The URL can be used to link to this page

APPROVED RESUB 4-BLD2022-1556+Storm_Drainage_Report+8.1.2024_10.30.31_AM+4415427BLD2022-1556 CC„O RESUB Aug 01 2024 CITY OF EDMONDS STORMWATER DEVELOPMENTS RVICES DEPARTMENT TECHNICAL INFORMATION REPORT 212T" STREET SITE REDEVELOPMENT EDMONDS, WASHINGTON Submitted by: CEKO, L.L.C. 2255 Squak Mountain Loop SW Issaquah, Washington 98027 CEKO PN: 22017.01 For: Glacier Environmental Services, Inc. 3415 1215t Street Southwest Lynnwood, Washington 98087 July 30, 2024 Prepared by: Christopher P. Kovac, P.E., LEED°AP Principal Engineer opHERA �� of WasySTORMWATER 0 ESU'S POST DEVELOPMENT: J <= 8.76 37219 e A�Ort+ I STER�� I NAL 'yG COMPLIES WITH APPLICABLE CITY STORMWATER CODE 10/09/2024 CC/CO, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com ccit-o TABLE OF CONTENTS 1.0 PROJECT OVERVIEW..................................................................................... 1-1 1.1 EXISTING CONDITIONS SUMMARY..........................................................1-1 1.2 PROPOSED SITE CONDITIONS.................................................................. 1-2 2.0 DETERMINATION OF APPLICABLE MINIMUM REQUIREMENTS ...................... 2-1 2.1 MINIMUM REQUIREMENT 1: PREPARATION OF STORMWATER SITE PLANS .................................................................................................................. 2-1 2.2 MINIMUM REQUIREMENT 2: STORMWATER POLLUTION PREVENTION PLAN .................................................................................................................. 2-1 2.3 MINIMUM REQUIREMENT 3: SOURCE CONTROL OF POLLUTION........... 2-1 2.4 MINIMUM REQUIREMENT 4: PRESERVATION OF NATURAL DRAINAGE SYSTEMS ANDOUTFALLS......................................................................................... 2-1 2.5 MINIMUM REQUIREMENT 5: ON -SITE STORMWATER MANAGEMENT.. 2-1 2.6 MINIMUM REQUIREMENT 6: RUNOFF TREATMENT ............................... 2-2 2.7 MINIMUM REQUIREMENT 7: FLOW CONTROL ....................................... 2-2 2.8 MINIMUM REQUIREMENT 8: WETLANDS PROTECTION ......................... 2-3 2.9 MINIMUM REQUIREMENT 9: OPERATION AND MAINTENANCE ............. 2-3 3.0 SITE ANALYSIS.............................................................................................. 3-1 3.1 OFF -SITE SUMMARY................................................................................. 3-1 3.2 DOWNSTREAM ANALYSES....................................................................... 3-1 3.3 UPSTREAM ANALYSIS............................................................................... 3-1 4.0 DEVELOPMENT LAYOUT............................................................................... 4-1 4.1 ON -SITE STORMWATER MANAGEMENT OVERVIEW ............................... 4-1 4.2 ON -SITE STORMWATER MANAGEMENT..................................................4-1 4.3 FLOW CONTROL.......................................................................................4-1 4.3.1 Existing Site Hydrology................................................................. 4-1 4.3.2 On -Site Stormwater Best Management Practices ....................... 4-2 4.3.3 Proposed Developed Site Hydrology...........................................4-3 4.4 WATER QUALITY SYSTEM......................................................................... 4-4 5.0 CONVEYANCE SYSTEM ANALYSIS AND DESIGN .............................................. 5-1 6.0 SPECIAL REPORTS AND STUDIES................................................................... 6-1 7.0 OTHER PERMITS...........................................................................................7-1 8.0 OPERATION AND MAINTENANCE MANUAL ................................................... 8-1 9.0 SECURITY DEVICE......................................................................................... 9-1 CAC EKOIProjectslActive122017.01-Glacier-Headquarters\EngineeringUlM2024-07-Stormwater-TI R.docx Cf/<q, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com ccit-o 10.0 REFERENCES...............................................................................................10-1 FIGURES Figure 1 Site Location Map Figure 2 Existing Conditions Figure 3 Flow Chart for Determining Requirements for Development Figure 4A USDA NRCS Soils Map Figure 4B USDA NRCS Soils Map Legend Figure 4C USDA NRCS Soils Map Legend Description Figure 4D USDA NRCS Soils Map Unit Description Figure 4E USDA NRCS Soils Map Unit Description (continued) Figure 5 FEMA Flood Hazard Map Figure 6 Downstream Drainage Map Figure 7 Proposed Conditions Figure 8 Site Drainage Areas Figure 9 Stormwater Management System Schematic Diagram APPENDICES Appendix A Site Areas Summary Appendix B Geotechnical Engineering Investigation Report Appendix C Stormwater Management System Modeling Report Appendix D Water Quality Facility Sizing Appendix E Conveyance Capacity Calculations Appendix F Operation and Maintenance Documentation CAC EKOIProjectslActive122017.01-Glacier-Headquarters\EngineeringUlM2024-07-Stormwater-TI R.docx 400/<9Z LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com ccit-o 1.0 PROJECT OVERVIEW CEKO, L.L.C. (CEKO) has prepared this Stormwater Technical Information Report (TIR) for the Glacier Environmental Services, Inc. (Glacier and/or the Client) 2121h Street Site Redevelopment project. The project work area consists of a portion of Snohomish County Parcel No. 00566900400600 at 7509 212th Street Southwest in Edmonds, Washington (herein referred to as the Property), an approximately 0.87-acre parcel of land developed with a single-family residence built in 1940 with several smaller outbuildings (Figures 1 and 2). The intent of the proposed redevelopment is to construct a new commercial facility to house Glacier's commercial operations. The Property is within the City of Edmonds limits, and the project will be subject to the jurisdictional requirements of the City of Edmonds and requirements of the Washington State Department of Ecology. This TIR has been prepared to fulfill a requirement of the permit application to The City of Edmonds Development Services Department (EDSD) and describes how the proposed project design complies with requirements established by the Edmonds Community Development Code (ECDC), prepared by The City of Edmonds, and the following specific guidance documents: 2019 Stormwater Management Manual for Western Washington, July (SWMMWW 2019); Edmonds Community Development Code, Title 18 Public Works Requirements, Chapter 18.30 Stormwater Management, effective January 1, 2017 (ECDC 2017); and Addendum to Edmonds Community Development Code Chapter 18.30 (Edmonds Stormwater Addendum) dated June 30, 2022 (ESA 2022). Per the ESA 2022, Figure 3.1 (Figure 3), Minimum Requirements 1 through 9 apply to new and replaced hard surfaces and converted vegetation. 1.1 EXISTING CONDITIONS SUMMARY The Property is an approximately 0.87-acre single-family residential parcel of land, northeast of the intersection of 2121h Street Southwest and 761h Avenue West. The Property is bordered by 2121h Street Southwest to the south and by adjacent private properties to the north, east, and west. Approximately 37,827 square feet of land on the Property and in the adjacent right-of-way is planned to be disturbed and restored with construction of the proposed redevelopment and associated improvements (herein referred to as the Site). Site improvement areas are confined largely within the boundaries of the Property, with limited work to occur within the adjacent 2121h Street Southwest right-of-way. Site areas are tabulated in Appendix A. Existing Site conditions are depicted on Figure 2. 1-1 CAC EKOIProjectslActive122017.01-Glacier-Headquarters\EngineeringUlM2024-07-Stormwater-TI R.docx Cf/<q, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com ccit-o Based on the U.S. Department of Agriculture National Resources Conservation Service Web Soil Survey Soil Resource Report (2022), the Site is underlain with Alderwood-Urban land complex with 2 to 8 percent slopes (Figures 4A through 4E). Alderwood-Urban land complex is a dense soil with a parent material of basal till. A project -specific geotechnical report is provided in Appendix B. The Site is identified on the Federal Emergency Management Agency (FEMA) Flood Insurance Rate Map No. 53061C1315F as being in a Zone X area (FEMA 2020). Zone X areas are those areas determined to be outside the 0.2 percent annual chance floodplain (Figure 5). On- and off -Property improvement areas are estimated to comprise a total of approximately 0.88253(') acre of the Site. The proposed improvements will follow the requirements of ECDC. The proposed Site improvements are anticipated to include the following: • A new approximately 2,788-square-foot (roof area) (') office building and a new approximately 4,488-square-foot (roof area) (') warehouse building; • Approximately 18,995 square feet(') of new concrete and/or asphalt pavement for parking, storage, vehicle access, and pedestrian areas; • Retaining wall(s); • Stormwater management facilities; • Right-of-way restoration related to connection of stormwater facilities to the municipal drainage system in the 2121h Street Southeast right-of-way; • On -Site utility improvements, both wet and dry; and • Landscaping improvements. Notes: (1) Site land cover areas described herein area pproxi mate. Measured Site land cover areas are provided in tabulated format in Appendix A of this report. 1-2 CAC EKOIProjectslActive122017.01-Glacier-Headquarters\EngineeringUlM2024-07-Stormwater-TI R.docx Cf/<q, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com ccit-o 2.0 DETERMINATION OF APPLICABLE MINIMUM REQUIREMENTS Per ESA Figure 3.1 (Figure 3), Minimum Requirements 1 through 9 apply to new and replaced hard surfaces and all disturbed land. Descriptions of how the project design meets each of the Minimum Requirements are discussed below. 2.1 MINIMUM REQUIREMENT 1: PREPARATION OF STORMWATER SITE PLANS Prepared in conjunction with this TIR, a preliminary stormwater site plan is provided as part of the project preliminary engineering plans. A final stormwater site plan, consistent with the requirements described in 2019 SWMMWW Volume I, will be prepared and submitted with the project engineering plans for the anticipated Design Review, Conditional Use, Land Use, and Clearing and Grading permit applications. 2.2 MINIMUM REQUIREMENT 2: STORMWATER POLLUTION PREVENTION PLAN A Construction Stormwater Pollution Prevention Plan will be prepared and submitted under separate cover with the anticipated Clearing and Grading permit application. 2.3 MINIMUM REQUIREMENT 3: SOURCE CONTROL OF POLLUTION Source control will be provided through the application of source control best management practices (BMPs) during construction, and on the developed Site following construction. BMPs will be appropriate for the proposed construction activities, buildings, facilities, and intended post -development Site uses in accordance with 2019 SWMMWW Volume IV. 2.4 MINIMUM REQUIREMENT 4: PRESERVATION OF NATURAL DRAINAGE SYSTEMS AND OUTFALLS The existing natural location of discharge is the public drainage system in 212th Street Southwest via sheet flow from the Property and is collected in catch basin(s) located in the 2121" Street Southwest right-of-way. The proposed design maintains the existing point of discharge to the 2121" Street Southwest municipal drainage system through a single point discharge. 2.5 MINIMUM REQUIREMENT 5: ON -SITE STORMWATER MANAGEMENT On -Site stormwater management BMPs will be provided in accordance with the requirements of 2019 SWMMWW Volume I, Chapters 2 and 4; Volume III, Chapter 3; Volume V, Chapter 5; and ECDC for Category 2 projects. Low Impact Development BMPs will be used as directed by the EDSD. 2-1 CAC EKOIProjectslActive122017.01-Glacier-Headquarters\EngineeringUlM2024-07-Stormwater-TI R.docx Cf/<q, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com cciCo Because the proposed Site improvements will include approximately 26,271 square feet(') of new or replaced impervious area and because of Site limitations rendering most on -Site stormwater BMPs infeasible, stormwater runoff from the Site areas will be managed via an on -Site stormwater detention and media filtration system. BMP infeasibility is discussed in Section 4. 2.6 MINIMUM REQUIREMENT 6: RUNOFF TREATMENT On -Site stormwater treatment facilities were designed to meet or exceed the following water quality treatment requirements: Oil control requirements specified in 2019 SWMMWW Volume V-3.2, Oil Control Menu. To meet this requirement, the stormwater treatment facilities were designed to achieve a goal of no ongoing or recurring visible sheen, and to have a 24-hour average total petroleum hydrocarbon concentration no greater than 10 milligrams per liter (mg/1) and a maximum of 15 mg/l for a discrete sample. Phosphorous control requirements specified in 2019 SWMMWW Volume V-3.3, Phosphorous Treatment Menu. To meet this requirement, the stormwater treatment facilities were designed to achieve a goal of 50 percent total phosphorous removal for a range of influent concentrations of 0.1 to 0.5 mg/I total phosphorous. Enhanced treatment requirements specified in 2019 SWMMWW Volume V-3.4, Enhanced Treatment Menu. To meet this requirement, the stormwater treatment facilities were designed to achieve performance goals of at least 80 percent removal of total suspended solids, at least 30 percent removal of dissolved copper, and at least 60 percent removal of dissolved zinc. Treatment facilities were sized using a multi -decade modeling period using the currently applicable and required software model, Western Washington Hydrology Model (WWHM), provided in Appendix C. 2.7 MINIMUM REQUIREMENT 7: FLOW CONTROL Because the proposed improvements will include new or replaced impervious surface greater than 10,000 square feet and the Site does not discharge to Puget Sound, stormwater runoff will be managed using an on -Site stormwater detention system. Stormwater runoff forthe proposed developed Site condition, as calculated using 15-minute time step increase in the 100-year recurrence interval flow using a continuous simulation runoff model, must match that of the predeveloped condition for all flows. The proposed Site stormwater system can be expected to meet this requirement. Modeling of the system using the WWHM verified the anticipated compliance. WWHM modeling reports are provided in Appendix C. Notes: (1) Site land cover areas described herein are approximate. Measured Site land cover areas are provided in tabulated format in Appendix A of this report. 2-2 C:ICEKOIProjectslActive122017.01-Glacier-Headquarters\EngineeringlTIR12024-07-Stormwater-TI R.docx 4011l LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com ccit-o 2.8 MINIMUM REQUIREMENT 8: WETLANDS PROTECTION An unnamed wetland is within 0.25 mile but is not downstream of the Site. No known wetlands are located downstream of the Site prior to the point of discharge to Halls Creek. 2.9 MINIMUM REQUIREMENT 9: OPERATION AND MAINTENANCE Operation and maintenance of the stormwater management facilities will be the responsibility of the applicant, and that responsibility will be passed to future owners. 2-3 CAC EKOIProjectslActive122017.01-Glacier-Headquarters\EngineeringUlM2024-07-Stormwater-TI R.docx Cf/<q, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com ccit-o 3.0 SITE ANALYSIS 3.1 OFF -SITE SUMMARY A review of downstream flow paths was performed as part of the project design work. Off -Site analyses consisted of inspection field walks of the project Site and downstream areas, review of topographic mapping of the Property and adjacent areas, and review of the City of Edmonds Geographic Information Systems database. 3.2 DOWNSTREAM ANALYSES Stormwater runoff from the Site generally is conveyed southward via sheet flow toward the municipal drainage system in the 2121" Street Southwest right-of-way. Stormwater is conveyed eastward via the municipal drainage system along the 2121" Street Southwest right-of-way, then southward along the 72nd Avenue West right-of-way, then eastward along 216th Street Southwest right-of-way. Pipe flows in the 216th Street Southwest right-of-way are conveyed eastward to an eventual point of discharge to Halls Creek, southeast of the intersection of 216th Street Southwest and Pacific Highway (Highway 99). Halls Creek is a tributary of Lake Ballinger. Downstream flow paths are shown on Figure 6. Halls Creek discharges to Lake Ballinger. Lake Ballinger is listed on the Washington State 303(d) list for failing to meet the U.S. Environmental Protection Agency human health criteria for total phosphorous and has requirements for total maximum daily load for phosphorous. Phosphorous control is included in the proposed stormwater treatment system. 3.3 UPSTREAM ANALYSIS The surrounding area is developed such that limited off -Property stormwater runoff drains onto the Property. The upstream areas that drain onto the Property are minor vegetated areas of the properties along the western boundary of the Property. Stormwater runoff from the west - adjacent properties infiltrates or is conveyed southward across the Property to the 212th Street Southwest right-of-way. The proposed design includes collection structures that will capture the minor runoff from the adjacent properties. The proposed stormwater conveyance system has adequate conveyance capacity for minor runoff addition from the adjacent properties. 3-1 CAC EKOIProjectslActive122017.01-Glacier-Headquarters\EngineeringUlM2024-07-Stormwater-TI R.docx Cf/<q, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com ccit-o 4.0 DEVELOPMENT LAYOUT A depiction of the proposed developed Site condition is provided as Figure 7, including proposed buildings, pavement, stormwater management system, retaining walls, and restoration of anticipated disturbed Site areas. 4.1 ON -SITE STORMWATER MANAGEMENT OVERVIEW A robust stormwater management system is proposed to control runoff from the proposed developed Site condition, and, per applicable requirements, to match the predeveloped condition of the Site. Summary of the proposed stormwater management system is provided in Section 4.3.2, Proposed Developed Site Hydrology and shown on Figures 7 and 9. 4.2 ON -SITE STORMWATER MANAGEMENT For this project, the following BMPs were considered: • Dispersion; • Afforestation; • Infiltration; • Bioretention; • Pervious pavement; and • Detention. The underlying glacial till soils provide limited infiltration; therefore, bioretention and infiltration were considered infeasible to manage stormwater fully. Because large enough areas of land to allow for partial or full dispersion or afforestation are not available on the Property, dispersion and afforestation also are not considered feasible. Pervious pavement is being considered for portions of the sidewalk on the Site. The only feasible singular BMP for on -Site stormwater management is detention. 4.3 FLOW CONTROL 4.3.1 Existing Site Hydrology Current Property conditions include a single-family residence built in 1940 with several smaller outbuildings and gravel and asphalt pavement. The Property is vegetated with native trees and other plant species, invasive species such as Himalayan blackberry and English ivy, and planted ornamental species. The Property also has landscaping improvements that include walls and concrete surfaces. 4-1 CAC EKOIProjectslActive122017.01-Glacier-Headquarters\EngineeringUlM2024-07-Stormwater-TI R.docx Cf/<q, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com ccit-o Stormwater runoff from the Site is conveyed via sheet flow southward toward 2121" Street Southwest. Runoff from the Site is conveyed to existing municipal drainage facilities in the 212th Street Southwest right-of-way. 4.3.2 On -Site Stormwater Best Management Practices As required by ECDC 2017 and ESA 2022, the following BMPs were considered for on -Site stormwater management. Where a BMP was determined to be infeasible, discussion of infeasibility criteria is provided. Infeasibility language from Appendix A of ESA 2022 is provided in italics. 4.3.2.1 Lawn and Landscaped Areas 4.3.2.1.1. Post -Construction Soil Quality and Depth This BMP will be applied to all areas of the Site that are disturbed and are proposed to be landscaped after construction. Areas within existing tree root zones will be excluded. 4.3.2.2 Roof Areas 4.3.2.2.1. Full Dispersion This BMP is considered infeasible because a minimum forested or native vegetation flowpath length of 100 feet cannot be achieved. 4.3.2.2.2. Downspout Fill Infiltration Systems This BMP is considered infeasible because the Site does not have outwash or loam soils. 4.3.2.2.3. Bioretention or Rain Gardens This BMP is considered infeasible because there is a lack of usable space for bioretention/rain garden areas and the only areas available for siting do not allow for a safe overflow pathways to stormwater drainage system or private storm sewer systems. 4.3.2.2.4. Downspout Dispersion Systems This BMP is considered infeasible because a vegetated flowpath at least 50 feet in length from the downspout to the downstream property line is not feasible. 4.3.2.2.5. Detention Vaults or Pipes This BMP is considered feasible and is implemented with the proposed arch tank detention facility. 4-2 CAC EKOIProjectslActive122017.01-Glacier-Headquarters\EngineeringUlM2024-07-Stormwater-TI R.docx Cf/<q, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com cciCo 4.3.2.2.6. Perforated Stub -Out Connections Per direction from City of Edmonds staff, Detention Vaults or Pipes are considered for feasibility prior to Perforated Stub -Out Connections. This BMP was not selected as a Detention Pipe system was selected. 4.3.2.3 Other Hard Surface Areas 4.3.2.3.1. Full Dispersion This BMP is considered infeasible because a minimum forested or native vegetation flowpath length of 100 feet cannot be achieved. 4.3.2.3.2. Permeable Pavements This BMP is considered infeasible for drivable pavement surfaces because the area will be subject to more than very low truck traffic. The site will be subject to daily traffic of utility trucks and trailers, and vehicles that will require static vehicle wheel turning movements. This BMP is considered infeasible for non -drivable pavement surfaces because they are within 50 feet of the top of slopes greater than 15 percent. 4.3.2.3.3. Bioretention This BMP is considered infeasible because there is a lack of usable space for bioretention/rain garden areas and the only areas available for siting do not allow for a safe overflow pathways to storm water drainage system or private storm sewer systems. 4.3.2.3.4. Sheet Flow Dispersion This BMP is considered infeasible because positive drainage for sheet flow runoff cannot be achieved due to the limited availability of suitable downslope areas and close proximity to existing downslope rockeries, proposed buildings, and property lines. 4.3.2.3.5. Detention Vaults or Pipes This BMP is considered feasible and is implemented with the proposed arch tank detention facility. 4.3.3 Proposed Developed Site Hydrology Site improvement areas, including on- and off -Property areas, are estimated to comprise approximately 0.88253 acre(') of land. After application of allowed tree credits, the modeled total Site area is estimated to comprise approximately 0.80425 acre('). Notes: (1) Site land cover areas described herein are approximate. Measured Site land cover areas are provided in tabulated format in Appendix A of this report. 4-3 CAC EKOIProjectslActive122017.01-Glacier-Headquarters\EngineeringMR12024-07-Stormwater-TI R.docx CC/CO, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com cci<7 The proposed improvements will follow EDSD requirements. Proposed Site improvements are anticipated to include the following: • Surface collection and conveyance via roof drains, paved surfaces, and paved gutters. • Collection from on -Site pavement surface areas at catch basins. • Oil control, presettling, and wet volume detention in large Type 2 catch basins with floatables and oil -control tees on the outlets. • Conveyance via pipes. • Detention of collected flows in an arch tank facility to be located below the paved portions of the Site parking and driveway areas. • Attenuation of runoff flows via a flow control "Tee" structure. • Runoff water quality treatment via a proprietary media filter drain. • Discharge via pipe to the existing municipal drainage system in the 212th Street Southwest right-of-way. The predeveloped Site condition is assumed to be a fully forested condition rather than the existing impacted condition of the Site. The developed Site condition is assumed to be as depicted on Figure 7. Computer modeling of stormwater runoff for the predeveloped and proposed developed Property conditions was completed to demonstrate compliance with EDSD requirements. Per BMP T5.16 of 2019 SWMMWW, impervious area credits for retained trees were applied to impervious areas in the project WWHM modeling, excluding those trees retained in the north portion of the, which was modeled as forested in both the predeveloped and developed conditions. Also per BMP T5.16 of 2019 SWMMWW, impervious area credits for proposed planted trees were applied to impervious areas in the project WWHM modeling. Credits are tabulated and summarized in Appendix A and on Figure 8. Reporting documents generated from WWHM modeling (Appendix C) demonstrate that the proposed stormwater facilities will meet the Category 2 flow control requirements that estimated mitigated runoff flow rates after development are equal to or less than the estimated predeveloped runoff flow rates for the Property. Because the current conditions are developed, and not in a native forested condition, downstream areas should experience greater attenuation of peak runoff flows as compared to current conditions. 4.4 WATER QUALITY SYSTEM Enhanced treatment, and phosphorus and oil control are required for the Site as summarized in Section 2.0, Determination of Applicable Minimum Requirements. To meet these requirements, a treatment train of presettling and oil control structures and a proprietary media filter vault will be incorporated as part of Site development. Oil control and presettling for runoff from each of 4-4 CAC EKOIProjectslActive122017.01-Glacier-Headquarters\EngineeringMR12024-07-Stormwater-TI RAocx CC/CO, CLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com cciCo the four on -Site subbasins will be provided by Type 2 catch basins designed to meet the requirements of 2019 SWMMWW, as shown on Figure 8. Stormwater flow from the four collection structures will be conveyed to the detention system and flow control structure. Stormwater will be conveyed through the flow control structure to a proprietary media filter vault to meet the enhanced treatment and phosphorous control requirements. The preliminary stormwater management system schematic diagram is provided on Figure 9. Water quality facility sizing calculations are provided in Appendix D. 4-5 CAC EKOTrojectslActive122017.01-Glacier-Headquarters\EngineeringUlM2024-07-Stormwater-TI R.docx Cf/<q, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com ccit-o 5.0 CONVEYANCE SYSTEM ANALYSIS AND DESIGN The stormwater system elements have been sized to convey the estimated peak stormwater flow adequately. Preliminary conveyance capacity calculations for the proposed stormwater management system are provided in Appendix E. Final conveyance capacity calculations for the proposed stormwater management system will be added to Appendix E of the final issuance of this report, after the Property design has been finalized. 