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Home My WebLink AboutRS_Techinical Information Report_191107_v1.pdf Civil Engineers ● Structural Engineers ● Landscape Architects ● Community Planners ● Land Surveyors Preliminary Technical Information Report PREPARED FOR: Sunset Highlands Mixed Use, LLC 15007 Woodinville-Redmond Road, #A Woodinville, WA 98072 PROJECT: Sunset Highlands Mixed Use Renton, WA 2190210.10 PREPARED BY: Ryan Inouye, EIT Project Engineer REVIEWED BY: Scott T. Kaul, PE, LEED AP Project Manager J. Matthew Weber, PE Principal DATE: November 2019 Preliminary Technical Information Report PREPARED FOR: Sunset Highlands Mixed Use, LLC 15007 Woodinville-Redmond Road, #A Woodinville, WA 98072 PROJECT: Sunset Highlands Mixed Use Renton, WA 2190210.10 PREPARED BY: Ryan Inouye, EIT Project Engineer REVIEWED BY: Scott T. Kaul, PE, LEED AP Project Manager J. Matthew Weber, PE Principal DATE: November 2019 I hereby state that this Technical Information Report for Sunset Highlands Mixed Use has been prepared by me or under my supervision, and meets the standard of care and expertise that is usual and customary in this community for professional engineers. I understand that City of Renton does not and will not assume liability for the sufficiency, suitability, or performance of drainage facilities prepared by me. 11/08/2019 Preliminary Technical Information Report Sunset Highlands Mixed Use 2190210.10 Table of Contents Section Page 1.0 Project Overview ............................................................................................................................ 1 1.1 Purpose and Scope............................................................................................................. 1 1.2 Predeveloped Conditions .................................................................................................... 1 1.3 Development Conditions ..................................................................................................... 2 2.0 Conditions and Requirements Summary .................................................................................... 2 2.1 Core Requirements ............................................................................................................. 2 2.1.1 C.R. #1 – Discharge at the Natural Location ......................................................... 2 2.1.2 C.R. #2 – Off-Site Analysis .................................................................................... 2 2.1.3 C.R. #3 – Flow Control Facilities ............................................................................ 3 2.1.4 C.R. #4 – Conveyance System .............................................................................. 3 2.1.5 C.R. #5 – Construction Stormwater Pollution Prevention ...................................... 3 2.1.6 C.R. #6 – Maintenance and Operations ................................................................ 3 2.1.7 C.R. #7 – Financial Guarantees and Liability ........................................................ 3 2.1.8 C.R. #8 – Water Quality Facilities .......................................................................... 3 2.1.9 C.R. #9 – On-Site BMPS ....................................................................................... 3 2.2 Special Requirements ......................................................................................................... 5 2.2.1 S.R. #1 – Critical Drainage Areas .......................................................................... 5 2.2.2 S.R. #2 – Flood Hazard Area Delineation .............................................................. 5 2.2.3 S.R. #3 – Flood Protection Facilities ...................................................................... 5 2.2.4 S.R. #4 – Source Controls ..................................................................................... 6 2.2.5 S.R. #5 – Oil Control .............................................................................................. 6 2.2.6 S.R. #6 – Aquifer Protection Area .......................................................................... 6 3.0 Off-Site Analysis ............................................................................................................................ 6 3.1 Downstream Analysis.......................................................................................................... 6 3.2 Upstream Analysis .............................................................................................................. 6 4.0 Flow Control, Low Impact Development (LID), and Water Quality Facility Analysis and Design ............................................................................................................................................. 6 4.1 Existing Site Hydrology ....................................................................................................... 7 4.2 Developed Site Hydrology .................................................................................................. 7 4.3 Performance Standards ...................................................................................................... 7 4.4 Flow Control System ........................................................................................................... 8 Preliminary Technical Information Report Sunset Highlands Mixed Use 2190210.10 4.5 Water Quality System ......................................................................................................... 8 5.0 Conveyance System Analysis and Design .................................................................................. 8 6.0 Special Reports and Studies ........................................................................................................ 8 7.0 Other Permits ................................................................................................................................. 8 8.0 Construction Stormwater Pollution Prevention Analysis and Design ..................................... 8 8.1 ESC Plan Analysis and Design ........................................................................................... 8 8.2 SWPPS Plan Design ........................................................................................................... 8 9.0 Bond Quantities, Facility Summaries, and Declaration of Covenant ....................................... 9 10.0 Operation and Maintenance Manual ............................................................................................ 9 11.0 Conclusion ...................................................................................................................................... 9 Preliminary Technical Information Report Sunset Highlands Mixed Use 2190210.10 Appendices Appendix A Figures A-1 ............. Vicinity Map A-2 ............. Soils Map A-3 ............. Existing Conditions Map A-4 ............. Developed Conditions Map A-5 ............. Downstream Dra6inage Map A-6 ............. FEMA Flood Map A-7 ............. Aquifer Protection Map Appendix B Not Used Appendix C Hydrologic Analysis C-1............. Drainage Basin Map C-2............. Preliminary WWHM Report Appendix D Geotechnical Engineering Report Appendix E Non-Structural BMPs A-1 ............. Required Best Management Practices (BMPs) for all Properties with Commercial Activities A-8 ............. Storage or Solid and Food Wastes (Including Cooking Grease) A-45 ........... Maintenance of Public and Private Utility Corridors and Facilities Appendix F Critical Areas Report By Sewall Wetland Consulting, Inc., dated March 22, 2018 Note: this report is preliminary and as such has an outdated site plan with similar encroachments and surfacing proposed Preliminary Technical Information Report Sunset Highlands Mixed Use 1 2190210.10 1.0 Project Overview 1.1 Purpose and Scope This report accompanies the SEPA application for the Sunset Highlands Mixed Use Project. The project site is located in the City of Renton in the southwest quarter of Section 3, Township 23 North, Range 5 East, Willamette Meridian in the City of Renton, King County, Washington. This site is located at 4409 Northeast Sunset Boulevard (see Appendix A, Figure A-1 for Vicinity Map). The Sunset Highlands Mixed Use project is located on Parcel 0223059090 totaling approximately 0.82 acres with the proposed disturbed area totaling approximately 0.75 acres. The proposed project is for a new mixed use commercial and residential building of approximately 8,100 square feet. An asphalt drive/fire lane is proposed around the building with parking areas at the north end. The project also includes stormwater improvements, water, sanitary sewer, and dry utilities. The design for this project meets or exceeds the requirements of the 2017 City of Renton Surface Water Design Manual (Storm Manual), which establishes the methodology and design criteria used for this project. 1.2 Predeveloped Conditions South Sound Geotechnical Consulting evaluated the existing soils (see Appendix D). The onsite soils were evaluated to be approximately 1 foot of topsoil, followed by sand to approximately 2.5 to 3.5 feet. The geotechnical engineer determined “Bioswales, pervious pavements, or other shallow dispersion systems could be considered in the upper sand soils, if allowed by the City.” The remainder of the site is glacial till to the maximum explored depths by the geotechnical engineer. The glacial till, referred to as hardpan, is considered poor soil for infiltration. The geotechnical engineer has determined the hardpan below the upper sand is considered impermeable to vertical groundwater flow. Existing Vegetation/Cover: The existing site has been cleared in the past , and there are only a few significant trees located around the perimeter of the site. There are several trees located adjacent to the western property line. The site consists primarily of light brush and grasses , and three driveways accessing the site from north end. An existing sanitary 8-inch sewer main runs along the western portion of the project site with an existing manhole located near the southwest corner of the parcel. There is an existing 12-inch water main north of the site on the north side of Sunset Boulevard. Power and other utilities are located adjacent to the project site. There are several existing driveways at the north end of the site. The remainder of the site remains undeveloped. The site slopes to the south from the road at approximately 3 percent. The site sheet flows stormwater to the existing stream at the south end of the site. See Appendix A, Figure A-5 for the Downstream Drainage Map beyond the property boundaries. An evaluation of wetlands, streams, and buffers was conducted by Sewall Wetland Consulting (see Appendix F). The stream is the upper ditched portion of the Honey Dew Creek, determined as a Type 4, non-fish bearing stream. The stream has a 50-foot degraded and denuded natural buffer. Preliminary Technical Information Report Sunset Highlands Mixed Use 2 2190210.10 1.3 Development Conditions Approximately 0.75 acres of the 0.82 acres plot will be disturbed. A 21-inch fir tree and 24-inch fir tree along the western property line will be removed to accommodate utilities. The proposed improvements are for a new mixed use building, an asphalt drive/fire lane, and parking. The project also includes stormwater improvements, water, sanitary sewer , and dry utilities. The existing stream will be provided with a 40-foot stream buffer that will be enhanced with this project. Stream buffer improvements will aid in stabilizing the area next to the stream; a full stream buffer enhancement plan will be provided by Sewall Wetland Consulting under separate permit. A stormwater detention system with an outfall control structure, permeable paving, and bio- retention cells are proposed to mitigate the impact of the new development. 2.0 Conditions and Requirements Summary 2.1 Core Requirements 2.1.1 C.R. #1 – Discharge at the Natural Location Currently, runoff from the project site flows south to Honey Creek , which flows through the southeast corner of the site and continues west. This flow regime is mimicked by the proposed storm discharge to Honey Creek. 2.1.2 C.R. #2 – Off-Site Analysis AHBL staff performed a Level 1 off-site drainage analysis in May of 2018. The analysis included:  Defining and mapping the study area;  Reviewing available information on the study area;  Field inspecting the study area; and  Analyzing the existing drainage system , including its existing and predicted problems, if any. The project discharges to Honey Creek where it crosses the southeast corner of the project site. The stream continues to flow to the west through a 71-inch by 47-inch elliptical culvert. The streambed just west of the culvert is heavily overgrown with blackberry vines and other brush. The stream flows behind neighbor’s outbuilding/shop. The property was marked with “No Trespassing” signs. Once it passes the building, it immediately flows into two, 36- inch by 60-inch arched pipe culverts. From this point it flows underground across the neighboring lot and then across NE Sunset Boulevard to the north where exits the two arched pipes. From this point, the runoff flows into a ditch line then rounds the corner and flows north along the east side of Union Avenue. Once it has turned this corner, it flows a short distance approximately 30 feet to two more arched pipes, and it continues to flow to the west across Union Avenue. Once across Union Avenue, the creek exits the culverts and flows into a gravelly streambed that borders the backside of the lots Preliminary Technical Information Report Sunset Highlands Mixed Use 3 2190210.10 that front Sunset Boulevard. This streambed drops in elevation considerably and flows between a number of apartment complexes, and eventually flows into the Honey Creek Open Space. This is a treed park -like area approximately ¾-mile downstream from the subject property. The stream is at the bottom of a very deep canyon at this point. To our knowledge, there are no existing downstream restrictions; and the project will maintain the discharge to pre-developed rates. Therefore, the downstream conveyance system should have adequate capacity to convey the proposed flows from this project. A floodplain analysis was evaluated to determine the maximum water surface elevation anticipated for Honey Creek (see Section 2.2.2 below). 2.1.3 C.R. #3 – Flow Control Facilities Per the Storm Manual, the project requires Flow Control Duration Standard – Matching Forested Conditions. An underground stormwater detention system is proposed to meet flow control requirements. Proposed mitigation will meet the predeveloped conditions as evaluated using the WWHM program from 50 percent of the 2-year up to the full 50-year flow and matching peaks for the 2- and 10-year return periods. 2.1.4 C.R. #4 – Conveyance System The project includes the construction of a new conveyance system to direct discharge to Honey Creek. Closed-pipe conveyance is provided from the detention system to the discharge to Honey Creek. Roof drains discharge directly to the storm detention system. Conveyance calculations will be provided with the final site development plans. 2.1.5 C.R. #5 – Construction Stormwater Pollution Prevention An erosion and sediment control plan will be included with the site development submittal package. A Construction Stormwater Pollution Prevention Plan will be included with the site development submittal package. 2.1.6 C.R. #6 – Maintenance and Operations A maintenance plan for the stormwater management system will be provided with the site development permit. 2.1.7 C.R. #7 – Financial Guarantees and Liability A bond, assignment of funds, or certified check will be provided as required pri or to construction. 2.1.8 C.R. #8 – Water Quality Facilities Bioretention cells provide water quality treatment for areas subject to pollution generating surfaces. Detailed discussion of the water quality system is provided in Section 4.1. 2.1.9 C.R. #9 – On-Site BMPS The project falls in the Large Lot BMP requirements based on the size of the property. Core requirement #9 BMPs have been evaluated in the order described per the Storm Manual with infeasibility justification provided. Preliminary Technical Information Report Sunset Highlands Mixed Use 4 2190210.10 1. Full Dispersion Infeasibility Justification: Full dispersion requires that 100’ minimum vegetated flow path be provided. The small area and site plan do not allow for the required flow path. Full dispersion also requires a maximum 15% of the site be impervious surfaces. The project will convert approximately 76% of the site to impervious surfaces. 