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36_R_TIR_20260506_v1
May 4, 2026 Prepared for: MultiCare Health System 315 Martin Luther King Jr Way Tacoma, Washington 98405 Prepared by: Blake Lord, PE KJ Kaminanga Preliminary Technical Information Report Consulting Engineers 640 Woodland Square Loop SE, Suite 100 Lacey, WA 98503 (360) 292-7230 (360) 292-7231 FAX MultiCare Renton Off-Campus Emergency Department (OCED) CITY OF RENTON, WASHINGTON KPFF Project #: 10182600015 MultiCare Renton OCED Renton, Washington Preliminary Technical Information Report (TIR) i | P a g e PROJECT ENGINEERS CERTIFICATION: I hereby state that this Technical Information Report for MultiCare Renton OCED has been prepared by me or under my supervision and meets the standard of care and expertise, which is usual and customary in this community for professional engineers. I understand that the City of Renton does not and will not assume liability for the sufficiency, suitability, or performance of drainage facilities designed by me. P R O F ESSIONAL E N G I NEER REGIS T E R E D T OSATEOFWASHIN GT N B L A K E A . L O R D MultiCare Renton OCED Renton, Washington Preliminary Technical Information Report (TIR) ii | P a g e CONTENTS 1 Project Overview ................................................................................................................. 1 1.1 Proposal ...................................................................................................................... 1 1.2 Predeveloped Conditions ............................................................................................. 1 1.3 Developed Conditions .................................................................................................. 2 1.4 Site and Project Site Area ............................................................................................ 2 1.5 Size of Improvements .................................................................................................. 2 1.6 Disposition of Stormwater Runoff Before and After Development ................................ 3 2 Conditions and Requirements Summary ............................................................................. 3 2.1 Core Requirements ...................................................................................................... 3 2.2 Special Requirements .................................................................................................. 8 2.3 Existing Conditions ...................................................................................................... 9 2.4 Critical Areas ............................................................................................................... 9 2.5 Existing Soil Conditions ..............................................................................................10 3 Offsite Analysis ..................................................................................................................10 3.1 Task 1 - Study Area Definition and Maps ....................................................................10 3.2 Task 2 – Resource Review .........................................................................................11 3.3 Task 3 – Field Inspection ............................................................................................11 3.4 Task 4 – Drainage System Description and Problem Descriptions ..............................11 3.5 Task 5 – Mitigation of Existing or Potential Problems ..................................................11 4 Special Reports and Studies ..............................................................................................12 5 Other Permits .....................................................................................................................12 6 CSWPP Plan Analysis and Design ....................................................................................12 7 Bond Quantities, Facility Summaries, and Declaration of Covenant ...................................12 TABLES Table 1: Existing On-site and Off-site Areas ............................................................................... 2 Table 2: Proposed On-site and Off-site Areas ............................................................................ 3 APPENDICES Appendix A – TIR Worksheet Appendix B – Civil CUP Application Plan Set Appendix C – Geotechnical Engineering Services Report Appendix D – WWHM Report Appendix E – Drainage Basin Maps Appendix F – CSWPPP (Forthcoming) Appendix G – Stormwater Operations and Maintenance Manual (Forthcoming) Appendix H – Off-site Analysis Drainage System Table MultiCare Renton OCED Renton, Washington Preliminary Technical Information Report (TIR) 1 | P a g e 1 Project Overview 1.1 Proposal The MultiCare Renton Off-Campus Emergency Department (OCED) is proposed at 3116 NE Sunset Boulevard, Renton, Washington (Section 4, Township 23 North, Range 5 East) within the City limits of the City of Renton. The 3116 NE Sunset Blvd property is an existing commercial Rite Aid building on parcel #042305-9095. The property is 1.76 acres and zoned Center Village (CV). The project proposes the reuse of an existing approximately 17,000 square foot commercial building to accommodate a freestanding OCED and an outpatient medical office. The entire project proposes: • 17,556 SF (0.40 ac) of new and replaced pollution generating impervious surface (PGIS). This does not include any roof replacement proposed for the existing building. • 2,016 SF (0.05 ac) of new and replaced pervious surface. • A net reduction of impervious surfaces of approximately 2,024 SF. The 1.76-acre site has an existing stormwater drainage system composed of catch basins, storm drainage piping, and an underground concrete stormwater detention vault. The vault discharges stormwater into the existing City stormwater system in Kirkland Ave NE. The project proposes to maintain a majority of the existing storm drainage system. Minor modifications may be proposed as necessary for connection to the existing roof drainage system and any modifications required near the proposed trash enclosure. The permit submittal documents have been prepared in accordance with the 2022 City of Renton Surface Water Design Manual (SWDM). 1.2 Predeveloped Conditions The 3116 NE Sunset Boulevard property is within the Commercial Mixed Use zone within the Center Village zoning. The property is bordered by commercial and residential areas to the north, NE Sunset Boulevard/ Highway 900 to the east, NE 12th Street along the south, and Kirkland Ave NE to the west. The site topography consists of generally flat slopes, with the exception of the access points to the adjacent streets, with maximum slopes of approximately 12%. There are two sets of retaining walls adjacent to the Kirkland Ave NE right-of-way and vary from 3 to 5 feet in height. The site is currently developed with a vacant commercial Rite Aid store and associated parking. There are landscaping areas that separate the property from the public right of way, which includes vegetated lawn and trees. There are several trees along the west side of the property that will remain. The existing Rite Aid building will be renovated, while maintaining a majority of the existing building footprint. Existing stormwater runoff is collected with a series of catch basins that convey the surface runoff to the stormwater detention vault located in the southwest of the property. The roof drainage system is conveyed to the same drainage system. MultiCare Renton OCED Renton, Washington Preliminary Technical Information Report (TIR) 2 | P a g e 1.3 Developed Conditions The developed project site consists of converting the existing building into a medical use facility with associated parking lot reconfiguration, entrance, ambulance, and staff drop off/entrances, and improved ADA accessibility walkways and parking. The project proposes to utilize the existing utility service connections to the maximum extent feasible. Utility service revisions may be required and will be determined, designed, and coordinated during the preparation of construction permit documents. Analysis of the project site was performed using the 2012 Western Washington Hydrology Model (WWHM). See Appendix D for the WWHM Report. See Appendix E for the developed drainage basins associated with the project. As noted in the Pre-Application Memo and per RMC 4-8-080.D, the proposed project is considered an interior tenant improvement; therefore, frontage improvements are not required for the project. As such, drainage improvements are not proposed within the fronting right-of- ways. As described and detailed below, the project does not propose any significant storm drainage system improvements. 1.4 Site and Project Site Area The property site area is approximately 76,500 square feet (1.76 acres) with an impervious surface coverage of approximately 85.7%. The project area/disturbance limits is approximately 19,572 square feet outside the existing building. This calculation does not include the approximate 17,000 square feet building renovation. The proposed impervious surface coverage results in approximately 83.9%, a net reduction of 1.8% of the impervious surfaces. The existing and proposed surfaces are included in Appendix E, showing both the existing and proposed surfaces within the drainage basins. 1.5 Size of Improvements Table 1 summarizes existing on-site parcel areas and the off-site areas that will be disturbed with this development. Off-site areas are for the ADA ramp revision only. Table 1: Existing On-site and Off-site Areas Surface Type Site Area (sf) Offsite Area (sf) Impervious 17,476 80 Pervious 2,016 0 Total 19,492 80 Table 2 provides a summary of proposed on-site and off-site areas that will be disturbed and replaced. A majority of the replaced impervious surfaces are for vehicle, pedestrian, and ADA access improvements, and parking and circulation improvements as required per code/Preapplication Meeting comments and to ensure the site functions with the layout of the new building. MultiCare Renton OCED Renton, Washington Preliminary Technical Information Report (TIR) 3 | P a g e The grading activities associated with the development will maintain the existing grading and drainage patterns to ensure positive drainage to the existing stormwater system. All areas of proposed landscaping will be restored per the Soil Amendment BMP listed in the City of Renton SWDM. Table 2: Proposed On-site and Off-site Areas Cover Surface Type Site Area (sf) Offsite Area (sf) Total (sf) Pavement PGIS* 12,712 0 12,712 Sidewalk NPGIS** 4,764 80 4,844 Total Impervious Surface 17,476 80 17,556 Landscaping Pervious 2,016 0 2,016 Total Disturbed Area 19,492 80 19,572 *PGIS: Pollution Generating Impervious **NPGIS: Non-Pollution Generating Impervious 1.6 Disposition of Stormwater Runoff Before and After Development The existing site and roof stormwater runoff is collected in on-site catch basins and conveyed to an underground concrete detention vault located in the southwest corner of the project site. The project proposes to maintain the surface drainage patterns and the existing system. See the existing and proposed Drainage Basin Exhibits located in Appendix E and the Existing Conditions Plan in the plan set located in Appendix B. 2 Conditions and Requirements Summary The project is subject to full drainage review as determined in Table 1.1.2.A “Requirements Applied Under Each Drainage Review Type” within the City of Renton SWDM as the project proposes greater than 2,000 square feet of new plus replaced impervious surface. The project proposes approximately 17,556 square feet of new plus replaced impervious surfaces, only 399 SF being new impervious, necessary to provide a sufficient patient drop-off, staff loading area, ambulance drop-off, ADA accessible parking stalls, and an ADA accessible pathway from the building to the right-of-way (does not include replaced roof areas). Nearly all new/replaced hard surfaces are in locations of existing hard surfaces. Approximately 250 square feet of parking lot will be removed and replaced with a landscape island. 2.1 Core Requirements Core Requirement #1: Discharge at the Natural Locations As described in Section 1.3, the project will maintain the existing drainage patterns and discharge point. Core Requirement #2: Offsite Analysis An off-site analysis is located in Section 3. It has been determined that off-site and downstream drainage issues are not present and the project does not require any improvements. MultiCare Renton OCED Renton, Washington Preliminary Technical Information Report (TIR) 4 | P a g e Core Requirement #3: Flow Control The project site is located within the East Lake Washington Drainage Basin and is subject to the Peak Rate Flow Control Standard (Existing Conditions), therefore the proposed runoff peak flow rates will match, or be slightly less than, the peak flow rates of the current site conditions. The project proposes equal to or less impervious surfaces than the existing condition, therefore it is anticipated the peak flow rates of the project will meet the requirements of the Basin Control Standard. WWHM continuous runoff modeling was utilized to confirm that the proposed peak flow rates are less than those of the existing site and is included in Appendix D. A summary table of the reduction of flow rates is provided below. Return Period Existing Peak Flow Rate (cfs) Proposed Peak Flow Rate (cfs) Peak Flow Rate Reduction (cfs) Drainage Basin 1 2-year 0.25935 0.258975 0.000375 5-year 0.32765 0.327181 0.000469 10-year 0.374062 0.37353 0.000532 25-year 0.434272 0.433658 0.000614 50-year 0.48036 0.479684 0.000676 100-year 0.527571 0.526831 0.00074 Drainage Basin 2 2-year 0.332689 0.320001 0.012688 5-year 0.4212 0.4055 0.0157 10-year 0.481444 0.463735 0.017709 25-year 0.559699 0.53942 0.020279 50-year 0.619666 0.597446 0.02222 100-year 0.68115 0.656961 0.024189 Drainage Basin 3 (Bypass Basin) 2-year 0.035952 0.035952 0 5-year 0.046321 0.046321 0 10-year 0.053623 0.053623 0 25-year 0.063366 0.063366 0 50-year 0.071011 0.071011 0 100-year 0.078998 0.078998 0 Core Requirement #4: Conveyance System The existing storm drainage collection, conveyance, and detention system is not known or anticipated to have any deficiencies, appears to be in good condition, and adequately conveys runoff. History of ponding or surcharging has not been reported to the project team, therefore it can be reasonably expected the existing system is of adequate size and condition based on the current site conditions. The project proposes a net reduction of impervious surfaces and does not propose to change any of the existing drainage patterns. Flow control improvements are not required as described above, therefore the project does not propose any conveyance system improvements and the existing system will be utilized for the project. Core Requirement #5: Construction Stormwater Pollution Prevention Plan (CSWPPP) A Construction Stormwater Pollution Prevention Plan, which addresses anticipated erosion and sediment control during construction, will be completed following CUP approval and provided MultiCare Renton OCED Renton, Washington Preliminary Technical Information Report (TIR) 5 | P a g e with the construction permit document submittal. Once completed, the CSWPPP will be included in Appendix F. Core Requirement #6: Maintenance and Operations (O&M) An Operations and Maintenance Manual will be completed following CUP approval and provided with the construction permit document submittal. Once completed, the O&M Manual will be included in Appendix G. Core Requirement #7: Financial Guarantees and Liability All required financial guarantees and liability documents will be provided prior to project closeout. Core Requirement #8: Water Quality On-site stormwater runoff will be collected and conveyed to the existing on-site storm drainage system. The project proposes to utilize the “Cost Exemption for Parcel Redevelopment Projects” to be exempt from this Minimum Requirement #8 – Water Quality because the existing drainage system is currently properly functioning and the project only proposes 399 SF of NEW impervious surfaces. Responses are provided below demonstrating the project meets the “Cost Exemption for Parcel Redevelopment Projects”. Exemption Requirement a): The total valuation of the project’s proposed improvements (including interior improvements and excluding required mitigation improvements) is less than 50% of the assessed value of: (a) the existing project site improvements on commercial or industrial projects, or (b) the existing site improvements on other projects, AND Response: The total valuation of the proposed improvements is less than 50% of the assessed value of (b) the existing site improvements on other projects. Using round numbers: the project proposes approximately $12 million dollars of improvements and the existing site improvements on other sites (which we have recently constructed in other areas such as Lacey, Lynnwood, Bremerton, and others) are over $24 million dollars. Overall, when considering the cost required to build a new OCED on an undeveloped site, this project proposes less than 50% of that cost. Additional cost backup can be provided to support approval of this exemption as needed ore requested. Exemption Requirement b): Less than 5,000 square feet of new PGIS will be added, AND Response: The project proposes 399 square feet of new PGIS over the entire 1.76-acre project site and surrounding frontages. MultiCare Renton OCED Renton, Washington Preliminary Technical Information Report (TIR) 6 | P a g e Exemption Requirement c): Less than ¾ acre of new PGPS will be added. Response: The project proposes 2,016 square feet (0.05 acres) of new plus replaced pervious surfaces . If the exception cannot be obtained, the project has the ability to install water quality treatment structures to provide water quality improvements, however, this would result in significant storm drainage system revisions and require additional disturbance and hardscape replacement to a system that is currently functioning. The new water quality structures would treat the required stormwater runoff from the new and replaced pollution generating surfaces before entering the existing underground detention vault. Based on preliminary review, we anticipate these vaults to be 6’(w) x 6’(l) in size or less. Core Requirement #9: On-Site BMPs The project is subject to the Large Lot BMP requirements listed in the City’s SWDM. It has been determined that implementing any of the listed BMPs (except for soil amendment) for the project is impracticable and infeasible given: • The current site conditions and functioning drainage system. • The project is a tenant improvement with minimal site improvements to provide vehicle and pedestrian access previously mentioned. • The project proposes a reduction in net impervious surface coverage, therefore decreasing runoff and the amount of pollution generating surfaces. • Flow control and water quality facilities are not required. • Core Requirement #9: On-Site BMPs is contradictory to Core Requirement #3: Flow Control and Core Requirement #8: Water Quality: o #3: Flow Control: The project is subject to Peak Rate Flow Control Standard (Existing Conditions), therefore the proposed runoff peak flow rates are required to match, or be slightly less, than the peak flow rates of the current site conditions to ensure the project does not cause downstream flooding problems. Implementing flow control BMPs as part of Core Requirement #9 would require more stringent flow control standards than is allowable in the East Lake Washington Drainage Basin. o #8: Water Quality: The project proposes to utilize the “Cost Exemption for Parcel Redevelopment Projects”, therefore if approved, the project does not require water quality treatment for the new pollution generating surfaces. Implementing water quality BMPs as part of Core Requirement #9 would require more stringent water quality standards than is required. Using the City’s SWDM as a template, the following BMPs in the order they are listed in the drainage manual are summarized below. The first BMP for each surface area type to be deemed feasible shall be used: Section 1.2.9.2.2 Large Lot BMP Requirements Section 1. Full dispersion of targeted surfaces MultiCare Renton OCED Renton, Washington Preliminary Technical Information Report (TIR) 7 | P a g e Infeasible as the area and vegetation required for full dispersion are not present on-site. Section 2. Full Infiltration of roof runoff of targeted surfaces Runoff from the existing building is currently being conveyed to the existing storm drainage system which was sized and designed to manage the runoff. Installation of a new infiltration system on the already developed site, which would require unnecessary replacement of hard surfaces that would otherwise be preserved, is impracticable and therefore infeasible. Section 3. Full infiltration, limited infiltration, and Bioretention Runoff from the existing site is currently being conveyed to the existing storm drainage system which was sized and designed to manage the runoff. These facilities would be difficult to locate on the already functional site. Installation of new infiltration systems or bioretention swales on the already developed site, which would require unnecessary replacement of hard surfaces that would otherwise be preserved, is impracticable and therefore infeasible. Section 3. Permeable Pavement Permeable pavement is impracticable and infeasible given the existing site conditions and that at some areas on the site, the cation exchange capacity of the soils does not meet the required 5 MEQ/100G, as identified in Section 3.7.3 of the Geotechnical Engineering Services Report included in Appendix C. Furthermore, the use of permeable pavement would induce unnecessary construction and future maintenance cost responsibilities to the homeowner. In addition, permeable pavements are prone to failures, especially when not routinely maintained. Section 4. Basic Dispersion Infeasible as the area required for basic dispersion is not present on-site. Section 5. BMP implementation percentages BMPs cannot reasonably and feasibly be implemented as described above. Section 6. Moisture Holding capacity of new pervious surfaces The Soil Amendment BMP will be implemented at all locations of new or replaced pervious surfaces. Section 7. Perforated pipe connections of roof downspouts Runoff from the existing building is currently being conveyed to the existing storm drainage system which was sized and designed to manage the runoff. Installation of a new perforated pipe connection from the building to the infiltration system on this already developed site, which would require unnecessary replacement of hard surfaces that would otherwise be preserved, is impracticable and therefore infeasible. MultiCare Renton OCED Renton, Washington Preliminary Technical Information Report (TIR) 8 | P a g e Additionally, if the project opted to address Core Requirement #9 by choosing to meet the LID performance standard identified in section 1.2.9.1 B in the City’s SWDM, the project is still required to meet the area-specific flow control requirements as determined in Core Requirement #3. As demonstrated above, the project as proposed meets the Rate Flow Control Standard (Existing Conditions) of the East Lake Washington Drainage Basin by maintaining the existing storm drainage system. Therefore, it is determined and justified that Core Requirement #9 is addressed without the need for any significant drainage system modifications. 2.2 Special Requirements Special Requirement #1: Other Adopted Area-Specific Requirements The project site is located within the East Lake Washington Drainage Basin and is subject to the Peak Rate Flow Control Standard (Existing Conditions), therefore the proposed runoff peak flow rates will match, or be slightly less than, the peak flow rates of the current site conditions. The project proposes equal to or less impervious surfaces than the existing condition, therefore it is anticipated the peak flow rates of the project will meet the requirement of Basin Control Standard. Special Requirement #2: Flood Hazard Area Delineation Based on review of the City and King County’s GIS mapping, the project site is not known to be within a flood hazard area. Special Requirement #3: Flood Protection Facilities Based on review of the City and King County’s GIS mapping, the project site is not within the protection limits of any flood protection facilities, nor are any proposed. Special Requirement #4: Source Control The following source controls may be implemented as required: Structural Source Controls • Fuel Storage Containment: The proposed emergency generator will include an above- ground double-walled diesel fuel tank. A Hazardous Materials Management Statement is provided with the CUP submittal describing how materials will be stored and handled • Trash and Waste Area Roofing: The outdoor dumpster/solid waste enclosure will be roofed or enclosed to prevent rainwater from leaching pollutants. Secondary Containment: • Medical Gas Systems: Separate plans and permits will be provided and obtained for compressed gas systems. Operational Source Controls (Post-Occupancy) • Spill Prevention and Cleanup: A spill kit must be maintained on-site near the generator and fuel storage areas. This includes having procedures for immediate cleanup of drips or leaks from ambulances and delivery vehicles. • Chemical and Fertilizer Management: The project will follow the Landscape Management Plan and implement standard BMPs to minimize the use of pesticides and MultiCare Renton OCED Renton, Washington Preliminary Technical Information Report (TIR) 9 | P a g e fertilizers and avoid their transport into the storm system • Vehicle Maintenance Restrictions: On-site vehicle maintenance is not anticipated to occur on-site. Construction-Phase Source Controls • During the construction of the building improvement and parking lot reconfiguration, the following must be implemented via the Stormwater Pollution Prevention Plan and the Spill Control plan: o Concrete Handling: Ensure all concrete washout occurs in a designated, approved, and lined washout area. o Refueling and Staging: Designated areas for construction vehicle parking, refueling, and equipment maintenance must be established with appropriate spill containment measures. o Dust Control: Use water or other approved palliatives to prevent wind transport of dust from exposed soils during grading for the new parking stalls Special Requirement #5: Oil Control The project does not meet the definition of a “High Use Site”, therefore specific oil controls are not required to be included in this project. Special Requirement #6: Aquifer Protection Area Based on review of available data, the project site does not appear to be within an Aquifer Protection Area, therefore, any special measures for aquifer protection are not required of the project. 2.3 Existing Conditions See section 1.2 for a summary of the existing site conditions. 2.4 Critical Areas The following critical areas were determined from available GIS mapping: Streams There are no streams within or adjacent to the project site. Flood Zone There are no flood zones located within the parcel boundary. Wetlands There are no existing wetlands on or near the project site. Critical Aquifer Protection Recharge Area The project site is not located within an Aquifer Protection Area. MultiCare Renton OCED Renton, Washington Preliminary Technical Information Report (TIR) 10 | P a g e Watershed Protection Areas The project site is not located within a Watershed Protection Area. High Ground Water As identified in the Geotechnical Engineering Services Report included in Appendix C, groundwater or wet soil conditions were not observed during the subsurface explorations. Groundwater monitoring is ongoing. At this time, GeoEngineers has recommended a groundwater depth of 40 feet below ground surface (about elevation 322) until the groundwater monitoring has been completed. Groundwater is not anticipated to affect the project improvements. Wells and Septic Systems There are no known wells or septic systems on-site. Fuel Tanks There are no known underground fuel tanks on the project site. Landfills There are no known closed or active landfills or contaminated sites on the project site. 2.5 Existing Soil Conditions As identified in the Geotechnical Engineering Services Report included in Appendix C, the soil explorations observed Recessional Outwash soils ranging in depth from 8.5 to 41.5 feet below ground surface. These soils generally consisted of loose to dense sand with variable silt and gravel contents. Generally speaking, Recessional Outwash soils in the upper portion of the soil profile contained a higher percentage of silt than those encountered at depth. Soils in the upper portion of the profile were loose to medium dense, and the relative consistency of their Recessional outwash tended to increase with depth. The transition between the upper Recessional Outwash soils (typically containing a higher fines content with relative constancies between loose and medium dense) and the lower Recessional Outwash soils (lower fines content and medium dense to dense) varied but typically occurred between depths of about 10 and 20 feet bgs. 3 Offsite Analysis A Level 1 analysis has been conducted per the requirements in TIR section 3. Task 1 through 4 below provide the summary of the results. 