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08-105536CITY OF A. Federal December 23, 2008 SNR Company Attn: Steven Neugebauer 15211 P Place NE Duvall, WA 98019 CITY HALL 33325 8th Avenue South y Mailing Address: PO Box 9718 Federal Way, WA 98063-9718 (253) 835-7000 www.cityoffederalway.com RE: File #08-105536-00-AD; BENJAMIN Parcel #119600-2544 Dear Mr. Neugebauer: This letter is in response to your inquiry submitted to the city on November 13, 2008, regarding the status of what the city classified as a Class III Wetland on Parcel #119600-2544. The SNR Company's field analysis of the wetland (originally dated September 27, 2007) concluded that the wetland's hydrology was delivered to the site by means of an offsite sanitary sewage source. Third party lab tests (conducted by Spectra Laboratories) of the hydrology of the wetland confirms that the wet area was a result of a sanitary sewer leak in the vicinity based upon the high levels of fecal coliform bacteria, boron, and nitrate found in the soil samples. We will forward this finding to the Graphic Information Services (GIS) division and have the wetland classification disassociated with parcel #119600-2544. If you have any further questions, please feel free to contact me at 253-835-2622 or e-mail me at david.lee@cityoffederalway.com. Sincerely, Davtd Lee Associate Planner c: Erik Earle, GIS Analyst Doe. I D 48143 David Lee From: Nick Geise [nickg@spectra-lab.com] Sent: Tuesday, December 16, 2008 11:46 AM To: David Lee Subject: RE: Townsend Property Project Good morning, David. Everything checks out on our end. 1. Spectra is an independent lab, unaffiliated with the SNR Company 2. We performed analysis for said company listed under Spectra Project # 2007080461 3. Results for this project were signed off by laboratory manager, Steve Hibbs on 9/12/2007 Don't hesitate to contact us if you have any further questions. Thank you! Sincerely, Nicholas Geise Nicholas J. Geise Sample Management/Client Services SPECTRA Laboratories 2221 Ross Way Tacoma, WA 98424 Phone: (253) 272-4850 Fax: (253) 572-9838 www.saectra-lab.com n i ckg@saecl:ra-lab. corn From: David Lee [mailto: David. Lee@cityoffederalway.com] Sent: Tuesday, December 16, 2008 11:14 AM To: Nick Geise Subject: Townsend Property Project Good Morning, My name is David Lee and I'm a planner for the City of Federal Way. The SNR Company submitted to the city a wetland classification report for the Townsend Property. And in it, it references lab work for the water sample done by your company (Spectra Project# 2007080461). 1 just need to verify that Spectra Labratories is an independent lab and unaffiliated with the SNR Company and that the Spectra Project# 2007080461 is a valid project number. If it helps any, it seems that the the lab findings were signed off by Steve Hibbs on 9/12/2007. If you have any questions, please feel free to e-mail me at david.lee@cityoffed_eralway.com or call me at (253) 835-2622. Thank you very much for your time. Sincerely, David Lee David Lee Associate Planner City of Federal Way [0] (253) 835-2622 [F] (253) 835-2609 david.lee @ cityoffede ra €way.co m F f:''EIVED BY COMMUNITY C .OPMENT DEPARTMENT Nov 13 2008 ENVIRONMENTAL, ECOLOGICAL, HYDROGEOLOGY, AND ENGINEERING SNR Company GEOLOGY CONSULTANTS November 7, 2008 Mr. Isaac Conlen Planning Manager Planning Department City of Federal Way 33325 8th Ave S PO BOX 9718 Federal Way, WA 98063-9718 Project Number: 05-07-007 RE: Request for Reclassification of Wetland Identified to be present by the City of Federal Way on King County Parcel Number 1196002544; City File Number 06-101080 Dear Conlen: The attached letter report' is a copy of what SNR sent to Ms. Debbi Barker in the Federal Way Planning Department. This letter was supplemental to a report that SNR prepared for Dr. Bent Benjamin (Benjamin), Letter Report — Wetland Buffer Restoration Plan Benjamin Retaining Wall King County Parcel number 1196002267, USPS address of 29435 10th Avenue SW, Federal Way, WA 98023. The first document was prepared by SNR Company for Dr. Benjamin. This document indicated that based on SNR's observations of the "wetland" area on the Townsend property, the hydrology appeared to be derived from manmade sources and that the area was too small to rate per the City of Federal Way Critical Areas Ordinance and per the Washington State Wetland Rating Manual for Western Washington. At the request of Mr. Townsend, SNR had been conducting other studies on his properties located in this area, including ground water studies. These ground water studies included studies of water quality and the source of the seeps that were providing the hydrology for the "wetland area". Additionally, Dr. Benjamin retained SNR to conduct a more detailed survey of the wetland area to see if the wetland boundaries could be relocated if SNR delineated the boundary using soils as the indicator factor. Dr. Benjamin and Mr. Townsend also requested that SNR delineate the entire wetland boundary so the size of the potential wetland area could be surveyed and the area calculated. The ground water and additional wetland studies conducted by SNR and the surveying of the wetland boundary markers have allowed SNR to make the following conclusions: 1) The wetland hydrology is derived from a manmade source, this source water is impacted with coliform bacteria, including e.coli species, which means it is likely derived from a sanitary sewage source. This ground water also contains boron and nitrates that do not occur naturally in any ground water found in this area of Federal Way further indicating that the source is from sanitary sewage. 2) By conducting calculations on the surveyed wetland boundary, SNR has determined that this area is approximately 2,203 square feet, which would be too small to rate even if the hydrology were naturally occurring wetland hydrology. 1 Supplemental Letter Report to Letter Report —Wetland Buffer Restoration Plan -Benjamin Retaining Wall, April 3, 2007 29435 10th Avenue SW. Federal Way, WA - King County Parcel #1196002267 - File #06-101079-00-UP, Additional Information Requested, Rev. 1 15211 311 PLACE NE • DUVALL, WA • 98019-8370 PHONE: 425-788-3015 • CELL: 206-291-5556 WWW.SNRCOMPANY.COM Client Name: PH & TF Townsend Trust Project Number. 05-07-007 Project Name: Wetland Reclassification or Removal of Designation — Townsend Property, Federal Way November 7, 2008 3) The seeps that are the source of the water that created the environment that appears to be a wetland area, are apparently derived from a sanitary sewer source and this water contains anaerobic bacteria and nutrients (nitrates) that have created a reducing environment within the artificially recharged perched aquifer (as determined by test pits excavated south of the seep area and piezometers that have been installed on the Townsend property) which is causing iron reducing bacteria to grow and is further impacting the water quality. Because there is no naturally occurring wetland hydrology present and the area of the artificial wetland habitat is too small to rate, it is SNR's opinion that the City should remove the wetland area the City's Critical Areas Map shows to be present on the Townsend property (see attached) to either a non -wetland area or a non -ratable wetland area with no critical areas restrictions. Additionally, as discussed in SNR's supplemental report, there is no naturally occurring stream on the Townsend property or any of the properties in the immediate vicinity of the Townsend property. The small amount of water that is derived from the seeps derived from sanitary sewage is not natural and will hopefully be stopped as soon as the source of the water is identified and source can be eliminated. Ms. Barker issued the permit for Dr. Benjamin to construct a soldier pile wall on his property with no critical areas restrictions associated with the temporary access road that was necessary to build this wall. The decision to not require mitigation for the temporary road was based on Ms. Barker's review of the attached report. Further, Ms. Barker advised Mr. Townsend that to proceed to the next step for removing the wetland shown on the City's Critical Areas Map was to submit this formal request. Therefore, SNR is making this request on the behalf of Mr. Townsend, that the City revise the City of Federal Way's Critical Areas map to remove the wetland area shown on Mr. Townsend's property and to amend the wetland designation in the City's critical areas listings for the wetland shown to be on the Townsend property. If you have any questions or require more information, please contact me at your convenience. Sincerely, SNR COMPANY, LLC Steven F. Neugebauer— LG, LHG, LEG, REA Principal Hydrogeologist Cc: Mr. Peter Townsend Attachments: Excerpt from City of Federal Way Critical Areas Map Bound Supplemental Letter Report to Letter Report — Wetland Buffer Restoration Plan - Benjamin Retaining Wall, April 3, 2007 29435 10th Avenue SW, Federal Way, WA - King County Parcel #1196002267 - File #06-101079-00-UP, Additional Information Requested, Rev. 1 OsNR Company Client Name: PH & TF Townsend Trust Project Number: 05-07-007 Project Name: Wetland Reclassification or Removal of Designation — Townsend Property, Federal Way November 7, 2008 MW EVA oil Ai#,Alt IN �OW— V A ~ - 8SNF1 Company RECE1VED BY COMMUNITY DEVEI IENT DEPARTMENT NOV 3 Z008 ENVIRONMENTAL, ECOLOGICAL, HYDROGEOLOGY, GEOTECHNICAL ENGINEERING AND ENGINEERING GEOLOGY CONSULTANTS September 27, 2007 Dr. Brent Benjamin, MD 29435 101h Avenue Southwest Federal Way, Washington 98023 Mr. Peter Townsend, CPA Trustee PH & TF Townsend Trust 1648 S 310th, Suite 6 Federal Way, WA 98003 RE: Supplemental Letter Report to Letter Report - Wetland Buffer Restoration Plan - Benjamin Retaining Wall, April 3, 2007 29435 10th Avenue SW, Federal Way, WA - King County Parcel #1196002267 - File #06-101079-00-UP, Additional Information Requested Gentlemen: Each of you has requested additional studies to be conducted on the Townsend Trust property (King County Parcel Number 1196002544 - Subject Property) by SNR Company. The additional studies include: See if the eastern "wetland" boundary can be adjusted and identify/delineate the "wetland" area's western boundary using more detailed field methods. • Conduct studies of the groundwater and seep area ■ Investigate the source of the surface water in the relic channel, and s Determine the size of the "wetland" area. Mr. Peter Townsend, CPA, is the trustee of the trust that owns the subject property where the "wetland area" and "stream" are located; a vacant property, King County Parcel Number 1196002544 (Figure 1 - Site Location Map). Dr. Brent Benjamin, MD, owns the property located east of the Townsend property, a property developed with a single family dwelling, King County Parcel Number 11996002267. This property must have a soldier pile wall