2. Full Infiltration of Roof Runoff Infeasibility Justification: Full infiltration of Roof Runoff has been determined infeasible by the geotechnical analysis performed by South Sound Geotechnical Consulting. The geotechnical analysis recommends not using trenches or ponds. 3. Option 1 - Full Infiltration Infeasibility Justification: Full infiltration has been determined infeasible by the geotechnical analysis performed by South Sound Geotechnical Consulting. The soil layer that can infiltrate is shallow. The proposed detention system will require excavation below this layer; therefore, infiltration in the upper soil was determined infeasible. The detention system proposed will have exposed subgrade to promote infiltration (to the maximum extent possible). 3. Option 2 - Limited Infiltration Infeasibility Justification: Limited infiltration BMPs per the Storm Manual are the same as full infiltration systems but located in poor infiltrative soils that are likely to clog and work less effectively over time. Infiltration has been determined infeasible by the geotechnical analysis performed by South Sound Geotechnical Consulting. Shallow facilities are recommended by the geotechnical engineer. Limited infiltration facilities would not adequately provide infiltration. 3. Option 3- Bioretention Bioretention is proposed for the site to meet the On-Site BMP and water quality requirements. The bioretention facility is proposed in the upper alluvium soils where small amounts of infiltration are feasible. The shallow bioretention cell and amended soil mix is proposed to stay 3’ from the hardpan soils. The amended soils should help to protect and preserve the infiltrative soil layer. All of the pollution generating impervious surfaces will be directed to the bioretention cells. 3. Option 3- Permeable Pavement Permeable paving is proposed for the site to meet the On-Site BMP and water quality requirements. Permeable paving is proposed at the north end of the site in front of the building and as a portion of the parking area in the northeast corner. The geotechnical analysis has determined soils in the area meet the suitability criteria. Soil Amendment: All disturbed areas will be amended per the soil amendment BMP. The pollution generating impervious surfaces will be provided with treatment and flow control. Preliminary Technical Information Report Sunset Highlands Mixed Use 5 2190210.10 2.2 Special Requirements 2.2.1 S.R. #1 – Critical Drainage Areas The project does not lie within a critical drainage area. 1. Master Drainage Plans (MDPs) The project does not lie within an area covered by an approved Master Drainage Plan. 2. Basin Plans (BPs) The project does not lie within an area with an adopted Basin Plan. 3. Salmon Conservation Plans (SCPs) The project does not lie within an area with an adopted Salmon Conservation Plan. 4. Lake Management Plans The project does not lie within an area with an adopted Lake Management Plan. 5. Hazard Mitigation Plan The project does not lie within a flood hazard area and is not tributary to any identified flooding per the City of Renton Hazard Mitigation Plan, April 2010. 6. Shared Facility Drainage Plans (SFDPs) The project does not propose a Shared Facility Drainage Plan. 2.2.2 S.R. #2 – Flood Hazard Area Delineation The proposed project is not within or adjacent to a flood hazard area as identified by the City of Renton in the Hazard Plan per FEMA study. A Minor Floodplain Analysis for Honey Creek at the discharge will be provided with final site development permit. Preliminary delineation has determined the 100-year water surface to be 2.94 feet above the bottom of the stream. The upstream maximum floodplain elevation has been delineated at 392.05. To determine the potential flooding elevation the downstream culvert was evaluated and a preliminary backwater analysis conducted. The upstream culverts have a maximum combined discharge capacity of 25.2 cfs based on the slope and material using Manning’s Equation. The combined 100-year flow from the site and upstream drainage will be effectively conveyed through the downstream elliptical culvert. The downstream culvert has a capacity of 43.77 cfs. A preliminary backwater analysis has been utilized to evaluate the ultimate creek level adjacent to the project based on a 100-year storm flow of 25.7 cfs. The backwater analysis can expect the water level to reach approximately 2.94 feet at about 150 feet from the culvert. The anticipated water surface will be 392.05. The discharge for the site is set at 392.75, to be above the anticipated maximum water level. 2.2.3 S.R. #3 – Flood Protection Facilities The project does not meet the any of the conditions requiring flood protection facilities. Preliminary Technical Information Report Sunset Highlands Mixed Use 6 2190210.10 2.2.4 S.R. #4 – Source Controls Source control BMPs as identified in the King County Stormwater Pollution Prevention Manual and Renton Municipal Code, Title IV, have been incorporated into the layout and design of the proposed stormwater management system. The site use will require non-structural BMPs to maintain source control. BMPs A-01, A-08, and A-45 from the King County Stormwater Pollution Prevention Manual shall be adhered to. 2.2.5 S.R. #5 – Oil Control The proposed site is not expected to meet the high-use site criteria. No oil control is proposed. 2.2.6 S.R. #6 – Aquifer Protection Area The project site is within Zone 2 of Aquifer Protection Area (APA). An Enhanced Basic Water Quality Treatment system will treat the pollution generating surfaces onsite. Adverse impacts to the aquifer are not anticipated. Per geotechnical findings , the onsite soil infiltration rate is less than 9 inches per hour; therefore, no lining is proposed. 3.0 Off-Site Analysis 3.1 Downstream Analysis See Core Requirement #2 above for AHBL Downstream analysis of the site. 3.2 Upstream Analysis The project site does not receive any substantive runoff from offsite properties except for the flows through Honey Creek, which flows through the southeast corner of the project site. The current flow pattern will not be modified by this project. 4.0 Flow Control, Low Impact Development (LID), and Water Quality Facility Analysis and Design An underground detention system and control structure is proposed to meet flow control requirements. Bioretention and permeable paving is proposed to meet LID requirements. The bioretention cells will provide water quality treatment. Preliminary design is based on Appendix C-1 Basin Map and Basin characteristics below. The Water Quality Basin is characterized as follows: Total Area: 0.48 acres Building Area: 0.00 acres Asphalt Pavement Area: 0.30 acres Sidewalk Area: 0.02 acres Landscape Area: 0.16 acres The remaining area in the Detention Basin is characterized as follows: Total Area: 0.26 acres Building Area: 0.19 acres Preliminary Technical Information Report Sunset Highlands Mixed Use 7 2190210.10 Asphalt Pavement Area: 0.00 acres Permeable Paving Area: 0.07 acres Sidewalk and Patio Area: 0.00 acres Landscape Area: 0.00 acres 4.1 Existing Site Hydrology The existing site has been previously cleared. Although previously cleared, to meet the area - specific flow control facility requirements the existing conditions will be modeled as forest. The threshold discharge area currently directs site runoff to Honey Creek, a stable stream showing no impacts of high flows and no known drainage problems. The existing basin for modeling is determined as the same footprint as the developed conditions to provide stormwater management replicating existing conditions. The geotechnical analysis identifies the potential for some infiltration at the upper layer of alluvium. To best mimic the observed site conditions the predeveloped hydrology will be evaluated as type C soils. 4.2 Developed Site Hydrology All onsite improvements will be provided with flow control and water quality management. A bioretention facility will provide water quality management for pollution generating surfaces. A storm- chamber detention system will provide flow control to match predevelopment and post- development flow duration curves for all flows from 50 percent of the 2-year flow up to the full 50-year flow. All onsite impervious surfaces will be conveyed to the detention system to effectively mitigate runoff. The Geotechnical Engineering Study discovered dense till soils ranging from 3.5 to 4.5 feet below existing ground surface. Therefore, the soils should be modeled as Type C soils. 4.3 Performance Standards The Area-Specific Flow Control Facility requirement for this project will be the Flow Control Duration Standard – Matching Forested Conditions. The City has identified the required flow control standards per the City of Renton Flow Control Application Map. This project falls under the Large Lot BMP Requirements. Permeable paving and bioretention cells are proposed to meet on-site BMP requirements. Stormwater from the site will discharge close to Honey Creek to reduce the impact on site soils and soil stabilization. To meet conveyance requirements, all new pipe systems will be sized to sufficiently convey and contain the 25-year peak flow. Enhanced Basic Water Quality Treatment is required for pollution generating target surfaces. The pollution generating surfaces will be conveyed to a bioretention cell for treatment before entering the detention system. A commercial site development permit is required; therefore, source control BMPs are required. Structural source controls will be provided based on the use of the site as commercial retail and housing. Nonstructural source control measures will be provided per special requirement #4. See Appendix E for Non-Structural BMPs. The site is not considered high-use; therefore, oil control is not required. Preliminary Technical Information Report Sunset Highlands Mixed Use 8 2190210.10 4.4 Flow Control System The flow control system schematic layout can be found on the civil plan sheets. See Appendix C-3 for supporting documentation on the preliminary sizing of the detention system and flow control structure. Per Storm Manual Table 1.2.9.A on-site BMP credits will be applied to determine flow control requirements. The on-site BMP credit for bioretention will model tributary impervious surfaces as 90% impervious and 10% grass. The on-site BMP credit for permeable pavement (unlined with no underdrain) will model permeable pavement area as 50% impervious and 50% grass. 4.5 Water Quality System To treat runoff from pollution generating surfaces bioretention cells are proposed. Soils under the permeable pavement meet the soil suitability criteria. The bioretention cell has been sized to meet the 91% infiltration rate (see Appendix C-3 for the WWHM printout). The bottom of the bioretention soil will be placed to maintain a 3’ separation from the poor soils onsite where hardpan may be encountered. 5.0 Conveyance System Analysis and Design Closed-pipe conveyance is provided from the detention system to the discharge at Honey Creek. Roof drains are conveyed to the detention system. A conveyance analysis will be provided with final site development plans. 6.0 Special Reports and Studies A Minor Floodplain Analysis will be provided with final site development plans. A geotechnical engineering report has been prepared by South Sound Geotechnical Consulting (see Appendix D). A Critical Areas Report has been prepared by Sewall Wetland Consulting, Inc. (see Appendix F). 7.0 Other Permits This project will require a Building Permit and Civil Construction Per mit. A Buffer Enhancement plan will be required for the existing stream buffer. 8.0 Construction Stormwater Pollution Prevention Analysis and Design 8.1 ESC Plan Analysis and Design A Construction Stormwater Pollution Prevention Plan will be provided for final site development plans. 8.2 SWPPS Plan Design A Temporary Erosion and Sediment Control Plan (TESC Plan) will be provided for the final site development plans. A CSWPP supervisor will be appointed by the Contractor at the time of construction to implement and update TESC plans as required. The CSWPP supervisor shall be a Certified Professional in Erosion and Sediment Control or a Certified Erosion and Sediment Control Lead. The CSWPP supervisor will be responsible for compliance with all City of Renton construction stormwater requirements. Preliminary Technical Information Report Sunset Highlands Mixed Use 9 2190210.10 9.0 Bond Quantities, Facility Summaries, and Declaration of Covenant A bond quantities worksheet will be provided for final site development permit. All easement requests will be submitted to the City of Renton Community and Economic Development (CED) Department. 10.0 Operation and Maintenance Manual An operation and maintenance manual will be provided for final site development. 11.0 Conclusion This project is designed to meet the 2016 City of Renton Surface Water Design Manual guidelines for stormwater management. This analysis is based on data and records either supplied to or obtained by AHBL, Inc. These documents are referenced within the text of the analysis. The analysis has been prepared utilizing procedures and practices within the standard accepted practices of the industry. We conclude that this project, as proposed, will not create any new problems within the existing downstream drainage system. AHBL, Inc. Ryan Inouye, EIT Project Engineer RI/STK November 2019 Q:\2019\2190210\10_CIV\NON_CAD\REPORTS\Prelim Storm\20191009 Rpt (Storm TIR) 2190210.10.docx Preliminary Technical Information Report Sunset Highlands Mixed Use 2190210.10 Appendix A Figures A-1 .................... Vicinity Map A-2 .................... Soils Map A-3 .................... Existing Conditions Map A-4 .................... Developed Conditions Map A-5 .................... Downstream Dra6inage Map A-6 .................... FEMA Flood Map A-7 .................... Aquifer Protection Map 2215 North 30th Street Suite 300 Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX SUNSET HIGHLANDS MIXED USE 2190210.10 VICINITY MAP A-1 NOT TO SCALE VICINITY MAP Soil Map—King County Area, Washington Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 1/10/2018 Page 1 of 35261480526149052615005261510526152052615305261540526155052615605261570526158052614805261490526150052615105261520526153052615405261550526156052615705261580563190563200563210563220563230563240563250563260 563190 563200 563210 563220 563230 563240 563250 563260 47° 30' 16'' N 122° 9' 39'' W47° 30' 16'' N122° 9' 35'' W47° 30' 13'' N 122° 9' 39'' W47° 30' 13'' N 122° 9' 35'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 10N WGS84 0 25 50 100 150 Feet 0 5 10 20 30 Meters Map Scale: 1:517 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: King County Area, Washington Survey Area Data: Version 13, Sep 7, 2017 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jul 8, 2014—Jul 15, 2014 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Soil Map—King County Area, Washington Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 1/10/2018 Page 2 of 3 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI AgC Alderwood gravelly sandy loam, 8 to 15 percent slopes 0.0 4.5% RdC Ragnar-Indianola association, sloping 1.0 95.5% Totals for Area of Interest 1.0 100.0% Soil Map—King County Area, Washington Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 1/10/2018 Page 3 of 3 2215 North 30th Street Suite 300 Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX SUNSET HIGHLANDS MIXED USE 2190210.10 EXISTING CONDITIONS MAP A-3 UP UP UP NE SUNSET BLVDSTORM CHAMBERDETENTION SYSTEMPERVIOUSCONCRETE40'BUFFERBIORETENTIONW 14"FIR 16"FIR 24"FIR 12"FIR 20"FIR 16"FIR 30"FIR 16"FIR CATCH BASINRIM 400.1312" CONC SW 397.30 IE177.5 LF SANITARY SEWER MANHOLE RIM 396.32 8" PVC S 393.35 IE 8" PVC SE 393.38 IE 8" PVC N 393.27 IE 303.5 LF WF A3 WF A5 WF A7 WF A8 WF AA8 WF AA6 WF AA5 WF AA2 WF AA1 ROCK E R Y ROCK E R Y ROCKERY - - - --5' HOG WIRE FENCE6' CY C L O N E F E N C E LSPVLSLSLS WF AA7 WF AA4 WF AA1 M ----WATER VALVE WATER MANHOLEASPHALT---------------- - - - - - - - ----- - -------------- - - - ASPHALT ASPHALTASPHALTASPHALTGRAVELASPHALT-SIDEWALK 48" P o pl a r 24" CEDAR 30" Fir 18" MAPLE 30" FIR WF A 1 WF A2 WF A6 WF AA3 CATCH BASIN12" CONC NE 394.86 IE12" CONC N 394.84 IE12" CONC SW 394.91 IE SANITARY SEWERMANHOLERIM 400.4312" CONC NE 388.08 IE8" PVC S 388.91 IE12" CONC SW 388.08 IECATCH BASINRIM 399.9312" CONC NE 395.33 IE12" CONC SW 395.21 IESANITARY SEWER12" CONC NE 386.00 IE 12" CONC SW 385.95 IE SANITARY SEWERMANHOLERIM 400.7112" CONC NE 388.80IE12" CONC SW 388.61IE >SB SIGNAL BOX SBTV EXISTI N G S T R E A M N63°57'27"E 1423.14' (M)1423.21' (ST)595.07' (C)595.10' (ST)S26°02'33"E 45.00' 48" CMP CULVERT 389.11 IE 