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20-104332-UP-Wetland Buffer Enhancement Plan-11-06-2020-V2Critical Areas Report AFICHUK SINGLE-FAMILY RESISDENCE Prepared for: City of Federal Way Community Development Department 33325 81" Ave S Federal Way, WA 98003 Prepared on behalf of (applicant): Stanislav Afichuk 37237 421d Ave S Auburn, WA 98001 FEDERAL WAY October 2020 WATERSHED �� COMPANY Title -page image: View of Puget Sound from subject property. The information contained in this report is based on the application of technical guidelines currently accepted as the best available science and in conjunction with the manuals and criteria outlined in the methods section. All discussions, conclusions and recommendations reflect the best professional judgment of the author(s) and are based upon information available at the time the study was conducted. All work was completed within the constraints of budget, scope, and timing. The findings of this report are subject to verification and agreement by the appropriate local, state and federal regulatory authorities. No other warranty, expressed or implied, is made. 2 THE WATERSHED COMPANY 750 Sixth Street South Kirkland, WA 98033 425.822.5242 Reference Number: 191123 425.827.81 36 Contact: Grace Brennan — Ecologist watershedco. com Table of Contents 1 Introduction................................................................................................................. 5 2 Existing Conditions...................................................................................................... 5 2.1 Location............................................................................................................. 5 2.2 Site Description..................................................................................................6 2.3 Environmental Setting.......................................................................................7 2.4 Critical Areas...................................................................................................... 7 2.4.1 Stream................................................................................................... 7 2.4.2 Wetland.................................................................................................8 2.4.3 Wetland and Stream Buffer................................................................10 2.4.4 Erosion Hazard Areas.......................................................................... 10 3 Proposed Project....................................................................................................... 11 3.1 Overview..........................................................................................................11 3.2 Local Regulations............................................................................................. 11 3.2.1 SEPA Categorical Exemption............................................................... 11 3.2.2 Wetland and Stream Buffer................................................................ 12 3.2.3 Erosion Hazard Areas..........................................................................12 3.2.4 Development Standards - Trees.........................................................12 3.2.5 Critical Areas Mitigation Sequencing..................................................13 3.3 Impact Analysis & Local Regulations...............................................................13 3.4 Functional Lift Analysis.................................................................................... 14 4 Reasonable Use Exception........................................................................................ 15 4.1 Addressing KCC 11.06.090: Reasonable Use Provision...................................15 5 Conclusion.................................................................................................................17 Appendix A RUE Mitigation Plan Appendix B Wetland and Stream Delineation Report Appendix C Tree Inventory Report Appendix D Geotechnical Report List of Figures Figure 1. Vicinity and study area map, subject parcel in purple outline ...................................... 6 Figure 1. End of Stream A............................................................... Error! Bookmark not defined. Figure 2. Wetland A, looking to the eastern slope ........................ Error! Bookmark not defined. List of Tables Table 1. Wetland A summary table .............................................. Error! Bookmark not defined. Table 2. Tree impact and removal summary............................................................................. 12 I Introduction The purpose of this report is to document compliance with the requirements of the City of Federal Way Revised Code (FWRC) in the development of a single-family residence located off S 293rd Street in the City of Federal Way, WA (parcel no. 7202500080). Specifically, this report provides an analysis of the proposed work relative to the requirements of FWRC Chapter 19.145 (Environmentally Critical Areas), and an analysis evaluating the effects of the proposed project on wetland and stream functions. The site is highly encumbered by critical areas that would deny all reasonable use of the site, therefore, a reasonable use exception pursuant to FWC 19.145.090 is sought. 2 Existing Conditions 2.1 Location The subject parcel, parcel #7202500080, is located at 1XX S 293rd Street and is located off of S 293rd Street within the City of Federal Way jurisdiction (Figure 1). It is situated within Section 05 of Township 21 North, Range 04 East of the Public Land Survey System. a J a t � S 27S1h N .. sc r u Redondo � a aZc ='• ;J° a s • - r L K - _ 4 •r S17"ImiEk ti[dIT, Lake �3 1 t If ..,, 1 $?92nd St 3 284th 51 I� S 2E! v ' 4 v Ap ��$ f1.4 ' r ; _�tlelaidi' t �I. 2 w Elayc= o° _ b Rill Park d'.-.e 9 &iirror Lake SW 312th St SW Mirror 3i.2th St z� 1 Lakota Lake French Park L,k�v Figure 1. Vicinity and study area map, subject parcel in purple outline. 2.2 Site Description The subject parcel is 0.43 acres in size and topography is characterized by a ravine that runs northwest from the southeast corner of the of the property, sloping steeply downhill generally towards Puget Sound. The property is entirely undeveloped and abuts a section of road frontage at S 293td Street in the southwest. The site contains a mixed deciduous conifer overstory with a robust native shrub understory for a majority of the site. A terrace area in the southeast corner of the site is an exception; this area is primarily vegetated by reed canarygrass and Himalayan blackberry. Native species dominating the site consist of a red alder canopy with an Osoberry, salmonberry, and sword fern understory. One small stream, Stream A, runs along the center of the subject property in the ravine. One wetland unit, Wetland A, follows Stream A, stretching up the ravine walls in seep areas in some places. 0 2.3 Environmental Setting The subject parcel is located in the within the Lower Puget Sound - DM/Federal Way sub basin of the Duwamish - Green Water Resource Inventory Area (WRIA 9). It is situated in City of Federal Way. Surrounding land use is primarily single-family residential, although much of the land southeast of the subject property is undeveloped. Parcels immediately north, south, and west of the subject property are developed. The parcel immediately east of the subject area is the Crown Point Open Area and is owned by the City of Federal Way as a protected greenspace. The area is more broadly characterized as Puget Sound Douglas -Fir Vegetation Zone, within the Puget Trough Ecoregion. At a landscape scale, the region is heavily developed by high -density residential; however, some habitat connectivity is provided through Crown Point Open Area and other adjoining greenspace. Wetland A, Stream A and the undeveloped subject property are part of this larger wildlife corridor. 2.4 Critical Areas Wetlands and streams were delineated in by The Watershed Company in the separate report Afichuk Property, Stream Delineation Report (2020) (Appendix B). A summary of findings is provided below. 2.4.1 Stream One Stream, Stream A, was identified within the subject property. Stream A is a small stream fed primarily through groundwater seeps, averaging three to four feet in width and flowing along a steep gradient. Stream substrate is dominated by muck with intermittent sections of cobble. A portion of the stream flow is conveyed in a black 12-inch HDPE pipe that extends to the northern property line. This pipe does not carry all flow, and an active stream channel persists adjacent to and beneath the piped section. Stream flow enters a catch basin and drain at the northern property line. Stream A is seasonally flowing and originates just south of the subject property and ends in the northern section of the subject property. The stream flows along a slope of greater than twenty percent. Stream A is not documented as a fish bearing stream, and due to its steep flow gradient and seasonal nature, it does not contain suitable fish habitat. 7 Figure 2. End of Stream A. 2.4.2 Wetland Wetland A runs along the margins of Stream A and extends upslope of Stream A in some places. Wetland A is associated with Stream A, but greater than ninety percent of the wetland area is classified as a slope hydrogeomorphic class. Groundwater seeps throughout the wetland are Wetland A's main source of hydrology. Overbank flooding from Stream A is a secondary source of hydrology for this wetland. Figure 3. Wetland A, looking to the eastern slope. Wetland A is characterized by scrub -shrub and emergent plant communities. Vegetation within the wetland is generally dense and robust, with moderate diversity and complexity. Scrub - shrub areas are dominated by salmonberry (Rubus spectabilis), with a lady fern understory (Athyrium filix femina). Emergent areas are dominated by lady fern and piggy -back plant (Tolmiea menziesii). Minimal invasive species were present within in the wetland area; only a few small patches of Himalayan blackberry (Rubus arundinacea) were identified during site visits. A summary of the Wetland A is included in Table 1, below. Table 1. Wetland A summary. Wetland Name I HGM Classification Category Wetland A j Slope, riverine I Category III Habitat Score A Buffer (ft) 150 0 2.4.3 Wetland and Stream Buffer According to the code, Wetland A is rated as a Category III wetland with a habitat score of 6 points, and therefore requires a 150-foot buffer (FWRC 19.145.420[2]). Stream buffers are determined based on the stream type classification. Stream A meets the criteria of a Type Ns water. Type Ns streams require a buffer of 35 feet (FWRC 19.145.270[1]). Federal Way requires a 5-foot building setback from the edges of all critical area buffers (FWRC 19.145.160). Building setbacks may contain landscaping, building overhangs, and fences or railings six feet or less in height. Wetland and stream buffers encompass the entirety of the buildable area of the property, in the areas west of the ravine. The buffer is primarily vegetated by a healthy native plant community and provides generally well -functioning habitat areas. These areas are dominated by a canopy of red alder and big leaf maple, with an understory of Osoberry, salmonberry, and sword fern. There are some pockets of degraded buffer that are dominated by invasive species such as reed canarygrass, Himalayan blackberry and English holly. The primary degraded area has been cited as the location for site development. 2.4.4 Erosion Hazard Areas The entire property has been identified as an erosion hazard area (King County iMap). As discussed in the Geologic Hazard Assessment (GeoResources, 2020) (Appendix D), site soils are mapped as AkF, which have a severe erosion hazard when exposed. 2.4.5 Landslide Hazard Areas As discussed in the Geologic Hazard Assessment (GeoResources, 2020), the site meets some, but not all Landslide Hazard Area criteria outlined in FWRC 19.05.070.G(2), including containing slopes that are steeper than 15 percent. Based on field observations and literature review, GeoResources maintains that the site does not meet technical criteria of a landslide hazard area. Additionally, in their opinion, the proposed site development will mitigate the risk associated with a steep slope site through grading of surficial disturbed/weathered soils and drainage and erosion control, therefore, no additional buffer other than the stream buffer is necessary to protect the on -site slope and adjacent development. 10 Proposed Project 3.1 Overview The parcel was acquired by the applicant in 2019 and is currently undeveloped and vacant. The proposed project includes the construction of a single-family residence on the undeveloped parcel, along with associated underground utilities, and an access driveway from 293rd Street S. The new two-story residence will total approximately 2,369 square feet in total building footprint, including the garage and eaves. The combined wetland/stream buffer encumbers the entirety of the property. Therefore, a critical areas reasonable use exception is sought because a reasonably sized, single-family house with associated access and utilities will not be possible with strict adherence to the City's environmentally critical area regulations, even when utilizing the maximum 25 percent reduced wetland and stream buffers currently allowed under FWRC 19.145. The proposed residence will be located in the southwest corner of the property, within the wetland buffer. Compensation for impacts to the wetland buffer will include enhancement of portions of Wetland A's buffer. Mitigation planting areas (Appendix A) will focus on the portion of the lot nearest the development to provide the greatest amount of functional lift. Proposed enhancement includes the removal of invasive species throughout the mitigation area and installation of native trees, shrubs, and herbaceous vegetation. Some portions of the proposed mitigation area have limited opportunity for enhancement through invasive species removal and planting a new native plant community; these areas will be planted with a later successional plant community to replace the alder canopy that currently exists onsite. The mitigation area totals 13,465 square feet total, with 2,230 square feet of buffer restoration and 11,235 square feet of understory infill of a later successional plant community. Overall permanent impacts will be mitigated at a greater than 3:1 ratio, with a less than 1:1 ratio for mitigation enhancement and a 2.5:1 ratio for those areas being planted with later successional species. 3.2 Local Regulations 3.2.1 SEPA Categorical Exemption The project proposal is categorically exempt from a threshold determination per FWRC 14.15 and WAC 197-11, as it proposes one dwelling unit and does not propose direct impacts to lands covered by water. 11 3.2.2 Wetland and Stream Buffer All buffer alterations are subject to the avoidance, minimization, and mitigation requirements of FWRC 19.145.130. A mitigation sequencing narrative is provided in Section 3.2.5 below. The buffer alterations must also comply with the specific development standards for each critical area (FWRC 19.145.440; wetlands and FWRC 19.145.330; streams). Further, additional mitigation requirements specific to wetlands and aquatic areas also apply, including the requirement to provide equivalent or greater critical area functions, an adequate mitigation ratio to compensate for adverse impacts, and adherence to a comprehensive mitigation monitoring program. 3.2.3 Erosion Hazard Areas Due to this project's presence within an erosion hazard area, FWRC 16.145.250 requires that a report that demonstrates that the improvement will not increase surface water discharge, decrease slope stability on adjacent properties, and that the improvement will not adversely impact other critical areas is required. See the attached Geologic Hazard Assessment (GeoResources, 2020) report for more details. 3.2.4 Development Standards - Trees As discussed in the Arborist Report prepared by The Watershed Company in August 2020 (Appendix C), the subject property contains 23 significant trees. Of these trees, two will be removed and six trees are expected to receive impacts to their critical root zones (Table 2). Per FWRC 19.120.130, Trees #1308 and #1309, which are to be removed, are exempt due to their poor condition. Therefore, no trees designated for removal are subject to tree protection standards. Due to high overall tree count on the forested parcel, the existing tree unit credits currently far exceed the minimum standard of 11 tree units, with 72.5 tree credits available. All trees and vegetation proposed for retention shall be protected during construction according to standards outlined in FWRC 19.120.160. Table 2. Tree impact and removal summary. Tag # Tree Name Combined Height Radius Condition Tree Proposed DBH (In) (Ft) (Ft) Units for Removal 1301 Alnus rubra (Red 11.5 60 15 2 1.5 NO Alder) 1302 Alnus rubra (Red 10.8 60 12 2 1.5 NO Alder) 12 1303 Alnus rubra (Red 13.6 NO Alder) 60 15 2 2.0 1305 Alnus rubra (Red 9.8 NO Alder) 60 10 4 n/a 1306 Alnus rubra (Red 11.6 NO Alder) 60 15 3 1.5 1307 Alnus rubra (Red 11.8 NO Alder) 65 15 2 1.5 1308 Alnus rubra (Red 10.7 Alder) 25 5 4 n/a YES 1309 Alnus rubra (Red 8.9 Alder) 50 12 4 n/a YES 3.2.5 Critical Areas Mitigation Sequencing Avoidance: Site improvements have avoided direct impacts to critical areas. The development area boundary is proposed at least 37 feet away from all critical areas. The site plan has been developed in order to retain the maximum number of trees of significance. Minimize: The project minimizes impacts to critical area buffers by limiting the number of trees impacted and locating the residence in the most disturbed area of the property near the access road, minimizing impacts to native vegetation and driveway size. Mitigate: The impacts will be mitigated on site by installation of dense, native vegetation in areas suitable for buffer restoration, and understory infill of later successional plants in those areas already vegetated with a dense native plant community. The proposed mitigation area currently provides a generally high level of ecological function overall, and the proposed plan aims to maintain, and improve upon, that high level of function. Monitor: The mitigation site will be maintained and monitored for a minimum of five years to ensure that it meets the designated performance standards. 3.3 Impact Analysis & Local Regulations The project proposes two impact types: impervious area and yard/setback area. These impacts are discussed below. In addition, tree removal and replacement discussion are also provided. House Construction The house's 2,369 square foot footprint is situated in order to reduce overall impacts to critical areas. The proposed location of the house is in the most disturbed area of the property, on the terrace located in the southwest corner of the subject property that is currently dominated by 13 reed canarygrass and Himalayan blackberry. A majority of the impacts from the house will be confined to this area; however, areas of dense native vegetation will be impacted through the construction of the proposed single-family home. The proposed plan will result in the loss of wetland buffer functions, such as loss of habitat and water quality function. The proposed mitigation plan looks to mitigate some of these impacts through adding habitat structure and dense native vegetation, that will offset some of the functions lost through house construction. Additionally, house construction will follow best management practices outlined in the attached arborist and geotechnical report in order to minimize impacts during and after construction. These include, but are not limited to, identifying no -disturbance zones for trees, installing a silt fence along the downslope and side slopes of the active construction area, and utilizing drainage and other erosion controls. Driveway The driveway is oriented to meet those requirements outlined in FWRC 19.120.110, while reducing the distance of the house to the critical areas. FWRC 19.120.110 requires a minimum twenty -foot length parking area; the planned driveway offers 26 feet in parking length in order to gain access to the odd -shaped lot. Front Yard The front yard is oriented to the southwest of the proposed residence, away from critical areas in order to reduce impacts. 3.4 Functional Lift Analysis Through the mitigation plan, function lift will be provided site wide. Areas along the southwestern edge of the subject parcel and directly north of Wetland A will be provided with the most functional lift: these areas are currently either vegetated with invasive species which will be removed during mitigation, or sparsely vegetated. Through planting of dense native vegetation in 2,230 square feet of disturbed area, a functional lift to the site will be provided through the addition of dense native vegetation, which will add value for water quality functions by increasing filtration, hydrological function through slowing water flow, and habitat function by increasing habitat structure. In areas that already have a dense native vegetation community, 11,235 square feet of additional plantings will increase habitat structure and diversity and create a more robust later successional plant community (see Sheet W3 of Appendix A: Mitigation Plan for locations). Removing remaining patches of invasive plants and installing a dense, native plant community, including trees, shrubs, and groundcovers will mitigate for some project impacts and significantly improve the ecological function of the area by providing increased forage and cover opportunities for wildlife, increased stormwater infiltration, reduction in peak 14 stormwater flows, and increased ability to trap and filter sediments that could otherwise enter the wetland and stream. Much of best available science on buffer widths supports larger buffer/core habitat for wetland and riparian wildlife (Hruby, 2014). The location of the proposed development supports this, by preserving the overall core habitat of the adjacent greenspace through locating the development on the outside edge. Through the implementation of the provided mitigation plan, impacts to buffer functions are expected to be mitigated from the construction of the new residence. 4 Reasonable Use Exception The strict application of the wetland and stream regulations under FWRC 19.145 would deny all reasonable economic use of the property. The maximum allowed buffer reduction of 25 percent, or a 112.5-foot buffer, would still result in an entirely encumbered buildable area of the site. Additionally, the standard wetland buffer width of 150 feet for Wetland A results in complete encumbrance of the parcel. Thus, neither buffer reduction through enhancement nor buffer averaging are feasible, as there is no unencumbered area with buffer reduction and no unencumbered area available for buffer expansion. No other allowed uses or exemptions exist within the FWRC to allow the proposed development. Therefore, a reasonable use provision is sought. Section 4.1 below addresses the requirements of FWRC 19.145.090 in relation to the proposed development. 4.1 Addressing FWRC 19.145.090: Reasonable Use Provision FWRC 19.145.090 A) The provisions of this section establish a mechanism whereby the provisions of this chapter may be modified or waived on a case -by -case basis if their implementation would deprive an applicant of all reasonable use of the subject property. Response: As discussed above, the strict implementation of FWRC 19.145 would deprive the applicant of all reasonable use of the subject property. The parcel is zoned for single-family residential development and contains an encumbering 150-foot wetland buffer. The site is entirely encumbered by wetland buffer; therefore, buffer averaging is not a feasible option for site development. Additionally, when reduced to the minimum width allowable under FWRC, a 25 percent reduction or a 112.5-foot buffer, the parcel would still be entirely encumbered. Therefore, no possible application of FWRC 19.145 would allow for development of a single- family residence. 