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RS_Drainage Technical Information Report_2024_11_08_v1.pdf
PRELIMINARY TECHNICAL INFORMATION REPORT FOR Jones Renton Short Plat – North CITY OF RENTON, KING COUNTY, WASHINGTON Project Manager: Flavio Bainotti Prepared by: Kathleen Byron / Jacqueline Byron Michael R Norton, P.E. Approved by: Michael Moody, P.E. Date: October 17, 2024 Core No.: 20081K 10-17-2024 Core Design, Inc. Jones Renton Short Plat – North Phase i Table of Contents SECTION 1: PROJECT OVERVIEW ..................................................................................................... 1 SECTION 2: CONDITIONS AND REQUIREMENTS SUMMARY ........................................................... 3 2.1 Core Requirements ............................................................................................................... 4 2.1.1 Core Requirement #1: Discharge at the Natural Location ............................................ 4 2.1.2 Core Requirement #2: Offsite Analysis .......................................................................... 4 2.1.3 Core Requirement #3: Flow Control Facilities ............................................................... 4 2.1.4 Core Requirement #4: Conveyance System .................................................................. 4 2.1.5 Core Requirements #5: Construction Stormwater Pollution Prevention ...................... 4 2.1.6 Core Requirement #6: Maintenance and Operations ................................................... 4 2.1.7 Core Requirement #7: Financial Guarantees and Liability ............................................ 4 2.1.8 Core Requirement #8: Water Quality ............................................................................ 4 2.1.9 Core Requirement #9: On-Site BMPs............................................................................. 4 2.2 Special Requirements ............................................................................................................ 4 2.2.1 Special Requirement #1: Other adopted Area-Specific requirements .............................. 4 2.2.2 Special Requirement #2: Flood Hazard Area Delineation .................................................. 5 2.2.3 Special Requirement #3: Flood Protection Facilities ......................................................... 5 2.2.4 Special Requirement #4: Source Control ........................................................................... 5 2.2.5 Special Requirement #5: Oil Control .................................................................................. 5 2.2.6 Special Requirement #6: Aquifer Protection Area ............................................................. 5 SECTION 3: OFFSITE ANALYSIS ......................................................................................................... 6 TASK 1 Study Area Definition and Maps ..................................................................................... 6 TASK 2 Resource Review ............................................................................................................. 6 TASK 3 Field Investigation ........................................................................................................... 6 TASK 4 Drainage System Description and Problem Description ................................................. 6 SECTION 4: FLOW CONTROL AND WATER QUALITY DESIGN .......................................................... 9 4.1 Performance Standards......................................................................................................... 9 4.2 On-Site BMPs......................................................................................................................... 9 4.3 Soils: Geotechnical Report Summary .................................................................................... 9 4.4 Flow Control: Peak Rate Flow Control Standards .............................................................. 12 Core Design, Inc. Jones Renton Short Plat – North Phase ii 4.5 Water Quality Design .......................................................................................................... 16 SECTION 5: CONVEYANCE SYSTEM ANALYSIS AND DESIGN .......................................................... 18 SECTION 6: SPECIAL REPORTS AND STUDIES ................................................................................. 19 SECTION 7: OTHER PERMITS.......................................................................................................... 20 SECTION 8: ESC ANALYSIS AND DESIGN ........................................................................................ 21 SECTION 9: BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT ...... 22 9.1 Bond Quantities .................................................................................................................. 22 9.2 Facility Summaries .............................................................................................................. 22 9.3 Declaration of Covenant ..................................................................................................... 22 SECTION 10: OPERATIONS AND MAINTENANCE ........................................................................... 23 Appendix A – Parcel & Basin Information King County Parcel Report Appendix B – Resource Review & Off-site Analysis Documentation City Zoning Map FEMA Map (53033C0664 K) City Wellhead Protection Area Map City Drainage Basin Map Flow Control Application Map Groundwater Protection Areas Map City Landslide Hazard Areas Map Appendix C – Stormwater Calculations WWHM Report Appendix D – Soils City Soils Map Geotechnical Evaluation NRCS Soils Map and Map Unit Data Core Design, Inc. Jones Renton Short Plat – North Phase Page 1 SECTION 1: PROJECT OVERVIEW The Jones Renton Short Plat – North Phase project site consists of one parcel with a total area of 0.590 acre (25,700 square feet per survey). Approximately 700 square feet (0.016 acre) will be dedicated to the City of Renton, resulting in a property encompassing 25,000 square feet (0.574 acre). The subject property is located at 3108 Park Avenue N in King County, City of Renton. The project site is bordered by Park Avenue N and single-family residences to the west, a private road and single-family residences to the east, and single-family residences to the north and south. The project site is zoned Residential (R-6) and will be developed in accordance with the applicable City of Renton Code. See Figure 1.1 at the end of this section for a vicinity map. The King County tax parcel ID number for the parcel involved is included in Table 1.1 below. (Refer to the King County parcel report included in Appendix ‘A’). Table 1.1 King County Parcel ID KC Parcel # Parcel Area (SF) 334210-3216 25,700 The project site currently contains one residential building, a shed, and a detached garage along with its associated driveway. The remaining area consists of mostly lawn, some trees (four that are significant), and a large hedge located in the north portion of the site. Access to the residence is by a paved driveway located on the parcel to the south. The proposed development of the property will include demolishing existing site improvements and subdividing the parcel into two lots, an access/utility tract, a landscape tract and a 7’ Right- of-Way dedication. The project will also include frontage improvements in Park Avenue N, which includes new asphalt pavement and constructing curb and gutter, sidewalk, and planter strip. The proposed lots will have areas of 9,215 square feet (Lot 1) and 12,857 square feet (Lot 2). Access to the lots will be provided via a 16-foot shared driveway along the south property line of Lot 1. The project site slopes downward in the north and west directions at magnitudes of 5 to 15 percent and a vertical relief of about 17 feet from approximately 218.9 to approximately 202.0. The site has a single drainage basin that drains to the north. The site is mapped as being within a moderate landslide hazard area and Wellhead Protection Area, zone 2. The project will be designed using the guidelines and requirements established in the 2022 Renton Surface Water Design Manual (RSWDM). The project is a single-family residential project that will be adding more than 7,000 square feet of new impervious area, so the project falls under Directed Drainage Review. See Section 2 for the flow chart for determining the drainage review required. The project site falls under Peak Rate Flow Control Standard which necessitates matching the developed conditions to the pre-developed conditions peak discharge rates for 2-, 10-, 100-year return periods. However, the developed peak discharge rate for the 100-Year Storm Recurrence Event decreases when compared to the existing conditions, therefore flow control facilities are not required. Water quality is not required since the project will add less than 5,000 square feet of pollution generating impervious surface (PGIS). Core Design, Inc. Jones Renton Short Plat – North Phase Page 2 Figure 1.1 Vicinity Map Core Design, Inc. Jones Renton Short Plat – North Phase Page 3 SECTION 2: CONDITIONS AND REQUIREMENTS SUMMARY The proposed project is classified as requiring “Directed Drainage Review” per Figure 1.1.2.A of the RSWDM. Therefore, all nine Core Requirements and six Special Requirements will be addressed per Section 1.2 of the RSWDM. Core Design, Inc. Jones Renton Short Plat – North Phase Page 4 2.1 Core Requirements 2.1.1 Core Requirement #1: Discharge at the Natural Location This project will match the natural discharge location towards Park Avenue N to the west and Parcels 334210-3219, 334210-3217 and 334210-3218 to the north. The site is within the West Kennydale Drainage Basin. Refer to Appendix ‘B’ of this report for West Kennydale Drainage Basin Map. 2.1.2 Core Requirement #2: Offsite Analysis This core requirement is addressed in Section 3 of this report. See Section 3 for a description of the downstream (offsite) analysis. 2.1.3 Core Requirement #3: Flow Control Facilities Per the City’s Flow Control Application Map, the site falls within the Peak Rate Flow Control area matching Existing Site Conditions (Refer to Appendix ‘B’ for the City of Renton Flow Control Application Map). The site contains one drainage basin. See Section 4 of this report for the analysis of the basin and determination of flow control facilities. 2.1.4 Core Requirement #4: Conveyance System Core Requirement #4 will be addressed during Final Design. 2.1.5 Core Requirements #5: Construction Stormwater Pollution Prevention Core Requirement #5 will be addressed during Final Design. 2.1.6 Core Requirement #6: Maintenance and Operations Core Requirement #6 will be addressed during Final Design. 2.1.7 Core Requirement #7: Financial Guarantees and Liability Core Requirement #7 will be addressed during Final Design. 2.1.8 Core Requirement #8: Water Quality This project is located within a Basic Water Quality Treatment Area. However, the project adds less than 5,000 square feet of PGIS, therefore water quality treatment is not required. 2.1.9 Core Requirement #9: On-Site BMPs The project will implement feasible flow control BMPs to mitigate the impact of storm and surface water runoff from development. Refer to Section 4 of this report for further discussion and design of proposed on-site BMPs. 2.2 Special Requirements 2.2.1 Special Requirement #1: Other adopted Area-Specific requirements Not applicable. No Area-specific requirements were found. Core Design, Inc. Jones Renton Short Plat – North Phase Page 5 2.2.2 Special Requirement #2: Flood Hazard Area Delineation The project is not located adjacent to a flood hazard area. Therefore, the site is not subject to this requirement. 