to public safety. If it is necessary to wash the streets, the construction of a small sump to contain the wash water shall be considered. The sediment would then be washed into the sump where it can be controlled. Perform street sweeping by hand or with a high efficiency sweeper. Do not use a non -high efficiency mechanical sweeper because this creates dust and throws soils into storm systems or conveyance ditches. Any quarry spalls that are loosened from the pad, which end up on the roadway shall be removed immediately. If vehicles are entering or exiting the site at points other than the construction entrance(s), fencing (see BMP C103) shall be installed to control traffic. Upon project completion and site stabilization, all construction accesses intended as permanent access for maintenance shall be permanently stabilized. Page 17 2.1.3 Element 3: Control Flow Rates In order to protect the properties and waterways downstream of the project site, stormwater discharges from the site will be controlled. The specific BMPs for flow control that shall be used on this project include a Temporary Sediment Pond. Alternate flow control BMPs are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMPs) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix D). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix D), the Certified Erosion and Sediment Control Lead will promptly initiate the implementation of one or more of the alternative BMPs listed in Appendix C after the first sign that existing BMPs are ineffective or failing. In general, discharge rates of stormwater from the site will controlled where increases in impervious area or soil compaction during construction could lead to downstream erosion, or where necessary to meet local agency stormwater discharge requirements (e.g. discharge to combined sewer systems). Will you construct stormwater retention and/or detention facilities? X Yes ❑ No Will you use permanent infiltration ponds or other low impact development (example: rain gardens, bio-retention, porous pavement) to control flow during construction? ❑ Yes X No Sediment shall be removed from the pond when it reaches 1—foot in depth. Any damage to the pond embankments or slopes shall be repaired. Page 18 2.1.4 Element 4: Install Sediment Controls All stormwater runoff from disturbed areas shall pass through an appropriate sediment removal BMP before leaving the construction site or prior to being discharged to an infiltration facility. The specific BMPs to be used for controlling sediment on this project include: Silt Fence and Temporary Sediment Pond. Alternate sediment control BMPs) are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix D). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix D), the Certified Erosion and Sediment Control Lead will promptly initiate the implementation of one or more of the alternative BMPs listed in Appendix C after the first sign that existing BMPs are ineffective or failing. In addition, sediment will be removed from paved areas in and adjacent to construction work areas manually or using mechanical sweepers, as needed, to minimize tracking of sediments on vehicle tires away from the site and to minimize wash -off of sediments from adjacent streets in runoff. Sediment shall be removed from the pond when it reaches 1—foot in depth. Any damage to the pond embankments or slopes shall be repaired. Regular inspection of silt fence is required. Sediment shall be removed and filter material replaced as needed Page 19 2.1.5 Element 5: Stabilize Soils Exposed and unworked soils shall be stabilized with the application of effective BMPs to prevent erosion throughout the life of the project. The specific BMPs for soil stabilization that shall be used on the project include: Dust Control BMP and Temporary and Permanent Seeding. Alternate soil stabilization BMP(s) are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix D). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix D), the Certified Erosion and Sediment Control Lead will promptly initiate the implementation of one or more of the alternative BMPs) listed in Appendix C after the first sign that existing BMP(s) are ineffective or failing. In general, cut and fill slopes will be stabilized as soon as possible and soil stockpiles will be temporarily covered with plastic sheeting. All stockpiled soils shall be stabilized from erosion, protected with sediment trapping measures, and where possible, be located away from storm drain inlets, waterways, and drainage channels. West of the Cascade Mountains Crest Season During the Dry Season During the Wet Season Dates May 1 — September 30 October 1 — April 30 Number of Days Soils Can be Left Exposed 7 days 2 days Soils must be stabilized at the end of the shift before a holiday or weekend if needed based on the weather forecast. Anticipated project dates: Start date: 913/16 End date: 2/28/17 Will you construct during the wet season? X Yes ❑ No Page 110 2.1.6 Element 6: Protect Slopes All cut and fill slopes will be designed, constructed, and protected in a manner that minimizes erosion. The following specific BMP(s) will be used to protect slopes for this project: Interceptor Dike and Swales if necessary. Alternate slope protection BMP(s) are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMP(s) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix D). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix D), the Certified Erosion and Sediment Control Lead will promptly initiate the implementation of one or more of the alternative BMP(s) listed in Appendix C after the first sign that existing BMP(s) are ineffective or failing. Inspect diversion dikes and interceptor swales once a week and after every rainfall. Immediately remove sediment from the flow area. Damage caused by construction traffic or other activity must be repaired before the end of each working day. Check outlets and make timely repairs as needed to avoid gully formation. When the area below the temporary diversion dike is permanently stabilized, remove the dike and fill and stabilize the channel to blend with the natural surface. Will steep slopes be present at the site during construction? ❑ Yes X No Page 111 2.1.7 Element 7: Protect Drain Inlets All storm drain inlets and culverts made operable during construction shall be protected to prevent unfiltered or untreated water from entering the drainage conveyance system. However, the first priority is to keep all access roads clean of sediment and keep street wash water separate from entering storm drain inlets until treatment can be provided. Storm Drain Inlet Protection will be implemented for all drainage inlets and culverts that could potentially be impacted by sediment -laden runoff on and near the project site. If the BMP options listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix D), or if no BMPs are listed above but deemed necessary during construction, the Certified Erosion and Sediment Control Lead Shall implement one or more of the alternative BMP inlet protection options listed in Appendix C. Inspect and repair as needed. Add rock as needed to maintain the intended function. Clean energy dissipater if sediment builds up. Page 112 2.1.8 Element 8: Stabilize Channels and Outlets Where site runoff is to be conveyed in channels, or discharged to a stream or some other natural drainage point, efforts will be taken to prevent downstream erosion. It is not likely that runoff will be directed to channels or outlets as part of this construction project. Therefore, no specific BMPs for channel and outlet stabilization are proposed. Alternate channel and outlet stabilization BMPs are included in Appendix C as a quick reference tool for the onsite inspector in the event the BMPs) listed above are deemed ineffective or inappropriate during construction to satisfy the requirements set forth in the General NPDES Permit (Appendix D). To avoid potential erosion and sediment control issues that may cause a violation(s) of the NPDES Construction Stormwater permit (as provided in Appendix D), the Certified Erosion and Sediment Control Lead will promptly initiate the implementation of one or more of the alternative BMPs listed in Appendix C after the first sign that existing BMPs are ineffective or failing. Provide stabilization, including armoring material, adequate to prevent erosion of outlets, adjacent stream banks, slopes, and downstream reaches, will be installed at the outlets of all conveyance systems. Page 113 2.1.9 Element 9: Control Pollutants The following pollutants are anticipated to be present on -site: Table 2 — Pollutants _ Pollutant (List pollutants and source, if applicable) Construction Waste Materials Concrete Waste All pollutants, including waste materials and demolition debris, that occur onsite shall be handled and disposed of in a manner that does not cause contamination of stormwater. Good Stormwater Pollution Prevention Plan 9 housekeeping and preventative measures will be taken to ensure that the site will be kept clean, well -organized, and free of debris. If required, BMPs tc be implemented to control specific sources of pollutants are discussed below. Concrete handling. The facility does not require a Spill Prevention, Control, and Countermeasure (SPCC) plan under the Federal regulations of the Clean Water Act (CWA). Will maintenance, fueling, and/or repair of heavy equipment and vehicles occur on -site? ❑ Yes X No Will wheel wash or tire bath system BMPs be used during construction? ❑ Yes X No Will pH -modifying sources be present on -site? ❑ Yes X No Table 3 — pH -Modifying Sources ❑ I None Bulk cement Cement kiln dust ❑ ❑ ❑ Fly ash ❑ Other cementitious materials ❑ New concrete washing or curing waters ❑ Waste streams generated from concrete grinding and sawing ❑ Exposed aggregate processes ❑ Dewatering concrete vaults ❑ Concrete pumping and mixer washout waters Recycled concrete ❑ Recycled concrete stockpiles ❑ Other (i.e., calcium lignosulfate) [please describe: ] Page 1 14 Concrete trucks must not be washed out onto the ground, or into storm drains, open ditches, streets, or streams. Excess concrete must not be dumped on -site, except in designated concrete washout areas with appropriate BMPs installed. Will uncontaminated water from water -only based shaft drilling for construction of building, road, and bridge foundations be infiltrated provided the wastewater is managed in a way that prohibits discharge to surface waters? ❑ Yes X No Page 115 2.1.10 Element 10: Control Dewatering Dewatering is not expected during construction activities however could be a possibility during peak groundwater conditions during trenching for deeper utilities and/or foundations. It is not anticipated that this groundwater will be contaminated and therefore will be directed to sediment ponds. Table 4 — Dewatering BMPs X I Infiltration ❑ Transport off -site in a vehicle (vacuum truck for legal disposal) ❑ Ecology -approved on -site chemical treatment or other suitable treatment technologies ❑ Sanitary or combined sewer discharge with local sewer district approval (last resort) ❑ Use of sedimentation bag with discharge to ditch or swale (small volumes of localized Page 116 2.1.11 Element 11: Maintain BMPs All temporary and permanent Erosion and Sediment Control (ESC) BMPs shall be maintained and repaired as needed to ensure continued performance of their intended function. Maintenance and repair shall be conducted in accordance with each particular BMP specification (see Volume 11 of the SWMMWW or Chapter 7 of the SWMMEW). Visual monitoring of all BMPs installed at the site will be conducted at least once every calendar week and within 24 hours of any stormwater or non-stormwater discharge from the site. If the site becomes inactive and is temporarily stabilized, the inspection frequency may be reduced to once every calendar month. All temporary ESC BMPs shall be removed within 30 days after final site stabilization is achieved or after the temporary BMPs are no longer needed. Trapped sediment shall be stabilized on -site or removed. Disturbed soil resulting from removal of either BMPs or vegetation shall be permanently stabilized. Additionally, protection must be provided for all BMPs installed for the permanent control of stormwater from sediment and compaction. BMPs that are to remain in place following completion of construction shall be examined and restored to full operating condition. If sediment enters these BMPs during construction, the sediment shall be removed and the facility shall be returned to conditions specified in the construction documents. Page 117 2.1.12 Element 12: Manage the Project The project will be managed based on the following principles: Projects will be phased to the maximum extent practicable and seasonal work limitations will be taken into account. Inspection and monitoring: o Inspection, maintenance and repair of all BMPs will occur as needed to ensure performance of their intended function. o Site inspections and monitoring will be conducted in accordance with Special Condition S4 of the CSWGP. Sampling locations are indicated on the Site Map. Sampling station(s) are located in accordance with applicable requirements of the CSWGP. Maintain an updated SWPPP. o The SWPPP will be updated, maintained, and implemented in accordance with Special Conditions S3, S4, and S9 of the CSWGP. As site work progresses the SWPPP will be modified routinely to reflect changing site conditions. The SWPPP will be reviewed monthly to ensure the content is current. Table 5 — Management X Design the project to fit the existing topography, soils, and drainage patterns X Emphasize erosion control rather than sediment control X Minimize the extent and duration of the area exposed X Keep runoff velocities low X Retain sediment on -site X X Thoroughly monitor site and maintain all ESC measures Schedule major earthwork during the dry season Other (please describe) Page 118 Optional: Fill out Table 6 by listing the BMP associated with specific_ construction QGti ies. Identify the phase of the project {if applicable}, To increase awareness of seasonal requirements, indicate if the activity falls within t}ie wet or dry season. Table 6 — BMP Implementation Schedule Page 119 Page 120 2.1.13 Element 13: Protect Low Impact Development (LID) BMPs No Low Impact Development BMPs are proposed for this project and as such there are no protection measures to implement. Page 121 3 Pollution Prevention Team Table 7 — Team Information Title Names Phone Number TBD TBD Certified Erosion and Sediment Control Lead (CESCL) Resident Engineer Sean Mallon 206.522.9510 Emergency Ecology Contact Howard Zorzi 425.649.7130 _ Emergency Permittee/ Jeff Parker 425.270.9782 Owner Contact Non -Emergency Owner Contact Monitoring Personnel TBD TBD Ecology Regional Office Northwest Region 425.649.7000 Page 122 4 Monitoring and Sampling Requirements Monitoring includes visual inspection, sampling for water quality parameters of concern, and documentation of the inspection and sampling findings in a site log book. A site log book will be maintained for all on -site construction activities and will include: • A record of the implementation of the SWPPP and other permit requirements Site inspections Stormwater sampling data A blank inspection form can be found under Appendix D. The site log book must be maintained on -site within reasonable access to the site and be made available upon request to Ecology or the local jurisdiction. Numeric effluent limits may be required for certain discharges to 303(d) listed waterbodies. See CSWGP Special Condition S8 and Section 5 of this template. 4.1 Site Inspection Site inspections will be conducted at least once every calendar week and within 24 hours following any discharge from the site. For sites that are temporarily stabilized and inactive, the required frequency is reduced to once per calendar month. The discharge point(s) are indicated on the Site Map (see Appendix A) and in accordance with the applicable requirements of the CSWGP. 4.2 Stormwater Quality Sampling Stormwater should remain on site however if a discharge occurs, quality sampling shall take place as follows: 4.2.1 Turbidity Sampling Requirements include calibrated turbidity meter or transparency tube to sample site discharges for compliance with the CSWGP. Sampling will be conducted at all discharge points at least once per calendar week. Method for sampling turbidity: Table 8 — Turbidity Samplinq Method ❑ Turbidity Meter/Turbid i meter (required for disturbances 5 acres or greater in size) X I Transparency Tube (option for disturbances less than 1 acre and up to 5 acres in size) The benchmark for turbidity value is 25 nephelometric turbidity units (NTU) and a transparency less than 33 centimeters. If the discharge's turbidity is 26 to 249 NTU or the transparency is less than 33 cm but equal to or greater than 6 cm, the following steps will be conducted: Page 123 1. Review the SWPPP for compliance with Special Condition S9. Make appropriate revisions within 7 days of the date the discharge exceeded the benchmark. 2. Immediately begin the process to fully implement and maintain appropriate source control and/or treatment BMPs as soon as possible. Address the problems within 10 days of the date the discharge exceeded the benchmark. If installation of necessary treatment BMPs is not feasible within 10 days, Ecology may approve additional time when the Permittee requests an extension within the initial 10-day response period. 3. Document BMP implementation and maintenance in the site log book. If the turbidity exceeds 250 NTU or the transparency is 6 cm or less at any time, the following steps will be conducted: Telephone or submit an electronic report to the applicable Ecology Region's Environmental Report Tracking System (ERTS) within 24 hours. • Northwest Region (King, Kitsap, Island, San Juan, Skagit, Snohomish, Whatcom): (425) 649-7000 or httri://www.ecy.wa,gov/programs/spills/forris/nerts online/NWRO nerts online.html 2. Immediately begin the process to fully implement and maintain appropriate source control and/or treatment BMPs as soon as possible. Address the problems within 10 days of the date the discharge exceeded the benchmark. If installation of necessary treatment BMPs is not feasible within 10 days, Ecology may approve additional time when the Permittee requests an extension within the initial 10-day response period 3. Document BMP implementation and maintenance in the site log book. 4. Continue to sample discharges daily until one of the following is true: Turbidity is 25 NTU (or lower). ■ Transparency is 33 cm (or greater). • Compliance with the water quality limit for turbidity is achieved. 0 1 - 5 NTU over background turbidity, if background is less than 50 NTU 0 1 % - 10% over background turbidity, if background is 50 NTU or greater The discharge stops or is eliminated. Page 124 4.2.2 pH Sampling pH monitoring is required for "Significant concrete work" (i.e., greater than 1000 cubic yards poured concrete over the life of the project). The use of recycled concrete or engineered soils (soil amendments including but not limited to Portland cement -treated base [CTB], cement kiln dust [CKD] or fly ash) also requires pH monitoring. For significant concrete work, pH sampling will start the first day concrete is poured and continue until it is cured, typically three (3) weeks after the last pour. For engineered soils and recycled concrete, pH sampling begins when engineered soils or recycled concrete are first exposed to precipitation and continues until the area is fully stabilized. If the measured pH is 8.5 or greater, the following measures will be taken: 1. Prevent high pH water from entering storm sewer systems or surface water. 2. Adjust or neutralize the high pH water to the range of 6.5 to 8.5 su using appropriate technology such as carbon dioxide (CO2) sparging (liquid or dry ice). 