5-1 CAC EKOIProjectslActive122017.01-Glacier-Headquarters\EngineeringUlM2024-07-Stormwater-TI R.docx 400/<9Z LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com ccit-o 6.0 SPECIAL REPORTS AND STUDIES Krazan & Associates, Inc. 2022. Geotechnical Engineering Investigation Proposed Glacier Offices and Warehouse, 7509 2121" Street Southwest, Edmonds, Washington 98026. Prepared for Glacier Environmental Services, Inc. February 4. 6-1 CACEK0\Projects%ctivet22017.01-Glacier-HeadquarterslEngineedng\TI R12024-07-Stormwater-TIR.docx OCEW411A LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com ccit-o 7.0 OTHER PERMITS The following permits are anticipated to be required for the proposed Site improvements: City of Edmonds Design Review; City of Edmonds Conditional Use Permit; City of Edmonds Land Use Approval; City of Edmonds Clearing and Grading; City of Edmonds Building Permits; City of Edmonds Right -of -Way Permit; City of Edmonds Right -of -Way Use Permit; and Washington State Department of Labor & Industries Electrical Permit. Because the Site is less than 1 acre of land, a Washington State Department of Ecology Construction Stormwater General Permit is not anticipated to be required. Other required permits may be identified as the permit application and review process progresses. These permits will be added to this list with the final issuance of this TIR. 7-1 CAC EKOIProjectslActive122017.01-Glacier-Headquarters\EngineeringUlM2024-07-Stormwater-TI R.docx 400/<9Z LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com ccit-o 8.0 OPERATION AND MAINTENANCE MANUAL An operation and maintenance manual is provided in Appendix F. 8-1 CACEK01Projects%ctivet22017.01-Glacier-HeadquarterslEngineedng\TI R12024-07-Stormwater-TIR.docx OCEW411A LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com ccit-o 9.0 SECURITY DEVICE Documentation establishing the appropriate security device(s) and amount(s) have been provided under separate cover. 9-1 CACEKO1Projects%ctivet22017.01-Glacier-HeadquarterslEngineedng\TI R12024-07-Stormwater-TIR.docx OCEW411A LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com cc -IC" 10.0 REFERENCES Washington State Department of Ecology. 2019. 2019 Stormwater Management Manual for Western Washington. July. City of Edmonds, Washington. 2017. Edmonds Community Development Code, Title 18 Public Works Requirements, Chapter 18.30 Stormwater Management. January 1. ---. 2022. Addendum to Edmonds Community Development Code Chapter 18.30. June 30. ---. 2019. City of Edmonds Geographic Information System Database Search. <https://maps.edmondswa.gov/Html5Viewer/?viewer=Edmonds SSL.HTML > (February 24, 2021. ) Federal Emergency Management Agency (FEMA). 2020. Flood Map Service Center. <https:Hmsc.fema.gov/portal/home>. (February 22, 2022.) Krazan & Associates, Inc. 2022. Geotechnical Engineering Investigation Proposed Glacier Offices and Warehouse, 7509212th Street Southwest, Edmonds, Washington 98026. Prepared for Glacier Environmental Services, Inc. February 4. U.S. Department of Agriculture Natural Resources Conservation Service. 2022. Web Soil Survey Soil Resource Report Search. <https:Hwebsoilsurvey.sc.egov.usda.gov/App/WebSoilSurvey.aspx>. (February 22, 2022.) Washington State Department of Ecology. 1993. Ballinger Lake Total Phosphorus Total Maximum Daily Load. Publication No. 93-10-202. 10-1 CAC EKOIProjectslActive122017.01-Glacier-Headquarters\EngineeringMR12024-07-Stormwater-TI RAocx CC/CO, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com cciCo FIGURES TECHNICAL INFORMATION REPORT 212t" Street Site Redevelopment Edmonds, Washington CEKO PN: 22017.01 CAC EKO\Projects\Active\22017.01-Glacier-Headquarters\Engineering\TIR\2024-07-Stormwater-TI R.docx CC/CO, KA C ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com REFERENCE: 7.5 MINUTE USGS QUADRANGLE EDMONDS EAST, WASHINGTON. DATED 2020 c EDMONDS EATTLE WASHINGTON Civil Engineering and Consulting 2255 Squak Mountain Loop SW Issaquah, Washington 98027 (425) 864-8246 FIGURE 1 SITE LOCATION MAP 212TH STREET REDEVELOPMENT 7509 212TH STREET SOUTHWEST EDMONDS, WA -1, H 0 20 SCALE IN FEET I I I I I I U O O Y t U W O Ln r� N O CY O U I (!) �X W I N I Li ry in Q) cy I_� 0 N N 0 Q U Q In L Q� C) I Q) U O CD I 0 N N O U Q U a� O n CD U U 9 tltd6 416Z�104 J,G - I \1 434.7 � L 1 t cE+ b CIF EN 0.11E OF°i PROP UN& yJIB' 5.3� I 121' II II L kR I FF )r I 7 1 Y f:::.:.:.:::::::::::::::::::::::::::::::.: .: . I 19'ARB Oy6NL -\- 0 I QO�•� I .......... I 41'ARB GRM0. .;.'.' 0.41OF E OF ." ..... . .. . I PROP UNE I I' ....... /79 II I °0 211 37.4'— I 1 I I 17'ARB I EDGE O �sfi2 PROP PROLINE 11NE .. 24"AR11 I — 1 I .... M83 EAW EAW I I I'•' O I OTY OF EDM DIRECTIONAL SIGN I O #84 47'ARB SET REBAR/C / AT PROP COR 7 I •• .. E I PoM=4ffi74' .......... (PNWD ON) I p 0 1E 'F UGC4. U(�w IE(SE) 1 7P1C= 418b9' APPROX. L.00A11014PER---"'- W RECORDS HAWIA9Y � IE( 1Y 1"ss �- SD E(S) ,fWf--418.08' IE(NIY) IfOW 4K31' / 0 LANE STRIPING i NCE COR ON LINE OF CO2 PROP 111E �\ SITE LOW POINT AND ASSUMED EXISTING POINT OF DISCHARGE. \ EASEMENTS \ PER AFN 11111602170520 >L/JG \ tRaP Cut HP -BHP 1� ) — k— 1) O N PoM-413 T E(S) 8' =-411AS SD SD SD SD SD SD PoM-414.45 S S IEE((S 12MIC - SS SS SS S SS 'Em 1r � . IE(" 9'COND-M15 Cn 41cw41c�ffw1rf7 Civil Engineering and Consulting 2255 Squak Mountain Loop SW Issaquah, Washington 98027 (425) 864-8246 FIGURE 2 EXISTING CONDITIONS 212TH STREET REDEVELOPMENT 7509 212TH STREET SOUTHWEST EDMONDS, WASHINGTON CEKO PN: 22017.01 DATE: 07/31/2024 Does the project result in 2.000 square feet, or greater, of new plus replaced hard surface area,' OR Does the land disturbing activity total 7,000 square feet or greater? es No Minimum Requirements No. I through 5 apply I Minimum Requirement No. 2 applies Next Question Does the project add 5,000 square feet or more of new plus replaced hard surfaces? OR Convert 0.75 acres or more of vegetation to lawn or landscaped areas? OR Convert 2.5 acres or more of native vegetation to pasture? Is this a road related project'? All Minimum Requirements apply to the new and replaced hard surfaces and converted vegetation areas. All Minimum Requirements apply to the new hard surfaces and converted vegetation areas. Yes No Yes Does the project add 5,000 square feet or No more of new hard surfaces? Yes Do new hard surfaces add 50% or moire to the existing hard surfaces within the project limits? No Figure 3.1. Flow Chart for Determining Requirements for Development. REFERENCE: CITY OF EDMONDS STORMWATER AMENDMENT. DATED 2022 Civil Engineering and Consulting 2255 Squak Mountain Loop SW Issaquah, Washington 98027 (425) 864-8246 No additional requirements. FIGURE 3 FLOW CHART FOR DETERMINING REQUIREMENTS FOR DEVELOPMENT 212TH STREET REDEVELOPMENT 7509 212TH STREET SOUTHWEST EDMONDS, WASHINGTON CEKO PN:22017.01 DATE: 07/31 /2024 3; Soil Map —Snohomish County Area, Washington 3 >r 549M SQ780 5QM 54MM 5wo 54wo 549M SM40 5 o io 54M Saao= � 47° 48' 29' N 67° 4629" N N f?I 8 � � _ S 8 F r o_ a o — ii O sur N 7S$f1 In W t i N ii_ WNW 549M 54M 54%10 51FB20 549070 549M 54OW 54M 549KM � 3 3 Map Scale: 1:681 f prri ed on A porva¢ (85' x 11') 11eet. N Q N Miters 0 10 2D 40 60 U 12 ` � a � so 120 180 A r m Map poeon: Web Metorix Carter ad ates: WGS84 Edge bcs: t11M Zone 10N WGS84 LSL1A Natural Resources Web Soil Survey 212212022 _ � Conservation Service National Cooperative Soil Survey Page 1 of 3 REFERENCE: US DEPARTMENT OF AGRICULTURE, NATURAL RESOURCES CONSERVATION SERVICE WEB SOIL SURVEY. 2022. s FIGURE 4A 0 USDA NRCS 3 Civil Engineering and Consulting MAP 0 2255 Squak Mountain Loop SW 212TH STREETSOLILS REDEVELOPMENT o Issaquah, Washington 98027 7509 212TH STREET SOUTHWEST 864-8246 EDMONDS, WASHINGTON 'du(425) CEKO PN:22017.01 DATE:07/31/2024 Soil Map —Snohomish County Area, Washington MAP LEGEND MAP INFORMATION Area of Interest (Aol) !4 Spoil Area The soil surveys that comprise your ACII were mapped at Area of Interest (AOI) O Stony Spot 1:24.000. Soils Very Stony Spot Warning: Soil Map may not be valid at this scale. Sal Map Unit Polygons 17 wet Spot Enlargement of maps beyond the scale of mapping can cause .,� Soil Map unit Lines misunderstanding of the detail of mapping and accuracy of soil Other line placement. The maps do not show the small areas of Sal Map Unit Points I Special Line Features contrasting soils that could have been shown at a more detailed Special Point Features scale. V Blowout Water Features Streams and Canals Please rely on the bar scale on each map sheet for map ® Borrow Pit measurements. Transportation X Clay Spot � Rails P� Source of Ma Natural Resources Conservation Service Closed Depression Web Soil Survey URL: ti Interstate Highways Coordinate System: Web Mercator (EPSG:3857) rill Gravel Pit US Routes Maps from the Web Soil Survey are based on the Web Mercator Gravelly Spot Major Roads projection, which preserves direction and shape but distorts distance and area. A projection that preserves area. such as the O Landfill Local Roads Albers equal-area conic projection, should be used if more A Lava Flow accurate calculations of distance or area are required. Background dilr Marsh or swamp . Aerial Photography This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Mine or Quarry Soil Survey Area' Snohomish County Area, Washington ® Miscellaneous Water Survey Area Data: Version 23, Aug 31, 2021 O Perennial Water Soil map units are labeled (as space allows) for map scales 'Y Rock Outcrop 1 50,000 or larger. + Saline Spot Date(s) aerial images were photographed Sap 2, 2018—Sep 25, 2018 Sandy Spot The orthophoto or other base map on which the soil lines were 4W Severely Eroded Spot compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor Q Sinkhole shifting of map unit boundaries may be evident. �j. Slide or Slip + Sodic Spot USDA Natural Resources U Conservation Service Web Soil Survey National Cooperative Soil Survey REFERENCE: US DEPARTMENT OF AGRICULTURE, NATURAL RESOURCES CONSERVATION SERVICE WEB SOIL SURVEY. 2022. Civil Engineering and Consulting 2255 Squak Mountain Loop SW Issaquah, Washington 98027 (425) 864-8246 FIGURE 4B USDA NRCS SOILS MAP LEGEND 212TH STREET REDEVELOPMENT 7509 212TH STREET SOUTHWEST EDMONDS, WASHINGTON 2/22/2022 Page 2 of 3 Soil Map —Snohomish County Area, Washington Map Unit Legend Map Unit Symbol Map Unit Name Acres in A01 Percent of A01 5 Alderwood-Urban land complex, 2 to 8 percent slopes 09 100.0% Totals for Area of Interest 0.9 100.0% USDA Natural Resources Web Soil Survey Conservation Service National Cooperative Soil Survey REFERENCE: US DEPARTMENT OF AGRICULTURE. NATURAL RESOURCES CONSERVATION Civil Engineering and Consulting 2255 Squak Mountain Loop SW Issaquah, Washington 98027 (425) 864-8246 2/22/2022 Page 3 of 3 WEB SOIL SURVEY. 2022. FIGURE 4C USDA NRCS SOILS MAP LEGEND DESCRIPTION 212TH STREET REDEVELOPMENT 7509 212TH STREET SOUTHWEST EDMONDS, WASHINGTON Map Unit Description; Aide nvood-Urban ;and complex, 2 to 8 percent slopes ---Snohomish County Area. Washington Snohomish County Area, Washington 5—Alderwood-Urban land complex, 2 to 8 percent slopes USDA Natural Resources !1" Conservation Service Map Unit Setting National map unit symbol: 2hz9 Elevation: 50 to 800 feet Mean annual precipitation: 25 to 60 inches Mean annual air temperature: 48 to 52 degrees F Frost -free period: 180 to 220 days Farmland classification: Not prime farmland Map Unit Composition Alderwood and similar soils: 60 percent Urban land: 25 percent Minor components: 15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Alderwood Setting Landform: Till plains Parent material. Basal till Typical profile H1 - 0 to 7 inches. gravelly ashy sandy loam H2 - 7 to 35 inches: very gravelly ashy sandy loam H3 - 35 to 60 inches. gravelly sandy loam Properties and qualities Slope: 2 to 8 percent Depth to restrictive feature: 20 to 40 inches to densic material Drainage class. Moderately well drained Capacity of the most limiting layer to transmit water (Ksat): Very low to moderately low (0.00 to 0.06 in/hr) Depth to water table. About 18 to 36 inches Frequency of flooding. None Frequency of ponding. None Available water supply, 0 to 60 inches: Low (about 3.0 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated). 4s Hydrologic Soil Group: B Ecological site, F002XA004WA - Puget Lowlands Forest Forage suitability group: Limited Depth Soils (G002XN302WA) Other vegetative classification: Limited Depth Soils (G002XN302WA) Hydric soil rating: No Web Soil Survey National Cooperative Sod Survey REFERENCE: US DEPARTMENT OF AGRICULTURE, NATURAL RESOURCES CONSERVATION SERVICE WEB SOIL SURVEY. 2022. Civil Engineering and Consulting 2255 Squak Mountain Loop SW Issaquah, Washington 98027 (425) 864-8246 2122i 2022 Page 1 of 2 FIGURE 4D USDA NRCE SOILS MAP UNIT DESCRIPTION 212TH STREET REDEVELOPMENT 7509 212TH STREET SOUTHWEST EDMONDS, WASHINGTON Map Unit Description; Aldenvood-Urban and complex, 2 to 8 percent slopes ---Snohomish County Area. Washington Minor Components Norma, undrained Percent of map unit: 5 percent Landform: Depressions Other vegetative classification: Wet Soils (G002XN102WA) Hydric soil rating. Yes Mckenna Percent of map unit: 5 percent Landform: Depressions Other vegetative classification: Wet Soils (G002XN 1 02WA) Hydric soil rating: Yes Terric medisaprists, undrained Percent of map unit: 5 percent Landform: Depressions Other vegetative classification: Wet Soils (0002XN102WA) Hydric soil rating: Yes Data Source Information Soil Survey Area: Snohomish County Area, Washington Survey Area Data: Version 23. Aug 31, 2021 USDA Natural Resources Web Soil Survey 11" Conservation Service National Cooperative Sod Survey 2122i 2022 Page 2 of 2 REFERENCE: US DEPARTMENT OF AGRICULTURE, NATURAL RESOURCES CONSERVATION SERVICE WEB SOIL SURVEY. 2022. Civil Engineering and Consulting 2255 Squak Mountain Loop SW Issaquah, Washington 98027 (425) 864-8246 FIGURE 4E USDA NRCS SOILS MAP UNIT DESCRIPTION 212TH STREET REDEVELOPMENT 7509 212TH STREET SOUTHWEST EDMONDS, WASHINGTON National Flood Hazard Layer FIRMette 12I'2'23'•W 47'4898"n 4 04 SITE LOCATION • t . I i 1' •F • f. ` w n.c i L� 1 m I` • 1 ■1 _ ' 1 ,FFNI Legend VIP 1 . •� 1 i fis. 4 rou Feet 1-16,000 il— 9E "191-<a ill N 0 250 500 1,500 2,000 Basemap: USGS National Map: Ortholmagery: Data refreshed October, 2020 SEE FlS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT Without Base Flood Elevation (BFE) Zme A y, A99 SPECIAL FLOOD With RIFE or Depth 7— 4F. AO, AN, vE AR HAZARD AREAS Regulatory Floodway 0.2%Annual Chance Flood Hazard, Areas of 1% annual chance flood with average depth less than one loot or with drainage areas of less than one square mile Future Conditions 1%Annual Chance Flood Hazard . Area with Reduced Flood Risk due to OTHER AREAS OF Levee, See Notes. FLOOD HAZARD Area with Flood Risk due to Levee: No scwfN Area of Minimal Flood Hazard Q Effective LOMRs OTHER AREAS Area of Undetermined Flood Hazard _. GENERAL ---- Channel, Culvert. or Storm Sewer STRUCTURES 1 1 11 1 1 1 Levee, Dike. or Floodwall p zO•z Cross Sections with 1% Annual Chance +Ts Water Surface Elevation — — — Coastal Tiansect Base Flood Elevation Une (BFE) Umit of Study Jurisdiction Boundary -•— Coastal Transact Baseline OTHER _ Profile Baseline FEATURES Hydrographic Feature Digital Data Available N No Digital Data Available MAP PANELS Unmapped 0 The pin displayed on the map is an approximate point selected by the user and does not represent an authoritative property location. This map complies with FEMA's standards for the use of digital flood maps If It is not void as described below. The Dasemap shown complies with FEMA's basemap accuracy standards The flood hazard Information Is derived directly from the authoritative NFHL web services provided by FEMA. This map was exported on 2i 22:'2022 at 6:38 PM and does not reflect changes or amendments subsequent to this dale and time. The NFHL and effective information may change or become Superseded by new data over time. This map image Is void If the one or more of the following map elements do not appear: baserrap Imagery, flood zone labels, legend. scale on map creation date. community Identifiers, FIRM panel number, and FlRM effective date. Map images for unmapped and unmodernlzed areas cannot be used for regulatory purposes. FIGURE 5 Civil Engineering and Consulting FEMA FLOOD HAZARD MAP Civil Sgne Mountain Loop SW 212TH STREET REDEVELOPMENT 2255 Issaquah, Washington 98027 7509 212TH STREET SOUTHWEST (425) 864-8246 EDMONDS, WASHINGTON CEKO PN:22017.01 DATE:07/31/2024 - — iai ••7.f'.!m R _��NONE 66 lip in :� - - .i•■r,•r; _1 , >: • t - -•. — _1� ,�. as ■; . t �� I c t a 1 _ . �_� .�` I 'i�i7 , - Ij jai 0 —T� ''n • •Y _ lowAo •• 1 llE: ,, _ ✓'� ._ '•` ,I._ (� �: �, 1 Z ■ I Lail Now � I pill; fit `� 1) -.- '1 _ ��.. G _$ III �� , r •`� -�• ■ ■ /!`�-1 - ely l•,_4 •� • r I �` ` ' �• y��'J ' Is ~ f t �' f '�• t� � `mew '�-_--I..O•.. �t I : 11 � .•Il I • ■ � ■ ■ � .� 1 '-- ', II � �� •Yt'— D�I ■- lip It ,vim Is 0 PIPEDm I low CONVEYANCE it I SYTSTEM� AID _ / IN w .� uj !075 -, �Iqo.. � � - :'t 1�: I I � II 1 . D , , � ; � — _ ~ - � � = � +''--Z�Z� ° ti •• �. � :'�• . �` • � ti=� " •, �9�tt - /� 1�: a 2 13TTi PL 5W , e i1>r�a� -?i� . ■� — _ , ( ♦: , .�f 'Wj=lD �t • lyre • ■-i —-Ct �l �� . ti • -� ` { I ' is t' .1 s9t■ « »_ • l s r '�`,.'MD moor — _ - ,� • a f 11 _ .--aw•+. � �,. , ► � - M � 5 � � � G Jl t i�i, • . I Yu M off„ �►. ,• . v• pit 1 • I - I I I _ — _.... •1_ . '�� r •It V` ••• �`-, • r — —mow_— ST. -_ • lllllllll l ■ f1 1- �I l I ff �V _ C11 p ' -[ •' J - - ' . �' lye 2 s7•! AW :p ` �•' , . t I fir, �'` �� I _ '�-t. � --- � � .1�1 7. '.tom ' _ ,' •�. ':� _��r� _ • p +,�, ,�_ c •�'' �� •: _ �" ■ icy �"�` _, � � ,.�'� i ,S1 ICU "'�'---►-- - .�J - � r l 89z1.47" 0 20 I SCALE IN FEET I I I I OF COR 2 00 OOy g00�\C\G �,G P� e P9pOpP ID Goyo��F,\9 1eW OF h 0.9'S FI PROP CDR L = • 15'Ev CIF PROP LIHE 1, T2-72" \ PRESETTIJNG STRUCTURE RIM=419.60 / 0.5'E OF e / IE(S) 6"DIP=417.50' PROP LINE / 1 W/ TEC e.0 \ e fig. BOTTOM ELEV.=408.00 I � , I I 8'CED I I CLF INTX 0.1'W OF PROP LINE I I I 1 I 1 + I I i mI I i I I i \ I I \ I I I \ I \ I \ CLF 0SE OF PROP LINE / / CLF ENI ARCH TANK DETENTION SYSTEM STORMKEEPER SK75 (OR EQUAL) EACH ROW 206.50-LF OF CHAMBERS EACH ROW WITH 2 ENDCAPS LOWEST FG ELEV. = 419.25 I STONE COVER TOP = 417.75 I I CHAMBER TOP = 417.25 CHAMBER BOTTOM = 414.75 i I ISTONE BED BOTTOM = 414.25 I I I I I I I � I I I I II I I I I II I I I I EAE EAVE -7-LF 24" SD 0-0.07. CITY OF EDMCN DIRECTIONAL SIGN _6-LF 10" SD SET REBAR/CA 0-0.5% IAT PROP CO� \I BIOPOD 4x4 VAULT I RIM=419.10f' PoM�2A74' (PA �+) IE(N) 10"SD=414.70' I I ° / IE(SE) 10'SD=412.50' TF� W/ BYPASS e 'e NW CRW VALT LID \ n UGC E1111ME1FTY.�1►Bo . TEL VLT U C� RM--41mr-- IE(S, 12'K1 k\g. 418.89' W W WV APPROX LOCATION �V U, f RECORDS (TYP) RLk419.95 S. gro8DPH878 E(E)1zar4�t5T3 SID SD ------SD= E(S) 1270304I& ' IF(MA) 12'004P416.31' - - - O ati IX IE(NX wM=4lasS9,11� 8'CONC-409.4S(GC) / I 0-18.59�4" DIP 3r S I i i I / z -7-LF 6" DIP / ®MIN.-38.9V. ''✓ CB-010 T2-72" PRESETTIJNG STRUCTURE I warm-iaE I RIM=419.72t' IULONG O�ti� / IE(S) 6"DIP=417.50' F = 420.50 I I / W/ g BOTTOM ELEV.=411.00 / I 1110111 -11-LF 12" SD .II ratio CB-009, T2-48" w RIM=419.50f' IE(W) 12"SD=415.00' ; O IE,SE) 8"RD=415.50� / I / �19.5% / / / #1 w ¢ a �• Y / -.QE CB-008, T2-72" / 0.2'E OF PROP LINE GFj'�'O\005 \YG 010-y'LQ�OQ 4,Ga� OF G�,\"p0\OAS v,G LINE O\Oe QOOpe�F1'\\ F CDR OF LINE REBAR/CAP PRESETTllNG STRUCTURE RIM=419.00±' F IE(SW) 6"DIP=417.25' W IvpwE2: TEE I I OFFICE BUILDING AND IMMEDIATELY W/ ADJACENT PAVED SIDEWALK. - F- e BOTTOM ELEV.=408.50 - _ _ _ AREA TO BE GRADED TO SUBGRADE ELEVATION, a ROLLED TO FIRM, AND STABILIZED WITH CRUSHED ROCK. III I I I I VE NCI 0.NC 3 g PROP N Iz A CFACE CB-004, T2-60" BULDIrvG RIM=419.25t' FFE - 420•OD w .9' IE(N) 24"SD=414.75' I I I I IE(SE) 6"DIP=415.75 IE(S) 10"SD=414.75' w 5 I W/ CONTROL STRUCTURE INI KI s I P OF UNE v`vI CB-005, T2-60" I �14-LF 6 " DIP PRESETTLING STRUCTURE RIM=418.50f' I NCE CDR IE(NW) 6"DIP=417.00' ON LINE I (U J 3 W/ TEE I SUMP ELEV.=410.50 I .. \COR "� 4 - - __- ____ ___ �S ---------- Trf - 'L- r OUND REBAR/CAP \ ON LJHE581� I - RIM=417.75t' \ IE(N) 6"FD=413.10' - - \ \ \ O M NO. 8 - / • _ ;a 9r - - IE(NW) 10"SD=411.75' -E - ELECTRICAL \ \ I E - - - E _ IE(S) 10'DIP=411.65' EASEMENT \ \ PER o2 70520 I 22- PROP \ OCR -44-LF 10" SD y �1.7% � 10" DIP -SPEED LIMIT scr1E I � C�0.77% , , 42 &-0.77 p _ _ VA D R H I VANED GRATE FIGURE 7 - 3 1 - - RIM=413.63' I w IE(E) 12°DIP=411.43' IE(S) EX. 8"GONG=411.43' _ 10. PIA a - - p / ,I AT PROP CDR V UTILITY Y CROSSING CONDUIT BOTTOM=412.75_W WE STRIPIN ^73.5-LF 12DIP ° W (!IIgS)(APSss'> o 4+,,s SD DIP TOP=412.60 hnf 0-0.27% At _- FIB=_EE --- Ela===- -212TEII-s .------ _____ ___ ___ -- ----- ------->�,�----SEf�====___ - \ (PUBUC RIGHT OF WAIF c6-001, Ti VANED GRATE \ [yip �N� -17-Lfc LM 8"CONC. SD SD SD - - ` \ -RIM=416.41t' - , 0-13.6% - - - SS /' SS. SS IE(N) 10"DIP=411.55' " SS S MM-414.46 S;ENIt00NG=omen- SS SS IE(E) 12DIP=411.55 4S) eXNC-4" Iq" B'O20=40821Y (/7 IE(W),Y.15 IEw exHO. 0B.15 Civil Engineering and Consulting PROPOSED CONDITIONS -SD SD 2255 S uak Mountain LoopSW 212TH STREET REDEVELOPMENT �' a Issaquah, Washington 98027 7509 212TH STREET SOUTHWEST SS s ss- (425) 864-8246 EDMONDS, WASHINGTON `� CEKO PN: 22017.01 DATE: 07/31/2024 0 20 I SCALE IN FEET I I I I i ■ ■ ■ O - - C5.2.21 OM'4i "3UBBASIN N2 5,194-S F IMPERVIOUS ■ ■ ■ ■ ■ ■ ■ ■ ■.N I ■ SUBBASIN N1 8,254-SF IMPERVIOUS (INCL.-4,488-SF ROOF) `S-20 ■ C5.21 f iiy ■1 ■ ■ ■__■� ■A" tN-■-■ t SUBBASIN C 6,006-SF iM-.= C lil ■ra��mo -A -20 SUBBASIN S 5,486-SF IMPERVIOUS (INCL.-2,788-SF ROOF) L' M! ------ - - - - -- u' —♦��' 212TH ST SW O - PROJECT HARD SURFACES AREAS SUMMARY COSTING CONDITIONS: EXISTING ON -SITE AREAS: EXISTING ON -SITE FORESTED AREA: -4,248-SF EXISTING ON -SITE LANDSCAPE AREAS: -22,505-SF EXISTING ON -SITE ROOF AREAS: -2,571-SF EXISTING ON -SITE PAVED AREAS: -8,503-SF TOTAL EXISTING ON -SITE AREA: -37,827-SF EXISTING ON -SITE TOTAL IMPERVIOUS AREA: -11,074-SF EXISTING ON -SITE PERCENT IMPERVIOUS: -29.28% EXISTING OFF -SITE AREAS: EXISTING OFF -SITE PAVED AREAS: -616-SF TOTAL EXISTING OFF -SITE AREA: -616-SF EXISTING OFF -SITE TOTAL IMPERVIOUS AREA: -616-SF EXISTING OFF -SITE PERCENT IMPERVIOUS: -100/ PROPOSED CONDITIONS - ON -SITE AREAS: PROPOSED ON -SITE FORESTED AREA: -4,248-SF PROPOSED ON -SITE LANDSCAPE AREAS: -7,308-SF PROPOSED ON -SITE ROOF AREAS: -7,276-SF PROPOSED ON -SITE PAVED AREAS: -18,995-SF TOTAL PROPOSED ON -SITE AREA: -37,827-SF PROPOSED ON -SITE TOTAL IMPERVIOUS AREA: -26,271-SF PROPOSED ON -SITE PERCENT IMPERVIOUS: -69.457. OFF -SITE AREAS: PROPOSED OFF -SITE PAVED AREAS: -616-SF TOTAL PROPOSED OFF -SITE AREA: -616-SF PROPOSED OFF -SITE TOTAL IMPERVIOUS AREA: -616-SF PROPOSED OFF -SITE PERCENT IMPERVIOUS: -1007. TREE CREDITS: TREE RETENTION: PROPOSED ON -SITE TREE RETENTION CREDIT AREA: -2,070-SF PROPOSED ON -SITE TREE PLANTING CREDIT AREA: -1,280-SF PROPOSED OFF -SITE TREE PLANTING CREDIT AREA: -60-SF WWHM MODELED CONDITIONS: ON -SITE AREAS: PROPOSED ON -SITE FORESTED AREA: -4,248-SF PROPOSED ON -SITE LANDSCAPE AREAS: -7,308-SF PROPOSED ON -SITE ROOF AREAS: -7,276-SF PROPOSED ON -SITE PAVED AREAS: -15,645-SF OFF -SITE AREAS: PROPOSED OFF -SITE PAVED AREAS: -556-SF NEW AND REPLACED IMPERVIOUS AREA SUMMARY - ON -SITE NEW AND REPLACED IMPERVIOUS AREAS: REPLACED ONSITE ROOF AREAS: -2,751-SF NEW ONSITE ROOF AREAS: "4,525-SF REPLACED ONSITE PAVED AREAS: "8,503-SF NEW ONSITE PAVED AREAS: "10,492-SF OFF -SITE NEW AND REPLACED IMPERVIOUS AREAS: REPLACED ONSITE PAVED AREAS:-616-SF NOTES: 1. NO IMPERVIOUS AREAS FROM THE SITE EXISTING CONDITIONS WILL BE RETAINED. 2. FOR PURPOSES OF SIZING THE PROPOSED WATER QUALITY TREATMENT FACILITIES, AND BECAUSE RUNOFF FROM ALL IMPERVIOUS AREAS WILL BE COMMINGLED, ALL IMPERVIOUS AREAS WERE INCLUDED AS POLLUTION GENERATING IMPERVIOUS SURFACES. 3. BECAUSE THE PROPOSED WATER QUALITY TREATMENT FACILITIES ARE POSITIONED DOWNSTREAM OF THE DETENTION FACILITY, RUNOFF FROM ROOF AREAS WAS INCLUDED IN SIZING OF THE PROPOSED WATER QUALITY TREATMENT FACILITIES. i CCl�O Civil Engineering and Consulting 2255 Squak Mountain Loop SW O Issaquah, Washington 98027 (425) 864 8246 FIGURE 8 SITE DRAINAGE AREAS 212TH STREET REDEVELOPMENT 7509 212TH STREET SOUTHWEST EDMONDS, WASHINGTON CEKO PN: 22017.01 DATE: 07/31/2024 BIOPOD WATER QUALITY FLOW CONTROL LOWEST PAVEMENT SUBBASIN COLLEC11ON VAULT FOR ENHANCED WQ STRUCTUREA RNISHED GRADE POINT AT PRESEl7LING AND PHOSPHOROUS CONTROLA ELEV.