constructed to prevent potential ground movement in the northern portion of the property. A temporary access road must be built to install this wall. This access road was believed to possibly pass through a "wetland" buffer area. If this were the case, a 152113 d Place NE * Duvall, WA 98019 425-788-3015 + 206-291-5556 (Cell) www.snrcompany.com Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 wetland restoration plan would be required. To determine if this plan was required, the eastern "wetland" boundary had to be determined to establish where the eastern "wetland" buffer boundary was located. The initial "wetland" boundary determination was based on the assumption that there was a Category 3 wetland present and did not include detailed soils and hydrology studies. The supplemental studies did include detailed soils and hydrology studies, which resulted in some of the boundary area being moved to the west. These supplemental studies also included the identification and delineation of the "wetland" western boundary, which was staked and flagged also. This supplemental report includes the resurveyed "wetland boundary" map, but the size of the potential wetland area is also discussed. As discussed in this document, due to the small size of this area, even if a true wetland were present, it would be too small to be rated and regulated as a wetland area (less than 2,500 square feet). SNR's activities also included detailed studies of the hydrology and hydrogeology of the area, including the nature and origin of the seep areas that contribute to a small drainage course that can extend up to 190 feet from the seep area to the north in the relic drainage channel. The City has requested SNR to determine if this drainage course could be a minor stream. Based research, field studies, and SNR's observations of this area for almost six months, SNR has determined that: 1. There is no wetland area present on the subject property. 2. There is no classifiable minor stream located on the subject property or the other properties to the north. 3. The ground water that is responsible for the seep area includes nuisance water that is derived from manmade sources including sanitary sewer systems. 4. The storm water that is discharged into the relic channel area is discharged north of the seep area and is derived from single family residence drive area drains located to the east and is not considered to be a significant source and therefore does not require an NPDES permit. 5. Since there is no wetland area present, there is no wetland buffer area and therefore the activities to build a temporary access road for the construction of the Benjamin soldier pile wall will not require a buffer restoration plan. N a� a 29435 JOT" AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report- Revision 1 SNR Company, Environmental Consultants u_U, Zwr Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 6. Since there is no ratable wetland area located on the subject property there should be no critical areas restrictions on this property or any other properties located in the vicinity of the subject property. 7. Since there is no classifiable minor stream present, there should be no critical areas restrictions on the subject property or those properties located in the vicinity of the subject property. The following sections of this supplemental letter report will discuss the studies that have been conducted, the findings from these studies, and includes SNR's conclusions and recommendations. Figure 1 — Site Location Map 3 - i • FFr AREA ��-• M r � m ] 9 cM 4) CIO IL 29435 10TN AVE SW, FEDERAL WAY - PARCEL #1196002267 Supplemental Letler Report- Revision i © SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 1.0 EXECUTIVE SUMMARY As discussed in SNR's April 3, 2007 Letter report, the "wetland area" did not appear to meet the three requirements for it to be delineated as a wetland (naturally occurring hydric soils, wetland hydrology, and assemblages of hydrophytic vegetation), additionally, it was believed that this area was too small to rate even if it were a wetland area. The purpose of the first study was to determine where the wetland buffer area extended to in the eastern portion of the wetland area and to develop a Wetland Buffer Restoration Plan. SNR did conduct a wetland boundary survey and stake the 'wetland" boundaries to the east based on the assumption that a Category 3 wetland was present; however, because there was no surveyed location of the proposed temporary access road that would be constructed to allow the construction of a soldier pile wall on the Benjamin property, SNR could not develop a restoration plan because SNR did not know how far the proposed road would extend into the buffer area. SNR placed a series of wetland boundary stakes based on saturated soils and where hydrophytic vegetation was present only. No detailed soil investigation was conducted because this was not included in the scope of work. The establishment of the wetland buffer areas is usually established by the surveyor who surveys the locations of the wetland boundary markers, to ensure accurate placement of this buffer area from the wetland boundary area. However, to provide a general idea of where the wetland buffer boundaries would be located SNR taped off the appropriated distance from the wetland boundary stakes and installed these "temporary" wetland buffer boundary stakes. It was anticipated that the wetland boundary stakes would eventually be surveyed and the wetland buffer stakes would be repositioned to their appropriate locations based on the survey information. It was noted in the April 3, 2007 letter report that the stakes and the area must be surveyed before the true wetland buffer boundaries could be located and the location of the proposed temporary road must be depicted before a wetland buffer restoration plan could be prepared. This report also indicated that a true wetland identification and delineation was not conducted and that SNR suspected that the hydrology was associated with nuisance water and was not natural. We also suggested that the "wetland" area was most likely too small to rate, but without survey data could not submit this finding to the City of Federal Way. Dr. Benjamin arranged to have the wetland area and the wetland boundary stakes surveyed to determine an accurate location for the wetland boundary and to provide an accurate base map to depict the proposed location of the 'I - temporary access road. CO 29435 LOTH AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report- Revision 1 SNR Company, Environmental Consultants LLU, Zuu( Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 Because the survey would be conducted on the subject property, Dr. Benjamin had discussions with Mr. Townsend to obtain permission to have the survey conducted. At this time Mr. Townsend suggested that a more detailed wetland investigation may provide information that might affect the original wetland boundary locations initially established by SNR. Mr. Townsend also indicated that he would like to have the western boundary of the wetland area delineated so it could also be surveyed and the size of the wetland area could be determined accurately. After having several communications between Dr. Benjamin, Mr. Townsend, and SNR, it was decided to see if a more detailed wetland investigation would allow some of the wetland boundary stakes to be relocated further west from the structures on the Benjamin property, SNR conducted a more detailed wetland investigation in the "wetland" area on July 18, 2007. This investigation included a detailed field investigation of the soils to determine the hydric soil boundaries with these studies including the western wetland boundaries, which SNR also marked for the survey crew to survey. SNR had also been conducting additional studies for Mr. Peter Townsend to obtain a better understanding of the hydrogeology in the area where the "wetland" is located and to study the storm water runoff issues in the general vicinity of the "wetland" area. The details of how these investigations were conducted, SNR's findings, conclusions, and recommendations are discussed in the body of this letter report. However, in summary, SNR has found that there is no naturally occurring wetland area present on the Townsend property. SNR has also found that there are no critical areas regulated streams located on the Townsend property. Because there are no regulated wetland areas or streams present on or in the vicinity of the subject property, there will be no need to conduct a wetland buffer restoration. Also, because there are no wetland or stream critical areas located on or near the subject property, there should be no critical areas restrictions that would hinder potential development activities on the Benjamin property or any of the Townsend properties. LO m CU a 29435 10TH AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report — Revision 1 SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 2.0 OVERVIEW As previously discussed, to obtain a better idea of the actual size of the area that has been listed as a wetland area by the City of Federal Way, SNR would be required to conduct a more detailed study of the soils on the property that would include the identification of the western boundaries of the 'wetland" area and the boundary stakes that SNR placed on the subject property would need to be surveyed by a licensed surveyor. To determine if the wetland has naturally occurring wetland hydrology, SNR would need to supplement their ongoing hydrogeologic and hydrologic studies that were being conducted to determine the influence of storm water on the drainage in this area. The additional studies that were conducted to supplement these previous studies, included studies to determine the source of the ground water that is responsible for creating the seeps and the small "stream" that has minor, discontinuous flow from the seep areas. SNR's original field studies conducted on March 27, 2007 did not include detailed wetland identification and delineation activities due to perceived time constraint by ECI, the firm that retained SNR's services. In lieu of performing a comprehensive wetland identification and delineation study, SNR was required to assume that the Category 3 wetland delineation established by the City of Federal Way was correct. Because SNR was required to assume a Category 3 wetland was present, SNR did not conduct detailed studies of 'wetland" hydrology or soils (to determine hydric soil boundaries). SNR did perform rough wetland size calculations based on the GPS data and observed, assumed wetland boundaries to the west. These calculations indicated that even allowing for a large margin of error, the wetland area would be too small to rate. However, as previously discussed, without accurate control points SNR could not determine the wetland size accurately enough to meet the regulatory requirements. 