3.1 Task 1 - Study Area Definition and Maps Sub Basin: Johns Creek Catchment: ELWR Basin Name: East Lake Washington - Renton Watershed: Cedar River / Lake Washington MultiCare Renton OCED Renton, Washington Preliminary Technical Information Report (TIR) 11 | P a g e As described above, the existing storm drainage system outfalls to the existing City drainage system in Kirkland Ave NE. The system conveys runoff to the west along Sunset Blvd and ultimately outfalls into Lake Washington. No deficiencies are known within the existing private or public storm drainage system at this time. 3.2 Task 2 – Resource Review • Basin Plans: The site is in the East Lake Washington basin • Flood Hazards: The site is not located within a 100-year floodplain. • Critical Areas: While City GIS originally mapped steep slopes on-site, the project's Geotechnical Engineering Services Report confirmed these slopes are not actually present. • No other wetlands or waterbodies were identified in the immediate vicinity of the project site. Water Quality (303d list): The assumed location of the drainage basin outfall location to Lake Washington is noted on the 303d list for bacterial – fecal coliform. The project proposal will not worsen the impairment and does not propose any measures to mitigate existing drainage basin and receiving waterbody impairments. 3.3 Task 3 – Field Inspection A Level 1 inspection occurred on April 10, 2026, at 10 a.m. The weather was dry and partly sunny. • No drainage issues or problems were observed. • No existing drainage capacity issues are known at this time. • Destruction of aquatic habitat is not anticipated to be occurring on or within the vicinity of the project site. • Collection of qualitative data has been performed with the topographic survey to support the project design. The Existing Conditions Plan is located in Appendix B. 3.4 Task 4 – Drainage System Description and Problem Descriptions The system conveys runoff to the west along Sunset Blvd and ultimately outfalls into Lake Washington via varying pipe size, mainly 36” diameter. No deficiencies are known within the existing private or public storm drainage system at this time. See Appendix H for the Off-Site Analysis Drainage System Table. 3.5 Task 5 – Mitigation of Existing or Potential Problems No mitigation measures are proposed or anticipated to be required at this time. MultiCare Renton OCED Renton, Washington Preliminary Technical Information Report (TIR) 12 | P a g e 4 Special Reports and Studies A Geotechnical Engineering Services Report is included in Appendix C. 5 Other Permits Other permits that will be required for the project are: • Conditional Use Permit/SEPA Checklist • Civil Construction Permit • Building Permit 6 CSWPP Plan Analysis and Design The project CSWPPP, once completed will be included in Appendix F. 7 Bond Quantities, Facility Summaries, and Declaration of Covenant Required items will be provided following CUP approval with the construction engineering permit submittal. APPENDIX A TIR Worksheet CITY OF RENTON SURFACE WATER DESIGN MANUAL 2022 City of Renton Surface Water Design Manual 6/22/2022 8-A-1 REFERENCE 8-A TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 1 PROJECT OWNER AND PROJECT ENGINEER Part 2 PROJECT LOCATION AND DESCRIPTION Project Owner _____________________________ Phone ___________________________________ Address __________________________________ Project Engineer ___________________________ Company _________________________________ Phone ___________________________________ Project Name __________________________ CED Permit # ________________________ Location Township ________________ Range __________________ Section _________________ Site Address __________________________ Part 3 TYPE OF PERMIT APPLICATION Part 4 OTHER REVIEWS AND PERMITS Land Use (e.g., Subdivision / Short Subd.) Building (e.g., M/F / Commercial / SFR) Grading Right-of-Way Use Other _______________________ DFW HPA COE 404 DOE Dam Safety FEMA Floodplain COE Wetlands Other ________ Shoreline Management Structural Rockery/Vault/_____ ESA Section 7 Part 5 PLAN AND REPORT INFORMATION Technical Information Report Site Improvement Plan (Engr. Plans) Type of Drainage Review check one): Date (include revision dates): Date of Final: Full Targeted Simplified Large Project Directed Plan Type (check one): Date (include revision dates): Date of Final: Full Modified Simplified MultiCare Health System 315 Martin Luther King Jr Way, MultiCare Renton OCED 3116 NE Sunset Blvd, Renton, WA 98056 Tacoma, WA 98405Blake Lord, PE KPFF Consulting Engineers 425-772-7472 23 North 5 East 4 ü Conditional Use Permit (CUP) SEPA/Environmental Review ü ü ü ü REFERENCE 8: PLAN REVIEW FORMS AND WORKSHEET TECHNICAL INFORMATION REPORT (TIR) WORKSHEET 6/22/2022 2022 City of Renton Surface Water Design Manual 8-A-2 Part 6 SWDM ADJUSTMENT APPROVALS Type (circle one): Standard / Blanket Description: (include conditions in TIR Section 2) Approved Adjustment No. ______________________ Date of Approval: _______________________ Part 7 MONITORING REQUIREMENTS Monitoring Required: Yes / No Start Date: _______________________ Completion Date: _______________________ Describe: _________________________________ Re: SWDM Adjustment No. ________________ Part 8 SITE COMMUNITY AND DRAINAGE BASIN Community Plan: ____________________________________________________________________ Special District Overlays: ______________________________________________________________ Drainage Basin: _____________________________________________________________________ Stormwater Requirements: _____________________________________________________________ Part 9 ONSITE AND ADJACENT SENSITIVE AREAS River/Stream ________________________ Lake ______________________________ Wetlands ____________________________ Closed Depression ____________________ Floodplain ___________________________ Other _______________________________ Steep Slope __________________________ Erosion Hazard _______________________ Landslide Hazard ______________________ Coal Mine Hazard ______________________ Seismic Hazard _______________________ Habitat Protection ______________________ Core Requirement #8: Water Quality Cost Exemption for Parcel Redevelopment Projects Approval East Lake Washington - Renton Peak Rate Flow Control Standard (Existing Conditions) Commercial Mixed Unit (CMU) Urban Design District 'D' Overlay ü See Geotechnical Evaluation REFERENCE 8-A: TECHNICAL INFORMATION REPORT (TIR) WORKSHEET TECHNICAL INFORMATION REPORT (TIR) WORKSHEET 2022 City of Renton Surface Water Design Manual 6/22/2022 Ref 8-A-3 Part 10 SOILS Soil Type Slopes Erosion Potential High Groundwater Table (within 5 feet) Other ________________________________ Sole Source Aquifer Seeps/Springs Additional Sheets Attached Part 11 DRAINAGE DESIGN LIMITATIONS REFERENCE Core 2 – Offsite Analysis_________________ Sensitive/Critical Areas__________________ SEPA________________________________ LID Infeasibility________________________ Other________________________________ LIMITATION / SITE CONSTRAINT Additional Sheets Attached Part 12 TIR SUMMARY SHEET (provide one TIR Summary Sheet per Threshold Discharge Area) Threshold Discharge Area: name or description) Core Requirements (all 9 apply): Discharge at Natural Location Number of Natural Discharge Locations: Offsite Analysis Level: 1 / 2 / 3 dated:__________________ Flow Control (include facility summary sheet) Standard: _______________________________ or Exemption Number: ____________ Conveyance System Spill containment located at: _____________________________ Erosion and Sediment Control / Construction Stormwater Pollution Prevention CSWPP/CESCL/ESC Site Supervisor: _____________________ Contact Phone: _________________________ After Hours Phone: _________________________ Maintenance and Operation Responsibility (circle one): Private / Public If Private, Maintenance Log Required: Yes / No Financial Guarantees and Liability Provided: Yes / No Project Site Connection to existing citysystem in Kirkland Ave Ne TBD Recessional Outwash 0% - 40 %None (Fully Stabilized) ü ü ü Steep Slopes None None Infeasible. See Technical Information Report 4/10/2026 Peak Rate Flow Control Standard (Existing Conditions) N/A (Forthcoming) (Forthcoming, if required) REFERENCE 8: PLAN REVIEW FORMS AND WORKSHEET TECHNICAL INFORMATION REPORT (TIR) WORKSHEET 6/22/2022 2022 City of Renton Surface Water Design Manual 8-A-4 Part 12 TIR SUMMARY SHEET (provide one TIR Summary Sheet per Threshold Discharge Area) Water Quality (include facility summary sheet) Type (circle one): Basic / Sens. Lake / Enhanced Basic / Bog or Exemption No. _______________________ On-site BMPs Describe: Special Requirements (as applicable): Area Specific Drainage Requirements Type: SDO / MDP / BP / Shared Fac. / None Name: ________________________ Floodplain/Floodway Delineation Type (circle one): Major / Minor / Exemption / None 100-year Base Flood Elevation (or range): _______________ Datum: Flood Protection Facilities Describe: Source Control commercial / industrial land use) Describe land use: Describe any structural controls: Oil Control High-Use Site: Yes / No Treatment BMP: _________________________________ Maintenance Agreement: Yes / No with whom? _____________________________________ Other Drainage Structures Describe: Commercial No structural controls required (Forthcoming) None feasible or practicable N/A N/A N/A REFERENCE 8-A: TECHNICAL INFORMATION REPORT (TIR) WORKSHEET TECHNICAL INFORMATION REPORT (TIR) WORKSHEET 2022 City of Renton Surface Water Design Manual 6/22/2022 Ref 8-A-5 Part 13 EROSION AND SEDIMENT CONTROL REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION Clearing Limits Cover Measures Perimeter Protection Traffic Area Stabilization Sediment Retention Surface Water Collection Dewatering Control Dust Control Flow Control Control Pollutants Protect Existing and Proposed BMPs/Facilities Maintain Protective BMPs / Manage Project MINIMUM ESC REQUIREMENTS AFTER CONSTRUCTION Stabilize exposed surfaces Remove and restore Temporary ESC Facilities Clean and remove all silt and debris, ensure operation of Permanent BMPs/Facilities, restore operation of BMPs/Facilities as necessary Flag limits of sensitive areas and open space preservation areas Other _______________________ Part 14 STORMWATER FACILITY DESCRIPTIONS (Note: Include Facility Summary and Sketch) Flow Control Description Water Quality Description On-site BMPs Description Detention Infiltration Regional Facility Shared Facility Other Vegetated Flowpath Wetpool Filtration Oil Control Spill Control Other Full Dispersion Full Infiltration Limited Infiltration Rain Gardens Bioretention Permeable Pavement Basic Dispersion Soil Amendment Perforated Pipe Connection Other ü ü ü ü ü ü ü ü ü ü ü ü ü ü ü Existing ConcreteVault REFERENCE 8: PLAN REVIEW FORMS AND WORKSHEET TECHNICAL INFORMATION REPORT (TIR) WORKSHEET 6/22/2022 2022 City of Renton Surface Water Design Manual 8-A-6 Part 15 EASEMENTS/TRACTS Part 16 STRUCTURAL ANALYSIS Drainage Easement Covenant Native Growth Protection Covenant Tract Other ____________________________ Cast in Place Vault Retaining Wall Rockery > 4 High Structural on Steep Slope Other _______________________________ Part 17 SIGNATURE OF PROFESSIONAL ENGINEER I, or a civil engineer under my supervision, have visited the site. Actual site conditions as observed were incorporated into this worksheet and the attached Technical Information Report. To the best of my knowledge the information provided here is accurate. Signed/Date 5/4/2026 APPENDIX B Civil CUP Application Plan Sheet MULTICARE RENTON OFF-CAMPUS EMERGENCY DEPARTMENT (OCED) CONDITIONAL USE PERMIT (CUP) SET RENTON, WASHINGTON SITE DATA: ADDRESS: 3116 SUNSET BLVD NE RENTON, WA 98056 PARCEL NUMBER: KING COUNTY APN 042305-9095 LOT SIZE: 76,483 SF (1.76 AC) JURISDICTION: CITY OF RENTON ZONING: CENTER VILLAGE (CV) OWNER: MULTICARE HEALTH SYSTEM 315 MARTIN LUTHER KING JR WAY TACOMA, WA 98405 (509) 473-7884 CONTACT: SHELLY ROMANYSZYN PROJECT MANAGER/OWNER REPRESENTATIVE: EMERUS 8686 NEW TRAILS DRIVE, SUITE 100 THE WOODLANDS, TX 77381 CONTACT: ZACH ISBELL JLL PROJECT & DEVELOPMENT SERVICES 601 UNION STREET, SUITE 2800 SEATTLE, WA 98101 TEL: (206) 794-4296 CONTACT: CHRISTINE JESSE CIVIL ENGINEER: KPFF CONSULTING ENGINEERS 640 WOODLAND SQUARE LOOP SE, SUITE 100 LACEY, WA 98503 TEL:(360) 292-7230 CONTACT: BLAKE LORD, PE ARCHITECT: CLARK KJOS ARCHITECTS (CKA) 421 SW SIXTH AVENUE, SUITE 1300 PORTLAND, OR 97204 TEL:(530) 206-3822 CONTACT: SCOT JAHN GEOTECHNICAL ENGINEER: GEOENGINEERS 1145 BROADWAY, SUITE 300 TACOMA, WA 98402 TEL:(253) 383-4940 CONTACT: BRETT E. LARABEE, PE TRANSPORTATION/LIGHTING ENGINEER: TRANSPORATION ENGINEERING NORTHWEST (TENW) 520 KIRKLAND WAY KIRKLAND, WA 98033 TEL:(425) 327-1016 CONTACT: SPENSER HAYNIE VICINITY MAP NTS VERTICAL DATUM NAVD 88 BASIS OF BEARING WASHINGTON STATE PLANE COORDINATE SYSTEM, NAD 83/91 NORTH ZONE 4601 APPROX APPROXIMATELY AR AIR RELEASE AVE AVENUE BCR BEGINNING OF CURB RETURN BLDG BUILDING BLVD BOULEVARD BO BLOW-OFF CB CATCH BASIN CO CLEANOUT CONC CONCRETE CPP CORRUGATED POLYETHYLENE PIPE DCDA DOUBLE CHECK DETECTOR ASSEMBLY DCVA DOUBLE CHECK VALVE ASSEMBLY DI DUCTILE IRON DIA DIAMETER DIP DUCTILE IRON PIPE DWG DRAWING E EAST, EASTING ECP END OF CURB RETURN EL, ELEV ELEVATION EP EDGE OF PAVEMENT EX EXISTING FDC FIRE DEPARTMENT CONNECTION FF FINISHED FLOOR FL FLOW LINE FM FORCE MAIN FT FEET GA GAUGE GRVL GRAVEL HDPE HIGH DENSITY POLYETHYLENE HORIZ, HORZ HORIZONTAL IE INVERT ELEVATION LF LINEAR FEET MAX MAXIMUM MECH MECHANICAL MIN MINIMUM MJ MECHANICAL JOINT N NORTH, NORTHING NE NORTHEAST NIC NOT IN CONTRACT NTS NOT TO SCALE NW NORTHWEST PC POINT OF CURVE PI POINT OF TANGENT INTERSECTION PIV PRESSURE INDUCING VALVE POC POINT OF CONNECTION PT POINT OF TANGENT PVC POLYVINYL CHLORIDE R RANGE, RADIUS RPBA REDUCED PRESSURE BACKFLOW ASSEMBLY RD ROOF DRAIN, ROAD ROW RIGHT OF WAY S SOUTH, SLOPE SCH SCHEDULE SE SOUTHEAST SEC SECTION SF SQUARE FEET SD STORM DRAIN SS SANITARY SEWER SSMH SEWER MANHOLE ST STREET STA STATION STD STANDARD SW SOUTHWEST T TOWNSHIP TYP TYPICAL VERT VERTICAL VC VERTICAL CURVE VPC VERTICAL POINT OF CURVE VPT VERTICAL POINT OF TANGENT W WEST W/WITH WM WATER MAIN ABBREVIATIONS: CALL BEFORE YOU DIG DE S I G N E D B Y AP P R O V E D B Y JO B N O : DR A W N B Y CH E C K E D B Y DA T E DRAWING SHEET OF CA L L UN D E R G R O U N D LO C A T E T W O ( 2 ) WO R K I N G D A Y S BE F O R E Y O U DI G 81 1 64 0 W o o d l a n d S q u a r e L o o p , Su i t e 1 0 0 La c e y , W A 9 8 5 0 3 36 0 . 2 9 2 . 7 2 3 0 ww w . k p f f . c o m CH D AP P R BY DA T E NO RE V I S I O N P R O F ESSIONAL E N G I NEER REGI S T E R E D T O S AT E O F WASHIN GT N 5/ 4 / 2 0 2 6 B L A K E A . L O R D 8 SECTION 4, TOWNSHIP 23 NORTH, RANGE 5 EAST, W.M. KING COUNTY , WASHINGTON RE N T O N , W A CUP PERMIT SET 10 1 8 2 6 0 0 0 1 5 KK KK BA L 5/ 4 / 2 0 2 6 CL L MU L T I C A R E R E N T O N O C E D CIVIL SHEET INDEX SHEET DWG TITLE 1 C1.0 COVER SHEET 2 C1.1 GENERAL NOTES 3 C2.0 EXISTING CONDITIONS 4 C3.0 TESC & DEMO PLAN 5 C4.0 SITE PLAN 6 C5.0 UTILITY PLAN 7 C6.0 GRADING & DRAINAGE PLAN 8 C7.0 VEHICLE TRACKING 1 C1.0 CO V E R S H E E T NE S u n s e t B l v d NE 12th StEd m o n d s A v e N E Ki r k l a n d A v e N E PROJECT SITE NE 10th St 900 NE 12TH ST KI R K L A N D A V E N E HIG H W A Y 9 0 0 / N E S U N S E T B L V D PARCEL NO. 042305-9095 (1.76 AC) 3116 SUNSET BLVD NE RENTON, WA 98056 OWNER: MULTICARE HEALTH SYSTEM PARCEL NO. 722780-0265 1222 KIRKLAND AVE NE RENTON, WA 98056 OWNER: MEADOW HIGHLANDS LLC PARCEL NO. 722780-0266 3101 NE 13TH ST RENTON, WA 98056 OWNER: SENSET MILES LLC PARCEL NO. 042305-9080 3160 SUNSET BLVD NE RENTON, WA 98056 OWNER: LOUIE FAMILY LLC SCALE 0 40 80 PROPERTY LINE (TYP) SURVEYOR: KPFF CONSULTING ENGINEERS 640 WOODLAND SQUARE LOOP SE, SUITE 100 LACEY, WA 98503 TEL:(360) 292-7230 CONTACT: JEREME CHAPMAN, PLS LANDSCAPE ARCHITECT: DELA STUDIO 9024 N GENEVA AVENUE PORTLAND, OR 97203 TEL:(503) 278-2536 CONTACT: DANIEL EDWARDS MEP ENGINEER: PAE ENGINEERS 1011 WESTERN AVE, SUITE 500 SEATTLE, WA 98104 TEL:(206) 413-8469 ROW CENTERLINE (TYP) ROW LINE (TYP) DE S I G N E D B Y AP P R O V E D B Y JO B N O : DR A W N B Y CH E C K E D B Y DA T E DRAWING SHEET OF CA L L UN D E R G R O U N D LO C A T E T W O ( 2 ) WO R K I N G D A Y S BE F O R E Y O U DI G 81 1 64 0 W o o d l a n d S q u a r e L o o p , Su i t e 1 0 0 La c e y , W A 9 8 5 0 3 36 0 . 2 9 2 . 7 2 3 0 ww w . k p f f . c o m CH D AP P R BY DA T E NO RE V I S I O N P R O F ESSIONAL E N G I NEER REGI S T E R E D T O S AT E O F WASHIN GT N 5/ 4 / 2 0 2 6 B L A K E A . L O R D 8 SECTION 4, TOWNSHIP 23 NORTH, RANGE 5 EAST, W.M. KING COUNTY , WASHINGTON RE N T O N , W A CUP PERMIT SET 10 1 8 2 6 0 0 0 1 5 KK KK BA L 5/ 4 / 2 0 2 6 CL L MU L T I C A R E R E N T O N O C E D 2 C1.1 GE N E R A L N O T E S CITY OF RENTON SURFACE WATER GENERAL NOTES: 1.BEFORE ANY CONSTRUCTION OR DEVELOPMENT ACTIVITY OCCURS, A PRE-CONSTRUCTION MEETING SHALL BE HELD AMONG THE CITY OF RENTON, HEREBY REFERRED TO AS THE CITY, THE APPLICANT, AND THE APPLICANT'S CONTRACTOR. 2.THE APPLICANT SHALL BE RESPONSIBLE FOR SECURING ALL NECESSARY CITY, STATE, AND FEDERAL PERMITS PRIOR TO CONSTRUCTION. 3.ALL STORM DRAINAGE IMPROVEMENTS SHALL BE DESIGNED AND CONSTRUCTED IN ACCORDANCE WITH THE LATEST EDITION OF THE CITY OF RENTON SURFACE WATER DESIGN MANUAL (RENTON SWDM), RENTON MUNICIPAL CODE (RMC), AND THE STANDARD SPECIFICATIONS FOR ROAD, BRIDGE AND MUNICIPAL CONSTRUCTION PREPARED BY WSDOT AND THE AMERICAN PUBLIC WORKS ASSOCIATION (APWA). IT SHALL BE THE SOLE RESPONSIBILITY OF THE APPLICANT TO CORRECT ANY ERROR, OMISSION OR VARIATION FROM THE ABOVE REQUIREMENTS FOUND IN THE PLANS. ALL CORRECTIONS SHALL BE AT NO ADDITIONAL COST TO THE CITY. 4.APPROVAL OF THE ROAD, GRADING, PARKING, BUILDING, AND DRAINAGE PLAN DOES NOT CONSTITUTE AS APPROVAL OF ANY OTHER CONSTRUCTION (E.G. WATER, SEWER, GAS, ELECTRICAL. ETC.). PLANS FOR STRUCTURES SUCH AS BRIDGES, VAULTS, AND RETAINING WALLS REQUIRE A SEPARATE REVIEW AND APPROVAL BY THE CITY PRIOR TO CONSTRUCTION. THE SURFACE WATER DRAINAGE SYSTEM SHALL BE CONSTRUCTED ACCORDING TO THE APPROVED PLANS. ANY DEVIATION FROM THE APPROVED PLANS WILL REQUIRE COORDINATION FOLLOWED BY WRITTEN APPROVAL FROM THE CITY. 5.A COPY OF THE APPROVED PLANS SHALL BE ON THE JOB SITE WHENEVER CONSTRUCTION IS IN PROGRESS. 6.THE LOCATIONS OF ALL EXISTING UTILITIES SHOWN HEREON HAVE BEEN ESTABLISHED BY FIELD SURVEY OR OBTAINED FROM AVAILABLE RECORDS AND SHALL THEREFORE BE CONSIDERED APPROXIMATE ONLY AND NOT NECESSARILY COMPLETE. IT IS THE SOLE RESPONSIBILITY OF THE APPLICANT AND THE APPLICANT'S CONTRACTOR TO INDEPENDENTLY VERIFY THE ACCURACY OF ALL UTILITY LOCATIONS SHOWN, AND TO FURTHER DISCOVER AND AVOID ANY OTHER UTILITIES NOT SHOWN HEREON THAT MAY BE AFFECTED BY THE IMPLEMENTATION OF THIS PLAN. THE APPLICANT SHALL RECORD ON THE AS-BUILT DRAWINGS ALL UNDOCUMENTED UTILITIES DISCOVERED AND ANY CHANGES TO THE APPROVED PLANS. THE APPLICANT SHALL IMMEDIATELY NOTIFY THE ENGINEER OF RECORD IF A CONFLICT EXISTS. 7.VERTICAL DATUM SHALL BE NAVD 88 AND HORIZONTAL DATUM SHALL BE NAD 83 (WA STATE PLANE, NORTH), UNLESS OTHERWISE APPROVED BY THE CITY. REFERENCE BENCHMARK, DATUM, AND ELEVATIONS SHALL BE NOTED ON THE PLANS. 8.ALL UTILITY TRENCH BACKFILL AND ROADWAY SUBGRADE SHALL BE COMPACTED TO 95% MAXIMUM DRY DENSITY PER SECTION 2-03.3(14)D - COMPACTION AND MOISTURE CONTROL TESTS OF THE WSDOT STANDARD SPECIFICATIONS. IN PERMEABLE PAVEMENT AND OTHER INFILTRATION AREAS, ALL TRENCH BACKFILL SHALL BE FIRM AND UNYIELDING BUT IN NO CASE SHALL BE COMPACTED TO MORE THAN 92% OF MAXIMUM DRY DENSITY. 9.OPEN CUTTING OF EXISTING ROADWAYS FOR STORM DRAINAGE WORK IS NOT ALLOWED UNLESS SPECIFICALLY APPROVED BY THE CITY AND NOTED ON THESE APPROVED PLANS. ANY OPEN CUT SHALL BE RESTORED IN ACCORDANCE WITH THE CITY TRENCH RESTORATION STANDARDS. 10.ALL PIPE AND STRUCTURES SHALL BE STAKED FOR SURVEY LINE AND GRADE PRIOR TO THE START OF CONSTRUCTION. WHERE SHOWN ON THE PLANS OR WHERE DIRECTED BY THE CITY, THE EXISTING MANHOLES, CATCH BASINS, OR INLETS SHALL BE ADJUSTED TO THE GRADE AS STAKED. 11.ALL FLOW CONTROL FACILITIES SHALL BE INSTALLED AND IN OPERATION PRIOR TO, OR IN CONJUNCTION WITH, ANY CONSTRUCTION ACTIVITY UNLESS OTHERWISE APPROVED BY THE CITY. 12.ALL PIPE AND APPURTENANCES SHALL BE LAID ON A PROPERLY PREPARED FOUNDATION IN ACCORDANCE WITH THE CURRENT STATE OF WASHINGTON STANDARD SPECIFICATION FOR ROAD AND BRIDGE CONSTRUCTION. THIS SHALL INCLUDE NECESSARY LEVELING OF THE TRENCH BOTTOM OR THE TOP OF THE FOUNDATION MATERIAL, AS WELL AS PLACEMENT AND COMPACTION OF REQUIRED BEDDING MATERIAL TO UNIFORM GRADE SO THAT THE ENTIRE LENGTH OF THE PIPE WILL BE SUPPORTED ON A UNIFORMLY DENSE, UNYIELDING BASE. ALL PIPE BEDDING AND BACKFILL SHALL BE AS SHOWN ON THE CITY STANDARD PLAN 220.00, 220.10, AND 220.20. 13.STEEL PIPE SHALL BE ALUMINIZED, OR GALVANIZED WITH ASPHALT TREATMENT 1, 2, OR 5 INSIDE AND OUTSIDE. 14.ALL DRAINAGE STRUCTURES SUCH AS CATCH BASINS AND MANHOLES SHALL BE FITTED WITH DUCTILE IRON, BOLT-LOCKING LIDS PER THE CITY STANDARD PLAN 204.10, 204.20, 204.30, 204.40, AND 204.50. STRUCTURES SHALL HAVE: ·RECTANGULAR OR ROUND, SOLID LIDS WHEN NOT COLLECTING RUNOFF, AND OUTSIDE OF THE ROADWAY. ·ROUND, SOLID LIDS WHEN NOT COLLECTING RUNOFF, AND LOCATED WITHIN THE ROADWAY, BUT OUTSIDE OF THE CURB/GUTTER LINE. ·ROUND, SOLID LIDS DISPLAYING THE CITY LOGO WHEN WITHIN THE PUBLIC RIGHT-OF-WAY OR IN AN EASEMENT TO THE CITY. PRIVATE STRUCTURE LIDS OUTSIDE PUBLIC RIGHT-OF-WAY AND EASEMENTS TO THE CITY SHALL NOT DISPLAY THE CITY LOGO. 15.BUILDINGS AND OTHER STRUCTURES SHALL BE PLACED IN ACCORDANCE WITH TABLE 4.1 EASEMENT WIDTHS AND BUILDING SETBACKS LINES OF THE RENTON SWDM. 16.LIDS OF MANHOLES/CATCH BASINS WITHIN PUBLIC RIGHT-OF-WAY SHALL NOT BE ADJUSTED TO FINAL GRADE UNTIL AFTER PAVING. ALL MANHOLE/CATCH BASIN RIMS SHALL BE ADJUSTED TO BE FLUSH WITH FINAL FINISHED GRADES, UNLESS OTHERWISE SHOWN. 17.ALL DRIVEWAY CULVERTS LOCATED WITHIN CITY RIGHT-OF-WAY SHALL BE OF SUFFICIENT LENGTH TO PROVIDE A MINIMUM 3:1 SLOPE FROM THE EDGE OF THE DRIVEWAY TO THE BOTTOM OF THE DITCH. 18.ROCK FOR EROSION PROTECTION OF ROADSIDE DITCHES, WHERE REQUIRED, SHALL BE OF SOUND QUARRY ROCK PLACED TO A MINIMUM DEPTH OF ONE (1) FOOT AND SHALL MEET THE FOLLOWING SPECIFICATIONS: ·4 - 8 INCH ROCK / 40 - 70% PASSING; ·2 - 4 INCH ROCK / 30 - 40% PASSING; AND ·LESS THAN 2 INCH ROCK / 10 - 20% PASSING. 19.FOOTING DRAINAGE SYSTEMS AND ROOF DOWNSPOUT SYSTEMS SHALL NOT BE INTERCONNECTED AND SHALL SEPARATELY CONVEY COLLECTED FLOWS TO THE CONVEYANCE SYSTEM OR FLOW CONTROL FACILITY ON THE SITE, UNLESS APPROVED BY THE CITY. FOOTING DRAINS SHALL NOT BE CONNECTED TO ON-SITE BMPS. 20.THE END OF EACH STORM DRAIN STUB SHALL BE CAPPED. A CLEANOUT TOPPED WITH A BOLT-LOCKING LID MARKED "STORM” OR "DRAIN" SHALL BE LOCATED AT THE PROPERTY LINE OR AT THE POINT OF CONNECTION OF A PRIVATE STORM DRAINAGE CONVEYANCE SYSTEM PER THE CITY STANDARD PLAN 227.00. 21.ALL STORM SYSTEM EXTENSIONS SHALL BE STAKED FOR LINE AND GRADE BY A SURVEYOR LICENSED IN WASHINGTON STATE, AND CUT SHEETS SHALL BE PROVIDED TO THE CITY PRIOR TO CONSTRUCTION. 22.ALL NEWLY-INSTALLED AND NEWLY-REHABILITATED (PUBLIC AND PRIVATE) STORM CONVEYANCE SYSTEMS SHALL BE INSPECTED BY MEANS OF REMOTE CCTV ACCORDING TO THE CITY STANDARD PLAN 266.00. CCTV INSPECTIONS AND REPORTS SHALL BE SUBMITTED TO THE CITY PRIOR TO RECEIVING APPROVAL TO INSTALL PROJECT CURBS, GUTTERS AND/OR PAVEMENT. 23.ALL STORM SYSTEMS AND CONNECTIONS TO EXISTING MAINS SHALL BE TESTED IN ACCORDANCE WITH SECTION 7-04.3(1) OF THE WSDOT STANDARD SPECIFICATIONS AND IN THE PRESENCE OF A REPRESENTATIVE OF THE CITY. STORM DRAIN STUBS SHALL BE TESTED FOR ACCEPTANCE AT THE SAME TIME THE MAIN STORM IS TESTED. 24.FOR ALL DISTURBED PERVIOUS AREAS (COMPACTED, GRADED, LANDSCAPED, ETC.) OF THE DEVELOPMENT SITE, TO MAINTAIN THE MOISTURE CAPACITY OF THE SOIL EITHER STOCKPILE AND REDISTRIBUTE THE EXISTING DUFF LAYER AND NATIVE TOPSOIL OR AMEND THE SOIL WITH COMPOST IN ACCORDANCE WITH STANDARD PLAN 264.00. 25.ISSUANCE OF THE BUILDING OR CONSTRUCTION PERMITS BY THE CITY DOES NOT RELIEVE THE APPLICANT OF THE CONTINUING LEGAL OBLIGATION AND/OR LIABILITY CONNECTED WITH STORMWATER DISPOSAL. THE CITY DOES NOT ACCEPT ANY OBLIGATION FOR THE PROPER FUNCTIONING AND MAINTENANCE OF THE STORM SYSTEM PROVIDED DURING CONSTRUCTION. 26.ADEQUATE SAFEGUARDS, SAFETY DEVICES, PROTECTIVE EQUIPMENT, FLAGGERS, AND ANY OTHER ACTIONS NEEDED TO PROTECT THE LIFE, HEALTH, AND SAFETY OF THE PUBLIC, AND TO PROTECT PROPERTY IN CONNECTION WITH THE PERFORMANCE OF WORK SHALL BE PROVIDED. ANY WORK WITHIN THE TRAVELED RIGHT-OF-WAY THAT MAY INTERRUPT NORMAL TRAFFIC FLOW SHALL REQUIRE A TRAFFIC CONTROL PLAN APPROVED BY THE CITY. ALL SECTIONS OF THE WSDOT STANDARD SPECIFICATIONS 1-10 TEMPORARY TRAFFIC CONTROL SHALL APPLY. 27.PROJECTS LOCATED WITHIN THE CITY'S AQUIFER PROTECTION AREA (APA) SHALL COMPLY WITH SPECIAL REQUIREMENT #6 OF THE RENTON SWDM AND AQUIFER PROTECTION REGULATIONS (RMC 4-3-050). 28.PLACEMENT OF SURFACE APPURTENANCES (CATCH BASIN/MANHOLE LIDS, CLEANOUTS, INLETS, ETC.) IN THE STREET TRAVEL LANE WHEEL PATH, INTERSECTIONS OF STREET TRAVEL LANES, BIKE LANES, SIDEWALKS, AND CROSSWALKS SHALL BE AVOIDED WHENEVER POSSIBLE. ANY SURFACE APPURTENANCE PLACED IN A SIDEWALK OR CROSSWALK SHALL BE FITTED WITH A NON-SLIP OR NON-SKID LID PER ADA REQUIREMENTS. 29.CLEARLY LABEL PUBLIC AND PRIVATE SYSTEMS ON THE PLANS. PRIVATE SYSTEMS SHALL BE MAINTAINED BY THE APPLICANT. 30.MINIMUM COVER OVER STORM DRAINAGE PIPE SHALL CONFORM TO TABLE 4.2.1.A2 OF THE RENTON SWDM. 31.CONSTRUCTED PERMEABLE PAVEMENT SHALL BE PERMEABLE ENOUGH TO ABSORB WATER AT A MINIMUM RATE OF 20 INCHES PER HOUR IMMEDIATELY AFTER THE PAVEMENT SURFACE HAS BEEN WETTED CONTINUOUSLY FOR AT LEAST 10 MINUTES. COMPLIANCE WITH THIS MINIMUM RATE SHALL BE CHECKED PRIOR TO CONSTRUCTION APPROVAL OF THE PAVEMENT. COMPLIANCE MAY BE CHECKED USING A SIMPLE BUCKET TEST IN WHICH 5 GALLONS OF WATER IS POURED ONTO THE PAVEMENT SURFACE ALL AT ONCE. IF ONLY A MINOR AMOUNT OF WATER PONDS OR RUNS OFF THE SURFACE, THEN THE PAVEMENT IS CONSIDERED TO MEET THE MINIMUM RATE OF ABSORPTION. AT LEAST ONE TEST SHALL BE CONDUCTED PER 1,000 SQUARE FEET OF PERMEABLE PAVEMENT. IF THIS TEST IS NOT CONCLUSIVE, THEN ANOTHER TEST PER ASTM C1701 SHALL BE CONDUCTED. FOR LARGE AREAS (E.G., PARKING AREAS), TESTING OBSERVATION MAY BE ACCOMPLISHED WHILE WALKING BEHIND A SLOWLY MOVING WATER TRUCK DISCHARGING WATER AT A RATE SIMILAR TO THE BUCKET TEST. PERMEABLE PAVERS SHALL BE TESTED USING ASTM C1781. CITY OF RENTON TESC GENERAL NOTES: 1.BEFORE ANY CONSTRUCTION OR DEVELOPMENT ACTIVITY OCCURS, A PRE-CONSTRUCTION MEETING SHALL BE HELD AMONG THE CITY OF RENTON, HEREBY REFERRED TO AS THE CITY, THE APPLICANT, AND THE APPLICANT'S CONTRACTOR. 2.THE APPLICANT IS RESPONSIBLE FOR OBTAINING THE WASHINGTON STATE DEPARTMENT OF ECOLOGY (ECOLOGY) CONSTRUCTION STORMWATER GENERAL PERMIT, IF IT IS REQUIRED FOR THE PROJECT. THE APPLICANT SHALL PROVIDE THE CITY COPIES OF ALL MONITORING REPORTS PROVIDED TO ECOLOGY ASSOCIATED WITH THE CONSTRUCTION STORMWATER GENERAL PERMIT. 3.THE ESC PLAN SET SHALL INCLUDE AN ESC CONSTRUCTION SEQUENCE DETAILING THE ORDERED STEPS THAT SHALL BE FOLLOWED FROM CONSTRUCTION COMMENCEMENT TO POST-PROJECT CLEANUP IN ORDER TO FULFILL PROJECT ESC REQUIREMENTS. 4.THE BOUNDARIES OF THE CLEARING LIMITS, SENSITIVE AREAS AND THEIR BUFFERS, AND AREAS OF VEGETATION PRESERVATION AND TREE RETENTION AS PRESCRIBED ON THE PLAN(S) SHALL BE CLEARLY DELINEATED BY FENCING AND PROTECTED IN THE FIELD IN ACCORDANCE WITH APPENDIX D OF THE CITY OF RENTON SURFACE WATER DESIGN MANUAL (RENTON SWDM) PRIOR TO THE START OF CONSTRUCTION. DURING THE CONSTRUCTION PERIOD, NO DISTURBANCE BEYOND THE CLEARING LIMITS SHALL BE PERMITTED. THE CLEARING LIMITS SHALL BE MAINTAINED BY THE APPLICANT/ESC SUPERVISOR FOR THE DURATION OF CONSTRUCTION. 5.STABILIZED CONSTRUCTION ENTRANCES SHALL BE INSTALLED AT THE BEGINNING OF CONSTRUCTION AND MAINTAINED FOR THE DURATION OF THE PROJECT. ADDITIONAL MEASURES, SUCH AS CONSTRUCTED WHEEL WASH SYSTEMS OR WASH PADS, MAY BE REQUIRED TO ENSURE THAT ALL PAVED AREAS ARE KEPT CLEAN AND TRACK-OUT TO ROAD RIGHT OF WAY DOES NOT OCCUR FOR THE DURATION OF THE PROJECT. IF SEDIMENT IS TRACKED OFFSITE, PUBLIC ROADS SHALL BE CLEANED THOROUGHLY AT THE END OF EACH DAY, OR MORE FREQUENTLY DURING WET WEATHER, AS NECESSARY TO PREVENT SEDIMENT FROM ENTERING WATERS OF THE STATE. 6.WASHOUT FROM CONCRETE TRUCKS SHALL BE PERFORMED OFF-SITE OR IN DESIGNATED CONCRETE WASHOUT AREAS ONLY. DO NOT WASH OUT CONCRETE TRUCKS ONTO THE GROUND, OR TO STORM DRAINS OR OPEN DITCHES. ON-SITE DUMPING OF EXCESS CONCRETE SHALL ONLY OCCUR IN DESIGNATED CONCRETE WASHOUT AREAS. 7.ALL REQUIRED ESC BMPS SHALL BE CONSTRUCTED AND IN OPERATION PRIOR TO LAND CLEARING AND/OR CONSTRUCTION TO PREVENT TRANSPORTATION OF SEDIMENT TO SURFACE WATER, DRAINAGE SYSTEMS AND ADJACENT PROPERTIES. ALL ESC BMPS SHALL BE MAINTAINED IN A SATISFACTORY CONDITION UNTIL SUCH TIME THAT CLEARING AND/OR CONSTRUCTION IS COMPLETE AND POTENTIAL FOR ON-SITE EROSION HAS PASSED. ALL ESC BMPS SHALL BE REMOVED AFTER CONSTRUCTION IS COMPLETED AND THE SITE HAS BEEN STABILIZED TO ENSURE POTENTIAL FOR ON-SITE EROSION DOES NOT EXIST. THE IMPLEMENTATION, MAINTENANCE, REPLACEMENT, ENHANCEMENT, AND REMOVAL OF ESC BMPS SHALL BE THE RESPONSIBILITY OF THE APPLICANT. 8.ANY HAZARDOUS MATERIALS OR LIQUID PRODUCTS THAT HAVE THE POTENTIAL TO POLLUTE RUNOFF SHALL BE DISPOSED OF PROPERLY. 