=419.25A AND OIL CONTROL TYPE 2 CATCH BASINS OUTFALL TO MS4 IE=412.50 INLET TO BIPOD IE=414.70 ARCH —TANK DETENTION SYS TOP=417.25 INLET & OUTLET IE=414.75 Civil Engineering and Consulting 2255 Squak Mountain Loop SW Issaquah, Washington 98027 (425) 864-8246 2.5—FT CHAMBER BOTTOM ELEV. = 414.75 EXCAVATION BOTTOM ELEV. = 414.25 DIAMETER AND DEPTH VARY FIGURE 9 STORMWATER MANAGEMENT SYSTEM SCHEMATIC DIAGRAM 212TH STREET REDEVELOPMENT 7509 212TH STREET SOUTHWEST EDMONDS, WASHINGTON CEKO PN:22017.01 DATE: 07/31 /2024 ccit-o APPENDIX A SITE AREAS SUMMARY TECHNICAL INFORMATION REPORT 212t" Street Site Redevelopment Edmonds, Washington CEKO PN: 22017.01 CAC EKO\ProjectslActive122017.01-Glacier-Headquarters\Engineering\TIR\2024-07-Stormwater-TI R.docx 4UiU—/1CO, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com cci1Co CEKO PN: 22017.01 Project Name: Glacier 212th Street Redevelopment Subject: Stormwater Site Area Calculations Prepared By: CPK Date: 7/31/2024 SITE AREAS SUMMARY References: 1 2019 Stormwater Management Manual for Western Washington 2019-SW M M W W 2 2022 Edmonds Storm water Addendum 2022 ESA 3 Civil Plans CN.NN 4 Western Washington Hydrology Model2012 WWHM2012 Total Sub -Basin Areas Total On -Site Areas = 37,827 SF or 0.86839 Acres Tota I Off -Site Areas = 616 SF or 0.01414 Acres Total Project Site Area = 38,443 SF or 0.88253 Acres Total Pre -Developed Sub -Basin Areas C Forest (flat) = 33,836 SF or 0.77677 Acres C Forest (mod) = 4,607 SF or 0.10576 Acres C Forest (steep) = 0 SF or 0.00000 Acres C Pasture (flat) = 0 SF or 0.00000 Acres C Pasture (mod) = 0 SF or 0.00000 Acres C Pasture (steep) = 0 SF or 0.00000 Acres Total 38,443 SF or 0.88253 Acres check OK Total Existing Sub -Basin Areas C Forest (flat) = 4,248 SF or 0.09752 Acres C Forest (mod) = 0 SF or 0.00000 Acres C Forest (steep) = 0 SF or 0.00000 Acres C Pasture (flat) = 0 SF or 0.00000 Acres C Pasture (mod) = 0 SF or 0.00000 Acres C Pasture (steep) = 0 SF or 0.00000 Acres C Lawn (flat) = 22,505 SF or 0.51664 Acres C Lawn (mod) = 0 SF or 0.00000 Acres C Lawn (steep) = 0 SF or 0.00000 Acres Roads (flat) = 0 SF or 0.00000 Acres Roads (mod) = 0 SF or 0.00000 Acres Roads (steep) = 0 SF or 0.00000 Acres Roof Tops (flat) = 2,571 SF or 0.05902 Acres Driveways (flat) = 8,503 SF or 0.19520 Acres Driveways (mod) = 0 SF or 0.00000 Acres Driveways (steep) = 0 SF or 0.00000 Acres Sidewalks (flat) = 616 SF or 0.01414 Acres Sidewalks (mod) = 0 SF or 0.00000 Acres Sidewalks (steep) = 0 SF or 0.00000 Acres Parking (flat) = 0 SF or 0.00000 Acres Parking (mod) = 0 SF or 0.00000 Acres Parking (steep) = 0 SF or 0.00000 Acres Pond = 0 SF or 0.00000 Acres Porous Pavement = 0 SF or 0.00000 Acres Total check Total On -Property Impervious Area = 38,443 SF or 0.88253 Acres OK 11,074 SF or 0.25422 Acres Page 1 of 5 cci1Co CEKO PN: 22017.01 Project Name: Glacier 212th Street Redevelopment Subject: Stormwater Site Area Calculations Prepared By: CPK Date: 7/31/2024 SITE AREAS SUMMARY References: 1 2019 Stormwater Management Manual for Western Washington 2019-SW M M W W 2 2022 Edmonds Storm water Addendum 2022 ESA 3 Civil Plans CN.NN 4 Western Washington Hydrology Model2012 WWHM2012 Total Proposed Developed Sub -Basin Areas C Forest (flat) = 4,248 SF or 0.09752 Acres C Forest (mod) = 0 SF or 0.00000 Acres C Forest (steep) = 0 SF or 0.00000 Acres C Pasture (flat) = 0 SF or 0.00000 Acres C Pasture (mod) = 0 SF or 0.00000 Acres C Pasture (steep) = 0 SF or 0.00000 Acres C Lawn (flat) = 7,308 SF or 0.16777 Acres C Lawn (mod) = 0 SF or 0.00000 Acres C Lawn (steep) = 0 SF or 0.00000 Acres Roads (flat) = 0 SF or 0.00000 Acres Roads (flat, offsite) = 0 SF or 0.00000 Acres Roads (mod) = 0 SF or 0.00000 Acres Roads (steep) = 0 SF or 0.00000 Acres Roof Tops (flat) = 7,276 SF or 0.16703 Acres Driveways (flat) = 18,995 SF or 0.43607 Acres Driveways (mod) = 0 SF or 0.00000 Acres Driveway (mod, bypass) = 0 SF or 0.00000 Acres Driveways (steep) = 0 SF or 0.00000 Acres Sidewalks (flat) = 616 SF or 0.01414 Acres Sidewalks (mod) = 0 SF or 0.00000 Acres Sidewalks (steep) = 0 SF or 0.00000 Acres Parking (flat) = 0 SF or 0.00000 Acres Parking (mod) = 0 SF or 0.00000 Acres Parking (steep) = 0 SF or 0.00000 Acres Pond = 0 SF or 0.00000 Acres Porous Pavement = 0 SF or 0.00000 Acres Total check Total On -Property Impervious Area = 38,443 SF or 0.88253 Acres OK 26,271 SF or 0.60310 Acres Page 2 of 5 CC/1rO CEKO PN: 22017.01 Subject: Stormwater Site Area Calculations Prepared By: CPK References: Project Name: Glacier 212th Street Redevelopment SITE AREAS SUMMARIES WITH TREE CREDITS Date: 7/31/2024 1 2019 Stormwater Management Manual for Western Washington 2019-SWMMWW 2 2022 Edmonds Storm water Addendum 2022 ESA 3 Civil Plans CN.NN 4 Western Washington Hydrology Model 2012 WWHM2012 Proposed Developed Sub -Basin Areas (Pre -Tree Credits) Land Cover Type Area C Forest (flat) = 4,248 SF or 0.09752 Acres C Forest (mod) = 0 SF or 0.00000 Acres C Forest (steep) = 0 SF or 0.00000 Acres C Pasture (flat) = 0 SF or 0.00000 Acres C Pasture (mod) = 0 SF or 0.00000 Acres C Pasture (steep) = 0 SF or 0.00000 Acres C Lawn (flat) = 7,308 SF or 0.16777 Acres C Lawn (mod) = 0 SF or 0.00000 Acres C Lawn (steep) = 0 SF or 0.00000 Acres Roads (flat) = 0 SF or 0.00000 Acres Roads (flat, offsite) = 0 SF or 0.00000 Acres Roads (mod) = 0 SF or 0.00000 Acres Roads (steep) = 0 SF or 0.00000 Acres Roof Tops (flat) = 7,276 SF or 0.16703 Acres Driveways (flat) = 18,995 SF or 0.43607 Acres Driveways (mod) = 0 SF or 0.00000 Acres Driveway (mod, bypass) = 0 SF or 0.00000 Acres Driveways (steep) = 0 SF or 0.00000 Acres Sidewalks (flat) = 616 SF or 0.01414 Acres Sidewalks (mod) = 0 SF or 0.00000 Acres Sidewalks (steep) = 0 SF or 0.00000 Acres Parking (flat) = 0 SF or 0.00000 Acres Parking (mod) = 0 SF or 0.00000 Acres Parking (steep) = 0 SF or 0.00000 Acres Pond = 0 SF or 0.00000 Acres Porous Pavement = 0 SF or 0.00000 Acres Total 38,443 SF or 0.88253 Acres Total On -Property Impervious Area = 26,271 SF or 0.60310 Acres Page 3 of 5 CC/1rO CEKO PN: 22017.01 Project Name: Glacier 212th Street Redevelopment Subject: Stormwater Site Area Calculations Prepared By: CPK Date: 7/31/2024 References: SITE AREAS SUMMARIES WITH TREE CREDITS 1 2019 Stormwater Management Manual for Western Washington 2019-SWMMWW 2 2022 Edmonds Storm water Addendum 2022 ESA 3 Civil Plans CN.NN 4 Western Washington Hydrology Model 2012 WWHM2012 Proposed Tree Retention Credits Dripline Percent Minimum Canopy Area Credit Credit Tree # Type (SF) N Area (SF) Credit 4 17" Fir 1017 20 100 203 SF or 0.00467 Acres 3 22" Fir 1017 20 100 203 SF or 0.00467 Acres 2 24" Fir 1256 20 100 251 SF or 0.00577 Acres 1 20" Fir 1017 20 100 203 SF or 0.00467 Acres 28 14" Fir 201 20 100 100 SF or 0.00230 Acres 34 23" Fir 1520 20 100 304 SF or 0.00698 Acres 44 17" Fir 1256 20 100 251 SF or 0.00577 Acres 45 10" Pine 314 20 100 100 SF or 0.00230 Acres 46 6" Madrona 113 10 50 50 SF or 0.00115 Acres 54 14 Fir 201 20 100 100 SF or 0.00230 Acres 59 21" Fir 1017 20 100 203 SF or 0.00467 Acres 68 20 Decid 452 10 50 50 SF or 0.00115 Acres 67 10" Hawthorn 314 10 50 50 SF or 0.00115 Acres Total 2,070 SF or 0.04752 Acres Proposed Newly Planted Tree Credits (On -Site) Canopy Area Tree Quantity Type (SF) Credit 11 Red Cedar 50 550 SF or 0.01263 Acres 9 Shore Pine 50 450 SF or 0.01033 Acres 2 Serbian Spruce 50 100 SF or 0.00230 Acres 4 Honey Locust 20 80 SF or 0.00184 Acres 5 Magnolia 20 100 SF or 0.00230 Acres Total 1,280 SF or 0.02938 Acres Total On -Site Credit 3,350 SF or 0.07691 Acres Proposed Newly Planted Tree Credits (Right -of -Way) Canopy Area Tree Quantity Type (SF) Credit 3 Street Tree 20 60 SF or 0.00138 Acres Total 60 SF or 0.00138 Acres Total Proposed Tree Credits Total 3,410 SF or 0.07828 Acres Page 4 of 5 CC/1rO CEKO PN: 22017.01 Project Name: Glacier 212th Street Redevelopment Subject: Stormwater Site Area Calculations Prepared By: CPK Date: 7/31/2024 References: SITE AREAS SUMMARIES WITH TREE CREDITS 1 2019 Stormwater Management Manual for Western Washington 2019-SWMMWW 2 2022 Edmonds Storm water Addendum 2022 ESA 3 Civil Plans CN.NN 4 Western Washington Hydrology Model 2012 WWHM2012 Proposed Developed Sub -Basin Areas (Corrected after Tree Credits) Land Cover Type Area C Forest (flat) = 4,248 SF or 0.09752 Acres C Forest (mod) = 0 SF or 0.00000 Acres C Forest (steep) = 0 SF or 0.00000 Acres C Pasture (flat) = 0 SF or 0.00000 Acres C Pasture (mod) = 0 SF or 0.00000 Acres C Pasture (steep) = 0 SF or 0.00000 Acres C Lawn (flat) = 7,308 SF or 0.16777 Acres C Lawn (mod) = 0 SF or 0.00000 Acres C Lawn (steep) = 0 SF or 0.00000 Acres Roads (flat) = 0 SF or 0.00000 Acres Roads (flat, offsite) = 0 SF or 0.00000 Acres Roads (mod) = 0 SF or 0.00000 Acres Roads (steep) = 0 SF or 0.00000 Acres Roof Tops (flat) = 7,276 SF or 0.16703 Acres Driveways (flat) = 15,645 SF or 0.35916 Acres Driveways (mod) = 0 SF or 0.00000 Acres Driveway (mod, bypass) = 0 SF or 0.00000 Acres Driveways (steep) = 0 SF or 0.00000 Acres Sidewalks (flat) = 556 SF or 0.01276 Acres Sidewalks (mod) = 0 SF or 0.00000 Acres Sidewalks (steep) = 0 SF or 0.00000 Acres Parking (flat) = 0 SF or 0.00000 Acres Parking (mod) = 0 SF or 0.00000 Acres Parking (steep) = 0 SF or 0.00000 Acres Pond = 0 SF or 0.00000 Acres Porous Pavement = 0 SF or 0.00000 Acres Total 35,033 SF or 0.80425 Acres Total On -Property Impervious Area = 22,921 SF or 0.52619 Acres Page 5 of 5 ccit-o APPENDIX B GEOTECHNICAL ENGINEERING INVESTIGATION REPORT TECHNICAL INFORMATION REPORT 212t" Street Site Redevelopment Edmonds, Washington CEKO PN: 22017.01 CAC EKO\ProjectslActive122017.01-Glacier-Headquarters\Engineering\TIR\2024-07-Stormwater-TI R.docx 4UiU—/1CO, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com GEOTECHNICAL ENGINEERING INVESTIGATION PROPOSED GLACIER OFFICES AND WAREHOUSE 7509 212TH STREET SW EDMONDS, WA 98026 PROJECT No. 092-22001 FEBRUARY 04, 2022 Prepared for: GLACIER ENVIRONMENTAL SERVICES, INC ATTN: LAUREN GOLEMBIEWSKI, PRESIDENT 7509 212TH STREET SW EDMONDS, WA 98026 Prepared by: KRAZAN & ASSOCIATES, INC. GEOTECHNICAL ENGINEERING DIVISION 4303 —198TH STREET SW LYNNWOOD, WASHINGTON 98036 (425) 485-5519 -Krazan & ASSOCIATES,INC. GEOTECHNICAL ENGINEERING • ENVIRONMENTAL ENGINEERING CONSTRUCTION TESTING & INSPECTION February 04, 2022 Glacier Environmental Services, Inc. P.O. Box 1097 Mukilteo, WA 98275 Attn: Ms. Lauren Golembiewski, President Email: Imiles@glacierenviro.com Tel: 425-268-9775 RE: GEOTECHNICAL ENGINEERING INVESTIGATION Proposed Glacier Offices and Warehouse 7509 212'' Street SW Edmonds, WA 98026 Dear Ms. Golembiewski, KA Project No. 092-22001 In accordance with your request, we have completed a Geotechnical Engineering Investigation for the referenced site. The results of our investigation are presented in the attached report. If you have any questions, or if we can be of further assistance, please do not hesitate to contact our office. Respectfully submitted, KRAZAN & ASSOCIATES, INC. Michael D. Rundquist, P.E. Senior Project Manager MDR IN, Offices Serving The Western United States 4303 —198t' Street SW • Lynnwood, Washington 98036 • (425) 485-5519 • Fax: (425) 485-6837 -I'('a7_ a1 & ASSOCIATES,INC. GEOTECHNICAL ENGINEERING • ENVIRONMENTAL ENGINEERING CONSTRUCTION TESTING & INSPECTION TABLE OF CONTENTS INTRODUCTION....................................................................................................................................................... 1 PROJECTDESCRIPTION........................................................................................................................................ 1 PURPOSEAND SCOPE............................................................................................................................................. 2 SITECONDITIONS................................................................................................................................................... 3 GEOLOGICSETTING.............................................................................................................................................. 3 FIELDINVESTIGATION......................................................................................................................................... 3 SOIL PROFILE AND SUBSURFACE CONDITIONS............................................................................................. 4 GROUNDWATER...................................................................................................................................................... 6 GEOLOGICHAZARDS............................................................................................................................................ 6 ErosionConcern/Hazard...................................................................................................................................... SeismicHazard................................................................................................................................................... CONCLUSIONS AND RECOMMENDATIONS...................................................................................................... 8 General........................................................................................................................................ SitePreparation............................................................................................................................ TemporaryExcavations................................................................................................................ StructuralFill............................................................................................................................... ShallowFoundations.................................................................................................................... Floor Slabs and Exterior Flatwork................................................................................................ Lateral Earth Pressures and Retaining Walls................................................................................. Stormwater Management.............................................................................................................. OrganicContent........................................................................................................................... CationExchange Capacity............................................................................................................ Erosion and Sediment Control...................................................................................................... Groundwater Influence on Structures/ Construction...................................................................... Drainage and Landscaping........................................................................................................... UtilityTrench Backfill................................................................................................................. Testingand Inspection.................................................................................................................. ............................. 8 ............................. 9 ........................... 10 ........................... 11 ........................... 11 ........................... 13 ........................... 13 ........................... 14 ........................... 16 ........................... 16 ........................... 17 ........................... 18 ........................... 18 ........................... 18 ........................... 19 LIMITATIONS......................................................................................................................................................... 20 VICINITYMAP.............................................................................................................................. Figure 1 SITEPLAN...................................................................................................................................... Figure 2 FIELD INVESTIGATION AND LABORATORY TESTING ................................................ Appendix A EARTHWORK SPECIFICATIONS........................................................................................ Appendix B PAVEMENT SPECIFICATIONS............................................................................................ Appendix C Offices Serving The Western United States 4303 — 19811 Street SW 9 Lynnwood, Washington 98036 9 (425) 485-5519 9 Fax: (425) 485-6837 �Irazan & ASSOCIATES,INC. GEOTECHNICAL ENGINEERING • ENVIRONMENTAL ENGINEERING CONSTRUCTION TESTING & INSPECTION February 04, 2022 KA Project No. 092-22001 GEOTECHNICAL ENGINEERING INVESTIGATION PROPOSED GLACIER OFFICES AND WAREHOUSE 7509 212TH STREET SW EDMONDS, WASHINGTON 98026 INTRODUCTION This report presents the results of our geotechnical engineering investigation for the commercial project located at 7509 212th Street SW in Edmonds, Washington, as shown on the Vicinity Map in Figure 1. Discussions regarding site conditions are presented in this report, together with conclusions and recommendations pertaining to site preparation, excavations, structural fill, foundations, drainage and landscaping, and erosion control. We have been requested to conduct a geotechnical investigation regarding foundation support and stormwater infiltration testing to aid in project design. A site plan showing the approximate exploratory test pit and infiltration test locations is presented in Figure 2 following the text of this report. Appendix A includes a description of the field investigation and the soil logs. Appendix B contains a guide to aid in the development of earthwork specifications. Pavement design guidelines are presented in Appendix C. The recommendations in the main text of the report have precedence over the more general specifications in the appendices. PROJECT DESCRIPTION The site is roughly rectangular in shape and is located on the north side of 212th Street SW, approximately 250 feet east of the intersection with 76th Avenue W. The property covers an area of approximately 0.87 acres. A commercial property borders the site to the west. Residential properties border the site to the north and east. 212th Street SW borders the site to the south. A residence, accessory dwelling units and small storage barn currently occupy the property. Minimal grading is anticipated for the demolition of existing structures and the construction of the new facilities. The proposed development will include design and construction of a new two-story office building and a pre-fab metal warehouse, along with associated utilities, pavement, and landscape areas. A bio-retention swale along the eastern edge of the property is under consideration for this project. Offices Serving The Western United States 4303 — 198"' Street SW 9 Lynnwood, Washington 98036 9 (425) 485-5519 9 Fax: (425) 485-6837 Krazan & Associates, Inc. PURPOSE AND SCOPE KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 2 This investigation was conducted to evaluate the subsurface soil and groundwater conditions at the site, to develop geotechnical engineering recommendations for use in design of specific construction elements, and to provide criteria for earthwork construction. Our services were performed in general accordance with our proposal for this project, dated January 11, 2022 (Proposal Number G22018WAL) and included the following: • Explore the subsurface soil conditions with test pit excavations in the project area. Soil samples were collected for laboratory testing. • Prepare a site plan showing the test pit locations; • Prepare test pit logs including soil stratification and classification, and groundwater levels where applicable; • Provide recommendations for foundation design including foundation type, allowable foundation bearing pressure, anticipated settlements (both total and differential), coefficient of horizontal friction, and frost penetration depth; • Provide recommendations for retaining wall design including lateral earth pressures (active and passive); • Provide recommendations for seismic design considerations, including site coefficient and ground acceleration based on the 2018 International Building Code (IBC); • Provide soil parameters for the design of slab -on -grade floors including recommendations for placement of capillary break material and vapor barrier below the slabs; • Discuss construction and excavation considerations, topsoil/unsuitable soil stripping depth, identification of potentially problematic soils or groundwater conditions, and depth of over - excavation if required; • Provide opinions on the feasibility of stormwater infiltration on this site, and design infiltration rates where feasible; • Provide recommendations for structural fill materials, placement, and compaction; • Provide recommendations for temporary excavations; • Provide recommendations for site drainage and erosion control; and • Provide recommendations for standard and heavy-duty pavement design. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. SITE CONDITIONS KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 3 The project site is located in a mixed residential and commercial neighborhood about three blocks west of Highway 99. The site slopes gently down to the northwest and to the south from a high point in the central portion of the property. The site is vegetated with trees, bushes and lawn areas. There are asphalt and gravel surfaced driveway and parking areas in the southwest portion of the property. Small rockeries, about two to four feet in height, face the south and west edges of the front yard. GEOLOGIC SETTING We referred to the "Geologic Map of the Edmonds East and Part of the Edmonds West Quadrangles, Washington," by James P. Minard (1983) during our project research. The geologic map indicates that the site vicinity is underlain by Quaternary Vashon glacial till (Qgt,,). Quaternary Advance outwash (Qva) is also mapped nearby. Glacial till typically consists of a very compact, unsorted mixture of clay, silt, sand, gravel, cobbles and boulders. Advance outwash generally consists of poorly to moderated sorted, dense to very dense sand and gravel. FIELD INVESTIGATION Four test pit explorations and three infiltration test pits were completed to evaluate the subsurface soil and groundwater conditions within the property. The test pits were completed on January 24, 2022. The explorations were conducted using a client -provided excavator. The test pits extended to depths ranging from approximately 4.0 feet to about 11.0 feet below the existing ground surface. A geotechnical representative from Krazan and Associates, Inc. was present during the test pit explorations, examined the soil conditions encountered, obtained samples of the different soil types, and maintained logs of the explorations. The approximate locations of the explorations are shown on the Site Plan in Figure 2. Representative samples of the subsurface soils encountered in the geotechnical explorations at the project site were collected and sealed in plastic bags for transport to our laboratory for further observation and testing. The soils encountered in the explorations were continuously examined and visually classified in general accordance with the Unified Soil Classification System (USCS). Although our explorations did not encounter obstructions, there is the potential for obstructions such as debris, cobbles or boulders to be encountered during excavation in unexplored areas of the property. For additional information about the soils encountered, please refer to the logs of the explorations in Appendix A. Small -Scale Pilot Infiltration Test (PIT): Three (3) infiltration test pits, designated INF-1, INF-2 and INF-3, were excavated to depths between 6.0 and 11.0 feet below adjacent grade. The locations of the test pits/infiltration tests are shown on the Site Plan in Figure 2. The PITs were performed in accordance Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 4 with Volume III, Chapter 3 of the Department of Ecology (DOE) 2019 Stormwater Management Manual for Western Washington (SMMWW). The PITS were also performed in accordance with the Edmonds Stormwater Addendum (updated June 2017) Checklist 4: Methods for Determining Infiltration Rates. The infiltration tests were performed at depths of approximately 2.0 and 9.0 feet below the existing ground surface (bgs) at the time of the testing, and are noted on the attached test pit logs. The exposed test areas for each of the PITs were approximately 24 square feet for INF-1, 20 square feet for INF-2, and 15 square feet for INF-3. The infiltration tests included a pre-soak period, followed by a steady- state infiltration rate test, and then falling head infiltration rate testing. Following the infiltration tests, the test pits were advanced to depths of 6.0 and 11.0 feet bgs to examine the soil conditions below the level where the test was performed. A field engineer from Krazan and Associates was present during the exploration and testing, examined the soils and geologic conditions encountered, obtained samples of the different soil types, documented results of the infiltration testing and maintained logs of the soils exposed in the test pits. Representative samples of the subsurface soils encountered in the test pits were collected and sealed in plastic bags. These samples were transported to our laboratory for further examination and testing. The soils encountered in the exploratory test pits were continuously examined and visually classified in accordance with the Unified Soil Classification System (USCS). SOIL PROFILE AND SUBSURFACE CONDITIONS Four test pits and three infiltration test pits were excavated at the property. Brief descriptions of the subsurface conditions exposed in the test pits are included in the paragraphs below. Test Pit 1 (TP-1) was located in the northwest portion of the property. TP-1 exposed a surficial layer of organic topsoil extending to a depth of approximately 0.5 foot. Below the topsoil, the test pit exposed loose to medium dense, brown silty sand with gravel and trace organics to a depth of about 3.0 feet. We interpreted the brown silty sand with gravel and trace organics to be weathered soils. Underlying the weathered soil, TP-1 exposed dense, gray silty sand with gravel to the depth explored of approximately 4.0 feet below grade. We interpreted the gray silty sand with gravel to be native glacial soil. Test Pit 2 (TP-2) was located in the north -central portion of the property. TP-2 exposed a surficial layer of organic topsoil and forest duff extending to a depth of approximately 2.0 feet. Below the topsoil and forest duff, the test pit exposed loose to medium dense, brown silty sand with gravel and trace organics to a depth of about 4.0 feet. We interpreted the brown silty sand with gravel and trace organics to be weathered soils. Underlying the weathered soil, TP-2 exposed dense, gray silty sand with gravel to the depth explored of approximately 4.5 feet below grade. We interpreted the gray silty sand with gravel to be native glacial soil. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 5 Test Pit 3 (TP-3) was located north of the residence, in the east -central portion of the property. TP-3 exposed a surficial layer of organic topsoil extending to a depth of approximately 0.5 foot. Below the topsoil, the test pit exposed loose to medium dense, brown silty sand with gravel and trace organics to a depth of about 3.0 feet. We interpreted the brown silty sand with gravel and trace organics to be weathered soils. Underlying the weathered soil, TP-3 exposed dense, gray silty sand with gravel to the depth explored of approximately 4.0 feet below grade. We interpreted the gray silty sand with gravel to be native glacial soil. Test Pit 4 (TP-4) was located southeast of the residence, in the southeast portion of the property. TP-4 exposed a surficial layer of organic topsoil extending to a depth of approximately 0.5 foot. Below the topsoil, the test pit exposed loose to medium dense, brown silty sand with gravel and trace organics to a depth of about 3.0 feet. We interpreted the brown silty sand with gravel and trace organics to be weathered soils. Underlying the weathered soil, TP-4 exposed dense, gray silty sand with gravel to the depth explored of approximately 4.0 feet below grade. We interpreted the gray silty sand with gravel to be native glacial soil. Infiltration Test Pit 1 (INF-1) was located west of the residence, in the south-central portion of the property. INF-1 exposed a surficial layer of organic topsoil extending to a depth of approximately 0.5 foot. Below the topsoil, the test pit exposed loose gray silty sand with gravel to a depth of about 2.0 feet. We interpreted the gray silty sand with gravel to be undocumented fill. Below the undocumented fill, the test pit exposed loose to medium dense, brown silty sand with gravel and trace organics to a depth of about 4.0 feet. We interpreted the brown silty sand with gravel and trace organics to be weathered soils. Underlying the weathered soil, INF-1 exposed dense, gray silty sand with gravel to the depth explored of approximately 11.0 feet below grade. We interpreted the gray silty sand with gravel to be native glacial soil. Infiltration Test Pit 2 (INF-2) was located east of the western ADU, in the north -central portion of the property. INF-2 exposed a surficial layer of organic topsoil extending to a depth of approximately 0.5 foot. Below the topsoil, the test pit exposed loose to medium dense, brown silty sand with gravel and trace organics to a depth of about 2.5 feet. We interpreted the brown silty sand with gravel and trace organics to be weathered soils. Underlying the weathered soil, INF-2 exposed dense, olive -brown to gray silty sand with gravel to the depth explored of approximately 11.0 feet below grade. We interpreted the gray silty sand with gravel to be native glacial soil. Infiltration Test Pit 3 (INF-3) was located north of the eastern ADU, in the northeast portion of the property. INF-3 exposed a surficial layer of organic topsoil extending to a depth of approximately 0.5 foot. Below the topsoil, the test pit exposed loose to medium dense, dark yellowish -brown sand with silt, gravel and trace organics to a depth of about 3.0 feet. We interpreted the brown silty sand with gravel and trace organics to be weathered soils. Underlying the weathered soil, INF-3 exposed dense, Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 6 gray silty sand with gravel to the depth explored of approximately 6.0 feet below grade. We interpreted the gray silty sand with gravel to be native glacial soil. For additional information about the soils encountered, please refer to the soil logs in Appendix A. GROUNDWATER The test pits were observed for the presence of groundwater during the test pit explorations. Soil conditions were moist. Groundwater seepage was not observed in the test pit explorations at the time of our subsurface investigation. However, it is our opinion that perched groundwater could occur on this property, especially during and after prolonged periods of wet weather. Perched water occurs when surface water infiltrates through less dense, more permeable soils and accumulates on top of a relatively low permeability soil layer. Perched water does not represent a regional groundwater "table" within the upper soil horizons. Perched water tends to vary spatially and is dependent upon the amount of rainfall. We would expect the amount of perched water to decrease during drier times of the year and increase during wetter periods. It should be recognized that groundwater elevations may fluctuate with time. The groundwater level will be dependent upon seasonal precipitation, irrigation, as well as other factors. Therefore, groundwater levels at the time of the field investigation may be different from those encountered during the construction phase of the project. The evaluation of such factors is beyond the scope of this report. GEOLOGIC HAZARDS Erosion Concern/Hazard The Natural Resources Conservation Service (MRCS) map for Snohomish County includes information regarding the erosion hazard for the site vicinity. The soil in project area is mapped as Alderwood- Urban land complex, 2 to 8 percent slopes. These soils are rated as having a moderate hazard for soil erosion when vegetation is removed. It has been our experience that the potential for soil erosion can be minimized through landscaping and surface water runoff control. Typically, erosion of exposed soils will be most noticeable during periods of rainfall and may be controlled by the use of temporary erosion control measures, such as silt fences, hay bales, mulching, control ditches or diversion trenching, and contour furrowing. Erosion control measures should be in place before the onset of wet weather. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. Seismic Hazard KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 7 The 2018 International Building Code (IBC), Section 1613.2.2, refers to Chapter 20 of ASCE 7-16 for Site Class Definitions. It is our opinion that the overall soil profile corresponds to Site Class C defined by Table 20.3-1 "Site Class Definitions," according to the ASCE 7-16 Standard. Site Class C applies to a "very dense soils and soft rock" profile. The seismic site class is based on a soil profile extending to a depth of 100 feet. The soil explorations on this site extended to a maximum depth of approximately 11.0 feet and this seismic site class designation is based on the assumption that dense to very dense conditions continue below the depth explored. We referred to the Applied Technology Council (ATC) website and 2018 IBC to obtain values for Ss, Stirs, SDs, SI, Smi, SDI, F., F,, and T. The ATC website utilizes the most updated published data on seismic conditions from the United States Geological Survey. The seismic design parameters for this site are presented in the following table: Seismic Design Parameters (Reference: 2018 IBC Section 1613.2.2, ASCE7-16, and ATC) Seismic Item Value Site Coefficient Fa 1.200 S, 1.286 SMs 1.543 SDs 1.029 Site Coefficient Fv 1.500 S1 0.453 SMI 0.679 SDI 0.453 Additional seismic considerations include liquefaction potential and amplification of ground motion by soft soil deposits. The liquefaction potential is highest for loose sand with a high groundwater table. The medium dense to dense native soils interpreted to underlie the site are considered to have a low potential for liquefaction and amplification of ground motion. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. CONCLUSIONS AND RECOMMENDATIONS General KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 8 It is our opinion from a geotechnical standpoint that the site is compatible with the proposed commercial development, provided that our recommendations are incorporated into project plans and are implemented during construction. Summary of Subsurface Conditions: Our explorations generally encountered a near surface layer of loose organic soil and undocumented fill extending to depths of about 0.5 to 2.0 feet. Beneath the surficial soils, the test pits generally exposed loose to medium dense native weathered soils, consisting of silty sand with gravel, to depths of 2.5 to 4.0 feet. Beneath the weathered horizon, the test pits exposed dense to very dense native glacial till (hardpan) consisting of silty sand with gravel. Groundwater seepage was not observed at the time of our subsurface investigation. The dense/hard soils are interpreted to be native glacially consolidated deposits, and typically have a relatively high capacity for foundation support. The undocumented fill soils are not considered suitable for foundation support. Groundwater seepage was not encountered during our field investigation. However, perched groundwater could develop on this site during or after periods of wet weather. Care should be taken to protect foundation subgrades from disturbance if groundwater or wet soils are encountered. Difficult Excavation: Dense to very dense glacial soils, which may include cobbles and boulders, are interpreted to underlie the site. We anticipate that future excavations in the glacial soils could be difficult. It might be prudent to provide contingencies in the project schedule and budget in case excavation difficulties arise during earthwork construction. Foundations: The dense glacial soils underlying the site should provide adequate load bearing capacity for the proposed commercial structures. Detailed foundation support recommendations, including a recommended allowable load bearing pressure, are included in the Foundations section of this report. The installation of foundation drains is recommended for this project. Stormwater Infiltration: The dense to very dense glacial till soil (hardpan) encountered in the test pits at this site are not considered suitable for the use of infiltration techniques for stormwater management. There is some potential for slight amounts infiltration as discussed in the Stormwater Management section of this report. Moisture Sensitive Soils: The soils encountered in our explorations on site are considered to be highly moisture -sensitive. Silty soils are typically easily disturbed and are difficult or impossible to compact in wet conditions. It will be necessary to protect exposed subgrade soil with a layer of crushed rock if Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 9 construction occurs during wet weather. The non -organic on -site soils could be used as structural fill material, provided the moisture content is near optimum and the soil could be suitably compacted to project specifications. This will depend on the moisture content of the soils at the time of construction. Krazan and Associates is available on request to evaluate the suitability of the on -site soils for use as structural fill material at the time of construction. Site Preparation General site clearing should include removal of existing structures; vegetation; trees and associated root systems; wood; abandoned structures and utilities; rubble; and rubbish. Site stripping should extend until all organics in excess of 3 percent by volume are removed. These materials will not be suitable for use as structural fill. However, stripped topsoil may be stockpiled and re -used in landscape or non- structural areas. After stripping operations, the construction areas should be inspected to identify any soft/loose areas. Any remaining soft/loose soils should be excavated to expose medium dense or firmer native soils. The resulting excavations should be filled with approved structural fill. Structural fill material should be within f 2 percent of the optimum moisture content, and the soils should be compacted to a minimum of 95 percent of the maximum dry density as determined by ASTM Test Method D 1557. During wet weather conditions, subgrade stability problems and grading difficulties may develop due to excess moisture, disturbance of sensitive soils and/or the presence of perched groundwater. Construction during the extended periods of wet weather could result in the need to remove wet disturbed soils if they cannot be suitably compacted due to elevated moisture contents. The on -site soils have significant silt content and are considered to be moisture sensitive, and can be easily disturbed when wet. If overexcavation is necessary to remove wet disturbed soil, it should be confirmed through continuous monitoring and testing by a qualified geotechnical engineer or geologist. Soils that have become unstable may require drying to near their optimal moisture content before compaction is feasible. Selective drying may be accomplished by scarifying or windrowing surficial material during extended periods of dry, warm weather (typically during the summer months). If the soils cannot be dried back to a workable moisture condition, remedial measures may be required. General project site winterization should consist of the placement of aggregate base and the protection of exposed soils during the construction phase. It should be understood that even if Best Management Practices (BMPs) are implemented and followed for wintertime soil protection there is a significant chance that mitigation of disturbed moisture sensitive soils will still be required. Any buried structures encountered during construction should be properly removed and backfilled. Excavations, depressions, or soft and pliant areas extending below the planned finish subgrade levels Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 10 should be excavated to expose firm undisturbed soil, and backfilled with structural fill. In general, any septic tanks, underground storage tanks, debris pits, cesspools, or similar structures should be completely removed from the area of the planned addition. Concrete footings should be removed to an equivalent depth of at least 3 feet below proposed footing elevations or as recommended by the geotechnical engineer. The resulting excavations should be backfilled with structural fill. A representative of our firm should be present during all site clearing and grading operations to observe, test and evaluate earthwork construction. This testing and observation are integral parts of our service, as acceptance of earthwork construction is dependent upon compaction and stability of the material. The geotechnical engineer may reject any material that does not meet compaction and stability requirements. Further recommendations, contained in this report, are predicated upon the assumption that earthwork construction will conform to the recommendations set forth in this section and in the Structural Fill section. Temporary Excavations The on -site soils may have variable cohesion strengths, therefore the safe angles to which these materials may be cut for temporary excavations is limited, as the soils may be prone to caving and slope failures in temporary excavations. Temporary excavations in the loose to medium dense soils should be no steeper than 1H:1V (Horizontal to Vertical). Depending on the groundwater conditions, flatter inclinations may be necessary. Temporary shoring may also be necessary if excavation to stable inclinations is not feasible due to the proximity to structures or property lines. We should evaluate the excavations at the time of construction. All temporary cuts should be in accordance with Washington Administrative Code (WAC) Part N, Excavation, Trenching, and Shoring. The temporary slope cuts should be visually inspected daily by a qualified person during construction work activities and the results of the inspections should be included in daily reports. The contractor is responsible for maintaining the stability of the temporary cut slopes and minimizing slope erosion during construction. The temporary cut slopes should be covered with plastic sheeting to help minimize erosion during wet weather and the slopes should be closely monitored until the permanent retaining systems are complete. Materials should not be stored and equipment operated within 10 feet of the top of any temporary cut slope. A Krazan & Associates geologist or geotechnical engineer should observe, at least periodically, the temporary cut slopes during the excavation work. The reason for this is that all soil conditions may not be fully delineated by the limited sampling of the site from the geotechnical explorations. In the case of temporary slope cuts, the existing soil conditions may not be fully revealed until the excavation work exposes the soil. Typically, as excavation work progresses the maximum inclination of the temporary slope will need to be evaluated by the geotechnical engineer so that supplemental recommendations can Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 11 be made. Soil and groundwater conditions can be highly variable. Scheduling for soil work will need to be adjustable, to deal with unanticipated conditions, so that the project can proceed smoothly and required deadlines can be met. If any variations or undesirable conditions are encountered during construction, Krazan & Associates should be notified so that supplemental recommendations can be made. Structural Fill Fill placed beneath foundations, pavement, or other settlement -sensitive structures should be placed as structural fill. Structural fill, by definition, is placed in accordance with prescribed methods and standards, and is monitored by an experienced geotechnical professional. Field monitoring procedures would include the performance of a representative number of in -place density tests to document the attainment of the desired degree of relative compaction. The area to receive the fill should be suitably prepared as described in the Site Preparation subsection of this report prior to beginning fill placement. Typically, all weather imported structural fill material should consist of well -graded gravel or sand and gravel mixture with a maximum grain size of 3 inches and less than 5 percent fines (material passing the U.S. Standard No. 200 Sieve). All structural fill material should be submitted for approval to the geotechnical engineer at least 48 hours prior to delivery to the site. Fill soils should be placed in horizontal lifts not exceeding 8 inches in thickness prior to compaction, moisture -conditioned as necessary, (moisture content of soil shall not vary by more than f2 percent of optimum moisture) and the material should be compacted to at least 95 percent of the maximum dry density based on ASTM Test Method D1557. In -place density tests should be performed on all structural fill to document proper moisture content and adequate compaction. Additional lifts should not be placed if the previous lift did not meet the compaction requirements or if soil conditions are not considered stable. Foundations Conventional shallow spread footings supported on dense native glacial soils, or on structural fill extending to the dense native glacial soils, may be designed using an allowable bearing pressure of 3,500 pounds per square foot (psf) for dead plus live loads. This value may be increased by one third for short duration loads such as wind or seismic loading. A representative of Krazan and Associates should visit the site during construction to evaluate the foundation bearing soil, evaluate structural fill subgrade preparation, and monitor structural fill placement. If loose soils or undocumented fill are exposed in the foundation subgrade, the removal of undocumented fill and placement of structural fill should extend horizontally beyond the outside edges of the footings by a distance equal to half the thickness of the structural fill layer to be placed beneath Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 12 the footing. Based on our soil explorations, we interpret the dense, native bearing soils at this site to be approximately 2.5 to 4.0 feet below the current grade. However, thicker layers of loose/soft soils, organics, debris, or undocumented fill could be encountered in unexplored areas of the site. Foundations should have a minimum embedment depth of 18 inches below pad subgrade (soil grade) or adjacent exterior grade, whichever is lower. Footing widths should be based on the anticipated loads and allowable soil bearing pressure. Footings should have a minimum width of at least 12 inches regardless of load. All loose or disturbed soil should be removed from the foundation excavation prior to placing concrete. Water should not be allowed to collect in the foundation excavations. All-weather structural fill material should consist of well -graded gravel, or sand and gravel mixture, with a maximum grain size of 3 inches and less than 5 percent fines (material passing the U.S. Standard No. 200 Sieve). All structural fill material should be submitted for approval to the geotechnical engineer at least 48 hours prior to delivery to the site. Footing excavations should be inspected to verify that the foundations will be supported on suitable soil prior to the construction of footing forms. For foundations constructed as recommended, the total settlement is not expected to exceed one -inch. Differential settlement, along a 20-foot exterior wall footing, or between adjoining column footings should be less than '/2-inch. Most settlement is expected to occur during construction, as the loads are applied. However, additional post -construction settlement may occur if the foundation soils are flooded or saturated. It should be noted that the risk of liquefaction is considered low, given the composition and density of the native, on site soils. Seasonal rainfall, water run-off, and the normal practice of watering trees and landscaping areas around the proposed structures, should not be permitted to flood and/or saturate foundation subgrade soils. To prevent the buildup of water within the footing areas, continuous footing drains (with cleanouts) should be provided at the bases of the footings. The footing drains should consist of a minimum 4-inch diameter rigid perforated PVC pipe, sloped to drain, with perforations placed near the bottom and enveloped by one -inch sized washed rock in all directions and wrapped with filter fabric to reduce the migration of silt and clay into the drain. Resistance to lateral footing displacement can be computed using an allowable friction factor of 0.40 acting between the bases of foundations and the supporting subgrade. Lateral resistance for footings can also be developed using an allowable equivalent fluid passive pressure of 300 pounds per cubic foot (pcf) acting against the appropriate vertical footing faces (neglecting the upper 12 inches of soil). The allowable friction factor and allowable equivalent fluid passive pressure values include a factor of safety of 1.5. The frictional and passive resistance of the soil may be combined without reduction in determining the total lateral resistance. A 1/3 increase in the above values may be used for short duration, wind and seismic loads. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. Floor Slabs and Exterior Flatwork KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 13 For building floor slab subgrades prepared in accordance with the recommendations presented in the Site Preparation section of this report, floor slabs may be designed using a modulus of subgrade reaction value of k = 200 pounds per cubic inch (pci) for slabs supported on medium dense or firmer native soils or on structural fill extending to medium dense or firmer native soil. In areas where it is desired to reduce floor dampness, such as areas covered with moisture sensitive floor coverings, we recommend that concrete slab -on -grade floors be underlain by a water vapor retarder system. The water vapor retarder should consist of a vapor retarder sheeting underlain by a minimum of 4-inches of compacted clean (less than 5 percent passing the U.S. Standard No. 200 Sieve), open -graded coarse rock of 3/4-inch maximum size. The vapor retarder sheeting should be protected from puncture damage. It is recommended that the utility trenches within the structures be compacted, as specified in our report, to minimize the transmission of moisture through the utility trench backfill. Special attention to the immediate drainage and irrigation around the buildings is recommended. Positive drainage should be established away from the structures and should be maintained throughout the lives of the structures. Water should not be allowed to collect adjacent to the structures. Over -irrigation within landscaped areas adjacent to the structures should not be performed. In addition, ventilation of the structures may be prudent to reduce the accumulation of interior moisture. LATERAL EARTH PRESSURES AND RETAINING WALLS We have developed criteria for the design of retaining or below grade walls. Our design parameters are based on retention of the in -place soils or structural fill. The parameters are also based on level, well - drained wall backfill conditions. Walls may be designed as "restrained" retaining walls based on "at - rest" earth pressures, plus any surcharge on top of the walls as described below, if the walls are braced to restrain movement and/or movement is not acceptable. Unrestrained walls may be designed based on "active" earth pressure, if the walls are not part of the buildings and some movement of the retaining walls is acceptable. Acceptable lateral movement equal to at least 0.2 percent of the wall height would warrant the use of "active" earth pressure values for design. The following table, titled Wall Design Criteria, presents the recommended soil related design parameters for retaining walls with well -drained level backfill. Wall Design Criteria "At -rest" Conditions (Lateral Earth Pressure) 55 pcf (Equivalent Fluid Density) (Triangular Distribution) Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 14 "Active" Conditions (Lateral Earth Pressure) 35 pcf (Equivalent Fluid Density) (Triangular Distribution Seismic Increase for "Active" Conditions 7 psf x H (Uniform Distribution) (Lateral Earth Pressure) Where H is the height of the wall in feet Passive Earth Pressure on Low Side of Wall Neglect upper one -foot, then 300 pcf (includes factor of safety of 1.5) (Equivalent Fluid Density) Soil -Footing Coefficient of Sliding Friction 0.4 includes factor of safety of 1.5 The stated lateral earth pressures do not include the effects of hydrostatic pressure generated by water accumulation behind the retaining walls or loads imposed by construction equipment, foundations or roadways adjacent to the wall (surcharge loads). To minimize the lateral earth pressure and prevent the buildup of water pressure against the walls, continuous footing drains (with cleanouts) should be provided at the bases of the walls. The footing drains should consist of a minimum 4-inch diameter rigid PVC perforated pipe, sloped to drain, with perforations placed near the bottom. The drainpipe should be enveloped by 6 inches of washed gravel in all directions wrapped in filter fabric to prevent the migration of silt and clay into the drain. The wall fill material adjacent to and extending a lateral distance of at least 2 feet behind the walls should consist of free -draining granular material. All free -draining backfill should contain less than 3 percent fines (passing the U.S. Standard No. 200 Sieve) based upon the fraction passing the U.S. Standard No. 4 Sieve with at least 30 percent of the material being retained on the U.S. Standard No. 4 Sieve. Alternatively, a drainage composite may be used. It should be realized that the primary purpose of the free -draining material is the reduction of hydrostatic pressure. Some potential for the moisture to contact the back face of the wall may exist, even with treatment, which may require that more extensive waterproofing be specified for walls, which require interior moisture sensitive finishes. We recommend that the wall fill be compacted to at least 95 percent of the maximum dry density based on ASTM D1557 Test Method. In -place density tests should be performed to verify adequate compaction. Soil compactors place transient surcharges on the backfill. Consequently, only light hand operated equipment is recommended for fill compaction within 3 feet of walls so that excessive stress is not imposed on the walls. Stormwater Management This investigation included an evaluation of the feasibility of stormwater infiltration for this project. The dense to very dense glacial till soil (hardpan) encountered in the test pits at this site are not considered suitable for the use of infiltration techniques for stormwater management. As requested by Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 15 the project civil engineer, three small-scale Pilot Infiltration Tests (PITS) were conducted at the site. The PIT results indicted some potential for slight amounts infiltration may be feasible for use in conjunction with the design of other stormwater management systems. Stormwater Infiltration Rate — Small Scale "PIT" Method: A bio-retention swale was being considered as a part of the stormwater management system for this project. Drainage plans were not available at the time this letter was prepared. The design infiltration rate has been developed based on procedures outlined in the EMC Chapter 18.30 and the Edmonds Stormwater Addendum, as well as Volume III of the Washington State Department of Ecology's "Stormwater Management Manual for Western Washington," (SMMWW, 2014 & updated 2019). Three small-scale stormwater Pilot Infiltration Tests (PIT) were performed at the property to evaluate the stormwater infiltration rate. The PIT method for evaluating the stormwater infiltration rate of the site soils generally includes an excavation, with an area of at least 12 square feet, in the area of the proposed infiltration system. The PITs were performed between depths of 2.0 and 9.0 feet below the current grade in the areas shown on the site plan in Figure 2. The bottom of the excavations for the small-scale PITs exposed test areas of approximately 15, 20 and 24 square feet. Data analysis included correction factors to determine the long-term or corrected infiltration rate. The applied correction factors were as follows: • Site Variability, CFv = 0.33 • Test Method, CFt = 0.5 • Degree of Influent, CFm = 0.9 In our opinion, a design infiltration rate of 0.2-inch per hour should be appropriate provided that pretreatment measures for control of total suspended solids are adequately maintained. The native sand and gravel materials were exposed between depths of 0.5 and 2.0 feet in the test pits. Changes in soil conditions and the corresponding infiltration rate are possible at different locations and depths. Accordingly, we recommend that the subsurface soils be evaluated during construction by a representative of the geotechnical engineer. Construction equipment should not be allowed on the soils at the base of the infiltration areas, as compaction of the soils may reduce their permeability. Bioretention Swale: We understand that a bioretention Swale is being considered for stormwater management for this project. The Swale would be located in an area between the east wall of the planned buildings and the east property line. The City of Edmonds Stormwater Addendum Checklist 10, item 23, indicates that, "If the contributing area is less than 5,000 square feet, the bioretention area Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 16 should be at least 5 feet from a structure without a basement and 10 feet from a structure with a basement." We understand that the proposed buildings will not have basements, and in our opinion, the separation between the high-water elevation of the proposed bioretention swale and the building may be reduced to 3 feet, provided the high-water elevation in the bioretention Swale is at least one -foot below the building's bottom of footing elevation. Organic Content Our laboratory in Lynnwood performed the organic content testing on selected soil samples based on ASTM D-2974. Organic content is one factor used to determine if the soil type has the potential to filter stormwater runoff. According to the SMMWW, the minimum useful organic content for filtrations is 1.0 percent. The test results for the soil samples are presented in Table 1. Table 1: Organic Content Test Pit Number Sample Depth (feet) Soil Classification Organic Content (percent) INF-2 9.0 Gray Silty Sand with Gravel 0.6 INF-3 2.0 Brown Silty Sand with Gravel and Trace Organics 2.4 Cation Exchange Capacity Cation Exchange Capacity (CEC) refers to the ability of soil to hold cation nutrients. Different soil types have different CEC values. In general, clay, silt and organic matter tend to have higher CEC values than sand and gravel. CEC is typically measured in millequivalents (meq). Stormwater system designers often use the CEC information to determine if the on -site soils have the potential to filter or clean stormwater runoff. According to the SMMWW, the minimum useful CEC is 5.0 meq/100g dry soil. Soil samples from Infiltration Test Pits INF-2 and INF-3 were processed by KTL (KUO Testing Labs) in Othello, WA for Cation Exchange Capacity determination. The CEC test results are presented below in Table 2. Detailed test results information from KUO Testing Labs is attached to this report. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 17 Table 2: Cation Exchange Capacity Test Pit Number Sample Depth Soil Classification Cation Exchange (feet) Capacity (meq) INF-2 9.0 Gray Silty Sand with 2.2 Gravel INF-3 2.0 Brown Silty Sand with 5.5 Gravel and Trace Organics Erosion and Sediment Control Erosion and sediment control (ESC) is used to minimize the transportation of sediment to wetlands, streams, lakes, drainage systems, and adjacent properties. Erosion and sediment control measures should be taken and these measures should be in general accordance with local regulations. As a minimum, the following basic recommendations should be incorporated into the design of the erosion and sediment control features of the site: 1) Phase the soil, foundation, utility and other work, requiring excavation or the disturbance of the site soils, to take place during the dry season (generally May through September). However, provided precautions are taken using Best Management Practices (BMP's), grading activities can be undertaken during the wet season (generally October through April), but it should also be known that this may increase the overall cost of the project. 2) All site work should be completed and stabilized as quickly as possible. 3) Additional perimeter erosion and sediment control features may be required to reduce the possibility of sediment entering the surface water. This may include additional silt fences, silt fences with a higher Apparent Opening Size (AOS), construction of a berm, or other filtration systems. 4) Any runoff generated by dewatering discharge should be treated through construction of a sediment trap if there is sufficient space. If space is limited, other filtration methods will need to be incorporated. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. Groundwater Influence on Structures and Earthwork Construction KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 18 Groundwater seepage was not encountered in the test pits extending to 11.0 feet below the surface during our exploration of this site. However, it is our opinion that perched groundwater could occur on this property, especially during and after prolonged periods of wet weather. It should be recognized that groundwater elevations may fluctuate with time. If groundwater is encountered during construction, we should observe the conditions to determine if dewatering will be needed. Design of temporary dewatering systems to remove groundwater should be the responsibility of the contractor. Care should be taken to protect foundation subgrades from disturbance when groundwater or wet soils are encountered. If earthwork is performed during or soon after periods of precipitation, the subgrade soils may become saturated. These soils may "pump," and the materials may not respond to densification techniques. Typical remedial measures include: disking and aerating the soil during dry weather; mixing the soil with drier materials; removing and replacing the soil with an approved fill material. A qualified geotechnical engineering firm should be consulted prior to implementing remedial measures to observe the unstable subgrade conditions and provide appropriate recommendations. Drainage and Landscaping The ground surface should slope away from building pads and pavement areas, toward appropriate drop inlets or other surface drainage devices. It is recommended that adjacent exterior grades be sloped a minimum of 2 percent for a minimum distance of 5 feet away from structures. We recommend the installation of foundation drains with cleanouts for this project. The foundation drains should consist of a minimum 4-inch diameter perforated pipe, sloped to drain, with perforations placed down and enveloped by 6 inches of washed gravel in all directions and filter fabric to limit the migration of silt and clay into the drains. Roof drains should be tightlined away from the foundations. Roof drains should not be connected to the foundation drains. Subgrade soils in pavement areas should be inclined at a minimum of 1 percent and drainage gradients should be maintained to carry all surface water to collection facilities, and suitable outlets. These grades should be maintained for the life of the development. Specific recommendations for and design of storm water disposal systems are beyond the scope of our services and should be prepared by other consultants that are familiar with design and discharge requirements. Utility Trench Backfill Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 19 Utility trenches should be excavated according to accepted engineering practices following OSHA (Occupational Safety and Health Administration) standards, by a contractor experienced in such work. The responsibility for the safety of open trenches should be borne by the contractor. Traffic and vibration adjacent to trench walls should be minimized; cyclic wetting and drying of excavation side slopes should be avoided. Depending upon the location and depth of some utility trenches, groundwater flow into open excavations could be experienced, especially during or shortly following periods of precipitation. All utility trench backfill should consist of structural fill. Utility trench backfill placed in or adjacent to buildings and exterior slabs should be compacted to at least 95 percent of the maximum dry density based on ASTM Test Method D1557. The upper 5 feet of utility trench backfill placed in pavement areas should be compacted to at least 95 percent of the maximum dry density based on ASTM Test Method D1557. Below 5 feet, utility trench backfill in pavement areas should be compacted to at least 90 percent of the maximum dry density based on ASTM Test Method D1557. Pipe bedding should be in accordance with the pipe manufacturer's recommendations. The contractor is responsible for removing all water -sensitive soils from the trenches regardless of the backfill location and compaction requirements. The contractor should use appropriate equipment and methods to avoid damage to the utilities and/or structures during fill placement and compaction. Testing and Inspection A representative of Krazan & Associates, Inc. should be present at the site during the earthwork activities to confirm that actual subsurface conditions are consistent with the exploratory fieldwork. This activity is an integral part of our services as acceptance of earthwork construction is dependent upon compaction testing and stability of the material. This representative can also verify that the intent of these recommendations is incorporated into the project design and construction. Krazan & Associates, Inc. will not be responsible for grades or staking, since this is the responsibility of the Prime Contractor. Furthermore, Krazan & Associates is not responsible for the contractor's procedures, methods, scheduling or management of the work site. Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. LIMITATIONS KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 20 Geotechnical engineering is one of the newest divisions of Civil Engineering. This branch of Civil Engineering is constantly improving as new technologies and understanding of earth sciences improves. Although your site was analyzed using the most appropriate current techniques and methods, undoubtedly there will be substantial future improvements in this branch of engineering. In addition to improvements in the field of geotechnical engineering, physical changes in the site either due to excavation or fill placement, new agency regulations or possible changes in the proposed structure after the time of completion of the soils report may require the soils report to be professionally reviewed. In light of this, the owner should be aware that there is a practical limit to the usefulness of this report without critical review. Although the time limit for this review is strictly arbitrary, it is suggested that two years be considered a reasonable time for the usefulness of this report. Foundation and earthwork construction are characterized by the presence of a calculated risk that soil and groundwater conditions have been fully revealed by the original foundation investigation. This risk is derived from the practical necessity of basing interpretations and design conclusions on limited sampling of the earth. Our report, design conclusions and interpretations should not be construed as a warranty of the subsurface conditions. Actual subsurface conditions may differ, sometimes significantly, from those indicated in this report. The recommendations made in this report are based on the assumption that soil conditions do not vary significantly from those disclosed during our field investigation. The findings and conclusions of this report can be affected by the passage of time, such as seasonal weather conditions, manmade influences, such as construction on or adjacent to the site, natural events such as earthquakes, slope instability, flooding, or groundwater fluctuations. If any variations or undesirable conditions are encountered during construction, the geotechnical engineer should be notified so that supplemental recommendations can be made. The conclusions of this report are based on the information provided regarding the proposed construction. If the proposed construction is relocated or redesigned, the conclusions in this report may not be valid. The geotechnical engineer should be notified of any changes so that the recommendations can be reviewed and reevaluated. Misinterpretations of this report by other design team members can result in project delays and cost overruns. These risks can be reduced by having Krazan & Associates, Inc. involved with the design teams' meetings and discussions after submitting the report. Krazan & Associates, Inc. should also be retained for reviewing pertinent elements of the design team's plans and specifications. Contractors can also misinterpret this report. To reduce this, risk Krazan & Associates. Inc. should participate in pre -bid and preconstruction meetings, and provide construction observations during the site work. This report is a geotechnical engineering investigation. The scope of our services did not include any environmental site assessment for the presence or absence of hazardous and/or toxic materials in the soil, Krazan & Associates, Inc. Offices Serving The Western United States Krazan & Associates, Inc. KA No. 092-22001 Glacier Offices and Warehouse 7509 21211' Street SW Edmonds, WA February 04, 2022 Page No. 21 groundwater or atmosphere, or the presence of wetlands. Any statements or absence of statements, in this report or on any soils log regarding odors, unusual or suspicious items, or conditions observed are strictly for descriptive purposes and are not intended to convey engineering judgment regarding potential hazardous and/or toxic assessments. The geotechnical information presented herein is based upon professional interpretation utilizing standard engineering practices and a degree of conservatism deemed proper for this project. It is not warranted that such information and interpretation cannot be superseded by future geotechnical developments. We emphasize that this report is valid for this project as outlined above, and should not be used for any other site. Our report is prepared for the exclusive use of our client. No other party may rely on the product of our services unless we agree in advance to such reliance in writing. CLOSURE If you have any questions, or if we may be of further assistance, please do not hesitate to contact our office at (425) 485-5519. Respectfully submitted, KRAZAN & ASSOCIATES, INC. Michael D Rundquist, PE Senior Project Manager MDR 02/04/2022 Krazan & Associates, Inc. Offices Serving The Western United States Vicinity Map N (Not to Scale) 196TH ST SW t Z 524� I j 524 �'rrll�i r Edmonds 200TH ST SW Community Coll -Central 200TH ST SW Al, +Nasl ingto A Univ 202NO ST SW 10ITH ST SW Cedar 3 Approximate t Valley W z II Site Area Seattle m Q 1� 2oarH sr sw � 21orH sr sw ri,+rr 3 L+ki w 12TH ST SW - t 3 Z � I W Q 3 Z e i n j I © 216TH ST SW 2: N 218TH ST SW north ST SW 3FT —C'husc Z 3 —Luke = a t 224TH ST SW — SW 3 0 sper , e 226TH PL SW Q 3 3 —w w ik 228TH'ST•SW $ o j i 230TH ST,sW Y W A 3 7509 212th St SW, Edmonds, WA Reference: The Vicinity Map is based on the USGS topographic map titled, i"Edmonds East Quadrangle - Washington - 7.5-min Series", dated 2017. �I�alZ & ASSOCIATES,INC. Glacier Offices and Warehouse - 7509 212th St SW, Edmonds, WA Date: January 2022 Project Number: 092-22001 Drawn By: NG Figure 1 Not to scale Site Plan N (Not to Scale) ---------------- -------------------------- I TP-2 I I _____ Gra_1[Ql---------- I Asphalt f Jy TP-1 Trash Area I Proposed Outdoor I Storage I (Future Addition) I INF-2 I I Proposed 1-Story Warehouse I Building I I TP_3 00 I a, C I I m D L7 I INF-1 I I Proposed I 2-Story I I Office , Building I ; ; TP-4 I I ; 212th St SW Reference: The site plan is based on the preliminary site plan titled, LEGEND"Glacier Environmental Services New Construction" by TG Architect dated 12/30/21. TP-1 1<1:-az;arl& s S C 1 T E s, 1 N C. Number and Approximate L� L� Location of Test Pit INF-1 Glacier Offices and Warehouse - 7509 212th St SW, Edmonds, WA Number and Approximate "PIT' Locations of Small Scale Date: January 2022 Project Number: 092-22001 -------- Approximate Property Line Drawn By: NG Figure 2 Not to scale APPENDIX A FIELD INVESTIGATION AND LABORATORY TESTING Field Investigation The field investigation consisted of a surface reconnaissance and a subsurface exploration program. Four (4) test pits and three (3) infiltration test pits were excavated, performed and sampled at the property for the subsurface exploration at this site. The test pits explorations were excavated to depths ranging from approximately 4.0 feet to 11.0 feet below the existing ground surface using a trackhoe excavator provided by the client. Locations of the soil explorations are shown on the Site Plan in Figure 2. The depths shown on the attached soil logs are from the existing ground surface at the time of the explorations. The soils encountered were logged in the field during the subsurface exploration and, with supplementary laboratory test data, are described in accordance with the Unified Soil Classification System (USCS). All samples from the explorations were returned to our laboratory for evaluation. The logs of the soil explorations along with the laboratory test results are presented in this appendix. Laboratory Testing The laboratory testing program was developed primarily to determine the physical characteristics of the soils. Test results were used for soil classification and as criteria for determining the engineering suitability of the subsurface materials encountered. Krazan and Associates, Inc. Offices Serving The Western United States Soil Classification USCS Soil Classification Major Division Group Description Coarse- Grained Soils Gravel and Gravelly Soils < 50% coarse fraction passes #4 sieve Gravel (with little or no fines) GW Well -Graded Gravel GP Poorly Graded Gravel Gravel (with > 12% fines) GM Silty Gravel GC Clayey Gravel < 50% passes #200 sieve Sand and Sandy Soils > 50% coarse fraction passes #4 sieve Sand (with little or no fines) SW Well -Graded Sand SP Poorly Graded Sand Silty Sand Sand (with > 12% fines) SM SC Clayey Sand Fine- Grained Soils Silt and Clay Liquid Limit < 50 ML Silt CL Lean Clay OL Organic Silt and Clay (Low Plasticity) > 50% passes #200 sieve Silt and Clay Liquid Limit > 50 MH Inorganic Silt CH Inorganic Clay OH Organic Clay and Silt (Med. to High Plasticity) Highly Organic Soils PT Peat Relative Density with Respect to SPT N-Value Coarse -Grained Soils Fine -Grained Soils Density N-Value (Blows/Ft) Density N-Value (Blows/Ft) Very Loose 0-4 Very Soft 0-1 Loose 5 -10 Soft 2-4 Medium Dense 11 - 30 Medium Stiff 5-8 Dense 31 -50 Stiff 9 - 15 Very Dense > 50 Very Stiff 16 - 30 Hard > 30 LOG OF EXPLORATORY TEST PIT INF-1 KRAZAN AND ASSOCIATES, INC. PROJECT: Glacier Offices&Warehouse DATE: 01/24/22 PROJECT NO.: 092-22001 PAGE: 1 of 1 CONTRACTOR: Glacier Environmental SURFACE ELEV.: --390' SAMPLE METHOD: Grab LOCATION: Edmonds, WA Natural Moisture Content and Atterberg Limits J m J W J MATERIAL DESCRIPTION Z W n, Plastic Moisture Liquid _ > Lu -j -j Limit Content Limit w W a a o? N N 10 30 50 70 t-- -t Topsoil P - - - -------------------------------------------------------------------------------------------------------------------------- Gray Silty Sand with Gravel 1 (Moist, Loose)(Undocumented Fill) 2 Brown Silty Sand with Gravel and Trace Organics (SM) (Moist, Loose to Medium Dense)(Native Weathered Soils) 1 G 3 ' Gray Silty Sand with Gravel (SM) (Moist, Dense)(Native Glacial Soils) is 2 G 6 is 3 G 8 is - Small Scale "PIT" Depth - 4 G 10 End of Exploratory Test Pit 12 13 Water Level Initial: 0 Final: V Water Observations: Groundwater seepage was not observed. Notes: -- LOG OF EXPLORATORY TEST PIT INF- KR z N AND ASSOCIATES, INC. PROJECT: Glr ofies&Aareh_se DATE: e/42/22 PROJECT NO:m2- 001PAGE: 1g1 CONTRACTOR: Glacier Environmental SURFaE ELEV.: -3K' SAMPLE METHomo Grab LOCATION: Edmonds, AA Natural Moisture Content and a!lerberg Limb ¢ MATERIAL DESCRIPTION ) CL mea Moisture bps, F > w ) o m. Content Limit IL a Lu § k k k q m y 3 #k Topsoil �ma ------ — — — — — — — — — — — — — — — — — — — — — —-----c- ---- • Brown &lylSand with Gravel and Trace Organics (S9) G I. (9dkLoose to Medium Dns)(NkvWeathered Soils) 2 ... ... ... ------------------------------------------------------------------------------------------------------------------------------------------- Olive-Brown Sly! Sand with Gravel and Trace Omani (S9) as a\ (9dkDmm)(N+m Glacial Soils) 2 � 4 \\} 5 \\\ 8 \\\ 7 \\/ a \ /\\ Soil becomes gray. \\ is g ITG _Small Scale ?I2 Depth - 3 1O \\\ En ¥ Exploratory Test m! 12 1a Aa ray. ¥m» 2 Fier! Water Observaea:Groundwater seepage was not observed. Notes: -- LOG OF EXPLORATORY TEST PIT INF-3 KRAZAN AND ASSOCIATES, INC. PROJECT: Glacier Offices&Warehouse DATE: 01/24/22 PROJECT NO.: 092-22001 PAGE: 1 of 1 CONTRACTOR: Glacier Environmental SURFACE ELEV.: --390' SAMPLE METHOD: Grab LOCATION: Edmonds, WA Natural Moisture Content and Atterberg Limits J m J W J MATERIAL DESCRIPTION Z W n, Plastic Moisture Liquid _ > Lu _j _j Limit Content Limit w W a a o? N N 10 30 50 70 t-- -t Topsoil To p a - - - -- -- - -- - - - - -- -- -- -- -- - - -------------------------------------------------------------------------------- Dark Yellowish -Brown Sand with Silt, Gravel and Trace Organics I. (SP SM) (Moist, Loose to Medium Dense)(Native Weathered Soils) . 9.1 2 Small Scale "PIT" Depth - 1 G 2G Gray Silty � Sand with Gravel SM) (Moist, Dense)(Native Glacial Soils) 4 6 End of Exploratory Test Pit 7 8 9 10 11 12 13 Water Level Initial: 0 Final: V Water Observations: Groundwater seepage was not observed. Notes: -- LOG OF EXPLORATORY TEST PIT TP-1 KRAZAN AND ASSOCIATES, INC. PROJECT: Glacier Offices&Warehouse DATE: 01/24/22 PROJECT NO.: 092-22001 PAGE: 1 of 1 CONTRACTOR: Glacier Environmental SURFACE ELEV.: --390' SAMPLE METHOD: Grab LOCATION: Edmonds, WA Natural Moisture Content and Atterberg Limits J m J W J MATERIAL DESCRIPTION Z W n, Plastic Moisture Liquid _ > Lu -j -j Limit Content Limit w W a a o? N N 10 30 50 70 Topsoil a -- -- -- -- - - -- -- - - ---------------------------------------------------------------------------------------------------- ` Brown Silty Sand with Gravel and Trace Organics (SM) 1 I. (Moist, Loose to Medium Dense)(Native Weathered Soils) ------------------------------------------------------------------------------------------------------------------------------------------ Gray Silty Sand with Gravel (SM) 2 G (Moist, Dense)(Native Glacial Soils) End of Exploratory Test Pit 5 6 7 8 9 10 11 12 13 Water Level Initial: 0 Final: V Water Observations: Groundwater seepage was not observed. Notes: -- LOG OF EXPLORATORY TEST PIT TP-2 KRAZAN AND ASSOCIATES, INC. PROJECT: Glacier Offices&Warehouse DATE: 01/24/22 PROJECT NO.: 092-22001 PAGE: 1 of 1 CONTRACTOR: Glacier Environmental SURFACE ELEV.: --390' SAMPLE METHOD: Grab LOCATION: Edmonds, WA Natural Moisture Content and Atterberg Limits J J W W n, m W MATERIAL DESCRIPTION Z Plastic Moisture Liquid _ > -j -j Limit Content Limit w W a a o? N N 10 30 50 70 Topsoil and Forest Duff --------------------------------------------------------------------------------------------------------------------------------------- Brown Silty Sand with Gravel and Trace Organics (SM) 1 G (Moist, Loose to Medium Dense)(Native Weathered Soils) 3 ' Gray Silty Sand with Gravel (SM) 2 G (Moist, Dense)(Native Glacial Soils) End of Exploratory Test Pit 5 6 7 8 9 10 11 12 13 Water Level Initial: 0 Final: V Water Observations: Groundwater seepage was not observed. Notes: -- LOG OF EXPLORATORY TEST PIT TP-3 KRAZAN AND ASSOCIATES, INC. PROJECT: Glacier Offices&Warehouse DATE: 01/24/22 PROJECT NO.: 092-22001 PAGE: 1 of 1 CONTRACTOR: Glacier Environmental SURFACE ELEV.: --390' SAMPLE METHOD: Grab LOCATION: Edmonds, WA Natural Moisture Content and Atterberg Limits J m J W J MATERIAL DESCRIPTION Z W n, Plastic Moisture Liquid _ > Lu -j -j Limit Content Limit w W a a o? N N 10 30 50 70 Topsoil a -- -- -- -- - - -- -- - - ---------------------------------------------------------------------------------------------------- ` Brown Silty Sand with Gravel and Trace Organics (SM) 1 I. (Moist, Loose to Medium Dense)(Native Weathered Soils) 1 G Gray Silty Sand with Gravel (SM) 2 G (Moist, Dense)(Native Glacial Soils) End of Exploratory Test Pit 5 6 7 8 9 10 11 12 13 Water Level Initial: 0 Final: V Water Observations: Groundwater seepage was not observed. Notes: -- LOG OF EXPLORATORY TEST PIT TP-4 KRAZAN AND ASSOCIATES, INC. PROJECT: Glacier Offices&Warehouse DATE: 01/24/22 PROJECT NO.: 092-22001 PAGE: 1 of 1 CONTRACTOR: Glacier Environmental SURFACE ELEV.: --390' SAMPLE METHOD: Grab LOCATION: Edmonds, WA Natural Moisture Content and Atterberg Limits J m J W J MATERIAL DESCRIPTION Z W n, Plastic Moisture Liquid _ > Lu -j -j Limit Content Limit w W a a o? N N 10 30 50 70 Topsoil a -- -- -- -- - - -- -- - - ---------------------------------------------------------------------------------------------------- ` Brown Silty Sand with Gravel and Trace Organics (SM) 1 I. (Moist, Loose to Medium Dense)(Native Weathered Soils) ------------------------------------------------------------------------------------------------------------------------------------------ Gray Silty Sand with Gravel (SM) 2 G (Moist, Dense)(Native Glacial Soils) End of Exploratory Test Pit 5 6 7 8 9 10 11 12 13 Water Level Initial: 0 Final: V Water Observations: Groundwater seepage was not observed. Notes: -- KRAZAN & ASSOCIATES, INC. TEST REPORT (Page 1 of 1) Job Name: Glacier Office & Warehouse Job # : 092-22001 Glacier Enviromental Services, Inc. 1 /25/2022 Laboratory Determination of Water (Moisture) Content of Soils by Mass (ASTM D-2216) Sample ID Sample Description Boring / Test Pit Depth Wet & Tare Dry &Tare Tare Results 77382-A Brown silty sand with gravel and trace of organics INF-2 0.5' 1148.0 1059.4 202.9 10.3% 77382-B Olive -brown silty sand with gravel and trace of organics INF-2 3.0' 1265.3 1178.2 174.7 8.7% 77382-C Gray silty sand with gravel INF-2 9.0' 1089.7 1012.1 173.3 9.3% 77382-D Dark yellowish -brown poorly graded sand with silt, gravel and trace of organics INF-3 2.0' 1009.4 942.6 206.3 9.1% Tested By: Cole Demas Checked By: Corbett Mercer (Lab Manager) Revision 3 1 /21 /09 X W Z Z W U Of W 0- 100 90 80 70 60 50 40 30 20 10 0 Krazan & Associates Sieve Analysis _ o00 f0V M f0 M N n \ M 7k ik ik ik ik ik ik 7k ik T- --F-- T--7-M I i 100 10 1 0.1 0.01 0.001 GRAIN SIZE - mm. % +3" % Gravel % Sand % Fines Coarse Fine Coarse Medium Fine Silt Clay 0.0 6.5 17.1 10.2 17.7 27.8 20.7 Test Results (ASTM C-136 & ASTM C-117) Opening Percent Spec." Pass? Size Finer (Percent) (X=Fail) 1.5 100.0 1 95.2 .75 93.5 .5 83.9 .375 79.9 #4 76.4 #10 66.2 #20 57.6 #40 48.5 #60 37.4 #100 28.7 #200 20.7 Material Description Brown silty sand with gravel and trace of organics. Atterberg Limits (ASTM D 4318) PL= NP LL= NV Pl= NP Classification USCS (D 2487)= SM AASHTO (M 145)= A-1-b Coefficients D90= 16.0947 D85= 13.2939 D60= 1.0906 D50= 0.4629 D80= 0.1645 D15= D10= Cu= Cc= Remarks Natural Moisture Content (ASTM D-2216): 10.3% Date Received: 1/25/2022 Date Tested: 1/27/2022 Tested By: Cole Demas Checked By: Corbett Mercer Title: Lab Manager (no specification provided) Location: INF-2 Date Sampled: 1/25/2022 Sample Number: 77382-A Depth: 0.5' Client: Glacier Environmental Services, Inc. J<X Project: Glacier Office & Warehouse .