15 B) An applicant may apply for a modification or waiver of the provisions of this chapter using process IV; except, that applications for projects on single-family residential lots may use process III. Response: A reasonable use exception for the development of a single-family residential home on a lot zoned for single-family residential development is sought; therefore, the applicant recognizes that the reasonable use exception will be processed as a Process III application and is providing materials necessary to begin the process. C) The city may approve a modification or waiver of the requirements of this chapter on a case -by - case basis based on the following criteria: 1. The application of the provisions of this chapter eliminates all reasonable use of the subject property. Response: As discussed above, the application of FWRC 19.145 eliminates all reasonable use of the subject property. A single-family home would not be allowed under direct implementation of that chapter, despite the parcel being zoned as single-family residential. 2. No feasible and reasonable on -site alternatives to the proposal are possible, such as changes to site layout andlor reduction of impervious improvements. Response: The current layout of the development with the given footprint is oriented as close to the access road and as far away from critical areas as possible. This orientation leads to an overall reduction of impervious improvements as compared to other options considered. The footprint of the residence utilizes a two-story layout to limit size, with the overall footprint the minimum necessary to fulfill the applicant's needs. Additionally, the size of the footprint is compatible with existing adjacent residences in the vicinity. 3. It is solely the implementation of this chapter, and not other factors, that preclude all reasonable use of the subject property. Response: The only factor that precludes the reasonable use of the subject property is the encumbering wetland buffer as implemented by FWRC 19.145.090. 4. The applicant has in no way created or exacerbated the condition that forms the limitation on the use of the subject property, nor in any way contributed to such limitation. Response: The applicant obtained the subject property in October of 2019. The applicant has made no changes to the subject property that would have created or exacerbated Wetland A or Stream A, nor in any way contributed to the site limitation. 16 5. The waiver or modification will not lead to, create nor significantly increase the risk of injury or death to any person or damage to improvements on or off the subject property. Response: As outlined in the arborist and geotechnical reports (Appendices C and D), modification to the site will be made in accordance to best management practices that will insure that there is no risk of injury, or death to any person or damage to improvements on or off the subject property. 6. Any alteration of a critical area approved under this section shall be subject to appropriate conditions and will require mitigation under an approved mitigation plan. Response: No direct impacts to critical areas are proposed. All impacts to wetland and stream buffers will be mitigated as outlined in response to 3.4 above. The mitigation plan for the site is outlined in Appendix D, Federal Way Afichuk RUE Mitigation Plan, and will be submitted to the City for approval. D) If the city grants a request under this section, it shall grant the minimum necessary to provide the applicant with some reasonable use of the subject property, considering the factors described in subsections (3)(a) through (e) of this section. Any approval or waiver of requirements shall result in the minimum possible impacts to the function and values and/or risks associated with proposed improvements on affected critical areas. The city may impose limitations, mitigation under an approved mitigation plan, conditions and/or restrictions it considers appropriate to reduce or eliminate any undesirable effects or adverse impacts of granting a request under this section. Response: The applicant recognizes that this process is dictated by the City and is aware that they will need to work with the City in order to receive approval. 5 Conclusion The applicant proposes construction of a single-family house, driveway access, and a small yard on parcel 7202500080. The parcel is encumbered by one wetland, one stream, and their associated buffers. A reasonable use exception is sought to allow for reduction of the wetland buffer beyond the maximum allowed by code, in conjunction with a wetland buffer enhancement plan. The proposed buffer enhancement will result in a functional lift of ecological functions. 17 References GeoResoources. 2020. Afichuk, Geologic Hazard Assessment. Fife, WA. Hruby, T. 2014. Washington State Wetland Rating System for Western Washington: 2014 Update. (Publication #14-06-029). Olympia, WA: Washington Department of Ecology. The Watershed Company. 2020. Afichuk, Tree Inventory Report. Kirkland, WA. The Watershed Company. 2020. Afichuk Property, Stream Delineation Report. Kirkland, WA. m Appendix A RUE MITIGATION PLAN CONIC WALL x FOUND REBAR/CAP °0� LS# 7022 �ti SDMH / 0.90'N & 0.43'E ° RIM=110.15' OF PROP COP IE 8"PVC=102.64'(N.) IE 12"CPEP=103.35'(NE.) IE 12"CPEP=103.73'(SW.) �IE 12"CPEP=102.30'(NW.) 1°co / N 89°20'42" W 139.51' 108.2 SO � CB (TYPE 1) / RIM=109.87' °es / 1 IE 12"CPEP =108.07'(NE.)/ 1322 WF Al 36" MA WF / W A�11L WF �/ WMA 11R / / 1328 � 1321 1327 >>,. CON 11- o° W 26" 8", 12", (2) 1 MA " 28", MA 1326 W W ,ti M WA I 1329 20" MA 12" MA I "HDP=110-111' �' _ _ �' � 22" AL 22°° M "' W 1330 1323 WMA IOR W W Wy 1315 1 „ AL ` 1324 22" NOTES 1. OHWM AND WETLAND DELINEATION COMPLETED BY THE WATERSHED COMPANY ON DECEMBER 11, 2019 (750 6TH STREET SOUTH; KIRKLAND, WA 98033; 425-9822-5242). SEE DELINEATION REPORT BY THE WATERSHED COMPANY (DATED DECEMBER 19, 2019) FOR FURTHER DETAILS. 2. WETLAND BUFFER IS DETERMINED TO BE 150 FEET. WETLAND BUFFER ENCUMBERS ENTIRETY OF PARCEL IS NOT VISIBLE WITHIN PLAN EXTENTS. 3. SURVEY (DATED DECEMBER 31, 2019) PROVIDED BY TERRANE (10801 MAIN STREET, SUITE 102, BELLEVUE, WA 98004; 425-458-4488). SHEET INDEX W1 EXISTING CONDITIONS W2 PROPOSEDIMPACTS W3 MITIGATION AND PLANTING PLAN W4 PLANT INSTALLATION SPECIFICATIONS AND SCHEDULES i W5 MITIGATION AND PLANT INSTALLATION DETAILS } W6 MITIGATION PLAN NOTES ' 1 AL 13251331 * ' 14" A * � s 8 AL WF WMA 1so.1 � _ f > WF (L3 W O cc1314 � o 4I „ AL 1332 0 1318* \ 7 1317* 1316* MA 9R 1 " AL w WF / W 9L � / �O� 1310 - L _ �O1312 1339 - 8„ 1313 1309 1 AL 1333 ' 14" A � o O F / WMA4s� �� 81 A 1334* AP I � W 8" A D 1340 1308* 1307 S 8" � •v •v W WF / W A 8 10" 35 / STREAM A, STREAM WF TYPE Ns \ BUFFER W W / A (35 BUFFER) 38" MA ��000 1306 Q - - x W W W O AL / A �W W 1305 WF /AMA L / FOUND REBAR/CAP I 0 �� WETLAND A, I / CATEGORY II WF / W W LS# 48745 AL 8" 0.0 S 1338 OFPRO COP .'w wA 5 _ ° (150' BUFFER) `3p AL L )4„ AL, ,661304.1 W A 1336 ' I 14 12" AL(D 1 e 1 1 160.4x d 1303 14" ALD 15' BLDG * ' FOUND RE - SETBACK - �W (2) 10" MAP 1335 LS# 7022 PER PLAT _ Icp , ° 0.05'S & 0.09 ,O D 1 OF PROP COP �,, d a IE 12"HDP=144.24' F WMA R SSM H O 1302 ° / I RIM=175.30' ° ` d �� WF DP i E 8"CONC�SEe%W;) a 170� 1337 WF 9 ♦ 0 =158.70'(C.C.)e'GRADEBR s� �" A� ' de EAK , � AL WF�/-W N a ° � , 62.5= WF DP4 APPLICANT PARCEL i o #72 2 1301 P3 ' 0 500080 1 D d / WF MA 2 e / d d J WF / A 2 a �7�53 160.5- F ND REBAR �5 ♦ �; �� AT ROP COP ELEC CAL EASEM PE PLAT / ♦♦ 1479 WF / W A 1 L W WF / W A l 10 STORM EA MENT / ♦' s \15' BLDG / / � ♦max ��, � .v O S _ O /� ° ''�♦ O V PER PLAT 'sue/ �i66 ♦♦ �� 175.3 /00 \ a \,, / / , ♦ E x E ' O ♦ \ �� gRE AK ��e � e 000000 6�. 40 x O 175,73�0 175.72 So O �L ♦� \ ♦ 40 �♦♦ ♦♦FOUND REBARx"� 0 0.67'S & 0.93'E 5®� OF PROP COR `'Dr;" sow f EXISTING CONDITIONS SCALE 1:10 THE WATERSHED COMPANY 750 Sixth Street South Kirkland WA 98033 p 425.822.5242 www.watershedco.com Science & Design W7 TREE RETENTION AND REMOVAL PLAN W8 TREE RETENTION AND REMOVAL NOTES - zv� (V y\a�a J Q W w 0 >; etit 1--I O 00 Z o z Q _ QU)LO Puget N a �-+ o Sound • g a u m �i f ��.� �9�u co �pC� LL N W it FederalUj Q Way W W ILL O w z PROJECT a , v � LOCATION , 3 + < k co +/y LLe 'k �, LL VICINITY MAPS im NTS O z LD ' w LEGEND Z Q PARCEL BOUNDARY � O z H �:: O �Fr< W W� DELINEATED WETLAND BOUNDARY z 0 0 G7 w H IW W W W W W_ APPROXIMATE WETLAND BOUNDARY o 0 Uj DELINEATED OHWM Q N w �a STREAM BUFFER (35') ^ L.L O Z 0 SIGNIFICANT TREE SHEET SIZE: ORIGINAL PLAN IS 22" x 34". SCALE ACCORDINGLY. w PROJECT MANAGER: GB z DESIGNED: RH LL DRAFTED: RH CHECKED: AMC, GB JOB NUMBER: m 191123 W " 0' 5' 10' 20' 40' SHEET NUMBER: W1 OF8W a © 2020 -The Watershed Company 0 M r 32 126 128 736 \ 736 130\ 110 � 7,14 z PROPOSED IMPACTS SCALE 1:10 ---------- ------ ----------- -- 'O\ 4 0 I re NOTES 1. SITE PLAN (DATED MAY 22, 2020) PROVIDED BY URBAN DESIGN GROUP (879 RAINIER AVENE N, SUITE A200; RENTON, WA 89057; 206-838-8250). 2. SEE SHEET W7 FOR TREE RETENTION AND REMOVAL PLAN. LEGEND EXISTING CONDITIONS PARCEL BOUNDARY DELINEATED WETLAND BOUNDARY APPROXIMATE WETLAND BOUNDARY DELINEATED OHWM STREAM BUFFER (35') SIGNIFICANT TREE PROPOSED CONDITIONS LIMITS OF DEVELOPMENT / CONSTRUCTION PERMANENT BUFFER IMPACTS (4,455 SF TOTAL) IMPERVIOUS AREA (3,185 SF) YARD / SETBACK AREA (1,270 SF) z 0 U OC (n Z O U OC O LL z W Cn W 0' 5' 10, 20' 40' © 2020 - The Watershed Company THE WATERSHED COMPANY 750 Sixth Street South Kirkland WA 98033 p 425.822.5242 www.watershedco.com Science & Design Z U M Q LL J Q w o ~ w o rn Z � z� < c) < O_cf)N3: 0 N >- Qi Q OC OC � Q (EOM J �LLN w Q — U 0 U) 0� w LULU><<o OC � w OCQT `L Q n W w w r'r n mX U z O w 06 z J H O a O m U 0 J W O N H N_ Q O Q N O T 0 z T SHEET SIZE: ORIGINAL PLAN IS 22" x 34". SCALE ACCORDINGLY. PROJECT MANAGER: GB w z DESIGNED: RH Uj DRAFTED: RH LL CHECKED: AMC, GB JOB NUMBER: m 191123 W z SHEET NUMBER: a W2 OF 8W 0 NOTES 1. WETLAND BUFFER IS DETERMINED TO BE 150 FEET. BUFFER ENCUMBERS ENTIRETY OF PARCEL IS ARE NOT SHOWN WITHIN PLAN EXTENTS. 2. SEE SHEET W4 FOR PLANT INSTALLATION SPECIFICATION AND SCHEDULES. 3. SEE SHEET W5 FOR MITIGATION AND PLANTING DETAILS. THE WATERSHED COMPANY 750 Sixth Street South Kirkland WA 98033 p 425.822.5242 www.watershedco.com Science & Design U U LJ LJ U U U U U U LJ U LJ LJ U LJ LJ LJ LJ LJ LJ LJ LJ LJ W �r . 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SCALE ACCORDINGLY. PROJECT MANAGER: GB DESIGNED: RH DRAFTED: RH CHECKED: AMC, GB w z u' JOB NUMBER: m 191123 W z SHEET NUMBER: a W3 OF 8 a 0 PLANT INSTALLATION SPECIFICATIONS GENERAL NOTES QUALITY ASSURANCE 1. PLANTS SHALL MEET OR EXCEED THE SPECIFICATIONS OF FEDERAL, STATE, AND LOCAL LAWS REQUIRING INSPECTION FOR PLANT DISEASE AND INSECT CONTROL. 2. PLANTS SHALL BE HEALTHY, VIGOROUS, AND WELL -FORMED, WITH WELL DEVELOPED, FIBROUS ROOT SYSTEMS, FREE FROM DEAD BRANCHES OR ROOTS. PLANTS SHALL BE FREE FROM DAMAGE CAUSED BY TEMPERATURE EXTREMES, LACK OR EXCESS OF MOISTURE, INSECTS, DISEASE, AND MECHANICAL INJURY. PLANTS IN LEAF SHALL BE WELL FOLIATED AND OF GOOD COLOR. PLANTS SHALL BE HABITUATED TO THE OUTDOOR ENVIRONMENTAL CONDITIONS INTO WHICH THEY WILL BE PLANTED (HARDENED -OFF). 3. TREES WITH DAMAGED, CROOKED, MULTIPLE OR BROKEN LEADERS WILL BE REJECTED. WOODY PLANTS WITH ABRASIONS OF THE BARK OR SUN SCALD WILL BE REJECTED. 4. NOMENCLATURE: PLANT NAMES SHALL CONFORM TO FLORA OF THE PACIFIC NORTHWEST BY HITCHCOCK AND CRONQUIST, UNIVERSITY OF WASHINGTON PRESS, 1973 AND/OR TO A FIELD GUIDE TO THE COMMON WETLAND PLANTS OF WESTERN WASHINGTON & NORTHWESTERN OREGON, ED. SARAH SPEAR COOKE, SEATTLE AUDUBON SOCIETY, 1997. DEFINITIONS 1. PLANTS/PLANT MATERIALS. PLANTS AND PLANT MATERIALS SHALL INCLUDE ANY LIVE PLANT MATERIAL USED ON THE PROJECT. THIS INCLUDES BUT IS NOT LIMITED TO CONTAINER GROWN, B&B OR BAREROOT PLANTS; LIVE STAKES AND FASCINES (WATTLES); TUBERS, CORMS, BULBS, ETC..; SPRIGS, PLUGS, AND LINERS. 2. CONTAINER GROWN. CONTAINER GROWN PLANTS ARE THOSE WHOSE ROOTBALLS ARE ENCLOSED IN A POT OR BAG IN WHICH THAT PLANT GREW. SUBSTITUTIONS 1. IT IS THE CONTRACTOR'S RESPONSIBILITY TO OBTAIN SPECIFIED MATERIALS IN ADVANCE IF SPECIAL GROWING, MARKETING OR OTHER ARRANGEMENTS MUST BE MADE IN ORDER TO SUPPLY SPECIFIED MATERIALS. 2. SUBSTITUTION OF PLANT MATERIALS NOT ON THE PROJECT LIST WILL NOT BE PERMITTED UNLESS AUTHORIZED IN WRITING BY THE RESTORATION CONSULTANT. 3. IF PROOF IS SUBMITTED THAT ANY PLANT MATERIAL SPECIFIED IS NOT OBTAINABLE, A PROPOSAL WILL BE CONSIDERED FOR USE OF THE NEAREST EQUIVALENT SIZE OR ALTERNATIVE SPECIES, WITH CORRESPONDING ADJUSTMENT OF CONTRACT PRICE. 4. SUCH PROOF WILL BE SUBSTANTIATED AND SUBMITTED IN WRITING TO THE CONSULTANT AT LEAST 30 DAYS PRIOR TO START OF WORK UNDER THIS SECTION. INSPECTION 1. PLANTS SHALL BE SUBJECT TO INSPECTION AND APPROVAL BY THE RESTORATION CONSULTANT FOR CONFORMANCE TO SPECIFICATIONS, EITHER AT TIME OF DELIVERY ON -SITE OR AT THE GROWER'S NURSERY. APPROVAL OF PLANT MATERIALS AT ANY TIME SHALL NOT IMPAIR THE SUBSEQUENT RIGHT OF INSPECTION AND REJECTION DURING PROGRESS OF THE WORK. 2. PLANTS INSPECTED ON SITE AND REJECTED FOR NOT MEETING SPECIFICATIONS MUST BE REMOVED IMMEDIATELY FROM SITE OR RED -TAGGED AND REMOVED AS SOON AS POSSIBLE. 3. THE RESTORATION CONSULTANT MAY ELECT TO INSPECT PLANT MATERIALS AT THE PLACE OF GROWTH. AFTER INSPECTION AND ACCEPTANCE, THE RESTORATION CONSULTANT MAY REQUIRE THE INSPECTED PLANTS BE LABELED AND RESERVED FOR PROJECT. SUBSTITUTION OF THESE PLANTS WITH OTHER INDIVIDUALS, EVEN OF THE SAME SPECIES AND SIZE, IS UNACCEPTABLE. MEASUREMENT OF PLANTS 1. PLANTS SHALL CONFORM TO SIZES SPECIFIED UNLESS SUBSTITUTIONS ARE MADE AS OUTLINED IN THIS CONTRACT. 2. HEIGHT AND SPREAD DIMENSIONS SPECIFIED REFER TO MAIN BODY OF PLANT AND NOT BRANCH OR ROOT TIP TO TIP. PLANT DIMENSIONS SHALL BE MEASURED WHEN THEIR BRANCHES OR ROOTS ARE IN THEIR NORMAL POSITION. 3. WHERE A RANGE OF SIZE IS GIVEN, NO PLANT SHALL BE LESS THAN THE MINIMUM SIZE AND AT LEAST 50% OF THE PLANTS SHALL BE AS LARGE AS THE MEDIAN OF THE SIZE RANGE. (EXAMPLE: IF THE SIZE RANGE IS 12" TO 18", AT LEAST 50% OF PLANTS MUST BE 15" TALL.). SUBMITTALS PROPOSED PLANT SOURCES 1. WITHIN 45 DAYS AFTER AWARD OF THE CONTRACT, SUBMIT A COMPLETE LIST OF PLANT MATERIALS PROPOSED TO BE PROVIDED DEMONSTRATING CONFORMANCE WITH THE REQUIREMENTS SPECIFIED. INCLUDE THE NAMES AND ADDRESSES OF ALL GROWERS AND NURSERIES. PRODUCT CERTIFICATES 1. PLANT MATERIALS LIST - SUBMIT DOCUMENTATION TO CONSULTANT AT LEAST 30 DAYS PRIOR TO START OF WORK UNDER THIS SECTION THAT PLANT MATERIALS HAVE BEEN ORDERED. ARRANGE PROCEDURE FOR INSPECTION OF PLANT MATERIAL WITH CONSULTANT AT TIME OF SUBMISSION. 2. HAVE COPIES OF VENDOR'S OR GROWERS' INVOICES OR PACKING SLIPS FOR ALL PLANTS ON SITE DURING INSTALLATION. INVOICE OR PACKING SLIP SHOULD LIST SPECIES BY SCIENTIFIC NAME, QUANTITY, AND DATE DELIVERED (AND GENETIC ORIGIN IF THAT INFORMATION WAS PREVIOUSLY REQUESTED). DELIVERY, HANDLING, & STORAGE NOTIFICATION CONTRACTOR MUST NOTIFY CONSULTANT 48 HOURS OR MORE IN ADVANCE OF DELIVERIES SO THAT CONSULTANT MAY ARRANGE FOR INSPECTION. PLANT MATERIALS 1. TRANSPORTATION - DURING SHIPPING, PLANTS SHALL BE PACKED TO PROVIDE PROTECTION AGAINST CLIMATE EXTREMES, BREAKAGE AND DRYING. PROPER VENTILATION AND PREVENTION OF DAMAGE TO BARK, BRANCHES, AND ROOT SYSTEMS MUST BE ENSURED. 2. SCHEDULING AND STORAGE - PLANTS SHALL BE DELIVERED AS CLOSE TO PLANTING AS POSSIBLE. PLANTS IN STORAGE MUST BE PROTECTED AGAINST ANY CONDITION THAT IS DETRIMENTAL TO THEIR CONTINUED HEALTH AND VIGOR. 3. HANDLING - PLANT MATERIALS SHALL NOT BE HANDLED BY THE TRUNK, LIMBS, OR FOLIAGE BUT ONLY BY THE CONTAINER, BALL, BOX, OR OTHER PROTECTIVE STRUCTURE, EXCEPT BAREROOT PLANTS SHALL BE KEPT IN BUNDLES UNTIL PLANTING AND THEN HANDLED CAREFULLY BY THE TRUNK OR STEM. 4. LABELS - PLANTS SHALL HAVE DURABLE, LEGIBLE LABELS STATING CORRECT SCIENTIFIC NAME AND SIZE. TEN PERCENT OF CONTAINER GROWN PLANTS IN INDIVIDUAL POTS SHALL BE LABELED. PLANTS SUPPLIED IN FLATS, RACKS, BOXES, BAGS, OR BUNDLES SHALL HAVE ONE LABEL PER GROUP. WARRANTY PLANT WARRANTY PLANTS MUST BE GUARANTEED TO BE TRUE TO SCIENTIFIC NAME AND SPECIFIED SIZE, AND TO BE HEALTHY AND CAPABLE OF VIGOROUS GROWTH. REPLACEMENT 1. PLANTS NOT FOUND MEETING ALL OF THE REQUIRED CONDITIONS AT THE CONSULTANT'S DISCRETION MUST BE REMOVED FROM SITE AND REPLACED IMMEDIATELY AT THE CONTRACTOR'S EXPENSE. 2. PLANTS NOT SURVIVING AFTER ONE YEAR TO BE REPLACED AT THE CONTRACTOR'S EXPENSE. PLANT MATERIAL GENERAL 1. PLANTS SHALL BE NURSERY GROWN IN ACCORDANCE WITH GOOD HORTICULTURAL PRACTICES UNDER CLIMATIC CONDITIONS SIMILAR TO OR MORE SEVERE THAN THOSE OF THE PROJECT SITE. 2. PLANTS SHALL BE TRUE TO SPECIES AND VARIETY OR SUBSPECIES. NO CULTIVARS OR NAMED VARIETIES SHALL BE USED UNLESS SPECIFIED AS SUCH. QUANTITIES SEE PLANT LIST ON ACCOMPANYING PLANS AND PLANT SCHEDULES. ROOT TREATMENT 1. CONTAINER GROWN PLANTS (INCLUDES PLUGS): PLANT ROOT BALLS MUST HOLD TOGETHER WHEN THE PLANT IS REMOVED FROM THE POT, EXCEPT THAT A SMALL AMOUNT OF LOOSE SOIL MAY BE ON THE TOP OF THE ROOTBALL. 2. PLANTS MUST NOT BE ROOT -BOUND; THERE MUST BE NO CIRCLING ROOTS PRESENT IN ANY PLANT INSPECTED. 3. ROOTBALLS THAT HAVE CRACKED OR BROKEN WHEN REMOVED FROM THE CONTAINER SHALL BE REJECTED. PLANT INSTALLATION SPECIFICATIONS AND SCHEDULES NOTES 1. TREES, SHRUBS AND GROUNDCOVERS TO BE GROUPED BY SPECIES IN GROUPS OF 3-9 AND SPACED TRIANGULARLY. 2. SEE SHEET W5 FOR MITIGATION AND PLANT INSTALLATION DETAILS. PLANT SCHEDULE - TYPE 1 PLANTING AREA / BUFFER RESTORATION (2,180 SF) BOTANICAL NAME / COMMON NAME QTY. SIZE SPACING TREES THUJA PLICATA / WESTERN RED CEDAR 5 1 GAL. 9' O.C. TSUGA HETEROPHYLLA / WESTERN HEMLOCK 5 1 GAL. 9' O.C. TREE QUANTITY: 10 SHRUBS ACER CIRCINATUM / VINE MAPLE 5 1 GAL. 5' O.C. CORYLUS CORNUTA / BEAKED HAZELNUT 5 1 GAL. 5' O.C. OEMLERIA CERASIFORMIS / OSOBERRY 12 1 GAL. 5' O.C. RIBES SANGUINEUM / RED FLOWERING CURRANT 12 1 GAL. 5' O.C. ROSA NUTKANA / NOOTKA ROSE 12 1 GAL. 5' O.C. RUBUS SPECTABILIS / SALMONBERRY 12 1 GAL. 5' O.C. SYMPHORICARPOS ALBUS / SNOWBERRY 15 1 GAL. 5' O.C. VACCINIUM OVATUM / EVERGREEN HUCKLEBERRY 15 1 GAL. 5' O.C. SHRUB QUANTITY: 88 GROUNDCOVERS GAULTHERIA SHALLON / SALAL 60 1 GAL. 3' O.C. MAHONIA NERVOSA / DULL OREGON GRAPE 60 1 GAL. 3' O.C. POLYSTICHUM MUNITUM / WESTERN SWORDFERN 60 1 GAL. 3' O.C. GROUNDCOVER QUANTITY: 180 TOTAL PLANT QUANTITY: 278 PLANT SCHEDULE - TYPE 2 PLANTING AREA / UNDERSTORY INFILL (11.450 SF BOTANICAL NAME / COMMON NAME TRFP:C THUJA PLICATA / WESTERN RED CEDAR TSUGA HETEROPHYLLA / WESTERN HEMLOCK TOTAL PLANT QUANTITY QTY. SIZE SPACING 30 1 GAL. 15' O.C. 30 1 GAL. 15' O.C. f z 0 U OC (n Z O U 0 L.L 0 Z 1 W U) 75 W © 2020 - The Watershed Company THE WATERSHED COMPANY 750 Sixth Street South Kirkland WA 98033 425.822.5242 www.watershedco.com Science & Design Z U M � Q LL J Q W 00 o 1--I W O d Z0 ZOC < o c) < O_�UN3: 0 CV > U) (EOM J LL N Lu Q - U 0 � � W W W >< < C) � � X W Q r IL F-� L U m0� U z O w 06 z J J H O a �o m U 0 U)P: o 0 N w NO a Q N O T 0 z T SHEET SIZE: ORIGINAL PLAN IS 22" x 34". SCALE ACCORDINGLY. PROJECT MANAGER: GB DESIGNED: RH DRAFTED: RH CHECKED: AMC, GB w z uj JOB NUMBER: ca m 191123 W z SHEET NUMBER: a W4 OF 8w 0 NOTE: INSTALL COIR LOGS PARALLEL TO SLOPE CONTOUR PER SURFACE WATER DESIGN MANUAL - APPENDIX D (D.2.1.2.5) UNTREATED 4" X 4" X 24" WOOD STAKE ACCUMULATED SEDIMENT, ORGANIC MATTER, NATIVE SEEDS, ETC. EROSION CONTROL COIR FIBER LOGS (BIODEGRADEABLE) STAKE THROUGH CENTER OF COIR LOG ENTRENCH COIR LOG 5-7 INCHES OR 1/2 - 2/3 INTO SUBGRADE COIR LOG Scale: NTS 2" COMPOST 4" WOOD PLANTING AREA PREPARATION CHIP STEP 1 PIT MULCH REMOVE NON-NATIVE PLANT AMEND SPECIES. WORK WITHIN EXISTING TREE ROOT ZONES SHALL BE DONE BY HAND. 2X MIN DIA STEP 2 ROOTBALL i 4" i PLACE 0.13 CF / 1 GALLON OF COMPOST PER PLANTING PIT AND \\\\\ ROOTBALL \\ DEPTH MIX WITH EXCAVATED SOIL. STEP 3 \/\\\ \ LEAVE MINIMUM ONE (1) INCH LAYER \ OF AMENDED SOIL AT THE BOTTOM \ OF THE PIT THEN INSTALL PLANT (SEE \/\\ \\ /\\/\ /\\// /\\/\ PLANTING DETAIL). BACKFILL WITH AMENDED SOIL. \/\\/\ \/\\/\ STEP 4 \ \ \ \ \ \ \ \ \ \ INSTALL MULCH LAYER FOUR (4) INCHES DEEP. HOLD BACK MULCH EXISTING STEP 1 STEP 2 STEP 3 STEP 4 FROM TRUNKS /STEMS. SEQUENCE OF WORK - NOT TO SCALE MITIGATION AREA SITE PREPARATION Scale: NTS MITIGATION AND PLANT INSTALLATION DETAILS 0 c� 8'-0" MAX. 6" x 6" ROUGH CUT CEDAR POST NOTCHED TO CONTAIN AND CONCEAL RAIL CONNECTION 2" X 6" ROUGH CUT CEDAR RAILS SPLIT RAIL FENCE 2X MIN DIA. ROOTBALL CONTAINER PLANTING FINISHED GRADE COMPACTED III GRAVEL BASE. NO CONCRETE IS TO BE PLACED IN SENSITIVE AREAS. COMPACTED SUBGRADE Scale: NTS NOTES: 1. PLANTING PIT SHALL NOT BE LESS THAN (2) TIMES THE WIDTH OF THE ROOT BALL DIA. 2. LOOSEN SIDES AND BOTTOM OF PLANT PIT 3. REMOVE FROM POT & ROUGH -UP ROOT BALL BEFORE INSTALLING. IF PLANT IS EXCEPTIONALLY ROOT -BOUND OR CONTAINS CIRCLING ROOTS, DO NOT PLANT AND RETURN TO NURSERY FOR AN ACCEPTABLE ALTERNATIVE. IF B&B STOCK, REMOVE ALL TWINE/WIRE, & REMOVE BURLAP FROM TOP 1/3RD OF ROOTBALL PRIOR TO PLANTING (NOTE: CONTAINER STOCK PREFERRED) 4. SOAK PLANTING PIT AFTER PLANTING 4" COARSE WOOD CHIP MULCH IN ALL PLANTING BEDS. HOLD BACK MULCH FROM TRUNK/STEMS. REMOVE DEBRIS AND LARGE ROCKS AND BACKFILL WITH NATIVE SOIL. FIRM UP SOIL AROUND PLANT. Scale: NTS z 0 0 L.L 0 Z 1 w U) 75 W © 2020 - The Watershed Company 2 THE WATERSHED COMPANY 750 Sixth Street South Kirkland WA 98033 p 425.822.5242 www.watershedco.com Science & Design Z U M �QLL w J Q o ~ w o rn Z � Z� < c) Ocv � �ON> Qi Q OC OC � Q (EOM J KN ILw Q — U 0 W 0� w LULU><<o OC � w OCQT `L Q n W w w r'r n m 0� U z O w 06 z J Q H O a �o m U 0 U o 0 N W NO Q Q N O T 0 z T SHEET SIZE: ORIGINAL PLAN IS 22" x 34". SCALE ACCORDINGLY. PROJECT MANAGER: GB w z DESIGNED: RH uj DRAFTED: RH CHECKED: AMC, GB JOB NUMBER: ca m 191123 W z SHEET NUMBER: a W5 OF 8W 0 THE MITIGATION PLAN NOTES WATERSHED MITIGATION PLAN THE FORMAL MONITORING VISIT SHALL RECORD AND REPORT THE FOLLOWING IN AN ANNUAL OR PLUM) THROUGHOUT MITIGATION AREA AND IMMEDIATELY TREAT STEM (DAUBING OR COMPANY REPORT SUBMITTED TO THE CITY OF BELLEVUE: PAINTING) WITH APPROPRIATE HERBICIDE. PERSON APPLYING HERBICIDE SHALL BE THIS PLAN HAS BEEN PREPARED AS MITIGATION FOR IMPACTS TO ON -SITE CRITICAL AREA STATE -LICENSED. DO NOT REMOVE SUBSURFACE ROOTS. BUFFERS. THE PROPERTY IS ENTIRELY ENCUMBERED BY STREAM AND WETLAND BUFFERS. 1. VISUAL ASSESSMENT OF THE OVERALL MITIGATION AREA. D. AVOID AND MINIMIZE DISTURBANCE AND/OR COMPACTION TO ROOTS OF ESTABLISHED 750 Sixth Street South PERMANENT BUFFER IMPACTS WILL OCCUR WITH THE CONSTRUCTION OF A SINGLE FAMILY 2. YEAR-1 COUNTS OF LIVE AND DEAD PLANTS BY SPECIES. YEAR-2 THROUGH YEAR-5 COUNTS OF NATIVE TREES TO BE RETAINED WHEN REMOVING VEGETATION FROM WITHIN TREE Kirkland WA 98033 RESIDENCE, TO BE PERMITTED THROUGH THE REASONABLE USE EXCEPTION PROCESS. THE ESTABLISHED NATIVE TREES AND SHRUBS BY SPECIES, TO THE EXTENT FEASIBLE. DRIPLINES. PROPOSED DEVELOPMENT AREA WILL IMPACT A TOTAL OF 4,455 SQUARE FEET WITHIN CRITICAL 425.822.5242 AREA BUFFERS. THE MITIGATION PLAN SEEKS TO ENHANCE A SUBSTANTIAL PORTION OF ON -SITE 3. COUNTS OF DEAD PLANTS WHERE MORTALITY IS SIGNIFICANT IN ANY MONITORING YEAR. 3. BLANKET -MULCH CLEARED AREAS WITH WOOD MULCH, FOUR INCHES THICK. www.watershedco.com STREAM AND WETLAND BUFFERS. 4. ESTIMATE OF NATIVE COVER IN THE MITIGATION AREA. A. ENSURE MULCH DOES NOT TOUCH STEMS OF EXISTING (OR INSTALLED) VEGETATION. SEE TO OFFSET PROJECT IMPACTS, THE PLAN CALLS FOR THE ENHANCEMENT OF A TOTAL OF 13,465 5. ESTIMATE OF NON-NATIVE, INVASIVE WEED COVER IN THE MITIGATION AREA. PLANTING DETAIL ON SHEET W5. Science & Design SQUARE FEET OF STREAM AND WETLAND BUFFERS. 2,230 SQUARE FEET OF BUFFER AREA WILL BE 6. TABULATION OF ESTABLISHED NATIVE SPECIES, INCLUDING BOTH PLANTED AND VOLUNTEER MITIGATION PLANTING AND IRRIGATION ENHANCED THROUGH THE REMOVAL OF NON-NATIVE PLANTS AND PLANTING OF NATIVE TREES, SPECIES. SHRUBS AND GROUNDCOVER. TREE SPECIES PROPOSED INCLUDE WESTERN RED CEDAR AND 7. PHOTOGRAPHIC DOCUMENTATION FROM AT LEAST THREE FIXED REFERENCE POINTS. 