2.1. MARCH 27. 2007 WETLAND BOUNDARY AND BUFFER IDENTIFICATION The March 27, 2007 wetland boundary determination was based on the assumption that the "wetland" area was wetland that had been identified, delineated, and rated in accordance with the Washington State Wetland Identification and Delineation Manual, Publication #96-94, 1997. It also assumed that the wetland rating (Category 3) had be established in accordance with the Washington State Wetland Rating System for Western Washington - Revised, 2004, publication # 04-06-025, Washington Department of Ecology, Olympia, WA, as revised. co Because SNR was required to make these assumptions the boundary ca� determination was not based on detailed investigation and delineation. a 29435 LOTH AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report— Revision 1 O SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 Instead, the eastern wetland boundary stake locations were identified only by identifying the limits of hydrophytic vegetation, the presences of invasive upland vegetation, and the presence of saturated soils (no field tests were conducted for the presence of hydric soils). The buffer boundary stakes that were placed by SNR, were in lieu of having the wetland boundaries surveyed, therefore the buffer boundary stake locations were approximate (now that the wetland boundary stakes have been surveyed, the buffer boundary that has been determined by the surveyor, is now the actual wetland buffer boundary, presuming a wetland is present). The March 27, 2007 wetland boundary studies were only conducted on the east side of the "wetland" area because this was the only area of concern regarding the potential wetland restoration activities. Because only the eastern boundary had been identified, even if the "wetland" area were surveyed, it would not be possible to determine the wetland size because the western boundary had not been identified and staked. As previously discussed, in July 2007, Dr. Benjamin arranged to have the wetland boundary stakes surveyed. When Mr. Townsend discovered that the SNR boundary stakes were to be surveyed on the subject property, the two of you met to discuss the potential of having additional wetland studies conducted that would include the delineation of the western boundary of the "wetland area". 2.2 ADDITIONAL STUDIES Dr. Benjamin contacted SNR to ask if additional studies could possibly affect the location of the wetland boundary stakes. SNR advised Dr. Benjamin and Mr. Townsend that more detailed studies could affect the placing of the boundary stakes if SNR focused on the hydric characteristics of the soils. Additionally, the delineation of the western wetland boundary would allow SNR to calculate the wetland size after the boundary stakes had been surveyed. Also, by combining the information SNR had been gathering on the hydrology/hydrogeology of the "wetland area" and area in the vicinity of the wetland area with the other proposed activities SNR could also determine if there is naturally occurring wetland hydrology present and could determine the size of the wetland area. This information would allow SNR to determine if a naturally occurring, ratable wetland was present or not. Mr. Townsend has retained SNR to conduct (including ground water surface water investigations on and in the vicinity of the subject property) would provide a more accurate, scientific delineation of the "wetland" area, a 29435 10T" AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report — Revision 1 © SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 including the "wetland" size, "wetland" hydrology, and the nature of the "wetland" soils. SNR was given the authorization to proceed by Dr. Benjamin on July 16, 2007 with the goal of potentially relocating the wetland boundaries, Mr. Townsend also requested SNR to conduct additional field activities that included delineating the western wetland boundary which would provide the information necessary to determine the size of the "wetland area" and to use the hydrology and hydrogeology data and information SNR had previously obtained and would obtain to add to this report, by addressing the hydrology and hydrogeology of the wetland and surrounding area. SNR began field studies on July 18, 2007. These field studies included more detailed wetland boundary studies, focusing on the presence of hydric soil boundaries and to a lesser extent, the boundaries between hydrophytic vegetation and non-hydrophytic vegetation. These studies also included the identification of the "wetland" boundaries for the entire "wetland area". These boundaries were staked and identified with the appropriate flagging and information for a survey crew to locate and include in a detailed surveyed topographic map. CO m c� a 29435 10TH AVE SW, FEDERAL WAY - PARCEL #1196002267 Supplemental Letter Report- Revision 1 SNR Cornpany, Environmental Consultants LLC, 200t Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 3.0 WETLAND BOUNDARY SURVEY As previously discussed, the wetland boundary survey was conducted on July 18, 2007. This survey was conducted by a SNR Company senior -staff environmental geologist who is also a certified wetland professional. These studies were conducted under the supervision of a State of Washington Licensed Hydrogeologist and certified wetland professional. The soils were examined with an Oakfield Model C soil sampler and were examined for the presence of hydric soils using standard procedures proscribed in the Washington State Wetland Identification and Delineation Manual, Publication #96-94, 1997; any wetland rating, if feasible, would be conducted in accordance with the Washington State Wetland Rating System for Western Washington - Revised, 2004, publication # 04-06-025, Washington Department of Ecology, Olympia, WA, as revised. In addition to conducting the field studies (described in more detail below) to determine if the wetland boundary stakes could be relocated in eastern portion of the "wetland" area, SNR identified the western boundaries of the "wetland" area. SNR also incorporated previous hydrologic and hydrogeologic studies and surface water sampling to determine if natural wetland hydrology is responsible for the hydric soils and hydrophytic vegetation that is present in the "wetland area". To do this, the recharge source for the aquifer that responsible for the seep zones that have created that "wetland" environment were studied. These studies have been ongoing for several months and included surface water sampling of the ground water coming from the seep zone after the July 18, 2007 wetland studies were conducted. These activities were conducted to address three of SNR's primary concerns, 1) it was believed that the "wetland" area was too small to be rated, because there is no BAS currently available and accepted by Ecology to determine the potential habitat functional values for a wetland area that is less than 0.1 acres in size. 2) SNR believed that the hydrology for the "stream" and the wetland is not natural. SNR believed that this surface water was derived from nuisance water recharging a soil horizon that was not naturally a ground water aquifer and that the recharge of this soil horizon is not naturally derived exclusively from precipitation; and 3) the soils are not naturally hydric; SNR believed that the soils were influenced by manmade sources that in turn affected the soils, the growth of hydrophytic vegetation, and created a small "stream". The July 18, 2007 field activities included the identification of a western wetland boundary. This boundary and the readjusted eastern boundary were determined by establishing the boundary of hydric soils with non-hydric soils and to a lesser extent, the boundary of hydrophytic vegetation. W, c� a 29435 10T" AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report — Revision 1 0 SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 4.0 HYDROLOGY AND HYDROGEOLOGY The hydrogeologic and hydrologic studies that SNR had been conducting for Mr. Townsend included an investigation of the seep area. These studies have suggested that ground water that is responsible for the presence of the "wetland area" and the 'stream" is seeping from a soil horizon that should not be an aquifer. This is because the overlying soils have relatively low permeability (this has been confirmed in the field), so there would not typically be a significant recharge source from precipitation to create a potential aquifer where these surface soils are present. The seep area is at a low point with the area to the west having relatively significant slopes. The residences in this area used septic systems until approximately 1986. This is when the Lakehaven sewer system was installed and all of the residences in the immediate vicinity of the "wetland area" were disconnected from the septic systems and connected to the Lakehaven sanitary sewer system (one Lakehaven sewer line transects the incised relic channel in the northern portion of the `wetland" area). The residences in the immediate vicinity of the "wetland area" have been connected to the Lakehaven sanitary sewer for 20 years; there are no reported active septic systems in the immediate vicinity of the seep area. Based on communications with Mr. Townsend and his wife, prior to 1986 there were no seeps observed by them and there were no red alders present in the incised relic drainage channel. After 1987, the alders began growing, and it is assumed that the seeps caused the growth of the red alders and the hydrophytic vegetation. These seep areas are responsible for the proliferation of vegetation in southern portions of the relic channel areas. This prolific growth of red alders and other vegetation (including hydrophytic vegetation) can be attributed to the continual presence of water from the seep zone and relatively high nitrate levels in the water coming from the seep zone (see Attachment 3 - Laboratory Analyses of Seep Water). The following section discusses the field activities SNR has conducted. 4.1 FIELD ACTIVITIES SNR has conducted several different rounds of field activities on and in the vicinity of the subject property, with the wetland boundary readjustment survey and the survey of the western boundaries of the wetland area being conducted on July 18, 2007. Additional geotechnical and hydrogeologic field activities were also conducted on August 30th, 2007. These field activities included the excavation of test pits on the subject property and other properties owned by Mr. Townsend in the vicinity of the subject property. Additional field activities included the installation of four piezometers in four a 29435 JOT" AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report— Revisic. SNR Companv, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 of the test pits. The purpose of these piezometers is to obtain ground water data and to sample ground water quality. These field activities also included the collection of two surface water samples to be analyzed for the potential presence of e.coli and coliform bacteria and elements and ions that are scientifically accepted indicators for the presence of sanitary sewage in ground and surface water. 