9.THE ESC BMPS DEPICTED ON THIS DRAWING ARE INTENDED TO BE MINIMUM REQUIREMENTS TO MEET ANTICIPATED SITE CONDITIONS. AS CONSTRUCTION PROGRESSES AND UNEXPECTED OR SEASONAL CONDITIONS DICTATE, THE APPLICANT SHALL ANTICIPATE THAT MORE ESC BMPS WILL BE NECESSARY TO ENSURE COMPLETE SILTATION CONTROL ON THE PROPOSED SITE. DURING THE COURSE OF CONSTRUCTION, IT SHALL BE THE OBLIGATION AND RESPONSIBILITY OF THE APPLICANT TO ADDRESS ANY NEW CONDITIONS THAT MAY BE CREATED BY THE ACTIVITIES AND TO PROVIDE ADDITIONAL ESC BMPS, OVER AND ABOVE MINIMUM REQUIREMENTS, AS MAY BE NEEDED, TO PROTECT ADJACENT PROPERTIES AND WATER QUALITY OF THE RECEIVING DRAINAGE SYSTEM. 10.APPROVAL OF THIS PLAN IS FOR ESC ONLY. IT DOES NOT CONSTITUTE AN APPROVAL OF STORM DRAINAGE DESIGN, SIZE NOR LOCATION OF PIPES, RESTRICTORS, CHANNELS, OR STORMWATER FACILITIES. 11.ANY DEWATERING SYSTEM NECESSARY FOR THE CONSTRUCTION OF STORMWATER FACILITIES SHALL BE SUBMITTED TO THE CITY FOR REVIEW AND APPROVAL. 12.ANY AREAS OF EXPOSED SOILS, INCLUDING ROADWAY EMBANKMENTS, THAT WILL NOT BE DISTURBED FOR TWO DAYS DURING THE WET SEASON (OCTOBER 1ST THROUGH APRIL 30TH) OR SEVEN DAYS DURING THE DRY SEASON (MAY 1ST THROUGH SEPTEMBER 30TH) SHALL BE IMMEDIATELY STABILIZED WITH THE APPROVED ESC COVER METHODS (E.G., SEEDING, MULCHING, PLASTIC COVERING, ETC.) IN CONFORMANCE WITH APPENDIX D OF THE RENTON SWDM. 13.WET SEASON ESC REQUIREMENTS APPLY TO ALL CONSTRUCTION SITES BETWEEN OCTOBER 1ST AND APRIL 30TH, UNLESS OTHERWISE APPROVED BY THE CITY. 14.ANY AREA NEEDING ADDITIONAL ESC MEASURES, NOT REQUIRING IMMEDIATE ATTENTION, SHALL BE ADDRESSED WITHIN SEVEN (7) DAYS. 15.THE ESC BMPS ON INACTIVE SITES SHALL BE INSPECTED AND MAINTAINED AT A MINIMUM OF ONCE A MONTH OR WITHIN 24 HOURS FOLLOWING A STORM EVENT. INSPECTION AND MAINTENANCE SHALL OCCUR MORE FREQUENTLY AS REQUIRED BY THE CITY. 16.BEFORE COMMENCEMENT OF ANY CONSTRUCTION ACTIVITY, CATCH BASIN INSERTS PER THE CITY STANDARD PLAN 216.30 SHALL BE PROVIDED FOR ALL STORM DRAIN INLETS DOWNSLOPE AND WITHIN 500 FEET OF A DISTURBED OR CONSTRUCTION AREA, UNLESS THE RUNOFF THAT ENTERS THE INLET WILL BE CONVEYED TO A SEDIMENT POND OR TRAP. ALL CATCH BASIN INSERTS SHALL BE PERIODICALLY INSPECTED AND REPLACED AS NECESSARY TO ENSURE FULLY FUNCTIONING CONDITION. 17.AT NO TIME SHALL SEDIMENT ACCUMULATION EXCEED 2/3 OF THE CAPACITY OF THE CATCH BASIN SUMP. ALL CATCH BASINS AND CONVEYANCE LINES SHALL BE CLEANED PRIOR TO PAVING. THE CLEANING OPERATION SHALL NOT FLUSH SEDIMENT-LADEN WATER INTO THE DOWNSTREAM SYSTEM. 18.ANY PERMANENT STORMWATER FACILITY LOCATION USED AS A TEMPORARY SETTLING BASIN SHALL BE MODIFIED WITH THE NECESSARY ESC BMPS AND SHALL PROVIDE ADEQUATE STORAGE CAPACITY. IF THE TEMPORARY FACILITY IS TO ULTIMATELY FUNCTION AS AN INFILTRATION SYSTEM IN ITS PERMANENT STATE, THE TEMPORARY FACILITY SHALL BE ROUGH GRADED SO THAT THE BOTTOM AND SIDES ARE AT LEAST THREE FEET ABOVE THE FINAL GRADE OF THE PERMANENT FACILITY. 19.AREAS DESIGNATED ON THE PLAN(S) CONTAINING EXISTING STORMWATER FACILITIES OR ON-SITE BMPS (AMENDED SOILS, BIORETENTION, PERMEABLE PAVEMENT, ETC.) SHALL BE CLEARLY FENCED AND PROTECTED USING ESC BMPS TO AVOID SEDIMENTATION AND COMPACTION DURING CONSTRUCTION. 20.PRIOR TO THE BEGINNING OF THE WET SEASON (OCTOBER 1ST), ALL DISTURBED AREAS SHALL BE INSPECTED TO IDENTIFY WHICH ONES SHALL BE SODDED OR SEEDED IN PREPARATION FOR THE WINTER RAINS. DISTURBED AREAS SHALL BE SODDED OR SEEDED WITHIN ONE WEEK OF THE BEGINNING OF THE WET SEASON. AN EXHIBIT OF THOSE AREAS TO BE SODDED OR SEEDED AND THOSE AREAS TO REMAIN UNCOVERED SHALL BE SUBMITTED TO THE CITY FOR REVIEW. 21.PRIOR TO FINAL CONSTRUCTION ACCEPTANCE, THE PROJECT SITE SHALL BE STABILIZED TO PREVENT SEDIMENT-LADEN WATER FROM LEAVING THE PROJECT SITE, ALL ESC BMPS SHALL BE REMOVED, AND STORMWATER CONVEYANCE SYSTEMS, FACILITIES, AND ON-SITE BMPS SHALL BE RESTORED TO THEIR FULLY FUNCTIONING CONDITION. ALL DISTURBED AREAS OF THE PROJECT SITE SHALL BE VEGETATED OR OTHERWISE PERMANENTLY STABILIZED. AT A MINIMUM, DISTURBED AREAS SHALL BE SODDED OR SEEDED AND MULCHED TO ENSURE THAT SUFFICIENT COVER WILL DEVELOP SHORTLY AFTER FINAL APPROVAL. MULCH WITHOUT SEEDING IS ADEQUATE FOR AREAS TO BE LANDSCAPED BEFORE OCTOBER 1ST. 22.ROCKERIES ARE CONSIDERED TO BE A METHOD OF BANK STABILIZATION AND EROSION CONTROL. ROCKERIES SHALL NOT BE CONSTRUCTED TO SERVE AS RETAINING WALLS. ALL ROCKERIES IN CITY ROAD RIGHTS-OF-WAY SHALL BE CONSTRUCTED IN ACCORDANCE WITH CITY STANDARDS. ROCKERIES OUTSIDE OF ROAD RIGHTS-OF-WAY SHALL BE CONSTRUCTED IN ACCORDANCE WITH THE INTERNATIONAL BUILDING CODE. KPFF SURVEY GENERAL NOTES: 1.BASIS OF MERIDIAN WASHINGTON STATE PLANE COORDINATES SYSTEM, NAD 83/91, NORTH ZONE 4601, AS CONSTRAINED TO CITY OF RENTON SURVEY CONTROL MONUMENT NO. 0057 & 0369. 2.VERTICAL DATUM NAVD 88 PER, AS CONSTRAINED TO CITY OF RENTON CONTROL MONUMENT NO. 0057 ELEVATION = 326.43' - CONTRACTOR TO VERIFY VERTICAL DATUM FROM PROVIDED CONTROL AND SITE FEATURES PRIOR TO CONSTRUCTION. 3.UTILITY NOTE UTILITIES SHOWN HEREON ARE PER KPFF AS-BUILT OF SITE SURFACE FEATURES IN CONJUNCTION WITH UNDERGROUND UTILITY LOCATES PERFORMED BY KPFF. ALL UNDERGROUND UTILITIES SHOULD BE CONSIDERED APPROXIMATE ONLY AND VERIFIED PRIOR TO EXCAVATION. 4.BOUNDARY NOTE AS PER CHICAGO TITLE COMPANY OF WASHINGTON ALTA COMMITMENT FOR TITLE INSURANCE, COMMITMENT NO. 252788-NCS, DATED AUGUST 19, 2025 AND BEST AVAILABLE RECORDS. 5.METHOD OF SURVEY CONTROL SURVEY PERFORMED WITH THE USE OF TOPCON HIPER VR GPS RECEIVERS, TOPOGRAPHIC AND SUPPLEMENTAL CONTROL SURVEY PERFORMED USING CONVENTIONAL GROUND METHODS USING A TOPCON GT SERIES ROBOTIC TOTAL STATION. THE WORK PERFORMED DURING THE COURSE OF THIS SURVEY MEETS OR EXCEEDS THE STANDARDS AS SET FORTH IN WAC 332-130-090. SURVEY WORK PERFORMED IN FEBRUARY 2026. REFUELING AND HAZARDOUS MATERIALS HANDLING GENERAL NOTES: 1.REFUELING OF CONSTRUCTION VEHICLES AND EQUIPMENT ASSOCIATED WITH THIS PROJECT WILL BE LIMITED TO STANDARD CONSTRUCTION ACTIVITIES AND WILL OCCUR IN A CONTROLLED MANNER CONSISTENT WITH MANUFACTURER RECOMMENDATIONS AND APPLICABLE LOCAL, STATE, AND FEDERAL REGULATIONS. ALL ON-SITE REFUELING ACTIVITIES WILL BE PERFORMED IN PRE-DETERMINED DESIGNATED AREAS AWAY FROM STORM DRAINAGE FACILITIES AND AREAS THAT COULD RUNOFF TO OFF-SITE DRAINAGE SYSTEMS OR SURFACE WATERS, WITH APPROPRIATE SPILL PREVENTION MEASURES IN PLACE. 2.HAZARDOUS MATERIALS ANTICIPATED TO BE TEMPORARILY STORED, DISPENSED, USED, OR HANDLED ON-SITE ARE LIMITED TO THOSE COMMONLY ASSOCIATED WITH BUILDING TENANT IMPROVEMENTS, EARTHWORK, UTILITY INSTALLATION, AND PAVEMENT IMPROVEMENTS. THESE MATERIALS MAY INCLUDE, BUT ARE NOT LIMITED TO, FUELS, LUBRICANTS, HYDRAULIC FLUIDS, ASPHALT PRODUCTS, CONCRETE ADDITIVES, SOLVENTS, ADHESIVES, SEALANTS, PAINTS, CURING COMPOUNDS, AND CLEANING AGENTS. MATERIALS WILL BE STORED IN ORIGINAL MANUFACTURER CONTAINERS OR APPROVED SECONDARY CONTAINMENT, LABELED APPROPRIATELY, AND MANAGED TO PREVENT SPILLS, LEAKS, OR UNAUTHORIZED DISCHARGE. 3.CONTRACTORS WILL IMPLEMENT STANDARD BEST MANAGEMENT PRACTICES (BMPS) FOR THE HANDLING, STORAGE, AND DISPOSAL OF HAZARDOUS MATERIALS. IN THE EVENT OF A SPILL, APPROPRIATE RESPONSE MEASURES WILL BE TAKEN IMMEDIATELY TO CONTAIN AND CLEAN UP THE MATERIAL IN ACCORDANCE WITH APPROVED SPILL RESPONSE PROCEDURES. NO LONG-TERM STORAGE OR BULK STORAGE OF HAZARDOUS MATERIALS IS PROPOSED AS PART OF THIS PROJECT. 361 36 0 362 356 35 7 35 8 35 9 36 0 36 1 36 2 36 3 36 4 36 5 36 6 36 3 3 6 4 3 6 5 366 367 368 36 9 370 3 7 1 362 363 364 36 1 36 5 366 35 5 35 6 36 3 36 3 362 36 2 36 0 SSMH RIM = 363.70 IE 10" PVC (S) = 347.86 IE 10" PVC (W) = 347.79 DU M P S T E R PA D SANITARY SEWER MANHOLE STORM DRAINAGE MANHOLE STREET LIGHT POWER VAULT WATER METER WATER VALVE FIRE HYDRANT LIGHT BOX/VAULT TELECOMMUNICATION VAULT DRAINAGE CATCH BASIN IRRIGATION VALVE TELECOMMUNICATION MANHOLE POWER METER LIGHT POLE WATER VAULT FIRE DEPT. CONNECTION VALVE STORM CLEAN OUT GUY ANCHOR PRESSURE INDICATOR VALVE ABANDONED POWER POLE FOUND CASED MONUMENT (AS NOTED) FOUND SURFACE MONUMENT (AS NOTED) FOUND PROPERTY CORNER (AS NOTED) KPFF CONTROL POINT POWER POLE JUNCTION BOX GAS METER GAS VALVE ADA RAMP CONCRETE PAVEMENT EXISTING BUILDING OVERHEAD UTILITY LINE EDGE OF ASPHALT/GRAVEL UNDERGROUND GAS LINE UNDERGROUND WATER LINE UNDERGROUND TELECOMMUNICATION LINE UNDERGROUND POWER CONDUIT STREET SIGN CONCRETE SIDEWALK CONCRETE ASPHALT PAVEMENT DRIVEWAY MAILBOX HANDICAPPED PARKING LANDSCAPED BUSH CONIFER AS NOTED DECIDUOUS AS NOTED ROCKERY KPFF SURVEY CONTROL POINTS POINT # 1 2 3 4 5 6 NORTHING 186684.98 186662.17 186646.08 186448.64 186499.69 186380.73 EASTING 1307905.70 1308174.28 1308319.11 1308181.71 1307985.46 1307894.48 ELEVATION 356.42 364.02 372.05 366.87 361.21 355.91 LEGEND EXISTING MAJOR CONTOUR EXISTING MINOR CONTOUR RIGHT OF WAY LINE CENTER OF RIGHT OF WAY PROPERTY LINE XXX XXX SCALE 0 20 40 DE S I G N E D B Y AP P R O V E D B Y JO B N O : DR A W N B Y CH E C K E D B Y DA T E DRAWING SHEET OF CA L L UN D E R G R O U N D LO C A T E T W O ( 2 ) WO R K I N G D A Y S BE F O R E Y O U DI G 81 1 64 0 W o o d l a n d S q u a r e L o o p , Su i t e 1 0 0 La c e y , W A 9 8 5 0 3 36 0 . 2 9 2 . 7 2 3 0 ww w . k p f f . c o m CH D AP P R BY DA T E NO RE V I S I O N P R O F ESSIONAL E N G I NEER REGI S T E R E D T O S AT E O F WASHIN GT N 5/ 4 / 2 0 2 6 B L A K E A . L O R D 8 SECTION 4, TOWNSHIP 23 NORTH, RANGE 5 EAST, W.M. KING COUNTY , WASHINGTON RE N T O N , W A CUP PERMIT SET 10 1 8 2 6 0 0 0 1 5 KK KK BA L 5/ 4 / 2 0 2 6 CL L MU L T I C A R E R E N T O N O C E D VERTICAL DATUM NAVD 88 BASIS OF BEARING WASHINGTON STATE PLANE COORDINATE SYSTEM, NAD 83/91 NORTH ZONE 4601 3 C2.0 EX I S T I N G C O N D I T I O N S WATER LINE SHOWN PER RECORD WEIGHT LIMIT SIGN TRAFFIC SIGNAL ARM SDMH RIM = 366.67 FOUND BRASS PIN IN CONCRETE INSIDE A MONUMENT CASE AT THE CENTERLINE INTERSECTION OF SUNSET BLVD. & NE 12TH ST. STA 116+07.39 (SR 900) = STA 20+00 (NE 12TH ST). HELD FOUND POSITION FOR ROAD ALIGNMENTS. (VISITED 10/2/2025) CB RIM = 366.34 IE 15" CONC (NE) = 362.83 IE 15" CONC (SW) = 362.57 IE 6" DI (NW) = 362.67 CB RIM = 360.71 IE 12" CPP (SW) = 357.86 POST FOR CROSSWALK BUTTON TRAFFIC SIGNAL POLE SDMH RIM = 360.66 IE 12" CMP (S) = 354.81 RITE-AID SIGN W/ CONC. SUPPORT COLUMNS SDMH RIM = 355.51 IE 18" CMP (N) = 348.56 IE 12" CONC (E) = 351.12 IE 24" CMP (W) = 347.74 SDMH RIM = 355.58 IE 12" CMP (N) = 349.02 IE 24" CMP (E) = 347.74 IE 36" CMP (W) = 347.61 IE 6" CONC (NW) = 351.75 FOUND BRASS PIN IN CONCRETE INSIDE A MONUMENT CASE AT THE CENTERLINE INTERSECTION OF NE 12TH ST. & KIRKLAND AVE. NE. HELD FOUND POSITION FOR ROAD ALIGNMENTS. (VISITED 10/2/2025) SDMH RIM = 354.67 IE 12" CMP (E) = 351.76 IE 18" CMP (S) = 348.81 CB RIM = 354.28 IE 12" CPP (E) = 352.41 IE 12" CPP (NW) = 351.98 2-2" RISERS (W) 2-4" RISERS (W) WATER LINE SHOWN PER RECORD TRANSFORMER (N,S,E) COVERED BUS STOP BUS STOP SIGN CB RIM = 361.71 IE 12" CPP (SW) = 359.89 IE 6" PVC (SE) = 359.89 CB RIM = 363.34 IE 8" PVC (E) = 360.77 IE 12" CPP (W) = 360.49 CONC RETAINING WALLNO PARKING IE 6" PVC = 357.14 GATE TRASH BIN NO PARKING CB RIM = 361.16 IE 12" CPP (NE) = 358.43 IE 12" CPP (SE) = 358.70 DRIVE THRU DELIVERY TUBE NO PARKING CONC RETAINING WALL STORM VAULT DRIVE THRU SIGN 25 MPH CB RIM = 361.22 IE 12" CPP (NE) = 356.06 IE 12" CPP (W) = 356.05 CB RIM = 359.73 IE 12" CPP (E) = 355.31 IE 12" CPP (W) = 355.13 SDMH RIM = 360.36 IE 12" CPP (N) = 354.93 IE 12" CPP (E) = 355.29 COVERED ENTRY SUPPORT COLUMN CONC STEPS RITE-AID SIGN W/ CONC. SUPPORT COLUMNS WATER LINE SHOWN PER RECORD CB RIM = 373.51 IE 15" CONC (SW) = 367.54 COULD NOT REACH PIPES TO THE NORTH & EAST TO OBTAIN INVERT NO TRESPASSING CB RIM = 367.55 IE 6" PVC (E) = 366.08 IE 8" PVC (W) = 365.33 DRIVE THRU SIGN SEPTIC/GREASE TRAP LIDS ASPH SPEED BUMP 6' CHAIN LINK FENCE ROCKERY CB RIM = 364.12 IE 12" CMP (N) = 361.57 NE 12TH ST KI R K L A N D A V E N E HIG H W A Y 9 0 0 / N E S U N S E T B L V D PARCEL NO. 042305-9095 (1.76 AC) 3116 SUNSET BLVD NE RENTON, WA 98056 OWNER: J F INVESTMENTS FF: 362.97' PARCEL NO. 722780-0265 1222 KIRKLAND AVE NE RENTON, WA 98056 OWNER: MEADOW HIGHLANDS LLC PARCEL NO. 722780-0266 3101 NE 13TH ST RENTON, WA 98056 OWNER: SENSET MILES LLC PARCEL NO. 042305-9080 3160 SUNSET BLVD NE RENTON, WA 98056 OWNER: LOUIE FAMILY LLC PROPERTY LINE (TYP) ROW CENTERLINE (TYP) ROW LINE (TYP) GENERAL NOTES: 1.ALL KPFF CONTROL POINTS MAY NOT BE SHOWN IN PLAN VIEW. CONTRACTOR SHALL VERIFY VERTICAL DATUM FROM PROVIDED CONTROL AND SITE FEATURES PRIOR TO CONSTRUCTION. 2.SEE DWG C1.1 FOR KPFF SURVEY GENERAL NOTES. 26 . 7 6 ' 42.16' 3 8 . 5 9 ' 29.08' 37.38' 29.74' 31 . 0 0 ' 37.99' MAI PLACE ASIAN BISTRO EXISTING FIRE HYDRANT EXISTING WATER METER REDUCED PRESSURE BACKFLOW ASSEMBLY SEWER CO RIM = 362.87 IE 6" PVC (S) = 357.36 (APPROX AT BUILDING CONNECTION) 6" PVC SIDE SEWER 1.5" DOMESTIC WATER SERVICE LINE PER RECORD 8" DIP FIRE WATER SERVICE LINE PER RECORD EXISTING RETAINING WALLS EXISTING HANDRAIL BOLTED TO STAIR WALL (TYP) EXISTING 1" IRRIGATION METER AND BACKFLOW ASSEMBLY 365 370 364 366 367 36 8 369 37 1 37 2 37 336 9 368 363 362 36 1 365 37 0 365 356 35 7 35 8 35 9 36 0 36 1 36 2 36 3 36 4 36 5 355 35 5 35 6 36 3 362 362 361 362 36 0 362 362 362 36 3 36 3 36 0 36 0 SCALE 0 20 40 DE S I G N E D B Y AP P R O V E D B Y JO B N O : DR A W N B Y CH E C K E D B Y DA T E DRAWING SHEET OF CA L L UN D E R G R O U N D LO C A T E T W O ( 2 ) WO R K I N G D A Y S BE F O R E Y O U DI G 81 1 64 0 W o o d l a n d S q u a r e L o o p , Su i t e 1 0 0 La c e y , W A 9 8 5 0 3 36 0 . 2 9 2 . 7 2 3 0 ww w . k p f f . c o m CH D AP P R BY DA T E NO RE V I S I O N P R O F ESSIONAL E N G I NEER REGI S T E R E D T O S AT E O F WASHIN GT N 5/ 4 / 2 0 2 6 B L A K E A . L O R D 8 SECTION 4, TOWNSHIP 23 NORTH, RANGE 5 EAST, W.M. KING COUNTY , WASHINGTON RE N T O N , W A CUP PERMIT SET 10 1 8 2 6 0 0 0 1 5 KK KK BA L 5/ 4 / 2 0 2 6 CL L MU L T I C A R E R E N T O N O C E D VERTICAL DATUM NAVD 88 BASIS OF BEARING WASHINGTON STATE PLANE COORDINATE SYSTEM, NAD 83/91 NORTH ZONE 4601 4 C3.0 TE S C & D E M O P L A N LEGEND EXISTING MAJOR CONTOUR EXISTING MINOR CONTOUR RIGHT-OF-WAY PROPERTY LINE SAWCUT LINE DEMOLITION LINE CONSTRUCTION FENCE HIGH VISIBILITY FENCE HIGH VISIBILITY SILT FENCE STRAW WATTLE DISTURBANCE AREA DEMOLITION ITEM INLET SEDIMENT PROTECTION XXX XXX DEMO NOTES: 1.ALL STRUCTURES AND SITE FEATURES WITHIN THE DEMOLITION LIMITS SHALL BE REMOVED UNLESS OTHERWISE NOTED. 2.ALL VEGETATION AND TREES WITHIN THE DEMOLITION LIMITS SHALL BE REMOVED UNLESS OTHERWISE NOTED. 3.ALL EXISTING UNDERGROUND UTILITIES WITHIN THE DEMO AREAS ARE TO BE PRESERVED AND PROTECTED UNLESS OTHERWISE NOTED. 4.ALL EXISTING SURFACE FEATURES AND UTILITIES TO BE PRESERVED AND PROTECTED UNLESS OTHERWISE NOTED. UTILITY NOTE: 1.UTILITIES SHOWN HERE ARE PER KPFF SITE SURVEY OF SURFACE FEATURES, UNDERGROUND LOCATES. ALL UNDERGROUND UTILITIES SHOULD BE CONSIDERED APPROXIMATE ONLY AND SHOULD BE VERIFIED PRIOR TO ANY EXCAVATION. TESC NOTES: 1.CONTRACTOR SHALL PROVIDE CONSTRUCTION FENCING ALONG THE FULL PERIMETER OF THE PROJECT SITE AND ALL LAY DOWN AREAS. 2.TRUCKS SHALL BE MAINTAINED ON ASPHALT OR APPROPRIATE CONSTRUCTION ENTRANCES PROVIDED. 3.CONTRACTOR TO INSTALL STRAW WATTLES, BALE BARRIERS OR OTHER APPROVED PERIMETER PROTECTION MEASURES TO PREVENT SILT-LADEN RUNOFF FROM LEAVING THE SITE. 4.SEE DWG C1.1 FOR TESC GENERAL NOTES. HVF X SF SW INLET SEDIMENT PROTECTION (TYP) PRESERVE & PROTECT EX FIRE WATER LINE (TYP) PRESERVE & PROTECT EX SEWER CLEANOUT AND STUB (TYP) PRESERVE & PROTECT EXISTING WATER METER PRESERVE & PROTECT EXISTING STAIRS (TYP) PRESERVE & PROTECT UNDERGROUND VAULT MAI PLACE ASIAN BISTRO EXISTING BUILDING TO BE IMPROVED (INTERIOR & EXTERIOR). SEE ARCHITECTURAL. PRESERVE & PROTECT POST INDICATOR VALVE PRESERVE & PROTECT FIRE FIRE DEPARTMENT CONNECTION PRESERVE & PROTECT DOUBLE CHECK VALVE ASSEMBLY PRESERVE & PROTECT EXISTING 1.5" WATER SERVICE PRESERVE & PROTECT EXISTING 8" FIRE LINE PRESERVE & PROTECT EXISTING POWER PRESERVE & PROTECT EXISTING POWER PRESERVE & PROTECT EXISTING GAS REMOVE & REPLACE EXISTING TRASH ENCLOSURE REMOVE EXISTING REDUCED PRESSURE BACKFLOW ASSEMBLY AND RECONNECT WATER SERVICE TO EXISTING PRESERVE & PROTECT EXISTING STORM DRAINAGE LINE (TYP) PRESERVE & PROTECT ALL EXISTING LIGHT POLES AND ELECTRICAL SERVICE LINES (TYP) NE S U N S E T B L V D NE 12TH ST NE 13TH ST PRESERVE & PROTECT EXISTING TRASH ENCLOSURE DRAIN SAWCUT (TYP) EXISTING WALLS TO REMAIN (TYP) REMOVE SIDEWALK AS NEEDED FOR IMPROVEMENTS TO MEET ADA ACCESSIBILITY REQUIREMENTS EXISTING TREE TO BE REMOVED PER LANDSCAPE PLANS REMOVE EXISTING DRIVE THRU SIGN14 . 2 ' EXISTING CURB TO REMAIN EXISTING CURB TO REMAIN PRESERVE & PROTECT EXISTING OVERHEAD UTILITY LINES AND POLES (TYP) PRESERVE & PROTECT EXISTING TREES AND VEGETATION (TYP) EXISTING OVERHEAD UTILITIES TO REMAIN (TYP) EXISTING SIGN BASE TO REMAIN EXISTING SIGN BASE TO REMAIN CONTRACTOR TO ENSURE TRACK OUT OR SILT LADEN RUNOFF DOES NOT LEAVE THE SITE. BMPS AND OTHER METHODS MAY BE REQUIRED IF TRACK OUT BECOMES AND ISSUE. ALL DEBRIS TRACKED OFF-SITE SHALL BE REMOVED AND/OR CLEANED AT THE END OF EACH DAY. CONTRACTOR TO ENSURE TRACK OUT OR SILT LADEN RUNOFF DOES NOT LEAVE THE SITE. BMPS AND OTHER METHODS MAY BE REQUIRED IF TRACK OUT BECOMES AND ISSUE. ALL DEBRIS TRACKED OFF-SITE SHALL BE REMOVED AND/OR CLEANED AT THE END OF EACH DAY. PROPERTY LINE (TYP) ROW LINE (TYP) PRESERVE & PROTECT EXISTING 1" IRRIGATION METER AND BACKFLOW ASSEMBLY PRESERVE & PROTECT EXISTING TRAFFIC AND POWER UTILITIES (TYP) PRESERVE & PROTECT EXISTING JUNCTION/LIGHT BOX (TYP) EXISTING RETAINING WALLS TO REMAIN (TYP) 12 . 5 ' 55 ' 42.6' 36' 6.3' 11 . 6 ' 8. 7 ' 37 . 5 ' 23. 9 ' 48' 10' 45 . 2 ' 26.4' S32 ° 0 6 ' 1 6 . 8 0 " W 248 . 2 9 ' S62° 4 7 ' 2 6 . 1 8 " W 36.02 ' S88° 54' 23.77"E 151.36' N1 ° 0 3 ' 1 4 . 9 9 " E 94 . 4 2 ' S88° 50' 55.00"E 39.97' S0 ° 5 7 ' 5 8 . 0 0 " W 80 . 4 7 ' S88° 46' 16.00"E 149.81'S5 8 ° 1 1 ' 4 7 . 0 0 " E 31. 8 6 ' S1 ° 0 3 ' 1 4 . 9 9 " W 5. 0 0 ' N88° 58' 58.01"W 57.50' N88° 58' 58.01"W 151.80' N1 ° 0 9 ' 3 3 . 1 6 " E 23 7 . 8 7 ' LEGEND RIGHT-OF-WAY PROPERTY LINE CEMENT CONCRETE CURB PAVEMENT MARKING BUILDING PER ARCHITECTURAL CEMENT CONCRETE CONCRETE PAVERS PER LANDSCAPE ARCHITECT ASPHALT PAVEMENT LANDSCAPING PER LANDSCAPING PLANS WHEEL STOP ADA PARKING SYMBOL TRAFFIC DIRECTION ARROW PARKING ANALYSIS: EXISTING STANDARD:59 STALLS (20' X 9') ADA ACCESSIBLE:4 STALLS (20' X 10') TOTAL:63 STALLS PROPOSED STANDARD:56 STALLS (20' X 9') ADA ACCESSIBLE:7 STALLS (20' X 9') TOTAL:63 STALLS REQUIRED NUMBER OF ADA STALLS (10% OF TOTAL): 7 TOTAL (5 STANDARD, 2 VAN ACCESSIBLE) PROVIDED NUMBER OF STALLS: 7 TOTAL (5 STANDARD, 2 VAN ACCESSIBLE) STANDARD ACCESSIBLE LOADING ZONE:20' X 5' VAN ACCESSIBLE LOADING ZONE:20' X 9' DE S I G N E D B Y AP P R O V E D B Y JO B N O : DR A W N B Y CH E C K E D B Y DA T E DRAWING SHEET OF CA L L UN D E R G R O U N D LO C A T E T W O ( 2 ) WO R K I N G D A Y S BE F O R E Y O U DI G 81 1 64 0 W o o d l a n d S q u a r e L o o p , Su i t e 1 0 0 La c e y , W A 9 8 5 0 3 36 0 . 2 9 2 . 7 2 3 0 ww w . k p f f . c o m CH D AP P R BY DA T E NO RE V I S I O N P R O F ESSIONAL E N G I NEER REGI S T E R E D T O S AT E O F WASHIN GT N 5/ 4 / 2 0 2 6 B L A K E A . L O R D 8 SECTION 4, TOWNSHIP 23 NORTH, RANGE 5 EAST, W.M. KING COUNTY , WASHINGTON RE N T O N , W A CUP PERMIT SET 10 1 8 2 6 0 0 0 1 5 KK KK BA L 5/ 4 / 2 0 2 6 CL L MU L T I C A R E R E N T O N O C E D SCALE 0 20 40 VERTICAL DATUM NAVD 88 BASIS OF BEARING WASHINGTON STATE PLANE COORDINATE SYSTEM, NAD 83/91 NORTH ZONE 4601 5 C4.0 SI T E P L A N NE S U N S E T B L V D NE 12TH ST KI R K L A N D A V E N E NE 13TH ST AREAS ANALYSIS: PARCEL/LOT AREA:76,481 SF (± 1.76 AC) NEW & REPLACED PAVEMENT:12,696 SF NEW & REPLACED CONCRETE:4,860 SF TOTAL IMPERVIOUS:17,556 SF* (23% OF LOT) TOTAL NEW & REPLACED EXTRUDED CURB:454 LF NEW & REPLACED LANDSCAPING:2,016 SF *AREA DOES NOT INCLUDE RENOVATION/REPLACEMENT OF EXISTING BUILDING 30' HALF ROW REMOVE AND REPLACE EXISTING CONC ADA WALKWAY AND RAMP 4' TYP 4' R A I S E D SI D E W A L K 58 ' H A L F R O W 9' (TYP)5' (TYP) 20 ' APPROX 674 SF CONCRETE DUMPSTER PAD 25 ' H A L F R O W 8' SIDEWALK (TYP) 5' SIDEWALK (TYP) PROPOSED NEW LANDSCAPING ISLAND PROPOSED LANDSCAPING AREA. REMOVE TWO EXISTING PARKING STALLS PROPOSED ADA PARKING (2 VAN ACCESSIBLE, 5 STANDARD) 7 TOTAL 9' STAFF ENTRANCE/DROP OFF 10' SIDEWALK PROPOSED PARKING ISLAND BUILDING OVERHANG PER ARCHITECTURAL BUILDING COLUMN PER ARCHITECTURAL (TYP) AMBULANCE DROP OFF 24' 24' 24 . 5 ' 24 . 5 ' 20.4' 22 . 8 ' 31 . 4 ' 18' 8.5' 8' 4' 13.5 ' 30 ' H A L F R O W MAI PLACE ASIAN BISTRO EXISTING BUILDING TO BE IMPROVED (INTERIOR & EXTERIOR). SEE ARCHITECTURAL. NEW BUILDING FOOTPRINT AND OVERHAND SHOWN. 24 ' INSTALL HANDRAILS ON EXISTING CONC WALL (TYP) MATCH INTO EXISTING SIDEWALK (TYP) MATCH INTO EXISTING CONC CURB (TYP) MATCH INTO EXISTING PAVEMENT (TYP) 28' 8' (TYP) MONOLITHIC SIDEWALK FLUSH WITH ASPHALT (TYP) MONOLITHIC SIDEWALK FLUSH WITH ASPHALT (TYP) MONOLITHIC SIDEWALK FLUSH WITH ASPHALT (TYP) MATCH INTO EXISTING PAVEMENT (TYP) MATCH INTO EXISTING PAVEMENT (TYP) CONC PAD FOR BIKE RACK ADA RAMPS (TYP) 2. 5 ' 30 ' 25' 23 ' 2. 5 ' 6' BOLLARDS PER LANDSCAPE ARCHITECTURAL (TYP) EXISTING CONC WALLS TO REMAIN (TYP) REMOVE AND REPLACE SIDEWALK AS NEEDED TO MEET ADA ACCESSIBILITY REQUIREMENTS EXISTING ACCESS TO REMAIN EXISTING ACCESS TO REMAIN EXISTING SIGN BASE TO REMAIN. SIGN REVISIONS FORTHCOMING. EXISTING SIGN BASE TO REMAIN. SIGN REVISIONS FORTHCOMING. 24.4' 10' 24.6' TRASH ENCLOSURE PER ARCHITECTURAL 37.5' 12' 5' 15' 21.6' 45 ' 18' 52 . 6 ' PATIENT DROP OFF CONC PAVERS FLUSH WITH ASPHALT (TYP) 28' 1 4 ' 2 8 . 4 ' 3. 5 ' PROPERTY LINE (TYP) ROW LINE (TYP) 4' EXISTING TRAFFIC, POWER, AND LIGHTING UTILITIES TO REMAIN (TYP) EXISTING RETAINING WALLS TO REMAIN (TYP) EXISTING TREES & VEGETATION TO REMAIN (TYP) DE S I G N E D B Y AP P R O V E D B Y JO B N O : DR A W N B Y CH E C K E D B Y DA T E DRAWING SHEET OF CA L L UN D E R G R O U N D LO C A T E T W O ( 2 ) WO R K I N G D A Y S BE F O R E Y O U DI G 81 1 64 0 W o o d l a n d S q u a r e L o o p , Su i t e 1 0 0 La c e y , W A 9 8 5 0 3 36 0 . 2 9 2 . 7 2 3 0 ww w . k p f f . c o m CH D AP P R BY DA T E NO RE V I S I O N P R O F ESSIONAL E N G I NEER REGI S T E R E D T O S AT E O F WASHIN GT N 5/ 4 / 2 0 2 6 B L A K E A . L O R D 8 SECTION 4, TOWNSHIP 23 NORTH, RANGE 5 EAST, W.M. KING COUNTY , WASHINGTON RE N T O N , W A CUP PERMIT SET 10 1 8 2 6 0 0 0 1 5 KK KK BA L 5/ 4 / 2 0 2 6 CL L MU L T I C A R E R E N T O N O C E D SCALE 0 20 40 VERTICAL DATUM NAVD 88 BASIS OF BEARING WASHINGTON STATE PLANE COORDINATE SYSTEM, NAD 83/91 NORTH ZONE 4601 6 C5.0 UT I L I T Y P L A N KI R K L A N D A V E N E EXISTING BUILDING TO BE IMPROVED (INTERIOR & EXTERIOR). SEE ARCHITECTURAL. NEW BUILDING FOOTPRINT AND OVERHANG SHOWN. MAI PLACE ASIAN BISTRO NE S U N S E T B L V D NE 12TH ST NE 13TH ST ADJUST EX SEWER CLEANOUT TO GRADE EX RIM = 362.87 EX 6" PVC IE = 357.36 INSTALL 1.5" WATER SERVICE REDUCED PRESSURE BACKFLOW ASSEMBLY IN MECHANICAL ROOM. SEE MEP. LEGEND RIGHT-OF-WAY PROPERTY LINE EXISTING GAS LINE EXISTING POWER LINE EXISTING SANITARY SEWER LINE EXISTING STORM DRAIN LINE EXISTING TELECOM LINE EXISTING WATER LINE EXISTING GAS METER EXISTING POWER METER EXISTING SEWER CLEANOUT EXISTING STORM DRAIN CATCH BASIN EXISTING STORM DRAIN MANHOLE EXISTING TELECOM MANHOLE EXISTING FDC EXISTING PIV UTILITY CONSTRUCTION NOTES: 1.EXISTING UTILITY CONNECTION TO BUILDING MAY REQUIRE REVISIONS DUE TO INTERIOR IMPROVEMENTS. REVISIONS TO BE DETERMINED AT CONSTRUCTION PERMIT LEVEL DESIGN. 1 1 REMOVE EXISTING REDUCED PRESSURE BACKFLOW ASSEMBLY AND RECONNECT WATER SERVICE TO EXISTING EXISTING 8" FIRE SYSTEM DCVA TO REMAIN EXISTING STORM DRAINAGE VAULT TO REMAIN EXISTING FIRE AND DOMESTIC WATER SERVICE LINE TO REMAIN EXISTING STORM DRAINAGE SYSTEM TO REMAIN (TYP) EXISTING OVERHEAD UTILITIES TO REMAIN (TYP) CONNECT NEW BUILDING ROOF DRAIN SYSTEM TO EXISTING STUB AT BUILDING 1 11 1 1 PROPERTY LINE (TYP) ROW LINE (TYP) EXISTING STORM DRAINAGE SYSTEM TO REMAIN (TYP) EXISTING LIGHT POLES TO REMAIN. FIXTURES TO BE REPLACED (TYP). EXISTING LIGHT POLES TO REMAIN. FIXTURES TO BE REPLACED (TYP). SEE IRRIGATION PLANS FOR IRRIGATION REVISIONS (TYP) SEE IRRIGATION PLANS FOR IRRIGATION REVISIONS (TYP) 1" IRRIGATION METER AND BACKFLOW ASSEMBLY TO REMAIN. SEE IRRIGATION PLANS. EXISTING POWER AND TELECOM UTILITIES TO REMAIN (TYP) EXISTING TRAFFIC, POWER, AND LIGHTING UTILITIES TO REMAIN (TYP) 1 356 35 7 35 8 35 9 36 0 36 1 36 2 36 3 36 4 36 5 36 6 360 361 362 355 35 5 35 6 362 363 3 6 4 36 5 3 6 6 367 36 8 369 370 36 3 36 0 365 37 0 36 5 365 3 6 5 36 6 362 36 2 36 3 36 3 35 5 365 36 6 36 3 36 2 362 36 1 1.7% MAX1. 7 % M A X 1. 7 % M A X 36 2 36 2 361 4% 2 % 1% 2% 2% 2% 2% 4 % 5%4%1% 1 % 2% M A X 3.5% 1% 36236 2 DE S I G N E D B Y AP P R O V E D B Y JO B N O : DR A W N B Y CH E C K E D B Y DA T E DRAWING SHEET OF CA L L UN D E R G R O U N D LO C A T E T W O ( 2 ) WO R K I N G D A Y S BE F O R E Y O U DI G 81 1 64 0 W o o d l a n d S q u a r e L o o p , Su i t e 1 0 0 La c e y , W A 9 8 5 0 3 36 0 . 2 9 2 . 7 2 3 0 ww w . k p f f . c o m CH D AP P R BY DA T E NO RE V I S I O N P R O F ESSIONAL E N G I NEER REGI S T E R E D T O S AT E O F WASHIN GT N 5/ 4 / 2 0 2 6 B L A K E A . L O R D 8 SECTION 4, TOWNSHIP 23 NORTH, RANGE 5 EAST, W.M. KING COUNTY , WASHINGTON RE N T O N , W A CUP PERMIT SET 10 1 8 2 6 0 0 0 1 5 KK KK BA L 5/ 4 / 2 0 2 6 CL L MU L T I C A R E R E N T O N O C E D SCALE 0 20 40 VERTICAL DATUM NAVD 88 BASIS OF BEARING WASHINGTON STATE PLANE COORDINATE SYSTEM, NAD 83/91 NORTH ZONE 4601 7 C6.0 GR A D I N G & D R A I N A G E P L A N LEGEND EXISTING MAJOR CONTOUR EXISTING MINOR CONTOUR PROPOSED MAJOR CONTOUR PROPOSED MINOR CONTOUR GRADE BREAK EXISTING CATCH BASIN EXISTING CLEANOUT XXX XXX NOTES: 1.ALL TOP OF CURB ELEVATIONS SHALL BE 6" ABOVE FLOW LINE ELEVATIONS. UNLESS OTHERWISE NOTED. 2.ADA PARKING AND LOADING AREAS SHALL NOT EXCEED 2% IN ANY DIRECTION 3.ALL RAMPS SHALL NOT EXCEED 2% CROSS SLOPE AND 8.33% RUNNING SLOPE GRADING & DRAINAGE KEY NOTES: 1.8' RAMP AT 7.5% OR LESS. 2.EXISTING SYSTEM TO REMAIN. ALL PROPOSED FINISHED GRADING TO MAINTAIN EXISTING DRAINAGE PATTERNS AND SYSTEMS. 3.WALKWAY AT 2% OR LESS CROSS SLOPE. SEE PLAN FOR AREAS OF ASPHALT FLUSH WITH CURB. 4.ASPHALT FLUSH WITH CURB. EXISTING BUILDING TO BE IMPROVED (INTERIOR & EXTERIOR). SEE ARCHITECTURAL. NEW BUILDING FOOTPRINT AND OVERHANG SHOWN. EXISTING FF: 362.97' MAI PLACE ASIAN BISTRO CONNECT NEW BUILDING ROOF DRAIN SYSTEM TO EXISTING STUB AT BUILDING NE S U N S E T B L V D NE 12TH ST NE 13TH ST RAMPS @ 7.5% LANDINGS @ 2% MAX, ALL DIRECTIONS 1 2 PROPERTY LINE (TYP) ROW LINE (TYP) TRASH ENCLOSURE 2 2 2 2 REMOVE AND REPLACE SIDEWALK AS NEEDED TO MEET ADA ACCESSIBILITY REQUIREMENTS EXISTING WALLS TO REMAIN (TYP) 1 1 MATCH EXISTING PAVEMENT (TYP) MATCH EXISTING (TYP) MATCH EXISTING PAVEMENT (TYP) MATCH EXISTING PAVEMENT (TYP) MATCH EXISTING PAVEMENT (TYP) 2 2 XXX XXX 2 2 3 4 25'4 30 ' 4 23 '4 78'4 30 '4 3 3 3 333 30° 6 0 ° 90 ° 12 0 ° 150° 180° Max Kickout 1.278ft Vehicle Tracking V25.00.2775(20240226) (c) Autodesk, Inc. www.Autodesk.com Title:Pumper Fire TruckNotes: Turn(s) based upon a design speed of 2.00mph. 45 f t M i n R a d i u s (O u t e r W h e e l ) 47.352ftMin Radius(Outer Body) 26.46 7 f t 28.469ftMin Radius(Inner Wheel) 40 4 26 Pumper Fire Truck Overall Length 40.000ft Overall Width 8.167ft Overall Body Height 7.745ft Min Body Ground Clearance 0.656ft Track Width 8.167ft Lock-to-lock time 5.00s Curb to Curb Turning Radius 45.000ft DE S I G N E D B Y AP P R O V E D B Y JO B N O : DR A W N B Y CH E C K E D B Y DA T E DRAWING SHEET OF CA L L UN D E R G R O U N D LO C A T E T W O ( 2 ) WO R K I N G D A Y S BE F O R E Y O U DI G 81 1 64 0 W o o d l a n d S q u a r e L o o p , Su i t e 1 0 0 La c e y , W A 9 8 5 0 3 36 0 . 2 9 2 . 7 2 3 0 ww w . k p f f . c o m CH D AP P R BY DA T E NO RE V I S I O N P R O F ESSIONAL E N G I NEER REGI S T E R E D T O S AT E O F WASHIN GT N 5/ 4 / 2 0 2 6 B L A K E A . L O R D 8 RE N T O N , W A CUP PERMIT SET 10 1 8 2 6 0 0 0 1 5 KK KK BA L 5/ 4 / 2 0 2 6 CL L MU L T I C A R E R E N T O N O C E D SCALE 0 40 80 8 C7.0 VE H I C L E T R A C K I N G SCALE 0 20 40 SCALE 0 40 80 APPENDIX C Geotechnical Engineering Services Report Geotechnical Engineering Services Report Renton Off Campus Emergency Department Renton, Washington for KPFF Consulting Engineers May 5, 2026 1145 Broadway, Suite 300 Tacoma, Washington 98402 253.383.4940 KPFF Consulting Engineers | May 5, 2026 Page i File No. 2868-044-00 Table of Contents 1.0 Introduction and Project Understanding ......................................................................... 1 2.0 Site Conditions ............................................................................................................. 1 2.1 Project Vicinity and Site Limits ..................................................................................................... 1 2.2 Surface Conditions........................................................................................................................ 1 2.3 Literature Review .......................................................................................................................... 2 2.3.1 Geologic Mapping .............................................................................................................. 2 2.3.2 Structural Plan Review ...................................................................................................... 2 2.4 Subsurface Conditions ................................................................................................................. 3 2.4.1 Exploration Program .......................................................................................................... 