�� !Y W Z Z W U IY W d 100 90 80 70 60 50 40 30 20 10 0 Krazan & Associates Sieve Analysis _ o00 f0V M f0 M N n \ M 7k ik ik ik ik ik ik 7k ik vi� i i i i i 100 10 1 0.1 0.01 0.001 GRAIN SIZE - mm. % +3" % Gravel % Sand % Fines Coarse Fine Coarse Medium Fine Silt Clay 0.0 10.4 20.3 12.4 17.0 25.7 14.2 Test Results (ASTM C-136 & ASTM C-117) Opening Percent Spec." Pass? Size Finer (Percent) (X=Fail) 1.5 100.0 1.25 92.6 1 89.6 .75 89.6 .5 81.8 .375 79.0 .25 73.9 #4 69.3 #10 56.9 #20 48.8 #40 39.9 #60 29.0 #100 20.9 #200 14.2 Material Description Olive -brown silty sand with gravel and trace of organics. Atterberg Limits (ASTM D 4318) PL= NP LL= NV PI= NP Classification USCS (D 2487)= SM AASHTO (M 145)= A-1-b Coefficients D90= 27.5511 D85= 14.8273 D60= 2.5632 D50= 0.9679 D80= 0.2629 D15= 0.0822 D10= Cu= Cc= Remarks Natural Moisture Content (ASTM D-2216): 8.7% Date Received: 1/25/2022 Date Tested: 1/27/2022 Tested By: Cole Demas Checked By: Corbett Mercer Title: Lab Manager (no specification provided) Location: INF-2 Date Sampled: 1/25/2022 Sample Number: 77382-B Depth: 3.0' Client: Glacier Environmental Services, Inc. Project: Glacier Office &Warehouse J<X . X W Z Z W U IY W d 100 90 80 70 60 50 40 30 20 10 0 Krazan & Associates Sieve Analysis _ ... f0V M V (D � � N f0 M N n \ M 7k ik ik ik ik ik ik 7k ik i i i 100 10 1 0.1 0.01 0.001 GRAIN SIZE - mm. % +3" % Gravel % Sand % Fines Coarse Fine Coarse Medium Fine Silt Clay 0.0 1.5 16.9 6.7 19.3 37.5 18.1 Test Results (ASTM C-136 & ASTM C-117) Opening Percent Spec." Pass? Size Finer (Percent) (X=Fail) 1 100.0 .75 98.5 .5 91.3 .375 88.8 .25 84.1 #4 81.6 #10 74.9 #20 67.1 #40 55.6 #60 40.0 #100 27.7 #200 18.1 Material Description Gray silty sand with gravel Atterbera Limits (ASTM D 4318 PL= NP LL= NV PI= NP Classification USCS (D 2487)= SM AASHTO (M 145)= A-2-4(0) Coefficients D90= 11.1440 D85= 6.8454 D60= 0.5200 D50= 0.3478 D30= 0.1684 D15= D10= Cu= Cc= Remarks Natural Moisture Content (ASTM D-2216): 9.3% Organic Content of Soils (ASTM D-2974): 0.6% Date Received: 1/25/2022 Date Tested: 1/28/2022 Tested By: Cole Demas Checked By: Corbett Mercer Title: Lab Manager (no specification provided) Location: INF-2 Date Sampled: 1/25/2022 Sample Number: 77382-C Depth: 9.0' Client: Glacier Environmental Services, Inc. Project: Glacier Office &Warehouse J<X . !Y W Z Z W U Of W 0- 100 90 80 70 60 50 40 30 20 10 0 Krazan & Associates Sieve Analysis _ o00 f0V M f0 M N n \ M 7k ik ik ik ik ik ik 7k ik 100 10 1 0.1 0.01 0.001 GRAIN SIZE - mm. % +3" % Gravel % Sand % Fines Coarse Fine Coarse Medium Fine Silt Clay 0.0 14.8 19.6 7.4 16.1 30.1 12.0 Test Results (ASTM C-136 & ASTM C-117) Opening Percent Spec." Pass? Size Finer (Percent) (X=Fail) 1.5 100.0 1 94.6 .75 85.2 .5 77.2 .375 73.5 .25 69.1 #4 65.6 #10 58.2 #20 51.3 #40 42.1 #60 29.0 #100 19.1 #200 12.0 Material Description Dark yellowish -brown poorly graded sand with silt, gravel and trace of organics Atterberg Limits (ASTM D 4318) PL= NP LL= NV Pl= NP Classification USCS (D 2487)= SP-SM AASHTO (M 145)= A-1-b Coefficients D90= 21.9789 D85= 18.9524 D60= 2.5675 D50= 0.7415 D80= 0.2603 D15= 0.1061 D10= Cu= Cc= Remarks Natural Moisture Content (ASTM D-2216): 9.1% Organic Content of Soils (ASTM D-2974): 2.4% Date Received: 1/25/2022 Date Tested: 1/28/2022 Tested By: Cole Demas Checked By: Corbett Mercer Title: Lab Manager (no specification provided) Location: INF-3 Date Sampled: 1/25/2022 Sample Number: 77382-D Depth: 2.0' Client: Glacier Environmental Services, Inc. J<X Project: Glacier Office & Warehouse .�� Report Date: February 3, 2022 Report No: 84664 Client: Krazan & Associates, Inc. Sampler: Corbett Mercer Project: Glacier Office Field: P.N.: 092-22001 - 2022 Control Samples Sampled: 1 /25/2022 k1rfrL KIJOTESTI NG LABS A Matrix Sciences Company SOIL ANALYSIS REPORT Lab # Depth Field Sample CEC Inches ID ID Meq/ Start End 1000 9451 9452 77382-C (INF-2 @ 9') 77382-D (INF-3 @ 2') Main Office: 119 E Main St., Othello, WA 99344 Oregon Office: 1300 Sixth St., Suite J, Umatilla, OR 97882 Pasco Office: 1320 E Spokane St., Pasco, WA 99301 to (509) 488-0112 ® info@kuotestinglabs.com 2.2 5.5 APPENDIX B EARTHWORK SPECIFICATIONS GENERAL When the text of the report conflicts with the general specifications in this appendix, the recommendations in the report have precedence. SCOPE OF WORK: These specifications and applicable plans pertain to and include all earthwork associated with the site rough grading, including but not limited to the furnishing of all labor, tools, and equipment necessary for site clearing and grubbing, stripping, preparation of foundation materials for receiving fill, excavation, processing, placement and compaction of fill and backfill materials to the lines and grades shown on the project grading plans, and disposal of excess materials. PERFORMANCE: The Contractor shall be responsible for the satisfactory completion of all earthwork in accordance with the project plans and specifications. This work shall be inspected and tested by a representative of Krazan and Associates, Inc., hereinafter known as the Geotechnical Engineer and/or Testing Agency. Attainment of design grades when achieved shall be certified to by the project Civil Engineer. Both the Geotechnical Engineer and Civil Engineer are the Owner's representatives. If the contractor should fail to meet the technical or design requirements embodied in this document and on the applicable plans, he shall make the necessary readjustments until all work is deemed satisfactory as determined by both the Geotechnical Engineer and Civil Engineer. No deviation from these specifications shall be made except upon written approval of the Geotechnical Engineer, Civil Engineer or project Architect. No earthwork shall be performed without the physical presence or approval of the Geotechnical Engineer. The Contractor shall notify the Geotechnical Engineer at least 2 working days prior to the commencement of any aspect of the site earthwork. The Contractor agrees that he shall assume sole and complete responsibility for job site conditions during the course of construction of this project, including safety of all persons and property; that this requirement shall apply continuously and not be limited to normal working hours; and that the Contractor shall defend, indemnify and hold the Owner and the Engineers harmless from any and all liability, real or alleged, in connection with the performance of work on this project, except for liability arising from the sole negligence of the Owner of the Engineers. TECHNICAL REQUIREMENTS: All compacted materials shall be densified to a density not less than 95 percent of maximum dry density as determined by ASTM Test Method D1557 as specified in the technical portion of the Geotechnical Engineering Report. The results of these tests and compliance with these specifications shall be the basis upon which satisfactory completion of work will be judged by the Geotechnical Engineer. SOIL AND FOUNDATION CONDITIONS: The Contractor is presumed to have visited the site and to have familiarized himself with existing site conditions and the contents of the data presented in the soil report. The Contractor shall make his own interpretation of the data contained in said report, and the Contractor shall not be relieved of liability under the contractor for any loss sustained as a result of any variance between conditions indicated by or deduced from said report and the actual conditions encountered during the progress of the work. Krazan and Associates, Inc. Offices Serving The Western United States DUST CONTROL: The work includes dust control as required for the alleviation or prevention of any dust nuisance on or about the site or the borrow area, or off -site if caused by the Contractor's operation either during the performance of the earthwork or resulting from the conditions in which the Contractor leaves the site. The Contractor shall assume all liability, including Court costs of codefendants, for all claims related to dust or windblown materials attributable to his work. SITE PREPARATION Site preparation shall consist of site clearing and grabbing and preparations of foundation materials for receiving fill. CLEARING AND GRUBBING: The Contractor shall accept the site in this present condition and shall demolish and/or remove from the area of designated project earthwork all structures, both surface and subsurface, trees, brush, roots, debris, organic matter, and all other matter determined by the Geotechnical Engineer to be deleterious. Such materials shall become the property of the Contractor and shall be removed from the site. Tree root systems in proposed building areas should be removed to a minimum depth of 3 feet and to such an extent which would permit removal of all roots larger than 1 inch. Tree root removed in parking areas may be limited to the upper P/2 feet of the ground surface. Backfill or tree root excavation should not be permitted until all exposed surfaces have been inspected and the Geotechnical Engineer is present for the proper control of backfill placement and compaction. Burning in areas, which are to receive fill materials, shall not be permitted. SUBGRADE PREPARATION: Surfaces to receive Structural fill shall be prepared as outlined above, excavated/scarified to a depth of 12 inches, moisture -conditioned as necessary, and compacted to 95 percent compaction. Loose and/or areas of disturbed soils shall be moisture conditioned and compacted to 95 percent compaction. All ruts, hummocks, or other uneven surface features shall be removed by surface grading prior to placement of any fill material. All areas which are to receive fill materials shall be approved by the Geotechnical Engineer prior to the placement of any of the fill material. EXCAVATION: All excavation shall be accomplished to the tolerance normally defined by the Civil Engineer as shown on the project grading plans. All over excavation below the grades specified shall be backfilled at the Contractor's expense and shall be compacted in accordance with the applicable technical requirements. FILL AND BACKFILL MATERIAL: No material shall be moved or compacted without the presence of the Geotechnical Engineer. Material from the required site excavation may be utilized for construction site fills provided prior approval is given by the Geotechnical Engineer. All materials utilized for constructing site fills shall be free from vegetable or other deleterious matter as determined by the Geotechnical Engineer. PLACEMENT, SPREADING AND COMPACTION: The placement and spreading of approved fill materials and the processing and compaction of approved fill and native materials shall be the responsibility of the Contractor. However, compaction of fill materials by flooding, ponding, or jetting shall not be permitted unless specifically approved by local code, as well as the Geotechnical Engineer. Both cut and fill shall be surface compacted to the satisfaction of the Geotechnical Engineer prior to final acceptance. Krazan and Associates, Inc. Offices Serving The Western United States SEASONAL LIMITS: No fill material shall be placed, spread, or rolled while it is frozen or thawing or during unfavorable wet weather conditions. When the work is interrupted by heavy rains, fill operations shall not be resumed until the Geotechnical Engineer indicates that the moisture content and density of previously placed fill are as specified. Krazan and Associates, Inc. Offices Serving The Western United States Appendix C Page C. APPENDIX C PAVEMENT SPECIFICATIONS 1. DEFINITIONS — The term "pavement' shall include asphalt concrete surfacing, untreated aggregate base, and aggregate subbase. The term "subgrade" is that portion of the area on which surfacing, base, or subbase is to be placed. 2. SCOPE OF WORK — This portion of the work shall include all labor, materials, tools and equipment necessary for and reasonable incidental to the completion of the pavement shown on the plans and as herein specified, except work specifically noted as "Work Not Included." 3. PREPARATION OF THE SUBGRADE — The Contractor shall prepare the surface of the various subgrades receiving subsequent pavement courses to the lines, grades, and dimensions given on the plans and as per the pavement design section of this report. The upper 12 inches of the soil subgrade beneath the pavement section shall be compacted to a minimum compaction of 95% of maximum dry density as determined by test method ASTM D1557. The finished subgrades shall be tested and approved by the Geotechnical Engineer prior to the placement of additional pavement of additional pavement courses. 4. AGGREGATE BASE — The aggregate base shall be spread and compacted on the prepared subgrade in conformity with the lines, grades, and dimensions shown on the plans. The aggregate base should conform to WSDOT Standard Specification for Crushed Surfacing Base Course or Top Course (Item 9-03.9(3)). The base material shall be compacted to a minimum compaction of 95% as determined by ASTM D1557. Each layer of subbase shall be tested and approved by the Geotechnical Engineer prior to the placement of successive layers. 5. ASPHALTIC CONCRETE SURFACING — Asphaltic concrete surfacing shall consist of a mixture of mineral aggregate and paving grade asphalt, mixed at central mixing plant and spread and compacted on a prepared base in conformity with the lines, grades, and dimensions shown on the plans. The drying, proportioning, and mixing of the materials shall conform to WSDOT Specifications. The prime coat, spreading and compacting equipment, and spreading and compacting the mixture shall conform to WSDOT Specifications, with the exception that no surface course shall be placed when the atmospheric temperature is below 50 degrees F. The surfacing shall be rolled with combination steel - wheel and pneumatic rollers, as described in WSDOT Specifications. The surface course shall be placed with an approved self-propelled mechanical spreading and finishing machine. 6. TACK COAT — The tack (mixing type asphaltic emulsion) shall conform to and be applied in accordance with the requirements of WSDOT Specifications. Krazan and Associates, Inc. Offices Serving The Western United States ccit-o APPENDIX C STORMWATER MANAGEMENT SYSTEM MODELING REPORT TECHNICAL INFORMATION REPORT 212t" Street Site Redevelopment Edmonds, Washington CEKO PN: 22017.01 CAC EKO\ProjectslActive122017.01-Glacier-Headquarters\Engineering\TIR\2024-07-Stormwater-TI R.docx 4UiU—/1CO, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com WWHM2012 PROJECT REPORT TIR Note: This WWHM model report represents the sizing of the proposed flow control system, after adjustments to site impervious areas to reflect allowed tree credits. General Model Information WWHM2012 Project Name: Glacier-008-Tree-no-infil-sc740 Site Name: Glacier 212th Street Redevelopment Site Address: 7509 212th Street Southwest City: Edmonds Report Date: 7/30/2024 MGS Region: Puget East Data Start: 1901 /10/1 Data End: 2058/09/30 Timestep: 15 Minute DOT Data Number03 Version Date: 2023/03/31 Version: 4.2.19 POC Thresholds Low Flow Threshold for POC1: 50 Percent of the 2 Year High Flow Threshold for POC1: 50 Year Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:02 PM Page 2 Landuse Basin Data Predeveloped Land Use 7509-212th-Pre-Developed Bypass: No GroundWater: No Pervious Land Use acre C, Forest, Flat 0.77677 C, Forest, Mod 0.10576 Pervious Total 0.88253 Impervious Land Use acre Impervious Total 0 Basin Total 0.88253 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:02 PM Page 3 Mitigated Land Use 7509-212th-Developed Bypass: No GroundWater: No Pervious Land Use acre C, Forest, Flat 0.09752 C, Lawn, Flat 0.16777 Pervious Total 0.26529 Impervious Land Use acre ROOF TOPS FLAT 0.16703 DRIVEWAYS FLAT 0.35916 SIDEWALKS FLAT 0.01276 Impervious Total 0.53895 Basin Total 0.804 Note: The tabulated basin total area, as listed in Appendix A, is 0.80425-acre. The difference of 0.00001-acre is due to rounding of values. The apparent difference of 0.00001-acre equals approximately 0.44-sf, which is not significant in the calculations or modeling. Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:02 PM Page 4 Routing Elements Predeveloped Routing Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:02 PM Page 5 Mitigated Routing StormTech 30"Hx51 "W Chamber Model: 740 Dimensions Max Row Length: 206 Number of Chambers: 100 Number of Endcaps: 8 Top Stone Depth: 6 Bottom Stone Depth: 6 Discharge Structure Riser Height: 2.9 ft. Riser Diameter: 18 in. Orifice 1 Diameter: 0.464 in. Elevation:0 ft. Orifice 2 Diameter: 0.820 in. Elevation:1.734 ft. Orifice 3 Diameter: 0.580 in. Elevation:1.9 ft. Element Flows To: Outlet 1 Outlet 2 StormTech Hydraulic Table Stage(feet) Area(ac.) Volume(ac-ft.) Discharge(cfs) Infilt(cfs) 0.0000 0.077 0.000 0.000 0.000 0.0833 0.077 0.002 0.001 0.000 0.1667 0.077 0.005 0.002 0.000 0.2500 0.077 0.007 0.002 0.000 0.3333 0.077 0.010 0.003 0.000 0.4167 0.077 0.013 0.003 0.000 0.5000 0.077 0.015 0.004 0.000 0.5833 0.077 0.021 0.004 0.000 0.6667 0.077 0.026 0.004 0.000 0.7500 0.077 0.032 0.005 0.000 0.8333 0.077 0.037 0.005 0.000 0.9167 0.077 0.043 0.005 0.000 1.0000 0.077 0.048 0.005 0.000 1.0833 0.077 0.054 0.006 0.000 1.1667 0.077 0.059 0.006 0.000 1.2500 0.077 0.065 0.006 0.000 1.3333 0.077 0.070 0.006 0.000 1.4167 0.077 0.075 0.007 0.000 1.5000 0.077 0.080 0.007 0.000 1.5833 0.077 0.086 0.007 0.000 1.6667 0.077 0.091 0.007 0.000 1.7500 0.077 0.096 0.010 0.000 1.8333 0.077 0.101 0.013 0.000 1.9167 0.077 0.105 0.017 0.000 2.0000 0.077 0.110 0.020 0.000 2.0833 0.077 0.115 0.023 0.000 2.1667 0.077 0.119 0.025 0.000 2.2500 0.077 0.124 0.027 0.000 2.3333 0.077 0.128 0.029 0.000 2.4167 0.077 0.132 0.030 0.000 2.5000 0.077 0.137 0.032 0.000 2.5833 0.077 0.140 0.033 0.000 2.6667 0.077 0.144 0.035 0.000 2.7500 0.077 0.148 0.036 0.000 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:02 PM Page 6 2.8333 0.077 0.151 0.037 0.000 2.9167 0.077 0.153 0.073 0.000 3.0000 0.077 0.156 0.542 0.000 3.0833 0.077 0.159 1.277 0.000 3.1667 0.077 0.161 2.166 0.000 3.2500 0.077 0.164 3.116 0.000 3.3333 0.077 0.166 4.033 0.000 3.4167 0.077 0.169 4.831 0.000 3.5000 0.077 0.172 5.447 0.000 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:02 PM Page 7 Analysis Results POC 1 IN Percent Time Exceetlir�g om + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area: 0.88253 Total Impervious Area: 0 Mitigated Landuse Totals for POC #1 Total Pervious Area: 0.26529 Total Impervious Area: 0.53895 Flow Frequency Method: Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.014855 5 year 0.022964 10 year 0.027352 25 year 0.031808 50 year 0.034451 100 year 0.036623 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.009944 5 year 0.018651 10 year 0.027568 25 year 0.043934 50 year 0.061045 100 year 0.083641 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1902 0.021 0.011 1903 0.007 0.006 1904 0.013 0.007 1905 0.008 0.009 1906 0.003 0.006 1907 0.023 0.017 1908 0.015 0.006 1909 0.016 0.007 1910 0.026 0.020 1911 0.013 0.007 1.0 0+ 001 —1 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:02 PM Page 8 1912 0.038 0.010 1913 0.022 0.021 1914 0.005 0.006 1915 0.008 0.012 1916 0.012 0.007 1917 0.006 0.006 1918 0.014 0.015 1919 0.011 0.007 1920 0.014 0.007 1921 0.015 0.010 1922 0.016 0.017 1923 0.011 0.015 1924 0.007 0.006 1925 0.007 0.007 1926 0.013 0.006 1927 0.017 0.007 1928 0.011 0.007 1929 0.023 0.008 1930 0.014 0.007 1931 0.014 0.007 1932 0.010 0.007 1933 0.012 0.008 1934 0.033 0.029 1935 0.012 0.019 1936 0.020 0.007 1937 0.016 0.007 1938 0.016 0.007 1939 0.001 0.007 1940 0.013 0.012 1941 0.013 0.006 1942 0.020 0.030 1943 0.007 0.007 1944 0.016 0.034 1945 0.015 0.007 1946 0.013 0.006 1947 0.009 0.007 1948 0.031 0.022 1949 0.025 0.035 1950 0.013 0.007 1951 0.016 0.007 1952 0.044 0.137 1953 0.039 0.034 1954 0.012 0.011 1955 0.010 0.006 1956 0.007 0.006 1957 0.017 0.011 1958 0.041 0.036 1959 0.025 0.030 1960 0.009 0.006 1961 0.026 0.032 1962 0.013 0.007 1963 0.006 0.007 1964 0.010 0.007 1965 0.030 0.029 1966 0.005 0.007 1967 0.012 0.006 1968 0.016 0.011 1969 0.011 0.007 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:51 PM Page 9 1970 0.017 0.014 1971 0.032 0.027 1972 0.021 0.017 1973 0.024 0.030 1974 0.013 0.019 1975 0.034 0.061 1976 0.015 0.007 1977 0.010 0.007 1978 0.030 0.025 1979 0.008 0.007 1980 0.015 0.007 1981 0.015 0.010 1982 0.010 0.007 1983 0.024 0.023 1984 0.006 0.007 1985 0.014 0.008 1986 0.011 0.007 1987 0.024 0.032 1988 0.018 0.019 1989 0.014 0.007 1990 0.018 0.009 1991 0.014 0.007 1992 0.021 0.020 1993 0.017 0.008 1994 0.031 0.022 1995 0.007 0.007 1996 0.034 0.032 1997 0.016 0.007 1998 0.015 0.007 1999 0.001 0.006 2000 0.011 0.010 2001 0.008 0.006 2002 0.019 0.007 2003 0.016 0.018 2004 0.017 0.012 2005 0.018 0.007 2006 0.011 0.007 2007 0.012 0.007 2008 0.015 0.007 2009 0.010 0.007 2010 0.008 0.021 2011 0.010 0.007 2012 0.014 0.007 2013 0.011 0.007 2014 0.008 0.006 2015 0.023 0.006 2016 0.004 0.007 2017 0.024 0.030 2018 0.041 0.043 2019 0.044 0.070 2020 0.013 0.007 2021 0.020 0.024 2022 0.007 0.006 2023 0.016 0.009 2024 0.032 0.007 2025 0.013 0.009 2026 0.023 0.025 2027 0.010 0.007 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:51 PM Page 10 2028 0.005 0.006 2029 0.017 0.012 2030 0.032 0.024 2031 0.009 0.006 2032 0.007 0.006 2033 0.008 0.006 2034 0.009 0.007 2035 0.036 0.139 2036 0.019 0.012 2037 0.004 0.006 2038 0.019 0.020 2039 0.002 0.006 2040 0.007 0.007 2041 0.011 0.006 2042 0.037 0.080 2043 0.017 0.025 2044 0.023 0.016 2045 0.014 0.015 2046 0.017 0.025 2047 0.011 0.007 2048 0.015 0.007 2049 0.014 0.015 2050 0.009 0.007 2051 0.015 0.022 2052 0.009 0.007 2053 0.015 0.023 2054 0.019 0.023 2055 0.006 0.006 2056 0.006 0.007 2057 0.010 0.007 2058 0.012 0.007 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.0441 0.1388 2 0.0437 0.1368 3 0.0412 0.0803 4 0.0411 0.0697 5 0.0390 0.0606 6 0.0379 0.0428 7 0.0375 0.0365 8 0.0364 0.0352 9 0.0344 0.0342 10 0.0340 0.0337 11 0.0330 0.0320 12 0.0324 0.0320 13 0.0322 0.0317 14 0.0321 0.0301 15 0.0306 0.0300 16 0.0306 0.0297 17 0.0302 0.0295 18 0.0296 0.0293 19 0.0256 0.0286 20 0.0255 0.0270 21 0.0252 0.0251 22 0.0250 0.0251 23 0.0243 0.0246 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:51 PM Page 11 24 0.0242 0.0246 25 0.0241 0.0243 26 0.0239 0.0243 27 0.0234 0.0235 28 0.0233 0.0234 29 0.0233 0.0228 30 0.0231 0.0224 31 0.0230 0.0217 32 0.0224 0.0217 33 0.0211 0.0214 34 0.0210 0.0209 35 0.0209 0.0203 36 0.0202 0.0199 37 0.0195 0.0195 38 0.0195 0.0192 39 0.0188 0.0190 40 0.0188 0.0190 41 0.0188 0.0177 42 0.0187 0.0173 43 0.0185 0.0169 44 0.0184 0.0165 45 0.0181 0.0164 46 0.0174 0.0151 47 0.0172 0.0151 48 0.0171 0.0149 49 0.0170 0.0149 50 0.0168 0.0137 51 0.0168 0.0122 52 0.0166 0.0122 53 0.0166 0.0122 54 0.0164 0.0120 55 0.0163 0.0120 56 0.0163 0.0114 57 0.0162 0.0114 58 0.0161 0.0111 59 0.0161 0.0109 60 0.0161 0.0104 61 0.0159 0.0104 62 0.0159 0.0103 63 0.0158 0.0101 64 0.0154 0.0094 65 0.0152 0.0092 66 0.0152 0.0090 67 0.0151 0.0088 68 0.0150 0.0081 69 0.0148 0.0079 70 0.0147 0.0078 71 0.0146 0.0075 72 0.0145 0.0075 73 0.0145 0.0074 74 0.0145 0.0074 75 0.0144 0.0074 76 0.0143 0.0074 77 0.0143 0.0074 78 0.0142 0.0074 79 0.0141 0.0074 80 0.0140 0.0074 81 0.0137 0.0073 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:51 PM Page 12 82 0.0136 0.0073 83 0.0136 0.0073 84 0.0135 0.0073 85 0.0135 0.0073 86 0.0134 0.0073 87 0.0133 0.0073 88 0.0133 0.0072 89 0.0132 0.0072 90 0.0132 0.0072 91 0.0130 0.0072 92 0.0130 0.0072 93 0.0130 0.0072 94 0.0129 0.0072 95 0.0129 0.0072 96 0.0123 0.0071 97 0.0121 0.0071 98 0.0121 0.0071 99 0.0121 0.0071 100 0.0119 0.0071 101 0.0118 0.0071 102 0.0118 0.0070 103 0.0114 0.0070 104 0.0113 0.0070 105 0.0112 0.0070 106 0.0110 0.0070 107 0.0108 0.0070 108 0.0107 0.0069 109 0.0107 0.0069 110 0.0106 0.0069 111 0.0106 0.0069 112 0.0105 0.0069 113 0.0104 0.0069 114 0.0101 0.0069 115 0.0100 0.0068 116 0.0100 0.0068 117 0.0100 0.0068 118 0.0098 0.0068 119 0.0098 0.0067 120 0.0096 0.0067 121 0.0095 0.0067 122 0.0092 0.0067 123 0.0090 0.0067 124 0.0090 0.0067 125 0.0090 0.0066 126 0.0088 0.0066 127 0.0087 0.0066 128 0.0085 0.0066 129 0.0082 0.0065 130 0.0080 0.0065 131 0.0079 0.0065 132 0.0078 0.0065 133 0.0076 0.0065 134 0.0075 0.0064 135 0.0073 0.0064 136 0.0073 0.0064 137 0.0072 0.0063 138 0.0072 0.0063 139 0.0072 0.0063 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:51 PM Page 13 140 0.0072 0.0063 141 0.0070 0.0062 142 0.0068 0.0062 143 0.0066 0.0062 144 0.0063 0.0062 145 0.0062 0.0062 146 0.0061 0.0061 147 0.0059 0.0061 148 0.0058 0.0061 149 0.0054 0.0059 150 0.0052 0.0059 151 0.0050 0.0059 152 0.0041 0.0059 153 0.0036 0.0059 154 0.0034 0.0059 155 0.0016 0.0058 156 0.0010 0.0056 157 0.0008 0.0056 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:51 PM Page 14 Duration Flows The Facility PASSED Flow(cfs) Predev Mit Percentage Pass/Fail 0.0074 54269 23941 44 Pass 0.0077 50013 18007 36 Pass 0.0080 46050 17055 37 Pass 0.0082 42625 16146 37 Pass 0.0085 39466 15271 38 Pass 0.0088 36614 14429 39 Pass 0.0091 33994 13691 40 Pass 0.0093 31648 12992 41 Pass 0.0096 29578 12309 41 Pass 0.0099 27668 11709 42 Pass 0.0102 25863 11175 43 Pass 0.0104 24101 10773 44 Pass 0.0107 22543 10438 46 Pass 0.0110 21007 10058 47 Pass 0.0112 19603 9755 49 Pass 0.0115 18255 9419 51 Pass 0.0118 17066 9138 53 Pass 0.0121 16020 8863 55 Pass 0.0123 14990 8604 57 Pass 0.0126 14016 8401 59 Pass 0.0129 13118 8186 62 Pass 0.0132 12276 7971 64 Pass 0.0134 11467 7762 67 Pass 0.0137 10812 7553 69 Pass 0.0140 10212 7344 71 Pass 0.0143 9645 7118 73 Pass 0.0145 9171 6903 75 Pass 0.0148 8604 6689 77 Pass 0.0151 8164 6468 79 Pass 0.0153 7718 6259 81 Pass 0.0156 7316 6083 83 Pass 0.0159 6958 5907 84 Pass 0.0162 6595 5742 87 Pass 0.0164 6281 5577 88 Pass 0.0167 5973 5422 90 Pass 0.0170 5692 5265 92 Pass 0.0173 5434 5116 94 Pass 0.0175 5193 4980 95 Pass 0.0178 4947 4822 97 Pass 0.0181 4732 4668 98 Pass 0.0183 4526 4533 100 Pass 0.0186 4328 4398 101 Pass 0.0189 4110 4278 104 Pass 0.0192 3936 4131 104 Pass 0.0194 3775 4021 106 Pass 0.0197 3627 3902 107 Pass 0.0200 3496 3804 108 Pass 0.0203 3364 3695 109 Pass 0.0205 3261 3601 110 Pass Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:51 PM Page 15 0.0219 2789 3053 109 Pass 0.0222 2700 2944 109 Pass 0.0224 2608 2843 109 Pass 0.0227 2508 2748 109 Pass 0.0230 2412 2659 110 Pass 0.0233 2305 2555 110 Pass 0.0235 2199 2427 110 Pass 0.0238 2105 2316 110 Pass 0.0241 2016 2212 109 Pass 0.0244 1949 2125 109 Pass 0.0246 1883 2059 109 Pass 0.0249 1820 1984 109 Pass 0.0252 1747 1914 109 Pass 0.0254 1683 1851 109 Pass 0.0257 1621 1776 109 Pass 0.0260 1561 1704 109 Pass 0.0263 1498 1637 109 Pass 0.0265 1446 1557 107 Pass 0.0268 1383 1480 107 Pass 0.0271 1326 1409 106 Pass 0.0274 1269 1352 106 Pass 0.0276 1211 1300 107 Pass 0.0279 1163 1238 106 Pass 0.0282 1118 1158 103 Pass 0.0284 1079 1100 101 Pass 0.0287 1024 1040 101 Pass 0.0290 973 977 100 Pass 0.0293 935 903 96 Pass 0.0295 899 844 93 Pass 0.0298 849 779 91 Pass 0.0301 805 712 88 Pass 0.0304 772 667 86 Pass 0.0306 736 622 84 Pass 0.0309 690 577 83 Pass 0.0312 646 538 83 Pass 0.0314 611 499 81 Pass 0.0317 578 450 77 Pass 0.0320 537 419 78 Pass 0.0323 497 390 78 Pass 0.0325 445 374 84 Pass 0.0328 409 355 86 Pass 0.0331 384 338 88 Pass 0.0334 356 323 90 Pass 0.0336 326 303 92 Pass 0.0339 300 286 95 Pass 0.0342 279 269 96 Pass 0.0345 258 252 97 Pass Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:51 PM Page 16 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume: 0.0126 acre-feet On-line facility target flow: 0.0063 cfs. Adjusted for 15 min: 0.0063 cfs. Off-line facility target flow: 0.0045 cfs. Adjusted for 15 min: 0.0045 cfs. Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:51 PM Page 17 LID Report LID Technique Used for Total Volume Volume Infiltration Cumulative Percent Water Quality Percent Comment Treatment? Needs Through Volume Volume Volume Water Quality Treatment Facility (ac-ft) Infiltration Infiltrated Treated (ac-ft) (ac-ft) Credit StormTech 30'Hx51'W POC ❑ 186.46 ❑ 0.00 Total Volume Infiltrated 186.46 1 1 [i 00 0 00 0.00 0% No Treat. Credit Duration Compliance with LID Analysis Standard 8% of 2-yr to 50% of Result= 2 yr Passed Glacier-008-Tree-no-infil-sc740 7/30/2024 12:51:51 PM Page 18 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. Glacier-008-Tree-no-infil-sc740 7/30/2024 12:52:06 PM Page 19 Appendix Predeveloped Schematic 17509-� 12th-P 0.88ac Glacier-008-Tree-no-infil-sc740 7/30/2024 12:52:06 PM Page 20 Mitigated Schematic 7509-212th-C 0.80ac S �StormTech �30"Hx51 "W Glacier-008-Tree-no-infil-sc740 7/30/2024 12:52:07 PM Page 21 Predeveloped UCI File RUN GLOBAL WWHM4 model simulation START 1901 10 01 END 2058 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 Glacier-008-Tree-no-infil-sc740.wdm MESSU 25 PreGlacier-008-Tree-no-infil-sc740.MES 27 PreGlacier-008-Tree-no-infil-sc740.L61 28 PreGlacier-008-Tree-no-infil-sc740.L62 30 POeGlacier-008-Tree-no-infil-sc7401.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 10 PERLND 11 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<---------- Title ----------- >***TRAN PIVL DIG1 FIL1 1 7509-212th-Pre-Developed MAX 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 PYR DIG2 FIL2 YRND 1 2 30 9 <PLS ><------- Name ------- >NBLKS Unit -systems Printer *** # - # User t-series Engl Metr *** in out *** 10 C, Forest, Flat 1 1 1 1 27 0 11 C, Forest, Mod 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 11 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 ********* Glacier-008-Tree-no-infil-sc740 7/30/2024 12:52:07 PM Page 22 10 0 0 4 0 0 0 0 0 0 0 0 0 1 9 11 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 *** 10 0 0 0 0 0 0 0 0 0 0 0 11 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 11 0 4.5 0.08 400 0.1 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 11 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 11 0.2 0.5 0.35 6 0.5 0.7 END PWAT-PARM4 PWAT-STATEI <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 11 0 0 0 0 2.5 1 0 END PWAT-STATEI 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 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:52:07 PM Page 23 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN END IWAT-PARM3 IWAT-STATEI <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS END IWAT-STATEI END IMPLND SCHEMATIC <-Source-> <Name> # 7509-212th-Pre-Developed*** PERLND 10 PERLND 10 PERLND 11 PERLND 11 ******Routing****** END SCHEMATIC <--Area--> <-Target-> MBLK <-factor-> <Name> # Tbl# 0.77677 COPY 501 12 0.77677 COPY 501 13 0.10576 COPY 501 12 0.10576 COPY 501 13 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 Al 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 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:52:07 PM Page 24 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 DIV PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 DIV 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 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--> <Name> <Name> # #<-factor-> MASS -LINK 12 PERLND PWATER SURO 0.083333 END MASS -LINK 12 MASS -LINK 13 PERLND PWATER IFWO END MASS -LINK 13 END MASS -LINK END RUN 0.083333 <Target> <Name> COPY COPY <-Grp> <-Member->*** <Name> # #*** INPUT MEAN INPUT MEAN Glacier-008-Tree-no-infil-sc740 7/30/2024 12:52:07 PM Page 25 Mitigated UC/ File RUN GLOBAL WWHM4 model simulation START 1901 10 01 END 2058 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 Glacier-008-Tree-no-infil-sc740.wdm MESSU 25 MitGlacier-008-Tree-no-infil-sc740.MES 27 MitGlacier-008-Tree-no-infil-sc740.L61 28 MitGlacier-008-Tree-no-infil-sc740.L62 30 POCGlacier-008-Tree-no-infil-sc7401.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 10 PERLND 16 IMPLND 4 IMPLND 5 IMPLND 8 RCHRES 1 COPY 1 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<---------- Title ----------- >***TRAN PIVL DIG1 FIL1 1 StormTech 30"Hx51"W MAX 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 PYR DIG2 FIL2 YRND 1 2 30 9 <PLS ><------- Name ------- >NBLKS Unit -systems Printer *** # - # User t-series Engl Metr *** in out *** 10 C, Forest, Flat 1 1 1 1 27 0 16 C, Lawn, 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 16 0 0 1 0 0 0 0 0 0 0 0 0 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:52:07 PM Page 26 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 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 *** 10 0 0 0 0 0 0 0 0 0 0 0 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 10 0 4.5 0.08 400 0.05 0.5 0.996 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 10 0 0 2 2 0 0 0 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 *** 10 0.2 0.5 0.35 6 0.5 0.7 16 0.1 0.25 0.25 6 0.5 0.25 END PWAT-PARM4 PWAT-STATEl <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 16 0 0 0 0 2.5 1 0 END PWAT-STATEI END PERLND IMPLND GEN-INFO <PLS ><------- Name ------- > 4 ROOF TOPS/FLAT 5 DRIVEWAYS/FLAT 8 SIDEWALKS/FLAT END GEN-INFO *** Section IWATER*** Unit -systems Printer *** User t-series Engl Metr *** in out *** 1 1 1 27 0 1 1 1 27 0 1 1 1 27 0 ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 4 0 0 1 0 0 0 5 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 ********* 4 0 0 4 0 0 4 1 9 5 0 0 4 0 0 0 1 9 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:52:07 PM Page 27 8 0 0 4 0 0 0 1 9 END PRINT -INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** 4 0 0 0 0 0 5 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 4 400 0.01 0.1 0.1 5 400 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 4 0 0 5 0 0 8 0 0 END IWAT-PARM3 IWAT-STATEI <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 4 0 0 5 0 0 8 0 0 END IWAT-STATEI END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** 7509-212th-Developed*** PERLND 10 0.0975 RCHRES 1 2 PERLND 16 0.1678 RCHRES 1 2 IMPLND 4 0.167 RCHRES 1 5 IMPLND 5 0.3592 RCHRES 1 5 IMPLND 8 0.0128 RCHRES 1 5 ******Routing****** PERLND 10 0.09752 COPY 1 12 PERLND 16 0.16777 COPY 1 12 IMPLND 4 0.16703 COPY 1 15 IMPLND 5 0.35916 COPY 1 15 IMPLND 8 0.01276 COPY 1 15 RCHRES 1 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 <-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 *** Glacier-008-Tree-no-infil-sc740 7/30/2024 12:52:07 PM Page 28 # - #<------------------ >< --- > User T-series Engl Metr LKFG *** in out *** 1 StormTech 30"Hx-007 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 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 END PRINT -INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC Al 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 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 0.04 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 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 END SPEC -ACTIONS FTABLES FTABLE 1 42 4 Depth Area Volume Outflowl Velocity Travel Time*** (ft) (acres) (acre-ft) (cfs) (ft/sec) (Minutes)*** 0.000000 0.077604 0.000000 0.000000 0.083333 0.077604 0.002590 0.001687 0.166667 0.077604 0.005180 0.002385 0.250000 0.077604 0.007780 0.002921 0.333333 0.077604 0.010369 0.003373 0.416667 0.077604 0.012963 0.003771 0.500000 0.077604 0.015557 0.004131 0.583333 0.077604 0.021187 0.004462 0.666667 0.077604 0.026799 0.004770 0.750000 0.077604 0.032385 0.005060 0.833333 0.077604 0.037938 0.005333 0.916667 0.077604 0.043462 0.005594 1.000000 0.077604 0.048948 0.005842 1.083333 0.077604 0.054393 0.006081 1.166667 0.077604 0.059796 0.006311 1.250000 0.077604 0.065151 0.006532 1.333333 0.077604 0.070459 0.006746 1.416667 0.077604 0.075709 0.006954 1.500000 0.077604 0.080904 0.007156 1.583333 0.077604 0.086046 0.007352 1.666667 0.077604 0.091116 0.007543 1.750000 0.077604 0.096117 0.010037 1.833333 0.077604 0.101045 0.013662 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:52:07 PM Page 29 1.916667 0.077604 0.105893 0.017066 2.000000 0.077604 0.110660 0.020560 2.083333 0.077604 0.115347 0.023126 2.166667 0.077604 0.119936 0.025316 2.250000 0.077604 0.124390 0.027272 2.333333 0.077604 0.128720 0.029060 2.416667 0.077604 0.132933 0.030720 2.500000 0.077604 0.136999 0.032279 2.583333 0.077604 0.140896 0.033753 2.666667 0.077604 0.144587 0.035156 2.750000 0.077604 0.148005 0.036497 2.833333 0.077604 0.150981 0.037785 2.916667 0.077604 0.153792 0.073286 3.000000 0.077604 0.156454 0.542402 3.083333 0.077604 0.159044 1.277693 3.166667 0.077604 0.161634 2.166335 3.250000 0.077604 0.164234 3.116281 3.333333 0.077604 0.166824 4.033498 3.416667 0.077604 0.169418 4.831048 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 DIV PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 DIV 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 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 1 HYDR RO 1 1 1 WDM 1000 FLOW ENGL REPL RCHRES 1 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 5 IMPLND IWATER SURO 0.083333 RCHRES INFLOW IVOL END MASS -LINK 5 MASS -LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS -LINK 12 MASS -LINK 15 IMPLND IWATER SURD 0.083333 COPY INPUT MEAN END MASS -LINK 15 MASS -LINK 16 RCHRES ROFLOW COPY INPUT MEAN END MASS -LINK 16 END MASS -LINK END RUN Glacier-008-Tree-no-infil-sc740 7/30/2024 12:52:07 PM Page 30 Predeveloped HSPF Message File Glacier-008-Tree-no-infil-sc740 7/30/2024 12:52:07 PM Page 31 Mitigated HSPF Message File Glacier-008-Tree-no-infil-sc740 7/30/2024 12:52:07 PM Page 32 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. 2005-2024; 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 Glacier-008-Tree-no-infil-sc740 7/30/2024 12:52:07 PM Page 33 WWHM2012 Glacier-008-Tree-no-infil-sc740 le Edit View Help Summary Report a61 It of 51; al Fr;----- il [:%� 1 ID Basin Help SCENARIOS Predeveloped ❑ Mitioated Run Scenario Basic Elements Q®pgg a] C®® . ®t® 1 ULd Pic, Elements Commercial T oolbox IV® i. �' ova Elements ks Save xy Load xy � J Y © #I Subbasin Name: 17509.212tWie•Develaped S urface Interflow Groundwater Flows To Area in Basin F- Show Only Selected Available Pervious Acres Available Impervious Acres r A/B, Forest, Flat r ROADS/FLAT 10 r A/B, Forest, Mod r ROADS/MOD r A/B, Forest, Steep) r ROADS/STEEP 0 r A/B, Pasture, Flat 0 r ROOF TOPS/FLAT r A/B, Pasture, Mod 0 r DRIVEWAYS/FLAT r A/B, Pasture, Steep 0 r DRIVEWAYS/MOD 0 r A/B, Lawn, Flat r DRIVEWAYS/STEEP 0 r AM, Lawn, Mod 0 r SIDEWALKS/FLAT 0 r A/B, Lawn, Steep 0 r SIDEWALKS/MOD 0 r C, Forest, Flat .77677 r SIDEWALKS/STEEP r,,-o C, Forest, Mod 10576 r PARKING/FLAT r C, Forest, Steep 0 r PARKING/MOD r C, Pasture, Flat 0 r PARKING/STEEP 0 r C. Pasture, Mod 0 r POND 0 r C, Pasture, Steep 0 r Porous Pavement 0 r C, Lawn, Flat 0 r C, Lawn, Mod 0 r C, Lawn, Steep 0 r SAT, Forest, Flat 0 r SAT, Forest, Mod 0 J r— SAT, Forest, Steep Pervious Total Acres Impervious Total 0 Acres Basin Total 10.BM3 Acres Deselect Zero I Select By: GO WWHM2012 Glacier-008-Tree-no-infil-sc740 ile Edit View Help Summary Report 1 Gii;61 x ftIft iZ YJ1� 64 ® ,•li�0 0 0�&I0 � o i 9 W Fc, F P ID Bath Mp I P Schemati. nnFE-3 SCENARIOS ❑ Redeveloped 0 Mitigated Run Scenario Basic Elements JUMIN �vdmln �QWZ Fro Element<. Commercial T oolbox Move Elements �41 J rI JOB L-'y V � #I 1 l� 7509-212th-Developed Mitigated Subbasin Name:1 r' ■ ■ Designate as Bypass for PO C: Surface Interflow Groundwater Flows To IStormTech 30 Hx51'W E Area in Basin Show Only Selected Available Pervious Acres Available Impervious Acres F A/B, Forest, Flat 0 F- ROADS/FLAT 10 F- A/B, Forest, Mod 0 F ROADS/MOD 10 F- A/B, Forest, Steep 0 F ROADS/STEEP 0 r A/B, Pasture, Flat 0 Fv ROOF TOPS/FLAT 1.16703 F- A/B, Pasture, Mod 0 I✓ DRIVEWAYS/FLAT 35s16 r A/B, Pasture, Steep 0 r DRIVEWAYS/MOD 0 r A/B, Lawn, Flat 0� r DRIVEWAYS/STEEP r A/B, Lawn, Mod r SIDEWALKS/FLAT 01276 r A/B, Lawn, Steep 0 F SIDEWALKS/MOD 10 r C, Forest, Flat 09751 F SIDEWALKS/STEEP 0 r C, Forest, Mod 0 F PARKING/FLAT r C, Forest, Steep 0 r PARKING/MOD r C, Pasture, Flat 0 F PARKING/STEEP 0 r C, Pasture, Mod 0 F POND 0 r C, Pasture, Steep 0 F Porous Pavement 0 r C, Lawn, Flat 16777 r C, Lawn, Mod 0 r C, Lawn, Steep 0 r SAT, Forest, Flat 0 — I r SAT, Forest, Mod 0 F SAT, Forest, Steep 0 Pervious Total 0.26529 Acres Impervious Total 0.53895 Acres Basin Total 0.80424 Acres Deselect Zero I Select By. GO WWHM2012 PROJECT REPORT TIR Note: This WWHM model report represents the existing conditions and assumed construction conditions for use in sizing conveyance elements and TESC elements. General Model Information Project Name: Glacier-Ex-&-TESC Site Name: Glacier 212th Street Redevelopment Site Address: 7509 212th Street Southwest City: Edmonds Report Date: 2/6/2022 Gage: Everett Data Start: 1948/10/01 Data End: 2009/09/30 Timestep: 15 Minute Precip Scale: 1.000 Version Date: 2021 /07/23 Version: 4.2.18 POC Thresholds Low Flow Threshold for POC1: 50 Percent of the 2 Year High Flow Threshold for POC1: 50 Year Glacier-Ex-&-TESC 2/6/2022 6:52:09 PM Page 2 Landuse Basin Data Predeveloped Land Use 7509-212th-Existing Bypass: No GroundWater: No Pervious Land Use acre C, Forest, Flat 0.098 C, Lawn, Flat 0.516 Pervious Total 0.614 Impervious Land Use acre ROOF TOPS FLAT 0.059 DRIVEWAYS FLAT 0.195 Impervious Total 0.254 Basin Total 0.868 Element Flows To: Surface Interflow Groundwater Glacier-Ex-&-TESC 2/6/2022 6:52:09 PM Page 3 Mitigated Land Use 7509-212th-TESC Bypass: No GroundWater: No Pervious Land Use acre C, Forest, Flat 0.098 C, Lawn, Flat 0.77 Pervious Total 0.868 Impervious Land Use acre Impervious Total 0 Basin Total 0.868 Element Flows To: Surface Interflow Groundwater Glacier-Ex-&-TESC 2/6/2022 6:52:09 PM Page 4 Routing Elements Predeveloped Routing Glacier-Ex-&-TESC 2/6/2022 6:52:09 PM Page 5 Mitigated Routing Glacier-Ex-&-TESC 2/6/2022 6:52:09 PM Page 6 Analysis Results POC 1 F 0.35 )U 0.26 0 J lL 0.16 0.07 10E-5 10E-4 10E3 10E-2 10E-1 1 1r_i loll Percent Time Exceetlir�g + Predeveloped Predeveloped Landuse Totals for POC #1 Total Pervious Area- 0.614 Total Impervious Area- 0.254 Mitigated Landuse Totals for POC #1 Total Pervious Area- 0.868 Total Impervious Area- 0 1.0 0.1 001 x Mitigated Flow Frequency Method- Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.144504 5 year 0.218497 10 year 0.277433 25 year 0.364286 50 year 0.438684 100 year 0.522006 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.055064 5 year 0.118137 10 year 0.168472 25 year 0.238263 50 year 0.29306 100 year 0.349186 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 0.185 0.105 1950 0.208 0.106 1951 0.126 0.037 1952 0.134 0.052 1953 0.171 0.065 1954 0.301 0.192 1955 0.198 0.109 1956 0.076 0.029 1957 0.179 0.096 1958 0.414 0.252 Glacier-Ex-&-TESC 2/6/2022 6:52:09 PM Page 7 1959 0.123 0.046 1960 0.151 0.079 1961 0.638 0.475 1962 0.131 0.053 1963 0.249 0.152 1964 0.106 0.066 1965 0.088 0.004 1966 0.093 0.019 1967 0.224 0.053 1968 0.145 0.059 1969 0.434 0.316 1970 0.104 0.037 1971 0.184 0.088 1972 0.249 0.133 1973 0.181 0.074 1974 0.219 0.092 1975 0.185 0.090 1976 0.107 0.043 1977 0.094 0.010 1978 0.080 0.021 1979 0.249 0.160 1980 0.111 0.052 1981 0.103 0.024 1982 0.093 0.025 1983 0.177 0.088 1984 0.128 0.050 1985 0.160 0.073 1986 0.240 0.141 1987 0.165 0.042 1988 0.121 0.030 1989 0.163 0.080 1990 0.098 0.031 1991 0.104 0.021 1992 0.141 0.063 1993 0.098 0.026 1994 0.086 0.029 1995 0.090 0.031 1996 0.156 0.061 1997 0.263 0.146 1998 0.207 0.099 1999 0.081 0.010 2000 0.255 0.058 2001 0.079 0.004 2002 0.075 0.005 2003 0.101 0.009 2004 0.259 0.096 2005 0.107 0.022 2006 0.200 0.124 2007 0.178 0.084 2008 0.124 0.027 2009 0.116 0.027 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.6379 0.4754 2 0.4338 0.3161 3 0.4142 0.2523 Glacier-Ex-&-TESC 2/6/2022 6:52:36 PM Page 8 4 0.3010 0.1922 5 0.2632 0.1602 6 0.2588 0.1525 7 0.2546 0.1463 8 0.2489 0.1410 9 0.2487 0.1333 10 0.2487 0.1238 11 0.2399 0.1087 12 0.2240 0.1056 13 0.2189 0.1048 14 0.2080 0.0992 15 0.2066 0.0957 16 0.2003 0.0956 17 0.1981 0.0924 18 0.1851 0.0896 19 0.1846 0.0882 20 0.1837 0.0881 21 0.1805 0.0836 22 0.1794 0.0801 23 0.1776 0.0788 24 0.1771 0.0743 25 0.1707 0.0727 26 0.1648 0.0659 27 0.1635 0.0653 28 0.1604 0.0628 29 0.1563 0.0613 30 0.1507 0.0590 31 0.1454 0.0575 32 0.1411 0.0526 33 0.1342 0.0526 34 0.1310 0.0525 35 0.1281 0.0522 36 0.1264 0.0504 37 0.1243 0.0456 38 0.1231 0.0432 39 0.1214 0.0423 40 0.1159 0.0372 41 0.1109 0.0369 42 0.1075 0.0312 43 0.1069 0.0307 44 0.1057 0.0301 45 0.1037 0.0291 46 0.1036 0.0285 47 0.1026 0.0271 48 0.1006 0.0265 49 0.0983 0.0259 50 0.0975 0.0251 51 0.0940 0.0242 52 0.0934 0.0225 53 0.0928 0.0212 54 0.0895 0.0207 55 0.0883 0.0189 56 0.0856 0.0102 57 0.0809 0.0102 58 0.0799 0.0093 59 0.0787 0.0051 60 0.0763 0.0041 61 0.0749 0.0036 Glacier-Ex-&-TESC 2/6/2022 6:52:36 PM Page 9 Glacier-Ex-&-TESC 2/6/2022 6:52:36 PM Page 10 Duration Flows The Facility PASSED Flow(cfs) Predev Mit Percentage Pass/Fail 0.0723 920 63 6 Pass 0.0760 800 60 7 Pass 0.0797 677 54 7 Pass 0.0834 567 52 9 Pass 0.0871 500 45 9 Pass 0.0908 443 38 8 Pass 0.0945 380 36 9 Pass 0.0982 328 34 10 Pass 0.1019 291 32 10 Pass 0.1056 246 30 12 Pass 0.1093 221 27 12 Pass 0.1130 202 25 12 Pass 0.1167 185 25 13 Pass 0.1204 167 23 13 Pass 0.1241 147 19 12 Pass 0.1278 135 17 12 Pass 0.1315 124 16 12 Pass 0.1352 116 14 12 Pass 0.1389 109 13 11 Pass 0.1426 97 11 11 Pass 0.1463 90 10 11 Pass 0.1500 88 8 9 Pass 0.1537 79 6 7 Pass 0.1574 76 6 7 Pass 0.1611 71 5 7 Pass 0.1648 69 5 7 Pass 0.1685 65 5 7 Pass 0.1722 61 5 8 Pass 0.1759 58 5 8 Pass 0.1796 51 5 9 Pass 0.1833 46 5 10 Pass 0.1870 40 5 12 Pass 0.1907 38 5 13 Pass 0.1944 36 4 11 Pass 0.1981 36 4 11 Pass 0.2018 32 4 12 Pass 0.2055 29 4 13 Pass 0.2092 27 4 14 Pass 0.2129 27 4 14 Pass 0.2166 27 4 14 Pass 0.2203 24 4 16 Pass 0.2240 20 4 20 Pass 0.2277 19 4 21 Pass 0.2314 19 4 21 Pass 0.2351 18 4 22 Pass 0.2388 18 4 22 Pass 0.2425 12 4 33 Pass 0.2462 11 4 36 Pass 0.2499 8 4 50 Pass Glacier-Ex-&-TESC 2/6/2022 6:52:36 PM Page 11 0.2684 5 3 60 Pass 0.2721 5 3 60 Pass 0.2758 5 3 60 Pass 0.2795 5 3 60 Pass 0.2832 5 3 60 Pass 0.2869 5 3 60 Pass 0.2906 5 3 60 Pass 0.2943 5 3 60 Pass 0.2980 5 3 60 Pass 0.3017 5 3 60 Pass 0.3054 4 3 75 Pass 0.3091 4 3 75 Pass 0.3128 4 3 75 Pass 0.3165 4 3 75 Pass 0.3202 4 2 50 Pass 0.3239 4 2 50 Pass 0.3276 4 2 50 Pass 0.3313 4 2 50 Pass 0.3350 4 2 50 Pass 0.3387 4 2 50 Pass 0.3424 4 1 25 Pass 0.3462 4 1 25 Pass 0.3499 4 1 25 Pass 0.3536 4 1 25 Pass 0.3573 4 1 25 Pass 0.3610 4 1 25 Pass 0.3647 4 1 25 Pass 0.3684 4 1 25 Pass 0.3721 4 1 25 Pass 0.3758 4 1 25 Pass 0.3795 4 1 25 Pass 0.3832 4 1 25 Pass 0.3869 4 1 25 Pass 0.3906 4 1 25 Pass 0.3943 4 1 25 Pass 0.3980 4 1 25 Pass 0.4017 4 1 25 Pass 0.4054 4 1 25 Pass 0.4091 4 1 25 Pass 0.4128 4 1 25 Pass 0.4165 3 1 33 Pass 0.4202 3 1 33 Pass 0.4239 3 1 33 Pass 0.4276 3 1 33 Pass 0.4313 3 1 33 Pass 0.4350 2 1 50 Pass 0.4387 2 1 50 Pass Glacier-Ex-&-TESC 2/6/2022 6:52:36 PM Page 12 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume: 0.01 acre-feet On-line facility target flow: 0.005 cfs. Adjusted for 15 min: 0.005 cfs. Off-line facility target flow: 0.0034 cfs. Adjusted for 15 min: 0.0034 cfs. Glacier-Ex-&-TESC 2/6/2022 6:52:36 PM Page 13 LID Report LILTesYinique Used for Total Volume Volume Infiltration Cumulative Percent Water Quality Percent Comment Treatment? Needs Through Volume Volume Volume Water Quality Treatment Facility (ac-ft) Infiltration Infiltrated Treated (ac-ft) (ac-ft) Credit Total Volume Infiltrated 0.00 0.00 0.00 0.00 0.00 0% No Treat. Credit Duration Compliance with LID Analysis Standard 8% of 2-yr to 50% of Result = 2 yr Passed Glacier-Ex-&-TESC 2/6/2022 6:52:36 PM Page 14 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. Glacier-Ex-&-TESC 2/6/2022 6:52:43 PM Page 15 Appendix Predeveloped Schematic 17509-� 12th-E 0.87ac Glacier-Ex-&-TESC 2/6/2022 6:52:43 PM Page 16 Mitigated Schematic 7509-212th-T 1 0.87ac Glacier-Ex-&-TESC 2/6/2022 6:52:44 PM Page 17 Predeveloped UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 END GLOBAL 2009 09 30 FILES <File> <Un#> END FILES OPN SEQUENCE UNIT SYSTEM 1 <----------- File Name---- -------------------------->*** *** INGRP INDELT 00:15 PERLND 10 PERLND 16 IMPLND 4 IMPLND 5 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<---------- Title ----------- >***TRAN PIVL DIG1 FILL 1 7509-212th-Existing MAX 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 PYR DIG2 FIL2 YRND 1 2 30 9 <PLS ><------- Name ------- >NBLKS Unit -systems Printer *** # - # User t-series Engl Metr *** in out *** 10 C, Forest, Flat 1 1 1 1 27 0 16 C, Lawn, 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 16 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT -INFO Glacier-Ex-&-TESC 2/6/2022 6:52:44 PM Page 18 <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 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 *** 10 0 0 0 0 0 0 0 0 0 0 0 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 10 0 4.5 0.08 400 0.05 0.5 16 0 4.5 0.03 400 0.05 0.5 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 # - # ***PETMAX PETMIN INFEXP 10 0 0 2 16 0 0 2 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 # - # CEPSC UZSN NSUR 10 0.2 0.5 0.35 16 0.1 0.25 0.25 END PWAT-PARM4 *** INFILD DEEPFR 2 0 2 0 INTFW IRC 6 0.5 6 0.5 AGWRC 0.996 0.996 BASETP AGWETP 0 0 0 0 *** LZETP *** 0.7 0.25 PWAT-STATEl <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 16 0 0 0 0 2.5 1 0 END PWAT-STATEI END PERLND IMPLND GEN-INFO <PLS ><------- Name ------- > 4 ROOF TOPS/FLAT 5 DRIVEWAYS/FLAT END GEN-INFO *** Section IWATER*** Unit -systems Printer *** User t-series Engl Metr *** in out *** 1 1 1 27 0 1 1 1 27 0 ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 4 0 0 1 0 0 0 5 0 0 1 0 0 0 END ACTIVITY PRINT -INFO <ILS > ******** Print -flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 4 0 0 4 0 0 0 1 9 5 0 0 4 0 0 0 1 9 END PRINT -INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** Glacier-Ex-&-TESC 2/6/2022 6:52:44 PM Page 19 4 0 0 0 0 0 5 0 0 0 0 0 END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 4 400 0.01 0.1 0.1 5 400 0.01 0.1 0.1 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 4 0 0 5 0 0 END IWAT-PARM3 IWAT-STATEI <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 4 0 0 5 0 0 END IWAT-STATEI END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** 7509-212th-Existing*** PERLND 10 0.098 COPY 501 12 PERLND 10 0.098 COPY 501 13 PERLND 16 0.516 COPY 501 12 PERLND 16 0.516 COPY 501 13 IMPLND 4 0.059 COPY 501 15 IMPLND 5 0.195 COPY 501 15 ******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 Glacier-Ex-&-TESC 2/6/2022 6:52:44 PM Page 20 HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC Al 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 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 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 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 MASS -LINK 15 IMPLND IWATER SURO 0.083333 COPY INPUT MEAN END MASS -LINK 15 END MASS -LINK END RUN Glacier-Ex-&-TESC 2/6/2022 6:52:44 PM Page 21 Mitigated UC/ File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 END GLOBAL 2009 09 30 FILES <File> <Un#> END FILES OPN SEQUENCE UNIT SYSTEM 1 <----------- File Name---- -------------------------->*** *** INGRP INDELT 00:15 PERLND 10 PERLND 16 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<---------- Title ----------- >***TRAN PIVL DIG1 FIL1 1 7509-212th-TESC MAX 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 PYR DIG2 FIL2 YRND 1 2 30 9 <PLS ><------- Name ------- >NBLKS Unit -systems Printer *** # - # User t-series Engl Metr *** in out *** 10 C, Forest, Flat 1 1 1 1 27 0 16 C, Lawn, 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 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 ********* Glacier-Ex-&-TESC 2/6/2022 6:52:44 PM Page 22 10 0 0 4 0 0 0 0 0 0 0 0 0 1 9 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 *** 10 0 0 0 0 0 0 0 0 0 0 0 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 10 0 4.5 0.08 400 0.05 0.5 0.996 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 10 0 0 2 2 0 0 0 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 *** 10 0.2 0.5 0.35 6 0.5 0.7 16 0.1 0.25 0.25 6 0.5 0.25 END PWAT-PARM4 PWAT-STATEI <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 16 0 0 0 0 2.5 1 0 END PWAT-STATEI 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 Glacier-Ex-&-TESC 2/6/2022 6:52:44 PM Page 23 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN END IWAT-PARM3 IWAT-STATEI <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS END IWAT-STATEI END IMPLND SCHEMATIC <-Source-> <Name> # 7509-212th-TESC*** PERLND 10 PERLND 16 ******Routing****** END SCHEMATIC <--Area--> <-Target-> MBLK <-factor-> <Name> # Tbl# 0.098 COPY 501 12 0.77 COPY 501 12 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 Al 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 Glacier-Ex-&-TESC 2/6/2022 6:52:44 PM Page 24 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 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 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 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 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> <Name> <Name> # #<-factor-> <Name> MASS -LINK 12 PERLND PWATER SURO 0.083333 COPY END MASS -LINK 12 END MASS -LINK END RUN <-Grp> <-Member->*** <Name> # #*** INPUT MEAN Glacier-Ex-&-TESC 2/6/2022 6:52:44 PM Page 25 Predeveloped HSPF Message File Glacier-Ex-&-TESC 2/6/2022 6:52:44 PM Page 26 Mitigated HSPF Message File Glacier-Ex-&-TESC 2/6/2022 6:52:44 PM Page 27 Disclaimer Legal Notice This program and accompanying documentation is provided 'as -is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by the user. Clear Creek Solutions, Inc. disclaims 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. has been advised of the possibility of such damages. 