3. Written approval will be obtained from Ecology prior to the use of chemical treatment other than CO2 sparging or dry ice. Method for sampling pH: Table 9 — pH Sampling Method ❑ pH meter X pH test kit ❑ Wide range pH indicator paper Page 125 5 Discharges to 303(d) or Total Maximum Daily Load (TMDL) Waterbodies 5.1 303(d) Listed Waterbodies Is the receiving water 303(d) (Category 5) listed for turbidity, fine sediment, phosphorus, or pH? ❑ Yes XNo List the impairment(s): N/A 5.2 TMDL Waterbodies Waste Load Allocation for CWSGP discharges: N/A List and describe BMPs: N/A Discharges to TMDL receiving waterbodies will meet in -stream water quality criteria at the point of discharge. The Construction Stormwater General Permit Proposed New Discharge to an Impaired Water Body form is included in Appendix F. Page 126 6 Reporting and Record Keeping 6.1 Record Keeping 6.1.1 Site Log Book A site log book will be maintained for all on -site construction activities and will include: A record of the implementation of the SWPPP and other permit requirements • Site inspections Sample logs 6.1.2 Records Retention Records will be retained during the life of the project and for a minimum of three (3) years following the termination of permit coverage in accordance with Special Condition S5.0 of the CSWGP. Permit documentation to be retained on -site: • CSWGP ■ Permit Coverage Letter • SWPPP • Site Log Book Permit documentation will be provided within 14 days of receipt of a written request from Ecology. A copy of the SWPPP or access to the SWPPP will be provided to the public when requested in writing in accordance with Special Condition S5.G.2.b of the CSWGP. 6.1.3 Updating the SWPPP The SWPPP will be modified if: Found ineffective in eliminating or significantly minimizing pollutants in stormwater discharges from the site. There is a change in design, construction, operation, or maintenance at the construction site that has, or could have, a significant effect on the discharge of pollutants to waters of the State. The SWPPP will be modified within seven (7) days if inspection(s) or investigation(s) determine additional or modified BMPs are necessary for compliance. An updated timeline for BMP implementation will be prepared. Page 127 6.2 Reporting 6.2.1 Discharge Monitoring Reports Cumulative soil disturbance is one (1) acre or larger; therefore, Discharge Monitoring Reports (DMRs) will be submitted to Ecology monthly. If there was no discharge during a given monitoring period the DMR will be submitted as required, reporting "No Discharge". The DMR due date is fifteen (15) days following the end of each calendar month. DMRs will be reported online through Ecology's WQWebDMR System. 6.2.2 Notification of Noncompliance If any of the terms and conditions of the permit is not met, and the resulting noncompliance may cause a threat to human health or the environment, the following actions will be taken: 1. Ecology will be notified within 24-hours of the failure to comply by calling the applicable Regional office ERTS phone number (Regional office numbers listed below). 2. Immediate action will be taken to prevent the discharge/pollution or otherwise stop or correct the noncompliance. If applicable, sampling and analysis of any noncompliance will be repeated immediately and the results submitted to Ecology within five (5) days of becoming aware of the violation. 3. A detailed written report describing the noncompliance will be submitted to Ecology within five (5) days, unless requested earlier by Ecology. Anytime turbidity sampling indicates turbidity is 250 NTUs or greater, or water transparency is 6 cm or less, the Ecology Regional office will be notified by phone within 24 hours of analysis as required by Special Condition S5.A of the CSWGP. • Southwest Region at (360) 407-6300 for Clallam, Clark, Cowlitz, Grays Harbor, Jefferson, Lewis, Mason, Pacific, Pierce, Skamania, Thurston, or Wahkiakum Include the following information: 1. Your name and / Phone number 2. Permit number 3. City / County of project 4. Sample results 5. Date / Time of call 6. Date / Time of sample 7. Project name In accordance with Special Condition S4.D.5.b of the CSWGP, the Ecology Regional office will be notified if chemical treatment other than COz sparging is planned for adjustment of high pH water. Page 128 Appendix/Glossary A. Site Map Page 129 Is, a �;•k�^x5:, �,v. F�,�"ds=Sas"arx ;'>r: '=ss�-. �:�4Q� J Y,b�,o .^5., �^} = eGsNd ;.3N ��_ 3o•�q yri "g'�„yo 6} � �� iS�g H�e''�I'Cz`C �: i�Q�� '. y 2'G ��5 i`=•t'��'+y� ,. ��R=� 'Srn5 y��'<�"e 's�o �• '��._ �q�3yfi�a= =g��or ^.,'-�� Or:�F�'�" ca`n��oXT.v-,C6�V0➢? __,:. •�=pz�;�.; 21m2 ��'�Y3�E9q`'o^ "�`G __Q�Rco_�4 ¢E'eYS �•J- - :3 :=FzmFw - �_ _� a-3I •z ,.��'?-��Q�^�_ - � his Rs.^- 4 �.��Y Adz! -�'' � np wG .o XI �ai=� - �.Y g� ^�- ~� Lea ^•�G� ^ .,3 9 F• N 5 ,�� Fx ;;;,rr- ��a `rasa `• _� �H' PACIFIC HIGHWAY SOUTH - SR-M wac rnra�wAn � I I � � ` C' i 9n c :IL J1�• it gq} E. �8g - �IIim O� 50 On rm zm 00 im c r D { m 0 O z O O n co m� A �m n0 :< rn nz O-0 cr A m S z 1 O z Page 130 - n � Y Ee rn m La 0 Z 0 0 r 0 N 0 `r'- oat• •_ R m \F £g P 4 8� a� 2p rn -4 10 m >m = 1 gr..£n Page 131 B. BMP Detail BMP C101: Preserving Natural Vegetation BMP C103: High Visibility Fence BMP C105: Stabilized Construction Entrance/Exit BMP C120: Temporary and Permanent Seeding BMP C140: Dust Control BMP C151: Concrete Handling BMP C200: Interceptor Dike and Swale BMP C220: Storm Drain Inlet Protection BMP C233: Silt Fence BMP C241: Temporary Sediment Pond Page 132 C. Correspondence N/A Page 133 D. Site Inspection Form Construction Stormwater Site Inspection Form Project Name Permit # Inspection Date Time Name of Certified Erosion Sediment Control Lead (CESCL) or qualified inspector if less than one acre Print Name: Approximate rainfall amount since the last inspection (in inches): Approximate rainfall amount in the last 24 hours (in inches): Current Weather Clear Cloudy Mist Rain Wind ❑ Fog A. Type of inspection: Weekly Post Storm Event ❑ Other B. Phase of Active Construction (check all that apply): Pre Construction/installation of erosion/sediment Clearing/Demo/Grading Infrastructure/storm/roads controls Concrete pours Vertical Utilities Construction/buildings Offsite improvements Site temporary stabilized Final stabilization C. Questions: 1. Were all areas of construction and discharge points inspected? Yes No 2. Did you observe the presence of suspended sediment, turbidity, discoloration, or oil sheen Yes _ No 3. Was a water quality sample taken during inspection? (refer to permit conditions S4 & 55) Yes _ No _ 4. Was there a turbid discharge 250 NTU or greater, or Transparency 6 cm or less?* Yes _ No 5. If yes to #4 was it reported to Ecology? Yes _ No 6. Is pH sampling required? pH range required is 6.5 to 8.5. Yes _ No If answering yes to a discharge, describe the event. Include when, where, and why it happened; what action was taken, and when. *If answering yes to # 4 record NTU/Transparency with continual sampling daily until turbidity is 25 NTU or less/ transparency is 33 cm or greater. Sampling Results: Date: Parameter I Method (circle one) Result other/Note NTU cm pH Turbidity tube, meter, laboratory pH Paper, kit, meter Page 1 Page 134 Construction Stormwater Site Inspection Form D. Check the observed status of all items. Provide "Action Required "details and dates. Element # Inspection BMPs Inspected BMP needs maintenance BMP failed Action required (describe in section F) yes no n/a 1 Before beginning land disturbing Clearing activities are all clearing limits, Limits natural resource areas (streams, wetlands, buffers, trees) protected with barriers or similar BMPs? (high visibility recommended) 2 Construction access is stabilized Construction with quarry spalls or equivalent Access BMP to prevent sediment from being tracked onto roads? Sediment tracked onto the road way was cleaned thoroughly at the end of the day or more frequent as necessary. 3 Are flow control measures installed Control Flow to control stormwater volumes and Rates velocity during construction and do they protect downstream properties and waterways from erosion? If permanent infiltration ponds are used for flow control during construction, are they protected from siltation? 4 All perimeter sediment controls Sediment (e.g. silt fence, wattles, compost Controls socks, berms, etc.) installed, and maintained in accordance with the Stormwater Pollution Prevention Plan (SWPPP). Sediment control BMPs (sediment ponds, traps, filters etc.) have been constructed and functional as the first step of grading. Stormwater runoff from disturbed areas is directed to sediment removal BMP. 5 Have exposed un-worked soils Stabilize been stabilized with effective BMP Soils to prevent erosion and sediment deposition? Page 2 Page 135 Construction Stormwater Site Inspection Form Element # Inspection BMPs BMP needs BMP Action Inspected maintenance failed required (describe in yes no n/a section F) 5 Are stockpiles stabilized from erosion, Stabilize Soils protected with sediment trapping Cont. measures and located away from drain inlet, waterways, and drainage channels? Have soils been stabilized at the end of the shift, before a holiday or weekend if needed based on the weather forecast? Has stormwater and ground water 6 been diverted away from slopes and Protect disturbed areas with interceptor dikes, Slopes pipes and or swales? Is off -site storm water managed separately from stormwater generated on the site? Is excavated material placed on uphill side of trenches consistent with safety andspa e considerations? Have check dams been placed at regular intervals within constructed channels that are cut down a slope? 7 Storm drain inlets made operable Drain Inlets during construction are protected. Are existing storm drains within the influence of the projectprotected? 8 Have all on -site conveyance channels Stabilize been designed, constructed and Channel and stabilized to prevent erosion from Outlets expected peak flows? Is stabilization, including armoring material, adequate to prevent erosion of outlets, adjacent stream banks, slopes and downstream conveyance systems? 9 Are waste materials and demolition Control debris handled and disposed of to Pollutants prevent contamination of stormwater? Has cover been provided for all chemicals, liquid products, petroleum products, and other material? Has secondary containment been provided capable of containing 110% of the volume? Were contaminated surfaces cleaned immedlately after a s ill incident? Were BMPs used to prevent contamination of stormwater by a pH modifving sources? Page 3 Page 136 Construction Stormwater Site Inspection Form Element # Inspection BMPs BMP needs BMP Action Inspected maintenance failed required (describe in yes no n/a section F) 9 Wheel wash wastewater is handled Cont. and disposed of properly. 10 Concrete washout in designated areas. Control No washout or excess concrete on the Dewatering ground. Dewatering has been done to an approved source and in compliance with the SWPPP. Were there any clean non turbid dewatering discharges? 11 Are all temporary and permanent Maintain erosion and sediment control BMPs BMP maintained to perform as intended? 12 Has the project been phased to the Manage the maximum degree practicable? Project Has regular inspection, monitoring and maintenance been performed as required by the permit? Has the SWPPP been updated, implemented and records maintained? 13 Is all Bioretention and Rain Garden Protect LID Facilities protected from sedimentation with appropriate BMPs? Is the Bioretention and Rain Garden protected against over compaction of construction equipment and foot traffic to retain its infiltration capabilities? Permeable pavements are clean and i free of sediment and sediment laden• water runoff. Muddy construction equipment has not been on the base material or pavement. Have soiled permeable pavements been cleaned of sediments and pass infiltration test as required by stormwater manual methodology? Heavy equipment has been kept off existing soils under LID facilities to retain infiltration rate. E. Check all areas that have been inspected. ✓ All in place BMPs All disturbed soils [] All concrete wash out area 7 All material storage areas C All discharge locations ❑ All equipment storage areas All construction entrances/exits Page 4 Page 137 Construction Stormwater Site Inspection Form F. Elements checked "Action Required" (section D) describe corrective action to be taken. List the element number; be specific on location and work needed. Document, initial, and date when the corrective action has been completed _a_J Element # Description and Location Action Required Completion Date_ initials Attach additional page if needed 5i gn the foIIowin certification: "I certify that this report is true, accurate, and complete, to the best of my knowledge and belief" Inspected by: (print) Title/Qualification of Inspector: (Signature) Date: Page 5 Page 138 E. Construction Stormwater General Permit (CSWGP) Page 139 Issuance Date: November 18, 2015 Effective Date: January 1, 2016 Expiration Date: December 31, 2020 CONSTRUCTION STORMWATER GENERAL PERMIT National Pollutant Discharge Elimination System (NPDES) and State Waste Discharge General Permit for Stormwater Discharges Associated with Construction Activity State of Washington Department of Ecology Olympia, Washington 98504 In compliance with the provisions of Chapter 90.48 Revised Code of Washington (State of Washington Water Pollution Control Act) and Title 33 United States Code, Section 1251 et seq. The Federal Water Pollution Control Act (The Clean Water Act) L3irtil this permit expires, is modified, or revoked, Permittees that have properly obtained coverage under this general permit arc authorized to discharge in accordance With the Special and general conditions that follow. *Hc,. Bartlett Water Quality Program Manager Washington State Department of Ecology Page 140 TABLE OF CONTENTS LISTOF TABLES...........................................................................................................................3 SUMMARY OF PERMIT REPORT SUBMITTALS.....................................................................4 SPECIALCONDITIONS................................................................................................................5 S1. PERMIT COVERAGE........................................................................................................5 S2. APPLICATION REQUIREMENTS...................................................................................8 S3. COMPLIANCE WITH STANDARDS.............................................................................12 S4. MONITORING REQUIREMENTS, BENCHMARKS, AND REPORTINGTRIGGERS.........................................._...._..................:.............................13 S5. REPORTING AND RECORDKEEPING REQUIREMENTS.........................................20 S6. PERMIT FEES...................................................................................................................23 ST SOLID AND LIQUID WASTE DISPOSAL....................................................................23 S8. DISCHARGES TO 303(d) OR TMDL WATERBODIES................................................23 S9. STORMWATER POLLUTION PREVENTION PLAN...................................................27 S10. NOTICE OFTERMINATION.........................................................................................37 GENERALCONDITIONS...........................................................................................................38 G1. DISCHARGE VIOLATIONS...........................................................................................38 G2. SIGNATORY REQUIREMENTS.....................................................................................38 G3. RIGHT OF INSPECTION AND ENTRY..........................._.......,.....................................39 G4. GENERAL PERMIT MODIFICATION AND REVOCATION ......................................39 G5. REVOCATION OF COVERAGE UNDER THE PERMIT ......................................... .... 39 G6. REPORTING A CAUSE FOR MODIFICATION............................................................40 G7. COMPLIANCE WITH OTHER LAWS AND STATUTES...... ..................................... ;.40 G8. DUTY TO REAPPLY.......................................................................................................40 G9. TRANSFER OF GENERAL PERMIT COVERAGE.......................................................41 G10. REMOVED SUBSTANCES.............................................................................................41 GIL DUTY TO PROVIDE INFORMATION...........................................................................41 G 12. OTHER REQUIREMENTS OF 40 CFR...........................................................................41 G13. ADDITIONAL MONITORING........................................................................................41 G 14. PENALTIES FOR VIOLATING PERMIT CONDITIONS .......... :.................................. 41 G15. UPSET...............................................................................................................................42 G16. PROPERTY RIGHTS........................................................................................................42 Con.clrnclion S7ornnivrer General Permit Pages 2 Page 141 G17. DUTY TO COMPLY........................................................................................................42 G18. TOXIC POLLUTANTS.....................................................................................................42 G19. PENALTIES FOR TAMPERING.....................................................................................43 G20. REPORTING PLANNED CHANGES .............................................. ....................... ._.... 43 G21. REPORTING OTHER INFORMATION..........................................................................43 G22. REPORTING ANTICIPATED NON-COMPLIANCE.....................................................43 G23. REQUESTS TO BE EXCLUDED FROM COVERAGE UNDER THE PERMIT .......... 44 G24. APPEALS..........................................................................................................................44 G25. SEVERABILITY...............................................................................................................44 G26. BYPASS PROHIBITED....................................................................................................44 APPENDIXA — DEFINITIONS...................................................................................................47 APPENDIXB — ACRONYMS.....................................................................................................55 LIST OF TABLES Table 1: Summary of Required Submittals................................................................................... 4 Table 2: Summary of Required On -site Documentation............................................................... 4 Table 3: Summary of Primary Monitoring Requirements.......................................................... 15 Table 4: Monitoring and Reporting Requirements..................................................................... 17 Table 5: Turbidity, Fine Sediment & Phosphorus Sampling and Limits for 303(d)-Listed Waters.................................................................................................... 25 Table 6: pH Sampling and Limits for 303(d)-Listed Waters ...................................................... 26 Corrslruriion Stoop rarer General Permil Page 3 Page 142 SUMMARY OF PERMIT REPORT SUBMITTALS Refer to the Special and General Conditions within this permit for additional submittal requirements. Appendix A provides a list of definitions. Appendix B provides a list of acronyms. Table 1: Summary of Required Submittals Permit ` Submittal Frequency First Submittal Date Section S5.A and High Turbid itylTransparency Phone As Necessary Within 24 hours S8 Reporting S53 Discharge Monitoring Report Monthly` Within 15 days following the end of each month S5.F and Noncompliance Notification — As necessary Within 24-hours S8 Telephone Notification As necessary i Within 5 Days of non - S55 Noncompliance Notification — Written Report compliance S9.0 Request for Chemical Treatment As necessary Written approval from Form Ecology is required prior to using chemical treatment (with the exception of dry ice or COz to adjust pH) G2 Notice of Change in Authorization As necessary G6 Permit Application for Substantive As necessary Changes to the Discharge G8 Application for Permit Renewal 1/permit cycle No later than 180 days before expiration G9 Notice of Permit Transfer As necessary i Notice of Planned Changes As necessary G22 Anticipated Non- As necessary jReporting compliance SPECIAL NOTE: *Pcrmittces must submit electronic Discharge Monitoring Reports (DMRs) to the Washington State Department of Ecology monthly, regardless of site discharge, for the full duration of pemvt coverage. Refer to Section S5.13 of this General Permit for more specific information regarding DMRs. Table 2: Summary of Required On -site Documentation Document Title Permit Conditions Permit Coverage Letter See Conditions S2, S5 Construction Stormwater General Permit See Conditions 12, S5 Site Log Book See Conditions S4, S5 Stormwater pollution Prevention Plan (SW PPP) See Conditions S9, S5 Coagwricuo n iormwulrr General 1'eruril P tc ._I Page 143 SPECIAL CONDITIONS S1. PERMIT COVERAGE A. Permit Area This Constriction Stormwater General Permit (CSWGP) covers all areas of Washington State, except for federal operators and Indian Country as specified in Special Condition S 1.E.3. B. Operators Required to Seek Coverage Under this General Permit: l . Operators of the following construction activities are required to seek coverage under this CSWGP: a. Clearing, grading and/or excavation that results in the disturbance of one or more acres (including off -site disturbance acreage authorized in S1.C.2) and discharges stormwater to surface waters of the State; and clearing, grading and/or excavation on sites smaller than one acre that are part of a larger common plan of development or sale, if the common plan of development or sale will ultimately disturb one acre or more and discharge stormwater to surface waters of the State. i. This includes forest practices (including, but not limited to, class IV conversions) that are part of a construction activity that will result in the disturbance of one or more acres, and discharge to surface waters of the State (that is, forest practices that prepare a site for construction activities); and b. Any size construction activity discharging stormwater to waters of the State that the Washington State Department of Ecology (Ecology): i. Determines to be a significant contributor of pollutants to waters of the State of Washington. ii. Reasonably expects to cause a violation of any water quality standard. 