1. INSTALL MITIGATION PLANTS DURING THE DORMANT SEASON (OCTOBER 15 - MARCH 1). AND WESTERN HEMLOCK. SHRUBS INCLUDE VINE MAPLE, BEAKED HAZELNUT, OSOBERRY, RED A. PREPARE A PLANTING PIT FOR EACH PLANT THROUGH BLANKET WOOD MULCH AND INSTALL FLOWERING CURRANT, NOOTKA ROSE, SALMONBERRY, SNOWBERRY, AND EVERGREEN 8. ANY INTRUSIONS INTO OR CLEARING OF THE PLANTING AREAS, VANDALISM, OR OTHER PER THE PLANTING DETAILS. HUCKLEBERRY. PROPOSED GROUNDCOVERS INCLUDE SAAAL, DULL OREGON GRAPE, AND ACTIONS THAT IMPAIR THE INTENDED FUNCTIONS OF THE MITIGATION AREA. 2. INSTALL A TEMPORARY, ABOVE GROUND IRRIGATION SYSTEM TO PROVIDE FULL WESTERN SWORDFERN. THE REMAINING 11,235 SQUARE FEET OF BUFFER ON THE PROPERTY 9. RECOMMENDATIONS FOR MAINTENANCE OR REPAIR OF ANY PORTION OF THE MITIGATION COVERAGE TO ALL INSTALLED PLANTS WITHIN THE RESTORATION AREA. WILL BE ENHANCED WITH THE INFILL PLANTING OF CONIFERS INCLUDING WESTERN RED CEDAR AREA. AND AND WESTERN HEMLOCK. THIS AREA IS CURRENTLY DOMINATED BY RED ALDER AND MATERIAL SPECIFICATIONS AND DEFINITIONS SALMONBERRY AND GENERALLY LACKS CONIFER COVER. OVERALL, A TOTAL OF 70 TREES, 88 MAINTENANCE SHRUBS, AND 180 GROUNDCOVER PLANTS COMPRISING THESE SPECIES WILL BE INSTALLED. THE SITE WILL BE MAINTAINED IN ACCORDANCE WITH THE FOLLOWING INSTRUCTIONS FOR AT 1. FERTILIZER (FOR NEAR AQUATIC ENVIRONMENTS): SLOW -RELEASE, PHOSPHOROUS -FREE LEAST FIVE YEARS FOLLOWING COMPLETION OF CONSTRUCTION: GRANULAR FERTILIZER. LABEL MUST INDICATE THAT PRODUCT IS SAFE FOR AQUATIC MAINTENANCE AND MONITORING PLAN ENVIRONMENTS. FOLLOW MANUFACTURER'S INSTRUCTIONS FOR USE. KEEP FERTILIZER IN 1. FOLLOW THE RECOMMENDATIONS NOTED IN THE PREVIOUS MONITORING SITE VISIT. WEATHER -TIGHT CONTAINER WHILE ON -SITE. FERTILIZER IS ONLY TO BE APPLIED IN YEARS 2 THE SITE SHALL BE MAINTAINED AND MONITORED FOR FIVE YEARS FOLLOWING SUCCESSFUL 2. GENERAL WEEDING FOR ALL PLANTED AREAS: AND 3, NOT IN YEAR ONE. U INSTALLATION. COMPONENTS OF THE 5-YEAR MAINTENANCE AND MONITORING PLAN ARE 2. IRRIGATION SYSTEM: AUTOMATED SYSTEM CAPABLE OF DELIVERING AT LEAST ONE INCH OF z M DETAILED BELOW. A. AT LEAST TWICE YEARLY, REMOVE ALL COMPETING WEEDS AND WEED ROOTS FROM WATER PER WEEK FROM JUNE 1 THROUGH SEPTEMBER 30 FOR THE FIRST TWO YEARS J LL w C:,00 O BENEATH EACH INSTALLED PLANT AND ANY DESIRABLE VOLUNTEER VEGETATION TO A DISTANCE OF 18 INCHES FROM THE MAIN PLANT STEM. WEEDING SHOULD OCCUR AT LEAST FOLLOWING INSTALLATION. 1--I 0 w O 00 GOALS TWICE DURING THE SPRING AND SUMMER. FREQUENT WEEDING WILL RESULT IN LOWER 3. RESTORATION PROFESSIONAL: WATERSHED COMPANY [(425) 822-5242] PERSONNEL, OR OTHER z 0 z 0O 1. ESTABLISH DENSE NATIVE VEGETATION THAT IS APPROPRIATE TO THE ECO-REGION AND SITE. MORTALITY, LOWER PLANT REPLACEMENT COSTS, AND INCREASED LIKELIHOOD THAT THE PERSONS QUALIFIED TO EVALUATE ENVIRONMENTAL RESTORATION PROJECTS. Q C) Q 2. LIMIT INVASIVE AND/OR NOXIOUS WEED COVER ON -SITE. PLAN MEETS PERFORMANCE STANDARDS BY YEAR 5. 4. WOODCHIP MULCH: "ARBORIST CHIPS" (CHIPPED WOODY MATERIAL) APPROXIMATELY ONE TO O CV 3. INCREASE HABITAT COVER AND REFUGE FOR URBAN WILDLIFE SPECIES. PROVIDE PERCHING, B. MORE FREQUENT WEEDING MAY BE NECESSARY DEPENDING ON WEED CONDITIONS THAT THREE INCHES IN MAXIMUM DIMENSION (NOT SAWDUST). THIS MATERIAL IS COMMONLY �"� U) C) N NESTING AND FORAGING HABITAT FOR NATIVE BIRDS. DEVELOP AFTER PLAN INSTALLATION. AVAILABLE IN LARGE QUANTITIES FROM ARBORISTS OR TREE -PRUNING COMPANIES. MULCH SHALL NOT CONTAIN APPRECIABLE QUANTITIES OF GARBAGE PLASTIC METAL SOIL AND c Q C. DO NOT WEED THE AREA NEAR THE PLANT BASES WITH STRING TRIMMER (WEED M � WHACKER/WEED EATER). NATIVE PLANTS ARE EASILY DAMAGED OR KILLED, AND WEEDS DIMENSIONAL LUMBER OR CONSTRUCTION/DEMOLITION DEBRIS. L5 O 0 J PERFORMANCE STANDARDS EASILY RECOVER AFTER TRIMMING. 5. COMPOST: COMPOST SHALL MEET WSDOT STANDARDS SPECIFICATIONS FOR ROAD, BRIDGE, U_ (y Lij J 04(8) FOR FINE COMPOST 14 9- .. � - Q THE STANDARDS LISTED BELOW WILL BE USED TO JUDGE THE SUCCESS OF THE INSTALLATION D. SELECTIVE APPLICATIONS OF HERBICIDE MAY BE NEEDED TO CONTROL INVASIVE WEEDS, AND MUNICIPAL CONSTRUCTION, CC OVER TIME. IF PERFORMANCE STANDARDS ARE MET AT THE END OF YEAR 5, THE SITE WILL THEN ESPECIALLY WHEN INTERMIXED WITH NATIVE SPECIES. HERBICIDE APPLICATION, WHEN CONTINGENCIES G 0 U) 0� w BE DEEMED SUCCESSFUL AND THE PERFORMANCE SECURITY BOND WILL BE ELIGIBLE FOR NECESSARY, SHALL BE CONDUCTED ONLY BY A STATE -LICENSED APPLICATOR. w W >< < C) RELEASE BY THE CITY OF FEDERAL WAY. 3. APPLY SLOW -RELEASE, GRANULAR FERTILIZER TO EACH INSTALLED PLANT ANNUALLY IN THE IF THERE IS A SIGNIFICANT PROBLEM WITH THE RESTORATION AREAS MEETING PERFORMANCE F-��I � >< J SPRING (BY JUNE 1) OF YEARS 2 THROUGH 5. STANDARDS, A CONTINGENCY PLAN WILL BE DEVELOPED AND IMPLEMENTED. CONTINGENCY z L F-�-I Q T 1. SURVIVAL: THIS STANDARD CAN BE MET THROUGH PLANT ESTABLISHMENT OR THROUGH 4REPLACE MULCH AS NECESSARY TO MAINTAIN A 4-INCH-THICK LAYER, RETAIN SOIL MOISTURE, PLANS CAN INCLUDE, BUT ARE NOT LIMITED TO: SOIL AMENDMENT, ADDITIONAL PLANT O 0- REPLANTING IN THE FOLLOWING DORMANT SEASON AS NECESSARY TO ACHIEVE THE . INSTALLATION, AND PLANT SUBSTITUTIONS OF TYPE, SIZE, QUANTITY, AND LOCATION. w REQUIRED NUMBERS. AND LIMIT WEEDS. A. ACHIEVE 100% SURVIVAL OF ALL INSTALLED PLANTS BY THE END OF YEAR 1 (FROM DATE OF 5. REPLACE EACH PLANT FOUND DEAD IN THE SUMMER MONITORING VISITS DURING THE PLANT INSTALLATION). UPCOMING DORMANT SEASON (OCTOBER 15 TO MARCH 1), FOR BEST SURVIVAL. U B. ACHIEVE 90% SURVIVAL OF ALL INSTALLED PLANTS BY THE END OF YEAR 2 (FROM DATE OF 6. THE PROPERTY OWNER WILL ENSURE THAT WATER IS PROVIDED FOR THE ENTIRE PLANTED PLANT INSTALLATION). AREA WITH A MINIMUM OF 1 INCH OF WATER PER WEEK FROM JUNE 1 THROUGH SEPTEMBER 30 n/ C. ACHIEVE 85% SURVIVAL OF ALL INSTALLED CONIFER TREES BY THE END OF YEAR 3, 4, AND FOR THE FIRST TWO YEARS FOLLOWING INSTALLATION, THROUGH THE OPERATION OF ATEMPORARY IRRIGATION SYSTEM. LESS WATER IS NEEDED DURING MARCH, APRIL, MAY AND 5 (FROM DATE OF PLANT INSTALLATION). OCTOBER. 2. NATIVE PLANT COVER: � A. ACHIEVE 40% COVER OF NATIVE TREES, SHRUBS AND GROUNDCOVER IN TYPE 1 PLANTING z AREA BY YEAR 2. NATIVE VOLUNTEER SPECIES MAY COUNT TOWARDS THIS COVER CONSTRUCTION NOTES AND SPECIFICATIONS O STANDARD. THE RESTORATION PROFESSIONAL WILL MONITOR: U B. ACHIEVE 60% UNDERSTORY COVER OF NATIVE SAPLING TREES, SHRUBS AND GROUNDCOVER IN TYPE 1 PLANTING AREABY YEAR 3. NATIVE VOLUNTEER SPECIES MAY 1. ALL SITE PREPARATION. m 0� COUNT TOWARDS THIS COVER STANDARD. A. COIR LOG/STRAW WATTLE INSTALLATION. O C. ACHIEVE 80% UNDERSTORY COVER OF NATIVE SAPLING TREES, SHRUBS AND B. WEED REMOVAL. GROUNDCOVER IN TYPE 1 PLANTING AREA BY YEAR 5. NATIVE VOLUNTEER SPECIES MAY L.L COUNT TOWARDS THIS COVER STANDARD. C. SOIL PREPARATION. 3. SPECIES DIVERSITY: ESTABLISH AT LEAST TWO NATIVE TREE, SIX NATIVE SHRUB, AND TWO D. MULCH PLACEMENT. NATIVE GROUNDCOVER SPECIES BY YEAR 3 AND MAINTAIN THIS DIVERSITY THROUGH YEAR 5. 2. MITIGATION PLANTING ACTIVITIES. O z NATIVE VOLUNTEER SPECIES MAY COUNT TOWARDS THIS STANDARD. EXISTING VEGETATION A. PLANT MATERIAL DELIVERY INSPECTION. z O cn DOES NOT COUNT TOWARD THIS DIVERSITY STANDARD. > B. 100% PLANT INSTALLATION INSPECTION. w 4. INVASIVE COVER: AREAL COVER FOR ALL NON-NATIVE, INVASIVE AND NOXIOUS WEEDS WILL 0� NOT EXCEED 10% AT ANY YEAR DURING THE MONITORING PERIOD. INVASIVE PLANTS INCLUDE GENERAL WORK SEQUENCE 06 Z BUT ARE NOT LIMITED TO HIMALAYAN BLACKBERRY (RUBUS ARMENIACUS), CUT LEAF J ILIJ 0- BLACKBERRY (RUBUS LACINIATUS), KNOTWEEDS (POLYGONUM CUSPIDATUM AND OTHERS), SITE PREPARATION 1-- O z REED CANARYGRASS (PHALARIS ARUNDINACEA), CHERRY LAUREL (PRUNUS LAUROCERASUS), U)1--a_ o 1. INSTALL COIR LOG OR STRAW WATTLE PER PLANS. � ENGLISH HOLLY (ILEX AQUIFOLIUM), AND IVY SPECIES (HEDERA SPP.). m Fr < 2. MANUALLY CLEAR INVASIVE AND ORNAMENTAL VEGETATION FROM MITIGATION AREA DURING J) �z MONITORING METHODS SPRING AND/OR SUMMER MONTHS (I.E., AVOID CREATING EXPOSED SOIL CONDITIONS DURING THIS MONITORING PROGRAM IS DESIGNED TO TRACK THE SUCCESS OF THE MITIGATION SITE THE WINTER STORM SEASON). C) N OVER TIME AND TO MEASURE THE DEGREE TO WHICH THE SITE IS MEETING THE PERFORMANCE A. REMOVE INVASIVE SPECIES (I.E., HIMALAYAN BLACKBERRY, ENGLISH IVY), IN ACCORDANCE STANDARDS OUTLINED IN THE PRECEDING SECTION. WITH KING COUNTY NOXIOUS WEED BEST MANAGEMENT PRACTICES. FOR MORE o 0 INFORMATION: Uj AN AS -BUILT PLAN WILL BE PREPARED BY THE RESTORATION PROFESSIONAL PRIOR TO THE HTTPS://WWW.KINGCOUNTY.GOV/SERVICES/ENVIRONMENT/ANIMALS-AND-PLANTS/ o r BEGINNING OF THE MONITORING PERIOD. THE AS -BUILT PLAN WILL BE A MARK-UP OF THE NOXIOUS-WEEDS.ASPX. PLANTING PLANS INCLUDED IN THIS PLAN SET. THE AS -BUILT PLAN WILL DOCUMENT ANY DEPARTURES IN PLANT PLACEMENT OR OTHER COMPONENTS FROM THE PROPOSED PLAN. B. CUT UNDESIRABLE VEGETATION. LEAVE ROOTS INTACT TO MINIMIZE POTENTIAL IMPACTS SHEET SIZE: TO SLOPES ON ADJACENT PROPERTIES. ORIGINAL PLAN IS 22" x 34". MONITORING WILL TAKE PLACE ONCE ANNUALLY IN THE FALL FOR FIVE YEARS. YEAR-1 C. FLUSH -CUT ORNAMENTAL WOODY VEGETATION (E.G. ENGLISH HOLLY, NON-NATIVE APPLE SCALE ACCORDINGLY. MONITORING WILL COMMENCE IN THE FIRST FALL SUBSEQUENT TO INSTALLATION. w PROJECT MANAGER: GB z DESIGNED: RH LL DRAFTED: RH CHECKED: AMC, GB JOB NUMBER: m 191123 W MITIGATION PLAN NOTES SHEET NUMBER: z W7 OF 8w © 2020 -The Watershed Company o r 32 \ V 1321 /I I �36 1320 ,1 0 1 \\ 13191, \ ,ie 1318* PROPOSED DECK 1 � 1336\ ' \ I � 1 I 1335* / I 1337 I 17 � 1 TREE RETENTION AND REMOVAL PLAN SCALE 1:10 6 NOTES 1. TREE INVENTORY COMPLETED BY THE WATERSHED COMPANY ON JULY 1, 2020 (750 6TH STREET SOUTH; KIRKLAND, WA 98033; 425-9822-5242). SEE ARBORIST REPORT BY THE WATERSHED COMPANY (DATED AUGUST 17, 2020) FOR FURTHER DETAILS. 2. TREE NUMBERS WITH AN ASTERISK WERE NOT SURVEYED; LOCATION IS APPROXIMATE. 3. TREE PROTECTION FENCING IS SHOWN OFFSET FROM PROPOSED LIMITS OF DEVELOPMENT / CONSTRUCTION FOR VISUAL CLARITY PURPOSES ONLY. 4. SEE SHEET W8 FOR TREE RETENTION AND REMOVAL DETAILS. LEGEND EXISTING CONDITIONS PARCEL BOUNDARY DELINEATED WETLAND BOUNDARY APPROXIMATE WETLAND BOUNDARY DELINEATED OHWM STREAM BUFFER (35') SIGNIFICANT TREE PROPOSED CONDITIONS LIMITS OF DEVELOPMENT / CONSTRUCTION CRITICAL ROOT ZONE CRITICAL ROOT ZONE IMPACT TREE PROPOSED FOR REMOVAL (2) TREE PROTECTION FENCING A ws z 0 U OC (n Z O U OC O LL z w oc w 0' 5' 10, 20' 40' FVA i © 2020 - The Watershed Company 2 THE WATERSHED COMPANY 750 Sixth Street South Kirkland WA 98033 p 425.822.5242 www.watershedco.com Science & Design i Z U M Q LL J Q W W . o ~ o rn Z � z� < c) < O_cf)N3: �I C/) 0 C D �1 Q Q L �LLN W Q — U 0 U) 0� w LULU><<o � � X W OC Q r IL Q n W W rr W z O w �06 v J z J Q z O m U 0 J)P: o 2 O N H N_ Q 04 Q N O T 0 z T SHEET SIZE: ORIGINAL PLAN IS 22" x 34". SCALE ACCORDINGLY. PROJECT MANAGER: GB w z DESIGNED: RH U- DRAFTED: RH CHECKED: AMC, GB JOB NUMBER: m 191123 W z SHEET NUMBER: a W/ OF 8 a 0 TREE RETENTION AND REMOVAL TABLE TAG # TREE NAME LLIp '~ 2 m p � m _ O z u� .-. LL = W = LL p a oc z0 ~ O v N p W F_ O v O LLIp =a O v a W = cc O a u N m O LL p J LLI O O a = LU a oc 1301 Alnus rubra (Red alder) 1 11.5 60 15 2 1.5 Y - 1302 Alnus rubra (Red alder) 1 10.8 60 12 2 1.5 Y - 1303 Alnus rubra (Red alder) 1 13.6 60 15 2 2.0 Y - 1304 Alnus rubra (Red alder) 1 14.5 60 15 2 2.0 - - 1305 Alnus rubra (Red alder) 1 9.8 60 10 4 - Y - 1306 Alnus rubra (Red alder) 1 11.6 60 15 3 1.5 Y - 1307 Alnus rubra (Red alder) 1 11.8 65 15 2 1.5 Y - 1308 Alnus rubra (Red alder) 1 10.7 25 5 4 - Y Y 1309 Alnus rubra (Red alder) 1 8.9 50 12 4 - Y Y 1310 Alnus rubra (Red alder) 1 9.1 55 15 4 - - - 1312 Alnus rubra (Red alder) 1 9.0 50 10 2 1.5 - - 1313 Alnus rubra (Red alder) 1 16.0 55 20 2 2.0 - - 1314 Alnus rubra (Red alder) 1 14.3 65 15 2 2.0 - - 1315 Alnus rubra (Red alder) 2 16.4 65 25 3 2.0 - - 1316 Acer macrophyllum (Bigleaf maple) 1 7.7 12 5 5 - - - 1317 Acer macrophyllum (Bigleaf maple) 1 6.7 12 5 5 - - - 1318 Acer macrophyllum (Bigleaf maple) 1 7.9 20 10 5 - - - 1321 Acer macrophyllum (Bigleaf maple) 3 30.3 25 12 5 - - - 1322 Acer macrophyllum (Bigleaf maple) 1 31.2 70 30 2 3.0 - - 1323 Alnus rubra (Red alder) 1 6.2 50 15 4 - - - 1324 Alnus rubra (Red alder) 1 16.4 70 15 2 2.0 - - 1325 Alnus rubra (Red alder) 1 15.5 70 15 2 2.0 - - 1326 Acer macrophyllum (Bigleaf maple) 3 21.4 70 15 4 - - - 1327 Acer macrophyllum (Bigleaf maple) 3 22.1 60 15 4 - - - 1328 Acer macrophyllum (Bigleaf maple) 1 55.1 75 30 3 3.0 - - 1329 Alnus rubra (Red alder) 1 23.0 75 20 2 2.5 - - 1330 Alnus rubra (Red alder) 1 19.5 70 20 3 2.5 - - 1331 Tsuga heterophylla (Western hemlock) 1 19.8 75 15 3 2.5 - - 1332 Alnus rubra (Red alder) 1 18.0 80 20 3 2.0 - - 1333 Acer macrophyllum (Bigleaf maple) 1 20.0 70 15 4 - - - 1334 Tsuga heterophylla (Western hemlock) 1 20.6 80 15 3 2.5 - - 1335 Tsuga heterophylla (Western hemlock) 1 24.6 80 15 3 3.0 - - 1336 Acer macrophyllum (Bigleaf maple) 2 15.5 65 20 4 - - - 1337 Alnus rubra (Red alder) 1 20.9 75 15 3 2.5 - - 1338 Alnus rubra (Red alder) 1 23.6 70 20 3 2.5 - - 1339 Alnus rubra (Red alder) 1 13.7 75 15 2 2.0 - - 1340 Acer macrophyllum (Bigleaf maple) 1 9.3 8 8 5 - - - NOTES 1. SEE SHEET W7 FOR TREE RETENTION AND REMOVAL PLAN. 2. IMPACTS ARE NOT ANTICIPATED WITHIN CRITICAL ROOT ZONES OF SIGNIFICANT TREES LOCATED OFF -PARCEL. TREE RETENTION AND REMOVAL DETAILS FWMC 19.120.160 TREE AND VEGETATION PROTECTION DURING CONSTRUCTION (1) NO CLEARING SHALL BE ALLOWED ON A PROPOSED DEVELOPMENT SITE UNTIL THE TREE RETENTION AND LANDSCAPE PLANS HAVE BEEN APPROVED BY THE CITY OF FEDERAL WAY. (2) A NO DISTURBANCE AREA SHALL BE ESTABLISHED FOR EACH TREE TO BE PROTECTED. THE NO DISTURBANCE ZONE SHALL BE EQUAL TO THE CRITICAL ROOT ZONE WHICH IS DEFINED AS 12 INCHES RADIUS FOR EVERY ONE INCH OF TREE DIAMETER MEASURED AT FOUR AND ONE-HALF FEET ABOVE GROUND. ANY OTHER NO DISTURBANCE AREA PROPOSED BY THE APPLICANT SHALL BE DETERMINED BY A QUALIFIED ARBORIST AND SUBJECT TO REVIEW AND APPROVAL BY THE DIRECTOR. (3) THE NO DISTURBANCE ZONE SHALL BE IDENTIFIED DURING THE CONSTRUCTION STAGE WITH: (a) A TEMPORARY FIVE-FOOT CHAIN -LINK FENCE; AND (b) TREE PROTECTION SIGNAGE ATTACHED TO THE FENCE WHICH READS "TREE PROTECTION FENCE - NO SOIL DISTURBANCE, PARKING, STORAGE, DUMPING, OR BURNING OF MATERIALS IS ALLOWED WITHIN THE TREE PROTECTION FENCE." (4) NO SOIL DISTURBANCE, PARKING, STORAGE, DUMPING, BURNING OF MATERIALS, IMPERVIOUS SURFACES, FILL, EXCAVATION, OR STORAGE OF CONSTRUCTION MATERIALS SHALL BE PERMITTED WITHIN THE NO DISTURBANCE AREA. (5) IF THE GRADE LEVEL AROUND THE TREE IS TO BE RAISED BY MORE THAN ONE FOOT, A ROCK WELL SHALL BE CONSTRUCTED. THE INSIDE DIAMETER OF THE ROCK WELL SHALL BE EQUAL TO THE DIAMETER OF THE TREE TRUNK PLUS 10 FEET. PROPER DRAINAGE, AND IRRIGATION IF NECESSARY, SHALL BE PROVIDED IN ALL ROCK WELLS. (6) THE GRADE LEVEL SHALL NOT BE LOWERED WITHIN THE LARGER OF THE DRIP LINE OF THE TREE(S) OR THE CRITICAL ROOT ZONE OF THE TREE(S). (7) NO TRENCHING IS ALLOWED IN ANY CRITICAL TREE ROOT ZONE AREAS. (8) NO INSTALLATION OF ANY IMPERVIOUS SURFACES IS ALLOWED IN CRITICAL ROOT ZONES. WHERE ROAD OR SIDEWALK SURFACES ARE NEEDED WITHIN CRITICAL ROOT ZONES, UNMORTARED POROUS PAVERS OR FLAGSTONE (RATHER THAN CONCRETE OR ASPHALT) MAY BE USED. BOARDWALKS OR BRIDGING MAY SPAN ROOT ZONES WITHOUT HARMING THE TREE ROOTS. (9) TREE PROTECTION AREAS (I.E., CRITICAL ROOT ZONE) MUST BE PREPARED TO BETTER WITHSTAND THE STRESSES OF THE CONSTRUCTION PHASE BY, IF NECESSARY, FERTILIZING, PRUNING, AND MULCHING AROUND THEM WELL IN ADVANCE OF BEGINNING ANY CONSTRUCTION ACTIVITIES. (10) ALTERNATIVE PROTECTION METHODS MAY BE USED IF ACCEPTED BY THE DIRECTOR TO PROVIDE EQUAL OR GREATER TREE PROTECTION. (11) ENCROACHMENT INTO THE NO DISTURBANCE AREA MAY BE ALLOWED WHERE THE DIRECTOR DETERMINES ENCROACHMENT WOULD NOT BE DETRIMENTAL TO THE HEALTH OF THE TREE. CRITICAL ROOT ZONE OR OTHER LIMIT OF TREE PROTECTION AREA. SEE SHEET W7 FOR FENCE ALIGNMENT. 70d 8.5" x 11" SIGN LAMINATED IN PLASTIC SPACED EVERY 50' ALONG FENCE. TREE PROTECTION FENCING NOTES: 1. NO PRUNING SHALL BE PERFORMED UNLESS UNDER THE DIRECTION OF AN ARBORIST. 2. NO EQUIPMENT SHALL BE STORED OR OPERATED INSIDE THE PROTECTIVE FENCING INCLUDING DURING FENCE INSTALLATION AND REMOVAL. 3. NO STORAGE OF MATERIALS SHALL OCCUR INSIDE THE PROTECTIVE FENCING. 4. UNAUTHORIZED ACTIVITIES IN TREE PROTECTION AREA MAY REQUIRE EVALUATION BY PRIVATE ARBORIST TO IDENTIFY IMPACTS AND MITIGATION REQUIRED. 5. EXPOSED ROOTS: FOR ROOTS GREATER THAN 1" DAMAGED DURING CONSTRUCTION, MAKE A CLEAN, STRAIGHT CUT TO REMOVE DAMAGED PORTION AND INFORM CITY ARBORIST. TREE PROTECTION FENCE - CHAIN -LINK FENCING, STEEL POSTS INSTALLED AT 8' O.C. 5" THICK LAYER OF MULCH. MAINTAIN EXISTING GRADE WITH THE TREE PROTECTION FENCE UNLESS OTHERWISE INDICATED ON THE PLANS. Scale: NTS z 0 0� 0 LL 0 Z 1 W U) W © 2020 - The Watershed Company THE WATERSHED COMPANY 750 Sixth Street South Kirkland WA 98033 p 425.822.5242 www.watershedco.com Science & Design Z U M Q LL JQL� 00 o 1--I w O d Z0 � Z� < c) < O�C/) N 3: L 0 CO J �LLN L Q - U 0 U L w LU > C) O� X L Q r LL L m0� W z 0 w 06 z J J H O a �o m U 0 U H o 0 N W NO a Q N O T O z T SHEET SIZE: ORIGINAL PLAN IS 22" x 34". SCALE ACCORDINGLY. PROJECT MANAGER: GB w z DESIGNED: RH uj DRAFTED: RH CHECKED: AMC, GB JOB NUMBER: ca m 191123 W z SHEET NUMBER: a W8 OF 8W 0 Appendix 6 WETLAND AND STREAM DELINEATION REPORT 2 THE WATERSHED COMPANY January 6, 2020 Revised: October 29, 2020 Second Revision: April 13, 2020 Stan Afichuk 29328 1st Ave South Federal Way, WA 98003 via email: stan@greenbuilddev.com 206-708-0065 Re: Afichuk Property, Stream Delineation Report The Watershed Company Reference Number: 191123 Dear Stan: S C I E N C E & D E 5 1 G N On December 11, 2019, Ecologists Logan Dougherty and Grace Brennan visited the 0.43-acre property located at 1XX S 293rd Street (parcel 7202500080) in Federal Way, Washington, to delineate jurisdictional streams. On February 24, 2020, Grace Brennan met on -site with the client and Landeau Associates to review the findings of the original letter. This letter summarizes the findings of the studies and details applicable federal, state, and local regulations. The following documents are enclosed: • Delineation Sketch • Wetland Determination Data Forms • Wetland Rating Form and Figures Findings Summary One stream (Stream A) is located in the study area. Stream A is classified as a non -fish bearing, seasonal stream (Type Ns). The City of Federal Way requires a standard 35-foot buffer for Stream A. One Wetland (Wetland A) is located adjacent to Stream A. Wetland A is a Category III wetland with a 150-foot buffer. Study Area The study area for this project is defined as King County parcel 7202500080, totaling 0.43 acres. 750 Sixth Street South I Kirkland, WA 98033 P 425.822.5242 If 425.827.8136 1 watershedco.com Delineation Report Afichuk January 2020 Revised October 2020 Page 2 Methods Public -domain information on the subject properties was reviewed for this delineation study. Resources and review findings are presented in Table 1 of the "Findings" section of this letter. The study area was evaluated for streams based on the presence or absence of an ordinary high water mark (OHWM) as defined by Section 404 of the Clean Water Act, the Washington Administrative Code (WAC) 220-660-030, and the Revised Code of Washington (RCW) 90.58.030. Characterization of climatic conditions for precipitation in the Wetland Determination Data Forms were determined using the WETS table methodology (USDA, NRCS 2015). The "Seattle Tacoma Intl AP" station from 1981-2010 was used as a source for precipitation data (http://agacis.rcc-acis.org/). The WETS table methodology uses climate data from the three months prior to the site visit month to determine if normal conditions are present in the study area region. Findings The study area is within in the "Lower Puget Sound - DM/Fed Way" sub -basin of the Duwamish - Green Watershed (WRIA 9); Section 05 of Township 21 North, Range 04 East of the Public Land Survey System. A ravine extends northwest from the southeast corner of the study area, exiting the study area at its northern boundary. Stream A and Wetland A are located within this ravine. The study area totals 0.43 acres in size. Parcel 7202500070 (south) has been recently developed with a single-family home. Both the east and the west sides of the parcel slope downward toward Stream A and the ravine. The west side contains a small terrace with reed canarygrass and additional steep slopes that slope north towards Puget Sound. Reviewed public -domain information for the site is summarized below (Table 1). Public -domain information was reviewed within a 500-foot vicinity to the study area. Delineation Report Afichuk January 2020 Revised October 2020 Page 3 Table 1. Summary of online mapping and inventory resources. Resource Summary USDA NRCS: Web Soil Survey Alderwood and Kitsap soils, very steep. USFWS: NWI Wetland Mapper No NWI features mapped on subject property. Tributary to Cold Creek mapped approx. 400 feet east of subject property. WDFW: PHS on the Web WDFW: SalmonScape WA-DNR: Forest Practices Activity Mapping Tool King County iMap: Federal Way Critical Area Maps: WETS Climatic Condition Wetlands "Biodiversity areas and corridor" mapped east -adjacent to subject parcel. Fish -bearing stream (tributary to Cold Creek) mapped approx. 375 feet east of subject property. Coho salmon and coastal cutthroat trout mapped in stream (tributary to Cold Creek) approx. 350 feet east of subject property. Type U stream (tributary to Cold Creek) mapped approx. 350 feet east of subject property. Parcel mapped within erosion hazard area. Cold Creek mapped approx. 340 feet northeast of subject property. Parcel mapped within erosion hazard area and landslide hazard area. No stream mapped on subject property; Cold Creek mapped to the east. Normal. One wetland (Wetland A) was delineated and flagged in the study area. Wetland A is summarized in Table 2. Delineation Report Afichuk January 2020 Revised October 2020 Page 4 Table 2. Wetland A Assessment Summary. THE WATERSHED 2 WETLAND A — Assessment Summary COMPANY Location: Along both sides of Stream A, extending through ravine that runs through site. WRIA / Sub -basin: Duwamish — Green Watershed (WRIA 9) / Lower Puget Sound — DM/Fed Way sub -basin 2014 Western WA Category III Ecology Rating: Buffer Width and Buffer 150 ft. Setback: 5 ft. Wetland Size: Approx. 