2.2.3 Special Requirement #3: Flood Protection Facilities There are no levees, revetments, or berms within the project boundary. 2.2.4 Special Requirement #4: Source Control The proposed project is single family development. Source control BMPs are not required. 2.2.5 Special Requirement #5: Oil Control The project is not a commercial development nor high use site as defined in the RSDWM. Therefore, oil control BMPs will not be implemented for the project. 2.2.6 Special Requirement #6: Aquifer Protection Area The project is just inside the Five-Year Capture Zone for the PW-5A production well. Refer to Appendix ‘B’ of this report for the Groundwater Protection Areas Map Reference 15-B. In Zone 2, a liner may be required for infiltration facilities. Core Design, Inc. Jones Renton Short Plat - North Page 6 SECTION 3: OFFSITE ANALYSIS TASK 1 Study Area Definition and Maps The proposed project contains parcel number 3342103216, any upstream tributary areas and the downstream flow path of 1/4-mile. TASK 2 Resource Review Basin Reconnaissance Summary Reports No Basin Reconnaissance Summary Reports are available for the area within one quarter mile of the project site. FEMA Maps FEMA FIRMette 53033C0664G (effective 8/19/2020) indicates the site is within “Zone X” which is outside of the 500-year floodplain. The FEMA FIRMette is included in Appendix ‘B’ of this report. Sensitive Areas Folio The City of Renton Critical Areas Maps were reviewed to confirm whether the project site is located within a wetland, stream, seismic, landslide, or erosion hazard area (Critical Area Maps are included in Appendix ‘B’). The maps show the site is located within a moderate landslide hazard area. The site is also within a Zone 2 Wellhead Protection Area. Downstream Drainage Complaints Drainage complaints were researched within a quarter mile of the project site. Based on the King County GIS Drainage Complaints Map, the area downstream of the project site shows no active drainage complaints along the drainage path. TASK 3 Field Investigation Upstream Tributary Analysis The majority of any runon will occur from the north basin of the Jones Renton Short Plat project to the south, which collects and conveys most runoff to the City storm conveyance system. As such, runon is considered to be negligible. TASK 4 Drainage System Description and Problem Description Runoff from the subject property sheet flows generally northwest into Park Ave N to the west or across parcels 334210-3219, 334210-3217 or 334210-3219 to the north. That portion that flows into Park Ave N flows approximately 105 feet north in at ditch on the east side of Park Ave N to enter the City’s conveyance system at the southeast corner of Park Ave N and N 32nd St. The portion that flows across the lots to the north flows into N 32nd St then west to also enter the City’s conveyance system at the southeast corner of Park Ave N and N 32nd St, then the combined flow Core Design, Inc. Jones Renton Short Plat - North Page 7 Is conveyed north approximately 709 feet via tightline/open ditch to the northeast corner of Park Ave N and N 34th St, then Is conveyed west approximately 1,298 feet via tightline to the northeast corner of N 34th St and Burnett Ave N, then Is conveyed northwest approximately 106 feet to the conveyance system within Lake Washington Blvd N for eventual discharge into Lake Washington. The conveyance system appeared clean from all debris and blockage. No erosion was noticed. The drainage path described above encompasses the ¼ mile distance offsite. 4,800 400 Downstream Map Legend 2720136 Feet Notes 272 WGS_1984_Web_Mercator_Auxiliary_Sphere All data, information, and maps are provided "as is" without warranty or any representation of accuracy, timeliness of completeness. The burden for determining accuracy, completeness, timeliness, merchantability and fitness for or the appropriateness for use rests solely on the user. City and County Labels Parcels City and County Boundary Renton <all other values> Network Structures Public Access Riser Private Access Riser Public Inlet Private Inlet Public Manhole Private Manhole Public Utility Vault Private Utility Vault Public Clean Out Private Clean Out Public Unknown Private Unknown Pump Station Public Pump Station Private Pump Station Discharge Point Public Discharge Point Private Discharge Point Water Quality Public Water Quality Core Design, Inc. Jones Renton Short Plat - North Page 9 SECTION 4: FLOW CONTROL AND WATER QUALITY DESIGN 4.1 Performance Standards All stormwater facilities will be designed using the guidelines and requirements established in the 2022 Renton Surface Water Design Manual (RSWDM). The project is located in a Peak Rate Flow Control Standard area which allows for the existing site conditions to be modeled as the existing conditions of the site immediately prior to the proposed development. Per Section 1.2.3.1 of the RSWDM, the project is not required to provide flow control facilities because the peak flow during the 100-Year Storm Recurrence Event decreases in the Post-Developed condition when compared to the existing condition. Refer to Subsection 4.4 of this report for the basin analysis. 4.2 On-Site BMPs The project is proposing to subdivide the parcel into two (2) lots. The project site is less than five acres in size and is required to meet the Small Subdivision Project BMP Requirements per Section 1.2.9.3.1 of the 2022 RSWDM. Individual Lot BMP requirement per Section 1.2.9.2 of the RSWDM will be used to evaluate the BMP for each lot in the following order. Each lot is smaller than 22,000 square feet; thus, the Small Lot BMP Requirements will be evaluated to mitigated target impervious surface onsite to the maximum extent feasible. All sections referenced below are to be found in the RSWDM. Small Lot BMP Requirement 1. The feasibility and applicability of full dispersion as detailed in Appendix C, Section C.2.1 must be evaluated for all target impervious surfaces. If feasible and applicable, full dispersion must be implemented as part of the proposed project. Response: Full dispersion BMPs are not feasible as there is insufficient room to provide the required 100-foot flow path through native vegetation. 2. Where full dispersion of target impervious roof areas is not feasible or applicable, or will cause flooding or erosion impacts, the feasibility and applicability of full infiltration of roof runoff as detailed in Appendix C, Section C.2.2 must be evaluated. Response: Per the Draft Geotechnical Evaluation by Earth Solutions NW (ESNW), dated November 27, 2023, infiltration is feasible where cleaner sand deposits are exposed underlying low permeability layers. Full Infiltration is utilized to the maximum extent practicable for proposed rooftops on both lots. 3. All target impervious surfaces not mitigated by Requirements 1 and 2 above, must be mitigated to the maximum extent feasible using one or more BMPs from the following list. Use of a given BMP is subject to evaluation of its feasibility and applicability as detailed in Appendix C. Full Infiltration per Appendix C, Section C.2.2, or per Section 5.2, whichever is applicable. Response: Per the Draft Geotechnical Evaluation by Earth Solutions NW (ESNW), dated November 27, 2023, infiltration is feasible where cleaner sand deposits are exposed Core Design, Inc. Jones Renton Short Plat - North Page 10 underlying low permeability layers. Full Infiltration is utilized to the maximum extent practicable. Driveways are not routed to infiltration drywells due to being pollution generating and feasible onsite soils are not certain to provide soil suitability criteria for treatment. Limited Infiltration per Appendix C, Section C.2.3, Response: Per the Draft Geotechnical Evaluation by Earth Solutions NW (ESNW), dated November 27, 2023, infiltration is feasible where cleaner sand deposits are exposed underlying low permeability layers. Full Infiltration is utilized to the maximum extent practicable. Limited Infiltration BMPs are not proposed for driveways due to being pollution generating and feasible onsite soils are not certain to provide soil suitability criteria for treatment. Rain Gardens per Appendix C, Section C.2.12, sized as follows: Rain gardens have a maximum contributing area of 5,000 square feet. Rain gardens must have a minimum horizontal projected surface area below the overflow that is at least 5% of the area draining to it. Response: Due to onsite slopes and utilization of full infiltration Rain Gardens are infeasible/not applicable. Bioretention per Appendix C, Section C.2.6 Response: Due to onsite slopes and utilization of full infiltration Bioretention BMPs are infeasible/not applicable. Perméable Pavement per Appendix C, Section C.2.7 Response: Per the Draft Geotechnical Evaluation by Earth Solutions NW (ESNW), dated November 27, 2023, infiltration is feasible where cleaner sand deposits are exposed underlying low permeability layers. Full Infiltration is utilized to the maximum extent practicable. Driveways are not proposed to be permeable pavement due to being pollution generating and feasible onsite soils are not certain to provide soil suitability criteria for treatment. 4. All target impervious surfaces not mitigated by Requirements 1, 2 and 3 above, must be mitigated to the maximum extent feasible using the Basic Dispersion BMP per Appendix C, Section C.2.4 Response: Not Applicable as Full Infiltration is implemented to the maximum extent practicable. 5. BMPs must be implemented, at minimum, for an impervious area equal to at least 10% of the site/lot for site/lot sizes up to 11,000 square feet and at least 20% of the site/lot for site/lot sizes between 11,000 and 22,000 square feet. For projects located in Zone 1 of the Aquifer Protection Area, these impervious area amounts must be doubled. Response: BMPs are implemented for all proposed impervious areas on both lots. Core Design, Inc. Jones Renton Short Plat - North Page 11 6. The soil moisture holding capacity of new pervious surfaces (target pervious surfaces) must be protected in accordance with the soil amendment BMP as detailed in Appendix C, Section C.2.13 Response: The project will implement soil amendment BMP on all disturbed soils not receiving hard surfacing in the developed condition within the disturbance limits of the project. 