3 2.4.2 Soil Conditions ................................................................................................................... 3 2.4.3 Groundwater Conditions ................................................................................................... 4 3.0 Conclusion and Recommendations ................................................................................ 4 3.1 Primary Geotechnical Considerations ......................................................................................... 4 3.2 Seismic Desing Considerations .................................................................................................... 5 3.2.1 Seismic Design Parameters .............................................................................................. 5 3.2.2 Liquefaction ....................................................................................................................... 6 3.2.3 Lateral Spread ................................................................................................................... 6 3.2.4 Surface Rupture Potential ................................................................................................ 7 3.3 Site Development and Earthwork ................................................................................................ 7 3.3.1 Clearing Stripping and Demolition .................................................................................... 7 3.3.2 Erosion and Sediment Control .......................................................................................... 7 3.3.3 Temporary Excavation ....................................................................................................... 8 3.3.4 Permanent Slopes ............................................................................................................. 8 3.3.5 Groundwater Handling Considerations ............................................................................ 8 3.3.6 Surface Drainage ............................................................................................................... 9 3.3.7 Subgrade Preparation ....................................................................................................... 9 3.3.8 Subgrade Protection and Wet Weather Considerations ................................................. 9 3.4 Fill Materials ................................................................................................................................ 10 3.4.1 Import Fill Materials ........................................................................................................ 10 3.4.2 Pipe Bedding .................................................................................................................... 10 3.4.3 Trench Backfill ................................................................................................................. 10 3.4.4 Capillary Break Material .................................................................................................. 10 3.4.5 Crushed Surfacing for Pavements and Sidewalks ........................................................ 11 3.4.6 On-Site Soil....................................................................................................................... 11 3.4.7 Fill Placement and Compaction ...................................................................................... 11 3.5 Foundation Support .................................................................................................................... 12 3.5.1 General ............................................................................................................................. 12 3.5.2 Bearing Resistance of Existing Footings ........................................................................ 12 3.5.3 Bearing Surface Preparation, Bearing Resistance and Settlement of New Footings . 13 3.5.4 Lateral Resistance of New and Existing Footings .......................................................... 14 3.5.5 Slab-on-Grade Floors ....................................................................................................... 14 3.5.6 Footing and Below-Slab Drainage .................................................................................. 15 KPFF Consulting Engineers | May 5, 2026 Page ii File No. 2868-044-00 3.6 Below Grade Structures .............................................................................................................. 15 3.6.1 General ............................................................................................................................. 15 3.6.2 Drainage ........................................................................................................................... 17 3.7 Stormwater Infiltration ................................................................................................................ 17 3.7.1 General ............................................................................................................................. 17 3.7.2 Pilot Infiltration Test Results ........................................................................................... 18 3.7.3 Soil Physical and Chemical Suitability for Treatment .................................................... 18 3.7.4 Recommended Desing Infiltration Rate ......................................................................... 19 3.8 Pavement Design ........................................................................................................................ 19 3.8.1 General ............................................................................................................................. 19 3.8.2 Asphalt Concrete Pavement Sections ............................................................................ 20 3.8.3 Portland Cement Concrete Pavement Design ............................................................... 20 4.0 Limitations .................................................................................................................. 21 List of Figures Figure 1. Vicinity Map Figure 2. Site Plan Appendices Appendix A. Subsurface Explorations and Laboratory Testing Figure A-1. Key to Explorations Figure A-2 through A-8. Logs of Explorations Figures A-9 and A-10. Sieve Analysis Results Appendix B. Inflitration Testing Figure B-1. PIT-1 Infiltration Testing Figure B-2. PIT-2 Infiltration Testing Appendix C. Report and Limitations and Guidelines for Use KPFF Consulting Engineers | May 5, 2026 Page 1 File No. 2868-044-00 1.0 Introduction and Project Understanding This report presents the results of our geotechnical engineering services for the MultiCare Renton Off Campus Emergency Department (OCED) project. The project site is located at 3116 NE Sunset Boulevard in Renton, Washington, and as shown in the attached Vicinity Map, Figure 1. Our understanding of the project is based on communications with KPFF, review of the project “Geotechnical Report Requirements” document prepared by PCS Structural and our prior involvement on MultiCare OCED projects in the Puget Sound region. The site is currently developed with a former Rite Aid building which we understand will be retrofitted for use by MultiCare as an OCED. Construction of a new structure is not anticipated; however, we expect that seismic retrofitting of the existing building and modifications to existing foundations or construction of additional foundations may be needed. We understand that improvements to the existing parking lot, drive areas and surrounding landscaping may be included in the project. Stormwater infiltration facilities, if included, will be designed in accordance with the current version of the City of Renton Surface Water Design Manual which references and is based on the King County 2021 Surface Water Design Manual. The purpose of our services is to develop an understanding of soil and groundwater conditions at the site as a basis for providing geotechnical design and construction recommendations to support the proposed development. Our services have been provided in accordance with our signed agreement for this project dated January 13, 2026 and executed on March 26, 2026 2.0 Site Conditions 2.1 PROJECT VICINITY AND SITE LIMITS The project site is shown relative to surrounding physical features in Figure 2. Properties in the vicinity are developed with urban construction, consisting of single- and two-story commercial buildings, multi-story apartment complexes, paved city streets and sidewalks and paved driveway and parking areas. The project site is bounded by a restaurant and residential buildings to the north, NE Sunset Boulevard (State Route 900) to the east, NE 12th Street to south and Kirkland Avenue NE to the west. 2.2 SURFACE CONDITIONS The former Rite Aid Building is located near the center of the site. The area surrounding the building is paved with asphalt concrete. Landscape areas with deciduous trees and bushes line most of the eastern, southern and western perimeters of the site. The site is generally flat with elevations ranging from 364 in the northeast to 360 in the southwest (elevations in this report are referenced to the NAVD88 datum and were determined from survey information provided by KPFF). A landscaped slope, between about 4 and 9 feet high with an approximate 2 horizontal to 1 vertical (2H:1V grade, separates NE Sunset Boulevard from the lower grade of the eastern portion of the parking lot. There are several existing retaining walls that border the site. The locations of the walls are shown in the Site Plan Figure 2. A tiered concrete masonry block retaining wall is located along the western site boundary and separates the site grade from the lower elevation of Kirkland Avenue NE. The wall has two tiers, the bottom tier being about 3 feet tall and the upper tier being about 2 feet tall. The north end of the masonry block wall intersects a cast in place concrete retaining wall in the northwest corner of the site. The cast in KPFF Consulting Engineers | May 5, 2026 Page 2 File No. 2868-044-00 place wall is oriented east-west and runs about 150 feet to the east before intersecting a rockery wall that runs north-south along the western edge of a parking area. The cast in place wall is on the order of 5 feet tall and separates the site grade from the lower elevation residential parcels to the north. The rockery appears to be on the order of a few feet tall, however because this wall appears to be constructed on the adjacent parcel to the west and is not immediately visible from the site, we were not able to assess the height along its full length. 2.3 LITERATURE REVIEW 2.3.1 Geologic Mapping We reviewed published geologic information of the project vicinity, including the Geologic Map of Upper Eocene to Holocene Volcanic and Related Rocks in the Cascade Range, Washington (Smith 1993) and the Geologic Map of Surficial Deposits in the Seattle 30’ x 60’ Quadrangle, Washington (Youn 1993). Based on our review, the site is mapped as Vashon Till (Qvt) and Glacial Deposits (Qg) with Vashon Recessional Outwash (Qvr) mapped nearby. 2.3.2 Plan Review We reviewed the 1998 structural plan set (1998 Structural Plans) for the existing structure at the site. The structural plans show that the existing building is supported by conventional shallow foundations, with some spread footings centered over pile caps with 6 inch diameter pipe piles below them. The structural plans indicate that the building floor slab is 4 inches thick and is reinforced with welded wire. The 1998 Structural Plans indicate that footings were designed assuming an allowable soil bearing pressure between 2,000 and 3,000 pounds per square foot (psf). The capacity of the pipe piles is listed at 12 tons although the plans do not specify if this is an allowable or ultimate capacity. The design allowable passive equivalent fluid density and allowable coefficient of friction values are not listed in the 1998 Structural Plans. The 1998 Structural Plans reference a geotechnical report that was prepared for the original development; however, this report was not made available for our review. Construction documentation from the original development including geotechnical field reports or pile installation records are, to our knowledge, not available or do not exist. The 1998 Structural Plans do not indicate if there were specific compaction requirements below footings or slab on grade, or if structural fill was placed below foundations. The 1998 Structural Plans do not indicate if footing drains were included around the perimeter of the building. We understand that as built Civil Plans for the existing development are not currently available. We expect that the original Civil Plans include details on the design of the retaining walls that surround the site. If as built Civil Plans become available, we should be notified and will review the plans to confirm they are consistent with the discussion and recommendations in this report. 2.3.3 Critical Areas Review We completed a review of published City of Renton Critical Areas maps (accessed via the online City of Renton Maps Viewer at https://maps.rentonwa.gov/Html5viewer/Index.html?viewer=CORMaps) and reviewed the City of Renton’s Critical Areas Regulations presented in Section 4-3-050 of the Renton Municipal Code. Our review of critical areas was specific to Geologically Hazardous Areas. KPFF Consulting Engineers | May 5, 2026 Page 3 File No. 2868-044-00 Published critical areas maps do not indicate that there are landslide hazard areas or high erosion hazard areas at the site or in the immediate site vicinity. Published maps indicate that there may be “regulated slopes” with gradients greater than 25 percent (about 4H:1V) but less than 40 percent (about 2.5H:1V) at the site. Based on our observations while onsite, with the exception of the previously mentioned retaining walls, the only slope area within or abutting the site is the landscaped area along the eastern site boundary. The height of this slope is between 4 and 9 feet, and the gradient of the slope is typically around 2H:1V with occasional areas inclined around 1.5H:1V. This slope does not meet the minimum height requirement to be classified as a steep slope (15 feet) per the Renton Municipal Code, and we did not observe any indications of movement, instability or erosion on the slope. Accordingly, in our opinion no setback buffer or special considerations are necessary for development around this slope. We recommend that the slope not be disturbed or regraded as part of the development unless further assessments are made. 2.4 SUBSURFACE CONDITIONS 2.4.1 Exploration Program We explored subsurface conditions at the site by advancing five borings (B-1 through B-8) to depths ranging from about 16.5 to 41.5 feet below ground surface (bgs) and two test pits (PIT-1 and PIT-2) which extended to about 8.5 feet bgs. Boring B-2 was completed as a monitoring well and a pressure transducer was installed to measure and monitor groundwater levels at the site. Approximate locations of our explorations are shown in Figure 2. Selected samples collected from the borings and test pits were tested in our laboratory to confirm field classifications and to evaluate pertinent engineering properties. A detailed description of our exploration and laboratory testing programs, summary exploration logs and laboratory test results is provided in Appendix A. We conducted two small-scale pilot infiltration tests (PITs) in test pits PIT-1 and PIT-2 at depths of approximately 8.0 feet bgs. The PITs were completed to evaluate the infiltration capacity of the native soils on site. Appendix B contains a description of the PIT testing procedures and test results. 2.4.2 Soil Conditions Our explorations were advanced in areas surfaced with pavement sections consisting of 3 to 4 inches of hot-mix asphalt overlying 4 to 8 inches of base coarse material. Underlying the pavement sections, we observed what we interpret to be Recessional Outwash soils. Recessional Outwash soils were present until the bottom of our explorations, which ranged in depth from 8.5 to 41.5 feet bgs. Observed Recessional Outwash generally consisted of loose to dense sand with variable silt and gravel contents (USCS group symbols, SP, SP-SM and SM). Generally speaking, Recessional Outwash soils in the upper portion of the soil profile contained a higher percentage of silt than those encountered at depth. Soils in the upper portion of the profile were loose to medium dense, and the relative consistency of their Recessional outwash tended to increase with depth. The transition between the upper Recessional Outwash soils (typically containing a higher fines content with relative constancies between loose and medium dense) and the lower Recessional Outwash soils (lower fines content and medium dense to dense) varied but typically occurred between depths of about 10 and 20 feet bgs. KPFF Consulting Engineers | May 5, 2026 Page 4 File No. 2868-044-00 2.4.3 Groundwater Conditions Our understanding of groundwater conditions at the site is based on observations during drilling, and measurements collected from the installed monitoring well. We did not observe groundwater or indications of wet soil during drilling of our borings. Minor seepage was observed in test pit PIT-2 at a depth of 1.5 feet bgs but seepage stopped shortly after it was exposed. We interpret the observed seepage to be isolated and discontinuous and the result of surface water infiltrating into the near surface soil profile. Groundwater measurements were made using a pressure transducer installed in the B-2 monitoring well which was screened between 20 and 30 feet bgs (bottom elevation of about 332 NAVD88). Between April 2 and April 28, 2026, groundwater was not measured within monitoring well. Groundwater monitoring with the pressure transducer is ongoing. Until more groundwater data is obtained at the site, we recommend that a groundwater depth of 40 feet bgs, about Elevation 322, (equal to the depth of the bottom of our deepest boring) be considered for design. In our opinion this is reasonable and conservative considering the conditions observed in our explorations, our understanding of the regional groundwater levels in the project vicinity and our experience. However, groundwater monitoring at the site should continue to confirm this assumption. This is particularly important for design of stormwater infiltration facilities. In the event that groundwater depth at the site is shallower than anticipated, it could impact the design recommendations for infiltration facilities. 3.0 Conclusions and Recommendations 3.1 PRIMARY GEOTECHNICAL CONSIDERATIONS A summary of key geotechnical considerations for the project is provided below and is followed by our detailed recommendations. ■ The soil types and relative consistencies observed within the upper 20 feet of our explorations are consistent with potentially liquefiable soils. However, these soils were not saturated and the limited groundwater data we collected suggests that groundwater at the site is deeper than 40 feet bgs. Accordingly, in our opinion the overall risk of liquefaction occurring at this site is low, however we recommend that additional groundwater data be collected to confirm the design groundwater depth and finalize our liquefaction hazard assessment. ■ Most of the soils observed in our explorations contain a significant percentage of fines and could be difficult or impossible to work with when wet. If earthwork activities will take place during wet weather months, we recommend that the contractor performing the work assume that onsite soils will not be suitable for reuse and that imported, wet weather resilient structural fill materials will be required. We also recommend that the overall project budget include contingencies for exporting site soils and importing structural fill if construction will occur during wet weather months. ■ In our opinion existing footings for the structure should be evaluated using the originally prescribed allowable soil bearing pressures outlined in the 1998 Structural Plans. KPFF Consulting Engineers | May 5, 2026 Page 5 File No. 2868-044-00 ■ In our opinion, new footings can be designed assuming an allowable soil bearing pressure of 2,500 psf provided bearing surfaces are prepared as recommended in this report. This value is recommended to help mitigate the risk of differential settlement between existing and new footings. ■ Based on the results of onsite infiltration testing, in our opinion, stormwater infiltration is feasible at this site. Measured infiltration rates at the site varied between the two completed infiltration tests. We recommend that the lower of the two measured rates be used for design due to the fine grained nature of the onsite soils and the variability observed in our explorations. ■ The original plans detailing the design of existing retaining walls at the site were not available for review at the time of this report. We recommend that the existing retaining walls be evaluated to confirm they are suitable for integration with planned redevelopment and can support proposed traffic loads at the site. 3.2 SEISMIC DESING CONSIDERATIONS 3.2.1 Seismic Design Parameters Seismic design of the proposed improvements will be completed using procedures outlined in ASCE 41-17. For the designated performance objectives outlined in ASCE 41-17, seismic design shall consider the following earthquake levels: ■ BPON (Basic Performance Objective Equivalent to New Building Standards) BSE-1N: Basic Safety Earthquake-1, taken as two-thirds of the BSE-2N at a site. BSE-2N: Basic Safety Earthquake-2, taken as the ground shaking based on the Risk-Targeted Maximum Considered Earthquake (MCER) at a site. ■ BPOE (Basic Performance Objective for Existing Buildings) BSE-1E: Basic Safety Earthquake-1, taken as a seismic hazard with a 20 percent probability of exceedance in 50 years (225-year return period). BSE-2E: Basic Safety Earthquake-2, taken as a seismic hazard with a 5 percent probability of exceedance in 50 years (975-year return period). Per ASCE 41-17, seismic ground motion parameters and response spectra records are determined in accordance with ASCE 7-16. Based on soils encountered in the borings, we recommend the site be classified as Site Class D in accordance with ASCE 7-16. Recommended seismic design parameters for code level seismic design in accordance with ASCE 41-17 are presented in Table 1 below KPFF Consulting Engineers | May 5, 2026 Page 6 File No. 2868-044-00 TABLE 1. RECOMMENDED ASCE 41-17 SEISMIC DESIGN PARAMETERS1 ASCE 41-17 (ASCE 7-16) SEISMIC DESIGN PARAMETER2 RECOMMENDED VALUE1 BSE-1N BSE-2N (MCER) (2,475-YEAR) BSE-1E (225-YEAR) BSE-2E (975-YEAR) Mapped Spectral Response Acceleration at Short Period (0.2 second) (SS) n/a 1.425 g 0.484 g 1.041 g Mapped Spectral Response Acceleration at 1 second Period (S1) n/a 0.488 g 0.15 g 0.351 g Site Amplification Factor at 0.2 second period (Fa) n/a 1.0 1.413 1.084 Site Amplification Factor at 1.0 second period (Fv) n/a 1.812 2.3 1.949 Site Adjusted Spectral Response Acceleration at Short Period (0.2 second) (SXS) 0.95 g 1.425 g 0.684 g 1.128 g Site Adjusted Spectral Response Acceleration at 1 second Period (SX1) 0.589 g 0.884 g 0.345 g 0.683 g Design Spectral Acceleration at 0.2 second period (SDS) n/a 4.371 g n/a n/a Design Spectral Acceleration at 1.0 second period (SD1) n/a 1.628 g n/a n/a Site amplification factor at PGA (FPGA) 0.607 0.607 0.607 0.607 Site Modified Peak Ground Acceleration (PGAM)3 0.668 g 0.668 g 0.668 g 0.2668 Notes: 1 Parameters developed based on Latitude 47.503557° and Longitude -122.178008 ° 2 Parameters developed based on Site Class D, 3 Non-modified peak ground acceleration (PGA) is calculated as 0.4 times the site adjusted short-period response acceleration (SXS) 3.2.2 Liquefaction Liquefaction refers to a condition where vibration or shaking of the ground, usually from earthquake forces, results in development of excess pore pressures and subsequent loss of strength in the affected soil deposit. In general, soils that are susceptible to liquefaction include loose to medium dense “clean” to silty sands below the water table. According to the Washington State Department of Natural Resources (DNR) Interactive Natural Hazards Map, the potential for liquefaction at this site is very low. The soil types and relative consistencies observed within the upper 20 feet of our explorations are consistent with potentially liquefiable soils. However, these soils were not saturated and the limited groundwater data collected since the time our explorations were completed suggest that groundwater at the site is deeper than 40 feet bgs. Accordingly, in our opinion the overall risk of liquefaction occurring at this site is low. However, we recommend that additional groundwater data be collected to confirm the design groundwater depth and finalize the conclusions of our liquefaction hazard assessment. 3.2.3 Lateral Spread Lateral spreading related to seismic activity typically involves lateral displacement of large, surficial blocks of non-liquefied soil when a layer of underlying soil loses strength during seismic shaking. Lateral spreading usually develops in areas where sloping ground or large grade changes (including retaining walls) are present. Based on our understanding of the liquefaction risk at the site, the proposed improvements and the site topography, it is our opinion that the risk of lateral spreading at this site is very low. KPFF Consulting Engineers | May 5, 2026 Page 7 File No. 2868-044-00 3.2.4 Surface Rupture Potential According to the DNR Interactive Natural Hazards Map, the project site is in the vicinity of the Seattle fault zone and approximately 1.1 miles away from Newcastle Hills fault trace. Considering the large distance from the nearest trace, it is unlikely that movement of the fault would result in significant surface rupture at the ground surface. In our opinion the risk for surface fault rupture occurring at this site is low. 3.3 SITE DEVELOPMENT AND EARTHWORK We anticipate that site development and earthwork will include demolition of existing features, excavating for shallow foundations and hardscaping and placing and compacting fill and backfill materials. We expect that site grading and earthwork can be accomplished with conventional earthmoving equipment. The following sections provide specific recommendations for site development and earthwork. 3.3.1 Clearing Stripping and Demolition We recommend that existing pavements and hardscaping be completely removed from areas that will be developed. During removal of these features, disturbance of surficial soils may occur, especially if left exposed to wet conditions. Disturbed soils may require additional remediation during construction and grading. If utilities exist beneath planned structures, they should be removed and backfilled or abandoned in place. While not observed in our explorations, cobbles and boulders could be present in the soils observed at this site. The contractor should be prepared to remove boulders and cobbles if encountered during grading or excavation. Boulders may be removed from the site or used in landscape areas. Voids caused by boulder removal should be backfilled with structural fill. 3.3.2 Erosion and Sediment Control Erosion and sedimentation rates and quantities can be influenced by construction methods, slope length and gradient, amount of soil exposed and/or disturbed, soil type, construction sequencing and weather. Implementing an Erosion and Sedimentation Control Plan will reduce the project impact on erosion-prone areas. The plan should be designed in accordance with applicable city, county and/or state standards. The plan should incorporate basic planning principles, including: ■ Scheduling grading and construction to reduce soil exposure; ■ Re-vegetating or mulching denuded areas; ■ Directing runoff away from exposed soils; ■ Reducing the length and steepness of slopes with exposed soils; ■ Decreasing runoff velocities; ■ Preparing drainage ways and outlets to handle concentrated or increased runoff; ■ Confining sediment to the project site; and ■ Inspecting and maintaining control measures frequently. Some sloughing and raveling of exposed or disturbed soil on slopes should be expected. We recommend that disturbed soil be restored promptly so that surface runoff does not become channeled. KPFF Consulting Engineers | May 5, 2026 Page 8 File No. 2868-044-00 Temporary erosion protection should be used and maintained in areas with exposed or disturbed soils to help reduce erosion and reduce transport of sediment to adjacent areas and receiving waters. Permanent erosion protection should be provided by paving, structure construction or landscape planting. Until the permanent erosion protection is established, and the site is stabilized, site monitoring may be required by qualified personnel to evaluate the effectiveness of the erosion control measures and to repair and/or modify them as appropriate. Provisions for modifications to the erosion control system based on monitoring observations should be included in the Erosion and Sedimentation Control Plan. 3.3.3 Temporary Excavation Excavations deeper than 4 feet must be shored or laid back at a stable slope if workers are required to enter. Shoring and temporary slope inclinations must conform to the provisions of Title 296 Washington Administrative Code (WAC), Part N, “Excavation, Trenching and Shoring.” Regardless of the soil type encountered in the excavation, shoring, trench boxes or sloped sidewalls will be required under Washington Industrial Safety and Health Act (WISHA). The contract documents should specify that the contractor is responsible for selecting excavation and dewatering methods, monitoring the excavations for safety and providing shoring, as required, to protect personnel and structures. We recommend that, for planning purposes, temporary cut slopes be assumed to be inclined no steeper than about 1½ H:1V. This guideline assumes that all surface loads are kept at a minimum distance of at least one-half the depth of the cut away from the top of the slope and that seepage is not present on the slope face. Flatter cut slopes will be necessary where seepage occurs or if surcharge loads are anticipated. Temporary covering with heavy plastic sheeting should be used to protect slopes during periods of wet weather. Ultimately the contractor is responsible for establishing and maintaining safe temporary slopes. 