2,300 ftz Cowardin Palustrine scrub -shrub, t,. Classification(s): palustrine emergent HGM Classification(s): Slope/Riverine Wetland Data Sheet(s): DP-2 Upland Data Sheet (s): DP-3 Flag Color: Pink and black striped Flag Numbers: A-1 to A-9 Tree stratum: Red alder Vegetation Shrub stratum: Salmonberry, Himalayan blackberry Herb stratum: Giant horsetail, American speedwell Soil survey: Alderwood and Kitsap soils, very steep Soils Field data: Depleted matrix Source: Groundwater seeps, overbank flooding Hydrology Field data: High water table, saturation Wetland Functions Improving Hydrologic Habitat Water Quality Site Potential H M L H M L H M L Landscape Potential H M L H M L H M L Value H M L H M L H M L TOTAL Score Based on Ratings 6 8 6 20 Description and Comments Wetland A is a slope wetland with a small riverine component. Wetland A sits in the narrow ravine Stream A runs through. A majority of the wetland is fed through visible groundwater seeps. Areas of the wetland extend upslope from Stream A on both the east and west side of Stream A. Delineation Report Afichuk January 2020 Revised October 2020 Page 5 Streams Stream A flows along a steep gradient through Wetland A, averaging three to four feet in width. The substrate is dominated by muck with intermittent sections of cobble. A portion of the stream flow, beginning at WMA-4L and WMA-4R, is carried in a black 12" diameter HDPE pipe that extends to the property line. This pipe appears some type of erosion control device whose origins are unknown but may be related to the downstream mobile home park property. The pipe a portion of the stream flow from the daylighted stream segment above; however, there is still evidence of water flow beneath the pipe. Stream flow enters a catch basin and drain (Photo 1) at the northern property line. Both the stream and wetland are supplemented by groundwater seeps, and at the time of the site visit water was flowing through the entirety of Stream A. Stream A is likely seasonally flowing and flows along a slope greater than twenty percent; therefore, Stream A does not contain suitable fish habitat. Non -wetlands Non -wetland areas are generally upslope (east and west) of Wetland A and do not meet all criteria for hydrophytic vegetation, hydric soils, or wetland hydrology. The east slope portion of the parcel is dominated by western hemlock and sword fern. The western portion of the parcel is dominated by reed canarygrass and Himalayan blackberry in the upper terrace and red alder, Osoberry, salmonberry, sword fern, and trailing blackberry in the lower slope area (Photos 2 and 3). Local Regulations Critical areas in Federal Way are regulated by Federal Way Revised Code (FWRC) Chapter 19.145, Environmentally Critical Areas. According to the code, wetlands are rated as one of four categories based on the Rating System. Under the Rating System, Wetland A was rated as Category III wetland with a habitat score of 6 points, and therefore requires a 150-foot buffer (FWRC 19.145.420[2]). Stream buffers are determined based on the stream type classification. The Stream A/Wetland A system meets the criteria of a Type Ns water. Type Ns streams require a buffer of 35 feet (FWRC 19.145.270[1]). Federal Way requires a 5-foot building setback from the edges of all critical area buffers (FWRC 19.145.160). Building setbacks may contain landscaping, building overhangs, and fences or railings six feet or less in height. Delineation Report Afichuk January 2020 Revised October 2020 Page 6 Critical Area Buffer Reduction Federal Way allows for buffers of all categories of wetlands to be reduced by 25% if buffer enhancement is provided, resulting in no loss of buffer function (FWRC 19.45.445[6]). Wetland A's buffer could therefore be reduced to 112.5 feet and Stream A's buffer to 26.25 feet. Typically, this entails the removal of invasive species, dense planting of native plants, and a 5-year monitoring period. Based on the location of the wetland boundaries, it does not appear that a 25% reduction will be adequate to allow for development on the subject property. Wetland and aquatic area buffers may also be modified through buffer averaging, in accordance with FWRC 19.145.440(5). Buffer averaging may be allowed if the total buffer area is equivalent to the area before averaging, the averaged buffer is contiguous with the standard buffer, and "the ecological structure and function of the buffer after averaging is equivalent to or greater than the structure and function before averaging. In some circumstances, buffer averaging may be accompanied by buffer enhancement in order to balance ecological functions. Averaged buffers cannot be reduced to less than 75% of the standard buffer width in any location. Due to the extent of buffers on the property, buffer averaging does not appear to be a feasible option to allow for development. Reasonable Use Exception If the strict implementation of the critical area regulations would deprive a landowner all reasonable use of their parcel, the provisions may be modified or waived on a case -by -case basis (FWRC 19.145.090). An applicant must demonstrate that impacts to the critical area have been minimized to the greatest extent possible and that no feasible on -site alternatives to their proposal are possible. This provision typically allows for the development of one single-family residence per parcel. Pursuing a reasonable use exception appears to be the only feasible option for development for this site based on buffer encumbrance. State and Federal Regulations Federal Agencies Most wetlands and streams are regulated by the Corps under Section 404 of the Clean Water Act. Any proposed filling or other direct impacts to Waters of the U.S., including wetlands (except isolated wetlands), would require notification and permits from the Corps. Wetland A would not be considered isolated. Unavoidable impacts to jurisdictional wetlands are typically required to be compensated through implementation of an approved mitigation plan. If activities requiring a Corps permits are proposed, a Joint Aquatic Resource Permit Application (DARPA) could be submitted to obtain authorization. Delineation Report Afichuk January 2020 Revised October 2020 Page 7 Federally permitted actions that could affect endangered species may also require a biological assessment study and consultation with the U.S. Fish and Wildlife Service and/or the National Marine Fisheries Service. Compliance with the Endangered Species Act must be demonstrated for activities within jurisdictional wetlands and the 100-year floodplain. Application for Corps permits may also require an individual 401 Water Quality Certification and Coastal Zone Management Consistency determination from Ecology and a cultural resource study in accordance with Section 106 of the National Historic Preservation Act. Washington Department of Ecology (Ecology) Similar to the Corps, Ecology, under Section 401 of the Clean Water Act, is charged with reviewing, conditioning, and approving or denying certain federally permitted actions that result in discharges to state waters. However, Ecology review under the Clean Water Act would only become necessary if a Section 404 permit from the Corps was issued. However, Ecology also regulates wetlands, including isolated wetlands, under the Washington Pollution Prevention and Control Act, but only if direct wetland impacts are proposed. Therefore, if filling activities are avoided, authorization from Ecology would not be needed. If filling is proposed, a JARPA may be also be submitted to Ecology in order to obtain a Section 401 Water Quality Certification and Coastal Zone Management Consistency Determination. Ecology permits are either issued concurrently with the Corps permit or within 90 days following the Corps permit. In general, neither the Corps nor Ecology regulates wetland and stream buffers, unless direct impacts are proposed. When direct impacts are proposed, mitigated wetlands and streams may be required to employ buffers based on Corps and Ecology joint regulatory guidance. Washington Department of Fish and Wildlife (WDFW) Chapter 77.55 of the RCW (the Hydraulic Code) gives WDFW the authority to review, condition, and approve or deny "any construction activity that will use, divert, obstruct, or change the bed or flow of state waters." This provision includes any in -water work, installation of bridges, docks and other overwater structures and can sometimes include stormwater discharge to state waters. If a project meets regulatory requirements, WDFW will issue a Hydraulic Project Approval (HPA). Through issuance of an HPA, WDFW can also restrict activities to a particular timeframe. Work is typically restricted to late summer and early fall. However, WDFW has in the past allowed crossings that don't involve in -stream work to occur at any time during the year. Delineation Report Afichuk January 2020 Revised October 2020 Page 8 Disclaimer The information contained in this letter is based on the application of technical guidelines currently accepted as the best available science and in conjunction with the manuals and criteria referenced above. All discussions, conclusions and recommendations reflect the best professional judgment of the author(s) and are based upon information available at the time the study was conducted. All work was completed within the constraints of budget, scope, and timing. The findings of this report are subject to verification and agreement by the appropriate local, state and federal regulatory authorities. No other warranty, expressed or implied, is made. Please call if you have any questions or if we can provide you with any additional information. Sincerely, Grace Brennan Ecologist Enclosures Delineation Report Afichuk January 2020 Revised October 2020 Page 9 References Anderson, P.S. et al. 2016. Determining the Ordinary High Water Mark for Shoreline Management Act Compliance in Washington State. (Publication #16-06-029). Olympia, WA: Shorelands and Environmental Assistance Program, Washington Department of Ecology. Department of Ecology (Ecology). 2018. July 2018 Modifications for Habitat Score Ranges. Modified from Wetland Guidance for CAO Updates, Western Washington Version. (Publication #16-06-001). Accessed 8/16/18: https:Hfortress.wa.gov/ecy/publications/parts/1606001partl.pdf. Environmental Laboratory. 1987. "Corps of Engineers Wetlands Delineation Manual," Technical Report Y-87-1, U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS. Hruby, T. 2014. Washington State Wetland Rating System for Western Washington: 2014 Update. (Publication #14-06-029). Olympia, WA: Washington Department of Ecology. Lichvar, R.W. and S. M. McColley. 2008. A Guide to Ordinary High Water Mark (OHWM) Delineation for Non -Perennial Streams in the Western Mountains, Valleys, and Coast Region of the United States. ERDC/CRREL TR-14-13. Hanover, NH: U.S. Army Engineer Research and Development Center. U.S. Army Corps of Engineers. 2010. Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region (Version 2.0). ed. J. S. Wakely, R. W. Lichvar, and C. V. Noble. ERDC/EL TR-10-3. Vicksburg, MS: U.S. Army Engineer Research and Development Center. U.S. Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS). 2015. National Engineering Handbook, Part 650 Engineering Field Handbook, Chapter 19 Hydrology Tools for Wetland Identification and Analysis. ed. R. A. Weber. 210-VI-NEH, Amend. 75. Washington, DC. _; A•!; V, g J ' sffF i >at Delineation Report Afichuk January 2020 Revised October 2020 Page 12 Additional Figures Figure 1. HGM classes of Wetland A. 2 WATERSHED WETLAND DETERMINATION DATA FORM — Western Mountains, Valleys, and Coast Region DP - 1 Project/Site: 1XX S 293rd Street, Federal Way; parcel no. 7202500080 City/County: Federal Way Sampling date: 12/11/19 Applicant/Owner: S. Afichuk State: WA Sampling Point: DP-1 Investigator(s): L. Dougherty, G. Brennan Section, Township, Range: 05, 21N, 04E Landform (hillslope, terrace, etc): Hillslope Local relief (concave, convex, none): None Slope (%): 80 Subregion (LRR): A Lat: - Long: - Datum: - Soil Map Unit Name: Alderwood and Kitsap soils, very steep NWI classification: None Are climatic / hydrologic conditions on the site typical for this time of year? ❑X Yes ❑ No (If no, explain in remarks.) Are Vegetation ❑, Soil ❑, or Hydrology ❑ significantly disturbed? Are "Normal Circumstances" present on the site? © Yes ❑ No Are Vegetation ❑, Soil ❑, or Hydrology ❑ naturally problematic? (If needed, explain any answers in Remarks.) SUMMARY OF FINDINGS - Attach site map showing sampling point locations, transects, important features, etc. Hydrophytic Vegetation Present? Yes ® No ❑ Hydric Soils Present? Yes ❑x No ❑ Is the Sampled Area Yes ❑ No within a Wetland? Wetland Hydrology Present? Yes ❑ No ❑X Remarks: Recorded in potential wetland area near NW property corner. Climatic conditions considered "normal' per WETS table methodology. VEGETATION - Use scientific names of plants. Tree Stratum (Plot size: 5-m diameter) 1. Alnus rubra Absolute % Cover 70 Dominant Indicator Species? Status Y FAC Dominance Test worksheet: Number of Dominant Species 4 that are OBL, FACW, or FAC: (A) Total Number of Dominant 4 Species Across all Strata: (B) Percent of Dominant Species 100 that are OBL, FACW, or FAC: A/B 2• 3. 4. Sapling/Shrub Stratum (Plot size: 3-m diameter) 1. Rubus s ectabilis 70 60 = Total Cover Y FAC Prevalence Index worksheet: Total % Cover of: Multiply by: OBL species x 1 = FACW species x 2 = FAC species x 3 = FACU species x 4 = UPL species x 5 = Column Totals: (A) (B) Prevalence Index = B/A = 2. 3. 4. 5. 60 = Total Cover Herb Stratum (Plot size: 1-m diameter) 1. Scir us microcar us 50 Y OBL 2. Tolmiea menziesii 60 Y FAC 3. Hydrophytic Vegetation Indicators: ❑ 1 - Rapid Test for Hydrophytic Vegetation ❑X 2 - Dominance Test is > 50% ❑ 3 - Prevalence Index is !- 3.0' ❑ 4 - Morphological Adaptations' (Provide supporting data in Remarks or on a separate sheet) ❑ 5 - Wetland Non -Vascular Plants' ❑ Problematic Hydrophytic Vegetation' (Explain) 'Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic. 4. 5. 6. 7. 8. 9. 10. 11. Woody Vine Stratum (Plot size: 3-m diameter) 1. 110 = Total Cover Hydrophytic Vegetation Yes ® No ❑ Present? 2. 0 = Total Cover % Bare Ground in Herb Stratum: 0 Remarks: US Army Corps of Engineers Western Mountains, Valleys, and Coast - Version 2.0 SOIL Sampling Point: DP-1 Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.) Depth Matrix Redox Features inches Color moist % Color moist % Type' Loc' Texture Remarks 0-8 2.5Y 3/1 100 Clay loam 8-15 2.5Y 5/2 65 7.5YR 5/8 35 C M, PL Clay loam 15-20 5Y 5/1 65 7.5YR 5/8 35 C M Clay loam 'Type: C=Concentration, D=De letion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. 2Loc: PL=Pore Lining, M=Matrix. Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) ❑ Histosol (Al) ❑ Sandy Redox (S5) ❑ Histic Epipedon (A2) ❑ Stripped Matrix (S6) ❑ Black Histic (A3) ❑ Loamy Mucky Mineral (F1) (except MLRA 1) ❑ Hydrogen Sulfide (A4) ❑ Loamy Gleyed Matrix (F2) ❑ Depleted Below Dark Surface (Al 1) 0 Depleted Matrix (F3) ❑ Thick Dark Surface (Al2) ❑ Redox Dark Surface (F6) ❑ Sandy Mucky Mineral (S1) ❑ Depleted Dark Surface (F7) ❑ Sandy Gleyed Matrix (S4) ❑ Redox Depressions (F8) Indicators for Problematic Hydric Soils3: ❑ 2cm Muck (A10) ❑ Red Parent Material (TF2) ❑ Very Shallow Dark Surface (TF12) ❑ Other (Explain in Remarks) 3Indicators of hydrophytic vegetation and wetland hydrology must be present, unless disturbed or problematic. Restrictive Layer (if present): Type: Hydric soil present? Yes ® No El Depth (inches): Remarks: HYDROLOGY Wetland Hydrology Indicators: Primary Indicators (minimum of one required: check all that apply) Secondary Indicators (2 or more required) ❑ Surface water (Al) El�nWpr Rtamne -eaves (except MLRA , 2, en ❑ Water -Stained Leaves (139) (MLRA 1, ❑ High Water Table (A2) & " 2, 4A & 413) ❑ Saturation (A3) ❑ Salt Crust (1311) ❑ Drainage Patterns (610) ❑ Water Marks (61) ❑ Aquatic Invertebrates (1313) ❑ Dry -Season Water Table (C2) ❑ Sediment Deposits (62) ❑ Hydrogen Sulfide Odor (C1) ❑ Saturation Visible on Aerial Imagery (C9) ❑ Drift Deposits (63) ❑ Oxidized Rhizospheres along Living Roots (C3) ❑ Geomorphic Position (D2) ❑ Algal Mat or Crust (134) ❑ Presence of Reduced Iron (C4) ❑ Shallow Aquitard (D3) ❑ Iron Deposits (135) ❑ Recent Iron Reduction in Tilled Soils (C6) 0 FAC-Neutral Test (D5) ❑ Surface Soil Cracks (66) ❑ Stunted or Stressed Plants (D1) (LRR A) ❑ Raised Ant Mounds (D6) (LRR A) ❑ Inundation Visible on Aerial Imagery (67) ❑ Other (explain in remarks) ❑ Frost -Heave Hummocks ❑ Sparsely Vegetated Concave Surface (138) Field Observations: Surface Water Present? Yes ❑ No 0 Depth (in): Water Table Present? Yes ElNo 0 Depth (in): Wetland Hydrology Present? Yes El No Saturation Present? Yes ❑ No 0 Depth (in): includes capillary fringe) Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available: Remarks: Moist, not saturated. US Army Corps of Engineers Western Mountains, Valleys, and Coast - Version 2.0 2 WATERSHED WETLAND DETERMINATION DATA FORM — Western Mountains, Valleys, and Coast Region DP _ 2 Project/Site: 1XX S 293rd Street, Federal Way; parcel no. 7202500080 City/County: Federal Way Sampling date: 12/11/19 Applicant/Owner: S. Afichuk State: WA Sampling Point: DP-2 Investigator(s): L. Dougherty, G. Brennan Section, Township, Range: 05, 21N, 04E Landform (hillslope, terrace, etc): Hillslope Local relief (concave, convex, none): None Slope (%): 10 Subregion (LRR): A Lat: - Long: - Datum: - Soil Map Unit Name: Alderwood and Kitsap soils, very steep NWI classification: None Are climatic / hydrologic conditions on the site typical for this time of year? ❑X Yes ❑ No (If no, explain in remarks.) Are Vegetation ❑, Soil ❑, or Hydrology ❑ significantly disturbed? Are "Normal Circumstances" present on the site? © Yes ❑ No Are Vegetation ❑, Soil ❑, or Hydrology ❑ naturally problematic? (If needed, explain any answers in Remarks.) SUMMARY OF FINDINGS - Attach site map showing sampling point locations, transects, important features, etc. Hydrophytic Vegetation Present? Yes ® No ❑ Hydric Soils Present? Yes ❑x No ❑ Is the Sampled Area Yes ® No ❑ within a Wetland? Wetland Hydrology Present? Yes ❑x No ❑ Remarks: Wetland A in -pit. Climatic conditions considered "normal' per WETS table methodology. VEGETATION - Use scientific names of plants. Tree Stratum (Plot size: 5-m diameter) 1. Alnus rubra rooted outside of unit Absolute % Cover 70 Dominant Indicator Species? Status FAC Dominance Test worksheet: Number of Dominant Species 3 that are OBL, FACW, or FAC: (A) Total Number of Dominant 3 Species Across all Strata: (B) Percent of Dominant Species 100 that are OBL, FACW, or FAC: A/B 2• 3. 4. Sapling/Shrub Stratum (Plot size: 3-m diameter) 1. Rubus s ectabilis 70 30 = Total Cover Y FAC Prevalence Index worksheet: Total % Cover of: Multiply by: OBL species x 1 = FACW species x 2 = FAC species x 3 = FACU species x 4 = UPL species x 5 = Column Totals: (A) (B) Prevalence Index = B/A = 2. 3. 4. 5. 30 = Total Cover Herb Stratum (Plot size: 1-m diameter) 1. Tolmiea menziesii 15 Y FAC 2. Ath rium c closorum wilted fronds 15 Y FAC 3. Hydrophytic Vegetation Indicators: ❑ 1 - Rapid Test for Hydrophytic Vegetation ❑X 2 - Dominance Test is > 50% ❑ 3 - Prevalence Index is !- 3.0' ❑ 4 - Morphological Adaptations' (Provide supporting data in Remarks or on a separate sheet) ❑ 5 - Wetland Non -Vascular Plants' ❑ Problematic Hydrophytic Vegetation' (Explain) 'Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic. 4. 5. 6. 7. 8. 9. 10. 11. Woody Vine Stratum (Plot size: 3-m diameter) 1. 30 = Total Cover Hydrophytic Vegetation Yes ® No ❑ Present? 2. 0 = Total Cover % Bare Ground in Herb Stratum: 70 Remarks: US Army Corps of Engineers Western Mountains, Valleys, and Coast - Version 2.0 SOIL Sampling Point: DP-2 Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.) Depth Matrix Redox Features inches Color moist % Color moist % Type' LoC2 Texture Remarks 0-9 10YR 4/1 95 7.5YR 3/4 5 C M Clay loam 9-16 10YR 3/1 98 7.5YR 3/4 2 C M Clay loam 'Type: C=Concentration, D=De letion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. 2Loc: PL=Pore Lining, M=Matrix. Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) ❑ Histosol (Al) ❑ Sandy Redox (S5) ❑ Histic Epipedon (A2) ❑ Stripped Matrix (S6) ❑ Black Histic (A3) ❑ Loamy Mucky Mineral (F1) (except MLRA 1) ❑ Hydrogen Sulfide (A4) ❑ Loamy Gleyed Matrix (F2) ❑ Depleted Below Dark Surface (Al 1) ❑x Depleted Matrix (F3) ❑ Thick Dark Surface (Al2) ❑ Redox Dark Surface (F6) ❑ Sandy Mucky Mineral (S1) ❑ Depleted Dark Surface (F7) ❑ Sandy Gleyed Matrix (S4) ❑ Redox Depressions (F8) Indicators for Problematic Hydric Soils': ❑ 2cm Muck (A10) ❑ Red Parent Material (TF2) ❑ Very Shallow Dark Surface (TF12) ❑ Other (Explain in Remarks) ' Indicators of hydrophytic vegetation and wetland hydrology must be present, unless disturbed or problematic. Restrictive Layer (if present): Type: Hydric soil present? Yes ® No El Depth (inches): Remarks: HYDROLOGY Wetland Hydrology Indicators: Primary Indicators (minimum of one required: check all that apply) Secondary Indicators (2 or more required) ❑ Surface water (Al) El�nWpr Rtamne -eaves (except MLRA , 2, nn ❑ Water -Stained Leaves (139) (MLRA 1, O High Water Table (A2) & " 2, 4A & 413) O Saturation (A3) ❑ Salt Crust (1311) ❑ Drainage Patterns (610) ❑ Water Marks (61) ❑ Aquatic Invertebrates (1313) ❑ Dry -Season Water Table (C2) ❑ Sediment Deposits (62) ❑ Hydrogen Sulfide Odor (C1) ❑ Saturation Visible on Aerial Imagery (C9) ❑ Drift Deposits (63) ❑ Oxidized Rhizospheres along Living Roots (C3) ❑ Geomorphic Position (D2) ❑ Algal Mat or Crust (134) ❑ Presence of Reduced Iron (C4) ❑ Shallow Aquitard (D3) ❑ Iron Deposits (135) ❑ Recent Iron Reduction in Tilled Soils (C6) ❑ FAC-Neutral Test (D5) ❑ Surface Soil Cracks (66) ❑ Stunted or Stressed Plants (D1) (LRR A) ❑ Raised Ant Mounds (D6) (LRR A) ❑ Inundation Visible on Aerial Imagery (67) ❑ Other (explain in remarks) ❑ Frost -Heave Hummocks ❑ Sparsely Vegetated Concave Surface (138) Field Observations: Surface Water Present? Yes ❑ No 0 Depth (in): Water Table Present? Yes ® No El Depth Depth (in): 10 in. Hydrology Present? Yes ® No El Saturation Present? Yes ® No ❑ Depth (in): 0 in.* includes capillary fringe) Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available: Remarks: *Rainfall during investigations make saturation depth difficult to determine. US Army Corps of Engineers Western Mountains, Valleys, and Coast - Version 2.0 2 WATERSHED WETLAND DETERMINATION DATA FORM — Western Mountains, Valleys, and Coast Region DP - 3 Project/Site: 1XX S 293rd Street, Federal Way; parcel no. 7202500080 City/County: Federal Way Sampling date: 12/11/19 Applicant/Owner: S. Afichuk State: WA Sampling Point: DP-3 Investigator(s): L. Dougherty, G. Brennan Section, Township, Range: 05, 21N, 04E Landform (hillslope, terrace, etc): Hillslope Local relief (concave, convex, none): None Slope (%): 15 Subregion (LRR): A Lat: - Long: - Datum: - Soil Map Unit Name: Alderwood and Kitsap soils, very steep NWI classification: None Are climatic / hydrologic conditions on the site typical for this time of year? ❑X Yes ❑ No (If no, explain in remarks.) Are Vegetation ❑, Soil ❑, or Hydrology ❑ significantly disturbed? Are "Normal Circumstances" present on the site? © Yes ❑ No Are Vegetation ❑, Soil ❑, or Hydrology ❑ naturally problematic? (If needed, explain any answers in Remarks.) SUMMARY OF FINDINGS - Attach site map showing sampling point locations, transects, important features, etc. Hydrophytic Vegetation Present? Yes ® No ❑ Hydric Soils Present? Yes ❑ No ❑x Is the Sampled Area Yes ❑ No within a Wetland? Wetland Hydrology Present? Yes ❑ No ❑x Remarks: Wetland A out -pit. Climatic conditions considered "normal' per WETS table methodology. VEGETATION - Use scientific names of plants. Tree Stratum (Plot size: 5-m diameter) 1. Alnus rubra rooted across stream Absolute % Cover 80 Dominant Indicator Species? Status FAC Dominance Test worksheet: Number of Dominant Species 2 that are OBL, FACW, or FAC: (A) Total Number of Dominant 3 Species Across all Strata: (B) Percent of Dominant Species 67 that are OBL, FACW, or FAC: A/B 2• 3. 4. Sapling/Shrub Stratum (Plot size: 3-m diameter) 1. Rubus s ectabilis 80 60 = Total Cover Y FAC Prevalence Index worksheet: Total % Cover of: Multiply by: OBL species x 1 = FACW species x 2 = FAC species x 3 = FACU species x 4 = UPL species x 5 = Column Totals: (A) (B) Prevalence Index = B/A = 2. 3. 4. 5. 60 = Total Cover Herb Stratum (Plot size: 1-m diameter) 1. Pol stichum munitum 30 Y FACU 2. Tolmiea menziesii 20 Y FAC 3. Ranunculus re ens 2 N FAC Hydrophytic Vegetation Indicators: ❑ 1 - Rapid Test for Hydrophytic Vegetation ❑X 2 - Dominance Test is > 50% ❑ 3 - Prevalence Index is !- 3.0' ❑ 4 - Morphological Adaptations' (Provide supporting data in Remarks or on a separate sheet) ❑ 5 - Wetland Non -Vascular Plants' ❑ Problematic Hydrophytic Vegetation' (Explain) 'Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic. 4. Rubus ursinus 2 N FACU 5. 6. 7. 8. 9. 10. 11. Woody Vine Stratum (Plot size: 3-m diameter) 1. 54 = Total Cover Hydrophytic Vegetation Yes ® No ❑ Present? 2. 0 = Total Cover % Bare Ground in Herb Stratum: 46 Remarks: US Army Corps of Engineers Western Mountains, Valleys, and Coast - Version 2.0 SOIL Sampling Point: DP-3 Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.) Depth Matrix Redox Features inches Color moist % Color moist % Type' Loc' Texture Remarks 0-9 10YR 4/2 100 Clay loam 9-16 10YR 4/3 98 7.5YR 4/4 2 C M Clay loam 'Type: C=Concentration, D=De letion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. 2Loc: PL=Pore Lining, M=Matrix. Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) ❑ Histosol (Al) ❑ Sandy Redox (S5) ❑ Histic Epipedon (A2) ❑ Stripped Matrix (S6) ❑ Black Histic (A3) ❑ Loamy Mucky Mineral (F1) (except MLRA 1) ❑ Hydrogen Sulfide (A4) ❑ Loamy Gleyed Matrix (F2) ❑ Depleted Below Dark Surface (Al 1) ❑ Depleted Matrix (F3) ❑ Thick Dark Surface (Al2) ❑ Redox Dark Surface (F6) ❑ Sandy Mucky Mineral (S1) ❑ Depleted Dark Surface (F7) ❑ Sandy Gleyed Matrix (S4) ❑ Redox Depressions (F8) Indicators for Problematic Hydric Soils': ❑ 2cm Muck (A10) ❑ Red Parent Material (TF2) ❑ Very Shallow Dark Surface (TF12) ❑ Other (Explain in Remarks) ' Indicators of hydrophytic vegetation and wetland hydrology must be present, unless disturbed or problematic. Restrictive Layer (if present): Type: Hydric soil present? Yes El No Depth (inches): Remarks: HYDROLOGY Wetland Hydrology Indicators: Primary Indicators (minimum of one required: check all that apply) Secondary Indicators (2 or more required) ❑ Surface water (Al) El�nWpr Rtamne -eaves (except MLRA , 2, nn ❑ Water -Stained Leaves (139) (MLRA 1, ❑ High Water Table (A2) & " 2, 4A & 413) ❑ Saturation (A3) ❑ Salt Crust (1311) ❑ Drainage Patterns (610) ❑ Water Marks (61) ❑ Aquatic Invertebrates (1313) ❑ Dry -Season Water Table (C2) ❑ Sediment Deposits (62) ❑ Hydrogen Sulfide Odor (C1) ❑ Saturation Visible on Aerial Imagery (C9) ❑ Drift Deposits (63) ❑ Oxidized Rhizospheres along Living Roots (C3) ❑ Geomorphic Position (D2) ❑ Algal Mat or Crust (134) ❑ Presence of Reduced Iron (C4) ❑ Shallow Aquitard (D3) ❑ Iron Deposits (135) ❑ Recent Iron Reduction in Tilled Soils (C6) ❑ FAC-Neutral Test (D5) ❑ Surface Soil Cracks (66) ❑ Stunted or Stressed Plants (D1) (LRR A) ❑ Raised Ant Mounds (D6) (LRR A) ❑ Inundation Visible on Aerial Imagery (67) ❑ Other (explain in remarks) ❑ Frost -Heave Hummocks ❑ Sparsely Vegetated Concave Surface (138) Field Observations: Surface Water Present? Yes ❑ No 0 Depth (in): Water Table Present? Yes ElNo 0 Depth (in): Wetland Hydrology Present? Yes El No Saturation Present? Yes ❑ No 0 Depth (in): includes capillary fringe) Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available: Remarks: US Army Corps of Engineers Western Mountains, Valleys, and Coast - Version 2.0 2 WATERSHED WETLAND DETERMINATION DATA FORM — Western Mountains, Valleys, and Coast Region DP - 4 Project/Site: 1XX S 293rd Street, Federal Way; parcel no. 7202500080 City/County: Federal Way Sampling date: 12/11/19 Applicant/Owner: S. Afichuk State: WA Sampling Point: DP-4 Investigator(s): L. Dougherty, G. Brennan Section, Township, Range: 05, 21N, 04E Landform (hillslope, terrace, etc): Terrace Local relief (concave, convex, none): None Slope (%): 5 Subregion (LRR): A Lat: - Long: - Datum: - Soil Map Unit Name: Alderwood and Kitsap soils, very steep NWI classification: None Are climatic / hydrologic conditions on the site typical for this time of year? ❑x Yes ❑ No (If no, explain in remarks.) Are Vegetation ❑, Soil ❑, or Hydrology ❑ significantly disturbed? Are "Normal Circumstances" present on the site? © Yes ❑ No Are Vegetation ❑, Soil ❑, or Hydrology ❑ naturally problematic? (If needed, explain any answers in Remarks.) SUMMARY OF FINDINGS - Attach site map showing sampling point locations, transects, important features, etc. Hydrophytic Vegetation Present? Yes ® No ❑ Hydric Soils Present? Yes ❑x No ❑ Is the Sampled Area Yes ❑ No within a Wetland? Wetland Hydrology Present? Yes ❑ No ❑x Remarks: Terrace in hillslope. Climatic conditions considered "normal' per WETS table methodology. VEGETATION - Use scientific names of plants. Tree Stratum (Plot size: 5-m diameter) 1. Absolute % Cover Dominant Indicator Species? Status Dominance Test worksheet: Number of Dominant Species 1 that are OBL, FACW, or FAC: (A) Total Number of Dominant 1 Species Across all Strata: (B) Percent of Dominant Species 100 that are OBL, FACW, or FAC: A/B 2• 3. 4. Sapling/Shrub Stratum (Plot size: 3-m diameter) 1. 0 = Total Cover Prevalence Index worksheet: Total % Cover of: Multiply by: OBL species x 1 = FACW species x 2 = FAC species x 3 = FACU species x 4 = UPL species x 5 = Column Totals: (A) (B) Prevalence Index = B/A = 2. 3. 4. 5. 0 = Total Cover Herb Stratum (Plot size: 1-m diameter) 1. Phalaris arundinacea 100 Y FACW 2. Urtica dioica 3 N FAC 3. Hydrophytic Vegetation Indicators: ❑ 1 - Rapid Test for Hydrophytic Vegetation ❑x 2 - Dominance Test is > 50% ❑ 3 - Prevalence Index is !- 3.0' ❑ 4 - Morphological Adaptations' (Provide supporting data in Remarks or on a separate sheet) ❑ 5 - Wetland Non -Vascular Plants' ❑ Problematic Hydrophytic Vegetation' (Explain) 'Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic. Rubus armeniacus (too little to keep in shrub 4. stratum) 2 N FAC 5. 6. 7. 8. 9. 10. 11. Woody Vine Stratum (Plot size: 3-m diameter) 1. 105 = Total Cover Hydrophytic Vegetation Yes ® No ❑ Present? 2. 0 = Total Cover % Bare Ground in Herb Stratum: 0 Remarks: US Army Corps of Engineers Western Mountains, Valleys, and Coast - Version 2.0 SOIL Sampling Point: DP-4 Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.) Depth Matrix Redox Features inches Color moist % Color moist % Type' Loc' Texture Remarks 0-8 10YR 4/2 100 Loamy clay 8-16 5Y 4/2 98 7.5YR 4/6 2 C M Loamy clay 'Type: C=Concentration, D=De letion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. 2Loc: PL=Pore Lining, M=Matrix. Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) ❑ Histosol (Al) ❑ Sandy Redox (S5) ❑ Histic Epipedon (A2) ❑ Stripped Matrix (S6) ❑ Black Histic (A3) ❑ Loamy Mucky Mineral (F1) (except MLRA 1) ❑ Hydrogen Sulfide (A4) ❑ Loamy Gleyed Matrix (F2) ❑ Depleted Below Dark Surface (A11) ❑x Depleted Matrix (F3) ❑ Thick Dark Surface (Al2) ❑ Redox Dark Surface (F6) ❑ Sandy Mucky Mineral (S1) ❑ Depleted Dark Surface (F7) ❑ Sandy Gleyed Matrix (S4) ❑ Redox Depressions (F8) Indicators for Problematic Hydric Soils': ❑ 2cm Muck (A10) ❑ Red Parent Material (TF2) ❑ Very Shallow Dark Surface (TF12) ❑ Other (Explain in Remarks) ' Indicators of hydrophytic vegetation and wetland hydrology must be present, unless disturbed or problematic. Restrictive Layer (if present): Type: Hydric soil present? Yes ® No El Depth (inches): Remarks: HYDROLOGY Wetland Hydrology Indicators: Primary Indicators (minimum of one required: check all that apply) Secondary Indicators (2 or more required) ❑ Surface water (Al) El�AlRtpr Rtamne -eaves (except MLRA , 2, nn ❑ Water -Stained Leaves (139) (MLRA 1, ❑ High Water Table (A2) & " 2, 4A & 413) ❑ Saturation (A3) ❑ Salt Crust (B11) ❑ Drainage Patterns (610) ❑ Water Marks (61) ❑ Aquatic Invertebrates (1313) ❑ Dry -Season Water Table (C2) ❑ Sediment Deposits (62) ❑ Hydrogen Sulfide Odor (Cl) ❑ Saturation Visible on Aerial Imagery (C9) ❑ Drift Deposits (63) ❑ Oxidized Rhizospheres along Living Roots (C3) ❑ Geomorphic Position (D2) ❑ Algal Mat or Crust (134) ❑ Presence of Reduced Iron (C4) ❑ Shallow Aquitard (D3) ❑ Iron Deposits (135) ❑ Recent Iron Reduction in Tilled Soils (C6) ❑ FAC-Neutral Test (D5) ❑ Surface Soil Cracks (66) ❑ Stunted or Stressed Plants (D1) (LRR A) ❑ Raised Ant Mounds (D6) (LRR A) ❑ Inundation Visible on Aerial Imagery (67) ❑ Other (explain in remarks) ❑ Frost -Heave Hummocks ❑ Sparsely Vegetated Concave Surface (138) Field Observations: Surface Water Present? Yes ❑ No 0 Depth (in): Water Table Present? Yes ElNo 0 Depth (in): Wetland Hydrology Present? Yes El No Saturation Present? Yes ❑ No 0 Depth (in): includes capillary fringe) Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available: Remarks: Moist but not saturated. US Army Corps of Engineers Western Mountains, Valleys, and Coast - Version 2.0 Wetland name or number: Wetland A RATING SUMMARY - Western Washington Name of wetland (or ID #): Wetland A Date of site visit: 2 24 2020 Rated by: G. Brennan Trained by Ecology? MY ❑N Date of training: 10/2019 HGM Class used for rating: Slope Wetland has multiple HGM classes? NY ❑ N NOTE: Form is not complete without the figures requested (figures can be combined). Source of base aerial photo/map: Google Earth OVERALL WETLAND CATEGORY: III (based on functions 0 or special characteristics ❑) 1. Category of wetland based on FUNCTIONS ❑ Category I — Total score = 23 - 27 ❑ Category II —Total score = 20 - 22 ® Category III —Total score = 16 - 19 ❑ Category IV — Total score = 9 - 15 FUNCTION Improving Water Quality Hydrologic Habitat Circle the appropriate ratings Site Potential H M L H M L H M L Landscape Potential H M L H M L H M L Value H M L H M L H M L TOTAL Score Based on Ratings 5 6 6 17 2. Category based on SPECIAL CHARACTERISTICS of wetland CHARACTERISTIC CATEGORY Estuarine I II Wetland of High Conservation Value I Bog I Mature Forest I Old Growth Forest I Coastal Lagoon I II Interdunal I II III IV None of the above ❑x Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 Score for each function based on three ratings (order of ratings is not important) 9 = H,H,H 8 = H, H, M 7 = H,H,L 7 = H, M, M 6 = H,M,L 6 = M,M,M 5 = H,L,L 5 = M,M,L 4 = M,L,L 3 = L, L, L 1 Wetland name or number: Wetland A Maps and figures required to answer questions correctly for Western Washington Slope Wetlands Map of: To answer questions: Figure # Cowardin plant classes H 1.1, H 1.4 1 Hydroperiods H 1.2 2 Plant cover of dense trees, shrubs, and herbaceous plants S 1.3 3 Plant cover of dense, rigid trees, shrubs, and herbaceous plants (can be added to figure above) S 4.1 3 Boundary of 150 ft buffer (can be added to another figure) S 2.1, S 5.1 2 1 km Polygon: Area that extends 1 km from entire wetland edge - including polygons for accessible habitat and undisturbed habitat H 2.1, H 2.2, H 2.3 4 Screen capture of map of 303(d) listed waters in basin (from Ecology website) S 3.1, S 3.2 5 Screen capture of list of TMDLs for WRIA in which unit is found (from web) S 3.3 6 Wetland Rating System for Western WA: 2014 Update Rating Form — Effective January 1, 2015 Wetland name or number: Wetland A HGM Classification of Wetlands in Western Washington For questions 1-7, the criteria described must apply to the entire unit being rated. If the hydrologic criteria listed in each question do not apply to the entire unit being rated, you probably have a unit with multiple HGM classes. In this case, identify which hydrologic criteria in questions 1-7 apply, and go to Question 8. 1. Are the water levels in the entire unit usually controlled by tides except during floods? ONO - go to 2 El YES - the wetland class is Tidal Fringe - go to 1.1 1.1 Is the salinity of the water during periods of annual low flow below 0.5 ppt (parts per thousand)? NO - Saltwater Tidal Fringe (Estuarine) YES - Freshwater Tidal Fringe Ifyour wetland can be classified as a Freshwater Tidal Fringe use the forms for Riverine wetlands. If it is Saltwater Tidal Fringe it is an Estuarine wetland and is not scored. This method cannot be used to score functions for estuarine wetlands. 2. The entire wetland unit is flat and precipitation is the only source (>90%) of water to it. Groundwater and surface water runoff are NOT sources of water to the unit. ONO -goto3 ❑YES - The wetland class is Flats Ifyour wetland can be classified as a Flats wetland, use the form for Depressional wetlands. 3. Does the entire wetland unit meet all of the following criteria? El The vegetated part of the wetland is on the shores of a body of permanent open water (without any plants on the surface at anytime of the year) at least 20 ac (8 ha) in size; ❑At least 30% of the open water area is deeper than 6.6 ft (2 m). ONO - go to 4 El YES - The wetland class is Lake Fringe (Lacustrine Fringe) 4. Does the entire wetland unit meet all of the following criteria? ❑X The wetland is on a slope (slope can be very gradual), ❑x The water flows through the wetland in one direction (unidirectional) and usually comes from seeps. It may flow subsurface, as sheetflow, or in a swale without distinct banks, ❑X The water leaves the wetland without being impounded. ❑NO-goto5 DYES - The wetland class is Slope NOTE: Surface water does not pond in these type of wetlands except occasionally in very small and shallow depressions or behind hummocks (depressions are usually <3 ft diameter and less than 1 ft deep). 5. Does the entire wetland unit meet all of the following criteria? El The unit is in a valley, or stream channel, where it gets inundated by overbank flooding from that stream or river, El The overbank flooding occurs at least once every 2 years. Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 Wetland name or number: Wetland A LINO - go to 6 ❑YES - The wetland class is Riverine NOTE: The Riverine unit can contain depressions that are filled with water when the river is not flooding 6. Is the entire wetland unit in a topographic depression in which water ponds, or is saturated to the surface, at sometime during the year? This means that any outlet, if present, is higher than the interior of the wetland. ❑ NO - go to 7 ❑YES - The wetland class is Depressional 7. Is the entire wetland unit located in a very flat area with no obvious depression and no overbank flooding? The unit does not pond surface water more than a few inches. The unit seems to be maintained by high groundwater in the area. The wetland may be ditched, but has no obvious natural outlet. ❑ NO - go to 8 ❑YES - The wetland class is Depressional 8. Your wetland unit seems to be difficult to classify and probably contains several different HGM classes. For example, seeps at the base of a slope may grade into a riverine floodplain, or a small stream within a Depressional wetland has a zone of flooding along its sides. GO BACK AND IDENTIFY WHICH OF THE HYDROLOGIC REGIMES DESCRIBED IN QUESTIONS 1-7 APPLY TO DIFFERENT AREAS IN THE UNIT (make a rough sketch to help you decide). Use the following table to identify the appropriate class to use for the rating system if you have several HGM classes present within the wetland unit being scored. NOTE: Use this table only if the class that is recommended in the second column represents 10% or more of the total area of the wetland unit being rated. If the area of the HGM class listed in column 2 is less than 10% of the unit; classify the wetland using the class that represents more than 90% of the total area. SLOPE RATING USED. HGM classes within the wetland unit being rated HGM class to use in rating Slo e + Riverine Riverine Slope + Depressional Depressional Slope + Lake Fringe Lake Fringe Depressional + Riverine along stream within boundary of depression Depressional Depressional + Lake Fringe Depressional Riverine + Lake Fringe Riverine Salt Water Tidal Fringe and any other class of freshwater wetland Treat as ESTUARINE Ifyou are still unable to determine which of the above criteria apply to your wetland, or ifyou have more than 2 HGM classes within a wetland boundary, classify the wetland as Depressional for the rating. Wetland Rating System for Western WA: 2014 Update 4 Rating Form - Effective January 1, 2015 Wetland name or number: Wetland A SLOPE WETLANDS Water Quality Functions - Indicators that the site functions to improve water quality S 1.0. Does the site have the potential to improve water quality? S 1.1. Characteristics of the average slope of the wetland: (a 1%slope has a 1 ft vertical drop in elevation for every 100 ft of horizontal distance) ❑ Slope is 1% or less points = 3 ❑ Slope is > 1%-2% points = 2 ❑ Slope is > 2%-5% points = 1 ❑X Slope is greater than 5% points = 0 S 1.2. The soil 2 in below the surface (or duff layer) is true clay or true organic (use NRCS definitions): Yes = 3 No = 0 0 S 1.3. Characteristics of the plants in the wetland that trap sediments and pollutants: Choose the points appropriate for the description that best fits the plants in the wetland. Dense means you have trouble seeing the soil surface (>75% cover), and uncut means not grazed or mowed and plants are higher than 6 in. ❑ Dense, uncut, herbaceous plants > 90% of the wetland area points = 6 2 ❑ Dense, uncut, herbaceous plants > % of area points = 3 ❑X Dense, woody, plants > % of area points = 2 ❑ Dense, uncut, herbaceous plants > % of area points =1 ❑ Does not meet any of the criteria above for plants points = 0 Total for S 1 Add the points in the boxes above 2 Rating of Site Potential If score is: ❑ 12 = H ❑ 6-11 = M ❑X 0-5 = L Record the rating on the first page S 2.0. Does the landscape have the potential to support the water quality function of the site? S 2.1. Is > 10% of the area within 150 ft on the uphill side of the wetland in land uses that generate pollutants? 1 ❑XYes=1 ❑ No= 0 S 2.2. Are there other sources of pollutants coming into the wetland that are not listed in question S 2.1? 0 Other sources ❑Yes = 1 ❑X No = 0 Total for S 2 Add the points in the boxes above 1 Rating of Landscape Potential If score is: ❑X 1-2 = M ❑0 = L Record the rating on the first page S 3.0. Is the water quality improvement provided by the site valuable to society? S 3.1. Does the wetland discharge directly (i.e., within 1 mi) to a stream, river, lake, or marine water that is on the 1 303(d) list? ❑X Yes = 1 ❑ No = 0 S 3.2. Is the wetland in a basin or sub -basin where water quality is an issue? At least one aquatic resource in the basin is 0 on the 303(d) list. ❑Yes = 1 ❑X No = 0 S 3.3. Has the site been identified in a watershed or local plan as important for maintaining water quality? Answer YES 0 if there is a TMDL for the basin in which unit is found. ❑Yes = 2 ❑X No = 0 Total for S 3 Add the points in the boxes above 1 Rating of Value If score is: ❑2-4 = H ❑X 1= M ❑0 = L Record the rating on the first page 11 Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 Wetland name or number: Wetland A SLOPE WETLANDS Hydrologic Functions - Indicators that the site functions to reduce flooding and stream erosion S 4.0. Does the site have the potential to reduce flooding and stream erosion? S 4.1. Characteristics of plants that reduce the velocity of surface flows during storms: Choose the points appropriate for the description that best fits conditions in the wetland. Stems of plants should be thick enough (usually>1/8$ in), or dense enough, to remain erect during surface flows. 0 ❑ Dense, uncut, rigid plants cover > 90% of the area of the wetland points = 1 ❑x All other conditions points = 0 Rating of Site Potential If score is: ❑ 1 = M ❑X 0 = L Record the rating on the first page S 5.0. Does the landscape have the potential to support the hydrologic functions of the site? S 5.1. Is more than 25% of the area within 150 ft upslope of wetland in land uses or cover that generate excess surface 1 runoff? ❑X Yes = 1 ElNo = 0 Rating of Landscape Potential If score is: ❑X 1 = M ❑0 = L Record the rating on the first page S 6.0. Are the hydrologic functions provided by the site valuable to society? S 6.1. Distance to the nearest areas downstream that have flooding problems: ❑X The sub -basin immediately down -gradient of site has flooding problems that result in damage to human or natural resources (e.g., houses or salmon redds) points = 2 2 ❑ Surface flooding problems are in a sub -basin farther down -gradient points = 1 ❑ No flooding problems anywhere downstream points = 0 S 6.2. Has the site been identified as important for flood storage or flood conveyance in a regional flood control plan? 0 ❑Yes=2 ❑X No=0 Total for S 6 Add the points in the boxes above 2 Rating of Value If score is: ❑X 2-4 = H ❑ 1= M ❑0 = L Record the rating on the first page NOTES and FIELD OBSERVATIONS: Wetland Rating System for Western WA: 2014 Update 12 Rating Form - Effective January 1, 2015 Wetland name or number: Wetland A These questions apply to wetlands of all HGM classes. HABITAT FUNCTIONS - Indicators that site functions to provide important habitat H 1.0. Does the site have the potential to provide habitat? H 1.1. Structure of plant community: Indicators are Cowardin classes and strata within the Forested class. Check the Cowardin plant classes in the wetland. Up to 10 patches maybe combined foreach class to meet the threshold of Mac or more than 10% of the unit if it is smaller than 2.5 ac. Add the number of structures checked. ❑ Aquatic bed 4 structures or more: points = 4 ❑X Emergent 3 structures: points = 2 ❑x Scrub -shrub (areas where shrubs have > 30% cover) 2 structures: points = 1 1 ❑ Forested (areas where trees have > 30% cover) 1 structure: points = 0 If the unit has a Forested class, check if. ❑ The Forested class has 3 out of 5 strata (canopy, sub -canopy, shrubs, herbaceous, moss/ground-cover) that each cover 20% within the Forested polygon H 1.2. Hydroperiods Check the types of water regimes (hydroperiods) present within the wetland. The water regime has to cover more than 10% of the wetland or % ac to count (see text for descriptions of hydroperiods). ❑ Permanently flooded or inundated 4 or more types present: points = 3 ❑ Seasonally flooded or inundated 3 types present: points = 2 ❑ Occasionally flooded or inundated 2 types present: points =1 1 ❑X Saturated only 1 type present: points = 0 ❑ Permanently flowing stream or river in, or adjacent to, the wetland ❑x Seasonally flowing stream in, or adjacent to, the wetland ❑ Lake Fringe wetland 2 points ❑ Freshwater tidal wetland 2 points H 1.3. Richness of plant species Count the number of plant species in the wetland that cover at least 10 ft2. Different patches of the same species can be combined to meet the size threshold and you do not have to name the species. Do not include Eurasian milfoil, reed canarygrass, purple loosestrife, Canadian thistle 1 If you counted: ❑ > 19 species points = 2 ❑X 5 -19 species points =1 ❑ < 5 species points = 0 H 1.4. Interspersion of habitats Decide from the diagrams below whether interspersion among Cowardin plants classes (described in H 1.1), or the classes and unvegetated areas (can include open water or mudflats) is high, moderate, low, or none. If you have four or more plant classes or three classes and open water, the rating is always high. O #r 2 ❑ None = 0 points ❑ Low = 1 point ❑X Moder it = is All three diagrams in this row are ❑ HIGH = 3points Wetland Rating System for Western WA: 2014 Update 13 Rating Form - Effective January 1, 2015 Wetland name or number: Wetland A H 1.5. Special habitat features: Check the habitat features that are present in the wetland. The number of checks is the number of points. ❑X Large, downed, woody debris within the wetland (> 4 in diameter and 6 ft long). ❑ Standing snags (dbh > 4 in) within the wetland. ❑ Undercut banks are present for at least 6.6 ft (2 m) AND/OR overhanging plants extends at least 3.3 ft (1 m) over a stream (or ditch) in, or contiguous with the wetland, for at least 33 ft (10 m). 2 ❑ Stable steep banks of fine material that might be used by beaver or muskrat for denning (> 30 degree slope) OR signs of recent beaver activity are present (cut shrubs or trees that have not yet weathered where wood is exposed). ❑ At least % ac of thin -stemmed persistent plants or woody branches are present in areas that are permanently or seasonally inundated (structures foregg-laying by amphibians). ❑X Invasive plants cover less than 25% of the wetland area in every stratum of plants (see H 1.1 for list of strata). Total for H 1 Add the points in the boxes above 7 Rating of Site Potential If score is: ❑ 15-18 = H ❑X 7-14 = M ❑ 0-6 = L Record the rating on the first page H 2.0. Does the landscape have the potential to support the habitat functions of the site? H 2.1. Accessible habitat (include only habitat that directly abuts wetland unit). Calculate: % undisturbed habitat + [(%moderate and low intensity land uses)/2] = 7.5% + (0%/2) = 7.5% If total accessible habitat is: ❑ > 1/3 (33.3%) of 1 km Polygon points = 3 0 ❑ 20-33% of 1 km Polygon points = 2 ❑ 10-19% of 1 km Polygon points = 1 ❑X < 10% of 1 km Polygon points = 0 H 2.2. Undisturbed habitat in 1 km Polygon around the wetland. Calculate: % undisturbed habitat + [(%moderate and low intensity land uses)/2 = 9.9% + (25.9%/2) = 22.8% ❑ Undisturbed habitat > 50% of Polygon points = 3 1 ❑ Undisturbed habitat 10-50% and in 1-3 patches points = 2 ❑X Undisturbed habitat 10-50% and > 3 patches points =1 ❑ Undisturbed habitat < 10% of 1 km Polygon points = 0 H 2.3. Land use intensity in 1 km Polygon: If ❑X > 50% of 1 km Polygon is high intensity land use points = (- 2) -2 ❑ < 50% of 1 km Polygon is high intensity points = 0 Total for H 2 Add the points in the boxes above -1 Rating of Landscape Potential If score is: ❑4-6 = H ❑ 1-3 = M ❑X < 1 = L Record the rating on the first page H 3.0. Is the habitat provided by the site valuable to society? H 3.1. Does the site provide habitat for species valued in laws, regulations, or policies? Choose only the highest score that applies to the wetland being rated. Site meets ANY of the following criteria: points = 2 ® It has 3 or more priority habitats within 100 m (see next page) ❑ It provides habitat for Threatened or Endangered species (any plant or animal on the state or federal lists) ❑ It is mapped as a location for an individual WDFW priority species 2 ❑ It is a Wetland of High Conservation Value as determined by the Department of Natural Resources ❑ It has been categorized as an important habitat site in a local or regional comprehensive plan, in a Shoreline Master Plan, or in a watershed plan ❑ Site has 1 or 2 priority habitats (listed on next page) within 100 m points = 1 ❑ Site does not meet any of the criteria above points = 0 Rating of Value If score is: ®2 = H ❑ 1= M 70 = L Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 Record the rating on the first page 14 Wetland name or number: Wetland A WDFW Priority Habitats Priority habitats listed by WDFW (see complete descriptions of WDFW priority habitats, and the counties in which they can be found, in: Washington Department of Fish and Wildlife. 2008. Priority Habitat and Species List. Olympia, Washington. 