7. Any proposed connection of roof downspouts to the local drainage system must be via a perforated pipe connection as detailed in Appendix C, Section C.2.11. Response: Not applicable 4.2.1 BMP Sizing Full Infiltration is proposed for both Lots. The project proposes to construct drywells sized to infiltrate 100% of the stormwater runoff from all proposed impervious surfacing on each lot. The drywells are designed in accordance with Section C2.2.4 of the SWDM, which states, “When located in medium sands, drywells must contain at least 90 cubic feet of gravel per 1,000 square feet of impervious surface served”. To determine the impervious surface coverage on each Lot, the lesser of the maximum allowed by RMC 4-2-110A (55% for R-6 zoning) or 4,000 square feet was chosen. For both lots, 4,000 was the lesser number. Sizing of the drywells shown here is subject to change as site layouts are developed through the Design/Approval/Permitting process. Drywell sizing is as follows: Each lot has a total maximum impervious surface area of 4,000 square feet. That means drywell storage (V1) of at least 360 cubic feet must be provided on the lot. 4,000 1,000 =𝑉ଵ 90 →𝑉ଵ = 360 𝑐𝑓 Assuming the infiltration drywells for Lots 1 and 2 have a drain rock gravel depth of 5’ (H1) the required radius, (R1), is determined as follows: 𝑉ଵ =𝜋 × (𝑅ଵ )ଶ × 𝐻ଵ 𝑅ଵ =ඨ൬ 𝑉ଵ 𝜋× 𝐻ଵ ൰ =ඨ൬ 360 𝜋× 5 ൰ = 4.8 𝑓𝑒𝑒𝑡= 5 𝑓𝑒𝑒𝑡 (𝑜𝑟 10 𝑓𝑜𝑜𝑡 𝑑𝑖𝑎𝑚𝑒𝑡𝑒𝑟) 4.3 Soils: Geotechnical Report Summary A Draft Geotechnical Evaluation for the proposed Short Plat was prepared by Earth Solutions NW, Inc., on November 27, 2023. Topsoil was observed extending to depths of approximately 6 to 12 inches below the existing ground surface (bgs). The topsoil was characterized by dark brown color and fine organic material. Underlying topsoil, native soil primarily consisted of silty sand and silt with sand (USCS: SM and ML, respectively) overlying sands with varying silt content (USCS: SP and SP-SM). The cleaner sand deposits were encountered beginning at depths of about four and one-half to six and one-half feet bgs. Native soil Core Design, Inc. Jones Renton Short Plat - North Page 12 was generally encountered in a medium dense to dense and moist condition. The maximum exploration depth was approximately 12 feet bgs. The Natural Resources Conservation Service maps site soils as: 100% Indianola Loamy Sand, 0 to 15 Percent Slopes (InC) See Appendix ‘D’ for the Geotechnical Evaluation, City of Renton Soil Map and the NRCS Soil Map and Map Unit Data 4.4 Flow Control: Peak Rate Flow Control Standards The site has a single Threshold Discharge Area (TDA) that generally drains to the northwest toward Park Avenue N to the west and Parcels 334210-3219, 334210-3217 and 334210-3218 to the north. Per Section 1.2.3.1 of the 2022 RSWDM, the project could be exempt from flow control facilities if the basin does not cause more than a 0.15 cfs increase to the 100-year peak flow rate in the developed condition compared to the 100-year peak flow rate for the existing condition. Table 4.1 indicates the Pre-Construction Land Use and associated area(s) within the clearing limits as modeled with WWHM. Note that the areas presented in all storm calculations represent the final condition after the Right-of-Way Dedication is complete. Table 4-1: Pre-Construction Land Use and Areas (WWHM Modeling) Land Cover Area (ac) C, Lawn, Flat 0.481 Rooftops/Flat 0.083 Sidewalks/Flat 0.011 Driveways/Flat 0.063 TOTAL 0.638 See Figure 4.1 for a Pre-Developed Basin Map (To be provided further in the Design/Approval/Permitting process). Core Design, Inc. Jones Renton Short Plat - North Page 13 Insert Pre-Developed Basin Map (To be provided further in the Design/Approval/Permitting process) Core Design, Inc. Jones Renton Short Plat - North Page 14 Developed Basin The developed site will consist of 2 single family residences with driveways and associated improvements. Right-of-Way improvements within the Right-of-Way Dedication mainly consist of sidewalk. The stormwater runoff from the rooftops and driveways on each lot will be directed to infiltration drywells, which are designed in accordance with Section C.2.2.4 of the RSWDM. Since these areas are fully infiltrated, they can be subtracted from the final calculations. Table 4-2 presents the Developed Land Use and Areas (Before subtraction of the roofs). See Figure 4.2 for a Developed Basin Map (To be provided further in the Design/Approval/Permitting process). Table 4-2: Developed Areas (Before Subtraction of Infiltrated Areas) Land Cover Area (ac) Modeled As Onsite: Driveway 0.079 Driveways/Mod Onsite: Roof 0.105 Rooftops/Flat Onsite: Lawn/Landscape 0.390 C, Lawn, Mod Offsite: Sidewalk 0.008 Sidewalks/Flat Offsite: Lawn/Landscape 0.013 C, Lawn, Flat Offsite: Driveway 0.009 Driveways/Mod Offsite: Road 0.034 Road/Flat TOTAL: 0.638 Table 4-3 presents the Developed Land Use and Areas (After subtraction of the roofs). Table 4-3: Developed Areas (After Subtraction of Infiltrated Areas) Land Cover Area (ac) Modeled As Onsite: Driveway 0.079 Driveways/Mod Onsite: Roof -- -- Onsite: Lawn/Landscape 0.390 C, Lawn, Flat Offsite: Sidewalk 0.008 Sidewalks/Flat Offsite: Lawn/Landscape 0.013 C, Lawn, Mod Offsite: Driveway 0.009 Driveways/Mod Offsite: Road 0.034 Road/Flat TOTAL: 0.533 Core Design, Inc. Jones Renton Short Plat - North Page 15 Insert Developed Basin Map (To be provided further in the Design/Approval/Permitting process) Core Design, Inc. Jones Renton Short Plat - North Page 16 Table 4-3 presents the Pre- and Post-Developed Peak Flows for the 2-, 10-, 25-, 50- and 100-Year Storm Recurrence Events: Table 4-3: Pre- and Post-Developed Peak Flows Recurrence Event Pre-Developed (cfs) Post-Developed (cfs) 2-Year 0.1008 0.0860 10-Year 0.1838 0.1556 25-Year 0.2334 0.1969 50-Year 0.2738 0.2305 100-Year 0.3173 0.2666 Post-Developed flows are less than Pre-Developed flows, thus a flow control facility is not required. Stormwater Calculations are Presented in Appendix ‘C’. 4.5 Water Quality Design Since the project is a single-family residential development, it is required to meet Basic water quality requirements per Section 1.2.8.1 and Figure 6.1.A (see below) of the RSWDM. However, the project could be eligible for a water quality exemption if less than 5,000 square feet of new plus replaced PGIS that is not fully dispersed will be created, and less than ¾ acre of new PGPS that is not fully dispersed will be added. Table 4-4 below lists the PGIS areas created by the project. Table 4-4: Pollution Generating Impervious Surfacing Areas Land Cover Area (sf) Lot 1 Driveway 750 Lot 2 Driveway 750 Shared Driveway 3,377 TOTAL: 4,877 The project will create less than 5,000 square feet of new plus replaced PGIS and less than 3/4 acre of new PGPS which is not fully dispersed. Therefore, the project qualifies for a water quality exemption . For the proposed infiltration facilities, a liner may be required as the project lies within Zone 2 of the Aquifer Protection Area (APA). Core Design, Inc. Jones Renton Short Plat - North Page 17 Core Design, Inc. Jones Renton Short Plat - North Page 18 SECTION 5: CONVEYANCE SYSTEM ANALYSIS AND DESIGN * This section will be provided in Final Design. Core Design, Inc. Jones Renton Short Plat - North Page 19 SECTION 6: SPECIAL REPORTS AND STUDIES Geotechnical Evaluation – Proposed Short Plat Prepared for: Jones Renton Short Plat - North Prepared by: Earth Solutions NW LLC Dated: November 27, 2023 15365 N.E. 90th Street, Suite 100 Redmond, WA 98052 Core Design, Inc. Jones Renton Short Plat - North Page 20 SECTION 7: OTHER PERMITS The following additional permits are anticipated to be required for this project: Right of Way Use Permit Demolition Permit Building Permits Core Design, Inc. Jones Renton Short Plat - North Page 21 SECTION 8: ESC ANALYSIS AND DESIGN * This Section will be provided in Final Design. Core Design, Inc. Jones Renton Short Plat - North Page 22 SECTION 9: BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT 9.1 Bond Quantities To be provided as requested by the City of Renton during Final Design. 9.2 Facility Summaries To be provided as requested by the City of Renton during Final Design. 9.3 Declaration of Covenant To be provided as requested by the City of Renton during Final Design. Core Design, Inc. Jones Renton Short Plat - North Page 23 SECTION 10: OPERATIONS AND MAINTENANCE * To be provided as needed during Final Design. Appendix A Parcel & Basin Information PARCEL Parcel Number 334210-3216 Name JONES CATHERINE+CAROLYN Site Address 3108 PARK AVE N 98056 Legal HILLMANS LK WN GARDEN OF EDEN # 1 S 100 FT OF N 200 FT BUILDING 1 Year Built 1953 Total Square Footage 1610 Number Of Bedrooms 4 Number Of Baths 2.00 Grade 7 Average Condition Average Lot Size 25700 Views Yes Waterfront TOTAL LEVY RATE DISTRIBUTION Tax Year: 2024 Levy Code: 2100 Total Levy Rate: $10.50414 Total Senior Rate: $5.39850 55.20% Voter Approved Click here to see levy distribution comparison by year. TAX ROLL HISTORY Valued Year Tax Year Appraised Land Value ($) Appraised Imps Value ($) Appraised Total ($) Appraised Imps Increase ($) Taxable Land Value ($) Taxable Imps Value ($) Taxable Total ($) 2023 2024 900,000 152,000 1,052,000 0 900,000 152,000 1,052,000 2022 2023 1,105,000 185,000 1,290,000 0 1,105,000 185,000 1,290,000 2021 2022 727,000 192,000 919,000 0 727,000 192,000 919,000 2020 2021 715,000 84,000 799,000 0 715,000 84,000 799,000 2019 2020 745,000 66,000 811,000 0 745,000 66,000 811,000 2018 2019 713,000 65,000 778,000 0 713,000 65,000 778,000 2017 2018 649,000 63,000 712,000 0 649,000 63,000 712,000 2016 2017 576,000 56,000 632,000 0 576,000 56,000 632,000 2015 2016 534,000 52,000 586,000 0 534,000 52,000 586,000 2014 2015 477,000 45,000 522,000 0 477,000 45,000 522,000 2013 2014 415,000 39,000 454,000 0 415,000 39,000 454,000 2012 2013 349,000 61,000 410,000 0 349,000 61,000 410,000 2011 2012 339,000 58,000 397,000 0 339,000 58,000 397,000 2010 2011 392,000 68,000 460,000 0 392,000 68,000 460,000 2009 2010 442,000 77,000 519,000 0 442,000 77,000 519,000 2008 2009 520,000 94,000 614,000 0 520,000 94,000 614,000 2007 2008 465,000 84,000 549,000 0 465,000 84,000 549,000 2006 2007 233,000 130,000 363,000 0 233,000 130,000 363,000 2005 2006 220,000 123,000 343,000 0 220,000 123,000 343,000 2004 2005 206,000 118,000 324,000 0 206,000 118,000 324,000 2003 2004 195,000 112,000 307,000 0 195,000 112,000 307,000 2002 2003 187,000 102,000 289,000 0 187,000 102,000 289,000 2001 2002 175,000 106,000 281,000 0 175,000 106,000 281,000 2000 2001 119,000 131,000 250,000 0 119,000 131,000 250,000 1999 2000 106,000 124,000 230,000 0 106,000 124,000 230,000 1998 1999 93,000 109,000 202,000 0 93,000 109,000 202,000 1997 1998 0 0 0 0 85,000 102,000 187,000 1996 1997 0 0 0 0 58,000 107,000 165,000 1994 1995 0 0 0 0 58,000 107,000 165,000 1992 1993 0 0 0 0 61,900 96,800 158,700 1990 1991 0 0 0 0 53,800 84,200 138,000 1988 1989 0 0 0 0 43,500 46,100 89,600 1986 1987 0 0 0 0 43,700 43,400 87,100 1984 1985 0 0 0 0 42,000 52,900 94,900 1982 1983 0 0 0 0 42,000 52,900 94,900 Appendix B Resource Review & Off-site Analysis Documentation 9,028 752 City of Renton Zoning Map This map is a user generated static output from an Internet mapping site and is for reference only. Data layers that appear on this map may or may not be accurate, current, or otherwise reliable. None 8/14/2020 Legend 5120256 THIS MAP IS NOT TO BE USED FOR NAVIGATION Feet Notes 512 WGS_1984_Web_Mercator_Auxiliary_Sphere Information Technology - GIS RentonMapSupport@Rentonwa.gov City and County Labels City and County Boundary Parcels Zoning RC-Resource Conservation R1-Residential 1 du/ac R4-Residential 4 du/ac R6-Residential - 6 DU/AC R8-Residential 8 du/ac R10-Residential 10 du/ac R14-Residential 14 du/ac RMF-Residential Multi-Family RMH-Residential Manufactured Homes CN-Commercial Neighborhood CV-Center Village CA-Commercial Arterial UC-Urban Center CD-Center Downtown COR-Commercial Office/Residential CO-Commercial Office IL-Industrial - Light IM-Industrial - Medium IH-Industrial - Heavy Overlay Districts Auto Mall A Auto Mall B National Flood Hazard Layer FIRMette 0 500 1,000 1,500 2,000250 Feet Ü SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT SPECIAL FLOOD HAZARD AREAS Without Base Flood Elevation (BFE) Zone A, V, A99 With BFE or DepthZone AE, AO, AH, VE, AR Regulatory Floodway 0.2% Annual Chance Flood Hazard, Areas of 1% annual chance flood with average depth less than one foot or with drainage areas of less than one square mileZone X Future Conditions 1% Annual Chance Flood HazardZone X Area with Reduced Flood Risk due to Levee. See Notes.Zone X Area with Flood Risk due to LeveeZone D NO SCREEN Area of Minimal Flood Hazard Zone X Area of Undetermined Flood HazardZone D Channel, Culvert, or Storm Sewer Levee, Dike, or Floodwall Cross Sections with 1% Annual Chance 17.5 Water Surface Elevation Coastal Transect Coastal Transect Baseline Profile Baseline Hydrographic Feature Base Flood Elevation Line (BFE) Effective LOMRs Limit of Study Jurisdiction Boundary Digital Data Available No Digital Data Available Unmapped This map complies with FEMA's standards for the use of digital flood maps if it is not void as described below. The basemap 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 5/3/2024 at 3:41 PM and does not reflect changes or amendments subsequent to this date 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: basemap imagery, flood zone labels, legend, scale bar, map creation date, community identifiers, FIRM panel number, and FIRM effective date. Map images for unmapped and unmodernized areas cannot be used for regulatory purposes. Legend OTHER AREAS OF FLOOD HAZARD OTHER AREAS GENERAL STRUCTURES OTHER FEATURES MAP PANELS 8 B 20.2 The pin displayed on the map is an approximate point selected by the user and does not represent an authoritative property location. 