2. Operators of the following activities are not required to seek coverage under this CSWGP (unless specifically required under Special Condition S 1.13. Lb, above): a. Construction activities that discharge all stormwater and non-stormwater to ground water, sanitary sewer, or combined sewer, and have no point source discharge to either surface water or a storm sewer system that drains to surface waters of the State. b. Construction activities covered under an Erosivity Waiver (Special Condition S2.C). c. Routine maintenance that is performed to maintain the original line and grade, hydraulic capacity, or original purpose of a facility. Ct),7str11i11oJ1 S(orlmrater General Perini( Page , Page 144 C. Authorized Discharges: 1. Stormwater Associated with Construction Activity. Subject to compliance with the terms and conditions of this permit, Pennittees are authorized to discharge Stormwater associated with construction activity to surface waters of the State or to a storm sewer system that drains to surface waters of the State. (Note that "surface waters of the State" may exist on a construction site as well as off site; for example, a creek running through a site.) 2. Stormwater Associated with Construction Support Activity. This permit also authorizes stormwater discharge from support activities related to the permitted construction site (for example, an on -site portable rock crusher, off -site equipment staging yards, material storage areas, borrow areas, etc.) provided: a. The support activity relates directly to the permitted construction site that is required to have an NPDES permit; and b. The support activity is not a commercial operation serving multiple unrelated construction projects, and does not operate beyond the completion of the construction activity; and c. Appropriate controls and measures are identified in the Stormwater Pollution Prevention Plan (SWPPP) for the discharges from the support activity areas. 3. Non-Srormwater Discharge.+. The categories and sources of non-stormwater discharges identified below are authorized conditionally, provided the discharge is consistent with the terms and conditions of this permit: a. Discharges from fire -fighting activities. b. Fire hydrant system flushing. c. Potable water, including uncontaminated water line flushing. d. Hydrostatic test water. e. Uncontaminated air conditioning or compressor condensate. f. Uncontaminated ground water or spring water. g. Uncontaminated excavation dewatering water (in accordance with S9.D.10). h. Uncontaminated discharges from foundation or footing drains. i. Uncontaminated water used to control dust. Permittees must minimize the amount of dust control water used. j. Routine external building wash down that does not use detergents. k. Landscape irrigation water. The SWPPP must adequately address all authorized non-stormwater discharges, except for discharges from tire -fighting activities, and must comply with Special Condition S3. Constna•tion Stornnrutcr General PernO Page 6 Page 145 At a minimum, discharges from potable water (including water line flushing), fire hydrant system flushing, and pipeline hydrostatic test water must undergo the following: dechlorination to a concentration of 0.1 parts per million (ppm) or less, and pH adjustment to within 6.5 — 8.5 standard units (su), if necessary. D. Prohibited Discharges: The following discharges to waters of the State, including ground water, are prohibited. 1. Concrete wastewater. 2. Wastewater from washout and clean-up of stucco, paint, form release oils, curing compounds and other construction materials. 3. Process wastewater as defined by 40 Code of Federal Regulations (CFR) 122.2 (see Appendix A of this permit). 4. Slurry materials and waste from shaft drilling, including process wastewater from shaft drilling for construction of building, road, and bridge foundations unless managed according to Special Condition S9.D.9 j. 5. Fuels, oils, or other pollutants used in vehicle and equipment operation and maintenance. 6. Soaps or solvents used in vehicle and equipment washing. 7. Wheel wash wastewater, unless managed according to Special Condition S9.D.9. 8. Discharges from dewatering activities, including discharges from dewatering of trenches and excavations, unless managed according to Special Condition S9.D.10. E. Limits on Coverage Ecology may require any discharger to apply for and obtain coverage under an individual permit or another more specific general permit. Such alternative coverage will be required when Ecology determines that this CSWGP does not provide adequate assurance that water quality will be protected, or there is a reasonable potential for the project to cause or contribute to a violation of water quality standards. The following stormwater discharges are not covered by this permit: l . Post -construction stormwater discharges that originate from the site after completion of construction activities and the site has undergone final stabilization. 2. Non -point source silvicultural activities such as nursery operations, site preparation, reforestation and subsequent cultural treatment, thinning, prescribed burning, pest and tiro control. harvesting operations, surface drainage, or road construction and maintenance, from which there is natural runoff as excluded in 40 CFR Subpart 122. 3. Stormwater from any federal operator. C'onslruction Siornnrute r General Pernii! Pa,_ e 7 Page 146 4. Stormwater from facilities located on "Indian Country" as defined in 18 U.S.C.§ 1151, except portions of the Puyallup Reservation as noted below. Indian Country includes: a. All land within any Indian Reservation notwithstanding the issuance of any patent, and, including rights -of -way running through the reservation. This includes all federal, tribal, and Indian and non -Indian privately owned land within the reservation. b. All off -reservation Indian allotments, the Indian titles to which have not been extinguished, including rights -of -way running through the same. c. All off -reservation federal trust lands held for Native American Tribes. Puyallup Exception: Following the Puyallup Tribes of Indians Land Settlement Act of 1989, 25 U.S.C. § 1773; the permit does apply to land within the Puyallup Reservation except for discharges to surface water on land held in trust by the federal government. 5. Stormwater from any site covered under an existing NPDES individual permit in which stormwater management and/or treatment requirements are included for all stormwater discharges associated with construction activity. 6. Stormwater from a site where an applicable Total Maximum Daily Load (TMDL) requirement specifically precludes or prohibits discharges from construction activity, S2. APPLICATION REQUIREMENTS A. Permit Application Forms 1. Notice of Intent Form/Timeline a. Operators of new or previously unpermitted construction activities must submit a complete and accurate permit application (Notice of Intent, or NOI) to Ecology. b. Operators must apply using the electronic application form (NOI) available on Ecology's website httn:,/w%vw.ecy.wa.govleoerams'wq/stormwaterl constriction/index hrml. Permittees unable to submit electronically (for example, those who do not have an internet connection) must contact Ecology to request a waiver and obtain instructions on how to obtain a paper NOT. Department of Ecology Water Quality Program - Construction Stormwater PO Box 47696 Olympia, Washington 98504-7696 Construction Siornnrwer General Permit Page S Page 147 c. The operator must submit the NOI at least 60 days before discharging stormwater from construction activities and must submit it on or before the date of the first public notice (see Special Condition S2.13 below for details). The 30- day public comment period begins on the publication date of the second public notice. Unless Ecology responds to the complete application in writing, based on public comments, or any other relevant factors, coverage under the general permit will automatically commence on the thirty-first day following receipt by Ecology of completed NOI, or the issuance date of this permit, whichever is later; unless Ecology specifies a later date in writing as required by WAC 173- 226-200(2). d. If an applicant intends to use a Best Management Practice (BMP) selected on the basis of Special Condition S9.C.4 ("demonstrably equivalent" BMPs), the applicant must notify Ecology of its selection as part of the NOI. In the event the applicant selects BMPs after submission of the NOI, it must provide notice of the selection of an equivalent BMP to Ecology at least 60 days before intended use of the equivalent BMP. e. Permittees must notify Ecology regarding any changes to the information provided on the NOI by submitting an updated NOI. Examples of such changes include, but are not limited to: i. Changes to the Permittee's mailing address, ii. Changes to the on -site contact person information, and iii. Changes to the area/acreage affected by construction activity. Applicants must notify Ecology if they are aware of contaminated soils and/or groundwater associated with the construction activity. Provide detailed inforration with the NOI (as known and readily available) on the nature and extent of the contamination (concentrations, locations, and depth), as well as pollution prevention and/or treatment BMPs proposed to control the discharge of soil and/or groundwater contaminants in stormwater. Examples orsuch detail may include, but are not limited to: i. List or table of all known contaminants with laboratory test results showing concentration and depth, ii. Map with sample locations, iii. Temporary Erosion and Sediment Control (TESC) plans, iv. Related portions of the Stormwater Pollution Prevention Plan (SWPPP) that address the management of contaminated and potentially contaminated construction stormwater and dewatering water, V. Dewatering plan and/or dewatering contingency plan, C onsU'urrron Slurimrrrhr Gcucrul pormi( p:W,C ') Page 148 2. Transfer of Coverage Form The Permittee can transfer current coverage under this permit to one or more new operators, including operators of sites within a Common Plan of Development, provided the Permittee submits a Transfer of Coverage Form in accordance with General Condition G9. Transfers do not require public notice. B. Public Notice For new or previously unpennitted construction activities, the applicant must publish a public notice at least one time each week for two consecutive weeks, at ]east 7 days apart, in a newspaper with general circulation in the county where the construction is to take place. The notice must contain: l . A statement that "The applicant is seeking coverage under the Washington State Department of Ecology's Construction Stormwater NPDES and State Waste Discharge General Permit". 2. The name, address and location of the construction site. 3. The name and address of the applicant. 4. The type of construction activity that will result in a discharge (for example, residential construction, commercial construction, etc.), and the number of acres to be disturbed. 5. The name of the receiving water(s) (that is, the surface water(s) to which the site will discharge), or, if the discharge is through a storm sewer system, the name of the operator of the system. 6. The statement: "Any persons desiring to present their views to the Washington State Department of Ecology regarding this application, or interested in Ecology's action on this application, may notify Ecology in writing no later than 30 days of the last date of publication of this notice. Ecology reviews public comments and considers whether discharges from this project would cause a measurable change in receiving water quality, and. ifso. whether the project is necessary and in the overriding public interest according to Tier it antidegradat io n requirements under WAC 173-201 A-320. Comment_% can be submitted to: Department of Ecology, PO Box 47696, Olympia, Washington 98504-7696 Attn: Water Quality Program, Construction Stormwater." C'unswumon S7ornnrurer General Perniif Page 10 Page 149 C. Erosivity Waiver Construction site operators may qualify for an erosivity waiver from the CSWGP if the following conditions are met: 1. The site will result in the disturbance of fewer than 5 acres and the site is not a portion of a common plan of development or sale that will disturb 5 acres or greater. 2. Calculation of Erosivity "R" Factor and Regional Timeframe: a. The projcct's rainfall erosivity factor ("R" Factor) must be less than 5 during the period of construction activity, as calculated (see the CSWGP homepagc htt :Ilw%w.cc v.wa, ovi ro raTh'"dw lstoM)water/cantitntctionlindex.httni for a link to the EPA's calculator and step by step instructions on computing the "R" Factor in the EPA Erosivity Waiver Fact Sheet). The period of construction activity starts when the land is first disturbed and ends with final stabilization. In addition: b. The entire period of construction activity must fall within the following timeframes: i. For sites west of the Cascades Crest: June 15 — September 15. ii. For sites east of the Cascades Crest, excluding the Central Basin: June 15 — October 15. iii. For sites east of the Cascades Crest, within the Central Basin: no additional timeframe restrictions apply. The Central Basin is defined as the portions of Eastern Washington with mean annual precipitation of less than 12 inches. For a map of the Central Basin (Average Annual Precipitation Region 2). refer to htt:llwww.ecv.wa, ovI rn ramslw lstormwaterl construe tion+resources, idat't ance.htin l. 3. Constriction site operators must submit a complete Erosivity Waiver certification form at least one week berore disturbing the land. Certirication must include statements that the operator will: a. Comply with applicable local stormwater requirements; and b. Implement appropriate erosion and sediment control BMPs to prevent violations of water quality standards. 4. This waiver is not available for facilities declared significant contributors of poliutants as defined in Special Condition SI.B. Lb. or for any sim conshuction activity that could reasonably expect to cause a violation of any water quality standard as defined in Special Condition SI.B.Lb. ii. 5. This waiver does not apply to construction activities which include non- stonnwater discharges listed in Special Condition Sl.C.3. C onb'iractioit Storinwaier General Permit Page I I Page 150 6. If construction activity extends beyond the certified waiver period for any reason, the operator must either: a. Recalculate the rainfall erosivity "R" factor using the original start date and a new projected ending date and, if the "R" factor is still under 5 and the entire project falls within the applicable regional timeframe in Special Condition S2.C.2.b, complete and submit an amended waiver certification farm before the original waiver expires; or b. Submit a complete permit application to Ecology in accordance with Special Condition S2.A and B before the end of the certified waiver period. S3. COMPLIANCE WITH STANDARDS A. Discharges must not cause or contribute to a violation of surface water quality standards (Chapter 173-201A WAC), ground water quality standards (Chapter 173-200 WAC), sediment management standards (Chapter 173-204 WAC), and human health -based criteria in the National Toxics Rule (40 CFR Part 131.36). Discharges not in compliance with these standards are not authorized. B. Prior to the discharge of stormwater and non-stormwater to waters of the State, the Permittee must apply all known, available, and reasonable methods of prevention, control, and treatment (AKART). This includes the preparation and implementation of an adequate SWPPP, with all appropriate BMPs installed and maintained in accordance with the SWPPP and the terms and conditions of this permit. C. Ecology presumes that a Permittee complies with water quality standards unless discharge monitoring data or other site -specific information demonstrates that a discharge causes or contributes to a violation of water quality standards, when the Permittee complies with the following conditions. The Permittee must fully: l . Comply with all permit conditions, including planning, sampling, monitoring, reporting, and recordkeeping conditions. 2. Implement stormwater BMPs contained in stormwater management manuals published or approved by Ecology, or BMPs that are demonstrably equivalent to BMPs contained in stormwater technical manuals published or approved by Ecology, including the proper selection, implementation, and maintenance of all applicable and appropriate BMPs for on -site pollution control, (For purposes of this section, the stormwater manuals listed in Appendix 10 of the Phase I Municipal Stormwater Permit are approved by Ecology.) D. Where construction sites also discharge to ground water, the ground water discharges must also meet the terms and conditions of this CSWGP. Permittees who discharge to ground water through an injection well must also comply with any applicable requirements of the Underground Injection Control (UIC) regulations, Chapter 173-218 WAC. Construction Stornncarer General Pern+h Page 12 Page 151 S4. MONITORING REQUIREMENTS, BENCHMARKS, AND REPORTING TRIGGERS A. Site Log Book The Permittee must maintain a site log book that contains a record of the implementation of the SWPPP and other permit requirements, including the installation and maintenance of BMPs, site inspections, and stormwater monitoring. B. Site Inspections The Permittee's site inspections must include all areas disturbed by construction activities, all BMPs, and all stormwater discharge points under the Permittee's operational control. (See Special Conditions S4.13.3 and BA below for detailed requirements of the Permittee's Certified Erosion and Sediment Control Lead [CESCL].) Construction sites one acre or larger that discharge stormwater to surface waters of the State must have site inspections conducted by a certified CESCL. Sites less than one acre may have a person without CESCL certification conduct inspections. I. The Permittee must examine stormwater visually for the presence of suspended sediment, turbidity, discoloration, and oil sheen. The Permittee must evaluate the effectiveness of BMPs and determine if it is necessary to install, maintain, or repair BMPs to improve the quality of stormwater discharges. Based on the results of the inspection, the Permittee must correct the problems identified by: a. Reviewing the SWPPP for compliance with Special Condition S9 and making appropriate revisions within 7 days of the inspection. b. Immediately beginning the process of fully implementing and maintaining appropriate source control and/or treattent BMPs as soon as possible, addressing the problems no later than within 10 days of the inspection. If installation of necessary treatment BMPs is not feasible within 10 days, Ecology may approve additional time when an extension is requested by a Permittee within the initial 10-day response period. c. Documenting BMP implementation and maintenance in the site log book. 2. The Permittee must inspect all areas disturbed by construction activities, all BMPs, and all stormwater discharge points at least once every calendar week and within 24 hours of any discharge from the site. (For purposes of this condition, individual discharge events that last more than one day do not require daily inspections. For example, if a stormwater pond discharges continuously over the course of a week, only one inspection is required that wcek.) The Permittee may reduce the inspection frequency for temporarily stabilized, inactive sites to once every calendar month. COJUWnChO)I StormiruterGenerul Permit Page 13 Page 152 3. The Permittee must have staff knowledgeable in the principles and practices of erosion and sediment control. The CESCL (sites one acre or more) or inspector (sites less than one acre) must have the skills to assess the: a. Site conditions and construction activities that could impact the quality of stormwater, and b. Effectiveness of erosion and sediment control measures used to control the quality of stormwater discharges. 