8" CONCRETE CULVERT 393.56 IE 48" CMP CULVERT 388.89 IE 20' SEWER EASEMENTBIORETENTIONPERVIOUSASPHALTCONTROLSTRUCTURENGRAPHIC SCALE030601" = 30 FEET15Civil EngineersStructural EngineersLandscape ArchitectsCommunity PlannersLand SurveyorsNeighborsSUNSET HIGHLANDS MIXED USE2190210.10Q:\2019\2190210\10_CIV\CAD\EXHIBITS\Developed Conditions.dwgDISCHARGE TOHONEY CREEK 2215 North 30th Street Suite 300 Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX SUNSET HIGHLANDS MIXED USE 2190210.10 DOWNSTREAM DRAINAGE MAP A-5 2215 North 30th Street Suite 300 Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX SUNSET HIGHLANDS MIXED USE 2190210.10 FEMA FLOOD MAP A-6 2215 North 30th Street Suite 300 Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX !!! ! ! !!!!! ! ! !! ! ! !! ! !! PW-12 PW-11PW-17 PW-4 PW-9 PW-8 RW-3 RW-2 EW-3 PW-5A PW-12 PW-10 ,§-405 ,§-405 115544tthhPPllSSEESW 34th StSW 34th St East Valley RdEast Valley Rd114488tthhAAvveeSSEE140th Ave SE140th Ave SE164th Ave SE164th Ave SETalbot Rd STalbot Rd SN 30th StN 30th St 68th Ave S68th Ave SRai n i e r A v e S Rai n i e r A v e S SE 192nd StSE 192nd St SE May V a l l e y R d SE May V a l l e y R d E Valley HwyE Valley HwySE P e t r o v i t s k y R d SE P e t r o v i t s k y R d Forest D r S E Forest D r S E S 128th StS 128th St 112th Ave SE112th Ave SE84th Ave S84th Ave SSE 168th StSE 168th St S 55th StS 55th St N 10th StN 10th St NE 2nd StNE 2nd St SW 41st StSW 41st St 116th Ave SE116th Ave SE140th Ave SE140th Ave SESE 192nd StSE 192nd St 148th Ave SE148th Ave SE114400tthhAAvvee SS EE SW 27th StSW 27th St Benson Rd SBenson Rd SHouser Way NHouser Way NLind Ave SWLind Ave SWN 8th StN 8th St PP uu gg ee ttDDrrSSEERReennttoonnAAvv ee SS SW 7th StSW 7th St I-405 FWYI-405 FWYRainier Ave NRainier Ave NNNEEPPaa rrkk DDrr NE 4th StNE 4th St SW 43rd StSW 43rd St SE Carr RdSE Carr Rd NE 3rd StNE 3rd StLogan Ave NLogan Ave NDuvall Ave NEDuvall Ave NEI-405 FWYI-405 FWYI-405 FWYI-405 FWYI-405 FW YI-405 FW Y I-405 FWYI-405 FWYNE 4th StNE 4th StI-405 FWYI-405 FWYII--440055FFWWYYI-405 FWYI-405 FWYI-405 FWYI-405 FWY I-405 FWYI-405 FWYI-405 FWYI-405 FWY NE 4th StNE 4th St BN IncBN IncBN IncBN Inc BN IncBN Inc BN IncBN IncBN I n c BN I n c BN IncBN IncBN I n c BN I n c BN IncBN Inc BB NN IInnccBN I n c BN I n c BN IncBN IncBN In cBN In c BN IncBN IncCedar River Green River Black River May Creek Duwamish Waterway Springbrook Creek Lake Washington Lake Youngs Panther Lake Lake Boren Reference 15-B Wellfield Capture Zones One Year Capture Zone Five Year Capture Zone Ten Year Capture Zone Cedar Valley Sole SourceAquifer Project Review Area Streamflow Source Area Cedar Valley Sole Source Aquifer Aquifer Protection Area Zones Zone 1 Zone 1 Modified Zone 2 Network Structure !Production Well !Springbrook Springs Renton City Limits Potential Annexation Area Groundwater Protection Areas Date: 01/09/2014 µ0 1 2Miles PROJECT SITE SUNSET HIGHLANDS MIXED USE 2190210.10 AQUIFER PROTECTION MAP A-7 Preliminary Technical Information Report Sunset Highlands Mixed Use 2190210.10 Appendix B Not Used Preliminary Technical Information Report Sunset Highlands Mixed Use 2190210.10 Appendix C Hydrologic Analysis C-1.................... Drainage Basin Map C-2.................... Preliminary WWHM Report UP UP UP NE SUNSET BLVDSTORM CHAMBERDETENTION SYSTEMPERVIOUSCONCRETE40'BUFFERBIORETENTIONW 14"FIR 16"FIR 24"FIR 12"FIR 20"FIR 16"FIR 30"FIR 16"FIR CATCH BASINRIM 400.1312" CONC SW 397.30 IE177.5 LF SANITARY SEWER MANHOLE RIM 396.32 8" PVC S 393.35 IE 8" PVC SE 393.38 IE 8" PVC N 393.27 IE 303.5 LF WF A3 WF A5 WF A7 WF A8 WF AA8 WF AA6 WF AA5 WF AA2 WF AA1 ROCK E R Y ROCK E R Y ROCKERY - - - --5' HOG WIRE FENCE6' CY C L O N E F E N C E LSPVLSLSLS WF AA7 WF AA4 WF AA1 M ----WATER VALVE WATER MANHOLEASPHALT---------------- - - - - - - - ----- - -------------- - - - ASPHALT ASPHALTASPHALTASPHALTGRAVELASPHALT-SIDEWALK 48" P o pl a r 24" CEDAR 30" Fir 18" MAPLE 30" FIR WF A 1 WF A2 WF A6 WF AA3 CATCH BASIN12" CONC NE 394.86 IE12" CONC N 394.84 IE12" CONC SW 394.91 IE SANITARY SEWERMANHOLERIM 400.4312" CONC NE 388.08 IE8" PVC S 388.91 IE12" CONC SW 388.08 IECATCH BASINRIM 399.9312" CONC NE 395.33 IE12" CONC SW 395.21 IESANITARY SEWER12" CONC NE 386.00 IE 12" CONC SW 385.95 IE SANITARY SEWERMANHOLERIM 400.7112" CONC NE 388.80IE12" CONC SW 388.61IE >SB SIGNAL BOX SBTV EXISTI N G S T R E A M N63°57'27"E 1423.14' (M)1423.21' (ST)595.07' (C)595.10' (ST)S26°02'33"E 45.00' 48" CMP CULVERT 389.11 IE 8" CONCRETE CULVERT 393.56 IE 48" CMP CULVERT 388.89 IE 20' SEWER EASEMENTBIORETENTIONBASINLIMITSWQ SUBBASINLIMITSNGRAPHIC SCALE030601" = 30 FEET15Civil EngineersStructural EngineersLandscape ArchitectsCommunity PlannersLand SurveyorsNeighborsSUNSET HIGHLANDS MIXED USE2190210.10Q:\2019\2190210\10_CIV\CAD\EXHIBITS\Developed Basin Map.dwgPROPOSED BASIN AREASAREAROAD0.30 ACRESROOF0.19 ACRESPERMEABLE PAVING*0.07 ACRESSIDEWALK0.02 ACRESLAWN0.16 ACRESTOTAL0.75 ACRES* PERMEABLE PAVING MODELING CREDIT IS 50%LAWN AND 50% ROADSTORMWATERREQUIREDPROVIDEDDETENTION0.218 AC-FT(9,504 CF)0.218 AC-FT(9,506 CF)BIORETENTION1,056 SF1,180 SFWATERQUALITYSUBBASINWATERQUALITYSUBBASIN WWHM2012 PROJECT REPORT Sunset Highlands Mixed Use 11/8/2019 1:21:34 PM Page 2 General Model Information Project Name:Sunset Highlands Mixed Use Site Name:Sunset Highlands Mixed Use Site Address: City: Report Date:11/8/2019 Gage:Seatac Data Start:1948/10/01 Data End:2009/09/30 Timestep:15 Minute Precip Scale:1.167 Version Date:2018/03/08 Version:4.2.14 POC Thresholds Low Flow Threshold for POC1:50 Percent of the 2 Year High Flow Threshold for POC1:50 Year Sunset Highlands Mixed Use 11/8/2019 1:21:34 PM Page 3 Landuse Basin Data Predeveloped Land Use Predeveloped Basin Bypass:No GroundWater:No Pervious Land Use acre C, Forest, Flat 0.7 Pervious Total 0.7 Impervious Land Use acre Impervious Total 0 Basin Total 0.7 Element Flows To: Surface Interflow Groundwater Sunset Highlands Mixed Use 11/8/2019 1:21:34 PM Page 4 Mitigated Land Use Roof and Pervious Pave Bypass:No GroundWater:No Pervious Land Use acre C, Lawn, Flat 0.04 Pervious Total 0.04 Impervious Land Use acre ROADS FLAT 0.03 ROOF TOPS FLAT 0.19 Impervious Total 0.22 Basin Total 0.26 Element Flows To: Surface Interflow Groundwater Detention Vault Detention Vault Sunset Highlands Mixed Use 11/8/2019 1:21:34 PM Page 5 Water Quality Bypass:No GroundWater:No Pervious Land Use acre C, Lawn, Flat 0.16 Pervious Total 0.16 Impervious Land Use acre ROADS FLAT 0.3 SIDEWALKS FLAT 0.02 Impervious Total 0.32 Basin Total 0.48 Element Flows To: Surface Interflow Groundwater Surface `Surface ` Sunset Highlands Mixed Use 11/8/2019 1:21:34 PM Page 6 Routing Elements Predeveloped Routing Sunset Highlands Mixed Use 11/8/2019 1:21:34 PM Page 7 Mitigated Routing Detention Vault Width:33 ft. Length:111 ft. Depth:4 ft. Discharge Structure Riser Height:3 ft. Riser Diameter:18 in. Notch Type:Rectangular Notch Width:0.011 ft. Notch Height:1.350 ft. Orifice 1 Diameter:0.64034 in.Elevation:0 ft. Element Flows To: Outlet 1 Outlet 2 Vault Hydraulic Table Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)Infilt(cfs) 0.0000 0.084 0.000 0.000 0.000 0.0444 0.084 0.003 0.002 0.000 0.0889 0.084 0.007 0.003 0.000 0.1333 0.084 0.011 0.004 0.000 0.1778 0.084 0.014 0.004 0.000 0.2222 0.084 0.018 0.005 0.000 0.2667 0.084 0.022 0.005 0.000 0.3111 0.084 0.026 0.006 0.000 0.3556 0.084 0.029 0.006 0.000 0.4000 0.084 0.033 0.007 0.000 0.4444 0.084 0.037 0.007 0.000 0.4889 0.084 0.041 0.007 0.000 0.5333 0.084 0.044 0.008 0.000 0.5778 0.084 0.048 0.008 0.000 0.6222 0.084 0.052 0.008 0.000 0.6667 0.084 0.056 0.009 0.000 0.7111 0.084 0.059 0.009 0.000 0.7556 0.084 0.063 0.009 0.000 0.8000 0.084 0.067 0.010 0.000 0.8444 0.084 0.071 0.010 0.000 0.8889 0.084 0.074 0.010 0.000 0.9333 0.084 0.078 0.010 0.000 0.9778 0.084 0.082 0.011 0.000 1.0222 0.084 0.086 0.011 0.000 1.0667 0.084 0.089 0.011 0.000 1.1111 0.084 0.093 0.011 0.000 1.1556 0.084 0.097 0.012 0.000 1.2000 0.084 0.100 0.012 0.000 1.2444 0.084 0.104 0.012 0.000 1.2889 0.084 0.108 0.012 0.000 1.3333 0.084 0.112 0.012 0.000 1.3778 0.084 0.115 0.013 0.000 1.4222 0.084 0.119 0.013 0.000 1.4667 0.084 0.123 0.013 0.000 1.5111 0.084 0.127 0.013 0.000 1.5556 0.084 0.130 0.013 0.000 1.6000 0.084 0.134 0.014 0.000 Sunset Highlands Mixed Use 11/8/2019 1:21:34 PM Page 8 1.6444 0.084 0.138 0.014 0.000 1.6889 0.084 0.142 0.014 0.000 1.7333 0.084 0.145 0.015 0.000 1.7778 0.084 0.149 0.016 0.000 1.8222 0.084 0.153 0.017 0.000 1.8667 0.084 0.157 0.018 0.000 1.9111 0.084 0.160 0.020 0.000 1.9556 0.084 0.164 0.021 0.000 2.0000 0.084 0.168 0.022 0.000 2.0444 0.084 0.171 0.024 0.000 2.0889 0.084 0.175 0.025 0.000 2.1333 0.084 0.179 0.027 0.000 2.1778 0.084 0.183 0.029 0.000 2.2222 0.084 0.186 0.030 0.000 2.2667 0.084 0.190 0.032 0.000 2.3111 0.084 0.194 0.034 0.000 2.3556 0.084 0.198 0.035 0.000 2.4000 0.084 0.201 0.037 0.000 2.4444 0.084 0.205 0.039 0.000 2.4889 0.084 0.209 0.041 0.000 2.5333 0.084 0.213 0.042 0.000 2.5778 0.084 0.216 0.044 0.000 2.6222 0.084 0.220 0.046 0.000 2.6667 0.084 0.224 0.048 0.000 2.7111 0.084 0.228 0.050 0.000 2.7556 0.084 0.231 0.052 0.000 2.8000 0.084 0.235 0.054 0.000 2.8444 0.084 0.239 0.057 0.000 2.8889 0.084 0.242 0.059 0.000 2.9333 0.084 0.246 0.061 0.000 2.9778 0.084 0.250 0.064 0.000 3.0222 0.084 0.254 0.118 0.000 3.0667 0.084 0.257 0.339 0.000 3.1111 0.084 0.261 0.653 0.000 3.1556 0.084 0.265 1.035 0.000 3.2000 0.084 0.269 1.470 0.000 3.2444 0.084 0.272 1.943 0.000 3.2889 0.084 0.276 2.440 0.000 3.3333 0.084 0.280 2.948 0.000 3.3778 0.084 0.284 3.452 0.000 3.4222 0.084 0.287 3.938 0.000 3.4667 0.084 0.291 4.392 0.000 3.5111 0.084 0.295 4.804 0.000 3.5556 0.084 0.299 5.164 0.000 3.6000 0.084 0.302 5.468 0.000 3.6444 0.084 0.306 5.716 0.000 3.6889 0.084 0.310 5.916 0.000 3.7333 0.084 0.313 6.081 0.000 3.7778 0.084 0.317 6.317 0.000 3.8222 0.084 0.321 6.493 0.000 3.8667 0.084 0.325 6.665 0.000 3.9111 0.084 0.328 6.832 0.000 3.9556 0.084 0.332 6.995 0.000 4.0000 0.084 0.336 7.154 0.000 4.0444 0.084 0.340 7.310 0.000 4.0889 0.000 0.000 7.463 0.000 Sunset Highlands Mixed Use 11/8/2019 1:21:34 PM Page 9 ` Bottom Length: 33.00 ft. Bottom Width: 32.00 ft. Material thickness of first layer: 1.5 Material type for first layer: SMMWW 12 in/hr Material thickness of second layer: 0 Material type for second layer: Sand Material thickness of third layer: 0 Material type for third layer: GRAVEL Infiltration On Infiltration rate:0.4 Infiltration safety factor:1 Total Volume Infiltrated (ac-ft.):73.227 Total Volume Through Riser (ac-ft.):7.108 Total Volume Through Facility (ac-ft.):80.335 Percent Infiltrated:91.15 Total Precip Applied to Facility:5.708 Total Evap From Facility:2.436 Underdrain not used Discharge Structure Riser Height:0.5 ft. Riser Diameter:12 in. Element Flows To: Outlet 1 Outlet 2 Detention Vault Bioretention Hydraulic Table Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)Infilt(cfs) 0.0000 0.0311 0.0000 0.0000 0.0000 0.0275 0.0310 0.0003 0.0000 0.0000 0.0549 0.0309 0.0006 0.0000 0.0000 0.0824 0.0307 0.0009 0.0001 0.0001 0.1099 0.0306 0.0012 0.0001 0.0001 0.1374 0.0305 0.0015 0.0002 0.0002 0.1648 0.0304 0.0019 0.0003 0.0003 0.1923 0.0302 0.0022 0.0005 0.0005 0.2198 0.0301 0.0025 0.0006 0.0006 0.2473 0.0300 0.0028 0.0009 0.0009 0.2747 0.0299 0.0031 0.0011 0.0011 0.3022 0.0297 0.0034 0.0014 0.0014 0.3297 0.0296 0.0038 0.0017 0.0017 0.3571 0.0295 0.0041 0.0021 0.0021 0.3846 0.0294 0.0044 0.0025 0.0025 0.4121 0.0292 0.0047 0.0030 0.0030 0.4396 0.0291 0.0051 0.0035 0.0035 0.4670 0.0290 0.0054 0.0040 0.0040 0.4945 0.0289 0.0057 0.0047 0.0047 0.5220 0.0287 0.0061 0.0053 0.0053 0.5495 0.0286 0.0064 0.0060 0.0060 0.5769 0.0285 0.0067 0.0068 0.0068 0.6044 0.0284 0.0071 0.0077 0.0077 0.6319 0.0282 0.0074 0.0085 0.0085 0.6593 0.0281 0.0078 0.0095 0.0095 0.6868 0.0280 0.0081 0.0098 0.0098 0.7143 0.0279 0.0084 0.0098 0.0098 0.7418 0.0277 0.0088 0.0098 0.0098 Sunset Highlands Mixed Use 11/8/2019 1:21:34 PM Page 10 0.7692 0.0276 0.0091 0.0098 0.0098 0.7967 0.0275 0.0095 0.0098 0.0098 0.8242 0.0274 0.0098 0.0098 0.0098 0.8516 0.0272 0.0102 0.0098 0.0098 0.8791 0.0271 0.0105 0.0098 0.0098 0.9066 0.0270 0.0109 0.0098 0.0098 0.9341 0.0269 0.0113 0.0098 0.0098 0.9615 0.0267 0.0116 0.0098 0.0098 0.9890 0.0266 0.0120 0.0098 0.0098 1.0165 0.0265 0.0123 0.0098 0.0098 1.0440 0.0264 0.0127 0.0098 0.0098 1.0714 0.0262 0.0131 0.0098 0.0098 1.0989 0.0261 0.0134 0.0098 0.0098 1.1264 0.0260 0.0138 0.0098 0.0098 1.1538 0.0259 0.0142 0.0098 0.0098 1.1813 0.0257 0.0145 0.0098 0.0098 1.2088 0.0256 0.0149 0.0098 0.0098 1.2363 0.0255 0.0153 0.0098 0.0098 1.2637 0.0254 0.0157 0.0098 0.0098 1.2912 0.0252 0.0160 0.0098 0.0098 1.3187 0.0251 0.0164 0.0098 0.0098 1.3462 0.0250 0.0168 0.0098 0.0098 1.3736 0.0249 0.0172 0.0098 0.0098 1.4011 0.0247 0.0176 0.0098 0.0098 1.4286 0.0246 0.0180 0.0098 0.0098 1.4560 0.0245 0.0183 0.0098 0.0098 1.4835 0.0244 0.0187 0.0098 0.0098 1.5000 0.0242 0.0190 0.0098 0.0098 Bioretention Hydraulic Table Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)To Amended(cfs)Infilt(cfs) 1.5000 0.0311 0.0190 0.0000 0.2987 0.0000 1.5275 0.0312 0.0198 0.0000 0.2987 0.0000 1.5549 0.0313 0.0207 0.0000 0.3041 0.0000 1.5824 0.0314 0.0215 0.0000 0.3095 0.0000 1.6099 0.0316 0.0224 0.0000 0.3148 0.0000 1.6374 0.0317 0.0233 0.0000 0.3202 0.0000 1.6648 0.0318 0.0241 0.0000 0.3256 0.0000 1.6923 0.0319 0.0250 0.0000 0.3309 0.0000 1.7198 0.0321 0.0259 0.0000 0.3363 0.0000 1.7473 0.0322 0.0268 0.0000 0.3417 0.0000 1.7747 0.0323 0.0277 0.0000 0.3471 0.0000 1.8022 0.0324 0.0286 0.0000 0.3524 0.0000 1.8297 0.0326 0.0295 0.0000 0.3578 0.0000 1.8571 0.0327 0.0304 0.0000 0.3632 0.0000 1.8846 0.0328 0.0313 0.0000 0.3685 0.0000 1.9121 0.0329 0.0322 0.0000 0.3739 0.0000 1.9396 0.0331 0.0331 0.0000 0.3793 0.0000 1.9670 0.0332 0.0340 0.0000 0.3847 0.0000 1.9945 0.0333 0.0349 0.0000 0.3900 0.0000 2.0220 0.0334 0.0358 0.0000 0.3954 0.0000 2.0495 0.0336 0.0367 0.0000 0.4008 0.0000 2.0769 0.0337 0.0376 0.0000 0.4062 0.0000 2.1044 0.0338 0.0386 0.0000 0.4115 0.0000 2.1319 0.0339 0.0395 0.0000 0.4169 0.0000 2.1593 0.0341 0.0404 0.0000 0.4223 0.0000 2.1868 0.0342 0.0414 0.0000 0.4276 0.0000 2.2143 0.0343 0.0423 0.0000 0.4330 0.0000 Sunset Highlands Mixed Use 11/8/2019 1:21:34 PM Page 11 2.2418 0.0344 0.0433 0.0000 0.4384 0.0000 2.2692 0.0346 0.0442 0.0000 0.4438 0.0000 2.2967 0.0347 0.0452 0.0000 0.4491 0.0000 2.3242 0.0348 0.0461 0.0000 0.4545 0.0000 2.3516 0.0349 0.0471 0.0000 0.4599 0.0000 2.3791 0.0351 0.0480 0.0000 0.4653 0.0000 2.4066 0.0352 0.0490 0.0000 0.4706 0.0000 2.4341 0.0353 0.0500 0.0000 0.4760 0.0000 2.4615 0.0354 0.0509 0.0000 0.4814 0.0000 2.4890 0.0356 0.0519 0.0000 0.4867 0.0000 2.5000 0.0356 0.0523 0.0000 0.4889 0.0000 Sunset Highlands Mixed Use 11/8/2019 1:21:34 PM Page 12 Surface ` Element Flows To: Outlet 1 Outlet 2 Detention Vault ` Sunset Highlands Mixed Use 11/8/2019 1:21:34 PM Page 13 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area:0.7 Total Impervious Area:0 Mitigated Landuse Totals for POC #1 Total Pervious Area:0.2 Total Impervious Area:0.54 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.027346 5 year 0.045084 10 year 0.058549 25 year 0.077367 50 year 0.092629 100 year 0.108912 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.012299 5 year 0.020184 10 year 0.027161 25 year 0.038409 50 year 0.048859 100 year 0.06137 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 0.033 0.009 1950 0.039 0.012 1951 0.056 0.038 1952 0.019 0.007 1953 0.016 0.009 1954 0.023 0.011 1955 0.035 0.012 1956 0.029 0.013 1957 0.026 0.011 1958 0.026 0.011 Sunset Highlands Mixed Use 11/8/2019 1:22:13 PM Page 14 1959 0.023 0.010 1960 0.044 0.029 1961 0.022 0.011 1962 0.015 0.007 1963 0.021 0.011 1964 0.027 0.010 1965 0.020 0.012 1966 0.018 0.009 1967 0.042 0.012 1968 0.024 0.009 1969 0.023 0.009 1970 0.020 0.010 1971 0.025 0.012 1972 0.043 0.018 1973 0.020 0.011 1974 0.023 0.011 1975 0.033 0.012 1976 0.023 0.011 1977 0.008 0.009 1978 0.019 0.011 1979 0.012 0.007 1980 0.061 0.032 1981 0.018 0.009 1982 0.042 0.022 1983 0.029 0.012 1984 0.018 0.007 1985 0.011 0.010 1986 0.046 0.014 1987 0.042 0.021 1988 0.018 0.008 1989 0.011 0.008 1990 0.117 0.027 1991 0.053 0.032 1992 0.022 0.011 1993 0.021 0.009 1994 0.009 0.006 1995 0.028 0.012 1996 0.067 0.038 1997 0.053 0.040 1998 0.019 0.009 1999 0.073 0.019 2000 0.020 0.012 2001 0.005 0.007 2002 0.028 0.018 2003 0.039 0.009 2004 0.045 0.047 2005 0.030 0.012 2006 0.031 0.011 2007 0.087 0.060 2008 0.092 0.047 2009 0.041 0.014 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.1171 0.0601 2 0.0921 0.0473 3 0.0866 0.0467 Sunset Highlands Mixed Use 11/8/2019 1:22:13 PM Page 15 4 0.0729 0.0400 5 0.0668 0.0384 6 0.0612 0.0375 7 0.0562 0.0318 8 0.0528 0.0315 9 0.0527 0.0293 10 0.0457 0.0268 11 0.0451 0.0215 12 0.0436 0.0208 13 0.0429 0.0189 14 0.0425 0.0183 15 0.0420 