1:6,000 122°12'23"W 47°31'23"N 122°11'45"W 47°30'59"N Basemap Imagery Source: USGS National Map 2023 9,028 752 City of Renton Wellhead Protection Area This map is a user generated static output from an Internet mapping site and is for reference only. Data layers that appear on this map may or may not be accurate, current, or otherwise reliable. None 8/14/2020 Legend 5120256 THIS MAP IS NOT TO BE USED FOR NAVIGATION Feet Notes 512 WGS_1984_Web_Mercator_Auxiliary_Sphere Information Technology - GIS RentonMapSupport@Rentonwa.gov City and County Labels City and County Boundary Parcels Wellhead Protection Area Zones Zone 1 Zone 1 Modified Zone 2 Environment Designations Natural Shoreline High Intensity Shoreline Isolated High Intensity Shoreline Residential Urban Conservancy Jurisdictions Streams (Classified) <all other values> Type S Shoreline Type F Fish Type Np Non-Fish Type Ns Non-Fish Seasonal Unclassified Not Visited Wetlands Streets Parks Waterbodies 4,514 376 City of Renton Drainage Basin This map is a user generated static output from an Internet mapping site and is for reference only. Data layers that appear on this map may or may not be accurate, current, or otherwise reliable. None 8/14/2020 Legend 2560128 THIS MAP IS NOT TO BE USED FOR NAVIGATION Feet Notes 256 WGS_1984_Web_Mercator_Auxiliary_Sphere Information Technology - GIS RentonMapSupport@Rentonwa.gov City and County Labels City and County Boundary Addresses Parcels Drainage Sub Basins <all other values> Black River Boren Creek Cabbage Creek Cedar Grove Cedar Main Urban China Creek Country Creek Duamish East Fork May Creek Garrison Creek Ginger Creek Greenes Creek Gypsy Honey Creek Jenkins Creek Main Lake Kathleen Lake Washington - East Lake Washington - West Johns Creek Lake Washington South Lake Desire Shady Lake (Mud Lake) Panther Lake Lake Youngs Lake Washington B l a c k Ri v e r Gre e n Ri v e r C e darRi v er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§- ,§- ,§- q 0LOHV )ORZ&RQWURO$SSOLFDWLRQ0DS 5HIHUHQFH$ 'DWH )ORZ&RQWURO6WDQGDUGV 3HDN5DWH)ORZ&RQWURO6WDQGDUG ([LVWLQJ6LWH&RQGLWLRQV )ORZ&RQWURO'XUDWLRQ6WDQGDUG ([LVWLQJ6LWH&RQGLWLRQV )ORZ&RQWURO'XUDWLRQ6WDQGDUG )RUHVWHG&RQGLWLRQV )ORRG3UREOHP)ORZ 8QLQFRUSRUDWHG.LQJ&RXQW\)ORZ&RQWURO6WDQGDUGV 5HQWRQ&LW\/LPLWV 3RWHQWLDO$QQH[DWLRQ$UHD !!! ! ! !!!!! ! ! !! ! ! !! ! !! 3: 3: 3: 3: 3: 3: 5: 5: (: 3:$ 3: 3: ,§- ,§- WWKK33OO66(( 6:WK6W6:WK6W (D V W 9 D O O H \ 5 G (D V W 9 D O O H \ 5 G WWKK $$YYHH 66(( W K $ Y H 6 ( W K $ Y H 6 ( W K $ Y H 6 ( W K $ Y H 6 ( 7D O E R W 5 G 6 7D O E R W 5 G 6 1WK6W1WK6W W K $ Y H 6 W K $ Y H 6 5D L Q L H U $ Y H 6 5D L Q L H U $ Y H 6 6( QG6W6( QG6W 6(0D\ 9 D O O H \ 5 G 6(0D\ 9 D O O H \ 5 G (9 D O O H \ + Z \ (9 D O O H \ + Z \ 6(3 H W U R Y L W V N \ 5 G 6(3 H W U R Y L W V N \ 5 G )RUHVW ' U 6 ( )RUHVW ' U 6 ( 6WK6W6WK6W W K $ Y H 6 ( W K $ Y H 6 ( W K $ Y H 6 W K $ Y H 6 6(WK6W6(WK6W 6WK6W6WK6W 1WK6W1WK6W 1(QG6W1(QG6W 6:VW6W6:VW6W W K $ Y H 6 ( W K $ Y H 6 ( W K $ Y H 6 ( W K $ Y H 6 ( 6( QG6W6( QG6W W K $ Y H 6 ( W K $ Y H 6 ( WW KK $$YY HH 66 (( 6:WK6W6:WK6W % H Q V R Q 5 G 6 % H Q V R Q 5 G 6 + R X V H U : D \ 1 + R X V H U : D \ 1 /L Q G $ Y H 6 : /L Q G $ Y H 6 : 1WK6W1WK6W 33 XX JJ HHWW ''UU 66 (( 55HHQQWWRRQQ$$YY HH 66 6:WK6W6:WK6W , ) : < , ) : < 5 D L Q L H U $ Y H 1 5 D L Q L H U $ Y H 1 11((33DD UU NN ''UU 1(WK6W1(WK6W 6:UG6W6:UG6W 6(&DUU5G6(&DUU5G 1(UG6 W 1(UG6 W /R J D Q $ Y H 1 /R J D Q $ Y H 1 'X Y D O O $ Y H 1 ( 'X Y D O O $ Y H 1 ( , ) : < , ) : < , ) : < , ) : < ,): < ,): < , ) : < , ) : < 1(WK6W1(WK6W , ) : < , ) : < ,, ))::<< , ) : < , ) : < ,):<,):< , ) : < , ) : < ,):<,):< 1(WK6W1(WK6W % 1 , Q F % 1 , Q F % 1 , Q F % 1 , Q F %1,QF%1,QF %1 , Q F %1 , Q F % 1 , Q F % 1 , Q F %1 , Q F %1 , Q F % 1 , Q F % 1 , Q F % 1 , Q F % 1 , Q F %%11 ,,QQ FF % 1 , Q F % 1 , Q F %1 , Q F %1 , Q F %1,Q F %1,Q F %1 , Q F %1 , Q F Cedar River Green River Black River May Creek Duwamish Waterway Springbrook Creek Lake Washington Lake Youngs Panther Lake Lake Boren 5HIHUHQFH% :HOOILHOG&DSWXUH=RQHV 2QH<HDU&DSWXUH=RQH )LYH<HDU&DSWXUH=RQH 7HQ<HDU&DSWXUH=RQH &HGDU9DOOH\6ROH6RXUFH $TXLIHU3URMHFW5HYLHZ$UHD 6WUHDPIORZ6RXUFH$UHD &HGDU9DOOH\6ROH6RXUFH$TXLIHU $TXLIHU3URWHFWLRQ$UHD=RQHV =RQH =RQH0RGLILHG =RQH 1HWZRUN6WUXFWXUH !3URGXFWLRQ:HOO !6SULQJEURRN6SULQJV 5HQWRQ&LW\/LPLWV 3RWHQWLDO$QQH[DWLRQ$UHD *URXQGZDWHU3URWHFWLRQ$UHDV 'DWH q 0LOHV 4,514 376 City of Renton Landslide Hazard Area This map is a user generated static output from an Internet mapping site and is for reference only. Data layers that appear on this map may or may not be accurate, current, or otherwise reliable. None 8/14/2020 Legend 2560128 THIS MAP IS NOT TO BE USED FOR NAVIGATION Feet Notes 256 WGS_1984_Web_Mercator_Auxiliary_Sphere Information Technology - GIS RentonMapSupport@Rentonwa.gov City and County Labels City and County Boundary Addresses Parcels Landslide Very High High Moderate Unclassified Environment Designations Natural Shoreline High Intensity Shoreline Isolated High Intensity Shoreline Residential Urban Conservancy Jurisdictions Streams (Classified) <all other values> Type S Shoreline Type F Fish Type Np Non-Fish Type Ns Non-Fish Seasonal Unclassified Not Visited Wetlands Inactive Structures Appendix C Stormwater Calculations WWHM2012 PROJECT REPORT 20081K North Flow Control Minus Infiltration 10/17/2024 8:34:33 AM Page 2 General Model Information WWHM2012 Project Name:20081K North Flow Control Minus Infiltration Site Name:Jones Short Plat North Site Address: City:Renton Report Date:10/17/2024 Gage:Seatac Data Start:1948/10/01 Data End:2009/09/30 Timestep:15 Minute Precip Scale:1.000 Version Date:2023/01/27 Version:4.2.19 POC Thresholds Low Flow Threshold for POC1:50 Percent of the 2 Year High Flow Threshold for POC1:50 Year 20081K North Flow Control Minus Infiltration 10/17/2024 8:34:34 AM Page 3 Landuse Basin Data Predeveloped Land Use Existing Conditions Bypass:No GroundWater:No Pervious Land Use acre C, Lawn, Mod 0.481 Pervious Total 0.481 Impervious Land Use acre ROOF TOPS FLAT 0.083 DRIVEWAYS FLAT 0.063 SIDEWALKS FLAT 0.011 Impervious Total 0.157 Basin Total 0.638 20081K North Flow Control Minus Infiltration 10/17/2024 8:34:34 AM Page 4 Mitigated Land Use Developed Conditions Bypass:No GroundWater:No Pervious Land Use acre C, Lawn, Mod 0.403 Pervious Total 0.403 Impervious Land Use acre ROADS FLAT 0.009 ROADS MOD 0.034 ROADS FLAT 0.079 SIDEWALKS FLAT 0.008 Impervious Total 0.13 Basin Total 0.533 20081K North Flow Control Minus Infiltration 10/17/2024 8:34:34 AM Page 5 Routing Elements Predeveloped Routing 20081K North Flow Control Minus Infiltration 10/17/2024 8:34:34 AM Page 6 Mitigated Routing 20081K North Flow Control Minus Infiltration 10/17/2024 8:34:34 AM Page 7 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area:0.481 Total Impervious Area:0.157 Mitigated Landuse Totals for POC #1 Total Pervious Area:0.403 Total Impervious Area:0.13 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.100807 5 year 0.148324 10 year 0.183834 25 year 0.233405 50 year 0.273824 100 year 0.317301 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.086048 5 year 0.125934 10 year 0.155623 25 year 0.196937 50 year 0.230532 100 year 0.266593 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 0.166 0.141 1950 0.164 0.139 1951 0.097 0.082 1952 0.058 0.049 1953 0.053 0.046 1954 0.081 0.069 1955 0.085 0.073 1956 0.082 0.072 1957 0.117 0.098 1958 0.071 0.061 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:04 AM Page 8 1959 0.057 0.050 1960 0.103 0.088 1961 0.090 0.075 1962 0.058 0.049 1963 0.092 0.079 1964 0.077 0.067 1965 0.124 0.104 1966 0.063 0.054 1967 0.162 0.135 1968 0.139 0.120 1969 0.111 0.093 1970 0.093 0.079 1971 0.114 0.097 1972 0.154 0.129 1973 0.053 0.045 1974 0.117 0.100 1975 0.122 0.103 1976 0.087 0.074 1977 0.079 0.068 1978 0.095 0.084 1979 0.097 0.084 1980 0.192 0.167 1981 0.096 0.081 1982 0.182 0.152 1983 0.098 0.086 1984 0.071 0.059 1985 0.097 0.081 1986 0.096 0.081 1987 0.102 0.086 1988 0.051 0.043 1989 0.063 0.059 1990 0.306 0.256 1991 0.215 0.182 1992 0.074 0.064 1993 0.051 0.043 1994 0.043 0.037 1995 0.083 0.070 1996 0.146 0.126 1997 0.113 0.095 1998 0.089 0.077 1999 0.242 0.206 2000 0.104 0.087 2001 0.077 0.067 2002 0.156 0.131 2003 0.132 0.115 2004 0.216 0.185 2005 0.095 0.079 2006 0.092 0.077 2007 0.281 0.236 2008 0.208 0.175 2009 0.124 0.105 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.3058 0.2560 2 0.2805 0.2358 3 0.2419 0.2059 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:04 AM Page 9 4 0.2159 0.1850 5 0.2152 0.1822 6 0.2079 0.1747 7 0.1915 0.1669 8 0.1817 0.1520 9 0.1665 0.1410 10 0.1645 0.1387 11 0.1621 0.1352 12 0.1565 0.1306 13 0.1542 0.1290 14 0.1460 0.1260 15 0.1385 0.1204 16 0.1317 0.1149 17 0.1239 0.1051 18 0.1237 0.1037 19 0.1224 0.1027 20 0.1172 0.0996 21 0.1167 0.0984 22 0.1136 0.0968 23 0.1130 0.0950 24 0.1113 0.0934 25 0.1038 0.0876 26 0.1026 0.0875 27 0.1020 0.0865 28 0.0979 0.0860 29 0.0975 0.0841 30 0.0974 0.0839 31 0.0968 0.0821 32 0.0965 0.0812 33 0.0955 0.0811 34 0.0954 0.0807 35 0.0947 0.0793 36 0.0933 0.0791 37 0.0922 0.0787 38 0.0918 0.0775 39 0.0901 0.0774 40 0.0886 0.0749 41 0.0866 0.0744 42 0.0845 0.0728 43 0.0829 0.0723 44 0.0821 0.0700 45 0.0811 0.0688 46 0.0788 0.0682 47 0.0772 0.0674 48 0.0766 0.0674 49 0.0739 0.0641 50 0.0711 0.0606 51 0.0710 0.0593 52 0.0635 0.0592 53 0.0631 0.0545 54 0.0581 0.0500 55 0.0576 0.0491 56 0.0565 0.0488 57 0.0535 0.0461 58 0.0533 0.0448 59 0.0512 0.0432 60 0.0507 0.0430 61 0.0426 0.0373 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:04 AM Page 10 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:04 AM Page 11 Duration Flows The Facility PASSED Flow(cfs)Predev Mit Percentage Pass/Fail 0.0504 1175 646 54 Pass 0.0527 1011 570 56 Pass 0.0549 885 505 57 Pass 0.0572 769 458 59 Pass 0.0594 662 403 60 Pass 0.0617 594 352 59 Pass 0.0639 536 318 59 Pass 0.0662 485 289 59 Pass 0.0685 443 266 60 Pass 0.0707 397 238 59 Pass 0.0730 360 217 60 Pass 0.0752 330 194 58 Pass 0.0775 300 177 58 Pass 0.0797 277 161 58 Pass 0.0820 257 146 56 Pass 0.0843 236 133 56 Pass 0.0865 218 117 53 Pass 0.0888 200 110 55 Pass 0.0910 184 104 56 Pass 0.0933 168 97 57 Pass 0.0955 154 91 59 Pass 0.0978 140 87 