4.1.1 July 18, 2007 Field activities As discussed in the April 3, 2007 letter report, SNR Company was not requested to conduct a Wetland Identification and Delineation on the "wetland" area located on the subject property. SNR was to assume that the area was a Category 3 wetland per the Federal Way designation. However, this designation was not established by an in depth Wetland Identification and Delineation, it was established by a contractor who did a "drive by" evaluation of the area and recorded their findings on a one page delineation form. This delineation did mention the seep on the subject property, but no detailed field studies were conducted. When SNR conducted the field studies on the "wetland" area on March 27, 2007 it became obvious that the area was not a ratable wetland. It was also obvious that the hydrology was not natural and SNR believed that this hydrology was created by manmade sources. Therefore the hydrology for the "wetland area" that was created by these seeps was not natural wetland hydrology, which would make the "wetland" a non -wetland. The field activities that were conducted on July 18, 2007 were conducted to see if the wetland boundary stakes that were placed by SNR on March 27, 2007 could be adjusted by focusing more closely on the soils, by only placing the boundary stakes where the soils ceased to be hydric. Also, to determine the size of the wetland area, SNR included the delineation of the western boundary of the "wetland area". The wetland boundary determinations conducted during these field studies did include field testing of the soils to determine if they are hydric or not. The wetland boundaries previously established in the eastern portion of the wetland area were adjusted as necessary to the boundaries of where the soils were hydric or not (SNR allowed a buffer area of up to 10" between hydric and non-hydric soils). The boundaries of the western "wetland" area were determined using the same methodology that was used for the eastern area. Surprisingly, it was determined that most of the stakes that were placed during the initial study conducted on March 27, 2007 were placed appropriately, however, three stakes were located approximately two to three feet east of where the hydric soils were no longer present, these stake were replaced with new stakes. The new eastern wetland boundary and the newly a 29435 10TH AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report - Revision . OD SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 established western boundary would later be surveyed to establish accurate locations "wetland" boundaries which would allow SNR to calculate the size of the wetland area based on surveyed dimensions. The recently surveyed "wetland" boundary that includes SNR's size calculations is presented in Attachment 1 of this letter report. However, as discussed later in this letter report, the surveyors relied on the AutoCAD software used to draw the survey map to calculate the wetland area. SNR performed geometric and trigonometric calculations on the wetland area shown on the survey map and came up with an area that is very close to the area of the wetland SNR measured in the field (physically measuring the area with fiber glass tapes, rolling wheel measuring devices, and using submeter GPS coordinates). SNR's calculated area is smaller than the area obtained by the surveyors who used AutoCAD to calculate the dimensions, although even the surveyor's measurements indicate that the "wetland area" is too small to rate. The field activities conducted on July 18, 2007 established a complete "wetland" boundary based on the presence of hydric soils and to a lesser extent hydrophytic vegetation. However, to obtain more information on the ground water and geology in the "wetland area" and on the other Townsend properties SNR Company and Cornerstone Geotechnical Engineers conducted field activities at the subject property on August 30, 2007. 4.1.2 August 30, 2007 - Field Activities A backhoe was brought to the Townsend properties on August 30, 2007, at 7:30 AM; a SNR Company senior staff environmental geologist was present as were a geotechnical field technician and a SNR Company principal licensed hydrogeologist. SNR Company also brought four sets of well screen, risers, and "gravel pack" to install four piezometers on the Townsend properties, including one piezometer above the seep area. The backhoe was used to excavate several test pits on the Townsend properties, including the area above the seeps. The first test pit that was excavated was the one above the seep area; the field notes and a location map for these test pit excavations are included in Attachment 4 of this letter report. The only test pit observed to have ground water present was the test pit above the seep area. This ground water was found to be present approximately 4.5 feet below ground surface in a semi -confined aquifer that is present in a soil horizon that consists of fine to medium, relatively clean sand. N This aquifer is underlain by a clay horizon of unknown depth (because the a, backhoe could not excavate any deeper), however, observations of the "cliff" co 29435 10TH AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Lefler Reporl— Revision 1 SNR Company. Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 face to the north of the "plateau" area where the subject property is located suggest that this clay layer extends approximately six feet below the aquifer, The soils beneath this clay layer apparently include another ground water bearing zone because water is seeping from these soils. Based on SNR's observations of this cliff face, there are several ground water horizons in different semi -confined aquifers beneath the subject property. This ground water is most likely a contributing factor to the slope failures that can also be observed on this cliff face. The upper "aquifer" soils (the soils with the ground water that is responsible for the seeps in the "wetland area") are located beneath a clayey silt, with some fine sand. It is assumed that this surface soil has low to very low permeability and high porosity based on field observations at the time the test pit excavations were conducted. This is also based on field observations of these surface soils that were made by SNR Company's principal hydrogeologist. These observations indicate that during the late winter, when these soils were observed; they became nearly saturated due to a combination of precipitation and capillary fringe infiltration of subsurface ground water as the potentiometric pressure of the semi -confined ground water increased during the winter. It is evident that the soils in the aquifer that provides the water for the seep areas has relatively high interstitial pore pressure because when the backhoe encountered this soils, they "liquefied" and collapsed due to the release of the interstitial hydrostatic pressure when the confining soil horizon was removed. The aquifer soils had a strong odor of sewage, not the 'sulfur" odor of hydrogen sulfide gas that can be associated with reducing environments that can occur in wetland areas. This odor was very similar to the odor found at sewer treatment plants. As previously discussed, this is the only test pit where ground water was encountered. Two other test pits had wet soils starting at approximately 8 feet below ground surface, however, no ground water was observed. Piezometers were placed in two of the southern test pits and two of the northern test pits, including the test pit above the seep area. In addition to the excavation and logging of several test pits and the installation of four piezometers, SNR Company also collected a surface water sample from the seep area and from a storm water drainage channel bounding the southern portion of the paved access road to the Townsend property. This water sampling activity was conducted to determine if the sewage odor observed in the test pit above the seep area may be impacted with a leaking sewage system located to the south, southwest of the seep. CU 29435 10TH AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report -- Revision 1 SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 The water samples were collected in the afternoon of July 30, 2007 and were immediately transported to Spectra Laboratory in Tacoma, Washington, a State of Washington certified laboratory under standard Chain of Custody protocols. The samples were collected in general accordance with the State of Washington Department of Ecology standards for surface water sampling. The results of these analyses are discussed later in this letter report and the results of these analyses are presented in Attachment 3 of this letter report. aD rn CU a 29435 JOT" AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report— Revision 1 J SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 5.0 WETLAND ❑ESCRIPTtON The "wetland" area on the subject property is small and the hydrology is exclusively from the seep area at the southern terminus of a relic alluvial drainage channel that trends from the southwest to the northeast (a minor trend). Other hydrology comes from storm water that is being discharged into this drainage channel with most of this storm water coming from storm water collection drains from the surrounding access roads. However, most of the storm water discharges into this relic channel are to the north of the wetland area and the areas where this discharge is occurring in the relic channel do not support any hydrophytic vegetation nor are any other wetland characteristics observed. 