0.0178 16 0.0416 0.0144 17 0.0414 0.0141 18 0.0391 0.0132 19 0.0389 0.0122 20 0.0355 0.0121 21 0.0335 0.0121 22 0.0326 0.0121 23 0.0307 0.0120 24 0.0296 0.0120 25 0.0292 0.0120 26 0.0289 0.0117 27 0.0284 0.0115 28 0.0284 0.0115 29 0.0268 0.0115 30 0.0265 0.0112 31 0.0261 0.0110 32 0.0249 0.0109 33 0.0243 0.0109 34 0.0234 0.0108 35 0.0232 0.0108 36 0.0230 0.0108 37 0.0229 0.0108 38 0.0225 0.0106 39 0.0220 0.0106 40 0.0218 0.0099 41 0.0214 0.0099 42 0.0213 0.0098 43 0.0204 0.0096 44 0.0203 0.0095 45 0.0199 0.0094 46 0.0197 0.0093 47 0.0195 0.0093 48 0.0188 0.0093 49 0.0188 0.0089 50 0.0184 0.0089 51 0.0181 0.0088 52 0.0178 0.0087 53 0.0177 0.0086 54 0.0159 0.0084 55 0.0148 0.0083 56 0.0121 0.0073 57 0.0113 0.0072 58 0.0108 0.0069 59 0.0087 0.0066 60 0.0080 0.0065 61 0.0053 0.0058 Sunset Highlands Mixed Use 11/8/2019 1:22:13 PM Page 16 Sunset Highlands Mixed Use 11/8/2019 1:22:13 PM Page 17 Duration Flows The Facility PASSED Flow(cfs)Predev Mit Percentage Pass/Fail 0.0137 18450 4785 25 Pass 0.0145 16091 3401 21 Pass 0.0153 14328 2979 20 Pass 0.0161 12694 2697 21 Pass 0.0169 11182 2398 21 Pass 0.0177 9882 2162 21 Pass 0.0185 8825 1968 22 Pass 0.0193 7843 1795 22 Pass 0.0201 7005 1652 23 Pass 0.0209 6288 1528 24 Pass 0.0216 5679 1434 25 Pass 0.0224 5172 1369 26 Pass 0.0232 4697 1296 27 Pass 0.0240 4278 1213 28 Pass 0.0248 3910 1132 28 Pass 0.0256 3527 1042 29 Pass 0.0264 3183 955 30 Pass 0.0272 2862 865 30 Pass 0.0280 2594 794 30 Pass 0.0288 2353 713 30 Pass 0.0296 2138 649 30 Pass 0.0304 1951 595 30 Pass 0.0312 1796 516 28 Pass 0.0320 1669 476 28 Pass 0.0328 1514 446 29 Pass 0.0336 1343 417 31 Pass 0.0344 1223 391 31 Pass 0.0352 1123 366 32 Pass 0.0360 1042 341 32 Pass 0.0368 969 313 32 Pass 0.0376 910 278 30 Pass 0.0384 838 259 30 Pass 0.0392 766 234 30 Pass 0.0400 704 210 29 Pass 0.0408 635 187 29 Pass 0.0416 570 169 29 Pass 0.0424 488 155 31 Pass 0.0432 425 141 33 Pass 0.0440 376 127 33 Pass 0.0448 341 113 33 Pass 0.0456 307 98 31 Pass 0.0464 270 80 29 Pass 0.0472 235 62 26 Pass 0.0480 196 55 28 Pass 0.0488 171 52 30 Pass 0.0496 145 50 34 Pass 0.0504 125 46 36 Pass 0.0512 107 44 41 Pass 0.0520 95 43 45 Pass 0.0528 84 40 47 Pass 0.0535 71 37 52 Pass 0.0543 61 35 57 Pass 0.0551 55 32 58 Pass Sunset Highlands Mixed Use 11/8/2019 1:22:13 PM Page 18 0.0559 45 28 62 Pass 0.0567 40 22 55 Pass 0.0575 37 20 54 Pass 0.0583 35 17 48 Pass 0.0591 29 14 48 Pass 0.0599 25 7 28 Pass 0.0607 22 0 0 Pass 0.0615 17 0 0 Pass 0.0623 15 0 0 Pass 0.0631 11 0 0 Pass 0.0639 9 0 0 Pass 0.0647 8 0 0 Pass 0.0655 8 0 0 Pass 0.0663 8 0 0 Pass 0.0671 7 0 0 Pass 0.0679 7 0 0 Pass 0.0687 7 0 0 Pass 0.0695 7 0 0 Pass 0.0703 7 0 0 Pass 0.0711 7 0 0 Pass 0.0719 7 0 0 Pass 0.0727 6 0 0 Pass 0.0735 5 0 0 Pass 0.0743 5 0 0 Pass 0.0751 5 0 0 Pass 0.0759 4 0 0 Pass 0.0767 4 0 0 Pass 0.0775 4 0 0 Pass 0.0783 4 0 0 Pass 0.0791 4 0 0 Pass 0.0799 4 0 0 Pass 0.0807 4 0 0 Pass 0.0815 4 0 0 Pass 0.0823 4 0 0 Pass 0.0831 4 0 0 Pass 0.0839 3 0 0 Pass 0.0847 3 0 0 Pass 0.0855 3 0 0 Pass 0.0862 3 0 0 Pass 0.0870 2 0 0 Pass 0.0878 2 0 0 Pass 0.0886 2 0 0 Pass 0.0894 2 0 0 Pass 0.0902 2 0 0 Pass 0.0910 2 0 0 Pass 0.0918 2 0 0 Pass 0.0926 1 0 0 Pass Sunset Highlands Mixed Use 11/8/2019 1:22:13 PM Page 19 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume:0 acre-feet On-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. Off-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. Sunset Highlands Mixed Use 11/8/2019 1:22:13 PM Page 20 LID Report Sunset Highlands Mixed Use 11/8/2019 1:22:40 PM Page 21 Model Default Modifications Total of 0 changes have been made. PERLND Changes No PERLND changes have been made. IMPLND Changes No IMPLND changes have been made. Sunset Highlands Mixed Use 11/8/2019 1:22:40 PM Page 22 Appendix Predeveloped Schematic Sunset Highlands Mixed Use 11/8/2019 1:22:42 PM Page 23 Mitigated Schematic Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 24 Predeveloped UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 Sunset Highlands Mixed Use.wdm MESSU 25 PreSunset Highlands Mixed Use.MES 27 PreSunset Highlands Mixed Use.L61 28 PreSunset Highlands Mixed Use.L62 30 POCSunset Highlands Mixed Use1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 10 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Predeveloped Basin MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 10 C, Forest, Flat 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 10 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* 10 0 0 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 25 PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 10 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 10 0 4.5 0.08 400 0.05 0.5 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 10 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 10 0.2 0.5 0.35 6 0.5 0.7 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 10 0 0 0 0 2.5 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS END IWAT-STATE1 Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 26 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Predeveloped Basin*** PERLND 10 0.7 COPY 501 12 PERLND 10 0.7 COPY 501 13 ******Routing****** END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1.167 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1.167 IMPLND 1 999 EXTNL PREC Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 27 WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** COPY 501 OUTPUT MEAN 1 1 48.4 WDM 501 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 12 MASS-LINK 13 PERLND PWATER IFWO 0.083333 COPY INPUT MEAN END MASS-LINK 13 END MASS-LINK END RUN Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 28 Mitigated UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 Sunset Highlands Mixed Use.wdm MESSU 25 MitSunset Highlands Mixed Use.MES 27 MitSunset Highlands Mixed Use.L61 28 MitSunset Highlands Mixed Use.L62 30 POCSunset Highlands Mixed Use1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 16 IMPLND 1 IMPLND 4 IMPLND 8 GENER 2 RCHRES 1 RCHRES 2 RCHRES 3 COPY 1 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Detention Vault MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** 2 24 END OPCODE PARM # # K *** 2 0. END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 16 C, Lawn, Flat 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 29 # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 16 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* 16 0 0 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 16 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 16 0 4.5 0.03 400 0.05 0.5 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 16 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 16 0.1 0.25 0.25 6 0.5 0.25 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 16 0 0 0 0 2.5 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 1 ROADS/FLAT 1 1 1 27 0 4 ROOF TOPS/FLAT 1 1 1 27 0 8 SIDEWALKS/FLAT 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 1 0 0 1 0 0 0 4 0 0 1 0 0 0 8 0 0 1 0 0 0 END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 1 0 0 4 0 0 0 1 9 4 0 0 4 0 0 0 1 9 8 0 0 4 0 0 0 1 9 END PRINT-INFO IWAT-PARM1 Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 30 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** 1 0 0 0 0 0 4 0 0 0 0 0 8 0 0 0 0 0 END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 1 400 0.01 0.1 0.1 4 400 0.01 0.1 0.1 8 400 0.01 0.1 0.1 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 1 0 0 4 0 0 8 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 1 0 0 4 0 0 8 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Roof and Pervious Pave*** PERLND 16 0.04 RCHRES 3 2 PERLND 16 0.04 RCHRES 3 3 IMPLND 1 0.03 RCHRES 3 5 IMPLND 4 0.19 RCHRES 3 5 Water Quality*** PERLND 16 0.16 RCHRES 1 2 PERLND 16 0.16 RCHRES 1 3 IMPLND 1 0.3 RCHRES 1 5 IMPLND 8 0.02 RCHRES 1 5 ******Routing****** PERLND 16 0.04 COPY 1 12 IMPLND 1 0.03 COPY 1 15 IMPLND 4 0.19 COPY 1 15 PERLND 16 0.04 COPY 1 13 RCHRES 2 1 RCHRES 3 7 RCHRES 2 COPY 1 17 RCHRES 1 1 RCHRES 3 7 RCHRES 1 COPY 1 17 RCHRES 1 1 RCHRES 2 8 RCHRES 3 1 COPY 501 16 END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 GENER 2 OUTPUT TIMSER .0011111 RCHRES 1 EXTNL OUTDGT 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 31 END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** 1 Surface ` 3 1 1 1 28 0 1 2 ` 2 1 1 1 28 0 1 3 Detention Vault 1 1 1 1 28 0 1 END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** 1 1 0 0 0 0 0 0 0 0 0 2 1 0 0 0 0 0 0 0 0 0 3 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* 1 4 0 0 0 0 0 0 0 0 0 1 9 2 4 0 0 0 0 0 0 0 0 0 1 9 3 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** 1 0 1 0 0 4 5 6 0 0 0 1 0 0 0 2 1 2 2 2 2 0 1 0 0 4 5 0 0 0 0 0 0 0 0 2 2 2 2 2 3 0 1 0 0 4 0 0 0 0 0 0 0 0 0 2 2 2 2 2 END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** 1 1 0.01 0.0 0.0 0.5 0.0 2 2 0.01 0.0 0.0 0.5 0.0 3 3 0.02 0.0 0.0 0.5 0.0 END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> 1 0 4.0 5.0 6.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2 0 4.0 5.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3 0 4.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 END HYDR-INIT END RCHRES SPEC-ACTIONS *** User-Defined Variable Quantity Lines *** addr *** <------> *** kwd varnam optyp opn vari s1 s2 s3 tp multiply lc ls ac as agfn *** <****> <----> <----> <-> <----><-><-><-><-><--------> <><-> <><-> <--> *** UVQUAN vol2 RCHRES 2 VOL 4 UVQUAN v2m2 GLOBAL WORKSP 1 3 UVQUAN vpo2 GLOBAL WORKSP 2 3 UVQUAN v2d2 GENER 2 K 1 3 *** User-Defined Target Variable Names *** addr or addr or *** <------> <------> Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 32 *** kwd varnam ct vari s1 s2 s3 frac oper vari s1 s2 s3 frac oper <****> <----><-> <----><-><-><-> <---> <--> <----><-><-><-> <---> <--> UVNAME v2m2 1 WORKSP 1 1.0 QUAN UVNAME vpo2 1 WORKSP 2 1.0 QUAN UVNAME v2d2 1 K 1 1.0 QUAN *** opt foplop dcdts yr mo dy hr mn d t vnam s1 s2 s3 ac quantity tc ts rp <****><-><--><><-><--> <> <> <> <><><> <----><-><-><-><-><--------> <> <-><-> GENER 2 v2m2 = 775. *** Compute remaining available pore space GENER 2 vpo2 = v2m2 GENER 2 vpo2 -= vol2 *** Check to see if VPORA goes negative; if so set VPORA = 0.0 IF (vpo2 < 0.0) THEN GENER 2 vpo2 = 0.0 END IF *** Infiltration volume GENER 2 v2d2 = vpo2 END SPEC-ACTIONS FTABLES FTABLE 3 92 4 Depth Area Volume Outflow1 Velocity Travel Time*** (ft) (acres) (acre-ft) (cfs) (ft/sec) (Minutes)*** 0.000000 0.084091 0.000000 0.000000 0.044444 0.084091 0.003737 0.002346 0.088889 0.084091 0.007475 0.003317 0.133333 0.084091 0.011212 0.004063 0.177778 0.084091 0.014949 0.004692 0.222222 0.084091 0.018687 0.005245 0.266667 0.084091 0.022424 0.005746 0.311111 0.084091 0.026162 0.006206 0.355556 0.084091 0.029899 0.006635 0.400000 0.084091 0.033636 0.007037 0.444444 0.084091 0.037374 0.007418 0.488889 0.084091 0.041111 0.007780 0.533333 0.084091 0.044848 0.008126 0.577778 0.084091 0.048586 0.008458 0.622222 0.084091 0.052323 0.008777 0.666667 0.084091 0.056061 0.009085 0.711111 0.084091 0.059798 0.009383 0.755556 0.084091 0.063535 0.009672 0.800000 0.084091 0.067273 0.009952 0.844444 0.084091 0.071010 0.010225 0.888889 0.084091 0.074747 0.010491 0.933333 0.084091 0.078485 0.010750 0.977778 0.084091 0.082222 0.011003 1.022222 0.084091 0.085960 0.011250 1.066667 0.084091 0.089697 0.011492 1.111111 0.084091 0.093434 0.011729 1.155556 0.084091 0.097172 0.011961 1.200000 0.084091 0.100909 0.012189 1.244444 0.084091 0.104646 0.012413 1.288889 0.084091 0.108384 0.012632 1.333333 0.084091 0.112121 0.012848 1.377778 0.084091 0.115859 0.013061 1.422222 0.084091 0.119596 0.013270 1.466667 0.084091 0.123333 0.013476 1.511111 0.084091 0.127071 0.013678 1.555556 0.084091 0.130808 0.013878 1.600000 0.084091 0.134545 0.014075 1.644444 0.084091 0.138283 0.014269 1.688889 0.084091 0.142020 0.014736 1.733333 0.084091 0.145758 0.015511 1.777778 0.084091 0.149495 0.016461 1.822222 0.084091 0.153232 0.017542 1.866667 0.084091 0.156970 0.018729 1.911111 0.084091 0.160707 0.020007 1.955556 0.084091 0.164444 0.021361 2.000000 0.084091 0.168182 0.022781 2.044444 0.084091 0.171919 0.024259 Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 33 2.088889 0.084091 0.175657 0.025788 2.133333 0.084091 0.179394 0.027361 2.177778 0.084091 0.183131 0.028973 2.222222 0.084091 0.186869 0.030618 2.266667 0.084091 0.190606 0.032292 2.311111 0.084091 0.194343 0.033992 2.355556 0.084091 0.198081 0.035712 2.400000 0.084091 0.201818 0.037450 2.444444 0.084091 0.205556 0.039202 2.488889 0.084091 0.209293 0.040965 2.533333 0.084091 0.213030 0.042737 2.577778 0.084091 0.216768 0.044514 2.622222 0.084091 0.220505 0.046294 2.666667 0.084091 0.224242 0.048196 2.711111 0.084091 0.227980 0.050338 2.755556 0.084091 0.231717 0.052521 2.800000 0.084091 0.235455 0.054743 2.844444 0.084091 0.239192 0.057005 2.888889 0.084091 0.242929 0.059306 2.933333 0.084091 0.246667 0.061644 2.977778 0.084091 0.250404 0.064020 3.022222 0.084091 0.254141 0.118030 3.066667 0.084091 0.257879 0.339130 3.111111 0.084091 0.261616 0.653381 3.155556 0.084091 0.265354 1.035716 3.200000 0.084091 0.269091 1.470318 3.244444 0.084091 0.272828 1.943301 3.288889 0.084091 0.276566 2.440852 3.333333 0.084091 0.280303 2.948784 3.377778 0.084091 0.284040 3.452683 3.422222 0.084091 0.287778 3.938390 3.466667 0.084091 0.291515 4.392693 3.511111 0.084091 0.295253 4.804191 3.555556 0.084091 0.298990 5.164284 3.600000 0.084091 0.302727 5.468282 3.644444 0.084091 0.306465 5.716611 3.688889 0.084091 0.310202 5.916115 3.733333 0.084091 0.313939 6.081438 3.777778 0.084091 0.317677 6.317430 3.822222 0.084091 0.321414 6.493643 3.866667 0.084091 0.325152 6.665158 3.911111 0.084091 0.328889 6.832330 3.955556 0.084091 0.332626 6.995476 4.000000 0.084091 0.336364 7.154871 4.044444 0.084091 0.340101 7.310764 END FTABLE 3 FTABLE 2 56 5 Depth Area Volume Outflow1 Outflow2 Velocity Travel Time*** (ft) (acres) (acre-ft) (cfs) (cfs) (ft/sec) (Minutes)*** 0.000000 0.031061 0.000000 0.000000 0.000000 0.027473 0.030986 0.000305 0.000000 0.000000 0.054945 0.030861 0.000612 0.000000 0.000031 0.082418 0.030736 0.000921 0.000000 0.000069 0.109890 0.030611 0.001231 0.000000 0.000129 0.137363 0.030486 0.001542 0.000000 0.000213 0.164835 0.030361 0.001856 0.000000 0.000326 0.192308 0.030236 0.002170 0.000000 0.000469 0.219780 0.030112 0.002487 0.000000 0.000644 0.247253 0.029987 0.002805 0.000000 0.000855 0.274725 0.029862 0.003124 0.000000 0.001104 0.302198 0.029737 0.003445 0.000000 0.001391 0.329670 0.029612 0.003768 0.000000 0.001720 0.357143 0.029487 0.004092 0.000000 0.002093 0.384615 0.029362 0.004418 0.000000 0.002510 0.412088 0.029237 0.004745 0.000000 0.002973 0.439560 0.029113 0.005074 0.000000 0.003485 0.467033 0.028988 0.005404 0.000000 0.004047 0.494505 0.028863 0.005736 0.000000 0.004660 0.521978 0.028738 0.006070 0.000000 0.005326 Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 34 0.549451 0.028613 0.006405 0.000000 0.006047 0.576923 0.028488 0.006742 0.000000 0.006823 0.604396 0.028363 0.007080 0.000000 0.007656 0.631868 0.028238 0.007420 0.000000 0.008547 0.659341 0.028114 0.007761 0.000000 0.009499 0.686813 0.027989 0.008104 0.000000 0.009778 0.714286 0.027864 0.008449 0.000000 0.009778 0.741758 0.027739 0.008795 0.000000 0.009778 0.769231 0.027614 0.009143 0.000000 0.009778 0.796703 0.027489 0.009492 0.000000 0.009778 0.824176 0.027364 0.009843 0.000000 0.009778 0.851648 0.027239 0.010195 0.000000 0.009778 0.879121 0.027115 0.010549 0.000000 0.009778 0.906593 0.026990 0.010905 0.000000 0.009778 0.934066 0.026865 0.011262 0.000000 0.009778 0.961538 0.026740 0.011621 0.000000 0.009778 0.989011 0.026615 0.011981 0.000000 0.009778 1.016484 0.026490 0.012343 0.000000 0.009778 1.043956 0.026365 0.012706 0.000000 0.009778 1.071429 0.026240 0.013071 0.000000 0.009778 1.098901 0.026116 0.013438 0.000000 0.009778 1.126374 0.025991 0.013806 0.000000 0.009778 1.153846 0.025866 0.014175 0.000000 0.009778 1.181319 0.025741 0.014547 0.000000 0.009778 1.208791 0.025616 0.014919 0.000000 0.009778 1.236264 0.025491 0.015294 0.000000 0.009778 1.263736 0.025366 0.015670 0.000000 0.009778 1.291209 0.025241 0.016047 0.000000 0.009778 1.318681 0.025117 0.016426 0.000000 0.009778 1.346154 0.024992 0.016807 0.000000 0.009778 1.373626 0.024867 0.017189 0.000000 0.009778 1.401099 0.024742 0.017573 0.000000 0.009778 1.428571 0.024617 0.017958 0.000000 0.009778 1.456044 0.024492 0.018345 0.000000 0.009778 1.483516 0.024367 0.018734 0.000000 0.009778 1.500000 0.024242 0.039832 0.000000 0.009778 END FTABLE 2 FTABLE 1 38 6 Depth Area Volume Outflow1 Outflow2 outflow 3 Velocity Travel Time*** (ft) (acres) (acre-ft) (cfs) (cfs) (cfs) (ft/sec) (Minutes)*** 0.000000 0.024242 0.000000 0.000000 0.000000 0.000000 0.027473 0.031185 0.000855 0.000000 0.298706 0.000000 0.054945 0.031310 