177 pp. httl2://wdfw.wa.gov/publications/00165/wdfw00165.pdf or access the list from here: httl2:/ /wdfw.wa.gov/conservation/phs/list/) Count how many of the following priority habitats are within 330 ft (100 m) of the wetland unit: NOTE: This question is independent of the land use between the wetland unit and the priority habitat. ❑ Aspen Stands: Pure or mixed stands of aspen greater than 1 ac (0.4 ha). ❑X Biodiversity Areas and Corridors: Areas of habitat that are relatively important to various species of native fish and wildlife (full descriptions in WDFW PHS report). ❑ Herbaceous Balds: Variable size patches of grass and forbs on shallow soils over bedrock. ❑ Old-growth/Mature forests: Old -growth west of Cascade crest - Stands of at least 2 tree species, forming a multi- layered canopy with occasional small openings; with at least 8 trees/ac (20 trees/ha) > 32 in (81 cm) dbh or > 200 years of age. Mature forests - Stands with average diameters exceeding 21 in (53 cm) dbh; crown cover may be less than 100%; decay, decadence, numbers of snags, and quantity of large downed material is generally less than that found in old -growth; 80-200 years old west of the Cascade crest. ❑ Oregon White Oak: Woodland stands of pure oak or oak/conifer associations where canopy coverage of the oak component is important (full descriptions in WDFW PHS report p.158 -see web link above). ® Riparian: The area adjacent to aquatic systems with flowing water that contains elements of both aquatic and terrestrial ecosystems which mutually influence each other. ❑ Westside Prairies: Herbaceous, non -forested plant communities that can either take the form of a dry prairie or a wet prairie (full descriptions in WDFW PHS report p. 161 -see web link above). ❑ Instream: The combination of physical, biological, and chemical processes and conditions that interact to provide functional life history requirements for instream fish and wildlife resources. ❑ Nearshore: Relatively undisturbed nearshore habitats. These include Coastal Nearshore, Open Coast Nearshore, and Puget Sound Nearshore. (full descriptions of habitats and the definition of relatively undisturbed are in WDFW report- see web link on previous page). ❑ Caves: A naturally occurring cavity, recess, void, or system of interconnected passages under the earth in soils, rock, ice, or other geological formations and is large enough to contain a human. ❑ Cliffs: Greater than 25 ft (7.6 m) high and occurring below 5000 ft elevation. ❑ Talus: Homogenous areas of rock rubble ranging in average size 0.5 - 6.5 ft (0.15 - 2.0 m), composed of basalt, andesite, and/or sedimentary rock, including riprap slides and mine tailings. May be associated with cliffs. M Snags and Logs: Trees are considered snags if they are dead or dying and exhibit sufficient decay characteristics to enable cavity excavation/use by wildlife. Priority snags have a diameter at breast height of > 20 in (51 cm) in western Washington and are > 6.5 ft (2 m) in height. Priority logs are > 12 in (30 cm) in diameter at the largest end, and > 20 ft (6 m) long. Note: All vegetated wetlands are by definition a priority habitat but are not included in this list because they are addressed elsewhere. Wetland Rating System for Western WA: 2014 Update 15 Rating Form - Effective January 1, 2015 Wetland name or number: Wetland A CATEGORIZATION BASED ON SPECIAL CHARACTERISTICS Wetland Type Category Check off any criteria that apply to the wetland. Circle the category when the appropriate criteria are met. SC 1.0. Estuarine wetlands Does the wetland meet the following criteria for Estuarine wetlands? ❑ The dominant water regime is tidal, ❑ Vegetated, and ❑ With a salinity greater than 0.5 ppt ❑Yes -Go to SC 1.1 ❑X No= Not an estuarine wetland SC 1.1. Is the wetland within a National Wildlife Refuge, National Park, National Estuary Reserve, Natural Area Preserve, State Park or Educational, Environmental, or Scientific Reserve designated under WAC 332-30-151? Cat. ❑Yes = Category I ❑No - Go to SC 1.2 SC 1.2. Is the wetland unit at least 1 ac in size and meets at least two of the following three conditions? ❑ The wetland is relatively undisturbed (has no diking, ditching, filling, cultivation, grazing, and has Cat. less than 10% cover of non-native plant species. (If non-native species are Spartina, see page 25) ❑ At least % of the landward edge of the wetland has a 100 ft buffer of shrub, forest, or un-grazed or un- mowed grassland. Cat. II ❑ The wetland has at least two of the following features: tidal channels, depressions with open water, or contiguous freshwater wetlands. El Yes = Category I ❑ No= Category II SC 2.0. Wetlands of High Conservation Value (WHCV) SC 2.1. Has the WA Department of Natural Resources updated their website to include the list of Wetlands of High Conservation Value? ❑X Yes - Go to SC 2.2 ❑ No - Go to SC 2.3 SC 2.2. Is the wetland listed on the WDNR database as a Wetland of High Conservation Value? http://www.dnr.wa.gov/NHPwetlandviewer ❑Yes = Category I ❑X No = Not a WHCV SC 2.3. Is the wetland in a Section/Township/Range that contains a Natural Heritage wetland? Cat. I http://file.dnr.wa.gov/publications/amp nh wetlands trs.pdf ❑Yes - Contact WNHP/WDNR and go to SC 2.4 ❑ No = Not a WHCV SC 2.4. Has WDNR identified the wetland within the S/T/R as a Wetland of High Conservation Value and listed it on their website? ❑Yes = Category I ❑ No = Not a WHCV SC 3.0. Bogs Does the wetland (or any part of the unit) meet both the criteria for soils and vegetation in bogs? Use the key below. If you answer YES you will still need to rate the wetland based on its functions. SC 3.1. Does an area within the wetland unit have organic soil horizons, either peats or mucks, that compose 16 in or more of the first 32 in of the soil profile? ❑Yes - Go to SC 3.3 ❑X No - Go to SC 3.2 SC 3.2. Does an area within the wetland unit have organic soils, either peats or mucks, that are less than 16 in deep over bedrock, or an impermeable hardpan such as clay or volcanic ash, or that are floating on top of a lake or pond? ❑Yes - Go to SC 3.3 0 No = Is not a bog SC 3.3. Does an area with peats or mucks have more than 70% cover of mosses at ground level, AND at least a 30% Cat. cover of plant species listed in Table 4? ❑Yes = Is a Category I bog ❑ No - Go to SC 3.4 NOTE: If you are uncertain about the extent of mosses in the understory, you may substitute that criterion by measuring the pH of the water that seeps into a hole dug at least 16 in deep. If the pH is less than 5.0 and the plant species in Table 4 are present, the wetland is a bog. SC 3.4. Is an area with peats or mucks forested (> 30% cover) with Sitka spruce, subalpine fir, western red cedar, western hemlock, lodgepole pine, quaking aspen, Engelmann spruce, or western white pine, AND any of the species (or combination of species) listed in Table 4 provide more than 30% of the cover under the canopy? ❑Yes = Is a Category I bog ❑ No = Is not a bog Wetland Rating System for Western WA: 2014 Update 16 Rating Form - Effective January 1, 2015 Wetland name or number: Wetland A SC 4.0. Forested Wetlands Does the wetland have at least 1 contiguous acre of forest that meets one of these criteria for the WA Department of Fish and Wildlife's forests as priority habitats? If you answer YES you will still need to rate the wetland based on its functions. ❑ Old -growth forests (west of Cascade crest): Stands of at least two tree species, forming a multi -layered canopy with occasional small openings; with at least 8 trees/ac (20 trees/ha) that are at least 200 years of Cat. age OR have a diameter at breast height (dbh) of 32 in (81 cm) or more. ❑ Mature forests (west of the Cascade Crest): Stands where the largest trees are 80- 200 years old OR the species that make up the canopy have an average diameter (dbh) exceeding 21 in (53 cm). ❑Yes = Category 1 ❑X No = Not a forested wetland for this section SC 5.0. Wetlands in Coastal Lagoons Does the wetland meet all of the following criteria of a wetland in a coastal lagoon? ❑ The wetland lies in a depression adjacent to marine waters that is wholly or partially separated from marine waters by sandbanks, gravel banks, shingle, or, less frequently, rocks ❑ The lagoon in which the wetland is located contains ponded water that is saline or brackish (> 0.5 ppt) during most of the year in at least a portion of the lagoon (needs to be measured near the Cat. bottom) ❑Yes - Go to SC 5.1 ❑X No = Not a wetland in a coastal lagoon SC 5.1. Does the wetland meet all of the following three conditions? ❑ The wetland is relatively undisturbed (has no diking, ditching, filling, cultivation, grazing), and has Cat. II less than 20% cover of aggressive, opportunistic plant species (see list of species on p. 100). ❑ At least % of the landward edge of the wetland has a 100 ft buffer of shrub, forest, or un-grazed or un- mowed grassland. ❑ The wetland is larger than 1/io ac (4350 ftz) ❑Yes = Category I ❑ No = Category II SC 6.0. Interdunal Wetlands Is the wetland west of the 1889 line (also called the Western Boundary of Upland Ownership or WBUO)? If you answer yes you will still need to rate the wetland based on its habitat functions. In practical terms that means the following geographic areas: Cat ❑ Long Beach Peninsula: Lands west of SR 103 ❑ Grayland-Westport: Lands west of SR 105 ❑ Ocean Shores-Copalis: Lands west of SR 115 and SR 109 Cat. II ❑Yes - Go to SC 6.1 ❑X No = not an interdunal wetland for rating SC 6.1. Is the wetland 1 ac or larger and scores an 8 or 9 for the habitat functions on the form (rates H,H,H or H,H,M Cat. III for the three aspects of function)? ❑Yes = Category I ❑ No - Go to SC 6.2 SC 6.2. Is the wetland 1 ac or larger, or is it in a mosaic of wetlands that is 1 ac or larger? ❑Yes = Category II ❑ No - Go to SC 6.3 Cat. IV SC 6.3. Is the unit between 0.1 and 1 ac, or is it in a mosaic of wetlands that is between 0.1 and 1 ac? ❑Yes = Category III ❑ No = Category IV Category of wetland based on Special Characteristics NA If you answered No for all types, enter "Not Applicable" on Summary Form Wetland Rating System for Western WA: 2014 Update 17 Rating Form - Effective January 1, 2015 A Wetland name or number: A This page left blank intentionally Wetland Rating System for Western WA: 2014 Update 18 Rating Form - Effective January 1, 2015 2014 Ecology Wetland Rating Form Figures AFICHUK PROPERTY WetlandA (Slope).........................................................................................................................................1 Figure 1. Cowardin plant classes — H1.1, H1.4..........................................................................................1 Figure 2. Hydroperiods and 150-foot area — H1.2, 52.1, 55.1.................................................................. 2 Figure 3. Plant cover of dense and rigid trees, shrubs, and herbaceous plants — 51.3, 54.1...................3 Figure 4. Undisturbed habitat and moderate -low intensity land uses within 1 km from wetland edge including polygon for accessible habitat — H2.1, H2.2, H2.3..................................................4 Figure 5. Screen -capture of 303(d) listed waters in basin — S3.11 53.2....................................................5 Figure 6. Screen -capture of TMDL map for sub -basin in which unit is found — S3.3 ............................... 6 Page left blank intentionally to allow for duplex printing. WETLAND A (SLOPE) Figure 1. Cowardin plant classes — H1.1, H1.4 Features depicted are not to scale. Sketches are based on available data and best professional judgment. Wetland Figures - 1 Figure 2. Hydroperiods and 150-foot area — H1.2, S2.1, S5.1 Features depicted are not to scale. Sketches are based on available data and best professional judgment. Wetland Figures - 2 Figure 3. Plant cover of dense and rigid trees, shrubs, and herbaceous plants — S1.3, S4.1 Features depicted are not to scale. Sketches are based on available data and best professional judgment. Wetland Figures - 3 Figure 4. Undisturbed habitat and moderate -low intensity land uses within 1 km from wetland edge including polygon for accessible habitat — H2.1, H2.2, H2.3 Features depicted are not to scale. Sketches are based on available data and best professional judgment. Wetland Figures - 4 303(d) 578rge, .. • s 2ez Delco and East s1 Passages Bacteria Listing _ N 5W i ....I [f3 99 .•;I299RlS, d Wetland Unit � n ahasatnst s s�,3ro a 5W 297th SE p� rS SZg Rd w SW 2%th PI P. .gac P. y Pan W 299th St 6 5 29B�c�v 4'Q m4 d Is P � 4 d1 s 83U,sf 51 ��.026npo�nvR ! S 7[11rid �t 9�urm: Efn, HERF rrnemeN P D ,, GE.OGOS, FAO, NPS, NRCMI, GN9e#, IGN, KatlBellr NI, OeeaW! 8uea9, EJfi leper, MER Efn CNna plorg I(nng1. I[> Op�S[eelMap unFGAata�d becember 12, 2019 Assessed WatorslSedlment Water y Category 5 - 303d V Category 4C Category 4B Category 4A Category 2 Category 1 Sediment ® Category 5 - 303d ® Category 4C ® Category 4B ® Category 4A air. Category 2 ® Category 1 Mies 0 0.925 0.25 ECOLOGY Figure 5. Screen -capture of 303(d) listed waters in basin — S3.1, S3.2 Features depicted are not to scale. Sketches are based on available data and best professional judgment. Wetland Figures - 5 December 12, 2C10 TMDL WQ Improvement Projects ... 4W Approved in Development Puget Sound Nutrient Source Reduction Project Wetland unit located in the Duwamish-Green 104 Poser a , Basin N Q` ro Miles ?aurcex Epi, IIEHE, C rrin, Meinep, Immxn P CUq. GEBoo, uses, 0 025 0.5 1 - - - F�, NP3, NRCJM, fafEa�e, IGN. I(eEffR� NL, Odd Sihey, Efn ftV�Ql.I4uoasv�..wm,Ma,v�,a,e mA ECOLOGY "%W� Figure 6. Screen -capture of TMDL map for sub -basin in which unit is found — S3.3 Features depicted are not to scale. Sketches are based on available data and best professional judgment. Wetland Figures - 6 Appendix C TREE INVENTORY REPORT 2 THE WATERSHED COMPANY October 29, 2020 Stan Afichuk 29328 1st Ave S Federal Way, WA 98003 206-708-0065 Via email: stan@greenbuilddev.com Re: Afichuk, Tree Inventory Report The Watershed Company Reference Number: 191123 Dear Stan: S C I E N C E & D E S I G N On July 1, 2020, ISA Certified Arborist® Roen Hohlfeld visited the undeveloped property (Parcel #7202500080) located at 1xx S 293rd Street in Federal Way, Washington 98001 to inventory existing trees on the property. This report summarizes the findings of the study and details applicable regulations. The following documents are enclosed: • Tree Inventory Table • Off -Parcel Tree Inventory Table • Tree Retention Plan Findings Summary A total of 37 significant trees were inventoried on the subject property, with an additional 23 non -significant trees tallied on -site, totaling 72.5 tree credits. Twenty-one off -parcel significant trees were included in the inventory. Federal Way Revised Code (FWRC) requires 11 tree units to meet density requirements on this 0.43-acre parcel. Study Area The subject property totals approximately 0.43 acres in size and is currently undeveloped. The site is slopes steeply down to the north, with a ravine and small stream extending north from the southeast area of the parcel. The site is generally forested with native deciduous trees; a disturbed area is located in the southwest portion of the property. 750 Sixth Street South I Kirkland, WA 98033 P 425.822.5242 f 425.827.8136 1 watershedco.com Tree Inventory Report Afichuk Project October 2020 Page 2 Proposed Project The subject property is proposed to be developed with a single-family residence, associated site access and landscape improvements. To achieve this, trees located in proximity to the proposed development may be impacted. Elements of proposed improvements that may impact trees include clearing, grading, trenching for utilities, and altered environmental factors on -site including wind direction, sun exposure, and decreased water infiltration from impervious surfaces. Methods The study area for the tree inventory includes parcel #7202500080 and significant trees rooted within approximately 50 feet of the parcel boundary. Per Federal Way Revised Code, a significant tree is 'any self-supporting perennial woody plant characterized by one main stem or trunk of at least six inches in diameter measured four and one-half feet above ground, or a multi -stemmed trunk system with a definite crown, maturing at a height of a least 20 feet above ground level' (FWRC 19.05.200). Inventory methods were developed to meet the City of Federal Way tree retention requirements. A round one -and -one -quarter inch -wide, numbered aluminum tag was affixed to the side of the trunk of significant trees presumed to be located on -site (tree tag #1301-1340). Off -site trees were not tagged nor measured; rather physical attributes were estimated from the subject property. The attributes collected during the field survey are described in Table 1, below. The database (Tree Inventory Table) contains the data collected for each tree inventoried. General attributes documented for all inventoried trees include the unique identification number and name of plant species. Physical attributes include number of stems, diameter at breast height (DBH), height, canopy radius, condition, and assessment notes. Non -significant trees (one- to six -inches DBH) located within the driplines of significant trees also were tallied during the assessment of significant trees. Tree Inventory Report Afichuk Project October 2020 Page 3 Table 1. Attributes recorded for all inventoried vegetation and that are presented in the spreadsheet database. Attribute Description of Attribute ID NUMBER Unique number assigned to an assessed tree. This number corresponds to the tag number in the field. SCIENTIFIC NAME I Formal scientific name conforming to the International Code of Nomenclature. COMMON NAME I Name that is based on normal or common language of the Pacific Northwest. STEMS Number of trunks or shoots that contribute significantly to the canopy. DBH Diameter at Breast Height; or 4.5 feet from the ground surface. HEIGHT Approximate distance from the ground surface at the trunk to the highest point of the subject tree as visually estimated. CANOPY RADIUS Measurement from the stem to the limits of the drip line, or end of branches. Critical root zone. Health rating of an assessed tree using a 5-tier system as follows: 1— Excellent: No apparent problems with the tree. Form is exemplary for the species. 2 — Good: Few minor defects such as crossed branches, minor foliage die -back, minor trunk damage, or unbalance canopy. CONDITION 3 — Fair: Several minor problems exist. 4 — Poor: Major defects visible such as significant trunk decay, codominant leaders with included bark, significant canopy die -back, major cracks in a stem or major limbs, and/or other structural problems. Topped trees are generally considered poor. 5 — Dying: Tree is in a state of significant decline. 6 — Dead: Tree is dead. In general, tree diameter was measured at four feet above the ground surface (diameter at breast height, or "DBH") using a graduated metal logger's DBH tape. Trees with multiple trunks arising from the ground were measured using methodology from Guide for Plant Appraisal (Gooding, et al. 2000). The cross -sectional areas of stems contributing to the canopy were summed and used to generate a singular combined DBH for the tree. The singular DBH number allows for comparison to other single -stemmed trees and for more accurate permitting and tree retention calculations. Methods for measuring diameter of trees with major leans, on steep slopes, and with multiple trunks or stems generally followed those outlined in the Guide for Plant Appraisal (Gooding, et Tree Inventory Report Afichuk Project October 2020 Page 4 al. 2000). Visual estimates of trunk diameter were used where direct access to the tree was not allowed or not feasible. Tree data and geospatial locations were collected in the field using an iPad with ArcGIS Collector application. Data collected in the field are summarized in the Tree Inventory Sketch and Tree Inventory Table, attached. Findings Tree Inventory Results A total of 37 significant trees are located on the subject parcel. 23 non -significant trees (one to six inches in diameter) were tallied on -site. A total of 21 off -site trees were assessed from the parcel boundary. Significant tree species on the subject parcel were limited to Acer macrophyllum (bigleaf maple), Alnus rubra (red alder), and Tsuga heterophylla (western hemlock), all native to the Pacific northwest. The most common tree species on the subject parcel is red alder, followed by bigleaf maple with 23 and 11 individuals, respectively. Overall, the average DBH of significant trees located on the parcel is 16.7-inches, with 13 trees measuring greater than 18-inches DBH. The largest tree is a bigleaf maple (#1328) with a DBH of 55.1 inches. Fourteen trees, or 38-percent of the total, were given a health rating of 4 (poor) or worse; many of these trees have been previously topped. A summary of attributes for significant tree species identified on -site is provided in Table 2 below. Table 2. Summary of tree species and DBH size. Tree Name Acer macrophyllum (Bigleaf maple) Alnus rubra (red alder) Tsuga heterophylla (Western hemlock) TOTAL Total Average DBH Largest DBH Inventoried (In.) (In.) 11 1 20.7 1 55.1 23 14.1 1 23.6 3 21.7 1 24.6 37 16.7 1 55.1 The twenty-one off -parcel significant trees included in the inventory consist of the same species as those rooted within the subject parcel. The average DBH of these trees is approximately 19- inches. 