5.1 Hydroiog4-7- and Water and Surface Water The seep area has some historically observed ephemeral characteristics, although it was producing surface water throughout the summer of 2007. It is anticipated that the majority of the recharge for the ground water that provides the water for the seep area is from Lakehaven's sanitary sewer lines that may be leaking. Another, potential, but unconfirmed source for the ground water recharge could be from surface and ground water that can infiltrate into the ditches the sanitary sewer lines are buried in. Most sewer lines are buried below ground in excavated ditches. These ditches are typically backfilled with gravel and then with the same soils that were excavated from these ditches. These soils are typically not compacted to the same density that the surrounding soils have. The combination of highly permeable gravels in the bottom of these ditches and less dense fill soils in these ditches can make these ditches ideal conduits for, potential sewer line leaks and surface and ground water that can find their way into these ditches. Because all sewer ditches, except where sewage must be pumped, have a downward gradient so they can flow towards the treatment plant(s) any sewer line leaks, infiltrated surface water and ground water that rises above the bottom of these ditches can be transported along these ditches to low points, whether these low points are siphon systems, pump stations, or the sewer treatment plant. If these ditches pass through areas where there are permeable soils and if water is flowing in these ditches, it can act as a ground water recharge source. The aquifer that is responsible for the seeps may also get recharge from upgradient buried infiltration trenches that receive roof, foundation, and retaining wall water discharges. These infiltration trenches would be located below the less permeable surface soils and would constitute artificial recharge Ln of a soil horizon that may not typically be an aquifer. CU a 29435 107H AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report — Revision 1 SNR Company, Environmental Consultants -LC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 SNR recognized that potential nuisance water may have created an aquifer that would not naturally exist and that the ground water in this aquifer was responsible for the seep zone in our April 3, 2007 report. This report also discussed that the seep and the red alders did not exist prior to the installation of sewer lines to the north and south of the seep area. During subsequent studies SNR also noted some unusual characteristics for the "ground water" being discharged from the seep area. This ground water includes significant amounts of iron reducing bacteria and free iron that occurs in a colloidal masses that are present in the "stream" surface water. The water in the "stream" was also cloudy in areas where the flow was very low and the water in the "stream" has an odor of sewage. This phenomenon is almost always associated with sewage line leaks or the presence of landfills upgradient of the seeps. However, there are no landfills upgradient of the seep area. Because there are no landfills or known active septic systems upgradient of the seep zone, but there are sanitary sewer lines located upgradient of the seep areas, SNR sampled the seep water for e.coli and coliform bacteria and for other elements and ions that would be identifiers of sewage in the ground water. SNR also sampled a storm water drainage ditch that is located south of the entry drive to the Townsend parcels because iron reducing bacteria and other evidence of potential impacts to the water in this ditch (this ditch can collect ground water also) were observed. During the winter, the seep area does flow slightly more than in the summer; however, the volume does not appear to increase significantly. The estimated stream flow is approximately 0.5 cubic feet per minute in the summer and estimated stream flow in the winter is 1 cubic foot per minute. When the only source of surface water in the relic drainage area is the seep area, the resulting "stream" does not flow very far before it either infiltrates or evaporates. However, the storm water that is drained to this relic channel from the drive areas can create enough flow and water volume to actually outfall to the Puget Sound beach located below the cliff areas. This flow is not a direct vertical flow down the cliff face to the north; this flow follows a winding path down the cliff face at relatively low velocities. Based on SNR's studies that have been conducted to date, the seep area will not typically generate enough flow to allow the "stream" to drain to the Puget Sound beaches below the cliff faces to the north (SNR has observed the flows since early March 2007). If the majority of the ground water that is providing the source water for the seep is from leaking sewer lines, this would be expected, because the soils that are located above the aquifer have relatively low permeability's, which means that recharge of the aquifer from precipitation would be minimal. Sanitary sewer flows are relatively stable, although they can increase with a 29435 10TH AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report— Revision 1 SNR Company. Environmental Consultants LLC. 2uui Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 rainfall and will increase as more connections are made. However, the seasonal fluctuations would be expected to be minimal if the system is designed correctly and does not collect storm water. This means that if there is increased flow of the seeps during the winter, this could potentially be attributed to the intentional infiltration of storm water from roof drains and other manmade recharge sources to the south and southwest of the seep area. However, it is unknown how much infiltration is occurring or how it will contribute to the seep flow during the months when this area gets its heaviest rainfall. It is anticipated that the piezometers SNR has installed will provide this information. As discussed in the April 3, 2007 report, it was suspected the seep flow was from nuisance water sources. It is now believed that the ground water flowing from these seeps is derived mostly from a leaking sanitary sewer system(s) (all of the local upgradient septic systems were supposed to have been abandoned 20 years ago, so it is assumed that these abandoned systems are not a potential source). SNR did consider that there may be active septic systems in the area, but could not find evidence of any in the immediate vicinity of the seep area. Personal communications with Peter Townsend (September 20, 2007) suggests that there are still some properties on 11th Avenue SW that have active septic systems, however, if the potentiometric surface of the ground water aquifers in this area is similar to the surface topography, then any ground water recharge from these active septic systems would be to the northwest of the study area, which means this ground water would not flow towards the seep area. Because all of the septic systems that are located to the south and southwest of the seep area are believed to have been decommissioned, the only other known potential source for the ground water recharge that contains e.coli and coliform bacteria as well as boron and nitrates is the Lakehaven sanitary sewer system. Since this recharge is from a nuisance water source and not a naturally occurring recharge source, this means that the seep is not naturally occurring and the water flow from the seep does not constitute a naturally flowing stream, in fact the water from the seeps would actually be considered a potential health hazard due to the presences of "living" pathogens in this water. This means that when future activities are conducted to stop this source of e.coli and coliform bacteria, these activities will most likely eliminate the seep area flow. r, (D n 29435 10T" AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report— Revision 1 z SNR Company, Environmental Consultants LLC, 20( Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 5.2 Soils There are hydric, saturated soils in the "wetland area"; however, the primary reason for these hydric soils is the artificial source of sewage that includes reducing bacteria and nutrients that will covert most silt and clay soils to hydric soils in a relatively short period of time (the natural process to create hydric soils takes much longer). The source of nitrates in the seep area would also encourage the growth of red alders and other vegetation, including hydrophytic vegetation in any area that is influenced by the seep waters. There is no evidence of any wetland areas forming where storm water is discharged into this natural relic channel; the only "wetland area" that is present is limited to where that active seeps are located. The soils in the "stream channel" formed by the seeps are underlain by a clay aquitard horizon. The ground water that is responsible for these seeps is "flowing" on this clay layer. This clay layer not only acts as an aquitard to the artificially recharged aquifer, it also presents a potential problem regarding the stability of any down gradient sloped areas, especially areas with very steep slopes such as the cliff faces to the north. This clay horizon extends to upper portion of the cliff face and the semi - confined aquifer above this clay layer drains on these slopes in the form of seeps. The ground water that is present above this clay surface can create conditions that are conducive to potential slope failure and may be responsible for the slope failures that have been observed on this cliff face that has almost a 100% slope angle. As discussed in the April 3, 2007 letter report, the near surface soils have been mapped by the United States Department of Agriculture, National Resource Conservations Service (NRCS) as Kitsap Silt Loam. This soil is believed to have been formed in a laucustrine environment. The soil profile on the cliff face includes several different soil horizons (Figure 2 - Photograph of Cliff Face), unconformities, crossbedding, and other features that would suggest a delta or near delta environment. It appears that there are sequences of less permeable and more permeable soils that are somewhat interlayered and that have created stratigraphy that includes aquifers and aquitards. Figure 3 - Ground Water on Cliff Face where Slope Failure has occurred, shows ground water flowing around a portion of the cliff face that has moved towards Puget Sound as does Figure 4. CO a) n3 29435 JOT" AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Lettei Rep- =vision 1 SNR Corrpanv, Enviionmental Consullants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 Figure 2- Photographs of Cliff Face 29435 10T" AVE SW, FEDERAL WAY - PARCEL #1196002267 Supplemental Letter Report- Revision © SNR Company, Environmental Consultants LLC, 2001 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 -JF4 .. : , 1.11. Figure 3 - Ground Water on Cliff Face where Slope Failure has occurred 29435 JOTH AVE SW, FEDERAL WAY - PARCEL #1196002267 0 a_ Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 Figure 4 — Slide Area on Cliff with Layered Stratigraphy 29435 10T" AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter RepoiI— Revision 1 J SNR Company, Environmental Consultants LLC. 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 29435 10T" AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Leber Report— Revision ? -J SiNR Companv Environmental Consultants LLC, z. Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 This type of stratigraphy has created the conditions where there are several partially -confined aquifers exposed on the cliff face. These aquifers are responsible for the several different (apparently, hydrologically isolated) seep zones observed to be present on the cliff face. The recharge sources for the isolated aquifers that are located below the upper most aquifer that also provides the water source for the seeps in the study area, is unknown. The geology of the soil horizons in the area of the "seeps" include the surficial soils that are believed to be fluvial deltaic in nature; that are associated with glacial advances and retreats. This area was most likely a glacial lake located reasonably close to a delta fringe or was in the actual delta/floodplain complex when glacially influenced rivers discharged into a historic glacial lake. The surface soils on the subject property exhibit the characteristics that would be seen in sediments that are discharged on a delta fringe into a laucustrine environment. However, the deeper sediments exhibit the characteristics of soils that are in an active delta discharging into a water body, with the cycles of fine sediments and then coarser sediments, including gravels and presence of crossbedding, unconformities, and other features typically associated with active fluvial -deltaic deposition. The cyclic nature of this deposition is associated with different flow rates of the rivers discharging into this laucustrine (or similar water body) environment. The estimated dip of these soils is to the north, northwest at approximately 20% towards the north in the vicinity of the subject property (it is suspected that the subject property is located on a structural anticline, so the dip of these soils can change to steeper angles as you get closer to the anticline axis). The general regional topography of the where the study area is located is concave, bowl like, topography (conforming to the topography of a near shore laucustrine environment) that also dips to the north, northwest. 5.3 GEOMORPHOLOGY As previously discussed, the subject property has the geomorphology of a near shore laucustrine or near shore marine environment that was actively receiving sediments from a fluvial -deltaic source. These soils are layered with sequences of fine soils above and below sequences of coarser soils. The soils that are comprised mostly of fines, act as potential aquitards, the coarser soils act as potential ground water aquifers. However, if the ground water aquifers receive enough recharge to create interstitial hydrostatic pressure due to semi -confined or confined hydrogeologic conditions that are N significant to "lift" the soils in the aquifer off of the aquitards' fine soils; the coefficient of friction can drop significantly, potentially causing these soils 29435 10TH AVE SW, FEDERAL WAY - PARCEL #1196002267 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 above the aquitard to have "ground movement" if the slope angle of these soils is at or above critical angels and if these soils are not confined by other soils (in this case any direction to the north). The elevated hydrostatic pressure and the drop in the coefficient of friction can cause the soils above the aquitard to detach from the aquitard and the resulting ground movement would be in the direction of the slope angle (towards Puget Sound). This has apparently happened approximately 264 feet east of the Benjamin property where a relatively significant transverse landslide relic is located. This landslide has the typical "cusped" shape with a well defined head scarp and a well defined down dropped slide block (Figure 5 - Topographic Map Showing Relic Landslide Area). ,019 FIEZOMETER FROM A NG COUNTY twr Figure 5 - Topographic Map Showing Relic Landslide Area ffim �! _ SLIDE fiLO't a� —17iN,jti+H11 PRQPE.CT'f��'� ��' �I HEAD _l-Vr JL 1, �. A " The incised drainage channel areas observed throughout the area where the subject property is located are believed to be relic floodplain channels that were formed as the current plateau was uplifted by the Cascadia subduction zone and the water levels dropped globally in the last 10,000 years due to the formation of the ice sheets in the extreme northern and southern hemispheres of the planet (sea level has changed several times in the past, the current levels are at least 100 meters lower than the highest sea levels that have been observed in the Holocene fossil record). The "wetland area" does not exhibit the typical wetland morphological characteristics, of either a depressional or stream fringe wetland, with most of the wetland being present on sloped areas where the soils are saturated €2 29435 10TH AVE 5W, FEDERAL WAY — PARCEL 91196002267 Supnlemen�al �e!�er Rapoll -Revision I SINIF, Company Enviroornenhl Consultants i,LC. 7_. Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 due to ground water aquifer being exposed in this area. The ground water in this aquifer is from known artificial sources; most likely the Lakehaven sanitary sewer system, with the possibility of some recharge coming from the intentional infiltration of storm water to the south and southwest. Additionally, the 'wetland area" is too small to rate even if the hydrology and hydric soils were from natural sources. The survey map shows an area of 2,981 square feet based on the CAD program calculated "wetland area"; however based on SNR's geometric and trigonometric calculations, the wetland area is actually, 2,203 square feet in area. The habitats for wetland areas this small have not been studied adequately enough to be able to rate the habitat functions. This has been acknowledged by Ecology in a 2004 determination that any wetland that is less than a tenth (0.1) of an acre in size cannot be rated using the best available science provided in the Washington State Wetland Rating System for Western Washington - Revised, 2004, publication # 04-06-025, Washington Department of Ecology, Olympia, WA, as revised to determine whether to perform a rating. 5.4 HYDROGEDEGGY Based on the field studies that have been conducted on the site, including the excavation of test pits, the installation of piezometers, and the analyses of the ground water coming from the seep areas; SNR has determined that the ground water aquifer that is providing the water for the seep zones is being influenced by nuisance water sources that are coming from manmade sources, including sanitary sewer systems. There is also the likelihood that if storm water infiltration is being conducted upgradient from the seep area, that the ground water could also be recharged from these artificial recharge points. Base on SNR's observations of the cliff face to the north of the subject property, the stratigraphy is that of cyclic deposition of soils ranging from fine soil horizons such as silts and clays to horizons of sands with some silt in sequential layers. Some of the horizons with more sands have ground water present in and can be observed as seeps on the cliff face. Each of these ground water bearing soil horizons (aquifers) is underlain and overlain by less permeable soils. The near surface ground water aquifer that is responsible for the seeps in the "wetland" area has no significant, discernable source for recharge from local precipitation, the flow in these seep areas does not significantly rise during the winter months, especially if potential infiltration of storm water is occurring and is factored in. a 29436 10TH AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report — Revision (D SNR Company, Environmental ConSLlltants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 The ground water that is creating the seeps has bacteria present that are indicative of sewage and the element boron and the ion nitrate are not found in naturally occurring ground water (but are in sewage). Therefore, SNR must conclude that the primary source of the seep water is from a sanitary sewer system, which is not a natural source, which means the hydrology of the wetland is also not natural and the "stream" associated with the seep is also not natural. All of the evidence suggests that the seep water is from nuisance water being introduced into the subsurface soils by human activities. co N 0) CD CU a 29435 10TH AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report— Revision 1 SNR Company: Environmental Consultants LLC, 200r Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 6.0 FINDINGS The following are SNR's findings related to the "wetland" area and the "potential" stream area. 6.1 WETLAND AREA Based on the additional field activities and research conducted by SNR if the wetland area were naturally occurring, it would be too small to rate. SNR has calculated the area to be 2,203 square feet, which is much smaller than the 4,356 square feet required by Ecology before a wetland area can be rated. Additionally, the hydrology that supports the hydrophytic vegetation is from human created sources, it does not exhibit the characteristics of natural wetland hydrology. The hydric soils are the result of the soils that have been exposed to water that contains high levels of reducing and potentially pathogenic bacteria, with two strains identified by Strata Laboratory as e.coli and coliform bacteria. There is evidence that a reducing environment has formed within the aquifer to the south, the evidence for this is the presence of iron reducing bacteria and "slime" that is present in the ground water flowing from the seeps. This is further substantiated by the test pit that was excavated to the south of the seep area which had a strong sewage odor. The soils that were excavated beneath the surface soils have ground water present in them and were under relatively high hydrostatic pressure that created relatively high interstitial pore pressure. When this pressure was released, the aquifer soils collapse on themselves and become a slurry of sandy soils and water. These soils have a strong sewage odor and the clays beneath these soils are being subjected to a reducing environment that is apparent on the clay surfaces observed in the test pits. The "wetland area" would be too small to rate if it were a natural wetland, the hydrology is not a naturally occurring wetland hydrology, and the soils have been artificially influenced to create hydric conditions. 6.2 "STREAM" The hydrology that is present in the seeps is artificial, the incised alluvial channel is a relic from when this area was a floodplain, and therefore is not an active stream channel. There are no natural head waters for any stream flow in this relic channel and the seep flow alone is not known to extend to the waters of the State or Waters of the United States. It anticipated that the only time there is flow in this relic channel is when there are significant discharges from the storm water discharge pipes that have been placed in this relic drainage channel. The flow from the seep area is not natural and is a CD actually from a source that will need to be eliminated as a source of ground a 29435 10TH AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report — Revision t O SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 water because the seep water is impacted with pathogenic bacteria that can cause illnesses in humans if ingested. 