0.001713 0.000000 0.304078 0.000000 0.082418 0.031435 0.002575 0.000000 0.309451 0.000000 0.109890 0.031560 0.003441 0.000000 0.314823 0.000000 0.137363 0.031685 0.004309 0.000000 0.320196 0.000000 0.164835 0.031810 0.005182 0.000000 0.325568 0.000000 0.192308 0.031935 0.006057 0.000000 0.330940 0.000000 0.219780 0.032060 0.006936 0.000000 0.336313 0.000000 0.247253 0.032184 0.007819 0.000000 0.341685 0.000000 0.274725 0.032309 0.008705 0.000000 0.347058 0.000000 0.302198 0.032434 0.009594 0.000000 0.352430 0.000000 0.329670 0.032559 0.010487 0.000000 0.357802 0.000000 0.357143 0.032684 0.011383 0.000000 0.363175 0.000000 0.384615 0.032809 0.012283 0.000000 0.368547 0.000000 0.412088 0.032934 0.013186 0.000000 0.373920 0.000000 0.439560 0.033059 0.014092 0.000000 0.379292 0.000000 0.467033 0.033183 0.015002 0.000000 0.384665 0.000000 0.494505 0.033308 0.015915 0.000000 0.390037 0.000000 0.521978 0.033433 0.016832 0.034569 0.395409 0.000000 0.549451 0.033558 0.017752 0.116539 0.400782 0.000000 0.576923 0.033683 0.018676 0.225672 0.406154 0.000000 0.604396 0.033808 0.019603 0.355486 0.411527 0.000000 0.631868 0.033933 0.020534 0.501498 0.416899 0.000000 0.659341 0.034058 0.021468 0.659695 0.422271 0.000000 0.686813 0.034182 0.022405 0.826090 0.427644 0.000000 0.714286 0.034307 0.023346 0.996598 0.433016 0.000000 Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 35 0.741758 0.034432 0.024290 1.167052 0.438389 0.000000 0.769231 0.034557 0.025238 1.333311 0.443761 0.000000 0.796703 0.034682 0.026189 1.491422 0.449133 0.000000 0.824176 0.034807 0.027143 1.637810 0.454506 0.000000 0.851648 0.034932 0.028101 1.769522 0.459878 0.000000 0.879121 0.035057 0.029063 1.884482 0.465251 0.000000 0.906593 0.035181 0.030027 1.981777 0.470623 0.000000 0.934066 0.035306 0.030996 2.061968 0.475995 0.000000 0.961538 0.035431 0.031967 2.127417 0.481368 0.000000 0.989011 0.035556 0.032942 2.182633 0.486740 0.000000 1.000000 0.035606 0.033333 2.263538 0.488889 0.000000 END FTABLE 1 END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1.167 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1.167 IMPLND 1 999 EXTNL PREC WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP WDM 2 PREC ENGL 1.167 RCHRES 1 EXTNL PREC WDM 1 EVAP ENGL 0.5 RCHRES 1 EXTNL POTEV WDM 1 EVAP ENGL 0.76 RCHRES 2 EXTNL POTEV END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** RCHRES 3 HYDR RO 1 1 1 WDM 1000 FLOW ENGL REPL RCHRES 3 HYDR STAGE 1 1 1 WDM 1003 STAG ENGL REPL COPY 1 OUTPUT MEAN 1 1 48.4 WDM 701 FLOW ENGL REPL COPY 501 OUTPUT MEAN 1 1 48.4 WDM 801 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 2 PERLND PWATER SURO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 2 MASS-LINK 3 PERLND PWATER IFWO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 3 MASS-LINK 5 IMPLND IWATER SURO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 5 MASS-LINK 7 RCHRES OFLOW OVOL 1 RCHRES INFLOW IVOL END MASS-LINK 7 MASS-LINK 8 RCHRES OFLOW OVOL 2 RCHRES INFLOW IVOL END MASS-LINK 8 MASS-LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 12 MASS-LINK 13 PERLND PWATER IFWO 0.083333 COPY INPUT MEAN END MASS-LINK 13 MASS-LINK 15 IMPLND IWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 15 Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 36 MASS-LINK 16 RCHRES ROFLOW COPY INPUT MEAN END MASS-LINK 16 MASS-LINK 17 RCHRES OFLOW OVOL 1 COPY INPUT MEAN END MASS-LINK 17 END MASS-LINK END RUN Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 37 Predeveloped HSPF Message File Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 38 Mitigated HSPF Message File Sunset Highlands Mixed Use 11/8/2019 1:22:43 PM Page 39 Disclaimer Legal Notice This program and accompanying documentation are provided 'as-is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by End User. Clear Creek Solutions Inc. and the governmental licensee or sublicensees disclaim all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall Clear Creek Solutions Inc. be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the like) arising out of the use of, or inability to use this program even if Clear Creek Solutions Inc. or their authorized representatives have been advised of the possibility of such damages. Software Copyright © by : Clear Creek Solutions, Inc. 2005-2019; All Rights Reserved. Clear Creek Solutions, Inc. 6200 Capitol Blvd. Ste F Olympia, WA. 98501 Toll Free 1(866)943-0304 Local (360)943-0304 www.clearcreeksolutions.com Preliminary Technical Information Report Sunset Highlands Mixed Use 2190210.10 Appendix D Geotechnical Engineering Report South Sound Geotechnical Consulting February 12, 2018 ADF Properties, LLC 15007 Woodinville Redmond Road, Suite A Woodinville, WA 98072 Attention: Mr. Dale Fonk Subject: Geotechnical Engineering Report Sunset Highlands Mixed Use Development 4409 NE Sunset Boulevard Renton, Washington SSGC Project No. 18003 Mr. Fonk, South Sound Geotechnical Consulting (SSGC) has completed a geotechnical assessment for the planned mixed use development at the above address. Our services have been completed in general conformance with our proposal P17092 (dated November 27 2017) and authorized per signature of our services agreement. Our scope of services included completion of five test pits and two infiltration tests, laboratory testing, engineering analyses, and preparation of this report. PROJECT INFORMATION Mixed use development is planned on property at 4409 NE Sunset Boulevard in Renton, Washington. The property is on the south side of the street and encompasses approximately 0.8 acres. We understand two multi-family buildings are planned with two separate retail spaces. Residential buildings will be three-story structures, with retail buildings anticipated to be one- to two-story structures. Buildings will be supported on conventional spread footing foundations with concrete slab-on-grade floors. Porous pavements are being considered to facilitate stormwater control. SITE CONDITIONS The property is currently vacant and covered with principally grass and weeds. It slopes gently down to the south (from street grade of Sunset Boulevard) with overall elevations change on the order of 5 (+/-) feet. A wetland borders the southern property boundary. SUBSURFACE CONDITIONS Subsurface conditions were characterized by completing five (5) test pits on the site on January 24, 2018. Test pits were advanced to final depths between about 5 and 6 feet below existing ground surface. Approximate locations of the explorations are shown on Figure 1, Exploration Plan. Logs of the test pits are provided in Appendix A. A summary description of observed subgrade conditions is provided below. Geotechnical Engineering Report SSGC Sunset Highlands Mixed-Use Development NE Sunset Boulevard Renton, Washington SSGC Project No. 18003 February 12, 2018 2 Soil Conditions Surface topsoil and/or fill was observed in all test pits and ranged in depth from about 1 to 1.5 feet at the test pit locations. We understand the site was previously developed as a single-family residence, and therefore thicker fill sections may locally be present in other areas. Native soil below the topsoil/fill was fine-medium sand with silt, to silty sand. These soils were in a loose to medium dense condition and extended to depths between 2.5 to 4 feet in the test pits. These soils are interpreted to represent alluvium outwash or reworked sandy glacial till. Below these soils was silty sand with gravel in a medium dense to dense condition that extended to the bottom of the test pits. This soil is considered sandy glacial till. Groundwater Conditions Seepage was observed in all of the test pits at depths between about 2.5 to 3.5 feet. The dense glacial till below the upper sand is considered impermeable to vertical groundwater flow and can cause perched groundwater conditions during the wetter seasons of the year. Groundwater levels will fluctuate due to seasonal precipitation variations and on- and off-site drainage patterns. Geologic Setting Soils within the project area have been classified by the NRCS in the Soil Survey of King County Area, Washington. Surface soils on the site are mapped as Ragnar -Indianola Association. This soil is described as fine sandy loam and loamy fine sand that formed on glacial terraces near streams. Glacial till (Alderwood and Everett soils) are mapped nearby the property. Upper sand soils observed in the test pit appear to confirm the mapped soil type, with dense glacial till below. GEOTECHNICAL DESIGN CONSIDERATIONS The development is considered feasible based on observed soil conditions in the test pits. Properly prepared native soils can be used for support of conventional spread footing foundations, floor slabs, and pavements. Infiltration to assist in stormwater control will be difficult at this site. The dense glacial till at fairly shallow depth will create a barrier to vertical groundwater flow as observed by shallow seepage in test pits. Some infiltration potential is present in the looser upper sands, but the limited thickness of these layers will most likely only support porous pavements or shallow dispersion type infiltration facilities. Recommendations presented in the following sections should be considered general and may require modifications when earthwork and grading occur. They are based upon the subsurface conditions observed in the test pits and the assumption that finish site grades will be similar to existing grades. It should be noted that subsurface conditions across the site may vary from those depicted on the exploration logs and can change with time. Therefore, proper site preparation will depend upon the Geotechnical Engineering Report SSGC Sunset Highlands Mixed-Use Development NE Sunset Boulevard Renton, Washington SSGC Project No. 18003 February 12, 2018 3 weather and soil conditions encountered at the time of construction. We recommend SSGC review final plans and further assess subgrade conditions at the time of construction, as warranted. General Site Preparation Site grading and earthwork should include procedures to control surface water runoff. Grading the site without adequate drainage control measures may negatively impact site soils, resulting in increased export of impacted soil and import of fill materials, thereby potentially increasing the cost of the earthwork and subgrade preparation phases of the project. Site grading should include removal (stripping) of topsoil and any fill encountered, or very loose or soft soils in building and pavement areas. Subgrades should consist of firm, undisturbed native soils following stripping. General Subgrade Preparation Subgrades in building footprints and pavement areas should consist of firm, undisturbed native soil. We recommend exposed subgrades in building and conventional pavement areas are proofrolled using a large roller, loaded dump truck, or other mechanical equipment to assess subgrade conditions following stripping. Proofrolling efforts should result in the upper 1 foot of subgrade soils in building and conventional pavement areas achieving a compaction level of at least 95 percent of the maximum dry density (MDD) per the ASTM D1557 test method. Wet, loose, or soft subgrades that cannot achieve this compaction level should be removed (over-excavated) and replaced with structural fill. The depth of over-excavation should be based on soil conditions at the time of construction. A representative of SSGC should be present to assess subgrade conditions during proofrolling. Subgrade preparation guidelines for porous (pervious) pavements typically recommend limiting or eliminating compaction of subgrade so densification and reduction of infiltration capacity will not occur. Subgrades in porous (pervious) pavement areas should not be proofrolled following stripping. Probing of porous pavement subgrades should be completed to identify soft or loose areas that should be remediated. Grading and Drainage Positive drainage should be provided during construction and maintained throughout the life of the development. Allowing surface water into cut or fill areas, utility trenches and building footprints should be prevented. Geotechnical Engineering Report SSGC Sunset Highlands Mixed-Use Development NE Sunset Boulevard Renton, Washington SSGC Project No. 18003 February 12, 2018 4 Structural Fill Materials The suitability of soil for use as structural fill will depend on the gradation and moisture content of the soil when it is placed. Soils with higher fines content (soil fraction passing the U.S. No. 200 sieve) will become sensitive with higher moisture content. It is often difficult to achieve adequate compaction if soil moisture is outside of optimum ranges for soils that contain more than about 5 percent fines. Site Soils: Topsoil or organic rich soils are not considered suitable as structural fill. Native soils observed could be suitable for use as structural fill provided they can be moisture conditioned to within optimal ranges. Some of the native soils have considerable fine (silt) content and therefore will be moisture sensitive and difficult to use as structural fill. Optimum moisture is considered within about +/- 2 percent of the moisture content required to achieve the maximum density per the ASTM D-1557 test method. If moisture content is higher or lower than optimum, soils would need to be dried or wetted prior to placement as structural fill. Import Fill Materials: We recommend import structural fill placed during dry weather consist of material which meets the specifications for Gravel Borrow as described in Section 9-03.14(1) of the 2016 Washington State Department of Transportation (WSDOT) Specifications for Road, Bridge, and Municipal Construction (Publication M 41-10). Gravel Borrow should be protected from disturbance if exposed to wet conditions after placement. During wet weather, or for backfill on wet subgrades, import soil suitable for compaction in wetter conditions should be provided. Imported fill for use in wet conditions should conform to specifications for Select Borrow as described in Section 9-03.14(2), or Crushed Surfacing per Section 9-03.9(3) of the 2016 WSDOT M-41 manual, with the modification that a maximum of 5 percent by weight shall pass the U.S. No. 200 sieve for these soil types. Structural fill placement and compaction is weather-dependent. Delays due to inclement weather are common, even when using select granular fill. We recommend site grading and earthwork be scheduled for the drier months of the year. Structural fill should not consist of frozen material. Structural Fill Placement We recommend structural fill is placed in lifts not exceeding about 10 inches in loose measure. It may be necessary to adjust lift thickness based on site and fill conditions during placement and compaction. Finer grained soil used as structural fill and/or lighter weight compaction equipment may require significantly thinner lifts to attain required compaction levels. Granular soil with lower fines contents could potentially be placed in thicker lifts if they can be adequately compacted. Structural fill should be compacted to attain the recommended levels presented in Table 1, Compaction Criteria. Geotechnical Engineering Report SSGC Sunset Highlands Mixed-Use Development NE Sunset Boulevard Renton, Washington SSGC Project No. 18003 February 12, 2018 5 Table 1. Compaction Criteria Fill Application Compaction Criteria* Footing areas 95 % Upper 2 feet in pavement areas, slabs and sidewalks, and utility trenches 95 % Below 2 feet in pavement areas, slabs and sidewalks, and utility trenches 92 % Utility trenches or general fill in non-paved or -building areas 90 % *Per the ASTM D 1557 test method. Trench backfill within about 2 feet of utility lines should not be over-compacted to reduce the risk of damage to the line. In some instances the top of the utility line may be within 2 feet of the surface. Backfill in these circumstances should be compacted to a firm and unyielding condition. We recommend fill procedures include maintaining grades that promote drainage and do not allow ponding of water within the fill area. The contractor should protect compacted fill subgrades from disturbance during wet weather. In the event of rain during structural fill placement, the exposed fill surface should be allowed to dry prior to placement of additional fill. Alternatively, the we t soil can be removed. We recommend consideration is given to protecting haul routes and other high traffic areas with free-draining granular fill material (i.e. sand and gravel containing less than 5 percent fines) or quarry spalls to reduce the potential for disturbance to the subgrade during inclement weather. Earthwork Procedures Conventional earthmoving equipment should be