10 trees were estimated to have a DBH greater than 18-inches. The three largest trees, all Tree Inventory Report Afichuk Project October 2020 Page 5 bigleaf maples, were each estimated to have a DBH of 36 inches. Five trees were given a health rating of 4 (poor) or worse. Tree Retention and Removal With the proposed site plan (provided by Urban Design Group, May 22, 2020) trees located in proximity to the development area will be impacted to varying degrees. Table 3 summarizes trees that are anticipated to be impacted by the proposed development as a result of disturbance with the critical root zone (CRZ), defined as 12 inches radius for every one inch of tree diameter measured at four and one-half feet above ground. Table 3. Tree Impact and Removal Summary. Combined Height Radius Tree Proposed Tag # Tree Name Condition DBH (In) 11.5 (Ft) (Ft) Units for Removal 1301 Anus rubra (Red Alder) 10.8 60 15 2 1.5 NO NO 1302 Alnus rubra (Red Alder) 60 12 2 1.5 1303 Alnus rubra 13.6 NO (Red Alder) 60 15 2 2.0 1305 Alnus rubra 9.8 NO (Red Alder) 60 10 4 n/a 1306 Alnus rubra 11.6 NO (Red Alder) 60 15 3 1.5 1307 Alnus rubra 11.8 NO (Red Alder) 65 15 2 1.5 1308 Alnus rubra 10.7 (Red Alder) 25 5 4 n/a YES 1309 Alnus rubra 8.9 (Red Alder) 50 12 4 n/a YES The proposed development area has been cited in a previously disturbed area in order to minimize impacts to significant trees. However, implementation of the site plan will require the removal of two trees, #1308 and #1309. Tree #1308 and #1308 are both red alders in poor (4) condition with DBHs of 10.7-inches and 8.9-inches, respectively. These trees will be directly impacted by construction of the single-family residence and related grading. Tree Inventory Report Afichuk Project October 2020 Page 6 Additionally, six trees (#1301, 1302, 1303, 1305, 1306, and 1307) are expected to receive impacts to their critical root zones. These trees are all red alders with DBHs ranging from 9.8-inches to 13.6-inches. The trees are generally in fair to good condition, with the exception of #1305 which has a poor (4) condition rating. It is not expected that the extent of impacts proposed within the critical root zones of these six trees will cause their conditions to decline to a point that would require their removal when tree protection measures are followed. No off -parcel tree impacts or removals are anticipated. Local Regulations The City of Federal Way's tree and vegetation retention standards are outlined in the Federal Way Revised Code (FWRC), Chapter 19.120 - Clearing, Grading, and Tree and Vegetation Retention. The subject parcel is zoned RS9.6 - Residential and therefore requires a tree unit density of 25 tree units per acre (FWRC 19.120.130-2). To calculate the total number of tree units required, the gross site acreage is multiplied by 25 (the required tree unit density based on land use designation). As such, the 0.43-acre parcel requires a total of 11 tree units to meet density requirements. Tree units must be maintained during and after development. Site development shall consider the location of existing healthy tree stands both on -site and on adjacent properties. Trees that are damaged, diseased, are a hazard, nuisance or invasive species shall not count towards tree retention requirements. Tree density requirements should be met primarily with the conservation of existing trees, however in situations where a development design would preclude the retention requirement, replacement trees may be authorized (FWRC 19.120.130-1). Table 4 summarizes tree unit credits for retention and replacement trees as required by Federal Way Revised Code. Due to the high overall tree count on the forested parcel, the existing tree unit credits currently far exceed minimum standards with 72.5 credits available (Table 5). Both trees proposed for removal are in poor (4) condition, and therefore do not contribute tree unit credits. As a result, the subject parcel is anticipated to maintain 72.2 tree credits during and after construction. Tree Inventory Report Afichuk Project October 2020 Page 7 Table 4. Tree unit credits (FWRC Table 19.120.130-2). Existing Tree Category Tree Unit Credit Existing Tree 1 " to 6" d.b.h. 1.0 tree units per tree retained Existing Tree > 6" to 12" d.b.h. 1.5 tree units per tree retained Existing Tree > 12" to 18" d.b.h. 2.0 tree units per tree retained Existing Tree > 18" to 24" d.b.h. Existing Tree > 24,, d.b.h. Replacement Tree Category Replacement Tree, Small Canopy Species (Mature canopy area < 450 SF) Replacement Tree, Medium Canopy Species (Mature canopy area 450 to 1,250 SF) 2.5 tree units per tree retained 3.0 tree units per tree retained .50 tree units per tree planted 1.0 tree units per tree planted Replacement Tree, Large Canopy Species (Mature canopy area > 1,250 SF) 1.5 tree units per tree planted Table 5. Tree unit credit calculations. Existing Tree Category Tree Count* Existing Tree 1 " to 6" d.b.h. 23 Existing Tree > 6" to 12" d.b.h. 5 Existing Tree > 12" to 18" d.b.h. 9 Existing Tree > 18" to 24" d.b.h. 6 Existing Tree > 24,, d.b.h. 3 TOTAL 46 T-ee Unit Credit Available 23 7.5 18 15 9 72.5 * Trees that are damaged, diseased, are a hazard, nuisance or invasive species shall not count towards tree retention requirements. Trees that were given a health rating of 4 (poor) or 5 (dying) are not included in the tree unit credit calculations table. All trees and vegetation proposed for retention shall be protected during construction according to the standards as outlined below in FWRC 19.120.160 Tree and vegetation protection during construction: Tree Inventory Report Afichuk Project October 2020 Page 8 (1) No clearing shall be allowed on a proposed development site until the tree retention and landscape plans have been approved by the city of Federal Way. (2) A no disturbance area shall be established for each tree to be protected. The no disturbance zone shall be equal to the critical root zone which is defined as 12 inches radius for every one inch of tree diameter measured at four and one-half feet above ground. Any other no disturbance area proposed by the applicant shall be determined by a qualified arborist and subject to review and approval by the director. (3) The no disturbance zone shall be identified during the construction stage with: (a) A temporary five-foot chain -link fence; and (b) Tree protection signage attached to the fence which reads "TREE PROTECTION FENCE — No soil disturbance, parking, storage, dumping, or burning of materials is allowed within the Tree Protection Fence." (4) No soil disturbance, parking, storage, dumping, burning of materials, impervious surfaces, fill, excavation, or storage of construction materials shall be permitted within the no disturbance area. (5) If the grade level around the tree is to be raised by more than one foot, a rock well shall be constructed. The inside diameter of the rock well shall be equal to the diameter of the tree trunk plus 10 feet. Proper drainage, and irrigation if necessary, shall be provided in all rock wells. (6) The grade level shall not be lowered within the larger of the drip line of the tree(s) or the critical root zone of the tree(s). (7) No trenching is allowed in any critical tree root zone areas. (8) No installation of any impervious surfaces is allowed in critical root zones. Where road or sidewalk surfaces are needed within critical root zones, unmortared porous pavers or flagstone (rather than concrete or asphalt) may be used. Boardwalks or bridging may span root zones without harming the tree roots. (9) Tree protection areas (i.e., critical root zone) must be prepared to better withstand the stresses of the construction phase by, if necessary, fertilizing, pruning, and mulching around them well in advance of beginning any construction activities. (10) Alternative protection methods may be used if accepted by the director to provide equal or greater tree protection. (11) Encroachment into the no disturbance area may be allowed where the director determines encroachment would not be detrimental to the health of the tree. Disclaimer The information contained in this letter is based on the application of technical guidelines currently accepted as the best available science and in conjunction with the manuals and criteria referenced above. All discussions, conclusions and recommendations reflect the best professional judgment of the author(s) and are based upon information available at the time the study was conducted. All work was completed within the constraints of budget, scope, and timing. The findings of this report are subject to verification and agreement by the appropriate local, state and federal regulatory authorities. No other warranty, expressed or implied, is made. Tree Inventory Report Afichuk Project October 2020 Page 9 Please call if you have any questions or if we can provide you with any additional information. Sincerely, Roen Hohlfeld Ecologist / ISA Certified Arborise PN-8562A Enclosures Tree Inventory Report Afichuk Project October 2020 Page 10 References Council of Tree & Landscape Appraisers. 2000. Guide for Plant Appraisal, 9th Edition. Chicago: International Society of Arboriculture. Tree Inventory Table - Stan Afichuck Table Issued: 10/29/2020 THE WATERSHED 1XX S 293rd Street - Federal Way, WA site visit: 7/1/2020 COMPANY parcel # 7202500080 1301 Alnus rubra (Red alder) 1 11.5 60 15 2 1302 Alnus rubra (Red alder) 1 10.8 60 12 2 1303 Alnus rubra (Red alder) 1 13.6 60 15 2 1304 Alnus rubra (Red alder) 1 14.5 60 15 2 1305 Alnus rubra (Red alder) 1 9.8 60 10 4 1306 Alnus rubra (Red alder) 1 11.6 60 15 3 1307 Alnus rubra (Red alder) 1 11.8 65 15 2 1308* Alnus rubra (Red alder) 1 10.7 25 5 5 Topped at 6 feet, regrowth. 1309 Alnus rubra (Red alder) 1 8.9 50 12 4 1310 Alnus rubra (Red alder) 1 9.1 55 15 4 1312 Alnus rubra (Red alder) 1 9.0 50 10 2 1313 Alnus rubra (Red alder) 1 16.0 55 20 2 1314 Alnus rubra (Red alder) 1 14.3 65 15 2 1315 Alnus rubra (Red alder) 2 16.4 65 25 3 1316* Acer macrophyllum (Bigleaf maple) 1 7.7 12 5 5 Topped at 6 feet, regrowth. 1317* Acer macrophyllum (Bigleaf maple) 1 6.7 12 5 5 Topped at 6 feet, regrowth. 1318* Acer macrophyllum (Bigleaf maple) 1 7.9 20 10 5 Topped at 6 feet, regrowth. 1321 Acer macrophyllum (Bigleaf maple) 3 30.3 25 12 5 Topped at 20 feet, regrowth. 1322 Acer macrophyllum (Bigleaf maple) 1 31.2 70 30 2 1323 Alnus rubra (Red alder) 1 6.2 50 15 4 1324 Alnus rubra (Red alder) 1 16.4 70 15 2 1325* Alnus rubra (Red alder) 1 15.5 70 15 2 1326 Acer macrophyllum (Bigleaf maple) 3 21.4 70 15 4 1327 Acer macrophyllum (Bigleaf maple) 3 22.1 60 15 4 1328 Acer macrophyllum (Bigleaf maple) 1 55.1 75 30 3 1329 Alnus rubra (Red alder) 1 23.0 75 20 2 1330 Alnus rubra (Red alder) 1 19.5 70 20 3 1331* Tsuga heterophylla (Western hemlock) 1 19.8 75 15 3 1332 Alnus rubra (Red alder) 1 18.0 80 20 3 1333 Acer macrophyllum (Bigleaf maple) 1 20.0 70 15 4 1334* Tsuga heterophylla (Western hemlock) 1 20.6 80 15 3 Limbed up 30 feet; climbing spike wounds. 1335* Tsuga heterophylla (Western hemlock) 1 24.6 80 15 3 Limbed up 30 feet; climbing spike wounds. 1336 Acer macrophyllum (Bigleaf maple) 2 15.5 65 20 4 Climbing spike wounds. 1337 Alnus rubra (Red alder) 1 20.9 75 15 3 Climbing spike wounds. 1338 Alnus rubra (Red alder) 1 23.6 70 20 3 Climbing spike wounds, partialy girdled. 1339 Alnus rubra (Red alder) 1 13.7 75 15 2 1340 Acer macrophyllum (Bigleaf maple) 1 9.3 8 8 5 Topped at 4 feet, regrowth. * Tree has not been surveyed; location is approximate. 750 6th Street South (425)822-5242 PAGE 1 OF 1 Tree Inventory Table (Off Parcel) - Stan Afichuck Table Issued: 10/29/2020 THE WATERSHED 1XX S 293rd Street - Federal Way, WA Site visit: 7/1/2020 COMPANY parcel # 7202500080 [TAG # 1 TIM. ....JJJJL� Alnus rubra (Red alder) 1 20.0 3 2 Alnus rubra (Red alder) 1 18.0 4 3 Alnus rubra (Red alder) 1 20.0 2 4 Tsuga heterophylla (Western hemlock) 1 16.0 3 5 Acer macrophyllum (Bigleaf maple) 1 12.0 3 6 Acer macrophyllum (Bigleaf maple) 1 10.0 4 7 Acer macrophyllum (Bigleaf maple) 1 24.0 2 8 Acer macrophyllum (Bigleaf maple) 1 24.0 3 9 Acer macrophyllum (Bigleaf maple) 1 8.0 3 10 Acer macrophyllum (Bigleaf maple) 1 36.0 3 11 Alnus rubra (Red alder) 1 10.0 3 12 Alnus rubra (Red alder) 1 10.0 3 13 Alnus rubra (Red alder) 1 10.0 3 14 Tsuga heterophylla (Western hemlock) 1 12.0 5 15 Acer macrophyllum (Bigleaf maple) 1 36.0 3 16 Acer macrophyllum (Bigleaf maple) 1 36.0 2 17 Tsuga heterophylla (Western hemlock) 1 12.0 2 18 Acer macrophyllum (Bigleaf maple) 1 16.0 3 19 Alnus rubra (Red alder) 1 14.0 2 1319 Acer macrophyllum (Bigleaf maple) 1 22.0 5 1320 Acer macrophyllum (Bigleaf maple) 1 22.0 5 750 6th Street South (425)822-5242 PAGE 1 OF 1 r 32 \ V 1321 /I I �36 1320 ,1 0 1 \\ 13191, \ ,ie 1318* PROPOSED DECK 1 � 1336\ ' \ I � 1 I 1335* / I 1337 I 17 � 1 TREE RETENTION AND REMOVAL PLAN SCALE 1:10 6 NOTES 1. TREE INVENTORY COMPLETED BY THE WATERSHED COMPANY ON JULY 1, 2020 (750 6TH STREET SOUTH; KIRKLAND, WA 98033; 425-9822-5242). SEE ARBORIST REPORT BY THE WATERSHED COMPANY (DATED AUGUST 17, 2020) FOR FURTHER DETAILS. 2. TREE NUMBERS WITH AN ASTERISK WERE NOT SURVEYED; LOCATION IS APPROXIMATE. 3. TREE PROTECTION FENCING IS SHOWN OFFSET FROM PROPOSED LIMITS OF DEVELOPMENT / CONSTRUCTION FOR VISUAL CLARITY PURPOSES ONLY. 4. SEE SHEET W8 FOR TREE RETENTION AND REMOVAL DETAILS. LEGEND EXISTING CONDITIONS PARCEL BOUNDARY DELINEATED WETLAND BOUNDARY APPROXIMATE WETLAND BOUNDARY DELINEATED OHWM STREAM BUFFER (35') SIGNIFICANT TREE PROPOSED CONDITIONS LIMITS OF DEVELOPMENT / CONSTRUCTION CRITICAL ROOT ZONE CRITICAL ROOT ZONE IMPACT TREE PROPOSED FOR REMOVAL (2) TREE PROTECTION FENCING A ws z 0 U OC (n Z O U OC O LL z w oc w 0' 5' 10, 20' 40' FVA i © 2020 - The Watershed Company 2 THE WATERSHED COMPANY 750 Sixth Street South Kirkland WA 98033 p 425.822.5242 www.watershedco.com Science & Design i Z U M Q LL J Q W W . o ~ o rn Z � z� < c) < O_cf)N3: �I C/) 0 C D �1 Q Q L �LLN W Q — U 0 U) 0� w LULU><<o � � X W OC Q r IL Q n W W rr W z O w �06 v J z J Q z O m U 0 J)P: o 2 O N H N_ Q 04 Q N O T 0 z T SHEET SIZE: ORIGINAL PLAN IS 22" x 34". SCALE ACCORDINGLY. PROJECT MANAGER: GB w z DESIGNED: RH U- DRAFTED: RH CHECKED: AMC, GB JOB NUMBER: m 191123 W z SHEET NUMBER: a W/ OF 8 a 0 TREE RETENTION AND REMOVAL TABLE TAG # TREE NAME LLIp '~ 2 m p � m _ O z u� .-. LL = W = LL p a oc z0 ~ O v N p W F_ O v O LLIp =a O v a W = cc O a u N m O LL p J LLI O O a = LU a oc 1301 Alnus rubra (Red alder) 1 11.5 60 15 2 1.5 Y - 1302 Alnus rubra (Red alder) 1 10.8 60 12 2 1.5 Y - 1303 Alnus rubra (Red alder) 1 13.6 60 15 2 2.0 Y - 1304 Alnus rubra (Red alder) 1 14.5 60 15 2 2.0 - - 1305 Alnus rubra (Red alder) 1 9.8 60 10 4 - Y - 1306 Alnus rubra (Red alder) 1 11.6 60 15 3 1.5 Y - 1307 Alnus rubra (Red alder) 1 11.8 65 15 2 1.5 Y - 1308 Alnus rubra (Red alder) 1 10.7 25 5 4 - Y Y 1309 Alnus rubra (Red alder) 1 8.9 50 12 4 - Y Y 1310 Alnus rubra (Red alder) 1 9.1 55 15 4 - - - 1312 Alnus rubra (Red alder) 1 9.0 50 10 2 1.5 - - 1313 Alnus rubra (Red alder) 1 16.0 55 20 2 2.0 - - 1314 Alnus rubra (Red alder) 1 14.3 65 15 2 2.0 - - 1315 Alnus rubra (Red alder) 2 16.4 65 25 3 2.0 - - 1316 Acer macrophyllum (Bigleaf maple) 1 7.7 12 5 5 - - - 1317 Acer macrophyllum (Bigleaf maple) 1 6.7 12 5 5 - - - 1318 Acer macrophyllum (Bigleaf maple) 1 7.9 20 10 5 - - - 1321 Acer macrophyllum (Bigleaf maple) 3 30.3 25 12 5 - - - 1322 Acer macrophyllum (Bigleaf maple) 1 31.2 70 30 2 3.0 - - 1323 Alnus rubra (Red alder) 1 6.2 50 15 4 - - - 1324 Alnus rubra (Red alder) 1 16.4 70 15 2 2.0 - - 1325 Alnus rubra (Red alder) 1 15.5 70 15 2 2.0 - - 1326 Acer macrophyllum (Bigleaf maple) 3 21.4 70 15 4 - - - 1327 Acer macrophyllum (Bigleaf maple) 3 22.1 60 15 4 - - - 1328 Acer macrophyllum (Bigleaf maple) 1 55.1 75 30 3 3.0 - - 1329 Alnus rubra (Red alder) 1 23.0 75 20 2 2.5 - - 1330 Alnus rubra (Red alder) 1 19.5 70 20 3 2.5 - - 1331 Tsuga heterophylla (Western hemlock) 1 19.8 75 15 3 2.5 - - 1332 Alnus rubra (Red alder) 1 18.0 80 20 3 2.0 - - 1333 Acer macrophyllum (Bigleaf maple) 1 20.0 70 15 4 - - - 1334 Tsuga heterophylla (Western hemlock) 1 20.6 80 15 3 2.5 - - 1335 Tsuga heterophylla (Western hemlock) 1 24.6 80 15 3 3.0 - - 1336 Acer macrophyllum (Bigleaf maple) 2 15.5 65 20 4 - - - 1337 Alnus rubra (Red alder) 1 20.9 75 15 3 2.5 - - 1338 Alnus rubra (Red alder) 1 23.6 70 20 3 2.5 - - 1339 Alnus rubra (Red alder) 1 13.7 75 15 2 2.0 - - 1340 Acer macrophyllum (Bigleaf maple) 1 9.3 8 8 5 - - - NOTES 1. SEE SHEET W7 FOR TREE RETENTION AND REMOVAL PLAN. 2. IMPACTS ARE NOT ANTICIPATED WITHIN CRITICAL ROOT ZONES OF SIGNIFICANT TREES LOCATED OFF -PARCEL. TREE RETENTION AND REMOVAL DETAILS FWMC 19.120.160 TREE AND VEGETATION PROTECTION DURING CONSTRUCTION (1) NO CLEARING SHALL BE ALLOWED ON A PROPOSED DEVELOPMENT SITE UNTIL THE TREE RETENTION AND LANDSCAPE PLANS HAVE BEEN APPROVED BY THE CITY OF FEDERAL WAY. (2) A NO DISTURBANCE AREA SHALL BE ESTABLISHED FOR EACH TREE TO BE PROTECTED. THE NO DISTURBANCE ZONE SHALL BE EQUAL TO THE CRITICAL ROOT ZONE WHICH IS DEFINED AS 12 INCHES RADIUS FOR EVERY ONE INCH OF TREE DIAMETER MEASURED AT FOUR AND ONE-HALF FEET ABOVE GROUND. ANY OTHER NO DISTURBANCE AREA PROPOSED BY THE APPLICANT SHALL BE DETERMINED BY A QUALIFIED ARBORIST AND SUBJECT TO REVIEW AND APPROVAL BY THE DIRECTOR. (3) THE NO DISTURBANCE ZONE SHALL BE IDENTIFIED DURING THE CONSTRUCTION STAGE WITH: (a) A TEMPORARY FIVE-FOOT CHAIN -LINK FENCE; AND (b) TREE PROTECTION SIGNAGE ATTACHED TO THE FENCE WHICH READS "TREE PROTECTION FENCE - NO SOIL DISTURBANCE, PARKING, STORAGE, DUMPING, OR BURNING OF MATERIALS IS ALLOWED WITHIN THE TREE PROTECTION FENCE." (4) NO SOIL DISTURBANCE, PARKING, STORAGE, DUMPING, BURNING OF MATERIALS, IMPERVIOUS SURFACES, FILL, EXCAVATION, OR STORAGE OF CONSTRUCTION MATERIALS SHALL BE PERMITTED WITHIN THE NO DISTURBANCE AREA. (5) IF THE GRADE LEVEL AROUND THE TREE IS TO BE RAISED BY MORE THAN ONE FOOT, A ROCK WELL SHALL BE CONSTRUCTED. THE INSIDE DIAMETER OF THE ROCK WELL SHALL BE EQUAL TO THE DIAMETER OF THE TREE TRUNK PLUS 10 FEET. PROPER DRAINAGE, AND IRRIGATION IF NECESSARY, SHALL BE PROVIDED IN ALL ROCK WELLS. (6) THE GRADE LEVEL SHALL NOT BE LOWERED WITHIN THE LARGER OF THE DRIP LINE OF THE TREE(S) OR THE CRITICAL ROOT ZONE OF THE TREE(S). (7) NO TRENCHING IS ALLOWED IN ANY CRITICAL TREE ROOT ZONE AREAS. (8) NO INSTALLATION OF ANY IMPERVIOUS SURFACES IS ALLOWED IN CRITICAL ROOT ZONES. WHERE ROAD OR SIDEWALK SURFACES ARE NEEDED WITHIN CRITICAL ROOT ZONES, UNMORTARED POROUS PAVERS OR FLAGSTONE (RATHER THAN CONCRETE OR ASPHALT) MAY BE USED. BOARDWALKS OR BRIDGING MAY SPAN ROOT ZONES WITHOUT HARMING THE TREE ROOTS. (9) TREE PROTECTION AREAS (I.E., CRITICAL ROOT ZONE) MUST BE PREPARED TO BETTER WITHSTAND THE STRESSES OF THE CONSTRUCTION PHASE BY, IF NECESSARY, FERTILIZING, PRUNING, AND MULCHING AROUND THEM WELL IN ADVANCE OF BEGINNING ANY CONSTRUCTION ACTIVITIES. (10) ALTERNATIVE PROTECTION METHODS MAY BE USED IF ACCEPTED BY THE DIRECTOR TO PROVIDE EQUAL OR GREATER TREE PROTECTION. (11) ENCROACHMENT INTO THE NO DISTURBANCE AREA MAY BE ALLOWED WHERE THE DIRECTOR DETERMINES ENCROACHMENT WOULD NOT BE DETRIMENTAL TO THE HEALTH OF THE TREE. CRITICAL ROOT ZONE OR OTHER LIMIT OF TREE PROTECTION AREA. SEE SHEET W7 FOR FENCE ALIGNMENT. 70d 8.5" x 11" SIGN LAMINATED IN PLASTIC SPACED EVERY 50' ALONG FENCE. TREE PROTECTION FENCING NOTES: 1. NO PRUNING SHALL BE PERFORMED UNLESS UNDER THE DIRECTION OF AN ARBORIST. 2. NO EQUIPMENT SHALL BE STORED OR OPERATED INSIDE THE PROTECTIVE FENCING INCLUDING DURING FENCE INSTALLATION AND REMOVAL. 3. NO STORAGE OF MATERIALS SHALL OCCUR INSIDE THE PROTECTIVE FENCING. 4. UNAUTHORIZED ACTIVITIES IN TREE PROTECTION AREA MAY REQUIRE EVALUATION BY PRIVATE ARBORIST TO IDENTIFY IMPACTS AND MITIGATION REQUIRED. 5. EXPOSED ROOTS: FOR ROOTS GREATER THAN 1" DAMAGED DURING CONSTRUCTION, MAKE A CLEAN, STRAIGHT CUT TO REMOVE DAMAGED PORTION AND INFORM CITY ARBORIST. TREE PROTECTION FENCE - CHAIN -LINK FENCING, STEEL POSTS INSTALLED AT 8' O.C. 5" THICK LAYER OF MULCH. MAINTAIN EXISTING GRADE WITH THE TREE PROTECTION FENCE UNLESS OTHERWISE INDICATED ON THE PLANS. Scale: NTS z 0 0� 0 LL 0 Z 1 W U) W © 2020 - The Watershed Company THE WATERSHED COMPANY 750 Sixth Street South Kirkland WA 98033 p 425.822.5242 www.watershedco.com Science & Design Z U M Q LL JQL� 00 o 1--I w O d Z0 � Z� < c) < O�C/) N 3: L 0 CO J �LLN L Q - U 0 U L w LU > C) O� X L Q r LL L m0� W z 0 w 06 z J J H O a �o m U 0 U H o 0 N W NO a Q N O T O z T SHEET SIZE: ORIGINAL PLAN IS 22" x 34". SCALE ACCORDINGLY. PROJECT MANAGER: GB w z DESIGNED: RH uj DRAFTED: RH CHECKED: AMC, GB JOB NUMBER: ca m 191123 W z SHEET NUMBER: a W8 OF 8W 0 Appendix D GEOTECHNICAL REPORT GEORESOURCES " ir0i `,{I fltf' gef.ite0lrmal cf rig irie-[ ri,it _-009� - 4809 Fadfic Hwy, E, I Fife. Washington 98424 1 253.896.1011 1 www- georesources.rocks Mr. Stan Afichuk 37237 42nd Avenue Southwest Auburn, WA, 98001 (206) 708-0065 Stan@greenbuilddev.com September 14, 2020 Geologic Hazard Assessment Proposed Single -Family Residence xxx South 293rd Street Federal Way, Washington PN: 720250-0080 Doc ID: AfichuckS.S293rdSt.GHA INTRODUCTION This updated report summarizes our recent site visit and observations, and updates our November 2017 report. We understand that you purchased the property from the previous owner but our November 2017 Geologic Hazard Assessment had not been submitted to the City. The 2017 report addressed potential geologic hazards for the proposed single-family residence to be constructed on the above referenced vacant parcel. The location of the site is shown on the attached Site Vicinity Map, Figure 1. Our understanding of the project is based on our discussions with you; our previous work on the adjacent parcel; our previous October 13, 2017 and November 28, 2017 site visits and our more recent August 14, 2020 site visit; and our understanding of the City of Federal Way critical areas ordinance (FWRC Chapters 19.05.070.G and 19.145). We understand that you propose to construct a new single-family residence in the upper portion of the subject parcel as shown on the attached Site Plan, Figure 2. According to the provided architectural elevation drawings, the garage floor elevation will generally be about the same elevation as S 293rd Street. The main floor will be half a story below the garage, while the upper floor will be half a story above the garage. There will be a daylight basement level below the main floor. We understand that the residence will be a three-story, wood -framed structure supported on conventional spread footings. However, because of the site slopes, deep foundations such as small diameter pin or needle piles, or drill piers, may be required in order to meet building setback requirements. The daylight basement retaining wall will be a cast -in -place concrete wall. A sewer lines is located in the central portion of the site and extends from a man -hole on the neighboring parcel to the south down to the mobile park on the north. The sanitary sewer easement is not shown on the site plan, but we understand that the easement is located entirely within the buffer. East of the sewer is a stream channel that also flows down to the north. We understand from our previous involvement on the adjacent parcel (including a Critical Areas Assessment and Stream Corridor Buffer report prepared by Habitat Technologies dated April 5, 2016). The Habitat Technologies report described the stream as an intermittent surface water drainage. The attached Afi c h u kS. 5293 rd St. G HA September 14, 2020 page 12 site plan indicates that there is a 50-foot stream buffer associated with the drainage. The buffer is shown on the attached Site & Exploration Plan, Figure 2. SCOPE The purpose of our services was to update our November 2017 report. Specifically, our scope of services for the project included the following: 1. Visiting the site and conducting a geologic reconnaissance to assess the site's soil, groundwater and slope conditions; and 2. Preparing this Updated Geologic Hazard Assessment per the City of Federal Way Critical Areas Ordinance for the proposed site development. We were verbally authorized by you to begin this update during our August 14, 2020 site visit. No new subsurface explorations were completed as part of this update. Since our initial site visits, the existing conditions appears relatively unchanged, with the vegetation becoming more established. Additionally, the house on the adjacent parcel to the south and east has been completed, whereas it was under construction during our last site visits. We previously prepared a similar Geologic Hazard Assessment for the adjacent residence (parcel 7202500070) to the south. The City had GeoDesign, Inc perform a third party review on the assessment and a revised assessment addressing the third party review was prepared on May 4, 2014. We understand that the revised assessment adequately addressed the review comments and was ultimately approved by the City. SITE CONDITIONS The subject parcel is located in the Redondo area of Federal Way, Washington. According to the provided site plan (included as our Site & Exploration Plan, Figure 2), the parcel is irregular in shape, generally measures about 167 to 140 wide (east to west) by about 130 to 216 feet long (north to south) and encompasses approximately 18,791 square feet. The parcel is bounded by South 293rd Street and an older residence on the west, by the aforementioned new residence on the south by a wooded, undeveloped area to the east, and by a mobile -home residential development on the north. The upland portion of the parcel, near the existing 293rd Street right of way, is flat to gently sloping. Approximately 6 to 8 feet north of the curb line, the site slopes steeply down (about 50 to 100 percent) over a vertical height of about 6 to 8 feet. We interpret this upper slope to be fill placed as part of the S 293rd Street road prism. The site flattens across a bench that slopes down at about 20 to 33 percent. Below the proposed house footprint, the site slopes steepen down to both the north and east to about 50 to 75 percent. The lower steep slope section extends down to an intermittent stream channel on the east and towards the mobile home park on the north. The slopes end in the stream channel and then slope back up to the east across a wooded slope. Total vertical relief across the site is on the order of 66 feet. The proposed location of the residence and site topography are shown on the attached Site & Exploration Plan, Figure 2. An aerial photograph of the site with topography obtained from the King County iMap website is included as the Site Vicinity Map, Figure 3. C,�0RrtsoL ROES Afi c h u kS. S293 rd St. G HA September 14, 2020 page 13 Vegetation on the site consists of tall grasses, blackberries, and both native and invasive brush. Some scattered young deciduous trees and occasional older fir trees are located along the north and east sides of the parcel. As discussed, shallow seasonal drainage course is located along the eastern property line. No springs or seepage was observed at the time of our site visit. No evidence of erosion, soil movement, landslide activity or deep-seated slope instability was observed at the site or the adjacent areas at the time of our site visit. During our previous site visits, we observed what was described by others to be tension cracks in the lower portion of the site. We had interpreted these cracks to be desiccation cracking that would be mitigated by the site development excavation. These tension cracks were not observed during our recent visit. Site Soils The Natural Resource Conservation Service (NRCS) Web Soil Survey maps the soils as Alderwood and Kitsap soils (AkF). The Alderwood and Kitsap soils are derived