4. The SWPPP must identify the CESCL or inspector, who must be present on site or on -call at all times. The CESCL must obtain this certification through an approved erosion and sediment control training program that meets the minimum training standards established by Ecology (see BMP C 160 in the manual referred to in Special Condition S9.C.1 and 2). 5. The Permittee must summarize the results of each inspection in an inspection report or checklist and enter the report/checklist into, or attach it to, the site log book. At a minimum, each inspection report or checklist must include: a. Inspection date and time. b. Weather information, the general conditions during inspection and the approximate amount of precipitation since the last inspection, and precipitation within the last 24 hours. c. A summary or list of all implemented BMPs, including observations of all erosion/sediment control structures or practices. d. A description of the locations. i. Of BMPs inspected; ii. Of BMPs that need maintenance and why; iii. Of BMPs that failed to operate as designed or intended; and iv. Where additional or different BMPs are needed, and why, e. A description of stormwater discharged From the site. The Permittee must note the presence of suspended sediment, turbidity, discoloration, and oil sheen, as applicable. f. Any water quality monitoring performed during inspection. g. General comments and notes, including a brief description of any BMP repairs, maintenance or installations made following the inspection. h. A summary report and a schedule of implementation or the remedial actions that the Permittee plans to take i r the site inspection indicates that the site is out of compliance. The remedial actions taken must meet the requirements of the SWPPP and the permit. C onsiniction Srornnrwer General Pcrmil Pauc 14 Page 153 L The name, title, and signature of the person conducting the site inspection, a phone number or other reliable method to reach this person, and the following statement: "I certify that this report is true, accurate, and complete to the best of my knowledge and belief." Table 3: Summary of Primary Monitoring Requirements Size of Soil Weekly Site Weekly Weekly Weekly pH CESCL Disturbances Inspections Sampling w/ I Sampling wl Sampling2 Required for Turbidity Transparency Inspections? Mete Tube Sites that disturb Required Not Required Not Required Not Required No less than 1 acre, but are part of a larger Common Plan of Development Sites that disturb 1 Required Sampling Required — Required Yes acre or more, but either method' fewer than 5 acres Sites that disturb 5 Required Required Not Required Required Yes acres or more + Soil disturbance is calculated by adding together all areas that will be affected by construction activity. Construction activity means clearing, grading, excavation, and any other activity that disturbs the surface ofthe land, including ingress/egress from the site. t ircunstniction activity results in the disturbate of I acre or more, and invulves significant concrete work t I.0110 cubic yards ❑f poured over the life of a project) or the use of recycled concrete or cn€irivercd soils (soil amendments including but not limited to Portland cement -nested blse (C 81. cement kiln dust [CKD}, or fly ash). and atornrawcr fmm the aMcctcd area drains to surface waters of the State a to a storm sewer stormwatcr collection system that drains to other surface waters of the State, the Permince must conduct pH sampling in accordance with Special Condition S4.D. Sitcs with one or more acres, but fewer than 5 acres of soil disturbance, must conduct turbidity or transparency sampling in accordance with Special Condition S4.C. ' Sites equal to or.greatcr than 5 acres vfsoil disturbance must conduct turbidity sampling using a turbidity meter in accordance with Special Condition S4.C. Conslruerion Srormil-wer Generirl Permir Page 154 C. Turbidity/Transparency Sampling Requirements 1. Sampling Methods a. If construction activity involves the disturbance of 5 acres or more, the Permittee must conduct turbidity sampling per Special Condition S4.C. b. If construction activity involves 1 acre or more but fewer than 5 acres of soil disturbance, the Permittee must conduct either transparency sampling or turbidity sampling per Special Condition S4.C. 2. Sampling Frequency a. The Permittee must sample all discharge points at leastt once every calendar week when stormwater (or authorized non-stormwater) discharges from the site or enters any on -site surface waters of the state (for example, a creek running through a site); sampling is not required on sites that disturb less than an acre. b. Samples must be representative of the flow and characteristics of the discharge. c. Sampling is not required when there is no discharge during a calendar week. d. Sampling is not required outside of normal working hours or during unsafe conditions. e. If the Permittee is unable to sample during a monitoring period, the Permittee must include a brief explanation in the monthly Discharge Monitoring Report (DMR). f Sampling is not required before construction activity begins. g. The Permittee may reduce the sampling frequency for temporarily stabilized, inactive sites to once every calendar month. 3. Sampling Locations a. Sampling is required at all points where stonnwater associated with construction activity (or authorized non-stormwater) is discharged off site, including where it enters any on -site surface waters of the state (for example, a creek running through a site). b. The Pennittee may discontinue sampling at discharge points that drain areas of the project that are fully stabilized to prevent erosion. c. The Permittee must identify all sampling point(s) on the SWPPP site map and clearly mark these points in the field with a flag, tape, stake or other visible marker. d. Sampling is not required for discharge that is sent directly to sanitary or combined sewer systems. Consrrucvion Sronmvarer General Permit Page 16 Page I55 e. The Permittee may discontinue sampling at discharge points in areas of the project where the Permittee no longer has operational control of the construction activity. 4, Sampling and Analysis Methods a. The Pernittee performs turbidity analysis with a calibrated turbidity meter (turbidimeter) either on site or at an accredited lab. The Permittee must record the results in the site log book in nephelometric turbidity units (NTUs). b. The Permittee performs transparency analysis on site with a 13/4-inch-diameter, 60-centimeter (cm) -long transparency tube. The Permince will record the results in the site log book in centimeters (cm). Table 4: Monitoring and Reporting Requirements Parameter Unit Analytical Method Sampling Benchmark I Phone Frequency Value Reporting Trigger Value Turbidity NTU SM2130 Weekly, if 25 NTUs 250 NTUs discharging Transparency cm Manufacturer Weekly, if 33 cm 6 cm instructions, or discharging Ecology guidance 5. Turbidity/Transparency Benchmark Values and Reporting Triggers The benchmark value for turbidity is 25 NTUs or less_ The benchmark value for transparency is 33 centimeters (cm). Note: Benchmark values do not apply to discharges to segments of water bodies on Washington State's 303(d) list (Category 5) for turbidity, fine sediment, or phosphorus; these discharges are subject to a numeric effluent limit for turbidity. Refer to Special Condition S8 for more information. a. Turbidity 26 — 249 NTUs, or Transparency 32 — 7 cm: If the discharge turbidity is 26 to 249 NTUs; or if discharge transparency is less than 33 cm, but equal to or greater than 6 cm, the Permittee must: Review the SWPPP for compliance with Special Condition S9 and make appropriate revisions within 7 days of the date the discharge exceeded the benchmark. Immediately begin the process to fully implement and maintain appropriate source control and/or treatment BMPs as soon as possible, addressing the problems within 10 days of the date the discharge exceeded the benchmark. If installation of necessary treatment BMPs is not feasible within 10 days, Ecology may approve additional time when the Permittee requests an extension within the initial 10-day response period. Cmstruction 5lonuuOh'i, (;""O"ill Pennil Page 156 iii. Document BMP implementation and maintenance in the site log book. b. Turbidity 250 NTUs or greater, or Transparency 6 cm or less: If a discharge point's turbidity is 250 NTUs or greater, or if discharge transparency is less than or equal to 6 cm, the Permittee must complete the reporting and adaptive management process described below. i. Telephone or submit an electronic report to the applicable Ecology Region's Environmental Report Tracking System (ERTS) number (or through Ecology's Water Quality Permitting Portal [WQWebPortal] — Permit Submittals when the form is available) within 24 hours, in accordance with Special Condition S5.A. ■ Central Region (Okanogan, Chelan, Douglas, Kittitas, Yakima, Klickitat, Benton): (509) 575-2490 • Eastern Region (Adams, Asotin, Columbia, Ferry, Franklin, Garfield, Grant, Lincoln, Pend Oreille, Spokane, Stevens, Walla Walla, Whitman): (509) 329-3400 • Northwest Region (Kitsap, Snohomish, Island, King, San Juan, Skagit, Whatcom): (425) 649-7000 • Southwest_ Region (Grays Harbor, Lewis, Mason, Thurston, Pierce, Clark, Cowlitz, Skamania, Wahkiakum, Clallam, Jefferson, Pacific): (360)407-6300 Links to these numbers and the ERTS reporting page are located on the following web site: htl Jit�r�v.wa.govlg,��plstnrmvvatcricnnxtnictin�Lindr��.,�Lml. ii. Review the SWPPP for compliance with Special Condition S9 and make appropriate revisions within 7 days of the date the discharge exceeded the benchmark. iii. Immediately begin the process to fully implement and maintain appropriate source control and/or treatment BMPs as soon as possible, addressing the problems within 10 days of the date the discharge exceeded the benchmark. If installation of necessary treatment BMPs is not feasible within 10 days, Ecology may approve additional time when the Permitee requests an extension within the initial 10-day response period. iv. Document BMP implementation and maintenance in the site log book. V. Sample discharges daily until: a) Turbidity is 25 NTUs (or lower); or b) Transparency is 33 cm (or greater); or Construction+ Stornnrater General Permit Pace is Page 157 c) The Permittee has demonstrated compliance with the water quality limit for turbidity: l) No more than 5 NTUs over background turbidity, if background is less than 50 NTUs, or 2) No more than 10% over background turbidity, if background is 50 NTUs or greater; or d) The discharge stops or is eliminated. D. pH Sampling Requirements — Significant Concrete Work or Engineered Soils If constriction activity results in the disturbance of t acre or more, and involves significant concrete work (significant concrete work means greater than 1000 cubic yards poured concrete used over the life of a project ) or the use of recyeled concrete or engineered soils (soil amendments including but not limited to Portland cement -treated base [CTB], cement kiln dust [CKD], or Ely ash), and stormwater from the affected area drains to surface waters of the State or to a storm sewer system that drains to surface waters of the State, the Permittee must conduct pH sampling as set forth below. Note: In addition, discharges to segments of water bodies on Washington State's 303(d) list (Category 5) for high pH are subject to a numeric effluent limit for pH; refer to Special Condition S8. 1. For sites with significant concrete work, the Permittee must begin the pH sampling period when the concrete is first poured and exposed to precipitation, and continue weekly throughout and after the concrete pour and curing period, until stormwater pH is in the range of 6.5 to 8.5 (su). 2. For sites with recycled concrete, the Permittee must begin the weekly pH sampling period when the recycled concrete is first exposed to precipitation and must continue until the recycled concrete is fully stabilized and stormwater pH is in the range of 6.5 to 8.5 (su). 3. For sites with engineered soils, the Permittee must begin the pH sampling period when the soil amendments are first exposed to precipitation and must continue until the area of engineered soils is fully stabilized. 4. During the applicable pl-i monitoring period defined above, the Permittee must obtain a representative sample of stormwater and conduct pH analysis at least once per week. 5. The Permittee must sample pH in the sediment trap/pond(s) or other locations that receive stormwater runoff from the area of significant concrete work or engineered soils before the stormwater discharges to surface waters. 6. The benchmark value for pH is 8.5 standard units. Anytime sampling indicates that pH is 8.5 or greater, the Permittee must either: Cnnslrrrclion SIU17mrater General Periirl! Pwrc 19 Page 158 a. Prevent the high pH water (8.5 or above) from entering storm sewer systems or surface waters; or b. If necessary, adjust or neutralize the high pH water until it is in the range of pH 6.5 to 8.5 (su) using an appropriate treatment BMP such as carbon dioxide (CO2) sparging or dry ice. The Permittee must obtain written approval from Ecology before using any form of chemical treatment other than COz sparging or dry ice. 7. The Permittee must perform pH analysis on site with a calibrated pH meter, pH test kit, or wide range pH indicator paper. The Permittee must record pH sampling results in the site log book. S5. REPORTING AND RECORDKEEPING REQUIREMENTS A. High Turbidity Reporting Anytime sampling performed in accordance with Special Condition S4.0 indicates turbidity has reached the 250 NTUs or more (or transparency less than or equal to 6 cm) high turbidity reporting level, the Permittee must either call the applicable Ecology Region's Environmental Report Tracking System (ERTS) number by phone within 24 hours of analysis or submit an electronic ERTS report (or submit an electronic report through Ecology's Water Quality Permitting Portal (WQWebPortal) — Permit Submittals when the form is available). See the CSWGP web site for links to ERTS and the WQWebPortal: httg.//wnww.ecy.wa.gov!programs;'► q/. rmwaterJconstruction! index.html. Also, see phone numbers in Special Condition S4.C.5.b.i. B. Discharge Monitoring Reports (DMRs) Permittees required to conduct water quality sampling in accordance with Special Conditions S4.0 (Turbidity/Transparency), S4.13 (pH), S8 (303[d]ITMDL sampling), and/or G 13 (Additional Sampling) must submit the results to Ecology. Permittees must submit monitoring data using Ecology's WQWebDMR web application accessed through Ecology's Water Quality Permitting Portal. To find out more information and to sign up for WQWebDMR go to: http.;//%vww.ecy.wa,aov/procrani.cd wofnerm iti/Tiariti'nortal. htm I . Permittees unable to submit electronically (for example, those who do not have an internet connection) must contact Ecology to request a waiver and obtain instructions on how to obtain a paper copy DMR at: Department of Ecology Water Quality Program - Construction Stormwater PO Box 47696 Olympia, Washington 98504-7696 Permittees who obtain a waiver not to use WQWebDMR must use the forms provided to them by Ecology; submittals must be mailed to the address above. Permittees shall Construction S'lornnrutcr General Pernnir Page'_(] Page 159 submit DMR forms to be received by Ecology within 15 days following the end of each month. If there was no discharge during a given monitoring period, all Permittees must submit a DMR as required with "no discharge" entered in place of the monitoring results. DMRs are required for the full duration of pomiit coverage (from issuance date to termination). For more information, contact Ecology staff using information provided at the following web site: ww►t.cC .►va. ovi roa mslw 1 ermits/ ar''sslcontacts.himl. C. Records Retention The Permittee must retain records of all monitoring information (site log book, sampling results, inspection reports/checklists, etc.), Stormwater Pollution Prevention Plan, copy of the permit coverage letter (including Transfer of Coverage documentation), and any other documentation of compliance with permit requirements for the entire life of the construction project and for a minimum of three years following the termination of permit coverage. Such information must include all calibration and maintenance records, and records of all data used to complete the application for this permit. This period of retention must be extended during the course of any unresolved litigation regarding the discharge of pollutants by the Permittee or when requested by Ecology. D. Recording Results For each measurement or sample taken, the Permittee trust record the following information: t. Date, place, method, and time of sampling or measurement. 2. The first and last name of the individual who performed the sampling or measurement. 3. The date(s) the analyses were performed. 4. The first and last name of the individual who performed the analyses. 5. The analytical techniques or methods used. 6. The results of all analyses. E. Additional Monitoring by the Permittee If the Permittee monitors any pollutant more frequently than required by this permit using test procedures specified by Special Condition S4 of this permit, the results of this monitoring must be included in the calculation and reporting of the data submitted in the Permittee's DMR. F. Noncompliance Notification In the event the Permittee is unable to comply with any part of the terms and conditions of this permit, and the resulting noncompliance may cause a threat to human health or the environment (such as but not limited to spills of fuels or other materials, catastrophic pond or slope failure, and discharges that violate water quality standards), or exceed Con iritetion Slornnrafer General Pernrir Page 21 Page 160 numeric effluent limitations (see S8. Discharges to 303(d) or TMDL Waterbodies), the Permittee must, upon becoming aware of the circumstance: L. Notify Ecology within 24-hours of the failure to comply by calling the applicable Regional office ERTS phone number (refer to Special Condition S4.C.5.b.i. or wAk,w. c c v. ova. soul pro., ra m s/ wglsto rinwate rlc o ns tract ion Iturbi d ity. html for Regional ERTS phone numbers). 2. Immediately take action to prevent the discharge/pollution, or otherwise stop or correct the noncompliance, and, if applicable, repeat sampling and analysis of any noncompliance immediately and submit the results to Ecology within five (5) days of becoming aware of the violation. 