62 Pass 0.1001 131 82 62 Pass 0.1023 120 79 65 Pass 0.1046 112 75 66 Pass 0.1068 105 67 63 Pass 0.1091 103 64 62 Pass 0.1113 96 59 61 Pass 0.1136 92 54 58 Pass 0.1158 89 48 53 Pass 0.1181 83 47 56 Pass 0.1204 81 46 56 Pass 0.1226 78 43 55 Pass 0.1249 73 42 57 Pass 0.1271 70 38 54 Pass 0.1294 62 36 58 Pass 0.1316 57 35 61 Pass 0.1339 55 33 60 Pass 0.1362 51 28 54 Pass 0.1384 48 27 56 Pass 0.1407 45 25 55 Pass 0.1429 45 24 53 Pass 0.1452 44 22 50 Pass 0.1474 41 21 51 Pass 0.1497 39 21 53 Pass 0.1520 39 19 48 Pass 0.1542 38 17 44 Pass 0.1565 36 17 47 Pass 0.1587 32 17 53 Pass 0.1610 32 16 50 Pass 0.1632 28 15 53 Pass 0.1655 27 15 55 Pass 0.1678 25 12 48 Pass 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:04 AM Page 12 0.1700 23 12 52 Pass 0.1723 23 11 47 Pass 0.1745 22 11 50 Pass 0.1768 21 10 47 Pass 0.1790 20 9 45 Pass 0.1813 19 8 42 Pass 0.1836 17 7 41 Pass 0.1858 17 6 35 Pass 0.1881 17 5 29 Pass 0.1903 17 5 29 Pass 0.1926 15 5 33 Pass 0.1948 13 4 30 Pass 0.1971 13 4 30 Pass 0.1994 13 3 23 Pass 0.2016 13 3 23 Pass 0.2039 12 3 25 Pass 0.2061 12 2 16 Pass 0.2084 10 2 20 Pass 0.2106 9 2 22 Pass 0.2129 8 2 25 Pass 0.2151 8 2 25 Pass 0.2174 5 2 40 Pass 0.2197 5 2 40 Pass 0.2219 5 2 40 Pass 0.2242 5 2 40 Pass 0.2264 5 2 40 Pass 0.2287 4 2 50 Pass 0.2309 4 2 50 Pass 0.2332 4 2 50 Pass 0.2355 3 2 66 Pass 0.2377 3 1 33 Pass 0.2400 3 1 33 Pass 0.2422 2 1 50 Pass 0.2445 2 1 50 Pass 0.2467 2 1 50 Pass 0.2490 2 1 50 Pass 0.2513 2 1 50 Pass 0.2535 2 1 50 Pass 0.2558 2 1 50 Pass 0.2580 2 0 0 Pass 0.2603 2 0 0 Pass 0.2625 2 0 0 Pass 0.2648 2 0 0 Pass 0.2671 2 0 0 Pass 0.2693 2 0 0 Pass 0.2716 2 0 0 Pass 0.2738 2 0 0 Pass 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:04 AM Page 13 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume:0 acre-feet On-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. Off-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:04 AM Page 14 LID Report 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:25 AM Page 15 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. 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:25 AM Page 16 Appendix Predeveloped Schematic 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:29 AM Page 17 Mitigated Schematic 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:34 AM Page 18 Predeveloped UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 20081K North Flow Control Minus Infiltration.wdm MESSU 25 Pre20081K North Flow Control Minus Infiltration.MES 27 Pre20081K North Flow Control Minus Infiltration.L61 28 Pre20081K North Flow Control Minus Infiltration.L62 30 POC20081K North Flow Control Minus Infiltration1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 17 IMPLND 4 IMPLND 5 IMPLND 8 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Existing Conditions MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 17 C, Lawn, 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 *** 17 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 ********* 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:34 AM Page 19 17 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 *** 17 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 17 0 4.5 0.03 400 0.1 0.5 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 17 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 17 0.1 0.25 0.25 6 0.5 0.25 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 17 0 0 0 0 2.5 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 4 ROOF TOPS/FLAT 1 1 1 27 0 5 DRIVEWAYS/FLAT 1 1 1 27 0 8 SIDEWALKS/FLAT 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 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 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 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:34 AM Page 20 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-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 4 0 0 5 0 0 8 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Existing Conditions*** PERLND 17 0.481 COPY 501 12 PERLND 17 0.481 COPY 501 13 IMPLND 4 0.083 COPY 501 15 IMPLND 5 0.063 COPY 501 15 IMPLND 8 0.011 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 HYDR-PARM1 RCHRES Flags for each HYDR Section *** 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:34 AM Page 21 # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1 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 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:34 AM Page 22 Mitigated UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 20081K North Flow Control Minus Infiltration.wdm MESSU 25 Mit20081K North Flow Control Minus Infiltration.MES 27 Mit20081K North Flow Control Minus Infiltration.L61 28 Mit20081K North Flow Control Minus Infiltration.L62 30 POC20081K North Flow Control Minus Infiltration1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 17 IMPLND 1 IMPLND 2 IMPLND 8 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Developed Conditions MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 17 C, Lawn, 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 *** 17 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 ********* 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:34 AM Page 23 17 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 *** 17 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 17 0 4.5 0.03 400 0.1 0.5 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 17 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 17 0.1 0.25 0.25 6 0.5 0.25 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 17 0 0 0 0 2.5 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 1 ROADS/FLAT 1 1 1 27 0 2 ROADS/MOD 1 1 1 27 0 8 SIDEWALKS/FLAT 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 1 0 0 1 0 0 0 2 0 0 1 0 0 0 8 0 0 1 0 0 0 END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 1 0 0 4 0 0 4 1 9 2 0 0 4 0 0 0 1 9 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 *** 1 0 0 0 0 0 2 0 0 0 0 0 8 0 0 0 0 0 END IWAT-PARM1 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:34 AM Page 24 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 1 400 0.01 0.1 0.1 2 400 0.05 0.1 0.08 8 400 0.01 0.1 0.1 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 1 0 0 2 0 0 8 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 1 0 0 2 0 0 8 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Developed Conditions*** PERLND 17 0.403 COPY 501 12 PERLND 17 0.403 COPY 501 13 IMPLND 1 0.009 COPY 501 15 IMPLND 2 0.034 COPY 501 15 IMPLND 1 0.079 COPY 501 15 IMPLND 8 0.008 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 HYDR-PARM1 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:34 AM Page 25 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1 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> <-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 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:34 AM Page 26 Predeveloped HSPF Message File 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:34 AM Page 27 Mitigated HSPF Message File 20081K North Flow Control Minus Infiltration 10/17/2024 8:35:34 AM Page 28 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 Appendix D Soils BeD BeD BeC AkF AmC KpD AmB AmB AgC AgC AgC KpB AgC AkF BeD AgC KpD AgCKpBKpBAgD EvC Bh BeC AgB KpB AgD UrEwC EvB AmC Or AgC BeC BeD BeD BeC AgC KpD BeC KpCKpB Sk AmC BeC UrBeCUr AgD KpB Ur AgC EvC KpC AgC OvD SkAgB AgB AgD EvC W OvD OvD No AgC AgD EvC RdC Sk KpB No AgC RdEAgCEvC BeC InC Bh BeD RdC AkF AgD BeD BhSm AgC RdE AgC AgDEvC Sh Sh PITS PyAgC AgD AgC EvC PITS EvB BeC OvC PITS EvB AgC InA AgD AgD Ur Bh AgC RdCEvCEvD AmB AmC AgD BeD EvC AkF AgD AgC Sm AgD AmC EvB AgD Sm AgC EwC PITSPu Bh Bh AgC KpD Tu AgC EvC EvC Ur RdC KpB RdCRdE W AgD AgD No AgB AgC No An AkF EvB InD AgD EvD InC Sk BeC PITS Ur WBeC W BeD An EvC BeC Pc EvC Rh AmC BeCBeD BeD Ur BeC Ur W W Rh EvC AkF PITS AgD AmCPITS Wo Py Tu BeD EvB Py AmC Py An InC Ng AgC AgC W EvB AgD AgCWo Ur W Ur RdC Ur Ur EvC Rh Pc PyPy AgD AmC AgD MaRh Pc BeD Py Ng AmC Ng BeC AgC Rh AgD Py Ma PyRh RhRhPu Pu Ur Pu PITS BeD Rh EvC Py Wo Wo AgC Ma AgD AgB So Ng AgD Tu Py AgC AgC AgC AgC Ng Ur AgD Sk AmB AgB AgD PuUr Py Sk Ur No AgB MaBeC W AkFBeD Pu Py No No AmC AgC EvC Ma Sk EvC AgB Py InC SkAmC AmC AgC AgB SkAgB PITS AgC No Pu AmB EvC PITS AmB AgB AkF AkF Ng AgD AgD AgB EvBAmB AmC AmC Wo Ng PITS Nk AgD SkNk SkAgB Ur AgD Wo AmC No AgD No Ur AgB Ur Br Py Os So EvB Ur Nk Wo AmB W Pc OsRe UrAmB Sk W AmC Tu No Pu AgD AmBAkFAgCNo UrPk AgB AgC Ur AmB NoAmC NoAmC AmB PITS UrSkAgCAgB AgC Re AgB W InC No AgC Wo EvC NoAmC Wo AgB AgB Ur Ng SkAmB ReOs AgC No AgD No Ur No InC AgD EvC Tu AmB EvB AgD Pu InC EvCAmC NoEvC Ur EvB AkF Br Os AgD AmC AgB AgD AmB Os Os NoAmC Pk AkF No AmC EvC NoNo AgDBr AgBAgC AgBAmC Re Re KpBAmBNoPyPySkNgAgBEvC EvC Sk NoEvBNo Pu BrPuOsOsWo AmC Panther Lake Lake Youngs Lake Washington B l a c k Ri v e r Gr e e n R iver Ceda r River Duwa mish W a t erway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§- ,§- 5HIHUHQFH& 5HQWRQ&LW\/LPLWV 3RWHQWLDO$QQH[DWLRQ$UHD *URXQGZDWHU3URWHFWLRQ$UHD%RXQGDU\ $TXLIHU3URWHFWLRQ$UHD=RQH $TXLIHU3URWHFWLRQ$UHD=RQH0RGLILHG 6RLO7\SH $J% $J& $J' $N) $P% $P& $Q %H& %H' %K %U (Y% (Y& (Y' (Z& ,Q$ ,Q& ,Q' .S% .S& .S' 0D 1J 1N 1R 2U 2V 2Y& 2Y' 3,76 3F 3N 3X 3\ 5G& 5G( 5H 5K 6K 6N 6P 6R 7X 8U : :R 'DWH 0LOHVq6RLO6XUYH\ 15365 N.E. 90th Street, Suite 100 • Redmond, WA 98052 • (425) 449-4704 • FAX (425) 449-4711 Earth Solutions NW LLC Geotechnical Engineering, Construction Observation/Testing and Environmental Services November 27, 2023 ES-9475 Park AVE 5, LLC 3412 – 210th Place Northeast Sammamish, Washington 98074 Attention: Kevin Rech Subject: Geotechnical Evaluation Proposed Short Plat 3108 Park Avenue North Renton, Washington Dear Kevin: As requested, Earth Solutions NW, LLC (ESNW) has prepared this geotechnical evaluation for the subject site. We performed our work in general accordance with the scope of services outlined in our proposal PES-9475, which was authorized by you on September 20, 2023. A summary of the subsurface exploration and pertinent geotechnical recommendations for site development are provided in this letter. Based on our evaluation, the proposed project is feasible from a geotechnical standpoint. Project Description We understand the project will include construction of several new single-family residential structures and related infrastructure improvements. We assume the proposed residential structures will be two to three stories in height and constructed utilizing relatively lightly loaded wood framing supported on conventional continuous and spread footing foundations. We anticipate perimeter footing loads of about 1 to 2 kips per linear foot, column loads of up to 20 kips, and slab-on-grade loading of roughly 150 pounds per square foot (psf). We understand infiltration is being evaluated as part of the overall storm design. Our evaluation of site infiltration capacity was completed in general accordance with the requirements of the City of Renton’s 2022 Stormwater Design Manual (2022 SWDM), which locally modifies the 2021 King County Surface Water Design Manual (2021 KCSWDM). Discussion on infiltration feasibility can be found in the Infiltration Feasibility section of this letter. DR A F T Park AVE 5, LLC ES-9475 November 27, 2023 Page 2 Earth Solutions NW, LLC Surface Conditions The subject site is located at 3108 Park Avenue North in Renton, Washington. The approximate location of the site is illustrated on the attached Vicinity Map (Plate 1). The property is comprised of one tax parcel (King County Parcel No. 3342103216), totaling about 0.59 acres. The site