3.3.4 Permanent Slopes We recommend permanent slopes be constructed at a maximum inclination of 2H:1V to limit erosion potential. Where 2H:1V permanent slopes are not feasible, protective facings and/or retaining structures should be considered. To achieve uniform compaction, we recommend that fill slopes be overbuilt slightly and subsequently cut back to expose well-compacted fill. Fill placement on slopes steeper than about 5H:1V should be benched into the slope face. The configuration of benches depends on the equipment being used. Bench excavations should be level and extend into the slope face. Exposed areas should be re-vegetated as soon as practical to reduce the surface erosion and sloughing. Temporary protection should be used until permanent protection is established. 3.3.5 Groundwater Handling Considerations We do not anticipate that the regional groundwater table will be encountered in shallow excavations at the site. We recommend that the contractor performing the work be prepared to encounter perched groundwater seepage in excavations at the site. The interface between relatively more permeable and relatively less permeable materials are likely locations for accumulation of perched groundwater. Groundwater seepage handling needs will typically be lower during the late summer and early fall months. We anticipate that perched groundwater, if encountered, can be handled with sumps, pumps and/or diversion ditches, as necessary. Ultimately, we recommend that the contractor performing the work be made responsible for controlling and collecting groundwater encountered. KPFF Consulting Engineers | May 5, 2026 Page 9 File No. 2868-044-00 3.3.6 Surface Drainage Surface water from roofs, pavements and landscape areas should be collected and controlled. Curbs or other appropriate measures such as sloping pavements, sidewalks and landscape areas should be used to direct surface flow away from buildings, erosion sensitive areas and from behind retaining structures. Roof and catchment drains should not be connected to wall or foundation drains. 3.3.7 Subgrade Preparation Subgrades that will support slab-on-grade floors, pavements and other site features should be thoroughly compacted to a uniformly firm and unyielding condition on completion of stripping/excavation and before placing structural fill. Prepared subgrades should be evaluated, as appropriate, to identify areas of yielding or soft soil. Probing with a steel probe rod or proof-rolling with a heavy piece of wheeled construction equipment are appropriate methods of evaluation. If soft or otherwise unsuitable subgrade areas are revealed during evaluation that cannot be compacted to a stable and uniformly firm condition, we recommend that: 1) the unsuitable soils be scarified (e.g., with a ripper or farmer’s disc), aerated and recompacted, if practical; or 2) the unsuitable soils be removed and replaced with compacted structural fill, as needed. 3.3.8 Subgrade Protection and Wet Weather Considerations The wet weather season generally begins in October and continues through May in Western Washington; however, periods of wet weather can occur during any month of the year. The soils encountered in our explorations contain a significant amount of fines. Soil with high fines content is very sensitive to small changes in moisture and is susceptible to disturbance from construction traffic when wet or if earthwork is performed during wet weather. If wet weather earthwork is unavoidable, we recommend that the following steps be taken. ■ The ground surface in and around the work area should be sloped so that surface water is directed away from the work area. The ground surface should be graded so that areas of ponded water do not develop. Measures should be taken by the contractor to prevent surface water from collecting in excavations and trenches. Measures should be implemented to remove surface water from the work area. ■ Earthwork activities should not take place during periods of heavy precipitation. ■ Slopes with exposed soils should be covered with plastic sheeting. ■ The contractor should take necessary measures to prevent on-site soils and other soils to be used as fill from becoming wet or unstable. These measures may include the use of plastic sheeting and controlling surface water with ditches, sumps with pumps and by grading. The site soils should not be left uncompacted and exposed to moisture. Sealing the exposed soils by rolling with a smooth-drum roller prior to periods of precipitation will help reduce the extent to which these soils become wet or unstable. ■ Construction traffic should be restricted to specific areas of the site, preferably areas that are surfaced with working pad materials not susceptible to wet weather disturbance. ■ Construction activities should be scheduled so that the length of time that soils are left exposed to moisture is reduced to the extent practical. KPFF Consulting Engineers | May 5, 2026 Page 10 File No. 2868-044-00 ■ During periods of wet weather, concrete should be placed as soon as practical after preparation of the footing excavations. Foundation bearing surfaces should not be exposed to standing water. If water pools in the base of the excavation, it should be removed before placing structural fill or reinforcing steel. ■ If footing excavations are exposed to extended wet weather conditions, a lean concrete mat or a layer of clean crushed rock can be considered for foundation bearing surface protection. 3.4 FILL MATERIALS 3.4.1 Import Fill Materials The workability of material for use as structural fill will depend on the gradation and moisture content of the soil. Material used for structural fill should be free of debris, organic matter and rock fragments larger than 6 inches. For most applications, we recommend that structural fill material consist of material similar to “Select Borrow” or “Gravel Borrow” as described in Section 9-03.14 of the Washington State Department of Transportation (WSDOT) Standard Specifications. Weather, material use, schedule, duration exposed and site conditions should be considered when determining the type of import fill materials purchased and brought to the site for use as structural fill. Structural fill used during periods of wet weather should consist of material similar to WSDOT Specification 9-03.9 (Aggregates for Ballast and Crushed Surfacing), 9-03.10 (Aggregate for Gravel Base), or 9-03.14 (Borrow) provided that the fines content is less than 5 percent (based on the minus ¾-inch fraction) and the maximum particle size is 6 inches. If prolonged dry weather prevails during the earthwork phase of construction, materials with a somewhat higher fines content may be acceptable. 3.4.2 Pipe Bedding Trench backfill for the bedding and pipe zone should consist of well-graded granular material similar to “gravel backfill for pipe zone bedding” described in Section 9-03.12(3) of the WSDOT Standard Specifications. The material must be free of roots, debris, organic matter and other deleterious material. Other materials may be appropriate depending on manufacturer specifications and/or local jurisdiction requirements. 3.4.3 Trench Backfill Trench backfill must be free of debris, organic matter and rock fragments larger than 6 inches. We recommend that import trench backfill material consist of material similar to “Select Borrow” or “Gravel Borrow” as described in Section 9-03.14 of the WSDOT Standard Specifications. Where water is present, alternative materials may need to be considered. 3.4.4 Capillary Break Material Structural fill placed as capillary break material below on-grade floor slabs should consist of ¾-inch coarse aggregate with negligible sand or silt as described in Section 9-03.1(4)C Grading No. 67 of the WSDOT Standard Specifications. WSDOT Specification 9-03.9 (Aggregates for Ballast and Crushed Surfacing, Crushed Surfacing Base Course [CSBC]) may also be considered). KPFF Consulting Engineers | May 5, 2026 Page 11 File No. 2868-044-00 3.4.5 Crushed Surfacing for Pavements and Sidewalks Structural fill placed as CSBC below pavements and sidewalks should meet the requirements for Crushed Surfacing Base Course, Section 9-03.9(3) of the WSDOT Standard Specifications. 3.4.6 On-Site Soil Based on conditions observed in our subsurface explorations and experience, it is our opinion that existing site soils may be considered for use as structural fill and trench backfill, provided they can be adequately moisture conditioned, placed and compacted as recommended and do not contain organic or other deleterious material. Recessional Outwash soils at the site contain significant amounts of silt and clay sized particles and are extremely moisture sensitive. These soils will be difficult or impossible to properly compact when wet and we do not recommend they be reused as structural fill during periods of wet weather. It is possible that existing soils will be excavated at moisture contents above what is optimum for compaction. In this case, the soils would need to be moisture conditioned (dried) prior to re-use. Space for drying out material during dryer weather or covering on-site materials generated during wet weather should be considered. During wetter or even slightly colder times of year, such as when temperatures get below about 60 degrees, effectively drying out soils is very difficult and often is not possible. In these cases, it should be assumed that over optimum soils would need to be exported from the site and imported structural fill should be used. It is our opinion that if earthwork activities will take place during wet weather months, the contractor performing the work should assume that onsite soils will not be suitable for reuse and that imported, wet weather resilient structural fill materials will be required for earthwork activities. We recommend that the overall project budget include contingencies for exporting site soils and importing structural fill if construction will occur during wet weather months. 3.4.7 Fill Placement and Compaction To obtain proper compaction, fill soil should be compacted near optimum moisture content and in uniform horizontal lifts. Lift thickness and compaction procedures will depend on the moisture content and gradation characteristics of the soil and the type of equipment used. The maximum allowable moisture content varies with the soil gradation and should be evaluated during construction. Generally, 12-inch loose lifts are appropriate for steel-drum vibratory roller compaction equipment. Compaction should be achieved by mechanical means. During fill and backfill placement, sufficient testing of in-place density should be conducted by a representative of GeoEngineers to check that adequate compaction is being achieved. 3.4.7.1 AREA FILLS AND PAVEMENT BASES Fill placed to raise site grades and materials under pavements and structural areas should be placed on subgrades prepared as previously recommended. Fill material placed below structures and footings should be compacted to at least 95 percent of the theoretical maximum dry density (MDD) per ASTM International (ASTM) D 1557. Fill material placed shallower than 2 feet below pavement sections should be compacted to at least 95 percent of the MDD. Fill placed deeper than 2 feet below pavement sections should be compacted to at least 90 percent of the MDD. Fill material placed in landscaping areas should be compacted to a firm condition that will support construction equipment, as necessary, typically around 85 to 90 percent of the MDD. KPFF Consulting Engineers | May 5, 2026 Page 12 File No. 2868-044-00 3.4.7.2 BACKFILL BEHIND BELOW-GRADE STRUCTURES Backfill directly behind retaining walls or below-grade structures should be compacted to between 90 and 92 percent of the MDD. Overcompaction of fill placed directly behind below-grade structures should be avoided. We recommend use of hand-operated compaction equipment and maximum 6 inch loose lift thickness when compacting fill within about 5 feet behind below-grade structures. 3.4.7.3 TRENCH BACKFILL For utility excavations, we recommend that the initial lift of fill over the pipe be thick enough to reduce the potential for damage during compaction but generally should not be greater than about 18 inches above the pipe. In addition, rock fragments greater than about 1 inch in maximum dimension should be excluded from this lift. Trench backfill material placed below structures and footings should be compacted to at least 95 percent of the MDD. In paved areas, trench backfill should be uniformly compacted in horizontal lifts to at least 95 percent of the MDD in the upper 2 feet below subgrade. Fill placed below a depth of 2 feet from subgrade in paved areas must be compacted to at least 90 percent of the MDD. In non-structural areas, trench backfill should be compacted to a firm condition that will support construction equipment, as necessary. 3.5 FOUNDATION SUPPORT 3.5.1 General In our opinion shallow foundations are appropriate for supporting improvements at this site. We expect that shallow foundations will be constructed to support new improvements and as part of the existing building retrofit. Additionally, we anticipate that the existing footings for the building will be evaluated by the structural engineer as part of the building retrofit. The sections below provide recommendations for design and construction of new shallow foundations and for evaluating the existing building footings. Exterior footings should be established at least 18 inches below the lowest adjacent grade. Interior footings can be founded a minimum of 12 inches below the top of the floor slab. Isolated column and continuous wall footings should have minimum widths of 24 and 18 inches, respectively. The recommended allowable bearing pressures provided below apply to the total of dead and long-term live loads and may be increased by one-third when considering total loads, including earthquake or wind loads. These are net bearing pressures. The weight of the footing and overlying backfill can be ignored in calculating footing sizes. 3.5.2 Bearing Resistance of Existing Footings Based on our interpretation of the boring logs, the existing footings at the site are likely supported on Recessional Outwash. The near surface existing Recessional Outwash soils observed in our borings was typically loose to medium dense. It is unclear what, if any, procedures were followed to compact bearing surfaces below the existing structure foundations. If records of fill placement or bearing surface preparation are available, they should be provided to us for review. KPFF Consulting Engineers | May 5, 2026 Page 13 File No. 2868-044-00 The 1998 Structural Plans indicate that the existing structure was designed using an allowable bearing resistance of 3,000 psf. The plans also indicate that select footings, primarily those along the east exterior walls included 6 inch diameter steel pipe piles below them. The capacity of the pipe piles is listed at 12 tons although the plans do not specify if this is an allowable or ultimate capacity or if the value is associated with uplift or downward axial resistance. It is unclear on the reviewed plans why pipe piles were included below some footings. It is also our understanding that records of pile installation are not available, and it is unclear if the target capacities of the piles were verified during installation. Based on the conditions observed in our explorations, we recommend that existing footings for the building retrofit be evaluated using the same allowable soil being pressure as considered for the original design (3,000 psf). In our opinion, it may be prudent to neglect or consider a reduced allowable resistance provided by the steel pipe piles. At a minimum, if the resistance provided by the steel pipe piles is being considered for design, we recommend that additional information regarding the design and construction of the piles be obtained. 3.5.3 Bearing Surface Preparation, Bearing Resistance and Settlement of New Footings New footings can bear directly on compacted Recessional Outwash soils or structural fill extending to these soils. We recommend that the base of all footing excavations be proof compacted to a uniformly firm and unyielding condition prior to placement of structural fill, formwork or rebar. If soft or otherwise unsuitable areas are observed at the base of the overexcavation that cannot be compacted to a stable and uniformly firm condition the following options may be considered: 1) the exposed soils be moisture conditioned and recompacted; or 2) the unsuitable soils be overexcavated to expose competent soils and the overexcavation be backfilled with compacted structural fill. All structural fill placed below footings must be compacted to 95 percent of the MDD. It may also be acceptable to overpour the footings opposed to backfilling overexcavations with structural fill; however, this practice should be approved by the structural engineer during construction. We expect that overexcavation depths can be limited to 24 inches below design bottom of footing elevation. If organic-rich soil or other deleterious material is encountered below footings, we recommend complete removal of these materials so greater overexcavation depths could be necessary. Foundation bearing surfaces should not be exposed to standing water. If water is present in the excavation, it must be removed before placing structural fill, formwork and reinforcing steel. Protection of exposed soil should be considered during the wetter times of the year. The amount of protection will depend, in part, on prevailing weather, soil type exposed and duration exposed. Typically, a 3- to 4-inch lean concrete mat or a 6- to 8-inch crushed rock section is suitable for foundation bearing surface protection. Prepared foundation bearing surfaces should be observed and evaluated by a member of our firm prior to placement of structural fill, formwork or steel reinforcement. Our representative will confirm that the bearing surfaces have been prepared in accordance with our recommendations and are suitable for supporting the design footing load and provide recommendations for remediation, if necessary. KPFF Consulting Engineers | May 5, 2026 Page 14 File No. 2868-044-00 New shallow foundations bearing on structural fill or proof compacted Recessional Outwash may be designed using an allowable soil bearing pressure of 2,500 psf. The recommended design bearing resistance for new foundations is less than what was used for design of the original building. In our opinion, this is prudent to limit the potential for differential settlement between existing and new foundations, to reduce the risk of loads from new footings inducing settlement of soils below existing foundations and because there will be limited options for remediating or improving soils below new foundations that will be constructed through the existing building slab. Provided bearing surfaces are prepared as recommended, we estimate the total static settlement of shallow foundations will be on the order of 1 inch or less for the bearing pressures presented above. Differential settlements could be on the order of ½ inch between comparably loaded isolated column footings or along 50 feet of continuous footing. Settlement is expected to occur rapidly as loads are applied. Settlements could be greater than estimated if loose or disturbed soil is present beneath footings. 3.5.4 Lateral Resistance of New and Existing Footings The ability of the soil to resist lateral loads is a function of frictional resistance, which can develop on the base of footings and slabs and the passive resistance, which can develop on the face of below-grade elements of the structure as these elements tend to move into the soil. The allowable frictional resistance on the base of the footing may be computed using a coefficient of friction of 0.40 applied to the vertical dead-load forces. The allowable passive resistance on the face of the footing or other embedded foundation elements may be computed using an equivalent fluid density of 275 pounds per cubic foot (pcf) for undisturbed site soils or structural fill extending out from the face of the foundation element a distance at least equal to two and one-half times the depth of the element. These values include a factor of safety of about 1.5. The design allowable passive equivalent fluid density and allowable coefficient of friction values are not listed in1998 Structural Plans. In our opinion the lateral resistance design parameters provided above can also be used for evaluating the existing foundations. The passive earth pressure and friction components may be combined provided that the passive component does not exceed two-thirds of the total. The passive earth pressure value is based on the assumptions that the adjacent grade is level, and that groundwater remains below the base of the footing throughout the year. The top foot of soil should be neglected when calculating passive lateral earth pressure unless the area adjacent to the foundation is covered with pavement or a slab-on-grade. 3.5.5 Slab-on-Grade Floors We anticipate that the existing building slab on grade will be reused. However, portions of the slab on grade will likely be replaced or reconstructed as a result of new utility and footing installation within the building. Bearing surfaces for slab on grade floors should be prepared in accordance with Section “3.3.7 Subgrade Preparation” of this report. Slab on grade floors can be supported on existing site soils. The exposed subgrade should be evaluated after site grading is completed by a member of our firm. Disturbed areas should be compacted, if possible, or removed and replaced with compacted structural fill. KPFF Consulting Engineers | May 5, 2026 Page 15 File No. 2868-044-00 We recommend slab-on-grade floors be underlain by a minimum 6-inch-thick capillary break consisting of material similar to what is recommended in Section “3.4.4 Capillary Break Material”. The presence and condition of capillary break material below the existing building slab on grade has not been confirmed. We expect that it will not be practical to replace or install a capillary break section below the existing slab as part of construction. We recommend that portions of the capillary break section exposed during construction be observed and evaluated by a member from our firm. If during construction, areas of damp or wet slabs are observed, it could be necessary to remove the existing slab and replace the capillary break section in those areas. Provided that loose soil is removed, and the subgrade is prepared as recommended, we recommend slabs- on-grade be designed using a modulus of subgrade reaction of 250 pounds per cubic inch (pci). We estimate that settlement for slabs-on-grade constructed as recommended will be less than ¾ inch for a floor load of 500 psf. 3.5.6 Footing and Below-Slab Drainage It is unclear if the existing building has a perimeter or underslab drainage system. Based on the conditions observed in our explorations, in our opinion a foundation or below-slab drainage system is not necessary to maintain structural support. However, a perimeter foundation drainage system will help maintain dry conditions below the building and should be considered by the project team from a building serviceability and maintenance perspective. Foundation drains should be designed to collect and direct water away from the perimeter of the building. The drains should be provided with cleanouts and should consist of at least 4-inch-diameter perforated pipe. The pipe should be placed on a 3-inch bed of, and surrounded by, 6 inches of drainage material. A nonwoven geotextile fabric should be placed between the drain rock and existing site soils to prevent fine soil from migrating into the drain material. We recommend that the drainpipe consist of either heavy-wall solid pipe or rigid corrugated smooth interior polyethylene pipe. We do not recommend using flexible tubing for footing drainpipes. The drain material should consist of pea gravel or material similar to “Gravel Backfill for Drains” per Washington State Department of Transportation (WSDOT) Standard Specifications Section 9-03.12(4). The drains should be sloped to drain by gravity, if practical, to a suitable discharge point. Water collected in roof downspout lines must not be routed to the perimeter footing drains. If an existing drainage system is present, we recommend that existing systems around the building be inspected during construction. The inspection should confirm that the drains are intact and have not become plugged or otherwise compromised. We also recommend that the existing drainage system, if present, be reviewed by the project Civil Engineer to verify that the existing system has adequate capacity for the currently envisioned improvements. We recommend that damaged portions of drainage systems be repaired or replaced, as necessary. 3.6 RETAINING WALLS AND BELOW GRADE STRUCTURES 3.6.1 Existing Retaining Walls As described previously, there are several existing retaining walls at the site and existing plans or design information pertaining to the walls were not available for review. We were not able to make a detailed visual assessment of these walls while we were onsite for our field activities as they were either overgrown with vegetation (portions of the concrete masonry block retaining wall) or were not fully visible from the parcel and access permissions to inspect the walls from adjacent parcels had not been coordinated (cast in place wall and rockery). However, during our site reconnaissance activities we did not observe any obvious signs of wall distress or failure. KPFF Consulting Engineers | May 5, 2026 Page 16 File No. 2868-044-00 We recommend that the internal stability of the existing walls at the site be evaluated to confirm that they are suitable for continued use. This should include a structural evaluation using the lateral soil earth pressures provided below (unless the earth pressures that were originally used for design of the walls are found and confirmed to be appropriate for continued use) as well as the seismic and traffic surcharge loads discussed below. We also recommend that the drainage system associated with the cast in place wall be further investigated to confirm if it is functional and suitable for continued use. If a drainage system is not present or is not functioning properly, it should be confirmed that the cast in place retaining wall can resist pressures associated with undrained soil conditions, or the drainage system should be repaired/replaced. We completed limit equilibrium slope stability analyses to assess the global stability of the existing concrete masonry block retaining wall and cast in place retaining walls. Since full details regarding wall design and construction were not available for our review, our slope stability models reflected conservative assumptions with regards to soil conditions behind the walls and wall dimensions that have an impact on global stability (e.g. foundation embedment depth). Our slope stability analyses results indicate that the existing masonry block retaining wall and cast in place retaining wall meet minimum factory of safety requirements outlined in the Washington State Department of Transportation Geotechnical Design Manual for global slope stability considering static and pseudo static conditions, 1.5 and 1.1, respectively. If the as-built plans or additional design information regarding the existing retaining walls at the site are obtained, they should be provided for our review and we will complete updated global slope stability assessments, if necessary. 