3. Submit a detailed written report to Ecology within five (5) days, of the time the Permittee becomes aware of the circumstances, unless requested earlier by Ecology. The report must be submitted using Ecology's Water Quality Permitting Portal (WQWebPortal) - Permit Submittals, unless a waiver from electronic reporting has been granted according to S5.B. The report must contain a description of the noncompliance, including exact dates and times, and if the noncompliance has not been corrected, the anticipated time it is expected to continue; and the steps taken or planned to reduce, eliminate, and prevent reoccurrence of the noncompliance. The Permittee must report any unanticipated bypass and/or upset that exceeds any effluent limit in the permit in accordance with the 24-hour reporting requirement contained in 40 C.F.R. 122.41(1)(6). Compliance with these requirements does not relieve the Permittee from responsibility to maintain continuous compliance with the terms and conditions of this permit or the resulting liability for failure to comply. Upon request of the Permittee. Ecology may waive the requirement for a written report on a case -by - case basis, if the immediate notification is received by Ecology within 24 hours. G. Access to Plans and Records L. The Permittee must retain the following permit documentation (plans and records) on site, or within reasonable access to the site, for use by the operator or for on -site review by Ecology or the local jurisdiction: a. General Permit b. Permit Coverage Letter c. Stormwater Pollution Prevention Plan (SWPPP) d. Site Log Book 2. The Permittee must address written requests for plans and records listed above (Special Condition S5.G.1) as follows: Construction Stonmratcr Generol Perniil Page ?'2 Page 161 a. The Permittee must provide a copy of plans and records to Ecology within 14 days of receipt of a written request from Ecology. b. The Permittee must provide a copy of plans and records to the public when requested in writing. Upon receiving a written request from the public for the Permittee's plans and records, the Permittee must either: i. Provide a copy of the plans and records to the requester within 14 days of a receipt of the written request; or ii. Notify the requester within 10 days of receipt of the written request of the location and times within normal business hours when the plans and records may be viewed; and provide access to the plans and records within 14 days of receipt of the written request; or iii. Within 14 days of receipt of the written request, the Permittee may submit a copy of the plans and records to Ecology for viewing and/or copying by the requester at an Ecology office, or a mutually agreed location. If plans and records are viewed and/or copied at a location other than at an Ecology office, the Permittee will provide reasonable access to copying services for which a reasonable fee may be charged. The Permittee must notify the requester within 10 days of receipt of the request where the plans and records may be viewed and/or copied. S6. PERMIT FEES The Permittee must pay permit fees assessed by Ecology. Fees for stormwater discharges covered under this permit are established by Chapter 173-224 WAC. Ecology continues to assess permit fees until the permit is terminated in accordance with Special Condition S 10 or revoked in accordance with General Condition G5. S7. SOLID AND LIQUID WASTE DISPOSAL The Permittee must handle and dispose of solid and liquid wastes generated by construction activity, such as demolition debris, construction materials, contaminated materials, and waste materials from maintenance activities, including liquids and solids front cleaning catch basins and other stormwater facilities, in accordance with: A. Special Condition S3, Compliance with Standards B. WAC 173-216-110 C. Other applicable regulations S8. DISCHARGES TO 303(d) OR TMDL WATERBODIES A. Sampling and Numeric Effluent Limits For Certain Discharges to 303(d)-listed Waterbodies Consu•ralion slornnrarerGeneral perniir Page 23 Page 162 I . Permittees who discharge to segments of waterbodies listed as impaired by the State of Washington under Section 303(d) of the Clean Water Act for turbidity, fine sediment, high pH, or phosphorus, must conduct water quality sampling according to the requirements of this section, and Special Conditions S4.C.2.b-f and M.C.3.b-d, and must comply with the applicable numeric effluent limitations in SS.0 and S&D. 2. All references and requirements associated with Section 303(d) of the Clean Water Act mean the most current listing by Ecology of impaired waters (Category 5) that exists on January 1, 2016, or the date when the operator's complete permit application is received by Ecology, whichever is later. B. Limits on Coverage for New Discharges to TMDL or 303(d)-listed Waters Operators of construction sites that discharge to a TMDL or 303(d)-listed waterbody are not eligible for coverage under this permit unless the operator: 1. Prevents exposing stormwater to pollutants for which the waterbody is impaired, and retains documentation in the SWPPP that details procedures taken to prevent exposure on site; or 2. Documents that the pollutants for which the waterbody is impaired are not present at the site, and retains documentation of this finding within the SWPPP; or 3. Provides Ecology with data indicating the discharge is not expected to cause or contribute to an exeeedance of a water quality standard, and retains such data on site with the SWPPP. The operator must provide data and other technical information to Ecology that sufficiently demonstrate: a. For discharges to waters without an EPA -approved or -established TMDL, that the discharge of the pollutant for which the water is impaired will meet in - stream water quality criteria at the point of discharge to the waterbody; or b. For discharges to waters with an EPA -approved or -established TMDL, that there is sufficient remaining wasteload allocation in the TMDL to allow construction stormwater discharge and that existing dischargers to the waterbody are subject to compliance schedules designed to bring the waterbody into attainment with water quality standards. Operators of construction sites are eligible for coverage under this permit if Ecology issues permit coverage based upon an affirmative determination that the discharge will not cause or contribute to the existing impairment. C. Sampling and Numeric Effluent Limits for Discharges to Water Bodies on the 303(d) List for Turbidity, Fine Sediment, or Phosphorus 1. Permittees who discharge to segments of water bodies on the 303(d) list (Category 5) for turbidity, tine sediment, or phosphorus must conduct turbidity sampling in accordance with Special Condition S4.C.2 and comply with either of the numeric effluent limits noted in Table 5 below. Conslrurrion Sturnnrurcr General Pennil Page 24 Page 163 2. As an alternative to the 25 NTUs effluent limit noted in Table 5 below (applied at the point where stormwater (or authorized non-stormwarer] is discharged off -site), Permittees may choose to comply with the surface water quality standard for turbidity. The standard is: no more than 5 NTIJs over background turbidity when the background turbidity is 50 NTUs or less, or no more than a 10% increase in turbidity when the background turbidity is more than 50 NTUs, In order to use the water quality standard requirement, the sampling must take place at the fallowing locations: a. Background turbidity in the 303(d)-listed receiving water immediately upstream (upgradient) or outside the area of influence of the discharge. b. Turbidity at the point of discharge into the 303(d)-listed receiving water, inside the area of influence of the discharge. 3. Discharges that exceed the numeric effluent limit for turbidity constitute a violation of this permit. 4. Permittees whose discharges exceed the numeric effluent limit shall sample discharges daily until the violation is corrected and comply with the non- compliance notification requirements in Special Condition S51. Table 5: Turbidity, Fine Sediment & Phosphorus Sampling and Limits for 303(d)-Listed Waters Parameter identified In 303(d) listing Parameter Sampled Unit Analytical Method Sampling Frequency Numeric Effluent Limit' • Turbidity Turbidity NTU SM2130 Weekly, if 25 NTUs, at the • Fine Sediment discharging point where • Phosphorus stormwater is discharged from the site; OR In compliance with the surface water quality standard for turbidity (S8.C.2.a) 'Permittees subject to a numeric effluent limit for turbidity may, at their discretion, choose either numeric effluent limitation based on site -specific considerations including, but not limited to, safety, access and convenience. D. Discharges to Water Bodies on the 303(d) List for High pH l . Permittees who discharge to segments of water bodies on the 303(d) list (Category 5) for high pH must conduct pH sampling in accordance with the table below, and comply with the numeric effluent limit of pH 6.5 to 8.5 su (Table 6). P i'C _' 5 Page 164 Table 6: pH Sampling and Limits for 303(d)-Listed Waters Parameter identified in Parameter Analytical Sampling Numeric Effluent 303(d) listing Sampled/Units Method Frequency Limit High pH pH /Standard pH meter Weekly, if In the range of 6.5 Units discharging — 8.5 2. At the Permittee's discretion, compliance with the limit shall be assessed at one of the following locations: a. Directly in the 303(d)-listed waterbody segment, inside the immediate area of influence of the discharge; or b. Alternatively, the Permittee may measure pH at the point where the discharge leaves the construction site, rather than in the receiving water. 3. Discharges that exceed the numeric effluent limit for pH (outside the range of 6.5 — 8.5 su) constitute a violation of this permit. 4. Permittees whose discharges exceed the numeric effluent limit shall sample discharges daily until the violation is corrected and comply with the non- compliance notification requirements in Special Condition S51. E. Sampling and Limits for Sites Discharging to Waters Covered by a TMDL or Another Pollution Control Plan 1. Discharges to a waterbody that is subject to a Total Maximum Daily Load (TMDL) for turbidity, fine sediment, high pH, or phosphorus must be consistent with the TMDL. Refer to htir)://Avwi%,.ccv.wa.gov/programs/%v(i/tmdl/ T L51i Wriav`TNlDLbvWria.html for more information on TMDLs. a. Where an applicable TMDL sets specific waste load allocations or requirements for discharges covered by this permit, discharges must be consistent with any specific waste load allocations or requirements established by the applicable TMDL. i. The Permittee must sample discharges weekly or as otherwise specified by the TMDL to evaluate compliance with the specific waste load allocations or requirements. ii. Analytical methods used to meet the monitoring requirements must conform to the latest revision of the Guidelines Establishing Test Procedures for the Analysis of Pollutants contained in 40 CFR Part 136. Turbidity and pH methods need not be accredited or registered unless conducted at a laboratory which must otherwise be accredited or registered. b. Where an applicable TMDL has established a general waste load allocation for construction stormwater discharges, but has not identified specific requirements, Cuatih ur�rn�i SIU1-nn1'W0- Gtw ovi Pei-mi( Pigc 20 Page 165 compliance with Special Conditions S4 (Monitoring) and S9 (SWPPPs) will constitute compliance with the approved TMDL. c. Where an applicable TMDL has not specified a waste load allocation for construction stormwater discharges, but has not excluded these discharges, compliance with Special Conditions S4 (Monitoring) and S9 (SWPPPs) will constitute compliance with the approved TMDL_ d. Where an applicable TMDL specifically precludes or prohibits discharges from construction activity, the operator is not eligible for coverage under this permit. Applicable TMDL means a TMDL for turbidity, fine sediment, high pH, or phosphorus that is completed and approved by EPA before January 1, 2016, or before the date the operator's complete permit application is received by Ecology, whichever is later. TMDLs completed after the operator's complete permit application is received by Ecology become applicable to the Permittee only if they are imposed through an administrative order by Ecology, or through a modification of permit coverage. S9. STORNiWATER POLLUTION PREVENTION PLAN The Permittee must prepare and properly implement an adequate Stormwater Pollution Prevention Plan (SWPPP) for construction activity in accordance with the requirements of this permit beginning with initial soil disturbance and until final stabilization. A, The Permittee's SWPPP must meet the following objectives: 1. To implement best management practices (BMPs) to prevent erosion and sedimentation, and to identify, reduce, eliminate or prevent stormwater contamination and water pollution from construction activity. 2. To prevent violations of surface water quality, ground water quality, or sediment management standards. 3. To control peak volumetric flow rates and velocities of stormwater discharges. B. General Requirements l . The SWPPP must include a narrative and drawings. All BMPs must be clearly referenced in the narrative and marked on the drawings. The SWPPP narrative must include documentation to explain and justify the pollution prevention decisions made for the project. Documentation must include: a. information about existing site conditions (topography, drainage, soils, vegetation, etc.). b. Potential erosion problem areas. c. The 13 elements of a SWPPP in Special Condition S9.13.1-13, including BMPs used to address each element. 11-1fC111)11 Slw mtru r L'r• GOIL'7W/ PCI.1;Ii( f aye ?7 Page 166 & Construction phasing/sequence and general BMP implementation schedule. e. The actions to be taken if BMP performance goals are not achieved —for example, a contingency plan for additional treatment and/or storage of stormwater that would violate the water quality standards if discharged. f. Engineering calculations for ponds, treatment systems, and any other designed structures. 2. The Permittee must modify the SWPPP if, during inspections or investigations conducted by the owner/operator, or the applicable local or state regulatory authority, it is determined that the SWPPP is, or would be, ineffective in eliminating or significantly minimizing pollutants in stormwater discharges from the site. The Pennittee must then: a. Review the SWPPP for compliance with Special Condition S9 and make appropriate revisions within 7 days of the inspection or investigation. b. Immediately begin the process to fully implement and maintain appropriate source control and/or treatment BMPs as soon as possible, addressing the problems no later than 10 days from the inspection or investigation. If installation of necessary treatment BMPs is not feasible within 10 days, Ecology may approve additional time when an extension is requested by a Permittee within the initial 10-day response period. c. Document BMP implementation and maintenance in the site log book. The Permittee must modify the SWPPP whenever there is a change in design, construction, operation, or maintenance at the construction site that has, or could have, a significant effect on the discharge of pollutants to waters of the State. C. Stormwater Best Management Practices (BMPs) BMPs must be consistent with: l . S.tormwater Management Manual for Western Washington (most current approved edition at the time this permit was issued), for sites west of the crest of the Cascade Mountains; or 2. Stormwater Management Manual for Eastern Washington (most current approved edition at the time this permit was issued), for sites east of the crest of the Cascade Mountains; or 3. Revisions to the manuals listed in Special Condition S9.C.1. & 2., or other stormwater management guidance documents or manuals which provide an equivalent level of pollution prevention, that are approved by Ecology and incorporated into this permit in accordance with the permit modification requirements of WAC 173-226-230; or Consiruc•iiml S7urmwO10-G"Hered I'ermii P'i'c Z\ Page 167 4. Documentation in the SWPPP that the BMPs selected provide an equivalent level of pollution prevention, compared to the applicable Stormwater Management Manuals, including: a. The technical basis for the selection of all stormwater BMPs (scientific, technical studies, and/or modeling) that support the performance claims for the BMPs being selected. b. An assessment of how the selected BMP will satisfy AKART requirements and the applicable federal technology -based treatment requirements under 40 CFR part 125.3. D. SWPPP — Narrative Contents and Requirements The Permittee must include each of the 13 elements below in Special Condition S9.D.1-13 in the narrative of the SWPPP and implement them unless site conditions render the element unnecessary and the exemption from that element is clearly justified in the SWPPP. 1. Preserve Vegetation/Mark Clearing Limits a. Before beginning land -disturbing activities, including clearing and grading, clearly mark all clearing limits, sensitive areas and their buffers, and trees that are to be preserved within the construction area. b. Retain the duff layer, native topsoil, and natural vegetation in an undisturbed state to the maximum degree practicable. 2. Establish Construction Access a. Limit construction vehicle access and exit to one route, if possible. b. Stabilize access points with a pad of quarry spalls, crushed rock, or other equivalent BMPs, to minimize tracking sediment onto roads. c. Locate wheel wash or tire baths on site, if the stabilized construction entrance is not effective in preventing tracking sediment onto roads. d. if sediment is tracked off site, clean the affected roadway thoroughly at the end of each day, or more frequently as necessary (for example, during wet weather). Remove sediment from roads by shoveling, sweeping, or pickup and transport of the sediment to a controlled sediment disposal area. e. Conduct street washing only after sediment removal in accordance with Special Condition S9.D.2.d. Control street wash wastewater by pumping back on site or otherwise preventing it from discharging into systems tributary to waters of the State. 3. Control Flow Rates a. Protect properties and waterways downstream of development sites from erosion and the associated discharge of turbid waters due to increases in the C'unslrrrcrion Slonim-w er General Purnrir Page ?9 Page 168 velocity and peak volumetric flow rate of stormwater runoff from the project site, as required by local plan approval authority. b. Where necessary to comply with Special Condition S9.D.3.a, construct stormwater retention or detention facilities as one of the first steps in grading. Assure that detention facilities function properly before constricting site improvements (for example, impervious surfaces). c. If permanent infiltration ponds are used for flow control during construction, protect these facilities from siltation during the construction phase. 4. Install Sediment Controls The Permittee must design, install and maintain effective erosion controls and sediment controls to minimize the discharge of pollutants. At a minimum, the Permittee must design, install and maintain such controls to: a. Construct sediment control BMPs (sediment ponds, traps, filters, infiltration facilities, etc.) as one of the first steps in grading. These BMPs must be functional before other land disturbing activities take place. b. Minimize sediment discharges from the site. The design, installation and maintenance of erosion and sediment controls must address factors such as the amount, frequency, intensity and duration of precipitation, the nature of resulting stormwater runoff, and soil characteristics, including the range of soil particle sizes expected to be present on the site. c. Direct stormwater runoff from disturbed areas through a sediment pond or other appropriate sediment removal BMP, before the runofr leav es. a con stru ct ion Site or before discharge to an infiltration facility. Runoff from fully stabilized areas may be discharged without a sediment removal BMP, but must meet the flow control performance standard of Special Condition S9.13.3.a. d. Locate BMPs intended to trap sediment on site in a manner to avoid interference with the movement of juvenile salmonids attempting to enter off -channel areas or drainages. e. Provide and maintain natural buffers around surface waters, direct stormwater to vegetated areas to increase sediment removal and maximize stormwater infiltration, unless infeasible. f. Where feasible, design outlet structures that withdraw impounded stormwater from the surface to avoid discharging sediment that is still suspended lower in the water column. 