is currently developed with a single-family residence and associated improvements. Vegetation surrounding the structures consists of grass landscaping areas and scattered trees. The site topography gently descends from east to west, with about 15 feet of elevation change across the property. Subsurface Conditions An ESNW representative observed, logged, and sampled four test pits, excavated at accessible locations within the property boundaries, on October 11, 2023, using a mini-trackhoe and operator retained by ESNW. The approximate locations of the test pits are depicted on Plate 2 (Test Pit Location Plan). Please refer to the attached test pit logs for a more detailed description of subsurface conditions. Representative soil samples collected at the test pit locations were evaluated in general accordance with Unified Soil Classification System (USCS) and United States Department of Agriculture (USDA) methods and procedures. Topsoil Topsoil was observed extending to depths of approximately 12 to 18 inches below the existing ground surface (bgs). The topsoil was characterized by dark brown color and fine organic material. Native Soil Underlying topsoil, native soil was encountered as loose to dense poorly graded sand with silt, silty sand, and sandy silt (USCS: SP-SM, SM, and ML, respectively). Native soil relative density generally increased with depth. Native soil was generally encountered in a moist to wet condition. Geologic Setting The referenced geologic map identifies Vashon recessional outwash deposits (Qvr) across the subject property and surrounding area. As described on the geologic map resource, recessional outwash deposits consist primarily of moderately sorted to well-sorted, stratified gravel and sand. Recessional outwash deposits were deposited by meltwater flowing from the receding Vashon glacier. The referenced Web Soil Survey (WSS) identifies Indianola loamy sand (Map Unit: InC) as the primary soil unit underlying the subject site. The Indianola series was formed in terraces, kames, and eskers and is derived from sandy glacial outwash. Based on our field observations, native soil likely to be exposed during grading activities will be generally consistent with recessional outwash deposits overlying glacial till deposits and Indianola series soil. DR A F T Park AVE 5, LLC ES-9475 November 27, 2023 Page 3 Earth Solutions NW, LLC Groundwater Groundwater seepage was not encountered during July 2023 subsurface exploration. However, iron oxide staining was observed at depths of about two and one-half to five feet bgs which is indicative of seasonal groundwater seepage. Glacial deposits commonly exhibit seasonal, perched seepage zones. Groundwater seepage rates and elevations fluctuate depending on many factors, including precipitation duration and intensity, the time of year, and soil conditions. In general, groundwater flow rates are higher during the winter, spring, and early summer months. Geologically Hazardous Areas As part of this assessment, ESNW reviewed Chapter 4.3.050 of the Renton Municipal Code (RMC) and County-maintained online mapping to evaluate the site for the presence of geologically hazardous areas, as defined by the City. Based on review of the referenced RMC and City maps, the subject site is not mapped within, or adjacent to, any geologic hazard areas. Based on our fieldwork performed at the subject site, it is our opinion the site does not contain geologically hazardous areas. Structural Fill Structural fill is defined as compacted soil placed in foundation, slab-on-grade, roadway, permanent slope, retaining wall, and utility trench backfill areas. Structural fill placed and compacted during site grading activities should meet the following specifications and guidelines: Structural fill material Granular soils* Moisture content At or slightly above optimum** Relative compaction (minimum) 95 percent (Modified Proctor) Loose lift thickness (maximum) 12 inches * The existing soil may not be suitable for use as structural fill unless the soil is at (or slightly above) the optimum moisture content at the time of placement and compaction. ** Soil shall not be placed dry of optimum and should be evaluated by ESNW during construction. Temporary Excavations Based on the soil conditions observed at the test pit locations, the following allowable temporary slope inclinations, as a function of horizontal to vertical (H:V) inclination, may be used. The applicable Federal Occupation Safety and Health Administration and Washington Industrial Safety and Health Act soil classifications are also provided: Areas exposing groundwater seepage 1.5H:1V (Type C) Loose soil 1.5H:1V (Type C) Medium dense soil 1H:1V (Type B) Dense to very dense, cemented native soil 0.75H:1V (Type A) DR A F T Park AVE 5, LLC ES-9475 November 27, 2023 Page 4 Earth Solutions NW, LLC The presence of perched groundwater may cause localized sloughing of temporary slopes. An ESNW representative should observe temporary and permanent slopes to confirm the slope inclinations are suitable for the exposed soil conditions and to provide additional excavation and slope recommendations, as necessary. If the recommended temporary slope inclinations cannot be achieved, temporary shoring may be necessary to support excavations. Permanent slopes should be planted with vegetation to enhance stability and to minimize erosion and should maintain a gradient of 2H:1V or flatter. Foundations The proposed residential structures can be constructed upon a conventional continuous and spread footing foundation system bearing on competent native soil or new structural fill placed directly on competent native soil. Competent native soil suitable for support of foundations will likely be encountered beginning at depths of about two to three feet bgs. We recommend compacting the recessional outwash sand soil in-place where it is encountered in foundation subgrade areas. ESNW should be retained during construction to perform a foundation subgrade evaluation prior to formwork. Where loose or unsuitable conditions are encountered at foundation subgrade elevations, compaction of the soils to the specifications of structural fill or overexcavation and replacement with structural fill will be necessary. Provided the structures are supported as recommended, the following parameters may be used for foundation design: Allowable soil bearing capacity 2,500 psf Passive earth pressure 300 pcf Coefficient of friction 0.40 The passive earth pressure value provided above assumes the foundation will be backfilled with structural fill. A factor-of-safety of 1.5 has been applied to the passive earth pressure and coefficient of friction values provided in this section. For short-term wind and seismic loading, a one-third increase in the allowable soil bearing capacity may be assumed. With structural loading as expected, total settlement in the range of one inch is anticipated, with differential settlement of about one-half inch. Most of the anticipated settlement should occur during construction as dead loads are applied. Slab-on-Grade Floors Slab-on-grade floors for the proposed structures should be supported on a well-compacted, firm, and unyielding subgrade. Where feasible, native soils exposed at the slab-on-grade subgrade level can likely be compacted in situ to the specifications described in this section. Unstable or yielding areas of subgrade should be recompacted, or overexcavated and replaced with suitable structural fill, prior to slab construction. DR A F T Park AVE 5, LLC ES-9475 November 27, 2023 Page 5 Earth Solutions NW, LLC A capillary break consisting of a minimum of four inches of free-draining crushed rock or gravel should be placed below the slab. The free-draining material should have a fines content of 5 percent or less (where the fines content is defined as the percent passing the Number 200 sieve, based on the minus three-quarter-inch fraction). In areas where slab moisture is undesirable, installation of a vapor barrier below the slab should be considered. If a vapor barrier is utilized, it should be a material specifically designed for use as a vapor barrier and should be installed in accordance with manufacturer specifications. Retaining Walls Retaining walls must be designed to resist earth pressures and applicable surcharge loads. The following parameters may be used for design: Active earth pressure (unrestrained condition) 35 pcf (equivalent fluid) At-rest earth pressure (restrained condition) 55 pcf Traffic surcharge* (passenger vehicles) 70 psf (rectangular distribution) Passive earth pressure 300 pcf (equivalent fluid) Coefficient of friction 0.40 Seismic surcharge 8H psf** * Where applicable. ** Where H equals the retained height (in feet). The passive earth pressure and coefficient of friction values include a safety factor of 1.5. The above design parameters are based on a level backfill condition and level grade at the wall toe. Revised design values will be necessary if sloping grades are to be used above or below retaining walls. Additional surcharge loading from adjacent foundations, sloped backfill, or other relevant loads should be included in the retaining wall design. Retaining walls should be backfilled with free-draining material that extends along the height of the wall and a distance of at least 18 inches behind the wall. In lieu of 18 inches of a free-draining material, a drainage mat can be considered. ESNW should evaluate the suitability of drainage mat application during construction. The upper 12 inches of the wall backfill may consist of a less permeable soil, if desired. A perforated drainpipe should be placed along the base of the wall and connected to an approved discharge location. A typical retaining wall drainage detail is provided on Plate 3. If drainage is not provided, hydrostatic pressures should be included in the wall design. DR A F T Park AVE 5, LLC ES-9475 November 27, 2023 Page 6 Earth Solutions NW, LLC Seismic Design The 2018 International Building Code (2018 IBC) recognizes the most recent edition of the Minimum Design Loads for Buildings and Other Structures manual (ASCE 7-16) for seismic design, specifically with respect to earthquake loads. Based on the soil conditions encountered at the test locations, the parameters and values provided below are recommended for seismic design per the 2018 IBC. Parameter Value Site Class D* Mapped short period spectral response acceleration, SS (g) 1.445 Mapped 1-second period spectral response acceleration, S1 (g) 0.497 Short period site coefficient, Fa 1.0 Long period site coefficient, Fv 1.803** Adjusted short period spectral response acceleration, SMS (g) 1.445 Adjusted 1-second period spectral response acceleration, SM1 (g) 0.896** Design short period spectral response acceleration, SDS (g) 0.963 Design 1-second period spectral response acceleration, SD1 (g) 0.597** * Assumes medium dense to dense soil conditions (at depth), encountered to a maximum depth of 10 feet bgs during the October 2023 field exploration, remain medium dense to dense to at least 100 feet bgs. ** Values assume Fv may be determined using linear interpolation per Table 11.4-2 in ASCE 7-16. Liquefaction Liquefaction is a phenomenon that can occur within a soil profile as a result of an intense ground shaking or loading condition. Most commonly, liquefaction is caused by ground shaking during an earthquake. Sand or silt soil that is loose, cohesionless, and below the groundwater table are most susceptible to liquefaction. During the ground