suitable for earthwork at this site. Earthwork may be difficult during periods of wet weather or if elevated soil moisture is present. Excavated site soils may not be suitable as structural fill depending on the soil moisture content and weather conditions at the time of earthwork. If soils are stockpiled and wet weather is anticipated, the stockpile should be protected with securely anchored plastic sheeting. If stockpiled soils become wet and unusable, it will become necessary to import clean, granular soils to complete wet weather site work. Wet or disturbed subgrade soils should be over-excavated to expose firm, non-yielding, non-organic soils and backfilled with compacted structural fill. We recommend the earthwork portion of this project be completed during extended periods of dry weather. If earthwork is completed during the wet season (typically October through May) it may be necessary to take extra measures to protect subgrade soils. If earthwork takes place during freezing conditions, we recommend the exposed subgrade is allowed to thaw and re-compacted prior to placing subsequent lifts of structural fill. Alternatively, the frozen soil can be removed to unfrozen soil and replaced with structural fill. Geotechnical Engineering Report SSGC Sunset Highlands Mixed-Use Development NE Sunset Boulevard Renton, Washington SSGC Project No. 18003 February 12, 2018 6 The contractor is responsible for designing and constructing stable, temporary excavations (including utility trenches) as required to maintain stability of excavation sides and bottoms. Excavations should be sloped or shored in the interest of safety following local and federal regulations, including current OSHA excavation and trench safety standards. Temporary excavation cuts should be sloped at inclinations of 1.5H:1V (Horizontal:Vertical) or flatter, unless the contractor can demonstrate the safety of steeper cut slopes. Permanent cut and fill slopes should be inclined at 2H:1V, or flatter. A qualified geotechnical engineer and materials testing firm should be retained during the construction phase of the project to observe earthwork operations and to perform necessary tests and observations during subgrade preparation, placement and compaction of structural fill, and backfilling of excavations. Foundations Foundations can be placed on native subgrade soils or on a zone of structural fill above prepared subgrades as described in this report. The following recommendations are for conventional spread footing foundations: Bearing Capacity (net allowable): 2,500 pounds per square foot (psf) for footings supported on firm native soils or structural fill over native subgrades prepared as described in this report. Footing Width (Minimum): 18 inches (Strip) 24 inches (Column) Embedment Depth (Minimum): 18 inches (Exterior) 12 inches (Interior) Settlement: Total: < 1 inch Differential: < 1/2 inch (over 30 feet) Allowable Lateral Passive Resistance: 325 psf/ft* (below 12 inches) Allowable Coefficient of Friction: 0.35* *These values include a factor of safety of approximately 1.5. The net allowable bearing pressures presented above may be increased by one -third to resist transient, dynamic loads such as wind or seismic forces. Lateral resistance to footings should be ignored in the upper 12-inches from exterior finish grade unless restricted. Geotechnical Engineering Report SSGC Sunset Highlands Mixed-Use Development NE Sunset Boulevard Renton, Washington SSGC Project No. 18003 February 12, 2018 7 Foundation Construction Considerations All foundation subgrades should be free of water and loose soil prior to placing concrete , and should be prepared as recommended in this report. Concrete should be placed soon after excavating and compaction to reduce disturbance to bearing soils. Should soils at foundation level become excessively dry, disturbed, saturated, or frozen, the affected soil should be removed prior to placing concrete. We recommend SSGC observe all foundation subgrades prior to placement of concrete. Foundation Drainage Ground surface adjacent foundations should be sloped away to facilitate drainage. We recommend footing drains are installed around perimeter footings. Footing drains should include a minimum 4- inch diameter perforated rigid plastic or metal drain line installed along the exterior base of the footing. The perforated drain lines should be connected to a tight line pipe that discharges to an approved storm drain receptor. The drain line should be surrounded by a zone of clean, free-draining granular material having less than 5 percent passing the No. 200 sieve or meeting the requirements of section 9-03.12(2) “Gravel Backfill for Walls” in the 2016 WSDOT Standard Specifications for Road, Bridge, and Municipal Construction manual (M41-10). The free-draining aggregate zone should be at least 12 inches wide and wrapped in filter fabric. The granular fill should extend to within 6 inches of final grade where it should be capped with compacted fill containing sufficient fines to reduce infiltration of surface water into the footing drains. Alternately, the ground surface can be paved with asphalt or concrete. Cleanouts are recommended for maintenance of the drain system. On-Grade Floor Slabs On-grade floor slabs should be placed on native soils or structural fill prepared as described in this report. We recommend a modulus subgrade reaction of 225 pounds per square inch per inch (psi/in) for native soil or compacted granular structural fill over properly prepared native soil. We recommend a capillary break is provided between the prepared subgrade and bottom of slab. Capillary break material should be a minimum of 4 inches thick and consist of compacted clean, free- draining, well graded course sand and gravel. The capillary break material should contain less than 5 percent fines, based on that soil fraction passing the U.S. No. 4 sieve. Alternatively, a clean angular gravel such as No. 7 aggregate per Section 9-03.1(4) C of the 2016 WSDOT (M41-10) manual could be used for this purpose. We recommend positive separations and/or isolation joints are provided between slabs and foundations, and columns or utility lines to allow independent movement where needed. Backfill in interior trenches beneath slabs should be compacted in accordance with recommendations presented in this report. A vapor retarder should be considered beneath concrete slabs that will be covered with moisture sensitive or impervious coverings (such as tile, wood, etc.), or when the slab will support equipment or stored Geotechnical Engineering Report SSGC Sunset Highlands Mixed-Use Development NE Sunset Boulevard Renton, Washington SSGC Project No. 18003 February 12, 2018 8 materials sensitive to moisture. We recommend the slab designer refer to ACI 302 and/or ACI 360 for procedures and limitations regarding the use and placement of vapor retarders. Seismic Considerations Seismic parameters and values in Table 2 are recommended based on the 2015 International Building Code (IBC). Table 2. Seismic Parameters PARAMETER VALUE 2015 International Building Code (IBC) Site Classification1 D Ss Spectral Acceleration for a Short Period 1.408 S1 Spectral Acceleration for a 1-Second Period 0.530g Fa Site Coefficient for a Short Period 1.00 Fv Site Coefficient for a 1-Second Period 1.5 1 Note: In general accordance with 2015 International Building Code, Section 1613.3.1 for risk categories I,II,III. IBC Site Class is based on characteristics of the upper 100 feet of the subsurface profile. Ss, S1, Fa, and Fv values based on the USGS US Seismic Design Maps website using referenced site latitude and longitude. Liquefaction Soil liquefaction is a condition where loose, typically granular soils located below the groundwater surface lose strength during ground shaking, and is often associated with earthquakes. The King County “Liquefaction Susceptibility” Map (Map 11-5, dated May 2010) depicts the site in an area with very low to low liquefaction potential. Native soils at fairly shallow depth consist of dense to very dense glacial till. The risk of liquefaction at this site is considered low for the design level earthquake. Infiltration Characteristics We understand stormwater control will be provided by infiltration facilities, if feasible. Assessment of infiltration was completed per the 2016 King County Surface Water Design Manual (and 2014 DOE Stormwater Management Manual for Western Washington. Two small-scale Pilot Infiltration Tests (PIT) were attempted on the site. However, shallow seepage into the PIT-1 test hole prevented accurate measurements. Seepage was not observed in the PIT-2 test site. Results of the infiltration test is provided in Table 3. Geotechnical Engineering Report SSGC Sunset Highlands Mixed-Use Development NE Sunset Boulevard Renton, Washington SSGC Project No. 18003 February 12, 2018 9 Table 3. Infiltration Rates Test Site and Depth (ft) Soil Type Field Infiltration Rate (in/hr) Corrected Infiltration Rate (in/hr) Correction Factors* (Fg/Ft/Fp) PIT-1, 2 ft Alluvium N/A N/A (0.7/0.5/0.8) PIT-2, 2 ft Alluvium 1.5 0.42 (0.7/0.5/0.8) *Correction Factors from the 2016 King County Surface Design Manual. Calculated and corrected infiltration rates are considered appropriate for the upper soil tested. Gradation tests completed on samples from two of the test pits suggests the upper sand soils are similar across the site and would provide similar infiltration rates. We recommend a preliminary long-term design rate of 0.4 inches per hour (in/hr) is used for design of infiltration facilities located in soils above dense unweathered till. Other correction factors should be applied to the above recommended long-term rate, as required for the type of infiltration system selected. It should be noted that infiltrated water will migrate down to the denser till and then flow laterally downslope towards the wetland (to the south). Shallow perched groundwater was observed in all of the test pits. Infiltration facilities such as trenches or ponds are not considered feasible on this site. Bioswales, pervious pavements, or other shallow dispersion systems could be considered in the upper sand soils, if allowed by the City. Cation Exchange Capacity (CEC) and organic content test were completed on a sample from the base of the PIT-2 site. Test results are summarized in the table below. Table 4. CEC and Organic Content Results Test Location, Sample Number, and Depth CEC Results (milliequivalents) CEC Required* (milliequivalents) Organic Content Results (%) Organic Content Required* (%) PIT-2, S-1, 2 ft 12.1 ≥ 5 4.11 ≥1.0 *Per the 2016 DOE Stormwater Management Manual for Western Washington Organic content and CEC test results satisfy King County and DOE requirements. Geotechnical Engineering Report SSGC Sunset Highlands Mixed-Use Development NE Sunset Boulevard Renton, Washington SSGC Project No. 18003 February 12, 2018 10 Conventional Pavement Sections Subgrades for conventional pavement areas should be prepared as described in the “Subgrade Preparation” section of this report. Subgrades below pavement sections should be graded or crowned to promote drainage and not allow for ponding of water beneath the section. If drainage is not provided and ponding occurs, the subgrade soils could become saturated, lose strength, and result in premature distress to the pavement. In addition, the pavement surfacing should also be graded to promote drainage and reduce the potential for ponding of water on the pavement surface. Minimum recommended pavement sections for conventional pavements are presented in Table 5. Pavement sections in public right-of-ways should conform to City of Edgewood requirements for the road designation. Table 5. Preliminary Pavement Sections Traffic Area Minimum Recommended Pavement Section Thickness (inches) Asphalt Concrete Surface1 Portland Cement Concrete2 Aggregate Base Course3,4 Subbase Aggregate5 Access Drive 3 - 6 12 Parking 2 - 4 12 1 1/2 –inch nominal aggregate hot-mix asphalt (HMA) per WSDOT 9-03.8(1) 2 A 28 day minimum compressive strength of 4,000 psi and an allowable flexural strength of at least 250 psi 3 Crushed Surfacing Base Course per WSDOT 9-03.9(3) 4Although not required for structural support under concrete pavements, a minimum four-inch thick base course layer is recommended to help reduce potentials for slab curl, shrinkage cracking, and subgrade “pumping” through joints 5 Native granular soils compacted to 95% of the ASTM D1557 test method, or Gravel Borrow per WSDOT 9-03.14(1) or Crushed Surfacing Base Course WSDOT 9-03.9(3) Conventional Pavement Maintenance The performance and lifespan of pavements can be significantly impacted by future maintenance. The above pavement sections represent minimum recommended thicknesses and, as such, periodic maintenance should be completed. Proper maintenance will slow the rate of pavement deterioration, and will improve pavement performance and life. Preventative maintenance consists of both localized maintenance (crack and joint sealing and patching) and global maintenance (surface sealing). Added maintenance measures should be anticipated over the lifetime of the pavement section if any existing fill or topsoil is left in-place beneath pavement sections. Geotechnical Engineering Report SSGC Sunset Highlands Mixed-Use Development NE Sunset Boulevard Renton, Washington SSGC Project No. 18003 February 12, 2018 11 Porous Pavements Porous (pervious) asphalt pavements could be considered to facilitate stormwater control provided subgrades consist of the upper sand (alluvium) soil. We recommend pervious pavements are only considered in light duty traffic areas. Porous pavements are not recommended in heavy duty traffic areas, or areas directly underlain by dense glacial till. Infiltration characteristics of site soils are discussed in the “Infiltration Characteristics” section of this report. Porous pavement sections typically use a storage bed of free–draining imported granular material under the surface pavement. The thickness of the storage layer should be sized for the amount of stormwater to be stored and infiltration characteristics of the soil, and can range from about 6 inches to over 18 inches. Storage bed material should conform to the gradation criteria presented in Section 9- 03.9(2) “Permeable Ballast” of the WSDOT Specifications for Road, Bridge, and Municipal Construction (Publication M 41-10). A thin (approximately 2-inch) choker course layer of material meeting criteria of Section 9-03.12(4) of the WSDOT manual should be placed above and below the storage bed material. A geotextile separation fabric could be used in lieu of the lower choker course material. Gradations of the storage bed and choker course layers are presented in Table 6. Table 6. Storage Bed and Choker Course Materials US Standard Sieve Size Total Percent Passing Sieve Storage Bed WSDOT 9-03.9(2) Choker Course WSDOT 9-03.12(4) 2 ½” 99-100 2” 65-100 1 ½” 1” 100 3/4” 40-80 80-100 3/8” 0-40 #4 5 0-4 #200 0-1.5 0-2 We recommend the pervious asphalt layer have a thickness of at least 3-inches. Geotechnical Engineering Report SSGC Sunset Highlands Mixed-Use Development NE Sunset Boulevard Renton, Washington SSGC Project No. 18003 February 12, 2018 12 The lower choker course layer and initial lift of storage bed material should be compacted with non-vibratory rollers to limit densification of subgrade soils. The upper storage bed and the choker course layer should be compacted to a firm and unyielding condition achieving a compaction level of approximately 92 percent of the maximum dry density per the ASTM D-1557 test method. Porous Pavement Maintenance The performance and lifespan of porous pavements is highly dependent on maintenance. Maintenance of porous pavements will be necessary to retain the drainage characteristics of the asphalt. Regular cleaning of the surface will be required for the porous pavement. Typically, this is completed using vacuum equipment to remove fine sediment and vegetation that will collect on the asphalt surface. It is not practical at this time to estimate the amount of cleaning required for this site as it will be dependent on the amount of vehicle traffic, surrounding vegetation, and cleanliness of adjacent road surfaces leading into the site. However, at least annual cleaning of the surface via vacuuming should be completed with more frequent cleaning if excessive dirt or vegetation is observed collecting on the pavement surface during particular times of the year. Regular sweeping of the asphalt surface could help in maintaining a cleaner surface. Porous pavements typically have slightly coarser average aggregate size (fewer fines) to achi eve the porosity of the asphalt. As such, they