from glacial till, that form on 25 to 70 percent slopes. These soils are listed as having a "moderate to severe" erosion hazard a severe building limitation for slopes. These soils are listed in hydrologic soils group B/C. A copy of the SCS map for the site vicinity is attached as Figure 4. Site Geology The Geologic Map of the Poverty Bay 7.5-minute Quadrangle, Washington, Derek B. Booth, Howard H. Waldron, and Kathy G. Troost (2003) indicates the site underlain by coarse -grained older glacial deposits (Qpogc). These soils were generally deposited before the Vashon stade of the Fraser Glaciation, some 12,000 to 15,000 years ago. The glacial deposits typically consist of a heterogeneous mixture of clay, silt, sand and gravel that has been over ridden by the continental ice mass associated with the Vashon stade of Fraser glaciation. The glacial deposits are considered over -consolidated, are typically in a very dense condition, and exhibit high strength and low compressibility characteristics where undisturbed. Surficial soils are typically weathered to a loose to medium dense condition. No areas of landslides or mass wasting or noted on the map within the immediate vicinity of the site, however, a mass wasting deposit is shown on the map south and east of the parcel by about 500 to 600 feet. The mapped mass wasting deposit is on the east side of the stream channel valley from the site and immediately below an area of existing residential development. An excerpt of the above referenced map is included as Figure 5. The Washington State Department of Ecology Coastal Atlas for the site area indicates the flatter upland area to be "stable", while the slopes on the east side of the stream channel are mapped as "unstable". The unstable designation is likely attributed to the height and inclination of the slopes east of the streams. No areas of unstable recent or unstable historic landslides are shown on the Coastal Atlas within the site area. A copy of the Coastal Atlas map for the site area is attached as Figure 6. A series of oblique aerial shoreline photos obtained from the Coastal Atlas website are attached as Figures 7a through 7e. The photographs, taken between 1977 and 2016 show the site and adjacent areas. The three more recent photographs (1996, 2000, 2006) show the existing residential developments and site to be well vegetated. The 1977 shows the residential development below the site to be existing and the neighborhood that the site is located in to be under construction. G�C)R�sr�u��Es Afi c h u kS. S293 rd St. G HA September 14, 2020 page 14 Subsurface Conditions Two hand augers were excavated on the slope on the parcel to the south. We were also able to observed subsurface conditions as exposed on the active construction site to the south and as exposed in a root -ball hole from a large fallen tree on the south side of the subject property. In our opinion, the observed subsurface conditions generally confirmed the mapped stratigraphy. Similar to the soils encountered in the upper hand auger on the adjacent parcel, we anticipate that upper portion of the site soils has fill associated with construction of South 293rd Street and the sanitary sewer that cross the parcel. The soils encountered in our hand augers were characterized in accordance with the Unified Soil Classification System, a copy of which is attached as Figure 8. Logs of the test pits are attached as Figure 9. During construction of the house on the parcel to the south, old fill was encountered down about 4 to 6 feet below grade in the upper portion of the site. This was also observed with the fill encountered in the upper hand auger. Given the site grades, we anticipate the fill extends into the south portion of the subject site. GEOLOGIC HAZARDS The City of Federal Way Critical Areas Ordinance for Geologically Hazardous Areas state "geologically hazardous areas shall mean areas that, because of their susceptibility to erosion, landsliding, seismic or other geological events, are not suited to siting commercial, residential or industrial development consistent with public health or safety concerns." The Revised Code of Federal Way is copied in italics, while our comments to the code are immediately following the code. Erosion Hazard Areas per Federal Way Revised Code The FWRC, Chapter 19.05.070.G(1) defines erosion hazard areas as "those areas identified by the U.S. Department of Agriculture's (USDA) Natural Resource Conservation Service (NRCS) as having a moderate to severe or severe to very severe rill and inter -rill erosion hazard due to natural agents such as wind, rain, splash, frost action or stream flow; those areas containing the following group of soils when they occur on slopes of 15 percent or greater: Alderwood-Kitsap ('AkF'), Alderwood gravelly sandy loam ('AgD'9, Kitsap silt loam ("KpD'), Everett ("EvD'), and Indianola ("InD'9, and those areas impacted by shore land and/or stream bank erosion" The site soils are mapped as AkF, which have a severe erosion hazard when exposed. Conventional construction BMP's should be installed prior to beginning construction. This will provide adequate erosion control for the disturbed areas of the site. It is critical that the installed erosion control measures be monitored and maintained, and if necessary modified based on changing site conditions. In the event that the site is not worked for 7 days or more, the disturbed areas should be adequately erosion protected and maintained in the event of a significant storm event. This may include the use of plastic sheeting or mulch. Erosion control should specifically include the installation of silt fencing along the downslope and side slopes of the active construction area. Straw waddles and berms may also be necessary. We have not been provided with a copy of the proposed Temporary Erosion and Sediment Control (TESC) plan at this time. However, provided standard BMP's are installed prior to beginning construction, the potential for erosion or sediment leaving the site should be minimal. G, ORE'-�Cl4JRCE5 Afi c h u kS. 5293 rd St. G HA September 14, 2020 page 1 5 Landslide Hazard Areas per Federal Way Revised Code The FWRC, Chapter 19.05.070.G(2) defines landslide hazard areas as "those areas potentially subject to episodic downslope movement of a mass of soil or rock including but not limited to the following areas."These are typically characterized as having the following indicators: a. Any area with a combination of.• i. Slopes greater than 15 percent, ii. Permeable sediment overlying a relatively impermeable sediment or bedrock,• iii. Springs orgroundwaterseeps. b. Any area which has shown movement during the Holocene epoch, from 10,000 years ago to the present, or which is underlain by mass wastage debris of that epoch. c. Any area potentially unstable as a result of rapid stream incision, stream bank erosion or undercutting by wave action. d. Any area located in a ravine or on an active alluvial fan, presently or potentially subject to inundation by debris flows or flooding. e. Those areas mapped as Class U (unstable), UOS (unstable old slides), and URS (unstable recent slides) by the Department of Ecology's Coastal Zone Atlas. f. Areas designated as quaternary slumps, earthflows, mudflows, lahars, or landslides on maps published by the U.S. Geological Survey or Washington State Department of Natural Resources. g. Slopes having gradients greater than 80 percent subject to rockfall during seismic shaking h. Any area with a slope of 40 percent or steeper and with a vertical relief of 10 or more feet except areas composed of consolidated rock. A slope is delineated by establishing its toe and top and is measured by averaging the inclination over at least 10 feet of vertical relief. The site has slopes steeper than 15 percent, but no adverse or intersecting contacts are mapped on the site, nor were any seeps or springs noted on the slope or along the seasonal stream channel. No areas of mapped landslide debris or activity were noted on the published geologic map or Coastal Atlas. The stream channel is not deeply incised, and we anticipate that runoff from the developments along the west side of the stream channel have greatly decreased the amount of season flow, thereby reducing the potential for rapid stream incision or stream bank erosion. No areas of alluvial fans are mapped nor were any alluvial fans noted in the vicinity of the site at the time of our past site visits. The site is listed as being stable by the Department of Ecology Coastal Atlas, however the slopes on the east side of the stream are mapped as unstable because of their height and inclination. No areas of historic or recent landslide activity were identified on the Coastal Atlas. The site slopes are not steeper than 80 percent with and subject to rock fall during seismic shaking. Based on our observations and literature review, the site has one of the above indicators. The area is mapped as unstable on the east side of the stream channel, about 50 feet away from the proposed building site. While the site has one of the above indicators, it is our opinion that the proposed site development will mitigate the typical risks associated with steep slope site; grading of surficial disturbed/weathered soils, drainage and erosion control, therefore no additional buffer other than the stream buffer should be imposed by the City of Federal Way. As stated above, the steep slope below South 293rd Street appears to be part of the roadway prism. The lower bench and steep slope appears partially attributed to construction and installation of the adjacent sewer line installation. The flatter slope between these two steep slope areas does G�C)R�sr�u��Es Afi c h u kS. S293 rd St. G HA September 14, 2020 page 16 appear to be natural. As shown on the site plan, the house will be setback more than 7 feet from the north property and the steep slope that extends down to the adjacent mobile home park. This area will ultimately be retained by the daylight basement wall. Seismic Hazards per Federal Way Revised Code Earthquake -induced geologic hazards per City of Federal Way Revised Code (2016 FWRC), Chapter 19.05.070.G(3) may include liquefaction, lateral spreading, slope instability, and ground surface fault rupture. In our opinion, the potential for liquefaction and lateral spreading is not significant because of the dense nature of the on -site soils and the groundwater depth. Given the mapped stratigraphy of Pre -Olympia age gravel, which was overridden by the more recent Vashon stade of the Fraser Glaciation, it is our opinion that the potential for liquefaction is minimal. We interpret the structural site conditions to correspond to a seismic Site Class "D" in accordance with Chapter 20 of ASCE 20. This is based on the likely range of equivalent SPT (Standard Penetration Test) blow counts for the soil types observed in the site area. These conditions were assumed to be representative for the conditions based on our experience in the vicinity of the site. These soils are typically not prone to liquefaction and do not constitute a seismic hazard area. CONCLUSIONS AND RECOMMENDATIONS Based on our observations and site evaluations, it is our opinion as stated above, that the site meets technical criteria of an erosion hazard areas, but not that of a landslide or seismic hazard area. None -the -less, given the height and steepness of the site slopes, the Federal Way building department will require building setbacks from slopes steeper than 3H:1V (Horizontal:Vertical) per the International Building Code (IBC) section 1805. Recommended Setback The IBC requires a building setback from slopes that are steeper than 3H:1V (Horizontal: Vertical) unless evaluated and reduced, and/or a structural setback is provided, by a licensed geotechnical engineer. The setback distance is calculated based on the vertical height of the slope. The typical IBC setback from the top of the slope equals one third the height of the slope. Using the IBC Setback criteria and given the vertical height of the slope below the proposed daylight basement residence has a vertical height of about 40 feet. This would require a setback from the steep slope area of about 17 feet. As currently proposed, the residence will be setback about 5 feet from the top of the steep slope area. Where the setback cannot be met, the IBC allows for a "structural setback' where foundation elements are extended vertically and the setback distance is measured from the base of the deepened foundation element to the face of the slope at the corresponding elevation. Given the slope below the house, we estimate foundation elements will need to be extended a minimum of about 7 feet along the east side of the residence. A detail showing the structural setback configuration is attached as Figure 10. Storm Drainage Based on the results of our shallow subsurface explorations and sloping nature of the site, infiltration of collected stormwater runoff is not feasible. Based on our discussions, we understand G�C)R�sr�u��Es Afi c h u kS. S293 rd St. G HA September 14, 2020 page 1 7 that roof and driveway runoff will be directed back to South 293rd Street, while the footing and basement wall drains should be tightlined to discharge into the stream corridor below the proposed residence. Since no seepage was noted on the upper of the site slopes, the amount of water discharging from the footing and wall drains should be minimal. LIMITATIONS We have prepared this report for Mr. Stan Afichuk and other members of the permitting and design team for use in evaluating a portion of this project. Subsurface conditions described herein are based on our observations of exposed soils on the parcel. This report may be made available to regulatory agencies or others, but this report and conclusions should not be construed as a warranty of subsurface conditions. Subsurface conditions can vary over short distances and can change with time. Variations in subsurface conditions are possible between the explorations and may also occur with time. A contingency for unanticipated conditions should be included in the budget and schedule. Sufficient monitoring, testing and consultation should be provided by our firm during construction to confirm that the conditions encountered are consistent with those indicated by the explorations, to provide recommendations for design changes should the conditions revealed during the work differ from those anticipated, and to evaluate whether earthwork and foundation installation activities comply with contract plans and specifications. The scope of our services does not include services related to environmental remediation and construction safety precautions. Our recommendations are not intended to direct the contractor's methods, techniques, sequences or procedures, except as specifically described in our report for consideration in design. If there are any changes in the loads, grades, locations, configurations or type of facilities to be constructed, the conclusions and recommendations presented in this report may not be fully applicable. If such changes are made, we should be given the opportunity to review our recommendations and provide written modifications or verifications, as appropriate. G�C)R�sr�u��Es AfichukS.S293rdSt.GHA September 14, 2020 page 1 8 We have appreciated working for you on this project. Please do not hesitate to call at your earliest convenience if you have any questions or comments. Respectfully submitted, GeoResources, LL Keith S. Schembs, LEG Eric W. Heller, PE, LG Principal Senior Geotechnical Engineer KSS:EWH:kss Doc ID: AfichuckS.S293rdSt.GHA Attachments: Figure 1: Site Location Map Figure 2: Site & Exploration Plan Figure 3: Site Vicinity Map Figure 4: NRCS SCS Soils Map Figure 5: Geologic Map Figure 6: Coastal Atlas Figures 7a through 7e: Oblique Shoreline Photographs Figure 8: Soil Classification System Figure 9: Hand Auger Logs Figure 10: Structural Setback GV0RES0LJRC'ES Puget Sound S 2P9TH yl i S _,_ ST Des Moines ,Ltb'otenfPark / S kL s �k sr sw 2R+a ST SW MNEST s 239Ro FL SW 25di1f 57 � O VL S 295N SW 2TTTH ST . S 29HTH PL 2WTN sT � S 29TT>H Sr uy StiV 29UrI?PL W 299Tx ST 'c a Sri In sw 3UT+i ST d' s w 3ww ST SwTrr s � � w sansrxsT y4 w 4 Q w w 7 s 9o9rrr ST ff-' {�r KI ifl Iwo Sti,V 30BTN Sl $ S3f A w0. 1 a rh S>. S 293RD ST ' 40" N S A GJ 4 T 4 Federal Way wjawea� Park � s3orr.rST�� L` w S 307U ST 6 4 � q S 3¢aqfr ST s aocni sT ST 0 q 5 2i9T�I ST 4 SLLL„,fir FL 9 jIvT s � S 29ii}{ si w _ S2Wpq a +q1 S�7Tk A{' Ik b w S 2WT- i ST r S S 297 tt ST +sr w d a � 5 44 w q�' Laore�wood. ark �'•` 1 S "Tk VF All w s 29•irdr q S 2M'f�r Si s 2WR1 - w k S"Th ST N r4 � ' � g.�1.�1T S a71Siq `w i � I w w d e d Approximate Site Location L R L S U E eartrl science & geotechnl{ai eng;neeririg Q@q v.acmt Fs.q E. I Flr.- WA W4?a 1753.a".t-Qi 1 I vi". 2r4r"QVrCg5.Wk: Sfeet Lake / ; Stem take Park -V 4 �7 A ,I N a Site Location Map Proposed Single -Family Residence xxx South 293rd Place Federal Way, Washington Sa s 29HTN ST g 2gTH 6i 3 340r, F? s al2ka PL Not to Scale L Scale 1^=30' 0 151 30, 60, Site Plan prepared bv Urban Architecture dated 5/22/2020 1b SL,1 m Soil Log Number and Approximate Location (unknown) HA'1 Hand Auger Log Number and Approximate Location (adjacent parcel, GeoResources'2O12) 0' -~ NOE HA-1 � 000 . - 0 0 On �M.M�_Mw G E 0 R E S 0 U R C E S earth ac|ence& geotechnicalemg|meer|mg Site & ExKDU��rat^��n Plan " Proposed Single -Family Residence xxxSouth 293mPlace Approximate Site Location (map created on King County iMap website: http://www.kingcounty.gov/operations/gis/Maps/iMAP.aspx) mom, GEORESOURCES earth science & gectechnicak engineering LBO 9acIflc Fr-y E. I Flta WA M d?a I 251.846.tat1 I w w, gt �rg;o�rcac,r�eks Site Vicinity Map Proposed Single -Family Residence xxx South 293rd Place Federal Way, Washington Not to Scale Approximate Site Location (map created from the USDA Natural Resource Conservation Service Web Soil Survey) Soil Soil Name Parent Material Slopes Erosion Hazard Hydrologic Type Soils Group AkF Alderwood Kitsap Formation Glacial Till /Outwash 25 to 70 Moderate/Severe B w4—V: GEORESOURCES earth science & geotechni�a, engineering LO" Pacific hwy e. I Faro-_ WA M44 01 1 fly 1 1 www, 2tgrg:9urroa.1focki NRCS SCS Soils Map Proposed Single -Family Residence xxx South 293rd Place Federal Way, Washington Not to Scale - I I Wb Gfrk y i TT310 t Wt IF Approximate Site Location An excerpt from the Geologic Map of the Poverty Bay 7.5-minute Quadrangle, Washington by Booth, Howard, and Troost, 2003 N - Not to Scale Geologic Map Proposed Single -Family Residence GEORESOURCES xxx South 293rd Place earth sderice & geotechriical engineering Federal Way, Washington Qn �i[IQc Ftwj. E, I Flh. 4yA 464#i I i53,�44.iUi7 i w.vw, gt lrB;41,r{�f,rOEkc Doc: AfichuckS.S293rdSt.F September 2020 Figure 5 7 a 1 + 1i 4�, r � 5r• v9.. w .� r� r c +'s4 C. ;� z 1 y•slr . L ' 292W r � 1 - . * YJ • � � rcr J: .,• ilirylL I ,i��i�a f, r. _ r Approximate Site Location Map created at Washington State Department of Ecology Coastal Atlas Website (httpsJ/fortress. wa.gov/ecy/coastalatlas/tools/Map. asp) 0 Slap$ stability 0 StabEa �� InE�rm�diaF�e Modified Unstable Unstable {#Id sEdde) UnsEnblc (rrcmnt !lidm) G E E S E S earth scierlce & geotechnica i_ngineering "N Ga�lilc Er.Yy. E. I Flh_ WA U4 L 1 7510%.i]t 1 i www, gtgrg;q�r��c,r�rks Not to Scale Coastal Atlas Proposed Single -Family Residence xxx South 293rd Place Federal Way, Washington Doc: AfichuckS.S293rdSt.F September 2020 Figure 6 Approximate Site Location Photo taken 7/29/2016 and obtained from the Washington State Department of Ecology Coastal Atlas Website (https://fortress. wa.gov/ecy/coastalatlas/tools/Map. asp) GEORESOURCES earth science & geoteehnicat engineering MN,Pacinc Fray E. I Flrr_ WA M44 d I 753.I 6.tliI I w . gr4rB;4Wrc".F4 kG Oblique Shoreline Photographs Proposed Single -Family Residence xxx South 293rd Place Federal Way, Washington Approximate Site Location Photo taken 7/26/2006 and obtained from the Washington State Department of Ecology Coastal Atlas Website (httpsJ/fortress. wa.gov/ecy/coastalatlas/tools/Map. asp) GEORESOURCES earth science & geotechnical engineering Q44 Ra[Int KwV. E. I ilft_ WA M4x& I I www, $� FeB;O�rraa,rarkc Oblique Shoreline Photographs Proposed Single -Family Residence xxx South 293rd Place Federal Way, Washington Approximate Site Location Photo taken 9/25/2006 and obtained from the Washington State Department of Ecology Coastal Atlas Website (httpsJ/fortress. wa.gov/ecy/coastalatlas/tools/Map. asp) who. EOIESOES earth science & geotechnicai engineering AMA ,'a{iilr Fray E. I Fldo-_ WA M4 %A 1 ♦ 11 1 www. gonrg;qurraa.rark% Oblique Shoreline Photographs Proposed Single -Family Residence xxx South 293rd Place Federal Way, Washington Approximate Site Location Photo taken 5/19/1993 and obtained from the Washington State Department of Ecology Coastal Atlas Website (https.//fortress. wa.gov/ecy/coastalatlas/tools/Map. asp) GEORESOURCES e-: .- science & geotec hn icai eng+neering k8f+P BQ�iic H q E. I Flit_ WA. M4?11 1 1 1 v w. poeejourfPs.ve6s Oblique Shoreline Photographs Proposed Single -Family Residence xxx South 293rd Place Federal Way, Washington AL Pjl . 9m - -{ SOIL CLASSIFICATION SYSTEM MAJOR DIVISIONS GROUP GROUP NAME SYMBOL GRAVEL CLEAN GW WELL -GRADED GRAVEL, FINE TO COARSE GRAVEL GRAVEL COARSE GP POORLY -GRADED GRAVEL GRAINED More than 50% SOILS Of Coarse Fraction GRAVEL GM SILTY GRAVEL Retained on WITH FINES GC CLAYEY GRAVEL No. 4 Sieve SAND CLEAN SAND SW WELL -GRADED SAND, FINE TO COARSE SAND More than 50% SIP POORLY -GRADED SAND Retained on No. 200 Sieve More than 50% Of Coarse Fraction SAND SM SILTY SAND Passes WITH FINES No. 4 Sieve SC CLAYEY SAND SILT AND CLAY INORGANIC ML SILT FINE GRAINED CL CLAY SOILS Liquid Limit Less than 50 ORGANIC OL ORGANIC SILT, ORGANIC CLAY SILT AND CLAY INORGANIC MH SILT OF HIGH PLASTICITY, ELASTIC SILT More than 50% Passes CH CLAY OF HIGH PLASTICITY, FAT CLAY No. 200 Sieve Liquid Limit 50 or more ORGANIC OH ORGANIC CLAY, ORGANIC SILT HIGHLY ORGANIC SOILS PT PEAT NOTES: 1. Field classification is based on visual examination of soil in general accordance with ASTM D2488-90. 2. Soil classification using laboratory tests is based on ASTM D2487-90. 3. Description of soil density or consistency are based on interpretation of blow count data, visual appearance of soils, and or test data. EOI ESOU CES earth science & geotccrrnlca %�ngirleeTing LBO aacinr Fl%wr E. I Flrt_ WA N44 d I I I w w, SoOr9;9,rrac,eaek.: SOIL MOISTURE MODIFIERS: Dry- Absence of moisture, dry to the touch Moist- Damp, but no visible water Wet- Visible free water or saturated, usually soil is obtained from below water table Soil Classification System Proposed Single -Family Residence xxx South 293rd Place Federal Way, Washington Hand Auger HA-1 Location: Upper west central portion of site Approximate Elevation: 276 feet Depth (inches) Soil Type Soil Description 0 - 6 - Topsoil 6 - 24 - Dark Orange -brown silty fine to medium SAND with gravel, some , asphalt (loose to medium dense, mosit)(fill) 24 - 36 SM Orange -brown silty fine to medium SAND with gravel (medium dense, moist)(weathered till) Terminated at 36 inches No caving observed. No groundwater seepage observed. Hand Auger HA-2 Location: East central portion of site, above stream channel Approximate Elevation: 270 feet Depth (inches) Soil Type Soil Description 0 - 4 - Topsoil 4 - 22 - Dark Orange -brown silty fine to medium SAND with gravel, some wood (loose to medium dense, moist)(weathered till/fill?) 22 - 42 SM Orange -brown silty fine to medium SAND with gravel (medium dense, moist)(weathered till) Terminated at 42 inches No caving observed. No groundwater seepage observed. KSS Excavated on: June 15, 2012 Hand Auger Logs Proposed Single -Family Residence xxx South 293rd Place earth scieriee & geotechnical eng:neerlf3 Federal Way, Washington M" FaCific Fray F. i Mirk WA M4?d i i www, $tgrg;0�rraa,rarkc Doc: AfichuckS.S293rdSt.F I September 2020 1 Figure 9 Conventional Footing Slopes Greater Than 30 Percent Slopes Greater Than 30 Percent Setback Distance Footing Extension Setback Distance GEORESOURCES earth science & geotechnirai engineering Loop Racinc wr E. I Flrr_ WA Mid?a I I wow. ZPor@iokdreiPs.F4[ka Deck Post Foundation Foundation Element Foundation Footing Extension Foundation Element Not to scale Structural Setback Proposed Single -Family Residence xxx South 293rd Place Federal Way, Washington