5. Stabilize Soils a. The Permittee must stabilize exposed and unworked soils by application of effective BMPs that prevent erosion. Applicable BMPs include, but are not limited to: temporary and permanent seeding, sodding, mulching, plastic covcrittg, erosion control fabrics and matting, soil application of polyacrylamide CunaYrucrion Stornnru[c r General fermi! Ng,c Page 169 (PAM), the early application of gravel base on areas to be paved, and dust control. b. The Pennittee must control stormwater volume and velocity within the site to minimize soil erosion. c. The Permittee must control stormwater discharges, including both peak flow rates and total stormwater volume, to minimize erosion at outlets and to minimize downstream channel and stream bank erosion. d. Depending on the geographic location of the project, the Permittee must not allow soils to remain exposed and un►+orked for more than the time periods set forth below to prevent erosion: West of the Cascade Mountains Crest During the dry season (May 1 - September 30): 7 days During the wet season (October I - April 30): 2 days East of the Cascade Mountains Crest, except for Central Basin* During the dry season (July I - September 30): 10 days During the wet season (October 1 - June 30): 5 days The Central Basin*, East of the Cascade Mountains Crest During the dry season (July 1 - September 30): 30 days During the wet season (October 1 - June 30): 15 days *Note: The Central Basin is defined as the portions of Eastern Washington with mean annual precipitation of less than 12 inches. e. The Permittee must stabilize soils at the end of the shift before a holiday or weekend if needed based on the weather forecast. f. The Pennittee must stabilize soil stockpiles from erosion, protected with sediment trapping measures, and where possible, be located away from storm drain inlets, waterways, and drainage channels. g. The Permittee must minimize the amount of soil exposed during construction activity. h. The Permittee must minimize the disturbance of steep slopes. i. The Permittee must minimize soil compaction and, unless infeasible, preserve topsoil. 6. Protect Slopes a. The Permittee must design and construct cut -and -fill slopes in a manner to minimize erosion. Applicable practices include, but are not limited to, reducing continuous length of slope with terracing and diversions, reducing slope steepness, and roughening slope surfaces (for example, track walking). Construciion Stornnrater General Perini( Page 31 Page 170 b. The Permittee must divert off -site stormwater (run-on) or ground water away from slopes and disturbed areas with interceptor dikes, pipes, and/or swales. Off -site stormwater should be managed separately from stormwater generated on the site. c. At the top of slopes, collect drainage in pipe slope drains or protected channels to prevent erosion. West of the Cascade Mountains Crest: Temporary pipe slope drains must handle the peak l0-minute flow rate from a Type 1 A, 10-year, 24-hour frequency storm for the developed condition. Alternatively, the W-year, I -hour flow rate predicted by an approved continuous runoff model, increased by a factor of l .6, may be used. The hydrologic analysis must use the existing land cover condition for predicting flow rates from tributary areas outside the project limits. For tributary areas on the project site, the analysis must use the temporary or permanent project land cover condition, whichever will produce the highest flow rates. If using the Western Washington Hydrology Model (WWHM) to predict flows, bare soil areas should be modeled as "landscaped area." ii. East of the Cascade Mountains Crest: Temporary pipe slope drains must handle the expected peak flow rate from a 6-month, 3-hour storm for the developed condition, referred to as the short duration storm. d. Place excavated material on the uphill side of trenches, consistent with safety and space considerations. e. Place check dams at regular intervals within constructed channels that are cut down a slope. 7. Protect Drain Inlets a. Protect all storm drain inlets made operable during construction so that stormwater runoff does not enter the conveyance system without first being filtered or treated to remove sediment. b. Clean or remove and replace inlet protection devices when sediment has filled one-third of the available storage (unless a different standard is specified by the product manufacturer). 8. Stabilize Channels and Outlets a. Design, construct and stabilize all on -site conveyance channels to prevent erosion from the following expected peak flows: West of the Cascade Mountains Crest: Channels must handle the peak 10-minute flow rate from a Type 1 A, 10-year, 24-hour frequency storm for the developed condition. Alternatively, the 10-year, 1-hour flow rate indicated by an approved continuous runoff model, increased by a factor of 1.6, may be used. The hydrologic analysis must use the existing land Construction Siormn crier Generul Pernril Page 3? Page 171 cover condition for predicting flow rates from tributary areas outside the project limits. For tributary areas on the project site, the analysis must use the temporary or permanent project land cover condition, whichever will produce the highest flow rates. If using the WWHM to predict flows, bare soil areas should be modeled as "landscaped area." ii. East of the Cascade Mountains Crest: Channels must handle the expected peak flow rate from a 6-month, 3-hour storm for the developed condition, referred to as the short duration storm. b. Provide stabilization, including armoring material, adequate to prevent erosion of outlets, adjacent stream banks, slopes, and downstream reaches at the outlets of all conveyance systems. 9. Control Pollutants Design, install, implement and maintain effective pollution prevention measures to minimize the discharge of pollutants. The Permittee must: a. Handle and dispose of all pollutants, including waste materials and demolition debris that occur on site in a manner that does not cause contamination of stormwater. b. Provide cover, containment, and protection from vandalism for all chemicals, liquid products, petroleum products, and other materials that have the potential to pose a threat to human health or the environment. 4n-site fueling tanks must include secondary containment. Secondary containment means placing tanks or containers within an impervious structure capable of containing 110% of the volume contained in the largest tank within the containment structure. Double - walled tanks do not require additional secondary containment. c. Conduct maintenance, fueling, and repair of heavy equipment and vehicles using spill prevention and control measures. Clean contaminated surfaces immediately following any spill incident. d. Discharge wheel wash or tire bath wastewater to a separate on -site treatment system that prevents discharge to surface water, such as closed -loop recirculation or upland land application, or to the sanitary sewer with local sewer district approval, e. Apply fertilizers and pesticides in a manner and at application rates that will not result in loss of chemical to stormwater runoff. Follow manufacturers' Libel requirements for application rates and procedures. f. Use 13MPs to prevent contamination of stormwater runoff by pH -modifying sources. The sources for this contamination include, but are not limited to: bulk cement, cement kiln dust, fly ash, new concrete washing and curing waters, recycled concrete stockpiles, waste streams generated from concrete grinding and sawing, exposed aggregate processes, dewatering concrete vaults, concrete Constraclion S7ornnrnier Generul Pernlif Page 33 Page 172 pumping and mixer washout waters. (Also refer to the definition for "concrete wastewater" in Appendix A --Definitions.) g. Adjust the pH of stormwater or authorized non-stormwater if necessary to prevent an excecdance of groundwater and/or surface water quality standards. h. Assure that washout of concrete trucks is performed off -site or in designated concrete washout areas only. Do not wash out concrete trucks or concrete handling equipment onto the ground, or into stortu drains, open ditches, streets. or streams. Do not dump excess concrete on site, except in designated concrete washout areas. Concrete spillage or concrete discharge to surface waters of the State is prohibited. i. Obtain written approval from Ecology before using any chemical treatment, with the exception of COz or dry ice used to adjust pH. j. Uncontaminated water from water -only based shaft drilling for construction of building, road, and bridge foundations may be infiltrated provided the wastewater is managed in a way that prohibits discharge to surface waters. Prior to infiltration, water from water -only based shaft drilling that comes into contact with curing concrete must be neutralized until pH is in the range of 6.5 to 8.5 (su). 10. Control Dewatering a. Permittees must discharge foundation, vault, and trench dewatering water, which have characteristics similar to stormwater runoff at the site, into a controlled conveyance system before discharge to a sediment trap or sediment pond. b. Permittees may discharge clean, non -turbid dewatering water, such as well- poitit ground water, to systems tributary to, or directly into surface waters of the State, as specified in Special Condition S9.13.8, provided the dewatering flow does not cause erosion or flooding of receiving waters. Do not route clean dewatering water through stormwater sediment ponds. Note that "surface waters of the State" may exist on a construction site as well as off site; for example, a creek running through a site. c. Other dewatering treatment or disposal options may include: i. infiltration. ii. Transport off site in a vehicle, such as a vacuum flush truck, for legal disposal in a manner that does not pollute state waters. iii. Ecology -approved on -site chemical treatment or other suitable treatment technologies (see S9.D.9.i, regarding chemical treatment written approval). iv. Sanitary or combined sewer discharge with local sewer district approval, if there is no other option. Cunsuvrliox Slormtraier General Permit Page ,d Page 173 V. Use of a sedimentation bag with discharge to a ditch or swale for small volumes of localized dewatering. d. Permittees must handle highly turbid or contaminated dewatering water separately from stormwater. 11. Maintain BMPs a. Permittees must maintain and repair all temporary and permanent erosion and sediment control BMPs as needed to assure continued performance of their intended function in accordance with BMP specifications. b. Permittees must remove all temporary erosion and sediment control BMPs within 30 days after achieving final site stabilization or after the temporary BMPs are no longer needed. 12. Manage the Project a. Phase development projects to the maximum degree practicable and take into account seasonal work limitations. b. Inspection and monitoring — Inspect, maintain and repair all BMPs as needed to assure continued performance of their intended function. Conduct site inspections and monitoring in accordance with Special Condition S4. c. Maintaining an updated construction SWPPP — Maintain, update, and implement the SWPPP in accordance with Special Conditions S3, S4 and S9. 13. Protect Low Impact Development (LID) BMPs The primary purpose of LID BMPs/On-site LID Stormwater Management BMPs is to reduce the disruption of the natural site hydrology. LID BMPs are permanent facilities. a. Permittees must protect all Bioretention and Rain Garden facilities from sedimentation through installation and maintenance of erosion and sediment control BMPs on portions of the site that drain into the Bioretention and/or Rain Garden facilities. Restore the facilities to their fully functioning condition if they accumulate sediment during construction. Restoring the Facility must include removal of sediment and any sediment -laden Bioretention/Rain Garden soils, and replacing the removed soils with soils meeting the design specification. b. Permittees must maintain the infiltration capabilities of Bioretention and Rain Garden facilities by protecting against compaction by construction equipment and foot traffic. Protect completed lawn and landscaped areas from compaction due to construction equipment. c. Permittees must control erosion and avoid introducing sediment from surrounding land uses onto permeable pavements. Do not allow muddy Collso-[Iclion Sloollwater Gelreral Perniir Page 3� Page 174 construction equipment on the base material or pavement. Do not allow sediment -laden runoff onto permeable pavements. d. Permittees must clean permeable pavements fouled with sediments or no longer passing an initial infiltration test using local stormwater manual methodology or the manufacturer's procedures. e. Permittees must keep all heavy equipment off existing soils undcr LID facilities that have been excavated to final grade to retain the infiltration rate of the soils. E. SWPPP — Map Contents and Requirements The Permittee's SWPPP must also include a vicinity map or general location map (for example, a USGS quadrangle map, a portion of a county or city map, or other appropriate map) with enough detail to identify the location of the construction site and receiving waters within one mile of the site. The SWPPP must also include a legible site map (or maps) showing the entire construction site. The following features must be identified, unless not applicable due to site conditions: 1. The direction of north, property lines, and existing structures and roads. 2. Cut and fill slopes indicating the top and bottom of slope catch lines. 3. Approximate slopes, contours, and direction of stormwater flow before and after major grading activities. 4. Areas of soil disturbance and areas that will not be disturbed. 5. Locations of structural and nonstructural controls (BMPs) identified in the SWPPP. 6. Locations of off -site material, stockpiles, waste storage, borrow areas, and vehicle/equipment storage areas. 7. Locations of all surface water bodies, including wetlands. 8. Locations where stormwater or non-stormwater discharges off -site and/or to a surface waterbody, including wetlands. 9. Location of water quality sampling station(s), if sampling is required by state or local permitting authority. 10. Areas where final stabilization has been accomplished and no further construction - phase permit requirements apply. 11. Location or proposed location of LID facilities. Conslrnrlion Siorimniter Genera/ Pern+il Page 36 Page 175 S10. NOTICE OF TERMINATION A. The site is eligible for termination of coverage when it has met any of the following conditions: 1. The site has undergone final stabilization, the Permittee has removed all temporary BMPs (except biodegradable BMPs. clearly manufactured with the intention for the material to be left in place and not interfere with maintenance or land use). and all stormwater discharges associated with construction activity have been eliminated; or 2. All portions of the site that have not undergone final stabilization per Special Condition S 10.A.1 have been sold and/or transferred (per General Condition G9), and the Permittee no longer has operational control of the construction activity; or 3. For residential construction only, the Permittee has completed temporary stabilization and the homeowners have taken possession of the residences. B. When the site is eligible for termination, the Permittee must submit a complete and accurate Notice of Termination (NOT) form, signed in accordance with General Condition G2, to: Department of Ecology Water Quality Program — Construction Stormwater PO Box 47696 Olympia, Washington 98504-7696 When an electronic termination form is available, the Permittee may choose to submit a complete and accurate Notice of Termination (NOT) form through the Water Quality Permitting Portal rather than mailing a hardcopy as noted above. The termination is effective on the thirty-first calendar day following the date Ecology receives a complete NOT form, unless Ecology notifies the Permittee that the termination request is denied because the Permittee has not met the eligibility requirements in Special Condition S 10.A. Permittees are required to comply with all conditions and effluent limitations in the permit until the permit has been terminated. Permittees transferring the property to a new property owner or operator/Permittee are required to complete and submit the Notice of Transfer form to Ecology, but are not required to submit a Notice of Termination form for this type of transaction. C'un.cmucfhor Stornnrurer Generol Perruil P'l_e 37 Page 176 GENERAL CONDITIONS GI. DISCHARGE VIOLATIONS All discharges and activities authorized by this general permit must be consistent with the terms and conditions of this general permit. Any discharge of any pollutant more frequent than or at a level in excess of that identified and authorized by the general pen -nit must constitute a violation of the terms and conditions of this permit. G2. SIGNATORY REQUIREMENTS A. All permit applications must bear a certification of correctness to be signed: I . In the case of corporations, by a responsible corporate officer; 2. In the case of a partnership, by a general partner of a partnership; 3. In the case of sole proprietorship, by the proprietor; or 4. In the case of a municipal, state, or other public facility, by either a principal executive officer or ranking elected official. B. All reports required by this permit and other information requested by Ecology (including NON. NOTs, and Transfer of Coverage forms) must be signed by a person described above or by a duly authorized representative of that person. A person is a duly authorized representative only if: I . The authorization is made in writing by a person described above and submitted to Ecology. 2. The authorization specifies either an individual or a position having responsibility for the overall operation of the regulated facility, such as the position of plant manager, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters. C. Changes to authorization. If an authorization under paragraph G2.13.2 above is no longer accurate because a different individual or position has responsibility for the overall operation of the facility, a new authorization satisfying the requirements of paragraph G2.13.2 above must be submitted to Ecology prior to or together with any reports, information, or applications to be signed by an authorized representative. D. Certification. Any person signing a document under this section must make the following certification: "I certify under penalty of law, that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering information, the information submitted is, to the best of my C'on.virariiun S'loomrurer General Permit Page 38 Page 177 knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations." G3. RIGHT OF INSPECTION AND ENTRY The Permittee must allow an authorized representative of Ecology, upon the presentation of credentials and such other documents as may be required by law: A. To enter upon the premises where a discharge is located or where any records are kept under the terms and conditions of this permit. B. To have access to and copy — at reasonable times and at reasonable cost — any records required to be kept under the terms and conditions of this permit. C. To inspect — at reasonable times — any facilities, equipment (including monitoring and control equipment), practices, methods, or operations regulated or required under this permit. D. To sample or monitor — at reasonable times — any substances or parameters at any location for purposes of assuring permit compliance or as otherwise authorized by the Clean Water Act. G4. GENERAL PERMIT MODIFICATION AND REVOCATION This permit may be modified, revoked and reissued, or terminated in accordance with the provisions of Chapter 173-226 WAC. Grounds for modification, revocation and reissuance, or termination include, but are not limited to, the following: A. When a change occurs in the technology or practices for control or abatement of pollutants applicable to the category of dischargers covered under this permit. B. When effluent limitation guidelines or standards are promulgated pursuant to the CWA or Chapter 90.48 RCW, for the category of dischargers covered under this permit. C. When a water quality management plan containing requirements applicable to the category of dischargers covered under this permit is approved, or D. When information is obtained that indicates cumulative effects on the environment from dischargers covered under this permit are unacceptable. G5. REVOCATION OF COVERAGE UNDER THE PERMIT Pursuant to Chapter 43.21 B RCW and Chapter 173-226 WAC, the Director may terminate coverage for any discharger under this permit for cause. Cases where coverage may be terminated include, but are not limited to, the following: A. Violation of any term or condition of this permit. B. Obtaining coverage under this permit by misrepresentation or failure to disclose fully all relevant facts. Con,clruclion Storinivaier Gel70'Ul l'irmil Pagc 39 Page 178 C. A change in any condition that requires either a temporary or permanent reduction or elimination of the permitted discharge. D. Failure or refusal of the Permittee to allow entry as required in RCW 90.48.090. E. A determination that the permitted activity endangers human health or the environment, or contributes to water quality standards violations. F. Nonpayment of permit fees or penalties assessed pursuant to RCW 90.48.465 and Chapter 