have the tendency to ravel and not wear as well as conventional asphalt sections, particularly in high traffic areas and in areas where repetitive short radius turns occur. Regular maintenance will improve the lifespan of the porous pavement section. REPORT CONDITIONS This report has been prepared for the exclusive use of ADF Properties and their agents for specific application to the project discussed, and has been prepared in accordance with generally accepted geotechnical engineering practices in the area. No warranties, either express or i mplied, are intended or made. The analysis and recommendations presented in this report are based on observed soil conditions and test results at the indicated locations, and from other geologic information discussed. This report does not reflect variations that may occur across the site, or due to the modifying effects of construction or weather. The nature and extent of such variations may not become evident until during or after construction. If variations appear, we should be immediately notified so that further evaluation and supplemental recommendations can be provided. This report was prepared for the planned type of development of the site as discussed herein. It is not valid for third party entities or alternate types of development on the site without the express written consent of SSGC. If development plans change we should be notified to review those changes and modify our recommendations as necessary. N South Sound Geotechnical Consulting P.O. Box 39500 Lakewood, WA 98496 (253) 973-0515 Figure 1 – Exploration Plan Sunset Highlands Mixed-Use Renton, WA SSGC Project #18003 Approximate Test Pit Location PIT - 1 TP - 1 PIT-1 PIT - 1 Approximate Infiltration Test Location Scale: NTS Base map from drawing “Profile Exhibit”, by AHBL, Inc) TP-2 Legend TP-4 TP-1 TP-3 TP-1 TP-1 TP-1 PIT-2 TP-5 TP-1 Geotechnical Engineering Report SSGC Sunset Highlands Mixed-Use Development NE Sunset Boulevard Renton, Washington SSGC Project No. 18003 February 12, 2018 A-1 Appendix A Field Exploration Procedures and Test Pit Logs Geotechnical Engineering Report SSGC Sunset Highlands Mixed-Use Development NE Sunset Boulevard Renton, Washington SSGC Project No. 18003 February 12, 2018 Field Exploration Procedures8 Our field exploration for this project included five test pits and one infiltration test completed on January 24, 2018. The approximate locations of the explorations are shown on Figure 1, Exploration Plan. The exploration locations were determined by pacing from site features. Ground surface elevations referenced on the logs were inferred from Google Satellite imagery. Test pit locations and elevations should be considered accurate only to the degree implied by the means and methods used. A private excavation company subcontracted to SSGC dug the test pits. Soil samples were collected and stored in moisture tight containers for further assessment and laboratory testing. Explorations were backfilled with excavated soils and tamped when completed. Please note that backfill in the explorations will likely settle with time. Backfill material located in building areas should be re-excavated and recompacted, or replaced with structural fill. The following logs indicate the observed lithology of soils and other materials observed in the explorations at the time of excavation. Where a soil contact was observed to be gradational, our log indicates the average contact depth. Our logs also indicate the approximate depth to groundwater (where observed at the time of excavation), along with sample numbers and approximate sample depths. Soil descriptions on the logs are based on the Unified Soil Classification System. Project: Sunset Apartments SSGC Job # 18003 TEST PIT LOGS PAGE 1 OF 2 Location: Auburn, WA TEST PIT LOGS FIGURE A-1 South Sound Geotechnical Consulting TP-1 TO TP-5 Logged by: THR Test Pit TP-1 Depth (feet) Material Description 0 – 1 1 – 3.5 3.5 - 5.5 Fill/Topsoil: Silt, sand, and gravel over about 3 inches of topsoil. SAND with some silt: Loose to medium dense, moist to wet, reddish brown. (Sample S-1 @ 2 feet) Silty SAND with gravel: Medium dense to dense, moist, gray. (Sandy Glacial Till) Test pit completed at approximately 5.5 feet on 1/24/18. Seepage observed at about 3.5 feet at time of excavation. Approximate surface elevation: 398 feet Test Pit TP-2 Depth (feet) Material Description 0 – 1 1 – 4 4 - 6 Topsoil: Silty sand with organics: Loose, moist, dark brown. SAND with some silt: Loose to medium dense, moist to wet, reddish brown. SAND with silt and gravel: Medium dense to dense, moist, gray. (Sandy Glacial Till) Test pit completed at approximately 6 feet on 1/24/18. Seepage observed at about 3.5 feet at time of excavation. Approximate surface elevation: 396 feet Test Pit TP-3 Depth (feet) Material Description 0 – 1.5 1.5 – 2.5 2.5 - 5 Fill: Silt, sand, and gravel with some organics: Loose, moist, dark brown. SAND with some silt: Loose to medium dense, moist to wet, reddish brown. SAND with silt and gravel: Medium dense to dense, moist, gray. (Sandy Glacial Till) Test pit completed at approximately 5 feet on 1/24/18. Seepage observed at about 2.5 feet at time of excavation. Approximate surface elevation: 396 feet Project: Sunset Apartments SSGC Job # 18003 TEST PIT LOGS PAGE 2 OF 2 Location: Auburn, WA TEST PIT LOGS FIGURE A-1 South Sound Geotechnical Consulting TP-1 TO TP-5 Logged by: THR Test Pit TP-4 Depth (feet) Material Description 0 – 1.5 1.5 – 3.5 3.5 - 6 Fill: Silt, sand, and gravel with some organics: Loose, moist, dark brown. Silty SAND with some gravel and occasional cobble: Medium dense, moist, grayish brown. SAND with silt and gravel: Medium dense to dense, moist, gray. (Sandy Glacial Till) Test pit completed at approximately 6 feet on 1/24/18. Seepage observed at about 3 feet at time of excavation. Approximate surface elevation: 397 feet Test Pit TP-5 Depth (feet) Material Description 0 – 1 1 – 2.5 2.5 - 5 Fill: Silt, sand, and gravel with some organics: Loose, moist, dark brown. Silty SAND with some gravel and occasional cobble: Medium dense, moist, grayish brown. SAND with silt and gravel: Medium dense to dense, moist, gray. (Sandy Glacial Till) Test pit completed at approximately 5 feet on 1/24/18. Seepage observed at about 2.5 feet at time of excavation. Approximate surface elevation: 398 feet Geotechnical Engineering Report SSGC South Lawrence Avenue Self Storage South Lawrence Avenue at South 19th Street Tacoma, Washington SSGC Project No. 17051 July 18, 2017 B-1 Appendix B Laboratory Testing and Results Geotechnical Engineering Report SSGC Sunset Highlands Mixed-Use Development NE Sunset Boulevard Renton, Washington SSGC Project No. 18003 February 12, 2018 B-1 Laboratory Testing Select soil samples were tested for organic content and cation exchange capacity (CEC) by Northwest Agricultural Consultants of Kennewick, Washington. Gradation tests were completed by Construction Testing Laboratories (CTL) of Puyallup, Washington. Results of the laboratory testing are included in this appendix. Report shall not be reproduced except in full without the written approval of the Laboratory. Report pertains only to the material tested.Tested By: B. Rowden Checked By: C. Pedersen Particle Size Distribution Report ASTM C-117,C136 PERCENT FINER0 10 20 30 40 50 60 70 80 90 100 GRAIN SIZE - mm. 0.0010.010.1110100 % +3"Coarse % Gravel Fine Coarse Medium % Sand Fine Silt % Fines Clay 0.0 0.0 3.8 5.1 49.8 31.1 10.26 in.3 in.2 in.1½ in.1 in.¾ in.½ in.3/8 in.#4#10#20#30#40#60#100#140#200SIEVE PERCENT SPEC.*PASS? SIZE FINER PERCENT (X=NO) Material Description Atterberg Limits Classification Remarks Source of Sample: TP-5 Sample Number: 18-098 Date: Client: Project: Project No:Figure Grab Sample, S-1 Sampled at 2'3/4" 1/2" 3/8" #4 #8 #16 #30 #50 #100 #200 100.0 99.5 98.4 96.2 92.2 84.6 61.0 24.0 13.9 10.2 Report: #02 Sampled by: Client South Sound Geotechnical Sunset Apartments (JO #18003) 7073 PL=LL=PI= USCS=AASHTO= *(no specification provided) 01-31-18 Construction Testing Laboratories 400 Valley Ave. NE, Suite #102 Puyallup WA, 98372 Tel. (253) 383-8778 Report shall not be reproduced except in full without the written approval of the Laboratory. Report pertains only to the material tested.Tested By: B. Rowden Checked By: C. Pedersen Particle Size Distribution Report ASTM C-117,C136 PERCENT FINER0 10 20 30 40 50 60 70 80 90 100 GRAIN SIZE - mm. 0.0010.010.1110100 % +3"Coarse % Gravel Fine Coarse Medium % Sand Fine Silt % Fines Clay 0.0 0.0 0.6 2.6 47.8 39.5 9.56 in.3 in.2 in.1½ in.1 in.¾ in.½ in.3/8 in.#4#10#20#30#40#60#100#140#200SIEVE PERCENT SPEC.*PASS? SIZE FINER PERCENT (X=NO) Material Description Atterberg Limits Classification Remarks Source of Sample: TP-1 Sample Number: 18-097 Date: Client: Project: Project No:Figure Grab Sample, S-1 Sampled at 2'3/8" #4 #8 #16 #30 #50 #100 #200 100.0 99.4 97.6 91.6 70.8 28.0 13.0 9.5 Report: #01 Sampled by: Client South Sound Geotechnical Sunset Apartments (JO #18003) 7073 PL=LL=PI= USCS=AASHTO= *(no specification provided) 01-31-18 Construction Testing Laboratories 400 Valley Ave. NE, Suite #102 Puyallup WA, 98372 Tel. (253) 383-8778 2545 W Falls Avenue Kennewick, WA 99336 509.783.7450 www.nwag.com lab@nwag.com Sample ID Organic Matter Cation Exchange Capacity IT-2, S-1 4.11% 12.1 meq/100g Method ASTM D2974 EPA 9081 South Sound Geotechnical Consulting PO Box 39500 Lakewood, WA 98496 Report: 43567-1 Date: February 5, 2018 Project No: 18003 Project Name: Sunset Highlands UNIFIED SOIL CLASSIFICATION SYSTEM Criteria for Assigning Group Symbols and Group Names Using Laboratory TestsA Soil Classification Group Symbol Group NameB Coarse Grained Soils More than 50% retained on No. 200 sieve Gravels More than 50% of coarse fraction retained on No. 4 sieve Clean Gravels Less than 5% finesC Cu  4 and 1  Cc  3E GW Well-graded gravelF Cu  4 and/or 1  Cc  3E GP Poorly graded gravelF Gravels with Fines More than 12% finesC Fines classify as ML or MH GM Silty gravelF,G, H Fines classify as CL or CH GC Clayey gravelF,G,H Sands 50% or more of coarse fraction passes No. 4 sieve Clean Sands Less than 5% finesD Cu  6 and 1  Cc  3E SW Well-graded sandI Cu  6 and/or 1  Cc  3E SP Poorly graded sandI Sands with Fines More than 12% finesD Fines classify as ML or MH SM Silty sandG,H,I Fines Classify as CL or CH SC Clayey sandG,H,I Fine-Grained Soils 50% or more passes the No. 200 sieve Silts and Clays Liquid limit less than 50 inorganic PI  7 and plots on or above “A” lineJ CL Lean clayK,L,M PI  4 or plots below “A” lineJ ML SiltK,L,M organic Liquid limit - oven dried  0.75 OL Organic clayK,L,M,N Liquid limit - not dried Organic siltK,L,M,O Silts and Clays Liquid limit 50 or more inorganic PI plots on or above “A” line CH Fat clayK,L,M PI plots below “A” line MH Elastic SiltK,L,M organic Liquid limit - oven dried  0.75 OH Organic clayK,L,M,P Liquid limit - not dried Organic siltK,L,M,Q Highly organic soils Primarily organic matter, dark in color, and organic odor PT Peat A Based on the material passing the 3-in. (75-mm) sieve B If field sample contained cobbles or boulders, or both, add “with cobbles or boulders, or both” to group name. C Gravels with 5 to 12% fines require dual symbols: GW -GM well-graded gravel with silt, GW -GC well-graded gravel with clay, GP-GM poorly graded gravel with silt, GP-GC poorly graded gravel with clay. D Sands with 5 to 12% fines require dual symbols: SW -SM well-graded sand with silt, SW -SC well-graded sand with clay, SP-SM poorly graded sand with silt, SP-SC poorly graded sand with clay E Cu = D60/D10 Cc = 6010 2 30 DxD )(D F If soil contains  15% sand, add “with sand” to group name. G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM. HIf fines are organic, add “with organic fines” to group name. I If soil contains  15% gravel, add “with gravel” to group name. J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay. K If soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel,” whichever is predominant. L If soil contains  30% plus No. 200 predominantly sand, add “sandy” to group name. M If soil contains  30% plus No. 200, predominantly gravel, add “gravelly” to group name. N PI  4 and plots on or above “A” line. O PI  4 or plots below “A” line. P PI plots on or above “A” line. Q PI plots below “A” line. Preliminary Technical Information Report Sunset Highlands Mixed Use 2190210.10 Appendix E Non-Structural BMPs A-1 .................... Required Best Management Practices (BMPs) for all Properties with Commercial Activities A-8 .................... Storage or Solid and Food Wastes (Including Cooking Grease) A-45 .................. Maintenance of Public and Private Utility Corridors and Facilities Stormwater Pollution Prevention Manual • King County 27 A-1 Required Best Management Practices for all Properties with Commercial Activities The following Best Management Practices (BMPs) are required for all commercial, industrial, agricultural, public, or residential properties with commercial activities in unincorporated King County. Best Management Practices (BMPs) are required by King County Code 9.12. If the BMPs included here are not enough to prevent contamination of stormwater, you will be required to take additional measures. Required BMPs: Clean and Maintain Storm Drainage System • Evaluate the condition of the catch basin by checking the amount of sediment in the bottom of the sump. Catch basins must be cleaned out when the solids, trash, and debris in the sump reaches one–half of the depth between the bottom of the sump and the bottom of the lowest inflow or outflow pipe connected to the catch basin or is at least 6 inches below this point. • Hire a professional drainage contractor to inspect and maintain your system or clean the system yourself. If there is sediment or other debris in the drainage pipes, then a professional contractor must be hired to flush or jet out the pipes. • Small amounts of floating oil can be soaked up with oil absorbent pads, bagged and disposed of as solid waste. • Up to one cubic yard of nonhazardous solid material may be disposed of as solid waste in your regular garbage. If you exceed this threshold hire a professional drainage contractor. All of the solids and stagnant water collected from catch basin sumps must be disposed of properly. None of the sump contents can be flushed into the catch basin outflow pipe. Depending on the nature of the pollutants in the sump, and the associated types of activities taking place on the site, the sump contents may need to be handled as contaminated waste. Contractors who perform catch basin clean–out services are required to follow appropriate disposal requirements. • Clean and maintain catch basins annually. Sites with activities generating a lot of sediments and other debris will have to inspect and clean out their catch basins more often. Frequent sweeping of paved parking and storage areas will save time and money in maintaining the drainage system. • Other components of drainage systems such as ponds, tanks, and bioswales must also be maintained. If this maintenance is beyond your ability, contractors are available to complete this work. Label All Storm Drain Inlets on Your Property • Stencil or apply storm drain markers adjacent to storm drains to help prevent the improper disposal of pollutants. If the storm drain grate is stamped with warnings against polluting, then additional marking may not be required if there is no evidence of pollutants being dumped or washed into the storm drain. Stormwater Pollution Prevention Manual • King County28 Eliminate Illicit Connections to the Storm Drainage System • Connections to the storm drainage system that convey substances other than stormwater are prohibited. Examples are connections from internal floor drains, HVAC systems, industrial processes, sinks, and toilets. • Illicit connections must be immediately removed, permanently plugged or re–plumbed. • The discharge must be re–plumbed so that it goes to the sanitary sewer, a septic system, an on–site treatment system, or a holding tank for off–site disposal. There are restrictions on what can be disposed of to the sanitary sewer and septic systems. You may be required to do additional investigation to determine where all stormwater and non–stormwater discharges go. This may include smoke, dye, and chemical testing or closed circuit television inspection. Additional Information: • Drainage System Maintenance Contractors Information Sheet • For stencils and instructions or to determine if you have an illicit connection, contact King County Stormwater Services at 206–477–4811 or kingcounty.gov/stormwater. Stormwater Pollution Prevention Manual • King County 35 A-8 Storage or Solid and Food Wastes (Including Cooking