3.6.2 General We recommend the following lateral earth pressures be used for design of conventional retaining walls and below-grade structures. Our design pressures assume that the ground surface around the retaining structures will be level or near level. If drained design parameters are used, drainage systems must be included in the design in accordance with the recommendations presented in Section 3.6.3 below. ■ Active soil pressure may be estimated using an equivalent fluid density of 35 pcf for the drained condition. ■ Active soil pressure may be estimated using an equivalent fluid density of 80 pcf for the undrained condition; this value includes hydrostatic pressures. ■ At-rest soil pressure may be estimated using an equivalent fluid density of 56 pcf for the drained condition ■ At-rest soil pressure may be estimated using an equivalent fluid density of 88 pcf for the undrained condition; this value includes hydrostatic pressures. ■ For seismic considerations, a uniform lateral pressure of 16H psf (where H is the depth of a structure bgs) should be added to the lateral earth pressure. ■ A typical traffic surcharge of 250 psf should be included if vehicles are allowed to operate within ½ the height of the retaining walls. Other surcharge loads should be considered on a case-by-case basis. We can provide additional surcharge loads for specific loading conditions once known. KPFF Consulting Engineers | May 5, 2026 Page 17 File No. 2868-044-00 The active soil pressure condition assumes the wall is free to move laterally 0.001H, (where H is the wall height). The at-rest condition is applicable where walls are restrained from movement. The above- recommended lateral soil pressures do not include other surcharge loads than described, or the effects of sloping backfill surfaces. We should be consulted if other surcharge loads are anticipated or if sloping backfill conditions are planned, this may change the lateral pressure values provided. Overcompaction of fill placed directly behind below-grade structures must be avoided. We recommend use of hand-operated compaction equipment and maximum 6-inch loose lift thickness when compacting fill within about 5 feet of retaining walls and below-grade structures. Below grade structure bearing surfaces should be prepared following Section 3.5.3 of this report. Provided bearing surfaces are prepared as recommended, below grade structures may be designed using the allowable soil bearing values and lateral resistance values presented above. We estimate settlement of below grade structures will be similar to the values previously presented for spread foundations. 3.6.3 Drainage If below-grade structures are designed using drained parameters, a drainage system behind the structure must be constructed to collect water and prevent the buildup of hydrostatic pressure against the structure. We recommend the drainage system includes a zone of free-draining backfill a minimum of 18 inches in width against the back of the wall. The drainage material should consist of coarse sand and gravel containing less that 5 percent fines based on the fraction of material passing the ¾-inch sieve. Material similar to “Gravel Backfill for Drains” per WSDOT Standard Specifications Section 9-03.12(4) is also suitable. Waffle board-type drainage mats may be considered instead of gravel, provided they are protected from accumulating silt and discharge appropriately. A perforated, rigid, smooth-walled drainpipe with a minimum diameter of 4 inches should be placed along the base of the structure within the free-draining backfill and extend for the entire wall length. The drain pipe should be metal or rigid polyvinyl chloride (PVC) pipe and be sloped to drain by gravity. Discharge should be routed to appropriate discharge areas and designed to reduce erosion potential. Cleanouts should be provided to allow routine maintenance. We recommend roof downspouts or other types of drainage systems not be connected to retaining wall drain systems. We recommend GeoEngineers be retained to review the retaining wall design calculations and plans to confirm design meets the recommendations provided in this report. 3.7 STORMWATER INFILTRATION 3.7.1 General We understand that the design of the proposed infiltration management facility has not been finalized and will, in part, be informed by the results of infiltration testing herein. Preliminary plans to manage stormwater at the site include below-grade infiltration facilities such as StormTech chambers. We understand that the infiltration facility will be designed according to the City of Renton Surface Water Design Manual which references and is based on the King County 2021 Surface Water Design Manual (2021 KCSWDM). Two PITs were completed at the site to evaluate stormwater infiltration potential. Both PITs were completed within Recessional Outwash soils at depths of around 8 feet below existing site grades. The target testing depth for our PITs was selected in coordination with KPFF. KPFF Consulting Engineers | May 5, 2026 Page 18 File No. 2868-044-00 Based on the subsurface conditions observed in our explorations and the results of our onsite infiltration testing, it is our opinion that stormwater infiltration into the native Recessional Outwash soils at the site is feasible. The sections below provide recommendations for preliminary design of infiltration facilities. Appendix B includes a detailed description of the infiltration testing procedures and results. 3.7.2 Pilot Infiltration Test Results Table 2 summarizes the measured infiltration rates determined from the PITs. TABLE 2: STORMWATER INFILTRATION RATE TESTING RESULTS TEST LOCATION SOIL TYPE AT TEST DEPTH ELEVATION OF INFILTRATION TEST (FEET, NAVD88) MEASURED INFILTRATION RATE (IN/HR) PIT-1 Recessional Outwash (SM, 25 percent fines) 354 3.3 PIT-2 Recessional Outwash (SM, 21 percent fines) 353 1 Notes: in/hr = inches per hour 1 Elevations are based on survey by KPFF, dated February 2026 and should be considered approximate 3.7.3 Soil Physical and Chemical Suitability for Treatment According to the 2021 KCSWDM, for infiltration facilities that intend to use the native soil to provide runoff treatment: ■ The CEC of the treatment soil must be greater than or equal to 5 milliequivalents per 100 grams of soil (meq/100g), ■ An organic content of 1.0 percent or greater is necessary, and ■ Waste fill materials shall not be used as infiltration soil media. The Table below summarizes the results of the CEC testing conducted on samples taken from the bottom of each of our PIT locations: TABLE 3. RESULTS OF ORGANIC CONTENT AND CATION EXCHANGE CAPACITY TESTING LOCATION SAMPLE DEPTH (FEET BGS) ORGANIC CONTENT (%) CATION EXCHANGE CAPACITY, CEC (MEQ/100G) PIT-1 8.5 0.9 4.6 PIT-2 8.5 2.2 7.9 Notes: feet bgs = feet below ground surface % = percent by weight of organic matter in the soil meq/100g = milliequivalents per 100 grams of soil KPFF Consulting Engineers | May 5, 2026 Page 19 File No. 2868-044-00 3.7.4 Recommended Desing Infiltration Rate Based on the results of onsite infiltration testing, in our opinion stormwater infiltration is feasible at this site. Measured infiltration rates at the site varied between the two completed infiltration tests. We recommend that the lower of the two measured rates (1 inch per hour) be used to establish the design infiltration rate due to the fine-grained nature of the onsite soils and the variability observed in our explorations. The design infiltration rate is determined by applying correction factors to the infiltration rate measured during testing. The correction factors account for uncertainties in testing, depth to the water table or impervious strata, infiltration facility geometry and long-term reductions in permeability due to biological activity and accumulation of fines. As described in Appendix B we currently recommend that a total correction factor of 0.35 be used to determine the design infiltration rate. This total correction factor assumes that the geometry factor will be equal to 1.0, which could change based on the final facility geometry. Based on the recommended infiltration rate determined during field testing (1 inch per hour) and the currently recommended total correction factor (0.35), we recommend that infiltration facilities be evaluated considering a preliminary design infiltration rate of 0.35 inches per hour. Once the final facility dimensions are known and additional groundwater data is collected, the geometry factor should be recalculated using the equation in Appendix B and applied so a final design infiltration rate can be determined. The final infiltration rate used for design of facilities should be reviewed and confirmed by GeoEngineers. 3.8 PAVEMENT DESIGN 3.8.1 General New paving areas are expected to include improvements to the parking areas, driveways and sidewalks. We provide recommended conventional asphalt concrete pavement (ACP) and Portland cement concrete (PCC) sections below. These sections are based on our experience as no specific traffic loading was available at the time of our report. Standard duty pavement sections are intended for automobile parking. Heavy duty pavement sections are intended for occasional heavy truck use such as the route used by garbage trucks. These pavement sections may not be adequate for heavy construction traffic loads such as those imposed by concrete transit mixers, dump trucks or cranes. Additional pavement thickness may be necessary to prevent pavement damage during construction if other loading types are planned. The recommended sections assume that final improvements surrounding the pavements will be designed and constructed such that stormwater or excess irrigation water from landscape areas does not accumulate below the pavement section or pond on pavement surfaces. Existing pavements, hardscaping or other structural elements should be removed prior to placement of new pavement sections. Pavement subgrade should be prepared as recommended in Section 3.3.7 of this report. Crushed surfacing base course and subbase should be moisture conditioned to near optimum moisture content and compacted to at least 95 percent of the theoretical MDD per ASTM D 1557. KPFF Consulting Engineers | May 5, 2026 Page 20 File No. 2868-044-00 CSBC and crushed surfacing top course (CSTC) should conform to applicable sections of 4-04 and 9-03.9(3) of the WSDOT Standard Specifications. The top approximate 2 inches of the CSBC sections provided may consist of CSTC as a leveling layer and for more precise grade development. Hot mix asphalt should conform to applicable sections of 5-04, 9-02 and 9-03 of the WSDOT Standard Specifications. PCC mix design should conform with Section 5-05.3(1) of the WSDOT Standard Specifications. Aggregates for PCC should conform to applicable sections of 9-03.1 of the WSDOT Standard Specifications. Some areas of pavement may exhibit settlement and subsequent cracking over time. Cracks in the pavement will allow water to infiltrate to the underlying base course, which could increase the amount of pavement damage caused by traffic loads. To prolong the effective life of the pavement, cracks should be sealed as soon as possible. 3.8.2 Asphalt Concrete Pavement Sections Recommended minimum ACP sections are provided below. 3.8.2.1 STANDARD-DUTY – AUTOMOBILE DRIVEWAYS AND PARKING AREAS ■ Two (2) inches of hot mix asphalt, class ½ inch, PG 58-22 ■ Four (4) inches of compacted CSBC ■ Native soil, existing fill or structural fill prepared as recommended in Section 3.3.7 of this report 3.8.2.2 HEAVY DUTY ACP – AREAS SUBJECT TO OCCASIONAL HEAVY TRAFFIC ■ Three (3) inches of hot mix asphalt, class ½ inch, PG 58-22 ■ Six (6) inches of compacted CSBC ■ Native soil, existing fill or structural fill prepared as recommended in Section 3.3.7 of this report 3.8.3 Portland Cement Concrete Pavement Design Recommended minimum PCC pavement sections are provided below. In our opinion steel reinforcement does not need to be included in PCC pavements that will be primarily used in landscaping and pedestrian areas (areas not subjected to heavy vehicle traffic). Reinforcement could be considered to reduce the potential for cracking in areas where the concrete slabs have irregular shapes or where new slabs abut existing concrete slabs, and the joint layout between the slabs cannot be matched. If reinforcement is considered, we are available to discuss typical steel reinforcement volumes with the project structural engineer, who ultimately designs the location, size and layout of reinforcement. 3.8.3.1 SIDEWALK PCC PAVEMENT – PEDESTRIAN AREAS NOT SUBJECTED TO VEHICLE LOADING ■ Four (4) inches of PCC with a minimum 14-day flexural strength of 650 pounds per square inch (psi) ■ Two (2) inches of compacted CSBC ■ Native subgrade or structural fill prepared in accordance with Section 3.3.7 of this report KPFF Consulting Engineers | May 5, 2026 Page 21 File No. 2868-044-00 3.8.3.2 STANDARD PCC PAVEMENT – AUTOMOBILE DRIVEWAYS AND PARKING AREAS ■ Six (6) inches of PCC with a minimum 14-day flexural strength of 650 psi ■ Four (4) inches of compacted CSBC ■ Native subgrade, existing fill or structural fill prepared in accordance with Section 3.3.7 of this report 3.8.3.3 HEAVY DUTY PCC PAVEMENT – AREAS SUBJECT TO OCCASIONAL HEAVY TRAFFIC ■ Nine (9) inches (minimum) of PCC with a minimum 14-day flexural strength of 650 psi ■ Four (4) inches of compacted CSBC ■ Native subgrade, existing fill or structural fill prepared in accordance with Section 3.3.7 of this report 4.0 Limitations We have prepared this report for KPFF Consulting Engineers for the Renton Off Campus Emergency Department project located in Renton, Washington. KPFF Consulting Engineers may distribute copies of this report to owner and owner’s authorized agents and regulatory agencies as may be required for the project. Within the limitations of scope, schedule and budget, our services have been executed in accordance with generally accepted practices for geotechnical engineering in this area at the time this report was prepared. The conclusions, recommendations and opinions presented in this report are based on our professional knowledge, judgment and experience. No warranty, express or implied, applies to the services or this report. Please refer to Appendix C titled “Report Limitations and Guidelines for Use” for additional information pertaining to use of this report. Figures LOT 1 (R2) SUBJECT PARCEL B-1 B-2 B-3 B-4 B-5 PIT-2 PIT-1 Figure 2 Site Plan N N P: \ 2 \ 2 8 6 8 0 4 4 \ C A D \ 0 0 \ G e o t e c h \ 2 8 6 8 0 4 4 0 0 _ F 0 2 _ S i t e P l a n . d w g 2 D a t e E x p o r t e d : 5/ 5 / 2 0 2 6 1 0 : 0 2 A M - b y Ty l e r J . M i c h a u d Renton Off Campus Emergency Department Renton, Washington Legend 40 Source(s): ·Survey by KPFF, dated February 2026. ·Proposed site features from KPFF. Coordinate System: WA State Plane, N Zone, NAD83, US Foot Disclaimer: This figure was created for a specific purpose and project. Any use of this figure for any other project or purpose shall be at the user's sole risk and without liability to GeoEngineers. The locations of features shown may be approximate. GeoEngineers makes no warranty or representation as to the accuracy, completeness, or suitability of the figure, or data contained therein. The file containing this figure is a copy of a master document, the original of which is retained by GeoEngineers and is the official document of record. Feet 0 N Site Boundary B-X Boring by GeoEngineers, 2026 Existing Building PIT-X Pilot Infiltration Test, 2026 NE S u n s e t B o u l e v a r d ( S R 9 0 0 ) NE 12th Street Ki r k l a n d A v e N E Site Boundary Existing Building B-X Monitoring Well by GeoEngineers, 2026 Tie r e d C o n c r e t e M a s o n r y B l o c k R e t a i n i n g W a l l Cast in Place Concrete Retaining Wall Ro c k e r y Appendices Appendix A Subsurface Explorations and Laboratory Testing KPFF Consulting Engineers | May 5, 2026 Page A-1 File No. 2868-044-00 Appendix A Subsurface explorations and Laboratory Testing SUBSURFACE EXPLORATIONS Exploration Program Soil conditions at the project site were explored by advancing five borings (B-1 through B-5) between April 2 and 3, 2026 and two test pits (PIT-1 and PIT-2) on April 16,2026. Approximate locations of our explorations are shown in the Site Plan, Figure 2. The explorations were located in the field using a handheld global positioning system (GPS) device. Locations and elevations of the explorations presented herein should be considered approximate. Boring B-4 was completed as a groundwater monitoring well to observe groundwater conditions at the site. Borings Borings extended to approximate depths between 11.5 and 41.5 feet bgs. Borings were advanced using hollow-stem auger drilling methods and a Diedrich D-70 Turbo track-mounted drill rig provided and operated by Holt Services, Inc. under subcontract to GeoEngineers. Standard Penetration Tests (SPTs) were completed using a 1.4-inch-inner-diameter split-barrel sampler driven into the soil using a 140-pound hammer free-falling a distance of 30 inches. The number of blows required to drive the sampler the last 12 inches, or other indicated distance is recorded on the logs as the blow count. SPTs were advanced at 2.5- to 5-foot intervals. The drilling was continuously monitored by an engineer from our firm who maintained a detailed log of subsurface explorations, visually classified the soil encountered and obtained representative soil samples from the borings. Recovered soil samples were visually classified in the field in general accordance with ASTM International (ASTM) D 2488 and the classification chart listed in Key to Exploration Logs, Figure A-1. The logs of the borings are presented in Figures A-2 through A-6. The log is based on interpretation of the field and laboratory data and indicates the depth at which subsurface materials, or their characteristics, change although these changes might actually be gradual. Observations of groundwater conditions were made during drilling and are presented on the boring logs. Groundwater conditions observed during drilling represent a short-term condition and may or may not be representative of the long-term groundwater conditions at the site. Groundwater conditions observed during drilling should be considered approximate. Borings were backfilled by the driller in accordance with Washington State Department of Ecology (Ecology) requirements. Groundwater Monitoring Well The monitoring well at boring B-2 was completed to a depth of approximately 30 feet bgs with a screened interval between approximately 20 and 30 feet bgs. The well was completed with a steel monument, flush with the surrounding grade. An electronic data logger was installed in the well to record groundwater levels on a regular interval. We plan to return to the site on a quarterly basis to retrieve groundwater data. We will KPFF Consulting Engineers | May 5, 2026 Page A-2 File No. 2868-044-00 provide updated groundwater information as an addendum to this report once it is available. It is not currently in our budget to decommission the well after our groundwater monitoring period is complete. We assume the contractor performing the work will be responsible for coordinating monitoring well decommissioning. Wells must be decommissioned by a licensed well driller. The reference well Department of Ecology Well ID number is BOT828. Test Pits Test pits were continuously observed by a geologist from our firm who evaluated and classified the soils encountered, obtained representative soil samples and maintained a detailed log of each test pit. Density was estimated from difficulty of digging and difficulty of sample collection using a hand-held trowel. In addition, pertinent information including soil sample depths, stratigraphy and groundwater seepage was recorded. The soils encountered during excavation were visually classified in general accordance with the system summarized in Figure A-1. The logs of the test pits are presented in Figures A-7 through A-8. The logs are based on our interpretation of the field and laboratory data and indicate the various soils encountered. They also indicate the approximate depths at which the soils or their characteristics change; although the change may be gradual. Representative soil samples were obtained from the test pits, logged, sealed in plastic bags and transported to our laboratory. Laboratory testing is described in Appendix B. The test pits were backfilled with the excavated soils and compacted to the extent practical with the bucket of the excavator. The backfill was not compacted to the requirements of structural fill. Once backfill was complete the test pit area was surfaced with the base coarse gravel that we were able to segregate from the rest of the excavated soils. LABORATORY TESTING Soil samples obtained from the explorations were retained in sealed plastic bags and transported to the GeoEngineers’ laboratory. Representative soil samples were selected for laboratory tests to evaluate pertinent geotechnical engineering characteristics of the soils and refine our field classification, as necessary. The tests were performed in general accordance with test methods of ASTM International (ASTM) or other applicable procedures. The following paragraphs provide a description of the tests performed. Moisture Content (MC) Selected samples were oven dried to estimate the percentage of water (on a mass basis) in the soil. Moisture content tests were completed in general accordance with ASTM Test Method D 2216. The results of these tests are presented on the exploration logs at the depths at which the samples were obtained. Percent Fines (%F) Selected samples were “washed” through the U.S. No. 200 sieve to estimate the relative percentages of coarse- and fine-grained particles in the soil. The percent passing value represents the percentage by weight of the sample finer than the U.S. No. 200 sieve (fines). Tests were conducted in general accordance with ASTM D 1140. Test results are presented on the exploration logs at the respective sample depths. KPFF Consulting Engineers | May 5, 2026 Page A-3 File No. 2868-044-00 Particle Size Gradation - Sieve Analysis (SA) Sieve analyses were performed on selected samples in general accordance with ASTM Test Method D 6913. This test method covers the quantitative determination of the distribution of particle sizes in soils. Typically, the distribution of particle sizes larger than 75 micrometers (µm) is determined by sieving. Figures A-10 and A-11 present the results of our sieve analyses. Organic Content Organic content testing was completed on one representative sample of the Recessional Outwash from each test pit using the ASTM D 2974 test method. This test method evaluates the percentage by weight of organic matter in the soil. The test results are summarized in Table 3 of this report and in Table A-1 below. Cation Exchange Capacity (CEC) CEC testing was performed on a representative sample of the Recessional Outwash from each test pit following the U.S. Environmental Protection Agency (EPA) 9081 test method. CEC testing was performed by Northwest Agricultural Consultants, Inc. under subcontract to GeoEngineers. This test evaluates the total capacity of a soil to hold exchangeable cations. The results of the CEC testing are summarized in Table A-1 below. TABLE A-1. RESULTS OF ORGANIC CONTENT AND CATION EXCHANGE CAPACITY TESTING LOCATION SAMPLE DEPTH (FEET BGS) ORGANIC CONTENT (%) CATION EXCHANGE CAPACITY, CEC (MEQ/100G) PIT-1 8.5 0.9 4.6 PIT-2 8.5 2.2 7.9 Notes: feet bgs = feet below ground surface % = percent by weight of organic matter in the soil meq/100g = milliequivalents per 100 grams of soil Measured groundwater level in exploration,well, or piezometer Measured free product in well or piezometer Distinct contact between soil strata Approximate contact between soil strata Contact between geologic units SYMBOLS TYPICAL DESCRIPTIONS GW GP SW SP SM FINEGRAINED SOILS SILTS ANDCLAYS NOTE: Multiple symbols are used to indicate borderline or dual soil classifications MORE THAN 50%RETAINED ONNO. 200 SIEVE MORE THAN 50%PASSINGNO. 200 SIEVE GRAVEL ANDGRAVELLYSOILS SC LIQUID LIMITLESS THAN 50 (APPRECIABLE AMOUNTOF FINES) (APPRECIABLE AMOUNTOF FINES) COARSEGRAINEDSOILS MAJOR DIVISIONS GRAPH LETTER GM GC ML CL OL SILTS AND CLAYS SANDS WITHFINES SANDANDSANDY SOILS MH CH OH PT (LITTLE OR NO FINES) CLEAN SANDS GRAVELS WITHFINES CLEAN GRAVELS (LITTLE OR NO FINES) WELL-GRADED GRAVELS, GRAVEL -SAND MIXTURES CLAYEY GRAVELS, GRAVEL - SAND -CLAY MIXTURES WELL-GRADED SANDS, GRAVELLYSANDS POORLY-GRADED SANDS, GRAVELLYSAND SILTY SANDS, SAND - SILT MIXTURES CLAYEY SANDS, SAND - CLAYMIXTURES INORGANIC SILTS, ROCK FLOUR,CLAYEY SILTS WITH SLIGHTPLASTICITY INORGANIC CLAYS OF LOW TOMEDIUM PLASTICITY, GRAVELLYCLAYS, SANDY CLAYS, SILTY CLAYS,LEAN CLAYS ORGANIC SILTS AND ORGANIC SILTYCLAYS OF LOW PLASTICITY INORGANIC SILTS, MICACEOUS ORDIATOMACEOUS SILTY SOILS INORGANIC CLAYS OF HIGHPLASTICITY ORGANIC CLAYS AND SILTS OFMEDIUM TO HIGH PLASTICITY PEAT, HUMUS, SWAMP SOILS WITHHIGH ORGANIC CONTENTSHIGHLY ORGANIC SOILS SOIL CLASSIFICATION CHART MORE THAN 50%OF COARSEFRACTION RETAINEDON NO. 4 SIEVE MORE THAN 50%OF COARSEFRACTION PASSINGON NO. 4 SIEVE SILTY GRAVELS, GRAVEL - SAND -SILT MIXTURES POORLY-GRADED GRAVELS,GRAVEL - SAND MIXTURES LIQUID LIMIT GREATERTHAN 50 Contact between soil of the same geologicunit Material Description Contact Graphic Log Contact NOTE: The reader must refer to the discussion in the report text and the logs of explorations for a proper understanding of subsurface conditions.Descriptions on the logs apply only at the specific exploration locations and at the time the explorations were made; they are not warranted to berepresentative of subsurface conditions at other locations or times. Groundwater Contact Blowcount is recorded for driven samplers as the number ofblows required to advance sampler 12 inches (or distance noted).See exploration log for hammer weight and drop. "P" indicates sampler pushed using the weight of the drill rig. "WOH" indicates sampler pushed using the weight of thehammer. Key to Exploration LogsFigure A-1 - ADDITIONAL MATERIAL SYMBOLS SYMBOLS Asphalt Concrete Cement Concrete Crushed Rock/Quarry Spalls Topsoil GRAPH LETTER AC CC SOD Sod/Forest Duff CR DESCRIPTIONS TYPICAL TS No Visible SheenSlight SheenModerate SheenHeavy Sheen Laboratory / Field Tests %F%GALCACPCSDDDSHAMCMDMohsOCPMPIPLPPSATXUCUUVS Sheen Classification NSSSMSHS Percent finesPercent gravelAtterberg limitsChemical analysisLaboratory compaction testConsolidation testDry densityDirect shearHydrometer analysisMoisture contentMoisture content and dry densityMohs hardness scaleOrganic contentPermeability or hydraulic conductivityPlasticity indexPoint load testPocket penetrometerSieve analysisTriaxial compressionUnconfined compressionUnconsolidated undrained triaxial compressionVane shear Continuous Coring Bulk or grab Direct-Push Piston Shelby tube Standard Penetration Test (SPT) Sampler Symbol Descriptions Modified California Sampler (6-inch sleeve) or Dames & Moore Rev. 03/2024 Project: Renton Off Campus Emergency Department Project Location: Renton, Washington Project Number: 2868-044-00 15 22 9 8 Approximately 3 inches of asphalt concrete Approximately 4 inches of base course Silty Sand (SM), medium dense, brown-gray, moist;medium sand; fine gravel. [Recessional Outwash] Becomes loose Silty Sand (SM), medium dense, brown, moist; fine tomedium sand; trace fine to rounded gravel. Becomes loose Becomes medium dense and gray-brown Silty Sand with Gravel (SM), medium dense, brown,moist; fine to coarse gravel. Poorly Graded Sand with Silt (SP-SM), very dense,gray-brown, moist; fine to medium sand. 1 2 3 4 5%F 6SA 8 3 13 13 15 14 9 17 10 24 20 AC CR SM SM SM SP-SM Notes: 41.5 EV LML Holt Services, Inc. Hollow-stem Auger Truck-mounted D-58DrillingEquipmentAutohammer140 (lbs) / 30 (in) Drop WA State Plane NorthNAD83 (feet)1307985.91186575.11 362NAVD88 Easting (X)Northing (Y) Start TotalDepth (ft) Logged By Checked By End Surface Elevation (ft)Vertical Datum Drilled HammerData SystemDatum Driller DrillingMethod Groundwater not observed at time of exploration 4/2/20264/2/2026 Note: See Figure A-1 for explanation of symbols.Coordinates Data Source: Horizontal approximated based on Locational Survey. Vertical approximated based on Locational Survey. Sheet 1 of 2Project Number: Project Location: Project: 2868-044-00 Log of Boring B-1 Figure A-2 Renton Off Campus Emergency Department Renton, Washington Da t e : 4 / 3 0 / 2 6 P a t h : P : \ 2 \ 2 8 6 8 0 4 4 \ G I N T \ 2 8 6 8 0 4 4 0 0 . G P J D B L i b r a r y / L i b r a r y : G E O E N G I N E E R S _ D F _ S T D _ U S _ J U N E _ 2 0 1 7 . G L B / G E I 8 _ G E O T E C H _ S T A N D A R D _ % F _ N O _ G W REMARKS Fi n e s Co n t e n t ( % ) Mo i s t u r e Co n t e n t ( % ) FIELD DATA MATERIALDESCRIPTION Sa m p l e N a m e Te s t i n g Re c o v e r e d ( i n ) In t e r v a l Bl o w s / f o o t Co l l e c t e d S a m p l e De p t h ( f e e t ) 0 5 10 15 20 25 Gr a p h i c L o g Gr o u p Cl a s s i f i c a t i o n El e v a t i o n ( f e e t ) 360 355 350 345 340 Poorly Graded Sand (SP), dense, gray, moist; fine tomedium sand. Becomes very dense 7 8 9 10 13 10.5 16 10 52 43 50 53 SP Sheet 2 of 2Project Number: Project Location: Project: 2868-044-00 Log of Boring B-1 (continued) Figure A-2 Renton Off Campus Emergency Department Renton, Washington Da t e : 4 / 3 0 / 2 6 P a t h : P : \ 2 \ 2 8 6 8 0 4 4 \ G I N T \ 2 8 6 8 0 4 4 0 0 . G P J D B L i b r a r y / L i b r a r y : G E O E N G I N E E R S _ D F _ S T D _ U S _ J U N E _ 2 0 1 7 . G L B / G E I 8 _ G E O T E C H _ S T A N D A R D _ % F _ N O _ G W REMARKS Fi n e s Co n t e n t ( % ) Mo i s t u r e Co n t e n t ( % ) FIELD DATA MATERIALDESCRIPTION Sa m p l e N a m e Te s t i n g Re c o v e r e d ( i n ) In t e r v a l Bl o w s / f o o t Co l l e c t e d S a m p l e De p t h ( f e e t ) 25 30 35 40 Gr a p h i c L o g Gr o u p Cl a s s i f i c a t i o n El e v a t i o n ( f e e t ) 335 330 325 Approximately 3 inches of asphalt concrete Approximately 4 inches of base course Silty Sand with Gravel (SM), loose, brown, moist;trace subangular gravel. Becomes with no gravel Poorly Graded Sand with Silt (SP-SM), mediumdense, brown-yellow, moist. Silty Sand with Gravel (SM), dense, yellow-brown,moist; little, subangular gravel. 