173-224 WAC. G. Failure of the Permittee to satisfy the public notice requirements of WAC 173-226- 130(5), when applicable. The Director may require any discharger under this permit to apply for and obtain coverage under an individual permit or another more specific general permit. Permittees who have their coverage revoked for cause according to WAC 173-226-240 may request temporary coverage under this permit during the time an individual permit is being developed, provided the request is made within ninety (90) days from the time of revocation and is submitted along with a complete individual permit application form. G6. REPORTING A CAUSE FOR MODIFICATION The Permittee must submit a new application, or a supplement to the previous application, whenever a material change to the construction activity or in the quantity or type of discharge is anticipated which is not specifically authorized by this permit. This application must be submitted at least sixty (60) days prior to any proposed changes. Filing a request for a permit modification, revocation and reissuance, or termination, or a notification of planned changes or anticipated noncompliance does not relieve the Permittee of the duty to comply with the existing permit until it is modified or reissued. G7. COMPLIANCE WITH OTHER LAWS AND STATUTES Nothing in this permit will be construed as excusing the Permittee from compliance with any applicable federal, state, or local statutes, ordinances, or regulations. G8. DUTY TO REAPPLY The Permittee must apply for permit renewal at least 180 days prior to the specified expiration date of this permit. The Permittee must reapply using the electronic application form (NOT) available on Ecology's website. Permittees unable to submit electronically (for example, those who do not have an internet connection) must contact Ecology to request a waiver and obtain instructions on how to obtain a paper NOT. Department of Ecology Water Quality Program - Construction Stormwater PO Box 47696 Olympia, Washington 98504-7696 Cons ruc•iioll S7ormweller Genrrul Permit Page 40 Page 179 G9. TRANSFER OF GENERAL PERMIT COVERAGE Coverage under this general permit is automatically transferred to a new discharger, including operators of lots/parcels within a common plan of development or sale, if: A. A written agreement (Transfer of Coverage Form) between the current discharger (Permittee) and new discharger, signed by both parties and containing a specific date for transfer of permit responsibility, coverage, and liability (including any Administrative Orders associated with the Permit) is submitted to the Director; and B. The Director does not notify the current discharger and new discharger of the Director's intent to revoke coverage under the general permit. If this notice is not given, the transfer is effective on the date specified in the written agreement. When a current discharger (Permittee) transfers a portion of a permitted site, the current discharger must also submit an updated application form (NOI) to the Director indicating the remaining permitted acreage after the transfer. G10. REMOVED SUBSTANCES The Permittee must not re -suspend or reintroduce collected screenings, grit, solids, sludges, filter backwash, or other pollutants removed in the coarse of treatment or control of stormwater to the final effluent stream for discharge to state waters. Gl L DUTY TO PROVIDE INFORMATION The Permittee must submit to Ecology, within a reasonable time, all information that Ecology may request to determine whether cause exists for modifying, revoking and reissuing, or terminating this permit or to determine compliance with this permit. The Permittee must also submit to Ecology, upon request, copies of records required to be kept by this permit [40 CFR 122.41(h)]. G12. OTHER REQUIREMENTS OF 40 CFR All other requirements of 40 CFR 122.41 and 122.42 are incorporated in this permit by reference. G13. ADDITIONAL MONITORING Ecology may establish specific monitoring requirements in addition to those contained in this permit by administrative order or permit modification. G14. PENALTIES FOR VIOLATING PERMIT CONDITIONS Any person who is found guilty of willfully violating the terms and conditions of this permit shall be deemed guilty of a crime, and upon conviction thereof shall be punished by a fine of up to ten thousand dollars ($10,000) and costs of prosecution, or by imprisonment at the discretion of the court. Each day upon which a willful violation occurs may be deemed a separate and additional violation. Cu7ch-uelian Slormmruar General Permit Page 41 Page 180 Any person who violates the terms and conditions of a waste discharge permit shall incur, in addition to any other penalty as provided by law, a civil penalty in the amount of up to ten thousand dot {ors (S 10,000) for every such violation. Each and every such violation shall be a separate and distinct offense, and in case of a continuing violation, every day's continuance shall be deemed to be a separate and distinct violation. G15. UPSET Definition — "Upset" means an exceptional incident in which there is unintentional and temporary noncompliance with technology -based permit effluent limitations because of factors beyond the reasonable control of the Permittee. An upset does not include noncompliance to the extent caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventive maintenance, or careless or improper operation. An upset constitutes an affirmative defense to an action brought for noncompliance with such technology -based permit effluent limitations if the requirements of the following paragraph are met. A Permittee who wishes to establish the affirmative defense of upset must demonstrate, through properly signed, contemporaneous operating logs or other relevant evidence that: 1) an upset occurred and that the Permittee can identify the cause(s) of the upset; 2) the permitted facility was being properly operated at the time of the upset; 3) the Permittee submitted notice of the upset as required in Special Condition SS.F, and; 4) the Permittee complied with any remedial measures required under this permit. In any enforcement proceeding, the Permittee seeking to establish the occurrence of an upset has the burden of proof. G16. PROPERTY RIGHTS This permit does not convey any property rights of any sort, or any exclusive privilege. G17. DUTY TO COMPLY The Permittee must comply with all conditions of this permit. Any permit noncompliance constitutes a violation of the Clean Water Act and is grounds for enforcement action; for pen -nit termination, revocation and reissuance, or modification; or denial of a pen -nit renewal application. G18. TOXIC POLLUTANTS The Permittee must comply with effluent standards or prohibitions established under Section 307(a) of the Clean Water Act for toxic pollutants within the time provided in the regulations that establish those standards or prohibitions, even if this permit has not yet been modified to incorporate the requirement. i UgSll'IlL'llUl1 Sforlinvalur Gcncrui Pernrrr I';i,c 42 Page 181 G19. PENALTIES FOR TAMPERING The Clean Water Act provides that any person who falsifies, tampers with, or knowingly renders inaccurate any monitoring device or method required to be maintained under this permit shall, upon conviction, be punished by a fine of not more than $10,000 per violation, or by imprisonment for not more than two years per violation, or by both. If a conviction of a person is for a violation committed after a first conviction of such person under this condition, punishment shall be a fine of not more than $20,000 per day of violation, or imprisonment of not more than four (4) years, or both. G20. REPORTING PLANNED CHANGES The Permittee must, as soon as possible, give notice to Ecology of planned physical alterations, modifications or additions to the permitted construction activity. The Permittee should be aware that, depending on the nature and size of the changes to the original permit, a new public notice and other permit process requirements may be required. Changes in activities that require reporting to Ecology include those that will result in: A. The permitted facility being determined to be a new source pursuant to 40 CFR 122.29(b). B. A significant change in the nature or an increase in quantity of pollutants discharged, including but not limited to: for sites 5 acres or larger, a 20% or greater increase in acreage disturbed by construction activity. C. A change in or addition of surface water(s) receiving stormwater or non-stormwater from the construction activity. D. A change in the construction plans and/or activity that affects the Permittee's monitoring requirements in Special Condition S4. Following such notice, permit coverage may be modified, or revoked and reissued pursuant to 40 CFR 122.62(a) to specify and limit any pollutants not previously limited. Until such modification is effective, any new or increased discharge in excess of permit limits or not specifically authorized by this permit constitutes a violation. G21. REPORTING OTHER INFORMATION Where the Permittee becomes aware that it failed to submit any relevant facts in a permit application, or submitted incorrect information in a permit application or in any report to Ecology, it must promptly submit such facts or information. G22. REPORTING ANTICIPATED NON-COMPLIANCE The Permittee must give advance notice to Ecology by submission of a new application or supplement thereto at least forty-five (45) days prior to commencement of such discharges, of any facility expansions, production increases, or other planned changes, such as process modifications, in the permitted facility or activity which may result in noncompliance with permit limits or conditions. Any maintenance of facilities, which might necessitate C'onsinicrron Slorn water General Permit fla&e -43 Page 182 unavoidable interruption of operation and degradation of effluent quality, must be scheduled during non -critical water quality periods and carried out in a manner approved by Ecology. G23. REQUESTS TO BE EXCLUDED FROM COVERAGE UNDER THE PERMIT Any discharger authorized by this permit may request to be excluded from coverage under the general permit by applying for an individual permit. The discharger must submit to the Director an application as described in WAC 173-220-040 or WAC 173-2I6-070, whichever is applicable, with reasons supporting the request. These reasons will fully document how an individual permit will apply to the applicant in a way that the general permit cannot. Ecology may make specific requests for information to support the request. The Director will either issue an individual permit or deny the request with a statement explaining the reason for the denial. When an individual permit is issued to a discharger otherwise subject to the construction stormwater general permit, the applicability of the construction stormwater general permit to that Permittee is automatically terminated on the effective date of the individual permit. G24. APPEALS A. The terms and conditions of this general permit, as they apply to the appropriate class of dischargers, are subject to appeal by any person within 30 days of issuance of this general permit, in accordance with Chapter 43.21B RCW, and Chapter 173-226 WAC, B. The terms and conditions of this general permit, as they apply to an individual discharger. are appealable in accordance with Chapter 43.21 S RCW within 30 days of the effective date of coverage of that discharger. Consideration of an appeal of general permit coverage of an individual discharger is limited to the general permit's applicability or nonapplicability to that individual discharger. C. The appeal of general permit coverage of an individual discharger does not affect any other dischargers covered under this general permit. If the terms and conditions of this general permit are found to be inapplicable to any individual discharger(s), the matter shall be remanded to Ecology for consideration of issuance of an individual permit or permits. G25. SEVERABILITY The provisions of this permit are severable, and if any provision of this permit. or application of any provision of this permit to any circumstance, is held invalid, The application of such provision to other circumstances, and the remainder of this permit shall not be affected thereby. G26. BYPASS PROHIBITED A. Bypass Procedures Bypass, which is the intentional diversion of waste streams from any portion of a treatment facility, is prohibited for stormwater events below the design criteria for Page 183 stormwater management. Ecology may take enforcement action against a Permittee for bypass unless one of the following circumstances (1, 2, 3 or 4) is applicable. 1. Bypass of stormwater is consistent with the design criteria and part of an approved management practice in the applicable stormwater management manual. 2. Bypass for essential maintenance without the potential to cause violation of permit limits or conditions_ Bypass is authorized if it is for essential maintenance and does not have the potential to cause violations of limitations or other conditions of this permit, or adversely impact public health. 3. Bypass of stormwater is unavoidable, unanticipated, and results in noncompliance of this permit. This bypass is permitted only if: a. Bypass is unavoidable to prevent loss of life, personal injury, or severe property damage, "Severe property damage" means substantial physical damage to property, damage to the treatment facilities which would cause them to become inoperable, or substantial and permanent loss of natural resources which can reasonably be expected to occur in the absence of a bypass. b. There are no feasible alternatives to the bypass, such as the use of auxiliary treatment facilities, retention of untreated wastes, maintenance during normal periods of equipment downtime (but not if adequate backup equipment should have been installed in the exercise of reasonable engineeringjudgment to prevent a bypass which occurred during normal periods of equipment downtime or preventative maintenance), or transport of untreated wastes to another treatment facility. c. Ecology is properly notified of the bypass as required in Special Condition S5.F of this permit. 4. A planned action that would cause bypass of stormwater and has the potential to result in noncompliance of this permit during a storm event. The Permittee must notify Ecology at least thirty (30) days before the planned date of bypass. The notice must contain: a. A description of the bypass and its cause. b. An analysis of all known alternatives which would eliminate, reduce, or mitigate the need for bypassing. c. A cost-effectiveness analysis of alternatives including comparative resource damage assessment. d. The minimum and maximum duration of bypass under each alternative. e. A recommendation as to the preferred alternative for conducting the bypass. Conrnrucuon Slorom wer Gemrul Pernii! Pu,e - i Page 184 f. The projected date of bypass initiation. g. A statement of compliance with SEPA. h. A request for modification of water qualitystandards as provided for in WAC 173-201 A-] 10, if an excecdance of any water quality standard is anticipated. i. Steps taken or planned to reduce, eliminate, and prevent reoccurrence of the bypass. 5. For probable constniction bypasses, the need to bypass is to be identified as early in the planning process as passible. The analysis required above must be considered during preparation of the Stormwater Pal€ution Prevention Plan (SWPPP) and must be included to the extent practical, In cases where the probable need to bypass is determined early, continued analysis is necessary up to and including the construction period in an effort to minimize or eliminate the bypass. Ecology will consider the following before issuing an administrative order for this type bypass: a. If the bypass is necessary to perform construction or maintenance -related activities essential to meet the requirements of this permit. b. If there are feasible alternatives to bypass, such as the use of auxiliary treatment facilities, retention of untreated wastes, stopping production, maintenance during normal periods of equipment down time, or transport of untreated wastes to another treatment facility. c. If the bypass is planned and scheduled to minimize adverse effects on the public and the environment. After consideration of the above and the adverse effects of the proposed bypass and any other relevant factors, Ecology will approve, conditionally approve, or deny the request. The public must be notified and given an opportunity to comment on bypass incidents of significant duration, to the extent feasible. Approval of a request to bypass will be by administrative order issued by Ecology under RCW 90.48.120. B. Duty to Mitigate The Permittee is required to take all reasonable steps to minimize or prevent any discharge or sludge use or disposal in violation of this permit that has a reasonable likelihood of adversely affecting human health or the environment. C o17.s-truciioi1 Stoomi,ater GeJ70-ul Pel-Mit Page 46 Page 185 APPENDIX A — DEFINITIONS AKART is an acronym for "all known, available, and reasonable methods of prevention, control, and treatment." AKART represents the most current methodology that can be reasonably required for preventing, controlling, or abating the pollutants and controlling pollution associated with a discharge. Applicable TMDL means a TMDL for turbidity, fine sediment, high pH, or phosphorus, which was completed and approved by EPA before January 1, 2016, or before the date the operator's complete permit application is received by Ecology, whichever is later. Applicant means an operator seeking coverage under this permit. Benchmark means a pollutant concentration used as a permit threshold, below which a pollutant is considered unlikely to cause a water quality violation, and above which it may. When pollutant concentrations exceed benchmarks, corrective action requirements take effect. Benchmark values are not water quality standards and are not numeric effluent limitations; they are indicator values. Best Management Practices (BMPs) means schedules of activities, prohibitions of practices, maintenance procedures, and other physical, structural and/or managerial practices to prevent or reduce the pollution of waters of the State. BMPs include treatment systems, operating procedures, and practices to control: stormwater associated with construction activity, spillage or leaks, sludge or waste disposal, or drainage from raw material storage. Buffer means an area designated by a local jurisdiction that is contiguous to and intended to protect a sensitive area. Bypass means the intentional diversion of waste streams from any portion of a treatment facility. Calendar Day A period of 24 consecutive hours starting at 12:00 midnight and ending the following 12:00 midnight. Calendar Week (same as Week) means a period of seven consecutive days starting at 12:01 a.m. (0:01 hours) on Sunday. Certified Erosion and Sediment Control Lead (CESCL) means a person who has current certification through an approved erosion and sediment control training program that meets the minimum training standards established by Ecology (see BMP C 160 in the SWMM). Chemical Treatment means the addition of chemicals to slorrmvater and/or authorized non- stormwater prior to filtration and discharge to surface waters. Clean Water Act (CWA) means the Federal Water Pollution Control Act enacted by Public Law 92-500, as amended by Public Laws 95-217, 95-576, 96-483, and 97-117; USC 1251 et seq. Combined Sewer means a sewer which has been designed to serve as a sanitary sewer and a storm sewer, and into which inflow is allowed by local ordinance. C'unslrrrroon Stornnruter Generui Pernrrr P -ge 47 Page 186 Common Plan of Development or Sale means a site where multiple separate and distinct construction activities may be taking place at different times on different schedules and/or by different contractors, but still under a single plan. Examples include: l) phased projects and projects with multiple filings or lots, even if the separate phases or filings/lots will be constructed under separate contract or by separate owners (e.g., a development where lots are sold to separate builders); 2) a development plan that may be phased over multiple years, but is still under a consistent plan for long-term development; 3) projects in a contiguous area that may be unrelated but still under the same contract, such as construction of a building extension and a new parking lot at the same facility; and 4) linear projects such as roads, pipelines, or utilities. If the project is part of a common plan of development or sale, the disturbed area of the entire plan must be used in determining permit requirements. Composite Sample means a mixture of grab samples collected at the same sampling point at different times, formed either by continuous sampling or by mixing discrete samples. May be "time -composite" (collected at constant time intervals) or "flow -proportional" (collected either as a constant sample volume at time intervals proportional to stream flow, or collected by increasing the volume of each aliquot as the flow increases while maintaining a constant time interval between the aliquots. Concrete Wastewater means any water used in the production, pouring and/or clean-up of concrete or concrete products, and any water used to cut, grind, wash, or otherwise modify concrete or concrete products. Examples include water used for or resulting from concrete truck/mixer/pumper/tool/chute rinsing or washing, concrete saw cutting and surfacing (sawing, coring, grinding, roughening, hydro -demolition, bridge and road surfacing). When .stormtivater comingles with concrete wastewater, the resulting water is considered concrete wastewater and must be managed to prevent discharge to waters 9f the State, including ground water. Construction Activity means land disturbing operations including clearing, grading or excavation which disturbs the surface of the land. Such activities may include road construction, construction of residential houses, office buildings, or industrial buildings, site preparation, soil compaction, movement and stockpiling of topsoils, and demolition activity. Contaminant means any hazardous substance that does not occur naturally or occurs at greater than natural background levels. See definition of "hazardous substance" and WAC 173-340-200. Contaminated Groundwater means groundwater which contains contaminants, pollutants, or hazardous substances that do not occur naturally or occur at levels greater than natural background. Contaminated Soil means soil which contains contaminants, pollutants, or hazardous substances that do not occur naturally or occur at levels greater than natural background. Demonstrably Equivalent means that the technical basis for the selection of all stormwater BMPs is documented within a SWPPP, including: 1. The method and reasons for choosing the stormwater BM -Ps selected. Construction Stormwarcr General Permir N,e 48 Page 187 2. The pollutant removal performance expected from the BMPs selected. 