Grease) This refers to garbage dumpsters and outdoor waste containers such as cooking oil/grease receptacles. Best Management Practices (BMPs) are required by King County Code 9.12. If the BMPs included here are not enough to prevent contamination of stormwater, you will be required to take additional measures. Required BMPs: • Store wastes in leak–proof containers with solid lids. • Keep dumpsters closed except when adding waste. • Used cooking oil/grease containers should be labeled with their contents. • Clean up any spills immediately using dry methods. Grease cannot be left on the ground. • Have spill cleanup materials nearby. • Use a lid or cover when transporting cooking oil/grease containers from kitchens to outside grease containers. • Ensure that drip pans or absorbent materials are used whenever grease containers are emptied by vacuum trucks or other means. • Dispose of collected cooking oil/grease as garbage if it is not being recycled. Do not dispose of fats, oils or grease (FOG) into the sanitary sewer or septic system. Required Routine Maintenance: • Keep the area around the grease container clean and free of debris. • Check storage containers frequently for leaks and to ensure that lids are on securely. • Replace leaking or damaged containers. Contact waste hauler for replacements. • Sweep and clean the storage area as needed if it is paved. Do not hose down waste storage areas. • When cleaning or rinsing waste containers, dispose of all wastewater into a sanitary sewer. If no sewer is available, store in a holding tank, dead end sump, or truck o site to an approved disposal location. Additional Information: • Disposal Information Sheet For more information or assistance contact the King County Stormwater Services at 206–477–4811 and visit kingcounty.gov/stormwater. Stormwater Pollution Prevention Manual • King County 77 A-45 Maintenance of Public and Private Utility Corridors and Facilities This covers maintenance activities associated with the transmission and distribution of public and private utilities such as petroleum products, natural gas, water, sewage, and electrical power. This includes the maintenance of underground utility vaults, pump stations, and similar facilities. Best Management Practices (BMPs) are required by King County Code 9.12. If the BMPs included here are not enough to prevent contamination of stormwater, you will be required to take additional measures. Required BMPs: • Minimize the amount of herbicides and other pesticides used to maintain access roads and facilities. • Stabilize access roads or areas of bare ground with gravel, crushed rock, or another method to prevent erosion. Use and manage vegetation to minimize bare ground/soils that may be susceptible to erosion. • Provide stormwater drainage for roads and maintenance areas. Grade roads with a crown or slope to minimize the potential for erosion from runo. Provide ditches, swales, and culverts to convey stormwater runo. • Keep ditches and culverts clear to reduce the possibility of the drainage becoming plugged or blocked, causing overows and erosion. • Check utility vaults or other underground structures for oil prior to pumping out any collected water. Contaminated water must be collected for proper disposal. Small amounts of oil may be captured with absorbent material. Never discharge contaminated water, including high or low pH, to storm drainage facilities or surface waters. • When removing water and/or sediment from electrical transformer vaults, determine from records or testing if the transformers contain PCBs. • Clean up any debris or spilled material immediately after completing maintenance and repair activities. Additional Information: • Landscaping Activities and Vegetation Management – Activity Sheet A-26 • Erosion and Sediment Control Standards – King County Surface Water Design Manual, Appendix D • Work in public road right of ways requires permission from King County Utility Inspection Program (206) 296–8122. Preliminary Technical Information Report Sunset Highlands Mixed Use 2190210.10 Appendix F Critical Areas Report By Sewall Wetland Consulting, Inc., dated March 22, 2018 Note: this report is preliminary and as such has an outdated site plan with similar encroachments and surfacing proposed March 22, 2018 ADF Properties, LLC 15007 Woodinville Redmond Road, Suite A Woodinville, Washington 98072 RE: Sunset Highlands Critical Areas Report – Parcel # 0323059093 SWC Job #18-108 This report describes our observations of any jurisdictional wetlands, streams and buffers on or within 200’ of Parcel # 0323059093, located off NE Sunset Way, in the City of Renton, Washington (the “site”). Above: King County iMap of site Specifically, the site is a 0.81 acre irregular shaped parcel located in the SW ¼ of Section 3, Township 23 North, Range 5 East of the Willamette meridian in King County Washington. Sewall Wetland Consulting, Inc. Po Box 880 Phone: 253-859-0515 Fall City, WA 98024 ADF/#18-108 Sewall Wetland Consulting, Inc. March 22, 2018 Page 2 METHODOLOGY Ed Sewall of Sewall Wetland Consulting, Inc. inspected the site on February 20, 2018. The site was previously delineated by Sewall Wetland Consulting on May 17, 2007. The site was reviewed using methodology described in the Washington State Wetlands Identification Manual (WADOE, March 1997). This is the methodology currently recognized by the City of Renton and the State of Washington for wetland determinations and delineations. The site was also inspected using the methodology described in the Corps of Engineers Wetlands Delineation Manual (Environmental Laboratory, 1987), and the Western Mountains, Valleys and Coast region Supplement (Version 2.0) dated June 24, 2010, as required by the US Army Corps of Engineers. Soil colors were identified using the 1990 Edited and Revised Edition of the Munsell Soil Color Charts (Kollmorgen Instruments Corp. 1990). ] ADF/#18-108 Sewall Wetland Consulting, Inc. March 22, 2018 Page 3 Soil colors were identified using the 1990 Edited and Revised Edition of the Munsell Soil Color Charts (Kollmorgen Instruments Corp. 1990). OBSERVATIONS Existing Site Documentation. Prior to visiting the site, a review of several natural resource inventory maps was conducted. Resources reviewed included the National Wetland Inventory Map, WADNR Fpars, and the NRCS Soil Survey online mapping and Data. Soil Survey According to the King County Soil Survey, the soils onsite are completely comprised of the Ragnar Indianola soil association, sloping (RDC). Ragnar soils are not considered to be hydric (wetland) soils, according to the publication Hydric Soils of the United States (USDA NTCHS Pub No.1491, 1991). Above: USDA Soil Survey Map of the site National Wetlands Inventory (NWI) According to the NWI map for the site there are no wetlands on or near the site. ADF/#18-108 Sewall Wetland Consulting, Inc. March 22, 2018 Page 4 Above: National Wetlands Inventory Map of the site. WADNR Fpars Stream Mapping The Washington Department of Natural Resources Fpars stream type mapping website depicts no streams on or near the site. ADF/#18-108 Sewall Wetland Consulting, Inc. March 22, 2018 Page 5 Above: WADNR Fpars stream mapping City of Renton Water Resource Map The US Fish and Wildlife online wetland mapper and the Department of Natural Resources FPARS maps do not show any wetlands or streams located onsite. However, there is a non-fish bearing portion of Honey Dew Creek mapped offsite to the northeast. According to the City of Renton flood hazard and wetlands maps, there are no known flood hazards or wetlands within 100-feet of the site (Figures 4-3-050Q2 and 4-3-050Q5). The City of Renton Water Class Map in RMC 4-3-050Q4 shows Honey Dew Creek extending across NE Sunset Boulevard, at which point it becomes a Class 4 stream, and then entering the site. City of Renton Water Class Map ADF/#18-108 Sewall Wetland Consulting, Inc. March 22, 2018 Page 6 Sewall Wetland Consulting, Critical Areas Study Sunset Property November 7, 2007 Our company prepared a critical areas study and restoration plan for the stream buffer in November of 2007. At that time, a Type 4 stream was found along the south edge of the site. This is a ditched upper portion of Honey Dew Creek. At that time this stream had a 35’ buffer which was reduced to 25’ with enhancement and a split rail fence. The mitigation area was installed and initially monitored until transient use of the site destroyed and eliminated much of the plantings in the area. Above: Previously approved mitigation plan sections showing stream and 25’ buffer. Field observations Uplands The site is generally devoid of vegetation as the blackberry and giant knotweed thicket that was a transient encampment has been kept mowed down. The only existing vegetation is along the property boundaries and along the stream at the southern end of the property. Dominant vegetation within the vegetated uplands included red alder ADF/#18-108 Sewall Wetland Consulting, Inc. March 22, 2018 Page 7 (Alnus rubra), Japanese knotweed (Polyganum cuspidatum), and Himalayan blackberry (Rubus armeniacus). Soils within the uplands generally revealed a compact 16-inch gravelly sandy loam layer with a color of 10YR 3/3. Soils within the uplands were dry at the time of our May 17th site visit. Wetlands No areas meeting wetland criteria are found on the site. Streams A ditched stream, identified as Stream A, flows eastward across the southeast property corner of the site between two culverts. Stream A was flagged with white with blue dot boundary flagging labeled A1 though A8 on the north ordinary high water mark (OHWM) and AA1 through AA8 on the south OHWM. The onsite section of the stream is assumed to be part of the mapped Honey Dew Creek, as previously described. The City of Renton Aquifer protection map (RMC Figure 4-3-050Q1) shows that this stream flows subsurface within a pipe from the north side of NE Sunset Boulevard onto the site, surfaces across the site, and then exits via a second culvert which discharges at the west side of Duvall Avenue NE, approximately 1000-feet to the east of the site. The banks of the ditch and associated stream buffers contain forested and scrub-shrub vegetative communities. Dominant vegetation adjacent to the stream includes red alder (Alnus rubra), Himalayan blackberry (Rubus armeniacus), and giant knotweed (Polyganum cupsodatum). Stream A has an average channel with of approximately 2 -feet and an average depth of approximately 12-inches. At the time of site visit, the channel contained flowing water approximately 8-inches deep. The stream bed was unconsolidated and comprised of a mixture of sand and gravel. Due to the long distances in which this stream is located within subsurface pipes, the segmented portion of stream and stream buffer located onsite provide very little hydrologic or ecologic function. The site ADF/#18-108 Sewall Wetland Consulting, Inc. March 22, 2018 Page 8 is totally surrounded by urban development, and no evidence of wildlife presence was observed onsite during our field visit. Stream A would be considered a Type Ns stream, due to lack of fish use and season flow. Typically, Type Ns streams have a 50’ buffer as well as a 15’ building setback for structures. Proposed Project The proposed project is the construction of a multifamily apartment complex. Due to the diagonal configuration of the site forcing struct ures on an angle across the site, as well as the fact the buffer was a previously fenced 25’ area and now includes a degraded area, a reduced buffer is proposed. Under RMC 44-3-050-I.1, Type Ns streams can have their buffer reduced to 40’ if it meets the following criteria; a. Criteria for Reduction of Degraded Stream Buffer Width with Enhancement: A reduced buffer will be approved in a degraded stream buffer only if: i. It will provide an overall improvement in water quality; and Response: Removal of existing trash and use by transients will greatly improve water quality. Planting with native trees and shrubs will help filter any runoff and improve stream function. ii. It will provide an overall enhancement to fish, wildlife, or their habitat; and Response: The reduced and enhanced buffer will improve water quality and shading of the stream, which will improve overall functions of the stream. Removal of transients and trash will greatly improve water quality and create a safe habitat area that doesn’t exist today. ADF/#18-108 Sewall Wetland Consulting, Inc. March 22, 2018 Page 9 iii. It will provide a net improvement in drainage and/or stormwater detention capabilities; and Response: The proposed reduced buffer and site stormwater facilities will improve stormwater functions of the site. iv. It will not be materially detrimental to any other property or the City as a whole; and Response: The proposed reduced buffer will not be detrimental to any property and will be an improvement over current heavily degraded conditions. v. It will provide all exposed areas with stabilized native vegetation, as appropriate; and Response: The proposed enhancement of the reduced buffer will stabilize the buffer with native vegetation. vi. The request is not made in conjunction with buffer reduction, an vii. It will provide, as part of the buffer reduction request, buffer enhancement plan prepared by a qualified professional and fund a review o f the plan by the City’s consultant. The plan shall assess habitat, water quality, stormwater detention, groundwater recharge, shoreline protection, and erosion protection functions of the buffer; assess the effects of the proposed modification on those fu nctions; and address the six (6) criteria listed above. Response: A stream buffer enhancement plan will be provided to the City as required after this reduction request is approved. The impacted buffer area for the structure will be averaged as shown on the plan. ADF/#18-108 Sewall Wetland Consulting, Inc. March 22, 2018 Page 10 If you have any questions in regards to this report or need additional information, please feel free to contact me at (253) 859-0515 or at esewall@sewallwc.com . Sincerely, Sewall Wetland Consulting, Inc. Ed Sewall Senior Wetlands Ecologist PWS #212 ADF/#18-108 Sewall Wetland Consulting, Inc. March 22, 2018 Page 11 REFERENCES Cowardin, L., V. Carter, F. Golet, and E. LaRoe. 1979. Classification of Wetlands and Deepwater Habitats of the United States. U.S. Fish and Wildlife Service, FWS/OBS-79-31, Washington, D. C. Environmental Laboratory. 1987. Corps of Engineers Wetlands Delineation Manual, Technical Report Y-87-1. U. S. Army Corps of Engineers Waterways Experiment Station, Vicksburg, Mississippi. Muller-Dombois, D. and H. Ellenberg. 1974. Aims and Methods of Vegetation Ecology. John Wiley & Sons, Inc. New York, New York. Munsell Color. 1988. Munsell Soil Color Charts. Kollmorgen Instruments Corp., Baltimore, Maryland. National Technical Committee for Hydric Soils. 1991. Hydric Soils of the United States. USDA Misc. Publ. No. 1491. Reed, P., Jr. 1988. National List of Plant Species that Occur in Wetlands: Northwest (Region 9). 1988. U. S. Fish and Wildlife Service, Inland Freshwater Ecology Section, St. Petersburg, Florida. Reed, P.B. Jr. 1993. 1993 Supplement to the list of plant species that occur in wetlands: Northwest (Region 9). USFWS supplement to Biol. Rpt. 88(26.9) May 1988. City of Renton Code USDA NRCS & National Technical Committee for Hydric Soils, September 1995. Field Indicators of Hydric Soils in the United States - Version 2.1 ADF/#18-108 Sewall Wetland Consulting, Inc. March 22, 2018 Page 12 Above and below: stream as it passes through the site. ADF/#18-108 Sewall Wetland Consulting, Inc. March 22, 2018 Page 13 Above and below: Looking north across the site. ADF/#18-108 Sewall Wetland Consulting, Inc. March 22, 2018 Page 14 Above and below: Stream as it passes off -site to the west 14"FIR 16"FIR 24"FIR 12"FIR 20"FIR 16"FIR 30"FIR 16"FIR 303.5 L F ROCK E R Y ROCK E R Y ROCKERY - - - - -5' HOG WIRE FENCE6' CY C L O N E F E N C E LS PV LS LS LS - SIDE W A L K 48" P o pl a r 24" CEDAR 30" Fir 18" MAPLE 30" FIR - > SB SIGNAL BOX SB TV N63°5 7' 2 7 " E 1423. 1 4' ( M ) 1423. 2 1' ( S T) 595.0 7' ( C ) 595.1 0' ( S T)S26°02 '33 "E 45 .00 ' NE SU N S E T B L V D N0° 00' 25"E174.68'N89° 37' 58"W 164.55'S0° 15' 59"W256.71'N63° 5 7' 2 7 " E 184.4 5' 400 397 398 399 401 400 396 397 398 399 400 396397398 3 9 9 STORM CHAMBER DETENTION SYSTEMSTORM CHAMBER DETENTION SYSTEM PERVIOUS PAVERS (TYP.) PERVIOUS PAVERS (TYP.) PERVIOUS ACCESS PATH 40' BUFFER BUFFER AVERAGING IMPACTED AREA 331 SF BUFFER AVERAGING REPLACEMENT AREA 331 SF 32' 31' Civil Engineers Structural Engineers Landscape Architects Community Planners Land Surveyors Neighbors SUNSET HIGHLANDS 2140679.10