7.0 CONCLUSIONS After conducting several field studies, research, and obtaining laboratory analyses of the water flowing from the seep areas, SNR has concluded that the hydrology of the "wetland area" is from artificial sources and that the a significant amount of the ground water (if not all of it) that is seeping into the "wetland area" and that supports the hydrophytic vegetation and also supports the growth of the red alders, and creates a small "stream" has pathogenic bacteria present as well as elements and ions that are not naturally occurring in ground water, including boron and nitrates. The primary element and ion that are present are not found in naturally occurring ground water, but are typically indicative of sewage that is coming from a sanitary sewer system. Therefore, the wetland area lacks the hydrology necessary to be delineated as a wetland and the size of the wetland area is too small to rate even if it were a naturally occurring wetland area. The "stream" that is present in the wetland area has a head water from ground water that is not naturally occurring and is derived from sources that are manmade. Water bodies that are derived from manmade sources are not considered to be natural critical areas streams, and in this case the stream is impacted by a sewage leak source that will need to be remedied. When the sewage leak is repaired, this source water will no longer be present. The only other water that is discharged into the relic channel is storm water that has been diverted from private drive areas to the east. Due to the very low amount of traffic, these discharges would not typically require an NPDES permit and the source of this water would not constitute a natural stream headwater source, so there is no natural stream present in the relic channel area. 29435 JOT" AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Lettei Report— Revision 1 `; SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 8.0 RECOMMENDATIONS, Based on SNR's findings and conclusions, there is no naturally occurring or ratable wetland located on the subject property nor is there any natural stream located on the subject property that could be characterized using best available science because the source water is nuisance water, believed to be mostly derived from a leaking sanitary sewer system. The City of Federal Way should remove the wetland ranking on the subject property and should not classify a minor stream to be present on or in the vicinity of the subject property. The City should proceed with the approval of the Benjamin soldier pile wall and should not require any wetland restoration activities or other wetland related restrictions. Sincerely, of W SNR COMPANY, ENVIRONMENTAL CONSULTANTS LLC 0� f r, nglrreerlrsp Geotag[st 347 Steven F. Neugebauer - LG, LHG, LEG, REA, QWS President Steven F. Ne ge ue Attachments: Survey Maps Including one with corrected wetland area Calculations Site Photographs Laboratory Analyses of Water from Seep Zone Field Notes from July 181h and August 30, 2007 29435 10TH AVE SW, FEDERAL WAY - PARCEL #1196002267 Supplemental Letter Report— Revision SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 ATTACHMENT 1 - SITE SURVEY MAP WITH CACULATED WETLAND AREA 0 CM N to a 29435 10TH AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report- Revision 1 © SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 �Yw 2.94t� St I I I 1 I y � L � SW 296th �t 29435 10T" AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report — Revision 1 0 SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 Topographic Plan with Piezometers err :t 12;h AVE SW 1 1� i��, A � �Ilt' �t��3siiiC��•eAlir:E; l�9 i A Portion of the Southwest Ouarter of the Northwest Quarter of Section 6. Township 21 Nwih. Range 4 Enat. W.M. fAND SUR✓C1'lNL TopographicalSurveyRAR,VARLi I-M :z4 ; cY A SSOC'. /NC. _ � ' CO M il 29435 10TH AVE SW, FEDERAL WAY - PARCEL #1196002267 Supplemental Letter Report- Revision 1 SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 ATTACHMENT 2 - SITE PHOTOGRAPHS co M cc d 29435 10TH AVE SW, FEDERAL WAY - PARCEL #1196002267 Supplemental Letter Report - Revision ', © SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 Test Pit above the 29435 10TH AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report— Revision SNR Company, Environmental Consultants LLC, 2007 Area N M a_ Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 Storm Water Ditch to Left (South) Test Pit Showing Layered Stratigraphy 29435 10T" AVE SW, FEDERAL WAY - PARCEL #1196002267 Supplemental Letter Report— Revision 1 SNR Company, Environmental Consultants LLC, 2uur Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 5Li ys Strom Water Ditch Samole Location NOR 4A: ■r 1 Repositioned Wetland Boundary Stake 29435 10T" AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report- Revismi 1 SNR Compan,, Environmental Corisultanls LLC 2007 _5 - 1�: �, r-. -- � r,. ,. -`� _ =:i .. f ,� ti ♦ �.. ��- � _ - _:�� ':.t:. C �� .. �' i_ f. -,yam' .. , �y. �J. 1] }�. , "fit ,�. - - . J•w �v Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 e of Soils in "Wetland Area" CO M () 0) M a_ 29435 10T" AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report - Revision i © SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 ATTACHMENT 3 — LABORATORY ANALYSES OF SEEP ZONE WATER rn ch a� c� C. 29435 10T" AVE SW, FEDERAL WAY - PARCEL 01196002267 Supplemental Letter Report - Revision 1 © SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 SPECTRA Laboratories 2221 Ro.t N'a) • T.Ittana, \VA 98421 • (253) 272-48511 • faa ('_53157_' 483x aww opocua-lah eom 09112l2007 Project: Tmvsend Property SNR Co. Sample Matrix: Water 15211 3rd PI NE Date Sampled: 08/30,, 2007 Duvall, WA 98019 Date Received: 08/30/2007 Attn: Steve Neugebauer Spectra Project: 2007080461 Client 11) Spectra N Analyte Result Units Method 05-07-007-S1 I Boron 0.11 me L EIIA 200.7 05-07-007-S1 I Orthophosphate, ac P < 0.01 Ing-1 SM4500-1' C OS-07407-SI I Nitrate 0.9 Ine 1: N SM4500N031) t15-07-007-S1 I Colifenn Bacteria Present SM9223 05-07-007-S1 1 t=. Colt Bacteria Present SK19223 05-07-007-S2 _ Boron 0.18 Ing 1. 1PA200' 05-07-007-S2 _ Orthophosphate. as 1' -- 0 01 Ing'L SN14500-P C' 05-07-007-S2 _ Nitrate 0.7 mg 1: N SM4500N031) 05-07-007-S2 2 C'otiform Bacteria Present SM9223 05-07-007-S2 2 E. Coli Bacteria N—in S:,19223 SPECTRA LABORATORIES r S -c ykihK5. Laboratory Manager .' 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J 29435 10TH AVE SW, FEDERAL WAY - PARCEL #1196002267 Supplemental Letter Report- Revision 1 0 SNR Company, Environmental Consultants LLC. 2007 I I < o o G nN re y s1 � — A3 I — m E h 4t 1 �a E�A 2 e � L i•0 � l rn W J a F Q W .W N 0 a N 2 Q CAI W� J a s < N S J ; M Ui a W ¢ N 01 C1 Q) M IL Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 ATTACHMENT 4 - FIELD NOTES FROM SNR FIELD ACTIVITIES N N cm M a 29435 10Tx AVE SW, FEDERAL WAY - PARCEL #1196002267 Supplemental Letter Report- Revision 1 © SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 SNR Company FIELD REPORT Environmental, Ecological, Hydrology, and Engineering Geology 15211 3rd Place NE n Duvall, WA 98019 ■ 425-788-3015 www.snrcompany.com Project Name: Townsend/Benjamin Project Number: 05-07-007 On July 18, 2007, a SNR Company senior staff environmental geologist and certified wetland professional was on -site at the Townsend Property to re -survey the wetland boundary to the east and conduct a new wetland boundary survey to the west. SNR Company conducted the second wetland boundary identification and characterization activities using hydric soil field indicators, and to some extent hydrophytic vegetation, in the eastern area to determine if the initial wetland boundary stakes could be repositioned with more detailed studies of the soils. These procedures were also used to determine the western wetland boundary. A total of 13 points were examined and established, which includes 5 points from established by on March 27, 2007. The newly established wetland boundaries were marked with a flagged surveyor's stake and were labeled with the date, company name, and boundary point number. The soil investigation activities included the collection and inspection of subsurface soil samples under the supervision of a licensed hydrogeologist (to 18" below ground surface — BGS) using an Oakfield Model C soil sampler. Vegetation types were determined in the field by a qualified wetland professional using A Field Guide to the Common Wetland Plants of Western Washington & Northwestern Oregon, Seattle Audubon Society Trailside Series, 1997 as one of the primary references'. Each flagged stake was also located with a sub -meter GPS (Magellan Mobile Mapper Pro) and the distances between the stakes were measured with a 300 foot fiber glass surveyor's tape, a rolling wheel measuring device, and steel tapes. SNR had also placed buffer boundary stakes at the approximate distances from the wetland boundary stakes (25 feet). After conducting the second round of sampling, if a wetland boundary marker was readjusted the corresponding wetland buffer boundary stake was adjusted accordingly. A map was generated showing the locations, and the distances between them, of the sampling points. Also included on the map were distances between each point. t co Samples were collected and photos taken of plant species that could not be identified in the field. These samples, photos, and habitat information were then compared to the US Department of Agriculture Database for wetland plants and other plant identification resources. Plants that were believed to be potentially invasive were or noxious weeds compared to the plants listed on Washington State Noxious Weed Control t1 Board's and the US Army Corps of Engineers' websites. 29435 10T" AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report -- Revision �1 SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 The wetland boundaries were established by identifying the change in the soils from hydric to non-hydric. Where the change was gradual or otherwise not clear, SNR added at least 10 inches to the potential extent (increase in area) of the area where the soils appeared to be non-hydric. SNR also used the presence of hydrophytic vegetation to assist with the delineation in areas where the hydric/non-hydric soil boundaries were not easily discernable. The map that was prepared in the field and the GPS coordinates were provided to the surveyors to allow them to identify the stakes and confirm the names on the stakes matched the locations on SNR's field map (w [iiSurc 'Lille aianca had not been I IIUVCU). 