shaking, the soil contracts, and porewater pressure increases. The increased porewater pressure occurs quickly and without sufficient time to dissipate, resulting in water flowing upward to the ground surface and a liquefied soil condition. Soil in a liquefied condition possesses very little shear strength in comparison to the drained condition, which can result in a loss of foundation support for structures. The referenced liquefaction susceptibility map indicates the subject site maintains low to moderate liquefaction susceptibility. In our opinion, site susceptibility to liquefaction may be considered low. The relative density of the native soil and absence of an established shallow groundwater table are the primary bases for this opinion. DR A F T Park AVE 5, LLC ES-9475 November 27, 2023 Page 7 Earth Solutions NW, LLC Drainage Zones of perched groundwater seepage should be anticipated in site excavations depending on the time of year grading operations take place. Temporary measures to control surface water runoff and groundwater during construction would likely involve passive elements such as interceptor trenches and sumps. ESNW should be consulted during preliminary grading to identify areas of seepage and to provide recommendations to reduce the potential for instability related to seepage effects. Finish grades must be designed to direct surface drain water away from the structures. Water must not be allowed to pond adjacent to the structure. Grades adjacent to the building should be sloped away from the building at a gradient of either at least 2 percent for a horizontal distance of 10 feet or the maximum allowed by adjacent structures. In our opinion, footing drains should be installed along building perimeter footings. A typical footing drain detail is provided on Plate 4. Infiltration Feasibility As indicated in the Subsurface Conditions section of this letter, native soils encountered during the fieldwork were characterized primarily as recessional outwash sand deposits underlain by glacial till deposits. In our opinion, infiltration is feasible in areas where adequate separation from impermeable layers can be established or in areas where cleaner sand deposits are exposed underlying impermeable layers. For preliminary design purposes, we recommend a preliminary long-term design rate of one inch per hour. Use of this rate requires the infiltration facilities to be sited within relatively clean sand deposits. Adequate separation between the infiltration facility bottom and seasonal high groundwater levels or impermeable layers must be established. In-situ infiltration testing will be required by the City to confirm infiltration rates. ESNW can provide further evaluation and recommendations for site BMPs as plans develop. ESNW should review final stormwater management plans to provide supplementary recommendations, as needed. Additionally, ESNW should observe infiltration system excavations and construction to confirm suitable soil conditions if infiltration is pursued. Limitations & Additional Services This geotechnical evaluation report has been prepared for the exclusive use of Park AVE 5, LLC and its representatives. The recommendations and conclusions provided in this letter are professional opinions consistent with the level of care and skill that is typical of other members in the profession currently practicing under similar conditions in this area. A warranty is not expressed or implied. Variations in the soil and groundwater conditions observed at the test sites may exist and may not become evident until construction. ESNW should reevaluate the conclusions in this letter if variations are encountered. DR A F T Park AVE 5, LLC ES-9475 November 27, 2023 Page 8 Earth Solutions NW, LLC ESNW should have an opportunity to review the final design with respect to the geotechnical recommendations provided in this letter. ESNW should also be retained to provide testing and consultation services during the earthwork phase of construction. We trust this letter meets your current needs. Should you have any questions regarding the content herein, or require additional information, please call. Sincerely, EARTH SOLUTIONS NW, LLC Kyler T. Kelly, L.G. Henry T. Wright, P.E. Project Geologist Associate Principal Engineer Attachments: Plate 1 – Vicinity Map Plate 2 – Test Pit Location Plan Plate 3 – Retaining Wall Drainage Detail Plate 4 – Footing Drain Detail Test Pit Logs Grain Size Distribution References: RMC 2022 SWDM 2021 KCSWDM Liquefaction Susceptibility for King County (Map 11-5), incorporating data from the Washington State Department of Natural Resources, dated May 2010 Geologic Map of King County, Washington, compiled by D.B. Booth et al., dated March 2007 WSS, maintained by the Natural Resources Conservation Service under the USDA DR A F T Drawn CAM Checked KTK Date Nov. 2023 Date 11/03/2023 Proj. No. 9475 Plate 1 Geotechnical Engineering,Construction Observation/Testing and Environmental Services Earth Solutions NWLLCEarthSolutionsNWLLC EarthSolutions NW LLC Vicinity Map 3108 Park Avenue N. Renton, Washington Reference: King County, Washington OpenStreetMap.org NORTH NOTE: This plate may contain areas of color. ESNW cannot be responsible for any subsequent misinterpretation of the information resulting from black & white reproductions of this plate. Renton SITE Newcastle Lake Washington DR A F T Drawn CAM Checked KTK Date Nov. 2023 Date 11/03/2023 Proj. No. 9475 Plate 2 Geotechnical Engineering,Construction Observation/Testing and Environmental Services Earth Solutions NWLLCEarthSolutionsNWLLC EarthSolutions NW LLC TP-1 TP-2 TP-3 TP-4 pa r k a v e n u e n . ga r d e n a v e n u e n . Test Pit Location Plan 3108 Park Avenue N. Renton, Washington NOTE: This plate may contain areas of color. ESNW cannot be responsible for any subsequent misinterpretation of the information resulting from black & white reproductions of this plate. NOTE: The graphics shown on this plate are not intended for design purposes or precise scale measurements, but only to illustrate the approximate test locations relative to the approximate locations of existing and / or proposed site features. The information illustrated is largely based on data provided by the client at the time of our study. ESNW cannot be responsible for subsequent design changes or interpretation of the data by others. LEGEND Approximate Location of ESNW Test Pit, Proj. No. ES-9475, Oct. 2023 Subject Site Existing Building TP-1 NOT - TO - SCALE NORTH DR A F T Geotechnical Engineering,Construction Observation/Testing and Environmental Services Drawn CAM Checked KTK Date Nov. 2023 Date 11/03/2023 Proj. No. 9475 Plate 3 Earth Solutions NWLLCEarthSolutionsNWLLC EarthSolutions NW LLC NOTES: Free-draining Backfill should consist of soil having less than 5 percent fines. Percent passing No. 4 sieve should be 25 to 75 percent. Sheet Drain may be feasible in lieu of Free-draining Backfill, per ESNW recommendations. Drain Pipe should consist of perforated, rigid PVC Pipe surrounded with 1-inch Drain Rock. LEGEND: Free-draining Structural Backfill 1-inch Drain Rock 18" Min. Structural Fill Perforated Rigid Drain Pipe (Surround in Drain Rock) SCHEMATIC ONLY - NOT TO SCALE NOT A CONSTRUCTION DRAWING Retaining Wall Drainage Detail 3108 Park Avenue N. Renton, Washington DR A F T Geotechnical Engineering,Construction Observation/Testing and Environmental Services Drawn CAM Checked KTK Date Nov. 2023 Date 11/03/2023 Proj. No. 9475 Plate 4 Earth Solutions NWLLCEarthSolutionsNWLLC EarthSolutions NW LLC Slope Perforated Rigid Drain Pipe (Surround in Drain Rock) 18" Min. NOTES: Do NOT tie roof downspouts to Footing Drain. Surface Seal to consist of 12" of less permeable, suitable soil. Slope away from building. LEGEND: Surface Seal: native soil or other low-permeability material. 1-inch Drain Rock SCHEMATIC ONLY - NOT TO SCALE NOT A CONSTRUCTION DRAWING Footing Drain Detail 3108 Park Avenue N. Renton, Washington DR A F T > 1 2 % F i n e s < 5 % F i n e s Hi g h l y Or g a n i c So i l s Si l t s a n d C l a y s Li q u i d L i m i t 5 0 o r M o r e Si l t s a n d C l a y s Li q u i d L i m i t L e s s T h a n 5 0 Fi n e - G r a i n e d S o i l s - 50 % o r M o r e P a s s e s N o . 2 0 0 S i e v e Co a r s e - G r a i n e d S o i l s - Mo r e T h a n 5 0 % R e t a i n e d o n N o . 2 0 0 S i e v e Sa n d s - 5 0 % o r M o r e o f C o a r s e Fr a c t i o n P a s s e s N o . 4 S i e v e Gr a v e l s - M o r e T h a n 5 0 % o f C o a r s e Fr a c t i o n R e t a i n e d o n N o . 4 S i e v e > 1 2 % F i n e s < 5 % F i n e s GW GP GM GC SW SP SM SC ML CL OL MH CH OH PT Well-graded gravel with or without sand, little to no fines Poorly graded gravel with or without sand, little to no fines Silty gravel with or without sand Clayey gravel with or without sand Well-graded sand with or without gravel, little to no fines Poorly graded sand with or without gravel, little to no fines Silty sand with or without gravel Clayey sand with or without gravel Silt with or without sand or gravel; sandy or gravelly silt Clay of low to medium plasticity; lean clay with or without sand or gravel; sandy or gravelly lean clay Organic clay or silt of low plasticity Elastic silt with or without sand or gravel; sandy or gravelly elastic silt Clay of high plasticity; fat clay with or without sand or gravel; sandy or gravelly fat clay Organic clay or silt of medium to high plasticity Peat, muck, and other highly organic soils EEaarrtthh SSoolluuttiioonnss NNWW LLC Geotechnical Engineering,Construction Observation/Testing and Environmental Services EXPLORATION LOG KEY Fi l l FILL Made Ground Classifications of soils in this geotechnical report and as shown on the exploration logs are based on visual field and/or laboratory observations, which include density/consistency, moisture condition, grain size, and plasticity estimates, and should not be construed to imply field or laboratory testing unless presented herein. Visual-manual and/or laboratory classification methods of ASTM D2487 and D2488 were used as an identification guide for the Unified Soil Classification System. Terms Describing Relative Density and Consistency Coarse-Grained Soils: Fine-Grained Soils: SPT blows/foot SPT blows/foot Test Symbols & Units Fines = Fines Content (%) MC = Moisture Content (%) DD = Dry Density (pcf) Str = Shear Strength (tsf) PID = Photoionization Detector (ppm) OC = Organic Content (%) CEC = Cation Exchange Capacity (meq/100 g) LL = Liquid Limit (%) PL = Plastic Limit (%) PI = Plasticity Index (%) Component Definitions Descriptive Term Size Range and Sieve Number Smaller than No. 200 (0.075 mm) Boulders Modifier Definitions Percentage by Weight (Approx.) < 5 5 to 14 15 to 29 > 30 _ Modifier Trace (sand, silt, clay, gravel) Slightly (sandy, silty, clayey, gravelly) Sandy, silty, clayey, gravelly Very (sandy, silty, clayey, gravelly) Moisture Content Dry - Absence of moisture, dusty, dry to the touch Damp - Perceptible moisture, likely below optimum MC Moist - Damp but no visible water, likely at/near optimum MC Wet - Water visible but not free draining, likely above optimum MC Saturated/Water Bearing - Visible free water, typically below groundwater table Symbols Cement grout surface seal Bentonite chips Grout seal Filter pack with blank casing section Screened casing or Hydrotip with filter pack End cap ATD = At time of drilling Static water level (date) _> 50 Density Very Loose Loose Medium Dense Dense Very Dense Consistency Very Soft Soft Medium Stiff Stiff Very Stiff Hard < 4 4 to 9 10 to 29 30 to 49 < 2 2 to 3 4 to 7 8 to 14 15 to 29 _> 30 LLC EarthSolutions NW LLC Cobbles Gravel Coarse Gravel Fine Gravel Sand Coarse Sand Medium Sand Fine Sand Silt and Clay Larger than 12" 3" to 12" 3" to No. 4 (4.75 mm) 3" to 3/4" 3/4" to No. 4 (4.75 mm) No. 4 (4.75 mm) to No. 200 (0.075 mm) No. 4 (4.75 mm) to No. 10 (2.00 mm) No. 10 (2.00 mm) to No. 40 (0.425 mm) No. 40 (0.425 mm) to No. 200 (0.075 mm)DR A F T GB GB GB MC = 13.6 Fines = 29.5 MC = 9.9 MC = 20.7 TPSL SM SM Dark brown TOPSOIL Dark brown silty SAND, loose, moist Brown silty SAND, medium dense, moist [USDA Classification: slightly gravelly fine sandy LOAM] -probed 8" -light iron oxide staining to 5', roots -becomes gray, dense, weakly cemented -probed 2" -boulder -becomes wet Test pit terminated at 9.0 feet below existing grade. No groundwater encountered during excavation. No caving observed. LIMITATIONS: Ground elevation (if listed) is approximate; the test location was not surveyed. Coordinates are approximate and based on the WGS84 datum. Do not rely on this test log as a standalone document. Refer to the text of the geotechnical report for a complete understanding of subsurface conditions. 