1 2 3 4 5SA 6 7 12 11 3 9 4 8 10 16 4 16 34 AC CR SM SP-SM SM Concrete surfaceseal 2-inch Schedule 40PVC well casing 3/8-inch bentoniteseal 2-inch Schedule 40PVC screen,0.010-inch slotwidth Construction sandbackfill 3 18 20 6 8 StartDrilled4/2/2026 HammerData Date MeasuredHorizontalDatum Vertical Datum Easting (X)Northing (Y) DrillingEquipment Top of CasingElevation (ft) Elevation (ft) Groundwater Depth toWater (ft) Notes: Surface Elevation (ft) Logged By Truck-mounted D-58 361.67362.5NAVD88 1308051.81186658.8 WA State Plane NorthNAD83 (feet)Dry 41.5 DrillingMethod4/2/2026 End Checked By DrillerTotalDepth (ft) Autohammer140 (lbs) / 30 (in) Drop EV LML Holt Services, Inc.Hollow-stem Auger/Cal Mod DOE Well I.D.: BOT828A 2-in well was installed on 4/2/2026 to a depth of 30 ft. Note: See Figure A-1 for explanation of symbols.Coordinates Data Source: Horizontal approximated based on Locational Survey. Vertical approximated based on Locational Survey. Surface Monument El e v a t i o n ( f e e t ) 360 355 350 345 340 De p t h ( f e e t ) 0 5 10 15 20 25 FIELD DATA MATERIALDESCRIPTION Sa m p l e N a m e Te s t i n g Wa t e r L e v e l In t e r v a l Re c o v e r e d ( i n ) Bl o w s / f o o t Co l l e c t e d S a m p l e Gr a p h i c L o g Gr o u p Cla s s i f i c a t i o n WELL LOG Mo i s t u r e Co n t e n t ( % ) Fin e s Co n t e n t ( % ) Sheet 1 of 2Project Number: Project Location: Project: 2868-044-00 Log of Boring with a Monitoring Well B-2 Figure A-3 Renton Off Campus Emergency Department Renton, Washington Da t e : 4 / 3 0 / 2 6 P a t h : P : \ 2 \ 2 8 6 8 0 4 4 \ G I N T \ 2 8 6 8 0 4 4 0 0 . G P J D B L i b r a r y / L i b r a r y : G E O E N G I N E E R S _ D F _ S T D _ U S _ J U N E _ 2 0 1 7 . G L B / G E I 8 _ G E O T E C H _ W E L L _ % F Poorly Graded Sand with Silt (SP-SM), very dense,gray-brown, moist. Becomes very dense Grades to dense 7SA 8%F 9 10 14 10 10 12 38 50 51 49 SP-SM 30 7 5 13 7 El e v a t i o n ( f e e t ) 335 330 325 De p t h ( f e e t ) 25 30 35 40 FIELD DATA MATERIALDESCRIPTION Sa m p l e N a m e Te s t i n g Wa t e r L e v e l In t e r v a l Re c o v e r e d ( i n ) Bl o w s / f o o t Co l l e c t e d S a m p l e Gr a p h i c L o g Gr o u p Cl a s s i f i c a t i o n WELL LOG Mo i s t u r e Co n t e n t ( % ) Fi n e s Co n t e n t ( % ) Sheet 2 of 2Project Number: Project Location: Project: 2868-044-00 Log of Boring with a Monitoring Well B-2 (continued) Figure A-3 Renton Off Campus Emergency Department Renton, Washington Da t e : 4 / 3 0 / 2 6 P a t h : P : \ 2 \ 2 8 6 8 0 4 4 \ G I N T \ 2 8 6 8 0 4 4 0 0 . G P J D B L i b r a r y / L i b r a r y : G E O E N G I N E E R S _ D F _ S T D _ U S _ J U N E _ 2 0 1 7 . G L B / G E I 8 _ G E O T E C H _ W E L L _ % F 25 27 9 10 Approximately 3 inches of asphalt concrete Approximately 4 inches of base course Silty Sand (SM), medium dense, gray, moist; fine tomedium sand. [Recessional Outwash] Silty Sand (SM), medium dense, gray-brown, moist;medium to coarse sand; trace gravel. Poorly Graded Sand with Silt (SP-SM), dense,gray-brown, moist; medium to coarse sand; few totrace gravel; few silt. 1%F 2 3SA 4 5 15 17 12 13 15 25 19 22 25 42 AC CR SM SM SP-SM Notes: 16.5 EV LML Holt Services, Inc. Hollow-stem Auger Truck-mounted D-58DrillingEquipmentAutohammer140 (lbs) / 30 (in) Drop WA State Plane NorthNAD83 (feet)1308240.92186651.61 364NAVD88 Easting (X)Northing (Y) Start TotalDepth (ft) Logged By Checked By End Surface Elevation (ft)Vertical Datum Drilled HammerData SystemDatum Driller DrillingMethod Groundwater not observed at time of exploration 4/3/20264/3/2026 Note: See Figure A-1 for explanation of symbols.Coordinates Data Source: Horizontal approximated based on Locational Survey. Vertical approximated based on Locational Survey. Sheet 1 of 1Project Number: Project Location: Project: 2868-044-00 Log of Boring B-3 Figure A-4 Renton Off Campus Emergency Department Renton, Washington Da t e : 4 / 3 0 / 2 6 P a t h : P : \ 2 \ 2 8 6 8 0 4 4 \ G I N T \ 2 8 6 8 0 4 4 0 0 . G P J D B L i b r a r y / L i b r a r y : G E O E N G I N E E R S _ D F _ S T D _ U S _ J U N E _ 2 0 1 7 . G L B / G E I 8 _ G E O T E C H _ S T A N D A R D _ % F _ N O _ G W REMARKS Fi n e s Co n t e n t ( % ) Mo i s t u r e Co n t e n t ( % ) FIELD DATA MATERIALDESCRIPTION Sa m p l e N a m e Te s t i n g Re c o v e r e d ( i n ) In t e r v a l Bl o w s / f o o t Co l l e c t e d S a m p l e De p t h ( f e e t ) 0 5 10 15 Gr a p h i c L o g Gr o u p Cl a s s i f i c a t i o n El e v a t i o n ( f e e t ) 360 355 350 3213 Approximately 3 inches of asphalt concrete Approximately 4 inches of base course Poorly Graded Sand with Silt (SP-SM), loose, brown,moist; fine to medium sand. [RecessionalOutwash] Silty Sand (SM), medium dense, brown, moist. Silty Sand (SM), dense, gray-brown, moist; fine tomedium sand. Poorly Graded Sand with Silt (SP-SM), dense,gray-brown, moist. 1 2%F 3 4 5 10.5 15 14 13 14 7 17 15 31 41 AC CR SP-SM SM SM SP-SM Notes: 20 EV LML Holt Services, Inc. Hollow-stem Auger Truck-mounted D-58DrillingEquipmentAutohammer140 (lbs) / 30 (in) Drop WA State Plane NorthNAD83 (feet)1308174.88186543.85 362NAVD88 Easting (X)Northing (Y) Start TotalDepth (ft) Logged By Checked By End Surface Elevation (ft)Vertical Datum Drilled HammerData SystemDatum Driller DrillingMethod Groundwater not observed at time of exploration 4/3/20264/3/2026 Note: See Figure A-1 for explanation of symbols.Coordinates Data Source: Horizontal approximated based on Locational Survey. Vertical approximated based on Locational Survey. Sheet 1 of 1Project Number: Project Location: Project: 2868-044-00 Log of Boring B-4 Figure A-5 Renton Off Campus Emergency Department Renton, Washington Da t e : 4 / 3 0 / 2 6 P a t h : P : \ 2 \ 2 8 6 8 0 4 4 \ G I N T \ 2 8 6 8 0 4 4 0 0 . G P J D B L i b r a r y / L i b r a r y : G E O E N G I N E E R S _ D F _ S T D _ U S _ J U N E _ 2 0 1 7 . G L B / G E I 8 _ G E O T E C H _ S T A N D A R D _ % F _ N O _ G W REMARKS Fi n e s Co n t e n t ( % ) Mo i s t u r e Co n t e n t ( % ) FIELD DATA MATERIALDESCRIPTION Sa m p l e N a m e Te s t i n g Re c o v e r e d ( i n ) In t e r v a l Bl o w s / f o o t Co l l e c t e d S a m p l e De p t h ( f e e t ) 0 5 10 15 20 Gr a p h i c L o g Gr o u p Cl a s s i f i c a t i o n El e v a t i o n ( f e e t ) 360 355 350 345 25 35 24 12 14 10 Approximately 4 inches of asphalt concrete Approximately 4 inches of base course Silty Sand (SM), medium dense, gray, moist; fine tomedium sand. [Recessional Outwash] Trace gravel Becomes brown Poorly Graded Sand with Silt (SP-SM), loose, brown,moist. 1%F 2 3SA 4%F 5 15 7 14 13 7 20 19 9 18 9 AC CR SM SP-SM Notes: 16.5 EV LML Holt Services, Inc. Hollow-stem Auger/Cal Mod Truck-mounted D-58DrillingEquipmentAutohammer140 (lbs) / 30 (in) Drop WA State Plane NorthNAD83 (feet)1308075.46186513.6 362NAVD88 Easting (X)Northing (Y) Start TotalDepth (ft) Logged By Checked By End Surface Elevation (ft)Vertical Datum Drilled HammerData SystemDatum Driller DrillingMethod Groundwater not observed at time of exploration 4/3/20264/3/2026 Note: See Figure A-1 for explanation of symbols.Coordinates Data Source: Horizontal approximated based on Locational Survey. Vertical approximated based on Locational Survey. Sheet 1 of 1Project Number: Project Location: Project: 2868-044-00 Log of Boring B-5 Figure A-6 Renton Off Campus Emergency Department Renton, Washington Da t e : 4 / 3 0 / 2 6 P a t h : P : \ 2 \ 2 8 6 8 0 4 4 \ G I N T \ 2 8 6 8 0 4 4 0 0 . G P J D B L i b r a r y / L i b r a r y : G E O E N G I N E E R S _ D F _ S T D _ U S _ J U N E _ 2 0 1 7 . G L B / G E I 8 _ G E O T E C H _ S T A N D A R D _ % F _ N O _ G W REMARKS Fi n e s Co n t e n t ( % ) Mo i s t u r e Co n t e n t ( % ) FIELD DATA MATERIALDESCRIPTION Sa m p l e N a m e Te s t i n g Re c o v e r e d ( i n ) In t e r v a l Bl o w s / f o o t Co l l e c t e d S a m p l e De p t h ( f e e t ) 0 5 10 15 Gr a p h i c L o g Gr o u p Cl a s s i f i c a t i o n El e v a t i o n ( f e e t ) 360 355 350 Approximately 4 inches of asphalt concrete Silty Gravel with Sand (GM), medium dense, gray-brown, moist. [BaseCourse] Silty Sand with Gravel (SM), medium dense, gray-brown, moist; mostlyfine sand; few to little gravel; ocassionally weakly cemented.[Recessional Outwash] Test pit terminated at approximately 8½ feet AC GM SM S-1 S-2 S-3 S-4SA 8 Infiltration test completed at 8 feet25 Notes: See Figure A-1 for explanation of symbols.The depths on the test pit logs are based on an average of measurements across the test pit and should be considered accurate to ½ foot.Coordinates Data Source: Horizontal approximated based on Locational Survey. Vertical approximated based on Locational Survey. Da t e : 4 / 3 0 / 2 6 P a t h : P : \ 2 \ 2 8 6 8 0 4 4 \ G I N T \ 2 8 6 8 0 4 4 0 0 . G P J D B L i b r a r y / L i b r a r y : G E O E N G I N E E R S _ D F _ S T D _ U S _ J U N E _ 2 0 1 7 . G L B / G E I 8 _ T E S T P I T _ 1 P _ G E O T E C _ % F Sheet 1 of 1Project Number: Project Location: Project: 2868-044-00 Log of Test Pit PIT-1 Figure A-7 Renton Off Campus Emergency Department Renton, Washington El e v a t i o n ( f e e t ) 361 360 359 358 357 356 355 354 De p t h ( f e e t ) 1 2 3 4 5 6 7 8 Te s t i n g S a m p l e Gr a p h i c L o g SAMPLE MATERIALDESCRIPTION Gr o u p Cla s s i f i c a t i o n Sa m p l e N a m e Te s t i n g Mo i s t u r e Co n t e n t ( % ) REMARKS Fin e s Co n t e n t ( % ) DateExcavated Surface Elevation (ft)Vertical Datum Coordinate SystemHorizontal DatumEasting (X)Northing (Y) TotalDepth (ft)4/16/2026 8.5 362NAVD88 1308186.05186593.09 WA State Plane NorthNAD83 (feet) EV Checked By LML Groundwater not observed Caving not observedEquipment John Deere 356 Logged By Excavator Holt Services, Inc. Approximately 4 inches of asphalt concrete Silty Gravel with Sand (GM), medium dense, gray, moist; concretetreated base course. Silty Sand with Gravel (SM), medium dense. gray-brown, moist; mostlyfine sand; few gravel; organics (wood debris). [RecessionalOutwash] Becomes gray Silty Sand with Gravel and Cobbles (SM), medium dense, lightgray-brown, moist; mostly fine sand; few gravel; trace cobbles. Test pit terminated at approximately 8½ feet AC GM SM SM S-1 S-2 S-3 S-4SA 7 Minor groundwater seepage observed at 1½ feet Infiltration test completed at 8 feet21 Notes: See Figure A-1 for explanation of symbols.The depths on the test pit logs are based on an average of measurements across the test pit and should be considered accurate to ½ foot.Coordinates Data Source: Horizontal approximated based on Locational Survey. Vertical approximated based on Locational Survey. Da t e : 4 / 3 0 / 2 6 P a t h : P : \ 2 \ 2 8 6 8 0 4 4 \ G I N T \ 2 8 6 8 0 4 4 0 0 . G P J D B L i b r a r y / L i b r a r y : G E O E N G I N E E R S _ D F _ S T D _ U S _ J U N E _ 2 0 1 7 . G L B / G E I 8 _ T E S T P I T _ 1 P _ G E O T E C _ % F Sheet 1 of 1Project Number: Project Location: Project: 2868-044-00 Log of Test Pit PIT-2 Figure A-8 Renton Off Campus Emergency Department Renton, Washington El e v a t i o n ( f e e t ) 360 359 358 357 356 355 354 353 De p t h ( f e e t ) 1 2 3 4 5 6 7 8 Te s t i n g S a m p l e Gr a p h i c L o g SAMPLE MATERIALDESCRIPTION Gr o u p Cla s s i f i c a t i o n Sa m p l e N a m e Te s t i n g Mo i s t u r e Co n t e n t ( % ) REMARKS Fin e s Co n t e n t ( % ) DateExcavated Surface Elevation (ft)Vertical Datum Coordinate SystemHorizontal DatumEasting (X)Northing (Y) TotalDepth (ft)4/16/2026 8.5 361NAVD88 1308038.26186499.18 WA State Plane NorthNAD83 (feet) EV Checked By LML Groundwater not observed Caving not observedEquipment John Deere 356 Logged By Excavator Holt Services, Inc. MEDIUM FINE 3/8”3” 1.5”#4 #10 #20 #40 #60 #1003/4” 02868-044-00 Date Exported: 04/29/2026 Soil Description Boring Number Depth (feet) B-1 B-2 B-2 B-3 20 15 25 7.5 Silty sand with gravel (SM) Poorly graded sand with silt (SP-SM) Silty sand (SM) Silty sand (SM) Symbol Moisture (%) 8 6 7 10 Note: This report may not be reproduced, except in full, without written approval of GeoEngineers, Inc. Test results are applicable only to the specific sample on which they were performed, and should not be interpreted as representative of any other samples obtained at other times, depths or locations, or generated by separate operations or processes. The grain size analysis results were obtained in general accordance with ASTM D 6913. Figure A9 Sieve Analysis Results Renton off Campus Emergency Department Renton, Washington #200 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.11101001000 PE R C E N T P A S S I N G B Y W E I G H T GRAIN SIZE IN MILLIMETERS U.S. STANDARD SIEVE SIZE SAND SILT OR CLAYCOBBLESGRAVEL COARSECOARSE FINE MEDIUM FINE 3/8”3” 1.5”#4 #10 #20 #40 #60 #1003/4” 02868-044-00 Date Exported: 04/29/2026 Soil Description Boring Number Depth (feet) B-4 B-5 PIT-1 PIT-2 5 7.5 8 8 Silty sand (SM) Silty sand (SM) Silty sand with gravel (SM) Silty sand with gravel (SM) Symbol Moisture (%) 13 14 8 7 Note: This report may not be reproduced, except in full, without written approval of GeoEngineers, Inc. Test results are applicable only to the specific sample on which they were performed, and should not be interpreted as representative of any other samples obtained at other times, depths or locations, or generated by separate operations or processes. The grain size analysis results were obtained in general accordance with ASTM D 6913. Figure A10 Sieve Analysis Results Renton off Campus Emergency Department Renton, Washington #200 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.11101001000 PE R C E N T P A S S I N G B Y W E I G H T GRAIN SIZE IN MILLIMETERS U.S. STANDARD SIEVE SIZE SAND SILT OR CLAYCOBBLESGRAVEL COARSECOARSE FINE Appendix B Infiltration Testing KPFF Consulting Engineers | May 5, 2026 Page B-1 File No. 2868-044-00 Infiltration Testing PILOT INFILTRATION TESTS We conducted small-scale pilot infiltration tests (PITs) in test pits PIT-1 and PIT-2 on April 16, 2026. Figure 2, Site Plan, shows the approximate location of the test pits where the PITs were performed. The infiltration tests were completed in general accordance with the guidelines provided in the City of Renton Surface Water Design Manual which references and is based on the King County 2021 Surface Water Design Manual (2021 KCSWDM). The following is a summary of test methods, field measured infiltration rates and correction factors used for developing the design soil infiltration rate for the site. METHODOLOGY AND TESTING PROCEDURES Test pits PIT-1 and PIT-2 were initially excavated with a John Deere 35G excavator to approximately 8 feet below the ground surface. We selected PIT locations and depths based on conversations with the project team and utility access considerations. We performed both small-scale PITs in the native Recessional Outwash soils. During testing, a graduated grade rod or tape measure was placed at the base of the excavation as a visual reference for monitoring water levels during testing. A piezoelectric pressure transducer was placed at the base of the excavation to provide accurate water level records in 5-second intervals throughout the duration of the tests. Water used for the infiltration tests in PIT-1 and PIT-2 was provided by water trucks using 2½ and 2-inch hoses. Initial filling and maintaining of the water level in the PITs was performed by monitoring the declining water level in a series of stages. The excavation was filled to a predetermined depth (approximately 14 inches) for the 6-hour pre-soak period. During the pre-soak, the water level was allowed to drain approximately 2 inches before the pit was refilled to the initial level again to maintain a constant minimum depth of 12 inches. This draining and refilling process was repeated as needed in succession (stages). At the end of the 6-hour pre-soak period, the successive filling and draining was repeated at the same 12 and 14 inches of water depth for an additional hour, which is considered the testing period. By periodically refilling the excavation to the starting level, then allowing the water level to drop between two predetermined levels, the apparent infiltration rate for each cycle was determined accurately using measurements from the pressure transducer. The rate of decline in the falling water levels recorded after each filling cycle was used to calculate the apparent infiltration rate for each stage of the test. The overall testing process for each PIT took approximately 8 hours with water levels measured continuously (every 5 seconds). The water-level measurements for the PITs and plots of the measured infiltration rates calculated during each stage of the small-scale PIT in test pits PIT-1 and PIT-2 are shown in Figures B-1 and B-2. After completing the PITs, the test pits were excavated an additional ½ foot below the infiltration testing depth to observe and sample the soils below the level of the infiltration testing. KPFF Consulting Engineers | May 5, 2026 Page B-2 File No. 2868-044-00 CORRECTION FACTORS The design infiltration rate is determined by applying correction factors to the saturated infiltration rate measured during testing. The correction factors account for uncertainties in testing, depth to the water table or impervious strata, infiltration receptor geometry and long-term reductions in permeability due to biological activity and accumulation of fines. Equation 5-11 of the 2021 KCSWDM was developed to account for these factors. This equation estimates the maximum design infiltration rate (Idesign). 𝐼𝐼𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑=𝐼𝐼𝑚𝑚𝑑𝑑𝑚𝑚𝑑𝑑𝑚𝑚𝑚𝑚𝑑𝑑𝑑𝑑∗𝐹𝐹𝑡𝑡𝑑𝑑𝑑𝑑𝑡𝑡𝑑𝑑𝑑𝑑𝑑𝑑∗𝐹𝐹𝑑𝑑𝑑𝑑𝑔𝑔𝑚𝑚𝑑𝑑𝑡𝑡𝑚𝑚𝑔𝑔∗𝐹𝐹𝑝𝑝𝑝𝑝𝑚𝑚𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑 (Equation 5-11) Ftesting accounts for uncertainties in the testing method. For small and large-scale PITs, Ftesting = 0.5. Fgeometry accounts for the influence of facility geometry and depth to the water table or impervious strata on the actual infiltration rate. Fgeometry must be between 0.25 and 1.0 as determined by Equation 5-12: Fgeometry = 4 D/W + 0.05 (Equation 5-12) Where D = depth from the bottom of the proposed facility to the maximum wet-season water table or nearest impervious layer, whichever is less, and W = width of the facility. We did not observe what we interpret to be an impervious layer in our explorations. Until additional groundwater data is collected at the site we recommend assuming a design depth to groundwater of 40 feet below existing site grades (about Elevation 322 feet). While the dimensions of the proposed infiltration facilities are not known, we anticipate that the recommended design groundwater depth/elevation will correspond to a calculated geometry factor of 1.0. As discussed in Section 3.7.4, a final geometry factor should be calculated once more groundwater data is collected and the facility dimensions are known. The design infiltration rate used for the facility should consider the finalized geometry factor. Fplugging accounts for reductions in infiltration rates over the long term due to plugging of soils. We recommend a correction factor Fplugging of 0.7 because the soils encountered were loams and sandy loams. All currently recommended correction factors and the total correction factor are provided in Table B-1. TABLE B-1. RECOMMENDED INFILTRATION CORRECTION FACTORS FTESTING FGEOMETRY FPLUGGING TOTAL CORRECTION FACTOR 0.5 1.0 0.7 0.35 Notes: Fgeometry = must be verified once final facility dimensions are known and additional groundwater data is collected. Figure B-1 PIT-1 Infiltration Testing Renton Off Campus Emergency Department Renton, Washington 02868-044-00 Date Exported: 4/22/2026 Notes: 1. The small-scale PIT was completed on April 16, 2026. 2. The testing head range was analyzed during the 1-hour testing period. 3. Measured infiltration rates are corrected according to a correction factor of 0.35 outlined in Appendix B. 0.80 0.85 0.90 0.95 1.00 1.05 1.10 1.15 1.20 1.25 1.30 Wa t e r H e i g h t A b o v e S e n s o r ( f e e t ) Time Raw Data Testing Head Range Analyzed Section 0 1 2 3 4 5 6 7 8 9 In f i l t r a t i o n R a t e ( i n / h r ) Stage # Pre-Soak Phase Testing Phase Pre-Soak Testing Phase Figure B-2 PIT-2 Infiltration Testing 02868-044-00 Date Exported: 4/22/2026 Notes: 1. The small-scale PIT was completed on April 16, 2026. 2. The testing head range was analyzed during the 1-hour testing period. 3. Measured infiltration rates are corrected according to a correction factor of 0.35 outlined in Appendix B. Renton Off Campus Emergency Department Renton, Washington 0.80 0.85 0.90 0.95 1.00 1.05 1.10 1.15 1.20 1.25 1.30 Wa t e r H e i g h t A b o v e S e n s o r ( f e e t ) Time Raw Data Testing Head Range Analyzed Section Pre-Soak Testing Phase 0 0.5 1 1.5 2 2.5 In f i l t r a t i o n R a t e ( i n / h r ) Stage # Pre-Soak Phase Testing Phase Appendix C Report Limitations and Guidelines for Use KPFF Consulting Engineers | May 5, 2026 Page C-1 File No. 2868-044-00 Appendix C Report Limitations and Guidelines for Use1 This appendix provides information to help you manage your risks with respect to the use of this report. READ THESE PROVISIONS CLOSELY It is important to recognize that the geoscience practices (geotechnical engineering, geology and environmental science) rely on professional judgment and opinion to a greater extent than other engineering and natural science disciplines, where more precise and/or readily observable data may exist. To help clients better understand how this difference pertains to our services, GeoEngineers includes the following explanatory “limitations” provisions in its reports. Please confer with GeoEngineers if you need to know more how these “Report Limitations and Guidelines for Use” apply to your project or site. GEOTECHNICAL SERVICES ARE PERFORMED FOR SPECIFIC PURPOSES, PERSONS AND PROJECTS This report has been prepared for KPFF Consulting Engineers and for the Project(s) specifically identified in the report. The information contained herein is not applicable to other sites or projects. GeoEngineers structures its services to meet the specific needs of its clients. No party other than the party to whom this report is addressed may rely on the product of our services unless we agree to such reliance in advance and in writing. Within the limitations of the agreed scope of services for the Project, and its schedule and budget, our services have been executed in accordance with our signed agreement for this project executed on March 26, 2026, and generally accepted geotechnical practices in this area at the time this report was prepared. We do not authorize, and will not be responsible for, the use of this report for any purposes or projects other than those identified in the report. A GEOTECHNICAL ENGINEERING OR GEOLOGIC REPORT IS BASED ON A UNIQUE SET OF PROJECT-SPECIFIC FACTORS This report has been prepared for the Renton Off Campus Emergency Department project in Renton, Washington. GeoEngineers considered a number of unique, project-specific factors when establishing the scope of services for this project and report. Unless GeoEngineers specifically indicates otherwise, it is important not to rely on this report if it was: ■ Not prepared for you, ■ Not prepared for your project, ■ Not prepared for the specific site explored, or ■ Completed before important project changes were made. 1 Developed based on material provided by GBA, GeoProfessional Business Association; www.geoprofessional.org. KPFF Consulting Engineers | May 5, 2026 Page C-2 File No. 2868-044-00 For example, changes that can affect the applicability of this report include those that affect: ■ The function of the proposed structure; ■ Elevation, configuration, location, orientation or weight of the proposed structure; ■ Composition of the design team; or ■ Project ownership. If changes occur after the date of this report, GeoEngineers cannot be responsible for any consequences of such changes in relation to this report unless we have been given the opportunity to review our interpretations and recommendations. Based on that review, we can provide written modifications or confirmation, as appropriate. ENVIRONMENTAL CONCERNS ARE NOT COVERED Unless environmental services were specifically included in our scope of services, this report does not provide any environmental findings, conclusions, or recommendations, including but not limited to, the likelihood of encountering underground storage tanks or regulated contaminants. INFORMATION PROVIDED BY OTHERS GeoEngineers has relied upon certain data or information provided or compiled by others in the performance of our services. Although we use sources that we reasonably believe to be trustworthy, GeoEngineers cannot warrant or guarantee the accuracy or completeness of information provided or compiled by others. SUBSURFACE CONDITIONS CAN CHANGE This geotechnical or geologic report is based on conditions that existed at the time the study was performed. The findings and conclusions of this report may be affected by the passage of time, by man-made events such as construction on or adjacent to the site, new information or technology that becomes available subsequent to the report date, or by natural events such as floods, earthquakes, slope instability or groundwater fluctuations. If more than a few months have passed since issuance of our report or work product, or if any of the described events may have occurred, please contact GeoEngineers before applying this report for its intended purpose so that we may evaluate whether changed conditions affect the continued reliability or applicability of our conclusions and recommendations. GEOTECHNICAL AND GEOLOGIC FINDINGS ARE PROFESSIONAL OPINIONS Our interpretations of subsurface conditions are based on field observations from widely spaced sampling locations at the site. Site exploration identifies the specific subsurface conditions only at those points where subsurface tests are conducted or samples are taken. GeoEngineers reviewed field and laboratory data and then applied its professional judgment to render an informed opinion about subsurface conditions at other locations. Actual subsurface conditions may differ, sometimes significantly, from the opinions presented in this report. Our report, conclusions and interpretations are not a warranty of the actual subsurface conditions. KPFF Consulting Engineers | May 5, 2026 Page C-3 File No. 2868-044-00 GEOTECHNICAL ENGINEERING REPORT RECOMMENDATIONS ARE NOT FINAL We have developed the following recommendations based on data gathered from subsurface investigation(s). These investigations sample just a small percentage of a site to create a snapshot of the subsurface conditions elsewhere on the site. Such sampling on its own cannot provide a complete and accurate view of subsurface conditions for the entire site. Therefore, the recommendations included in this report are preliminary and should not be considered final. GeoEngineers’ recommendations can be finalized only by observing actual subsurface conditions revealed during construction. GeoEngineers cannot assume responsibility or liability for the recommendations in this report if we do not perform construction observation. We recommend that you allow sufficient monitoring, testing and consultation during construction by GeoEngineers to confirm that the conditions encountered are consistent with those indicated by the explorations, to provide recommendations for design changes if the conditions revealed during the work differ from those anticipated, and to evaluate whether earthwork activities are completed in accordance with our recommendations. Retaining GeoEngineers for construction observation for this project is the most effective means of managing the risks associated with unanticipated conditions. If another party performs field observation and confirms our expectations, the other party must take full responsibility for both the observations and recommendations. Please note, however, that another party would lack our project- specific knowledge and resources. A GEOTECHNICAL ENGINEERING OR GEOLOGIC REPORT COULD BE SUBJECT TO MISINTERPRETATION Misinterpretation of this report by members of the design team or by contractors can result in costly problems. GeoEngineers can help reduce the risks of misinterpretation by conferring with appropriate members of the design team after submitting the report, reviewing pertinent elements of the design team’s plans and specifications, participating in pre-bid and preconstruction conferences, and providing construction observation. DO NOT REDRAW THE EXPLORATION LOGS Geotechnical engineers and geologists prepare final boring and testing logs based upon their interpretation of field logs and laboratory data. The logs included in a geotechnical engineering or geologic report should never be redrawn for inclusion in architectural or other design drawings. Photographic or electronic reproduction is acceptable but separating logs from the report can create a risk of misinterpretation. GIVE CONTRACTORS A COMPLETE REPORT AND GUIDANCE To help reduce the risk of problems associated with unanticipated subsurface conditions, GeoEngineers recommends giving contractors the complete geotechnical engineering or geologic report, including these “Report Limitations and Guidelines for Use.” When providing the report, you should preface it with a clearly written letter of transmittal that: ■ Advises contractors that the report was not prepared for purposes of bid development and that its accuracy is limited; and ■ Encourages contractors to confer with GeoEngineers and/or to conduct additional study to obtain the specific types of information they need or prefer. KPFF Consulting Engineers | May 5, 2026 Page C-4 File No. 2868-044-00 CONTRACTORS ARE RESPONSIBLE FOR SITE SAFETY ON THEIR OWN CONSTRUCTION PROJECTS Our geotechnical recommendations are not intended to direct the contractor’s procedures, methods, schedule or management of the work site. The contractor is solely responsible for job site safety and for managing construction operations to minimize risks to on-site personnel and adjacent properties. BIOLOGICAL POLLUTANTS GeoEngineers’ Scope of Work specifically excludes the investigation, detection, prevention or assessment of the presence of Biological Pollutants. Accordingly, this report does not include any interpretations, recommendations, findings or conclusions regarding the detecting, assessing, preventing or abating of Biological Pollutants, and no conclusions or inferences should be drawn regarding Biological Pollutants as they may relate to this project. The term “Biological Pollutants” includes, but is not limited to, molds, fungi, spores, bacteria and viruses, and/or any of their byproducts. A Client that desires these specialized services is advised to obtain them from a consultant who offers services in this specialized field. APPENDIX D WWHM Report WWHM2012 PROJECT REPORT MC RENTON OCED - Basin Modeling 5/5/2026 11:04:48 AM Page 2 General Model Information WWHM2012 Project Name:MC RENTON OCED - Basin Modeling Site Name:MC RENTON Site Address:3116 SUNSET BLVD NE City:RENTON Report Date:5/5/2026 Gage:Seatac Data Start:1948/10/01 Data End:2009/09/30 Timestep:15 Minute Precip Scale:0.000 (adjusted) Version Date:2025/05/13 Version:4.3.2 POC Thresholds Low Flow Threshold for POC1:50 Percent of the 2 Year High Flow Threshold for POC1:50 Year Low Flow Threshold for POC2:50 Percent of the 2 Year High Flow Threshold for POC2:50 Year Low Flow Threshold for POC3:50 Percent of the 2 Year High Flow Threshold for POC3:50 Year MC RENTON OCED - Basin Modeling 5/5/2026 11:04:48 AM Page 3 Landuse Basin Data Predeveloped Land Use Drainage Basin 1 (PURPLE) Bypass:No GroundWater:No Pervious Land Use acre A B, Lawn, Flat 0.014 Pervious Total 0.014 Impervious Land Use acre SIDEWALKS FLAT 0.68 Impervious Total 0.68 Basin Total 0.694 Element Flow Componants: Surface Interflow Groundwater Componant Flows To: POC 1 POC 1 MC RENTON OCED - Basin Modeling 5/5/2026 11:04:48 AM Page 4 Drainage Basin 2 (BLUE) Bypass:No GroundWater:No Pervious Land Use acre A B, Lawn, Flat 0.211 Pervious Total 0.211 Impervious Land Use acre SIDEWALKS FLAT 0.869 Impervious Total 0.869 Basin Total 1.08 Element Flow Componants: Surface Interflow Groundwater Componant Flows To: POC 2 POC 2 MC RENTON OCED - Basin Modeling 5/5/2026 11:04:48 AM Page 5 Drainage Basin 3 (BYPASS, ORANGE) Bypass:No GroundWater:No Pervious Land Use acre A B, Lawn, Flat 0.085 Pervious Total 0.085 Impervious Land Use acre SIDEWALKS FLAT 0.093 Impervious Total 0.093 Basin Total 0.178 Element Flow Componants: Surface Interflow Groundwater Componant Flows To: POC 3 POC 3 MC RENTON OCED - Basin Modeling 5/5/2026 11:04:48 AM Page 6 Mitigated Land Use Drainage Basin 1 (PURPLE) Bypass:No GroundWater:No Pervious Land Use acre A B, Lawn, Flat 0.015 Pervious Total 0.015 Impervious Land Use acre SIDEWALKS FLAT 0.679 Impervious Total 0.679 Basin Total 0.694 Element Flow Componants: Surface Interflow Groundwater Componant Flows To: POC 1 POC 1 MC RENTON OCED - Basin Modeling 5/5/2026 11:04:48 AM Page 7 Drainage Basin 2 (BLUE) Bypass:No GroundWater:No Pervious Land Use acre A B, Lawn, Flat 0.245 Pervious Total 0.245 Impervious Land Use acre SIDEWALKS FLAT 0.835 Impervious Total 0.835 Basin Total 1.08 Element Flow Componants: Surface Interflow Groundwater Componant Flows To: POC 2 POC 2 MC RENTON OCED - Basin Modeling 5/5/2026 11:04:48 AM Page 8 Drainage Basin 3 (BYPASS, ORANGE) Bypass:No GroundWater:No Pervious Land Use acre A B, Lawn, Flat 0.085 Pervious Total 0.085 Impervious Land Use acre SIDEWALKS FLAT 0.093 Impervious Total 0.093 Basin Total 0.178 Element Flow Componants: Surface Interflow Groundwater Componant Flows To: POC 3 POC 3 MC RENTON OCED - Basin Modeling 5/5/2026 11:04:48 AM Page 9 Routing Elements Predeveloped Routing MC RENTON OCED - Basin Modeling 5/5/2026 11:04:48 AM Page 10 Mitigated Routing MC RENTON OCED - Basin Modeling 5/5/2026 11:04:48 AM Page 11 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area:0.014 Total Impervious Area:0.68 Mitigated Landuse Totals for POC #1 Total Pervious Area:0.015 Total Impervious Area:0.679 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.25935 5 year 0.32765 10 year 0.374062 25 year 0.434272 50 year 0.48036 100 year 0.527571 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.258975 5 year 0.327181 10 year 0.37353 25 year 0.433658 50 year 0.479684 100 year 0.526831 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 0.336 0.335 1950 0.363 0.362 1951 0.210 0.210 1952 0.187 0.186 1953 0.201 0.201 1954 0.211 0.211 1955 0.239 0.239 1956 0.235 0.235 1957 0.267 0.266 1958 0.215 0.215 MC RENTON OCED - Basin Modeling 5/5/2026 11:05:13 AM Page 12 1959 0.220 0.219 1960 0.216 0.215 1961 0.228 0.228 1962 0.199 0.198 1963 0.221 0.220 1964 0.216 0.216 1965 0.275 0.275 1966 0.184 0.184 1967 0.317 0.316 1968 0.360 0.360 1969 0.250 0.250 1970 0.242 0.241 1971 0.288 0.288 1972 0.298 0.298 1973 0.180 0.180 1974 0.263 0.262 1975 0.303 0.302 1976 0.204 0.203 1977 0.220 0.220 1978 0.270 0.269 1979 0.369 0.369 1980 0.331 0.331 1981 0.271 0.271 1982 0.382 0.381 1983 0.311 0.310 1984 0.196 0.196 1985 0.270 0.270 1986 0.234 0.234 1987 0.361 0.361 1988 0.219 0.219 1989 0.274 0.274 1990 0.465 0.464 1991 0.370 0.369 1992 0.194 0.194 1993 0.168 0.168 1994 0.183 0.183 1995 0.240 0.240 1996 0.256 0.256 1997 0.249 0.248 1998 0.252 0.251 1999 0.515 0.514 2000 0.256 0.256 2001 0.282 0.281 2002 0.328 0.328 2003 0.255 0.255 2004 0.482 0.481 2005 0.220 0.220 2006 0.195 0.194 2007 0.450 0.450 2008 0.363 0.363 2009 0.335 0.335 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.5148 0.5141 2 0.4817 0.4810 3 0.4648 0.4644 MC RENTON OCED - Basin Modeling 5/5/2026 11:05:13 AM Page 13 4 0.4502 0.4496 5 0.3820 0.3815 6 0.3698 0.3693 7 0.3692 0.3686 8 0.3630 0.3625 9 0.3629 0.3623 10 0.3615 0.3610 11 0.3601 0.3596 12 0.3359 0.3354 13 0.3351 0.3346 14 0.3312 0.3307 15 0.3285 0.3280 16 0.3167 0.3162 17 0.3109 0.3105 18 0.3027 0.3023 19 0.2983 0.2979 20 0.2881 0.2876 21 0.2816 0.2812 22 0.2750 0.2746 23 0.2743 0.2739 24 0.2709 0.2705 25 0.2703 0.2699 26 0.2697 0.2693 27 0.2668 0.2664 28 0.2628 0.2624 29 0.2563 0.2559 30 0.2562 0.2559 31 0.2553 0.2549 32 0.2516 0.2513 33 0.2503 0.2500 34 0.2486 0.2483 35 0.2415 0.2412 36 0.2402 0.2399 37 0.2391 0.2387 38 0.2352 0.2349 39 0.2343 0.2339 40 0.2280 0.2276 41 0.2207 0.2204 42 0.2205 0.2201 43 0.2201 0.2198 44 0.2196 0.2193 45 0.2193 0.2190 46 0.2164 0.2161 47 0.2155 0.2152 48 0.2153 0.2150 49 0.2110 0.2107 50 0.2102 0.2099 51 0.2036 0.2033 52 0.2015 0.2012 53 0.1986 0.1983 54 0.1962 0.1959 55 0.1948 0.1945 56 0.1942 0.1940 57 0.1866 0.1863 58 0.1838 0.1835 59 0.1830 0.1828 60 0.1801 0.1798 61 0.1682 0.1680 MC RENTON OCED - Basin Modeling 5/5/2026 11:05:13 AM Page 14 MC RENTON OCED - Basin Modeling 5/5/2026 11:05:13 AM Page 15 Duration Flows The Facility PASSED Flow(cfs)Predev Mit Percentage Pass/Fail 0.1297 1837 1826 99 Pass 0.1332 1647 1634 99 Pass 0.1368 1507 1496 99 Pass 0.1403 1353 1346 99 Pass 0.1438 1246 1238 99 Pass 0.1474 1112 1109 99 Pass 0.1509 1028 1021 99 Pass 0.1545 932 924 99 Pass 0.1580 853 848 99 Pass 0.1616 804 796 99 Pass 0.1651 726 723 99 Pass 0.1686 675 670 99 Pass 0.1722 611 606 99 Pass 0.1757 583 575 98 Pass 0.1793 535 531 99 Pass 0.1828 498 498 100 Pass 0.1864 451 450 99 Pass 0.1899 423 422 99 Pass 0.1934 392 390 99 Pass 0.1970 370 368 99 Pass 0.2005 343 339 98 Pass 0.2041 316 315 99 Pass 0.2076 297 296 99 Pass 0.2111 272 270 99 Pass 0.2147 259 256 98 Pass 0.2182 239 237 99 Pass 0.2218 223 223 100 Pass 0.2253 209 205 98 Pass 0.2289 198 197 99 Pass 0.2324 181 181 100 Pass 0.2359 174 172 98 Pass 0.2395 163 162 99 Pass 0.2430 145 145 100 Pass 0.2466 140 139 99 Pass 0.2501 135 134 99 Pass 0.2537 122 122 100 Pass 0.2572 114 114 100 Pass 0.2607 108 108 100 Pass 0.2643 105 105 100 Pass 0.2678 100 100 100 Pass 0.2714 92 92 100 Pass 0.2749 89 88 98 Pass 0.2785 84 84 100 Pass 0.2820 77 76 98 Pass 0.2855 71 71 100 Pass 0.2891 65 65 100 Pass 0.2926 65 64 98 Pass 0.2962 62 62 100 Pass 0.2997 58 58 100 Pass 0.3032 54 54 100 Pass 0.3068 54 54 100 Pass 0.3103 52 52 100 Pass 0.3139 50 50 100 Pass MC RENTON OCED - Basin Modeling 5/5/2026 11:05:13 AM Page 16 0.3174 47 47 100 Pass 0.3210 45 45 100 Pass 0.3245 41 40 97 Pass 0.3280 38 36 94 Pass 0.3316 34 33 97 Pass 0.3351 32 31 96 Pass 0.3387 29 29 100 Pass 0.3422 28 28 100 Pass 0.3458 25 25 100 Pass 0.3493 22 22 100 Pass 0.3528 21 21 100 Pass 0.3564 21 21 100 Pass 0.3599 17 17 100 Pass 0.3635 14 13 92 Pass 0.3670 12 12 100 Pass 0.3705 9 9 100 Pass 0.3741 9 9 100 Pass 0.3776 9 9 100 Pass 0.3812 9 9 100 Pass 0.3847 8 8 100 Pass 0.3883 8 8 100 Pass 0.3918 8 8 100 Pass 0.3953 8 8 100 Pass 0.3989 8 8 100 Pass 0.4024 8 8 100 Pass 0.4060 8 8 100 Pass 0.4095 8 8 100 Pass 0.4131 7 7 100 Pass 0.4166 7 7 100 Pass 0.4201 7 7 100 Pass 0.4237 7 7 100 Pass 0.4272 7 7 100 Pass 0.4308 6 6 100 Pass 0.4343 6 6 100 Pass 0.4379 6 6 100 Pass 0.4414 6 6 100 Pass 0.4449 6 6 100 Pass 0.4485 6 6 100 Pass 0.4520 5 5 100 Pass 0.4556 5 5 100 Pass 0.4591 4 4 100 Pass 0.4626 4 4 100 Pass 0.4662 3 3 100 Pass 0.4697 2 2 100 Pass 0.4733 2 2 100 Pass 0.4768 2 2 100 Pass 0.4804 2 2 100 Pass MC RENTON OCED - Basin Modeling 5/5/2026 11:05:13 AM Page 17 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. MC RENTON OCED - Basin Modeling 5/5/2026 11:05:13 AM Page 18 POC 2 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #2 Total Pervious Area:0.211 Total Impervious Area:0.869 Mitigated Landuse Totals for POC #2 Total Pervious Area:0.245 Total Impervious Area:0.835 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #2 Return Period Flow(cfs) 2 year 0.332689 5 year 0.4212 10 year 0.481444 25 year 0.559699 50 year 0.619666 100 year 0.68115 Flow Frequency Return Periods for Mitigated. POC #2 Return Period Flow(cfs) 2 year 0.320001 5 year 0.4055 10 year 0.463735 25 year 0.53942 50 year 0.597446 100 year 0.656961 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #2 Year Predeveloped Mitigated 1949 0.430 0.413 1950 0.464 0.446 1951 0.274 0.265 1952 0.239 0.229 1953 0.257 0.247 1954 0.272 0.262 1955 0.306 0.294 1956 0.301 0.289 1957 0.341 0.328 1958 0.275 0.264 1959 0.281 0.270 MC RENTON OCED - Basin Modeling 5/5/2026 11:05:37 AM Page 19 1960 0.276 0.265 1961 0.291 0.280 1962 0.254 0.244 1963 0.283 0.272 1964 0.277 0.266 1965 0.353 0.339 1966 0.235 0.226 1967 0.405 0.389 1968 0.460 0.442 1969 0.320 0.307 1970 0.309 0.297 1971 0.368 0.354 1972 0.393 0.381 1973 0.230 0.221 1974 0.336 0.323 1975 0.387 0.372 1976 0.261 0.251 1977 0.282 0.271 1978 0.345 0.331 1979 0.472 0.453 1980 0.423 0.407 1981 0.346 0.333 1982 0.488 0.469 1983 0.397 0.382 1984 0.251 0.241 1985 0.345 0.332 1986 0.299 0.288 1987 0.462 0.444 1988 0.280 0.269 1989 0.350 0.337 1990 0.633 0.617 1991 0.483 0.466 1992 0.248 0.239 1993 0.215 0.207 1994 0.234 0.225 1995 0.307 0.295 1996 0.337 0.326 1997 0.322 0.311 1998 0.322 0.309 1999 0.658 0.632 2000 0.328 0.315 2001 0.360 0.346 2002 0.420 0.403 2003 0.327 0.315 2004 0.616 0.592 2005 0.281 0.270 2006 0.253 0.244 2007 0.575 0.560 2008 0.469 0.452 2009 0.428 0.411 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #2 Rank Predeveloped Mitigated 1 0.6580 0.6322 2 0.6330 0.6167 3 0.6156 0.5915 4 0.5754 0.5602 MC RENTON OCED - Basin Modeling 5/5/2026 11:05:37 AM Page 20 5 0.4882 0.4691 6 0.4828 0.4661 7 0.4718 0.4533 8 0.4690 0.4518 9 0.4637 0.4456 10 0.4620 0.4439 11 0.4602 0.4422 12 0.4301 0.4135 13 0.4282 0.4115 14 0.4233 0.4067 15 0.4198 0.4033 16 0.4047 0.3889 17 0.3974 0.3818 18 0.3934 0.3807 19 0.3869 0.3717 20 0.3681 0.3537 21 0.3598 0.3458 22 0.3529 0.3394 23 0.3505 0.3368 24 0.3462 0.3327 25 0.3454 0.3319 26 0.3446 0.3312 27 0.3411 0.3277 28 0.3374 0.3263 29 0.3358 0.3227 30 0.3278 0.3150 31 0.3274 0.3148 32 0.3223 0.3107 33 0.3216 0.3090 34 0.3199 0.3074 35 0.3087 0.2966 36 0.3070 0.2950 37 0.3055 0.2935 38 0.3006 0.2889 39 0.2994 0.2877 40 0.2913 0.2800 41 0.2832 0.2723 42 0.2817 0.2707 43 0.2814 0.2705 44 0.2807 0.2697 45 0.2804 0.2695 46 0.2765 0.2657 47 0.2758 0.2650 48 0.2752 0.2648 49 0.2743 0.2644 50 0.2718 0.2616 51 0.2606 0.2505 52 0.2575 0.2474 53 0.2538 0.2443 54 0.2532 0.2439 55 0.2508 0.2411 56 0.2482 0.2385 57 0.2386 0.2293 58 0.2351 0.2259 59 0.2340 0.2249 60 0.2301 0.2211 61 0.2150 0.2066 MC RENTON OCED - Basin Modeling 5/5/2026 11:05:37 AM Page 21 MC RENTON OCED - Basin Modeling 5/5/2026 11:05:37 AM Page 22 Duration Flows The Facility PASSED Flow(cfs)Predev Mit Percentage Pass/Fail 0.1663 1789 1555 86 Pass 0.1709 1658 1416 85 Pass 0.1755 1471 1275 86 Pass 0.1801 1332 1141 85 Pass 0.1847 1224 1043 85 Pass 0.1892 1095 950 86 Pass 0.1938 1007 875 86 Pass 0.1984 919 801 87 Pass 0.2030 858 742 86 Pass 0.2076 783 672 85 Pass 0.2121 723 610 84 Pass 0.2167 665 572 86 Pass 0.2213 607 532 87 Pass 0.2259 569 491 86 Pass 0.2305 531 449 84 Pass 0.2350 484 414 85 Pass 0.2396 451 387 85 Pass 0.2442 413 362 87 Pass 0.2488 392 330 84 Pass 0.2533 364 308 84 Pass 0.2579 339 289 85 Pass 0.2625 314 268 85 Pass 0.2671 290 249 85 Pass 0.2717 273 231 84 Pass 0.2762 254 215 84 Pass 0.2808 240 202 84 Pass 0.2854 219 188 85 Pass 0.2900 209 175 83 Pass 0.2946 194 165 85 Pass 0.2991 182 150 82 Pass 0.3037 174 142 81 Pass 0.3083 157 135 85 Pass 0.3129 148 125 84 Pass 0.3175 141 117 82 Pass 0.3220 130 110 84 Pass 0.3266 122 107 87 Pass 0.3312 114 98 85 Pass 0.3358 110 92 83 Pass 0.3403 104 86 82 Pass 0.3449 99 83 83 Pass 0.3495 91 77 84 Pass 0.3541 86 72 83 Pass 0.3587 83 69 83 Pass 0.3632 77 67 87 Pass 0.3678 72 61 84 Pass 0.3724 69 56 81 Pass 0.3770 65 56 86 Pass 0.3816 62 53 85 Pass 0.3861 59 50 84 Pass 0.3907 55 48 87 Pass 0.3953 53 45 84 Pass 0.3999 51 41 80 Pass 0.4045 50 38 76 Pass MC RENTON OCED - Basin Modeling 5/5/2026 11:05:37 AM Page 23 0.4090 46 34 73 Pass 0.4136 44 32 72 Pass 0.4182 40 30 75 Pass 0.4228 36 29 80 Pass 0.4273 33 26 78 Pass 0.4319 30 24 80 Pass 0.4365 29 23 79 Pass 0.4411 26 20 76 Pass 0.4457 25 17 68 Pass 0.4502 23 15 65 Pass 0.4548 22 13 59 Pass 0.4594 20 13 65 Pass 0.4640 17 13 76 Pass 0.4686 15 10 66 Pass 0.4731 13 9 69 Pass 0.4777 13 9 69 Pass 0.4823 12 8 66 Pass 0.4869 10 8 80 Pass 0.4915 8 8 100 Pass 0.4960 8 8 100 Pass 0.5006 8 8 100 Pass 0.5052 8 8 100 Pass 0.5098 8 8 100 Pass 0.5143 8 8 100 Pass 0.5189 8 8 100 Pass 0.5235 8 8 100 Pass 0.5281 8 7 87 Pass 0.5327 8 7 87 Pass 0.5372 8 7 87 Pass 0.5418 8 7 87 Pass 0.5464 8 7 87 Pass 0.5510 7 7 100 Pass 0.5556 7 6 85 Pass 0.5601 7 6 85 Pass 0.5647 7 4 57 Pass 0.5693 7 4 57 Pass 0.5739 6 4 66 Pass 0.5785 5 3 60 Pass 0.5830 5 3 60 Pass 0.5876 4 3 75 Pass 0.5922 4 2 50 Pass 0.5968 4 2 50 Pass 0.6013 3 2 66 Pass 0.6059 3 2 66 Pass 0.6105 3 2 66 Pass 0.6151 3 2 66 Pass 0.6197 2 1 50 Pass MC RENTON OCED - Basin Modeling 5/5/2026 11:05:37 AM Page 24 Water Quality Water Quality BMP Flow and Volume for POC #2 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. MC RENTON OCED - Basin Modeling 5/5/2026 11:05:37 AM Page 25 POC 3 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #3 Total Pervious Area:0.085 Total Impervious Area:0.093 Mitigated Landuse Totals for POC #3 Total Pervious Area:0.085 Total Impervious Area:0.093 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #3 Return Period Flow(cfs) 2 year 0.035952 5 year 0.046321 10 year 0.053623 25 year 0.063366 50 year 0.071011 100 year 0.078998 Flow Frequency Return Periods for Mitigated. POC #3 Return Period Flow(cfs) 2 year 0.035952 5 year 0.046321 10 year 0.053623 25 year 0.063366 50 year 0.071011 100 year 0.078998 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #3 Year Predeveloped Mitigated 1949 0.046 0.046 1950 0.050 0.050 1951 0.031 0.031 1952 0.026 0.026 1953 0.028 0.028 1954 0.030 0.030 1955 0.033 0.033 1956 0.032 0.032 1957 0.037 0.037 1958 0.029 0.029 1959 0.030 0.030 MC RENTON OCED - Basin Modeling 5/5/2026 11:06:03 AM Page 26 1960 0.030 0.030 1961 0.031 0.031 1962 0.027 0.027 1963 0.031 0.031 1964 0.030 0.030 1965 0.038 0.038 1966 0.025 0.025 1967 0.045 0.045 1968 0.049 0.049 1969 0.034 0.034 1970 0.033 0.033 1971 0.039 0.039 1972 0.046 0.046 1973 0.025 0.025 1974 0.036 0.036 1975 0.041 0.041 1976 0.028 0.028 1977 0.030 0.030 1978 0.037 0.037 1979 0.050 0.050 1980 0.045 0.045 1981 0.037 0.037 1982 0.052 0.052 1983 0.043 0.043 1984 0.027 0.027 1985 0.037 0.037 1986 0.032 0.032 1987 0.049 0.049 1988 0.030 0.030 1989 0.038 0.038 1990 0.080 0.080 1991 0.055 0.055 1992 0.027 0.027 1993 0.023 0.023 1994 0.025 0.025 1995 0.033 0.033 1996 0.039 0.039 1997 0.036 0.036 1998 0.034 0.034 1999 0.070 0.070 2000 0.035 0.035 2001 0.039 0.039 2002 0.045 0.045 2003 0.035 0.035 2004 0.066 0.066 2005 0.030 0.030 2006 0.029 0.029 2007 0.076 0.076 2008 0.053 0.053 2009 0.046 0.046 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #3 Rank Predeveloped Mitigated 1 0.0803 0.0803 2 0.0763 0.0763 3 0.0704 0.0704 4 0.0659 0.0659 MC RENTON OCED - Basin Modeling 5/5/2026 11:06:03 AM Page 27 5 0.0550 0.0550 6 0.0529 0.0529 7 0.0523 0.0523 8 0.0505 0.0505 9 0.0496 0.0496 10 0.0494 0.0494 11 0.0493 0.0493 12 0.0463 0.0463 13 0.0461 0.0461 14 0.0458 0.0458 15 0.0453 0.0453 16 0.0449 0.0449 17 0.0446 0.0446 18 0.0425 0.0425 19 0.0414 0.0414 20 0.0394 0.0394 21 0.0393 0.0393 22 0.0385 0.0385 23 0.0382 0.0382 24 0.0375 0.0375 25 0.0371 0.0371 26 0.0370 0.0370 27 0.0369 0.0369 28 0.0365 0.0365 29 0.0360 0.0360 30 0.0359 0.0359 31 0.0354 0.0354 32 0.0352 0.0352 33 0.0344 0.0344 34 0.0342 0.0342 35 0.0330 0.0330 36 0.0329 0.0329 37 0.0327 0.0327 38 0.0322 0.0322 39 0.0320 0.0320 40 0.0312 0.0312 41 0.0312 0.0312 42 0.0307 0.0307 43 0.0302 0.0302 44 0.0302 0.0302 45 0.0301 0.0301 46 0.0300 0.0300 47 0.0298 0.0298 48 0.0296 0.0296 49 0.0296 0.0296 50 0.0294 0.0294 51 0.0285 0.0285 52 0.0280 0.0280 53 0.0276 0.0276 54 0.0272 0.0272 55 0.0269 0.0269 56 0.0266 0.0266 57 0.0256 0.0256 58 0.0252 0.0252 59 0.0251 0.0251 60 0.0246 0.0246 61 0.0230 0.0230 MC RENTON OCED - Basin Modeling 5/5/2026 11:06:03 AM Page 28 MC RENTON OCED - Basin Modeling 5/5/2026 11:06:03 AM Page 29 Duration Flows The Facility PASSED Flow(cfs)Predev Mit Percentage Pass/Fail 0.0180 1744 1744 100 Pass 0.0185 1571 1571 100 Pass 0.0190 1415 1415 100 Pass 0.0196 1269 1269 100 Pass 0.0201 1147 1147 100 Pass 0.0207 1030 1030 100 Pass 0.0212 942 942 100 Pass 0.0217 871 871 100 Pass 0.0223 790 790 100 Pass 0.0228 724 724 100 Pass 0.0233 655 655 100 Pass 0.0239 605 605 100 Pass 0.0244 559 559 100 Pass 0.0249 518 518 100 Pass 0.0255 472 472 100 Pass 0.0260 444 444 100 Pass 0.0265 414 414 100 Pass 0.0271 382 382 100 Pass 0.0276 353 353 100 Pass 0.0282 327 327 100 Pass 0.0287 303 303 100 Pass 0.0292 282 282 100 Pass 0.0298 262 262 100 Pass 0.0303 237 237 100 Pass 0.0308 222 222 100 Pass 0.0314 209 209 100 Pass 0.0319 195 195 100 Pass 0.0324 185 185 100 Pass 0.0330 167 167 100 Pass 0.0335 154 154 100 Pass 0.0340 146 146 100 Pass 0.0346 137 137 100 Pass 0.0351 129 129 100 Pass 0.0357 121 121 100 Pass 0.0362 117 117 100 Pass 0.0367 111 111 100 Pass 0.0373 100 100 100 Pass 0.0378 97 97 100 Pass 0.0383 91 91 100 Pass 0.0389 83 83 100 Pass 0.0394 77 77 100 Pass 0.0399 73 73 100 Pass 0.0405 71 71 100 Pass 0.0410 69 69 100 Pass 0.0415 64 64 100 Pass 0.0421 62 62 100 Pass 0.0426 61 61 100 Pass 0.0432 59 59 100 Pass 0.0437 53 53 100 Pass 0.0442 51 51 100 Pass 0.0448 44 44 100 Pass 0.0453 41 41 100 Pass 0.0458 37 37 100 Pass MC RENTON OCED - Basin Modeling 5/5/2026 11:06:03 AM Page 30 0.0464 32 32 100 Pass 0.0469 30 30 100 Pass 0.0474 27 27 100 Pass 0.0480 26 26 100 Pass 0.0485 25 25 100 Pass 0.0490 23 23 100 Pass 0.0496 21 21 100 Pass 0.0501 18 18 100 Pass 0.0507 17 17 100 Pass 0.0512 17 17 100 Pass 0.0517 17 17 100 Pass 0.0523 15 15 100 Pass 0.0528 15 15 100 Pass 0.0533 14 14 100 Pass 0.0539 13 13 100 Pass 0.0544 13 13 100 Pass 0.0549 13 13 100 Pass 0.0555 10 10 100 Pass 0.0560 10 10 100 Pass 0.0565 10 10 100 Pass 0.0571 10 10 100 Pass 0.0576 10 10 100 Pass 0.0582 10 10 100 Pass 0.0587 9 9 100 Pass 0.0592 8 8 100 Pass 0.0598 8 8 100 Pass 0.0603 8 8 100 Pass 0.0608 8 8 100 Pass 0.0614 8 8 100 Pass 0.0619 7 7 100 Pass 0.0624 7 7 100 Pass 0.0630 6 6 100 Pass 0.0635 5 5 100 Pass 0.0640 5 5 100 Pass 0.0646 4 4 100 Pass 0.0651 4 4 100 Pass 0.0657 4 4 100 Pass 0.0662 3 3 100 Pass 0.0667 3 3 100 Pass 0.0673 3 3 100 Pass 0.0678 3 3 100 Pass 0.0683 3 3 100 Pass 0.0689 3 3 100 Pass 0.0694 3 3 100 Pass 0.0699 3 3 100 Pass 0.0705 2 2 100 Pass 0.0710 2 2 100 Pass MC RENTON OCED - Basin Modeling 5/5/2026 11:06:03 AM Page 31 Water Quality Water Quality BMP Flow and Volume for POC #3 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. MC RENTON OCED - Basin Modeling 5/5/2026 11:06:03 AM Page 32 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. MC RENTON OCED - Basin Modeling 5/5/2026 11:06:03 AM Page 33 Appendix Predeveloped Schematic MC RENTON OCED - Basin Modeling 5/5/2026 11:06:03 AM Page 34 Mitigated Schematic MC RENTON OCED - Basin Modeling 5/5/2026 11:06:04 AM Page 35 Predeveloped UCI File MC RENTON OCED - Basin Modeling 5/5/2026 11:06:04 AM Page 36 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 MC RENTON OCED - Basin Modeling.wdm MESSU 25 MitMC RENTON OCED - Basin Modeling.MES 27 MitMC RENTON OCED - Basin Modeling.L61 28 MitMC RENTON OCED - Basin Modeling.L62 30 POCMC RENTON OCED - Basin Modeling1.dat 31 POCMC RENTON OCED - Basin Modeling2.dat 32 POCMC RENTON OCED - Basin Modeling3.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 7 IMPLND 8 COPY 501 COPY 502 COPY 503 DISPLY 1 DISPLY 2 DISPLY 3 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Drainage Basin 1 (PURPLE) MAX 1 2 30 9 2 Drainage Basin 2 (BLUE) MAX 1 2 31 9 3 Drainage Basin 3 (BYPASS, MAX 1 2 32 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 502 1 1 503 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 *** 7 A/B, Lawn, Flat 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY MC RENTON OCED - Basin Modeling 5/5/2026 11:06:04 AM Page 37 <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 7 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 ********* 7 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 *** 7 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 7 0 5 0.8 400 0.05 0.3 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 7 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 7 0.1 0.5 0.25 0 0.7 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 7 0 0 0 0 3 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 8 SIDEWALKS/FLAT 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 8 0 0 1 0 0 0 END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 8 0 0 4 0 0 4 1 9 END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** 8 0 0 0 0 0 END IWAT-PARM1 MC RENTON OCED - Basin Modeling 5/5/2026 11:06:04 AM Page 38 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 8 400 0.01 0.1 0.1 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 8 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 8 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Drainage Basin 1 (PURPLE)*** PERLND 7 0.015 COPY 501 12 PERLND 7 0.015 COPY 501 13 IMPLND 8 0.679 COPY 501 15 Drainage Basin 2 (BLUE)*** PERLND 7 0.245 COPY 502 12 PERLND 7 0.245 COPY 502 13 IMPLND 8 0.835 COPY 502 15 Drainage Basin 3 (BYPASS, ORANGE)*** PERLND 7 0.085 COPY 503 12 PERLND 7 0.085 COPY 503 13 IMPLND 8 0.093 COPY 503 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 COPY 502 OUTPUT MEAN 1 1 48.4 DISPLY 2 INPUT TIMSER 1 COPY 503 OUTPUT MEAN 1 1 48.4 DISPLY 3 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 MC RENTON OCED - Basin Modeling 5/5/2026 11:06:04 AM Page 39 HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1 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 COPY 2 OUTPUT MEAN 1 1 48.4 WDM 702 FLOW ENGL REPL COPY 502 OUTPUT MEAN 1 1 48.4 WDM 802 FLOW ENGL REPL COPY 3 OUTPUT MEAN 1 1 48.4 WDM 703 FLOW ENGL REPL COPY 503 OUTPUT MEAN 1 1 48.4 WDM 803 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 MC RENTON OCED - Basin Modeling 5/5/2026 11:06:04 AM Page 40 Predeveloped HSPF Message File MC RENTON OCED - Basin Modeling 5/5/2026 11:06:04 AM Page 41 Mitigated HSPF Message File MC RENTON OCED - Basin Modeling 5/5/2026 11:06:04 AM Page 42 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. 2005-2026; 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 E Drainage Basin Maps MULTICARE RENTON OCEDDESIGNED BY: DATE: PROJECT NO: DRAWN BY: CHECKED BY: 10182600015 640 Woodland Square Loop, Suite 100 Lacey, WA 98503 360.292.7230 www.kpff.com EXHIBIT SURFACE AREAS TABULATION 1BAL KK KK 04-29-2026 NOTES: 1.SURFACE AREAS DOES NOT INCLUDE RENOVATION/ REPLACEMENT OF EXISTING BUILDING (±17,073 SF). SCALE 0 20 40 LEGEND RIGHT-OF-WAY PROPERTY LINE REPLACED IMPERVIOUS SURFACE NEW IMPERVIOUS SURFACE REPLACED PERVIOUS SURFACE NEW PERVIOUS SURFACE (IN AREAS OF EXISTING HARDSCAPE) SURFACE AREA TABULATION TYPE AREA (SF) REPLACED IMPERVIOUS SURFACES 17,157 NEW IMPERVIOUS SURFACES 399 TOTAL NEW & REPLACED IMPERVIOUS 17,556 REPLACED PERVIOUS SURFACES 181 NEW PERVIOUS SURFACES 1,835 TOTAL NEW & REPLACED PERVIOUS 2,016 TOTAL DISTURBANCE:19,572 REPLACED IMPERVIOUS SURFACES (TYP) NEW PERVIOUS SURFACES (TYP) NEW IMPERVIOUS SURFACES (TYP) REPLACED PERVIOUS SURFACES (TYP) MULTICARE RENTON OCEDDESIGNED BY: DATE: PROJECT NO: DRAWN BY: CHECKED BY: 10182600015 640 Woodland Square Loop, Suite 100 Lacey, WA 98503 360.292.7230 www.kpff.com EXHIBIT EXISTING DRAINAGE BASIN AREAS 2BAL KK KK 04-29-2026 SCALE 0 20 40 LEGEND RIGHT-OF-WAY PROPERTY LINE DRAINAGE BASIN 1 DRAINAGE BASIN 2 DRAINAGE BASIN 3 (BYPASS) EXISTING DRAINAGE BASIN AREA TABULATION TYPE AREA (SF)AREA (AC) BASIN 1 30,237 0.694 TOTAL IMPERVIOUS AREA 29,603 0.680 TOTAL PERVIOUS AREA 634 0.014 BASIN 2 47,032 1.080 TOTAL IMPERVIOUS AREA 37,834 0.869 TOTAL PERVIOUS AREA 9,198 0.211 BASIN 3 7,734 0.178 TOTAL IMPERVIOUS AREA 4,046 0.093 TOTAL PERVIOUS AREA 3,688 0.085 DRAINAGE BASIN 1 AREA = 30,237 SF IMPERVIOUS AREA = 29,603 SF PERVIOUS AREA = 634 SF DRAINAGE BASIN 2 AREA = 47,032 SF IMPERVIOUS AREA = 37,834 SF PERVIOUS AREA = 9,198 SF DRAINAGE BASIN 3 (BYPASS) AREA = 7,734 SF IMPERVIOUS AREA = 4,046 SF PERVIOUS AREA = 3,688 SF MULTICARE RENTON OCEDDESIGNED BY: DATE: PROJECT NO: DRAWN BY: CHECKED BY: 10182600015 640 Woodland Square Loop, Suite 100 Lacey, WA 98503 360.292.7230 www.kpff.com EXHIBIT PROJECT DRAINAGE BASIN AREAS 3BAL KK KK 04-29-2026 SCALE 0 20 40 LEGEND RIGHT-OF-WAY PROPERTY LINE REPLACED IMPERVIOUS SURFACE NEW IMPERVIOUS SURFACE REPLACED PERVIOUS SURFACE NEW PERVIOUS SURFACE (IN AREAS OF EXISTING HARDSCAPE) DRAINAGE BASIN 1 DRAINAGE BASIN 2 DRAINAGE BASIN 3 (BYPASS) OFF SITE DRAINAGE BASIN AREAS DRAINAGE BASIN AREAS TABULATION TYPE AREA (SF)AREA (AC) BASIN 1 (ON-SITE)28,846 0.662 NEW & REPLACED IMPERVIOUS 6,673 0.153 TOTAL IMPERVIOUS 28,206 0.648 NEW & REPLACED PERVIOUS 177 0.004 TOTAL PERVIOUS 640 0.014 BASIN 1 (OFF-SITE)1,391 0.032 NEW & REPLACED IMPERVIOUS 0 0 TOTAL IMPERVIOUS 1,391 0.032 NEW & REPLACED PERVIOUS 0 0 TOTAL PERVIOUS 0 0 BASIN 1 (TOTAL)30,237 0.694 BASIN 2 (ON-SITE)39,901 0.916 NEW & REPLACED IMPERVIOUS 10,803 0.248 TOTAL IMPERVIOUS 31,900 0.732 NEW & REPLACED PERVIOUS 1,839 0.042 TOTAL PERVIOUS 8,001 0.184 BASIN 2 (OFF-SITE)7,131 0.164 NEW & REPLACED IMPERVIOUS 80 0.002 TOTAL IMPERVIOUS 4,505 0.103 NEW & REPLACED PERVIOUS 0 0 TOTAL PERVIOUS 2,626 0.061 BASIN 2 (TOTAL)47,032 1.080 BASIN 3 (ON-SITE)7,734 0.178 NEW & REPLACED IMPERVIOUS 0 0 TOTAL IMPERVIOUS 4,046 0.093 NEW & REPLACED PERVIOUS 0 0 TOTAL PERVIOUS 3,688 0.085 BASIN 3 (OFF-SITE)0 0 NEW & REPLACED IMPERVIOUS 0 0 TOTAL IMPERVIOUS 0 0 NEW & REPLACED PERVIOUS 0 0 TOTAL PERVIOUS 0 0 BASIN 3 (TOTAL)7,734 0.178 REPLACED IMPERVIOUS SURFACES (TYP) NEW PERVIOUS SURFACES (TYP) NEW IMPERVIOUS SURFACES (TYP) REPLACED PERVIOUS SURFACES (TYP) DRAINAGE BASIN 1 AREA = 30,237 SF IMPERVIOUS AREA = 29,597 SF PERVIOUS AREA = 640 SF DRAINAGE BASIN 2 AREA = 47,032 SF IMPERVIOUS AREA = 36,405 SF PERVIOUS AREA = 10,627 SF DRAINAGE BASIN 3 (BYPASS) AREA = 7,734 SF IMPERVIOUS AREA = 4,046 SF PERVIOUS AREA = 3,688 SF REPLACED IMPERVIOUS SURFACES OFF SITE (TYP) APPENDIX F CSWPPP (Forthcoming) APPENDIX G Stormwater Operations and Maintenance Manual (Forthcoming) APPENDIX H Off-site Analysis Drainage System Table CITY OF RENTON SURFACE WATER DESIGN MANUAL 2022 City of Renton Surface Water Design Manual 6/22/2022 Ref 8-B-1 REFERENCE 8-B OFF-SITE ANALYSIS DRAINAGE SYSTEM TABLE CITY OF RENTON SURFACE WATER DESIGN MANUAL, CORE REQUIREMENT #2 Basin: Subbasin Name: Subbasin Number: Date Symbol Drainage Component Type, Name, and Size Drainage Component Description Slope Distance from Site Discharge Existing Problems Potential Problems Observations of Field Inspector, Resource Reviewer, or Resident See map Type: sheet flow, swale, stream, channel, pipe, pond, flow control/ treatment/on-site BMP/facility Size: diameter, surface area drainage basin, vegetation, cover, depth, type of sensitive area, volume % ¼ ml = 1,320 ft. Constrictions, under capacity, ponding, overtopping, flooding, habitat or organism destruction, scouring, bank sloughing, sedimentation, incision, other erosion Tributary area, likelihood of problem, overflow pathways, potential impacts East Lake Washington Johns Creek 339 4/10/2026 12"-36" conveyance piping mainly developed varies 0 miles to 1 mile None known None anticipated New problems = very unlikely