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 Glacier-Ex-&-TESC 2/6/2022 6:52:44 PM Page 28 ccit-o APPENDIX D WATER QUALITY FACILITY SIZING TECHNICAL INFORMATION REPORT 212t" Street Site Redevelopment Edmonds, Washington CEKO PN: 22017.01 CAC EKO\ProjectslActive122017.01-Glacier-Headquarters\Engineering\TIR\2024-07-Stormwater-TI R.docx 4UiU—/1CO, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com CCMO CEKO PN: 22017.01 Project Name: Glacier 212th Street Redevelopment Page: 1 of 1 Subject: Presettling and Wet Volume Sizing (by sub -basin and total) Prepared By: CPK Date: 3/8/2024 PRE -SETTLING AND WET VOLUME SIZING CALCULATIONS References: 12019 Stormwater Management Manual for Western Washington 2019-SWMMW W 2 2022 Edmonds Stormwater Addendum 2022 ESA 3 Civil Plans CN.NN 4 Western Washington Hydrology Model 2012 WWHM2012 5 King County Surface Water Design Manual (2009) KCSWDM-2009 Pre -Settling Individual Catch Basins Sizing Calculation Procedure: Using KCSWDM, Page 6-105, Section 6.5.1.2, the presettling volume must be equal to at least 0.75 times the runoff from the mean annual storm. KCSWDM-2009 V,=(0.75xVr) Vp, = Required Presettling Volume (cf) Vr = Mean Annual Storm Runoff Volume (cf) Vr = [(0.90 x Al) +(0.25 x Atg)+(0.10 x Atf)+(0.01 x AJ] x R A; = Area of Impervious Surface (sf) A, = Area of Till Soil Covered with Grass (sf) Atf = Area of Till Soil Covered with Forest (sf) A. = Area of Outwash Soil Covered with Grass or Forest R = Rainfall from the Mean Annual Storm (ft) R = 0.054-ft, per Figure 6.4.1.A (page 6-71) No project site areas are Atf or A.. Vcb = Catch Basin Provided Presettling Volume (cf) 0 CCM40 CEKO PN: 22017.01 Project Name: Glacier 212th Street Redevelopment Page: 1 of 1 Subject: Presettling and Wet Volume Sizing (by sub -basin and total) Prepared By: CPK Date: 3/8/2024 References: PRE -SETTLING AND WET VOLUME SIZING CALCULATIONS 12019 Stormwater Management Manual for Western Washington 2 2022 Edmonds Storm water Addendum 3 Civil Plans 4 Western Washington Hydrology Model 2012 5 King County Surface Water Design Manual (2009) Presettling Sub -Basin Areas and Sizing Sub -Basin Pre -Settling CB # Total Served Area (sf) A; (sf) Atg I (sf) R (ft) Vr (cf) Vp (cf) SB-N2 CB-011 6,834 6,834 0 0.054 332 249 SB-N1 CB-010 3,986 3,986 0 0.054 194 145 SB-C CB-008 6,048 6,048 0 0.054 294 220 SB-S CB-005 3,213 3,213 0 0.054 156 117 Sub -Basin Pre -Settling CB # CB Diameter (inches) CB Unit Area (sf) CB Presettling Depth (ft) Vp (cf) V,b (cf) Check SB-N2 CB-011 72 28.3 9 249 254 OK SB-N1 CB-010 72 28.3 6 145 170 OK SB-C CB-008 72 28.3 8 220 226 1 OK SB-S CB-005 60 19.6 6 117 118 1 OK 2019-SWMMWW 2022 ESA CN.NN WWHM2012 KCS W D M-2009 Total Volume: 768 cf Required WQVolume: 0.0146 acre-feet WWHM2012 Required WQ Volume: 636 cf 64.1 WETPOND$—BASIC AND W2GE—METHODS OFANALMS FIGURE6.4.I.A PRECIPITATION FOR MEAN ANNUAL STORM IN INCHES(FEET) is a s mime. eats . __.,...e.... inches saleIO'OJ9I iabW lame location a interest 10.04]') result, generates large amounts of mnoff. For this application, fill soil types include Buckley and bedrock soils, and alluvial and outwash soils that have a seasonally high water table or are underlain at shallow depth (less (ban 5 feet) by glacial till. U.S. Soil Conservation Service (SW) hydrologic soil groups that are classified as till soils include a few B, most C, and all D soils. Sea Chapter 3 for classification of specific SCS soil types. 2009 Surface Water Design Manual I/92W9 6-71 ` Oldcastle Infrastructure" A CRN COMPANY 7000 Central Park, Suite 800 Atlanta, GA 30328 oldcastleinfrastructure.com 26 April 2024 Christopher P. Kovac, PE CEKO, LLC 2255 Squak Mountain Loop SW Issaquah, WA 98027 RE: Glacier 2121h Street Redevelopment — Edmonds, WA - BioPod"' Biofilter Sizing Dear Mr. Kovac, Oldcastle Infrastructure (Oldcastle) is pleased to provide sizing of our BioPod biofilter with StormMix'" media for the Glacier 212th Street Redevelopment in Edmonds, WA. The 2-year release rate of 0.0063 cfs was calculated by CEKO, LLC (the designer). Based on the current design conditions and the mass loading calculations for the location of the unit downstream of detention (enclosed), Oldcastle recommends a 4' x 4' BioPod Underground with internal bypass (model BPU-441B). This system has 8 square feet of media surface area and is sized to treat up to 0.029 cfs. The internal bypass can convey flows up to 5 cfs, which exceeds the peak design flow rate (0.52 cfs). The location and depth of the filtration system on the site appear to allow for adequate maintenance access and internal clearance. The BioPod has been rigorously tested in accordance with the Washington State Department of Ecology TAPE testing protocol and has General Use Level Designation approval for Basic, Enhanced and Phosphorus removal. The proposed BioPod Underground unit is sized based on the approved surface loading rate of 1.6 gpm/sf. The BioPod media profile consists of 18" StormMix Media which is located above a 6" drain rock layer and below a 2" mulch layer. The system is designed to operate with 6" ponding above the mulch layer as controlled by an orifice cap on the underdrain pipe. This results in an overall hydraulic head loss of 32"/2.67' during treatment. The design engineer is aware of the head loss and impact to the detention hydraulic calculations with affected outflow rates and volume reduction. In summary, the BioPod system appears to be a good treatment solution for this project and has been designed to operate within Oldcastle's specifications. Please note, the hydraulics of the collection system upstream or downstream of the filtration system have not been reviewed by Oldcastle. If you have any questions or require any additional information, please do not hesitate to contact me. Regards, Anna Deiters Solutions Engineer Anna.deiters@oldcastle.com 0 Oldcastle Infrastructure A CRH COMPANY Site Information Project Name Project Location Design Engineer OI Engineer Drainage Area Impervious Drainage Area (PGIS) Impervious Drainage Area (NPGIS) Pervious Area % Impervious Runoff Coefficient Flow -Based Calculations BioPod TM Downstream of Detention Sizing Summary Glacier Environmental Services - 212th Street Redevelopment Edmonds, WA CEKO, LLC - Christopher P. Kovac, P.E. Anna Deiters, PE 0.603 ac 0.603 ac 0.00 ac 0.00 ac 100% 0.95 Treatment Release Rate 0.0063 cfs Peak Release Rate (QP) 0.52 cfs Minimum Surface Area Required 1.77 square feet Mass Loadin-q Calculations Mean Annual Rainfall (P) 37 in Required % Removal 80% Required % Runoff Capture 91% Mean Annual Runoff (Vt) 70,015 cf Assumed Pollutant EMC 80 mg/L Annual Mass Load 348.88 lb Detention Pretreatment Credit 50% Media Surface Area Based on Mass Loadin Mass Removed by Pretreatment 174.44 lb Mass Load to Filter after Pretreatment 174.44 lb Required Filter Efficiency 60% Mass Removal Required 104.66 lb Mass Load per Square Foot of Media 22 Ib/sf Minimum Surface Area Required 4.76 square feet Determine Limitin_p Sizing Approach Method to Use (Flow -Based, Mass Load) Mass Loading Bypass Method Internal Summary BioPod Model BioPod Model Bypass Method Treatment Flow Capacity Bypass Capacity BPU-44 BPU-44-I B Internal 0.029 cfs 5 cfs 4/26/2024 https://oldcastle.sharepoint.com/sites/US-Stormwater-00/Shared Documents/Base/04 Projects/2022/22-702598/1 Stormwater Design/22-702598-BPU-BioPod Mass Loading Calculation-2024-0426 v2.1 DRAWING PROPERTIES Structure ID Prop. Sinl Vault Model Size 4X4 Treatment Flow Rate (cfs) 0.0063 Peak Flow Rate (cfs) 0.055 Notes: BILL OF MATERIALS ITEM STD BY INSTALL QTY UNIT DESCRIPTION/ERP ID 4.0 FT BASE X OI GC 1 EA BPU-441B-B4.0 DIVIDER WALL X 01 01 1 EA BIOPOD 4X DIVIDER WALL/BPU-4X-DW WEIR WALL X OI OI 1 EA BIOPOD 4X WEIR WALUBPU-4X-WW DRAIN ROCK X OI GC 367.57 LBS SUPER A 5000015 1 TON/SACK MEDIA X 01 GC 0.55 TON STORMMIX MEDIA, 1 TON/SACK MULCH X OI GC 1.33 CIF 3CUFT/BAG RIVERROCK X OI GC 0.01 CY ENERGY DISSIPATION STONE UNDERDRAIN KIT X 01 GC 1 EA BPU-441B-1 DRAIN DOWN X 01 GC 1 EA COMPLETE ASSEMBLY/SK-0962 TOP SLAB X OI GC 1 EA BPU-441E-TS FRAME & COVER X OI GC 1 EA 36"O/DD-OSS-36BA GRADE RflqGTST— X 01 GC 1 EA 36" 0 X 4" RIM: 418.75' 4.80' II [57.60"] III III / DIVIDER WALL, EL: 417.13'. RIM: 418.75' —TOP ELEV: 418.07' � I III EL: 415.97' 5 1 [65.4040"] III 2'-8" — BYPASS WEIR IE: 413.95' INLET, 018" OPENING — — � IE: 413.30' FOR 012" CPEP. 5"x14" INLET WINDOW, J OUTLET, 018" OPENING IE: 415.47,. FOR 012" CPEP. DRAIN DOWN UNDERDRAIN DEVICE,SK-0962 OUTLET ORIFICE LEFT END VIEW INLET, 018" OPENING FOR 012" CPEP, IE: 413.95'. DIVIDER WALL, EL: 417.13' DRAIN DOWN DEVICE,SK-0962 5'-0" 4'-0" 4" BYPASS WEIR, EL: 415.97' 4'-0" 6" TYPICAL WALL THICKNESS 1' 6" 6" 2'-0" MEDIA AREA 5"x14" INLET WINDOW, IE: 415.47' OUTLET, 018" OPENING FOR 012" CPEP, IE: 413.30'. �J 2X 1'-3" r l AAI All r-\A/ 1X 036"x4" GRADE RING. BYPASS WEIR - EL: 415.97' 10" TOP SLAB INLET, 018" OPENING FOR 012" CPEP, FARSIDE. I I COBBLES FOR ENERGY DISSIPATION. 04" SLOTTED PVC UNDERDRAIN TOP SLAB NOT SHOWN IN THIS VIEW FOR CLARITY. COVERS SHOWN IN PHANTOM 1X 036" BOLTED & GASKETED ACCESS COVER. FIELD GROUT AS NEEDED TO MEET GRADE, BY OTHERS. 4 1/4" ADJUST TO GRADE RIM: 418.75' 0.68' 1 2" MULCH T-10" ,1 DIVIDER 'i 18" StormMixTM WALL MEDIA V-7 3/4" _ 6" DRAIN ROCK OUTLET, 018" OPENING ��1' 3" 04" SLOTTED PVC UNDERDRAIN FOR 012" CPEP, NEARSIDE. TYP COBBLES FOR ENERGY DISSIPATION. DRAIN DOWN DEVICE, SK-0962. 5"x14" INLET WINDOW, IE: 415.47' ELEVATION VIEW �a 3' 5.95' [71.40"] 4'-0" 1 EL: 412.80' NOTES: 1. DESIGN LOADINGS: A. AASHTO HS-2544 (WITH IMPACT) B. DESIGN SOIL COVER: 5'-0" MAXIMUM C. ASSUMED WATER TABLE: 5' BELOW GRADE. D. LATERAL EARTH PRESSURE: 45 PCF (DRAINED) E. LATERAL LIVE LOAD SURCHARGE: 80 PSF (APPLIED TO 8'-0" BELOW GRADE) F. NO LATERAL SURCHARGE FROM ADJACENT BUILDINGS, WALLS, PIERS, OR FOUNDATIONS. 2. CONCRETE 28-DAY MINIMUM COMPRESSIVE STRENGTH: 5,000 PSI MINIMUM. 3. REINFORCING: REBAR, ASTM A615/A706, GRADE 60 4. CEMENT: ASTM C150 5. REQUIRED ALLOWABLE SOIL BEARING CAPACITY: 2,500 PSF 6. REFERENCE STANDARD: A. ASTM C890 B. ASTM C913 C. ACI318-14 7. THIS STRUCTURE IS DESIGNED PER NOTE 1. ENGINEER -OF -RECORD SHALL VERIFY THAT NOTED PARAMETERS MEET OR EXCEED PROJECT REQUIREMENTS. IF DESIGN PARAMETERS VARY FORM WHAT IS NOTED, REVIEWING ENGINEER/AUTHORITY SHALL NOTIFY OLDCASTLE INFRASTRUCTURE UPON REVIEW. 8. INLET AND OUTLET HOLES WILL BE FACTORY CORED/CAST PER PLANS AND CUSTOMER REQUIREMENTS. INLET AND OUTLET LOCATIONS CAN BE MIRRORED. 9. CONTRACTOR RESPONSIBLE TO VERIFY ALL SIZES, LOCATIONS, AND ELEVATIONS OF OPENINGS. 10. CONTRACTOR RESPONSIBLE TO ENSURE ADEQUATE BEARING SURFACE IS PROVIDED (I.E. COMPACTED AND LEVEL PER PROJECT SPECIFICATIONS). 11. SECTION HEIGHTS, SLAB/WALL THICKNESSES, AND KEYWAYS ARE SUBJECT TO CHANGE AS REQUIRED FOR SITE REQUIREMENTS AND/OR DUE TO PRODUCT AVAILABILITY AND PRODUCTION FACILITY CONSTRAINTS. 12. MAXIMUM PICK WEIGHTS: A. BASE CHARGED WITH ROCKS: 8,700 LBS 13. INTERNALS CONSIST OF UNDERDRAIN PIPE, ROCK, STORMMIX- MEDIA, MULCH, DIVIDER WALL, BYPASS WEIR AND/OR DRAIN DOWN. REFERENCE BILL OF MATERIALS FOR INSTALLATION RESPONSIBILITIES. SEE ACTIVATION GUIDE WITHIN SUBMITTAL PACKAGE FOR ADDITIONAL INSTALLATION INFORMATION. ot REV DESCRIPTION DATE 0 Oldcastle Infrastructure~ AMOOMMIIY Ph: 800.579.8819 w.vw.oldcastleinfrasirucWre.com/stonnwaler THIS DOCUMENT IS THE PROPERTY OF OLDCASTLE INFRASTRUCTURE, INC. IT IS CONFIDENTIAL, SUBMITTED FOR REFERENCE PURPOSES ONLY AND SHALL NOT BE USED IN ANY WAY INJURIOUS TO THE INTERESTS OF, OR WITHOUT THE WRITTEN PERMISSION OF OLDCASTLE INFRASTRUCTURE, INC. COPYRIGHT © 2024 OLDCASTLE INFRASTRUCTURE, INC. ALL RIGHTS RESERVED. BioPodTm Biofilter System SYSTEM Prop. Single UNDERGROUND VAULT Vault CUSTOMER: Glacier Environmental JOB NAME: JOB NUMBER: Glacier Environmental Services - 212th Site Redevelopment - Edmonds, WA 22-702598 DATE MFGLOC DRAWN I ENGINEER I CHECKED SALES ORDER 4/2/24 010-AU PPS JSA JSA - DRAWING NAME SHEET CONCEPTUAL DRAWING C4,22 ccit-o APPENDIX E CONVEYANCE CAPACITY CALCULATIONS TECHNICAL INFORMATION REPORT 212t" Street Site Redevelopment Edmonds, Washington CEKO PN: 22017.01 CAC EKO\ProjectslActive122017.01-Glacier-Headquarters\Engineering\TIR\2024-07-Stormwater-TI R.docx 4UiU—/1CO, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com CEKO PN: 22017.01 Project Name: Glacier 212th Street Redevelopment Subject: Conveyance Capacity Calculations Prepared By: CPK CONVEYANCE CAPACITY CALCULATIONS (USING MANNING EQUATION), RUNOFF FLOW RATES FROM WWHM. Run: Site Storm: 100 YEAR, 24 HOUR TOTAL RAINFALL IN INCHES: 3.2 COEFFICIENTS FOR "i" EQUATION: a= 3.2 b= 0.63 cciICly Page: 1 of Date: 3/8/2024 Location From To Inc. Area (Acre) Runoff Coef. A*C Sum A*C Time of Concen. (min.) Rain Intens (in/hr) Runoff (cfs) n Value Diam (in.) Slope (%) Length (ft) Pipe Capac (cfs) % Capac Used Veloc Full (ft/sec) Flow Time (min) Remarks CAPACITY CHECK VELOC CHECK SLOPE CHECK PARKING LOT BioPod CB-02 0.74 0.014 10 1.70 50 2.7 27.9 4.86 0.17 OK OK OK CB-02 CB-01 0.74 0.014 10 0.77 13 1.8 41.4 3.27 0.07 OK OK OK CB-01 EX. CB 1.25 0.014 12 0.27 73 1.7 72.7 2.19 0.56 OK OK OK EX. CB EX. SDMH 2.10 0.014 8 13.60 17 4.1 50.7 11.86 0.02 OK OK ANCHOR? Presettling Arch Tank 0.25 0.014 6 2.00 33 0.7 33.5 3.75 0.15 OK OK OK 416-018-001-TIR-Calculations.xlsx ManningSizing-100yr Page 1 of 1 3/11/2024 4:54 PM ccit-o APPENDIX F OPERATION AND MAINTENANCE DOCUMENTATION TECHNICAL INFORMATION REPORT 212t" Street Site Redevelopment Edmonds, Washington CEKO PN: 22017.01 CAC EKO\ProjectslActive122017.01-Glacier-Headquarters\Engineering\TIR\2024-07-Stormwater-TI R.docx 4UiU—/1CO, LLC ■ 425-864-8246 ■ 2255 Squak Mountain Loop SW ■ Issaquah, Washington 98027 ■ www.cekonw.com Appendix F: BMP Maintenance Tables Ecology intends the facility -specific maintenance standards contained in this section to be conditions for determining if maintenance actions are required as identified through inspection. Recognizing that Permittees have limited main- tenance funds and time, Ecology does not require that a Permittee perform all these maintenance activities on all their stormwater BMPs. We leave the determination of importance of each maintenance activity and its priority within the stormwater program to the Permittee. We do expect, however, that sufficient maintenance will occur to ensure that the BMPs continue to operate as designed to protect ground and surface waters. Ecology doesn't intend that these measures identify the facility's required condition at all times between inspections. In other words, exceedance of these conditions at any time between inspections and/or maintenance does not auto- matically constitute a violation of these standards. However, based upon inspection observations, the Permittee shall adjust inspection and maintenance schedules to minimize the length of time that a facility is in a condition that requires a maintenance action. Table V-A.3: Maintenance Standards - Closed Detention Systems (Tanks/Vaults) Maintenance Defect Conditions When Maintenance is Needed Results Expected When Maintenance is Per - Component formed Plugged Air Vents One-half of the cross section of a vent is blocked at any point or the vent is damaged. Vents open and functioning. Accumulated sediment depth exceeds 10% of the diameter of the storage area for 1/2 length of storage vault or any point Debris and Sediment depth exceeds 15% of diameter. All sediment and debris removed from storage (Example: 72-inch storage tank would require cleaning when sediment reaches depth of 7 inches for more than 1/2 length of area. Storage Area tank.) Any openings orvoids allowing material to be transported into facility. Joints Between Tank/Pipe Section All joint between tank/pipe sections are sealed. (Will require engineering analysis to determine structural stability). Tank Pipe Bent Out of Shape Any part of tank/pipe is bent out of shape more than 10% of its design shape. (Review required by engineerto determine Tank/pipe repaired or replaced to design. structural stability). Cracks widerthan 1/2-inch and any evidence of soil particles entering the structure through the cracks, or main- Vault replaced or repaired to design spe- Vault Structure Includes Cracks in Wall, Bottom, tenance/inspection personnel determines that the vault is not structurally sound. cifications and is structurally sound. Damage to Frame and/or Top Slab Cracks wider than 1/2-inch at the joint of any inlet/outlet pipe or any evidence of soil particles entering the vault through the No cracks more than 1/4-inch wide at the joint of walls. the inlet/outlet pipe. 2019 Stormwater Management Manual for Western Washington Volume V - Appendix Table V-A.3: Maintenance Standards - Closed Detention Systems (Tanks/Vaults) (continued) Maintenance Defect Conditions When Maintenance is Needed Results Expected When Maintenance is Per - Component formed Cover Not in Place Cover is missing or only partially in place. Any open manhole requires maintenance. Manhole is closed. Manhole Mechanism cannot be opened by one maintenance person with proper tools. Bolts into frame have less than 1/2 inch of Locking Mechanism Not Working thread (may not apply to self-locking lids). Mechanism opens with proper tools. Cover Difficult to Remove One maintenance person cannot remove lid after applying normal lifting pressure. Intent is to keep coverfrom sealing off Cover can be removed and reinstalled by one access to maintenance. maintenance person. Ladder Rungs Unsafe Ladder is unsafe due to missing rungs, misalignment, not securely attached to structure wall, rust, or cracks. Ladder meets design standards. Allows main- tenance person safe access. Catch Basins See Table V-A.5: Maintenance Standards -Catch See Table V-A.5: Maintenance Standards - Catch Basins See Table V-A.5: Maintenance Standards - Basins Catch Basins Table V-A.4: Maintenance Standards - Control Structure/Flow Restrictor Maintenance Com- Defect Condition When Maintenance is Needed Results Expected When Maintenance is Performed ponent Trash and Debris (Includes Sediment) Material exceeds 25% of sump depth or 1 foot below orifice plate. Control structure orifice is not blocked. All trash and debris removed. Structure is not securely attached to manhole wall. Structure securely attached to wall and outlet pipe. General Structure in correct position. o Structure is not in upright position (allow up to 10 /o from plumb). Structural Damage Connections to outlet pipe are not watertight and show signs of rust. Connections to outlet pipe are water tight; structure repaired or replaced and works as designed. Any holes - other than designed holes - in the structure. Structure has no holes other than designed holes. Cleanout gate is not watertight or is missing. Gate is watertight and works as designed. Gate cannot be moved up and down by one maintenance person. Gate moves up and down easily and is watertight. Cleanout Gate Damaged or Missing Chain/rod leading to gate is missing or damaged. Chain is in place and works as designed. Gate is rusted over 50% of its surface area. Gate is repaired or replaced to meet design standards. Orifice Plate Damaged or Missing Control device is not working properly due to missing, out of place, or Plate is in place and works as designed. bent orifice plate. Obstructions Any trash, debris, sediment, or vegetation blocking the plate. Plate is free of all obstructions and works as designed. Overflow Pipe Obstructions Any trash or debris blocking (or having the potential of blocking) the Pipe is free of all obstructions and works as designed. overflow pipe. Manhole See Table V-A.3: Maintenance Standards - Closed Detention Systems See Table V-A.3: Maintenance Standards - Closed Detention Systems See Table V-A.3: Maintenance Standards - Closed Detention Systems (Tank- (Tanks/Vaults) (Tanks/Vaults) s/Vaults Catch Basin See Table V-A.5: Maintenance Standards - Catch Basins See Table V-A.5: Maintenance Standards - Catch Basins See Table V-A.5: Maintenance Standards - Catch Basins 2019 Stormwater Management Manual for Western Washington Volume V - Appendix Table V-A.S: Maintenance Standards - Catch Basins Maintenance Defect Conditions When Maintenance is Needed Results Expected When Maintenance is per - Component formed Trash or debris which is located immediately in front of the catch basin opening or is blocking inletting capacity of the basin by more than 10%. No Trash or debris located immediately in front of Trash or debris (in the basin) that exceeds 60 percent of the sump depth as measured from the bottom of basin to invert of the lowest pipe into or out of the catch basin or on grate opening. basin, but in no case less than a minimum of six inches clearance from the debris surface to the invert of the lowest pipe. No trash or debris in the catch basin. Trash & Debris Trash or debris in an inlet or outlet pipe blocking more than 1/3 of its height. Y p�p 9 g Inlet and outlet pipes free of trash or debris. Dead animals or vegetation that could generate odors that could cause complaints or dangerous gases (e.g., methane). No dead animals or vegetation present within the catch basin. Sediment (in the basin) that exceeds 60 percent of the sump depth as measured from the bottom of basin to invert of the lowest pipe into or out of the Sediment basin, but in no case less than a minimum of 6 inches clearance from the sediment surface to the invert of the lowest pipe. No sediment in the catch basin General Structure Damage to To slab has holes larger than 2 square inches or cracks wider than 1/4 inch. Intent is to make sure no material is running into basin p 9 q ( g )� Top slab is free of holes and cracks. Frame and/or Top Slab Frame not sitting flush on top slab, i.e., separation of more than 3/4 inch of the frame from the top slab. Frame not securely attached Frame is sitting flush on the riser rings or top slab and firmly attached. Fractures or Cracks in Maintenance person judges that structure is unsound. Basin replaced or repaired to design standards. Basin Walls/ Bottom Grout fillet has separated or cracked widerthan 1/2 inch and longerthan 1 foot at thejoint of any inlet/outlet pipe or any evidence of soil particles entering Pipe is regrouted and secure at basin wall. catch basin through cracks. Settlement/ Mis- alignment If failure of basin has created a safety, function, or design problem. Basin replaced or repaired to design standards. Vegetation growing across and blocking more than 10% of the basin opening. No vegetation blocking opening to basin. Vegetation Vegetation growing in inlet/outlet pipe joints that is more than six inches tall and less than six inches apart. No vegetation or root growth present. Contamination and Pol- See Table V-A.1: Maintenance Standards - Detention Ponds No pollution present. lution Cover Not in Place Cover is missing or only partially in place. Any open catch basin requires maintenance. Cover/grate is in place, meets design standards, and is secured Catch Basin Locking Mechanism Mechanism cannot be opened by one maintenance person with proper tools. Bolts into frame have less than 1/2 inch of thread. Mechanism opens with proper tools. Cover Not Working Cover Difficult to One maintenance person cannot remove lid after applying normal lifting pressure. Cover can be removed by one maintenance per - Remove (Intent is keep coverfrom sealing off access to maintenance.) son. Ladder Ladder Rungs Unsafe Ladder is unsafe due to missing rungs, not securely attached to basin wall, misalignment, rust, cracks, or sharp edges. Ladder meets design standards and allows main- tenance person safe access. Grate opening Unsafe Grate with opening wider than 7/8 inch. Grate opening meets design standards. Metal Grates Trash and Debris Trash and debris that is blocking more than 20% of grate surface inletting capacity. Grate free of trash and debris. (If Applicable) Grate is in place, meets the design standards, and Damaged or Missing. Grate missing or broken member(s) of the grate. is installed and aligned with the flow path. 2019 Stormwater Management Manual for Western Washington Volume V - Appendix Table V-A.15: Maintenance Standards - Manufactured Media Filters Maintenance Component Defect Condition When Maintenance is Needed Results Expected When Maintenance is Performed Below Ground Sediment Accumulation on Media. Sediment depth exceeds 0.25-inches. No sediment deposits which would impede permeability of the compost media. Sediment Accumulation in Vault Sediment depth exceeds 6-inches in first chamber. No sediment deposits in vault bottom of first chamber. Trash/Debris Accumulation Trash and debris accumulated on compost filter bed. Trash and debris removed from the compost filter bed. Sediment in Drain Pipes/Clean-Outs When drain pipes, clean -outs, become full with sediment and/or debris. Sediment and debris removed. Damaged Pipes Any part of the pipes that are crushed or damaged due to corrosion and/or settlement. Pipe repaired and/or replaced. Access Cover Damaged/Not Working Cover cannot be opened; one person cannot open the cover using normal lifting pressure, cor- Cover repaired to proper working specifications or replaced. rosion/deformation of cover. Vault Cracks wider than 1/2-inch or evidence of soil particles entering the structure through the cracks, or main- Vault replaced or repairs made so that vault meets design spe- Vault Structure Includes Cracks in Wall, Bottom, tenance/inspection personnel determine that the vault is not structurally sound. cifications and is structurally sound. Damage to Frame and/or Top Slab Cracks wider than 1/2-inch at the joint of any inlet/outlet pipe or evidence of soil particles entering through the Vault repaired so that no cracks exist wider than 1/4-inch at the cracks. joint of the inlet/outlet pipe. Baffles Baffles corroding, cracking warping, and/or showing signs of failure as determined by maintenance/inspection Baffles repaired or replaced to specifications. person. Access Ladder Damaged Ladder is corroded or deteriorated, not functioning properly, not securely attached to structure wall, missing Ladder replaced or repaired and meets specifications, and is safe rungs, cracks, and misaligned. to use as determined by inspection personnel. Below Ground Media Drawdown of water through the media takes longer than 1 hour, and/or overflow occurs frequently. Media cartridges replaced. Cartridge Type Short Circuiting Flows do not properly enter filter cartridges. Filter cartridges replaced. Table V-A.18: Maintenance Standards - Catch Basin Inserts Maintenance Component Defect Conditions When Maintenance is Needed Results Expected When Maintenance is Performed Sediment Accumulation When sediment forms a cap overthe insert media of the insert and/or unit. No sediment cap on the insert media and its unit. Trash and Debris Accumulation Trash and debris accumulates on insert unit creating a blockage/restriction. Trash and debris removed from insert unit. Runoff freely flows into catch basin. General Media Insert Not Removing Oil Effluent waterfrom media insert has a visible sheen. Effluent waterfrom media insert is free of oils and has no visible sheen. Media Insert Water Saturated Catch basin insert is saturated with water and no longer has the capacity to absorb. Remove and replace media insert Media Insert -Oil Saturated Media oil saturated due to petroleum spill that drains into catch basin. Remove and replace media insert. Media Insert Use Beyond Product Life Media has been used beyond the typical average life of media insert product. Remove and replace media at regular intervals, depending on insert product. 2019 Stormwater Management Manual for Western Washington Volume V - Appendix