3. The technical basis supporting the performance claims for the BMPs selected, including any available data concerning field performance of the BMPs selected. 4. An assessment of how the selected BMPs will comply with state water quality standards. 5. An assessment of how the selected BMPs will satisfy both applicable federal technology - based treatment requirements and state requirements to use all known, available, and reasonable methods of prevention, control, and treatment (AKART). Department means the Washington State Department of Ecology. Detention means the temporary storage of stormwater to improve quality and/or to reduce the mass flow rate of discharge. Dewatering means the act of pumping ground water or stormwater away from an active construction site. Director means the Director of the Washington State Department of Ecology or his/her authorized representative. Discharger means an owner or operator of any facility or activity subject to regulation under Chapter 90.48 RCW or the Federal Clean Water Act. Domestic Wastewater means water carrying human wastes, including kitchen, bath, and laundry wastes from residences, buildings, industrial establishments, or other places, together with such ground water infiltration or surface waters as may be present. Ecology means the Washington State Department of Ecology. Engineered Soils means the use of soil amendments including, but not limited, to Pori Lind cement treated base (CTB). cement kiln dust (CKD), or fly ash to achieve certain desirable soil characteristics. Equivalent BMPs means operational, source control, treatment, or innovative BMPs which result in equal or better quality of stormwater discharge to surf lee water or to ground water than BMPs selected from the SWMM. Erosion means the wearing away of the land surface by running water, wind, ice, or other geological agents, including such processes as gravitational creep. Erosion and Sediment Control BMPs means BMPs intended to prevent erosion and sedimentation, such as preserving natural vegetation, seeding, mulching and matting, plastic covering, filter fences, sediment traps, and ponds. Erosion and sediment control BMPs are synonymous with stabilization and structural BMPs. Federal Operator is an entity that meets the definition of "Operator" in this permit and is either any department, agency or instrumentality of the executive, legislative, and judicial branches of Ccm.'Irucliun Siornw-werGeneralPernnil Page 49 Page 188 the Federal government of the United States, or another entity, such as a private contractor, performing construction activity for any such department, agency, or instrumentality. Final Stabilization (same as fully stabilized or full stabilization) means the establishment of a permanent vegetative cover, or equivalent permanent stabilization measures (examples of permanent non -vegetative stabilization methods include, but are not limited to riprap, gabions or geotextiles) which prevents erosion. Ground Water means water in a saturated zone or stratum beneath the land surface or a surface waterbody. Hazardous Substance means any dangerous or extremely hazardous waste as defined in RCW 70.105.010 (5) and (6), or any dangerous or extremely dangerous waste as designated by rule under chapter 70.105 RCW; any hazardous substance as defined in RCW 70.105.010(10) or any hazardous substance as defined by rule under chapter 70.105 RCW; any substance that, on the effective date of this section, is a hazardous substance under section 101(14) of the federal cleanup law, 42 U.S.C., Sec. 9601(14); petroleum or petroleum products; and any substance or category of substances, including solid waste decomposition products, determined by the director by rule to present a threat to human health or the environment if released into the environment. The term hazardous substance does not include any of the following when contained in an underground storage tank from which there is not a release; crude oil or any fraction thereof or petroleum, if the tank is in compliance with all applicable federal, state, and local law. Injection Well means a well that is used for the subsurface emplacement of fluids. (See Well.) Jurisdiction means a political unit such as a city, town or county; incorporated for local self- government. National Pollutant Discharge Elimination System (NPDES) means the national program for issuing, modifying, revoking and reissuing, terminating, monitoring, and enforcing permits, and imposing and enforcing pretreatment requirements, under sections 307, 402, 318, and 405 of the Federal Clean Water Act, for the discharge of pollutants to surface waters of the State from point sources. These permits are referred to as NPDES permits and, in Washington State, are administered by the Washington State Department of Ecology, Notice of Intent (NOI) means the application for, or a request for coverage under this general permit pursuant to WAC 173-226-200. Notice of Termination (NOT) means a request for termination of coverage under this general permit as specified by Special Condition S10 of this permit. Operator means any party associated with a construction project that meets either of the following two criteria: The party has operational control over construction plans and specifications, including the ability to make modifications to those plans and specifications; or Cmutrurlion Slonnwaier General Permil P ue �O Page 189 • The party has day-to-day operational control of those activities at a project that are necessary to ensure cornpIiance with a SWPPP for the site or other per mit conditions (e.g., they are authorized to direct workers at a site to carry out activities required by the SWPPP or comply with other permit conditions). Permittee means individual or entity that receives notice of coverage under this general permit. pH means a liquid's measure of acidity or alkalinity. A pH of 7 is defined as neutral. Large variations above or below this value are considered harmful to most aquatic life. pH Monitoring Period means the time period in which the pH of stormwater runoff from a site must be tested a minimum of once every seven days to determine if stonmwater pH is between 6.5 and 8.5. Point Source means any discernible, confined, and discrete conveyance, including but not limited to, any pipe, ditch, channel. tunnel, conduit, well, discrete fissure, and container from which pollutants are or may be discharged to surface waters of the State. This term sloes not include return flows from irrigated agriculture. (See Fact Sheet For further explanation.) Pollutant means dredged spoil, solid waste, incinerator residue, filter backwash, sewage, garbage, domestic sewage sludge (biosolids), munitions, chemical wastes, biological materials, radioactive materials, heat, wrecked or discarded cquipmenE, rock, sand, cellar dirt. and industrial, municipal, and agricultural waste. This term does not include sewage from vessels within the meaning of section 312 of the CWA, nor does it include dredged or fill material discharged in accordance with a permit issued under section 404 of the CWA. Pollution means contamination or other alteration of the physical, chemical, or biological properties of waters of the State; including change in temperature, taste, color, turbidity, or odor of the waters; or such discharge of any liquid, gaseous, solid. radioactive or other substance into any tiraters of the Stare as will or is likely to create a nuisauce or render such waters harmful, detrimental or injurious to the public health. safety or welfare; or to domestic, commercial, industrial, agricultural, recreational. or other legitimate bencficial uses; or to livestock, wild animals, birds, fish or other aquatic life. Process Wastewater means any water which, during manufacturing or processing, comes into direct contact with or results from the production or use of any raw material, intermediate product, finished product, byproduct, or waste product. If stormwater commingles with process wastewater, the commningled water is considered process wastewater. Receiving Water means the watcrbody at the point of discharge. If the discharge is to a .storm .seuwer.$)arrem, either surface or subsurface, the receiving water is the watt rbody to which the storm system discharges. Systems designed primarily for other purposes such as for ground water drainage, redirecting stream natural flows, or for conveyance of irrigation water/return flows that coincidentally convey stormwater are considered the receiving water. Cunsintoion Stornnrater General Permit Page 4; 1 Page 190 Representative means a storm ivatcr or wastewater sample which represents the flow and characteristics of the discharge. Representative samples may be a grab sample, a time - proportionate Composite sample, or a flow proportionate sample. Ecology's Construction Stormwater Monitoring Manual provides guidance on representative sampling. Responsible Corporate Officer for the purpose of signatory authority means: (il a president, secretary, treasurer, or vice-president of the corporation in charge of a principal business function, or any other person who performs similar policy- or decision -►Waking functions for the corporation, or (ii) the manager of one or more manufacturing. production, or operating facilities. provided, the manager is authorized to make management decisions which govern the operation of the regulated facility including having the explicit or implicit duty of snaking major capital investment recommendations, and initiating and directing other comprehensive measures to assure long term environmental compliance with environmental laws and regulations; the manager can ensure that the necessary systems are established or actions taken to gather complete and accurate information for permit application requirements; and where authority to sign documents has been assigned or delegated to the manager in accordance with corporate procedures (40 CFR 122.22), Sanitary Sewer means a sewer which is designed to convey domestic wastewater. Sediment means the fragmented material that originates from the weathering and erosion of rocks or unconsolidated deposits, and is transported by, suspended in, or deposited by water. Sedimentation means the depositing or formation of sediment. Sensitive Area means a waterbody, wetland, stream, aquifer recharge area, or channel migration zone. SEPA (State Environmental Policy Act) means the Washington State Law, RCW 43.21 C.020, intended to prevent or eliminate damage to the environment. Significant Amount means an amount of a polinrant in a discharge that is amenable to available and reasonable methods of prevention or treatment; or an amount of a pollilluut that has a reasonable potential to cause a violation of surface or ground water quality or sediment management standards. Significant Concrete Work means greater than 1000 cubic yards poured concrete used over the life of a project. Significant Contributor of Pollutants means a facility determined by Ecology to be a contributor of a significant amount(s) of a polkrlant(s) to waters of the State of Washington. Site means the land or water area where any "facility or activity" is physically located or conducted. Source Control BMPs means physical, structural or mechanical devices or facilities that are intended to prevent pollutants from entering storrrlwater. A few examples of source control CUnsInIcliol7 slornnvuler General Permit Page Page 191 BMPs are erosion control practices, maintenance of stormwater facilities, constructing roofs over storage and working areas, and directing wash water and similar discharges to the .sanitary sewer or a dead end sump. Stabilization means the application of appropriate BMPs to prevent the erosion of soils, such as, temporary and permanent seeding, vegetative covers, mulching and matting, plastic covering and sodding. See also the definition of Erosion and Sediment Control BMPs. Storm Drain means any drain which drains directly into a storm sewer system, usually found along roadways or in parking lots. Storm Sewer System means a means a conveyance, or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, manmade channels, or storm drains designed or used for collecting or conveying storrwater. This does not include systems which are part of a combined sewer or Publicly Owned Treatment Works (POTW) as defined at 40 CFR 122.2. Stormwater means that portion of precipitation that does not naturally percolate into the ground or evaporate, but flows via overland flow, interflow, pipes, and other features of a stormwater drainage system into a defined surface waterbody, or a constructed infiltration facility. Stormwater Management Manual (SWMM) or Manual means the technical Manual published by Ecology for use by local governments that contain descriptions of and design criteria for BMPs to prevent, control, or treat pollutants in stormwater. Stormwater Pollution Prevention Plan (SWPPP) means a documented plan to implement measures to identify, prevent, and control the contamination of point source discharges of stormwater. Surface Waters of the State includes lakes, rivers, ponds, streams, inland waters, salt waters, and all other surface waters and water courses within the jurisdiction of the State of Washington. Temporary Stabilization means the exposed ground surface has been covered with appropriate materials to provide temporary stabilization of the surface from water or wind erosion. Materials include, but are not limited to, mulch, riprap, erosion control mats or blankets and temporary cover crops. Seeding alone is not considered stabilization. Temporary stabilization is not a substitute for the more permanent "final stabilization." Total Maximum Daily Load (TMDL) means a calculation of the maximum amount of a pollutant that a waterbody can receive and still meet state water quality standards. Percentages of the total maximum daily load are allocated to the various pollutant sources. A TMDL is the sum of the allowable loads of a single pollutant from all contributing point and nonpoint sources. The TMDL calculations must include a "margin of safety" to ensure that the waterbody can be protected in case there are unforeseen events or unknown sources of the pollutant. The calculation must also account for seasonable variation in water quality. C'onsiruetion S7ormwater General Permit P tgc i3 Page 192 Transfer of Coverage (TOC) means a request for transfer of coverage under this general permit as specified by General Condition G9 of this permit. Treatment BMPs means BMPs that are intended to remove pollutants from stormwater. A few examples of treatment BMPs are detention ponds, oil/water separators, biofiltration, and constructed wetlands. Transparency means a measurement of water clarity in centimeters (cm), using a 60 cm transparency tube. The transparency tube is used to estimate the relative clarity or transparency of water by noting the depth at which a black and white Secchi disc becomes visible when water is released from a value in the bottom of the tube. A transparency tube is sometimes referred to as a "turbidity tube." Turbidity means the clarity of water expressed as nephelometric turbidity units (NTUs) and measured with a calibrated turbidimeter. Uncontaminated means free from any contaminant. See definition of "contaminant' and WAC 173-340-200. Waste Load Allocation (WLA) means the portion of a receiving water's loading capacity that is allocated to one of its existing or future point sources of pollution. WLAs constitute a type of water quality based effluent limitation (40 CFR 130.2[h]). Water -only Based Shaft Drilling is a shaft drilling process that uses water only and no additives are involved in the drilling of shafts for construction of building, road, or bridge foundations. Water quality means the chemical, physical, and biological characteristics of water, usually with respect to its suitability for a particular purpose. Waters of the State includes those waters as defined as "waters of the United States" in 40 CFR Subpart 122.2 within the geographic boundaries of Washington State and "waters of the State" as defined in Chapter 90.48 RCW, which include lakes, rivers, ponds, streams, inland waters, underground waters, salt waters, and all other surface waters and water courses within the jurisdiction of the state of Washington. Well means a bored, drilled or driven shaft, or dug hole whose depth is greater than the largest surface dimension. (Sec Injection well.) Wheel Wash Wastewater means any water used in, or resulting from the operation of, a tire bath or wheel wash (BMP C 106: Wheel Wash), or other structure or practice that uses water to physically remove mud and debris from vehicles [caving a construction site and prevent track - out onto roads. When stornm-ater comingles with wheel wash wastewater, the resulting water is considered wheel wash wastewater and must be managed according to Special Condition S9.D.9. Conslrurtion stornnruter Gcmrul Permit Pagc 54 Page 193 APPENDIX B — ACRONYMS AKART All Known, Available, and Reasonable Methods of Prevention, Control, and Treatment BMP Best Management Practice CESCL Certified Erosion and Sediment Control Lead CFR Code of Federal Regulations CKD Cement Kiln Dust CM Centimeters CTB Cement -Treated Base CWA Clean Water Act DMR Discharge Monitoring Report EPA Environmental Protection Agency ERTS Environmental Report Tracking System ESC Erosion and Sediment Control FR Federal Register LID Low Impact Development NOI Notice of Intent NOT Notice of Termination NPDES National Pollutant Discharge Elimination System NTU Nephelometric Turbidity Unit RCW Revised Code of Washington SEPA State Environmental Policy Act SWMM Stormwater Management Manual SWPPP Stormwater Pollution Prevention Plan TMDL Total Maximum Daily Load UIC Underground Injection Control USC United States Code USEPA United States Environmental Protection Agency WAC Washington Administrative Code WQ Water Quality WWHM Western Washington Hydrology Model C'onsirucrkrn Sturnnrarer General Permit Page Page 194 F. 303(d) List Waterbodies / TMDL Waterbodies Information N/A G. Contaminated Site Information N/A H. Engineering Calculations N/A Page 195