1.5 2.0 9.0 SA M P L E T Y P E NU M B E R DE P T H (f t ) 0.0 2.5 5.0 7.5 PAGE 1 OF 1 TEST PIT NUMBER TP-1 CHECKED BY HTW NOTES SURFACE CONDITIONS Grass AT TIME OF EXCAVATIONAT TIME OF EXCAVATION AFTER EXCAVATION EXCAVATION CONTRACTOR NW Excavating DATE STARTED 10/11/23 COMPLETED 10/11/23 GROUND WATER LEVEL: GROUND ELEVATION LOGGED BY KTK LATITUDE 47.51985 LONGITUDE -122.20084 PROJECT NUMBER ES-9475 PROJECT NAME 3108 Park Avenue N. GE N E R A L B H / T P / W E L L - 9 4 7 5 . G P J - G I N T U S . G D T - 1 1 / 2 7 / 2 3 Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 TESTS U. S . C . S . MATERIAL DESCRIPTION GR A P H I C LO G DR A F T GB GB GB GB MC = 7.3 MC = 7.4 Fines = 9.3 MC = 20.6 MC = 26.2 TPSL SP- SM ML Dark brown TOPSOIL Brown poorly graded SAND with silt, medium dense, moist -probed 8" -light iron oxide staining to 5' [USDA Classification: slightly gravelly SAND] Gray sandy SILT, dense, moist to wet -weakly cemented Test pit terminated at 10.0 feet below existing grade. No groundwater encountered during excavation. No caving observed. LIMITATIONS: Ground elevation (if listed) is approximate; the test location was not surveyed. Coordinates are approximate and based on the WGS84 datum. Do not rely on this test log as a standalone document. Refer to the text of the geotechnical report for a complete understanding of subsurface conditions. 1.5 5.0 10.0 SA M P L E T Y P E NU M B E R DE P T H (f t ) 0.0 2.5 5.0 7.5 10.0 PAGE 1 OF 1 TEST PIT NUMBER TP-2 CHECKED BY HTW NOTES SURFACE CONDITIONS Grass AT TIME OF EXCAVATIONAT TIME OF EXCAVATION AFTER EXCAVATION EXCAVATION CONTRACTOR NW Excavating DATE STARTED 10/11/23 COMPLETED 10/11/23 GROUND WATER LEVEL: GROUND ELEVATION LOGGED BY KTK LATITUDE 47.51969 LONGITUDE -122.20074 PROJECT NUMBER ES-9475 PROJECT NAME 3108 Park Avenue N. GE N E R A L B H / T P / W E L L - 9 4 7 5 . G P J - G I N T U S . G D T - 1 1 / 2 7 / 2 3 Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 TESTS U. S . C . S . MATERIAL DESCRIPTION GR A P H I C LO G DR A F T GB GB GB GB MC = 12.9 MC = 14.5 Fines = 52.9 MC = 10.2 MC = 8.4 Fines = 13.2 TPSL SM ML SM Dark brown TOPSOIL Brown silty SAND, loose, moist -light iron oxide staining to 4.5', probed 8" Gray sandy SILT, medium dense, moist -becomes dense, weakly cemented [USDA Classification: slightly gravelly LOAM] -probed 3" -boulder Gray silty SAND, medium dense to dense, moist [USDA Classification: slightly gravelly SAND] Test pit terminated at 10.0 feet below existing grade. No groundwater encountered during excavation. No caving observed. LIMITATIONS: Ground elevation (if listed) is approximate; the test location was not surveyed. Coordinates are approximate and based on the WGS84 datum. Do not rely on this test log as a standalone document. Refer to the text of the geotechnical report for a complete understanding of subsurface conditions. 1.5 3.0 7.5 10.0 SA M P L E T Y P E NU M B E R DE P T H (f t ) 0.0 2.5 5.0 7.5 10.0 PAGE 1 OF 1 TEST PIT NUMBER TP-3 CHECKED BY HTW NOTES SURFACE CONDITIONS Grass AT TIME OF EXCAVATIONAT TIME OF EXCAVATION AFTER EXCAVATION EXCAVATION CONTRACTOR NW Excavating DATE STARTED 10/11/23 COMPLETED 10/11/23 GROUND WATER LEVEL: GROUND ELEVATION LOGGED BY KTK LATITUDE 47.51972 LONGITUDE -122.20138 PROJECT NUMBER ES-9475 PROJECT NAME 3108 Park Avenue N. GE N E R A L B H / T P / W E L L - 9 4 7 5 . G P J - G I N T U S . G D T - 1 1 / 2 7 / 2 3 Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 TESTS U. S . C . S . MATERIAL DESCRIPTION GR A P H I C LO G DR A F T GB GB GB MC = 9.4 MC = 17.3 MC = 13.4 Fines = 32.9 TPSL SP- SM SM Dark brown TOPSOIL Brown poorly graded SAND with silt, medium dense, moist -probed 6" -becomes dense, weakly cemented, light iron oxide staining to 5' Gray silty SAND, dense, moist to wet -weakly cemented -reduced fines content to BOH [USDA Classification: slightly gravelly sandy LOAM] Test pit terminated at 10.0 feet below existing grade. No groundwater encountered during excavation. No caving observed. LIMITATIONS: Ground elevation (if listed) is approximate; the test location was not surveyed. Coordinates are approximate and based on the WGS84 datum. Do not rely on this test log as a standalone document. Refer to the text of the geotechnical report for a complete understanding of subsurface conditions. 1.0 5.0 10.0 SA M P L E T Y P E NU M B E R DE P T H (f t ) 0.0 2.5 5.0 7.5 10.0 PAGE 1 OF 1 TEST PIT NUMBER TP-4 CHECKED BY HTW NOTES SURFACE CONDITIONS Grass AT TIME OF EXCAVATIONAT TIME OF EXCAVATION AFTER EXCAVATION EXCAVATION CONTRACTOR NW Excavating DATE STARTED 10/11/23 COMPLETED 10/11/23 GROUND WATER LEVEL: GROUND ELEVATION LOGGED BY KTK LATITUDE 47.51985 LONGITUDE -122.20162 PROJECT NUMBER ES-9475 PROJECT NAME 3108 Park Avenue N. GE N E R A L B H / T P / W E L L - 9 4 7 5 . G P J - G I N T U S . G D T - 1 1 / 2 7 / 2 3 Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 TESTS U. S . C . S . MATERIAL DESCRIPTION GR A P H I C LO G DR A F T 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 0.0010.010.1110100 2.74 LL TP-01 TP-02 TP-03 TP-03 TP-04 0.077 3/4 U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS GRAVEL SAND 9.5 4.75 37.5 4.75 4.75 %Silt 1.46 TP-01 TP-02 TP-03 TP-03 TP-04 2 2003 Cc CuClassification %Clay 16 PID60 D30 coarse SILT OR CLAYfinemedium GRAIN SIZE IN MILLIMETERS 3/8 50 2.0ft. 3.0ft. 4.0ft. 10.0ft. 10.0ft. 2.00ft. 3.00ft. 4.00ft. 10.00ft. 10.00ft. PL 3 D100 140 Specimen Identification 1 fine 6 HYDROMETER 304 29.5 9.3 52.9 13.2 32.9 101/2 COBBLES Specimen Identification 4 coarse 20 401.5 8 14 USDA: Brown Slightly Gravelly Fine Sandy Loam. USCS: SM. USDA: Brown Slightly Gravelly Sand. USCS: SP-SM. USDA: Gray Slightly Gravelly Loam. USCS: Sandy ML. USDA: Gray Slightly Gravelly Sand. USCS: SM. USDA: Gray Slightly Gravelly Sandy Loam.USCS: SM. 6 60 PE R C E N T F I N E R B Y W E I G H T D10 0.077 0.155 0.167 0.2 0.212 0.105 0.313 0.25 GRAIN SIZE DISTRIBUTION 100 PROJECT NUMBER ES-9475 PROJECT NAME 3108 Park Avenue N GR A I N S I Z E U S D A E S - 9 4 7 5 3 1 0 8 P A R K A V E N U E N . G P J G I N T U S L A B . G D T 1 0 / 2 7 / 2 3 Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 DR A F T Soil Map—King County Area, Washington (Jones Renton Short Plat - North Phase) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 5/8/2024 Page 1 of 3 52 6 3 2 1 0 52 6 3 2 2 0 52 6 3 2 3 0 52 6 3 2 4 0 52 6 3 2 5 0 52 6 3 2 6 0 52 6 3 2 1 0 52 6 3 2 2 0 52 6 3 2 3 0 52 6 3 2 4 0 52 6 3 2 5 0 52 6 3 2 6 0 560090 560100 560110 560120 560130 560140 560150 560160 560170 560180 560090 560100 560110 560120 560130 560140 560150 560160 560170 560180 47° 31' 12'' N 12 2 ° 1 2 ' 6 ' ' W 47° 31' 12'' N 12 2 ° 1 2 ' 2 ' ' W 47° 31' 10'' N 12 2 ° 1 2 ' 6 ' ' W 47° 31' 10'' N 12 2 ° 1 2 ' 2 ' ' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 10N WGS84 0 20 40 80 120 Feet 0 5 10 20 30 Meters Map Scale: 1:451 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: King County Area, Washington Survey Area Data: Version 19, Aug 29, 2023 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jul 31, 2022—Aug 8, 2022 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Soil Map—King County Area, Washington (Jones Renton Short Plat - North Phase) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 5/8/2024 Page 2 of 3 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI InC Indianola loamy sand, 5 to 15 percent slopes 0.7 100.0% Totals for Area of Interest 0.7 100.0% Soil Map—King County Area, Washington Jones Renton Short Plat - North Phase Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 5/8/2024 Page 3 of 3 King County Area, Washington InC—Indianola loamy sand, 5 to 15 percent slopes Map Unit Setting National map unit symbol: 2t635 Elevation: 0 to 980 feet Mean annual precipitation: 30 to 81 inches Mean annual air temperature: 48 to 50 degrees F Frost-free period: 170 to 210 days Farmland classification: Prime farmland if irrigated Map Unit Composition Indianola and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Indianola Setting Landform:Terraces, kames, eskers Landform position (three-dimensional):Riser Down-slope shape:Linear Across-slope shape:Linear Parent material:Sandy glacial outwash Typical profile Oi - 0 to 1 inches: slightly decomposed plant material A - 1 to 6 inches: loamy sand Bw1 - 6 to 17 inches: loamy sand Bw2 - 17 to 27 inches: sand BC - 27 to 37 inches: sand C - 37 to 60 inches: sand Properties and qualities Slope:5 to 15 percent Depth to restrictive feature:More than 80 inches Drainage class:Somewhat excessively drained Capacity of the most limiting layer to transmit water (Ksat):High to very high (5.95 to 99.90 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Available water supply, 0 to 60 inches: Low (about 3.9 inches) Interpretive groups Land capability classification (irrigated): 4e Land capability classification (nonirrigated): 4s Hydrologic Soil Group: A Ecological site: F002XA004WA - Puget Lowlands Forest Map Unit Description: Indianola loamy sand, 5 to 15 percent slopes---King County Area, Washington Jones Renton Short Plat - North Phase Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 5/8/2024 Page 1 of 2 Forage suitability group: Droughty Soils (G002XN402WA), Droughty Soils (G002XS401WA) Other vegetative classification: Droughty Soils (G002XN402WA), Droughty Soils (G002XS401WA) Hydric soil rating: No Minor Components Alderwood Percent of map unit:8 percent Landform:Hills, ridges Landform position (two-dimensional):Shoulder Landform position (three-dimensional):Nose slope, talf Down-slope shape:Convex, linear Across-slope shape:Convex Hydric soil rating: No Everett Percent of map unit:5 percent Landform:Moraines, eskers, kames Landform position (two-dimensional):Shoulder, footslope Landform position (three-dimensional):Base slope, crest Down-slope shape:Convex Across-slope shape:Convex Hydric soil rating: No Norma Percent of map unit:2 percent Landform:Drainageways, depressions Landform position (three-dimensional):Dip Down-slope shape:Linear, concave Across-slope shape:Concave Hydric soil rating: Yes Data Source Information Soil Survey Area: King County Area, Washington Survey Area Data: Version 19, Aug 29, 2023 Map Unit Description: Indianola loamy sand, 5 to 15 percent slopes---King County Area, Washington Jones Renton Short Plat - North Phase Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 5/8/2024 Page 2 of 2