2�14t4 51 , 2 w ;W 296,h `;t a� M a 29435 10TH AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemen[al Letter report— Revision r SNR Co[npany. Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 srva com�,a,,, FIELD REPORT Environmental, Ecological, Hydrology, and Engineering Geology 15211 31d Place NE ■ Duvall, WA 98019 ■ 425-788-3015 www.snrcompany.com Project Name: Townsend/Benjamin Project Number: 05-07-007 On August 30, 2007 an SNR Company senior staff environmental geologist was on -site at the Townsend Property to install four (4) piezometers in four of six test excavations being completed by Cornerstone Engineering. Cornerstone Engineering had subcontracted with Northwest Trucking and Excavating to excavate six (6) test pits in order to document the subsurface geology. Originally in discussions between the client(s) and SNR, it was recommended that three (3) piezometers be installed to monitor groundwater elevations and possible groundwater contamination in the area. Later the client(s) requested that SNR place a • fourth piezometer at the site for additional monitoring. SNR Company installed two (2) piezometers in the eastern section of the subject property (designated P-1 and P-3) and two (2) piezometers (designated P-2 and P-4) to the western portion of the subject property. The piezometers are constructed of 2-inch, schedule 40 PVC pipes with flush threaded ends risers with a screened section at the bottom. The screens used in P-1, P-2, and P-3, are custom cut at .028 and the fourth (P- 4) is a standard .020 cut. TEST PIT 1 Test Pit TP-1 was placed in the eastern section of the subject property and is above the seep. A 4-inch layer of topsoil is composed of a fine to medium grained, sub -angular sand with some organics. The layer is dark yellowish brown to yellowish brown and was moist. The topsoil is underlain by interbeded layers of fine to medium grained, subangular, sandy silt with clayey lenses. This material is yellowish brown to olive brown with some iron oxide staining. The unit was moist and between 24 and 48 inches thick and contained debris. A layer of fine to medium grained, sub -angular to sub - rounded sands with cobble lenses is beneath the sandy silt. The layer is approximately 24 to 28 inches thick and is olive brown in color. This soil unit was saturated and caving extensively. This unit is most likely a confined aquifer in the area. Beneath the aquifer layer is another unit of fine to medium grained, subangular, sandy silt with clayey lenses. This material is M yellowish brown with medium moisture and is between 24 and 48 inches a) thick. ti 29435 10TH AVE SW, FEDERAL WAY - PARCEL #1196002267 Supplemental Letter Report- Revision 1 ID SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 The piezometer P-1 was constructed of a 5-foot riser with a .028 custom cut screen and around the screen, SNR placed 10/20 filter sand. Due to the saturation of the soils, the same 10/20 filter sand was used to the ground surface. The original depth for the piezometer was to be 10 feet below ground surface but SNR was unable to maintain the planned depth due to the caving encountered. Therefore the final depth of the piezometer is approximately 6 feet below ground surface (BGS). The PVC pipe was labeled with the piezometer number, the screen size, company name, and date. The equipment was sprayed bright orange for visibility. The PVC pipe was notched and future surveying and groundwater levels will be measured from that point. TEST PIT 4 Test Pit TP-4 was placed in the western section of the subject property. A 3- inch layer of topsoil is composed of a fine to medium grained, sub -angular sand with some organics. The layer is dark yellowish brown to yellowish brown and was moist. The topsoil is underlain by interbeded layers of fine to medium grained, subangular, sandy silt with clayey lenses. This material is yellowish brown to olive brown with medium moisture and is between 24- and 36-inches thick. A layer of fine to medium grained, sub -angular to sub - rounded sands with cobble lenses is beneath the sandy silt. The layer is approximately 24-inches thick and is olive brown in color. Beneath this unit is another unit of fine to medium grained, subangular, sandy silt with clayey lenses. This material is yellowish brown with medium moisture and is between 48- and 60-inches thick. Organics were found in the test pit at 12 below the ground surface. The piezometer P-2 was constructed of a 5-foot riser with a .020 standard cut screen and around the screen, SNR placed 10/20 filter sand. The remaining space around the piezometer was backfilled with the native material. The piezometer was placed 10 feet below ground. After the piezometer was placed, the PVC pipe was labeled with the piezometer number, the screen size, company name, and date. The equipment was sprayed bright orange for visibility. The PVC pipe was notched and future surveying and groundwater levels will be measured from that point. TEST PIT 5 Test Pit TP-5 was placed in the western section of the subject property. A 4- inch layer of topsoil is composed of a fine to medium grained, sub -angular sand with organics. The layer is dark yellowish brown and was moist. The topsoil is underlain by interbeded layers of fine to medium grained, subangular, sandy silt with clayey lenses. This material is yellowish brown with medium moisture and is approximately 36-inches thick. A layer of fine to medium grained, sub -angular to sub -rounded sands with cobble lenses is a 29435 LOTH AVE SW, FEDERAL WAY — PARCEL 01196002267 Supplemental Letter Report— Revision 1 SNR Company, Environmental Consultants LLC, YUU/ Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 beneath the sandy silt. The layer is approximately 24-inches thick and is olive brown in color. Beneath this unit is another unit of fine to medium grained, subangular, sandy silt with clayey lenses. This material is yellowish brown to olive brown with medium moisture and is between 48- and 60- inches thick. The piezometer P-4 was constructed with two (2) 5-foot riser sections and a .028 custom cut screen. Around the screen, SNR placed 10/20 filter sand and backfilled the remaining space around the piezometer with the native material. The piezometer was placed 10 feet below ground. After the piezometer was placed, the pipe was labeled with the piezometer number, the screen size, company name, and date. A 5-foot section of PVC pipe remains above ground at the time the piezometer was placed until the fill material had time to settle below the joint. At a later point in time, the second section of PVC pipe will be removed and caped. The lower PVC section will be notched and future surveying and groundwater levels will be measured from that point. TEST PIT 6 Test Pit TP-5 was placed in the eastern section of the subject property. A 6- inch layer of topsoil is composed of a fine to medium grained, sub -angular sand with organics. The layer is dark yellowish brown to yellowish brown and was moist. The topsoil is underlain by interbeded layers of fine to medium grained, subangular, sandy silt to silty sand with clayey lenses. This material is yellowish brown with medium moisture and is approximately 36- to 40- inches thick. A layer of fine to medium grained, sub -angular to sub -rounded sands with cobble lenses is beneath the sandy silt. The layer is approximately 24-inches thick and is olive brown in color. Beneath this unit is another unit of fine to medium grained, subangular, sandy silt with clayey lenses. This material is yellowish brown to olive brown with medium moisture and is between 48- and 60-inches thick. The piezometer P-3 was constructed with a 5-foot riser sections and a .028 custom cut screen. Around the screen, SNR placed 10/20 filter sand and backfilled the remaining space around the piezometer with the native material. The piezometer was placed 10 feet below ground. After the piezometer was placed, the pipe was labeled with the piezometer number, the screen size, company name, and date. The equipment was sprayed bright orange for visibility. The PVC pipe was notched and future surveying and groundwater levels will be measured from that point. WATER SAMPLING The SNR Company senior -staff field geologist who has current 40 hour (TO HAZWOPER training conducted the water sampling activities after the a 29435 10T" AVE SW, FEDERAL WAY — PARCEL #1196002267 Supplemental Letter Report— Revision 1 SNR Company, Environmental Consultants LLC, 2007 Supplemental Report to the Benjamin Wetland Restoration Plan September 27, 2007 placement of the piezometers. Standard sampling protocol called for the collection of two (2) sets of samples using clean, sterile containers that had been picked up from the laboratory. The samples collected for bacterial testing were placed in bottles containing a preservative while the other samples did not require preservatives. The samples were collected, labeled and placed into a delivery container. The samples were delivered to Spectra Analytical under standard chain of custody. The samples were analyzed for boron, nitrates, phosphates, and bacteria. The first sample S-1 was collected from the culvert running along the southeast side of the private road leading to the Townsend home. The water had grease -like platelets floating on the surface and a rust colored substance floating in it. The second sample S-2 was collected from a channel in the wetlands area. The sample had the same rust colored substance floating in it. CO a� rn M a 29435 LOTH AVE SW, FEDERAL WAY - PARCEL #1196002267 Supplemental Letter Report - Revision 1 ) SNR Company, Environmental Consultants LLG, �uui 'r UNCONTROLLED STORMWATER RU NOF OVER BLUFF IS CAUSING EROSION OWNER OF PARCEL N0, 062 104-907 1 1 _ HAS PART IALLY B LO CKE O C HANN EL WICONC- RUBBLE8, OTHER DEBRIS P I R E,'UES?EU COAWN EL C❑NVeYA NCL NI PROVEN INTO, i AA Ti:,. nR LN AW TO BD use llf "i f�. 2�7 Iu y�7 d 5 AP PR0X.WE7L.AND lSEWAGE OUTFALLLOCA71 CHANNEL HAS BEEN TIGHTLINED ] �, ^•" >• -L W/8" CORRUGATED PIPE 1' :• � fir- R �!•e OWNERS � � � • RAM 0N SAN C HEZ, LINDA LO ERA 29411 12TH AVE SW 253-041-5885 ++ 4 e•r r if 7 �. FA xr1s REQUESTED INCREASE IN HT, OF EX IST'No !`► ASPHALT BERM &EXPANSION OF ROROW AY TO PROVIDE FOR TURNAROUND y�1`1f I f' irk _•'a� l ' [ i7 yJ SUBJECT OWNEP: PETER TOWNSEND •,r.rt 1:!v4�3 '�':4 29508 12TH AVE. SW '•.' _ 'fi (SW 295TH HAS BEEN VACATED) 640 i46S . � 1i3fiiiEVafi[lu .�J• :. r � r � S- ,29STH-ST r 29508 12th Ave. SW Peter Townsend, 253-839-2947 LEGEND Shoreline Management Plan CONSERVANCY NATURAL RURAL URBAN Wetlands Landslide Hazard Erosion Hazard Parcels Map Printed -May 28, 2009 Map prepared by: N City of Federal Way Public Works, SWM Division 253-835-2700 100 0 100 Feet Note: This map is intended for use as a graphical representation only. The City of Federal Way makes no warranty as to its accuracy.