Loading...
HomeMy WebLinkAboutTIR-3988DEVELOPMENT ENGINEERING Justin Johnson 04/18/2018 SURFACE WATER UTILITY rstraka 04/19/2018 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 1 Section Page EXECUTIVE SUMMARY ........................................................................................................................................... 2 SECTION 1 - PROJECT OVERVIEW ........................................................................................................................... 4 DRAINAGE BASINS, SUBBASINS, AND SITE CHARACTERISTICS ................................................................................................ 11 SOILS ......................................................................................................................................................................... 12 SECTION 2 - CONDITIONS AND REQUIREMENTS SUMMARY ................................................................................ 14 SECTION 3 - OFF-SITE ANALYSIS ........................................................................................................................... 18 SECTION 4 - FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN ......................................... 21 HYDROLOGIC ANALYSIS ................................................................................................................................................. 21 EXISTING SITE HYDROLOGY ............................................................................................................................................ 21 DEVELOPED SITE HYDROLOGY ........................................................................................................................................ 22 FLOW CONTROL ANALYSIS ............................................................................................................................................. 22 ON-SITE STORMWATER BMPS ....................................................................................................................................... 23 WATER QUALITY SYSTEM .............................................................................................................................................. 24 SUMMARY .................................................................................................................................................................. 25 SECTION 5 - CONVEYANCE SYSTEM ANALYSIS AND DESIGN ................................................................................. 26 CONVEYANCE .............................................................................................................................................................. 26 100-YEAR FLOOD/OVERFLOW CONDITION ....................................................................................................................... 26 SECTION 6 - SPECIAL REPORTS AND STUDIES ....................................................................................................... 27 SECTION 7 - OTHER PERMITS ............................................................................................................................... 28 SECTION 8 - CSWPPP ANALYSIS AND DESIGN ....................................................................................................... 29 SECTION 9 - BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT ............................... 31 SECTION 10 - OPERATIONS AND MAINTENANCE MANUAL .................................................................................. 32 APPENDICES: A – EXHIBITS B – PLANS C – DESIGN CALCULATIONS D – OPERATIONS AND MAINTENANCE MANUAL E – WATER QUALITY DEPARTMENT OF ECOLOGY CERTIFICATION F – GEOTECHNICAL REPORTS G – BOND QUANTITY WORKSHEET H – DECLARATION OF COVENANT AND FACILITY SUMMARY Table of Contents Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 2 The project property is located at 17816 108th Ave SE in Renton, Washington. The site is bordered by 108th Ave SE/WA 515 to the west, a vacant restaurant building to the north, a restaurant to the south, and 109th Ave SE to the east. The site is currently developed as vacant commercial retail building, which has a footprint of 3,095 square feet, with associated parking and landscaping. The entire lot is approximately 0.90 acres in size (after ROW dedication the parcel is 0.85 acres). This project proposes to demolish the existing building and parking lot and redevelop the site to become a dental office. The project site lies within the Lower Green River Subwatershed, which is part of the Green/Duwamish Watershed. It is in the City of Renton Black River drainage basin. The project site is located in the City of Renton Commercial Mixed-Use Overlay District (Community Planning area). The property is zoned CA (Commercial Arterial). Design Criteria: The City of Renton has adopted the 2017 Renton Surface Water Design Manual (RSWDM) for the design of stormwater facilities. The existing site is developed and primarily impervious with the exception of landscape islands and an undeveloped piece of land between the parking lot and 109th Ave SE. The proposed development will lead to a slight increase in the amount of overall impervious area. Per the requirements of RSWDM, both flow control and water quality mitigation will be required as a result of the proposed development. Table 1 Jurisdictional Requirements Peak Runoff Control: Flow Control Duration Standard Matching Forested Site Conditions Matching durations from 50% of 2- year flow up to full 50-year events, and peak flow rates for the 2-year and 10-year runoff events Water Quality: Enhanced Basic WQ Treatment Preceding detention 72% of the 2-year peak flow rate Downstream of detention The full 2-year release rate from detention facility On-Site BMPs: Application of BMPs to the maximum extent feasible Executive Summary Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 3 Proposed Drainage System: This project proposes to utilize StormTech arch chamber system, as allowed per RSWDM section 5.2.6, for flow control/infiltration and modular wetland system for water quality treatment. The proposed grading will generally convey surface water runoff via sheet flow from the east side of the site toward the west side of the site. Stormwater will be collected within catch basins strategically placed at low points along the east and south side of the building within the parking area. Once collected within the catch basins the stormwater will be conveyed via underground piping to the southwest corner of the site to the stormwater treatment structure. After treatment, stormwater will be conveyed to the detention/infiltration system which in conjunction with a flow control structure, will provide flow control as required by the jurisdictional requirements identified in Table 1. After detention, stormwater will be released to the existing City stormwater system in 108th Ave. SE. Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 4 Figure 1 - TIR Worksheet (2017 COR SWDM) Section 1 - Project Overview Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 5 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 6 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 7 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 8 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 9 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 10 Site Location: Figure 2 - Site Location Location: 17816 108th Ave SE, Renton, WA 98055 Section/Township/Range: NE Quarter of Section 32, Township 23, Range 05 Parcel/Tax Lot(s): 3223059054 Size: 0.90 acres (0.85 acres after ROW dedication along 109th Ave. SE) City, County, State: Renton, King County, Washington Governing Agency: City of Renton Design Criteria: 2017 City of Renton Surface Water Design Manual (RSWDM) Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 11 Drainage Basins, Subbasins, and Site Characteristics Drainage Basin The project site is located in the Lower Green River Subwatershed, which is part of the Green/Duwamish Watershed. It is in the City of Renton Black River drainage basin. Existing Sub-basins The existing site consists of a single basin with an area of 0.90 acres. The northeast portion of the site of the highest in elevation at 410’, and the area gradually slopes west toward the building, which has a finished floor elevation of approximately 405.5’. The east side of the site starts at an elevation of 411’ and slopes downward toward the southwest corner of the site where it has an elevation of 400’. Runoff is collected at a catch basin on the west side of the property, where it is then conveyed into the municipal stormwater system. Refer to Section 3 for existing discharge points to and from the site. Proposed Sub-basins The proposed storm drainage system will be comprised of one sub-basin. The sub-basin is about 0.85 acres in size (proposed sub-basin has been reduced in size due to ROW dedication along 109th Ave SE). Stormwater sheet flows generally from east to west and is collected within catch basins strategically placed at low points along the east and south side of the proposed building within the parking area. Runoff is then conveyed via underground pipes to the modular wetland water quality treatment system. After treatment, stormwater will enter the open bottomed arch chamber system for detention/infiltration. Stormwater is then conveyed through a flow control device and discharges into the municipal system on 108th Ave SE. See Appendix B for plans showing the distance from the farthest upstream end to the nearest proposed flow control facility. Table 2 – Site Areas Surface Existing Area (AC) Proposed Area (AC) Roof 0.07 0.22 Landscaping (Pervious) 0.36 0.25 Pavement (PGIS) 0.44 0.36 Sidewalk (NPGIS) 0.03 0.02 Total 0.90 0.85* *Total acreage has been reduced due to ROW dedications Site Characteristics The project property is located at 17816 108th Ave. SE in Renton, Washington. The site is bordered by 108th Ave. SE/WA 515 to the west, a vacant commercial building to the north, a Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 12 restaurant to the south, and 109th Ave .SE to the east. There is also a residential property to the NE as well. The site is currently developed as vacant commercial retail building, which has a footprint of 3,095 square feet, with associated parking and landscaping. The entire lot is approximately 0.90 acres in size. This project proposes to demolish the existing restaurant and parking lot, then redevelop the site to become dental office space. Right-of-way dedications are required along both the 108th Ave. SE and 109th Ave. SE frontages. The proposed project will include the construction of an approximately 7,800 SF Dentist office building along with associated parking, drive aisles, sidewalks, site amenities, utilities, stormwater facilities, and landscaping. Soils Websoil Survey Figure 3a - Site Soils (USDA Web Soil Survey Map) The site is mapped as Alderwood gravelly sandy loam 0 to 8 percent slopes (AgB) and Alderwood gravelly sandy loam 8 to 15 percent slopes (AgC) according to the USDA Natural Resource Conservation Service, Web Soil Survey for King County Area, Washington. Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 13 Figure 3b - Downstream Site Soils (USDA Web Soil Survey Map) The downstream area is mapped as Alderwood gravelly sandy loam 0 to 8 percent slopes (AgB), Alderwood gravelly sandy loam 8 to 15 percent slopes (AgC), and Arents 6 to 15 percent slopes according to the USDA Natural Resource Conservation Service, Web Soil Survey for King County Area, Washington. Geotechnical Report The following information was gathered from a report created by Geotech Consultants, Inc. on April 11, 2017. At a depth of 4 feet below the surface, testing indicated that soil was composed of gravelly silty sand fill overlying native, medium dense, silty sand. Underneath this soil was very dense silty sand. The bottom of the infiltration test was at 15.9 feet. Perched groundwater seepage was observed during the infiltration test at depths of 2.5 to 3.5 feet. The seepage levels on the logs represent the location of transient water seepage and may not indicate the static groundwater level. The allowable bearing pressure of the soil was determined to be 2,500 pounds per square foot. An infiltration test was performed on the site on January 11, 2018. Although the infiltration testing yielded results comparable to the assumed infiltration rates, the geotechnical engineer who prepared the report recommended that infiltration not be utilized. Therefore, no infiltration will be utilized in the design. Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 14 As required by the 2017 City of Renton Surface Water Design Manual (SWDM) this project is subject to a full drainage review. Therefore, the storm drainage design for this project is required to comply with all nine (9) Core Requirements, and six (6) Special Requirements. The requirements have been met as follows: Core Requirement #1: Discharge at Natural Location All surface and storm water runoff from a project must be discharged at the natural location so as not to be diverted onto or away from downstream properties. The manner in which runoff is discharged from the project site must not create a significant adverse impact to downhill properties or drainage systems. Response: Onsite runoff will be collected, conveyed, and when necessary, treated. All onsite runoff is subsequently conveyed to the City of Renton stormwater system. The city system discharges northwest of the site into Panther Creek. No downstream impacts are anticipated as a result of the proposed improvements as the impervious area will remain approximately the same. Core Requirement #2: Off-site Analysis All proposed projects must submit an offsite analysis report that assesses potential offsite drainage and water quality impacts associated with development of the project site and propose appropriate mitigation of those impacts. The initial permit submittal shall include, at minimum, a Level 1 downstream analysis. Response: See Section 3 of this report for a complete off-site analysis. Core Requirement #3: Flow Control All proposed projects, including redevelopment projects, must provide onsite flow control facilities or flow control BMPs or both to mitigate the impacts of storm and surface runoff generated by new impervious surface, new pervious surface, and replaced impervious surface targeted for flow mitigation. Response: Per City of Renton SWDM, flow control will be provided for Flow Control Duration Standard Matching Forested Site Conditions. A stormwater detention system and flow control structure will be put in place to match pre-development conditions for 50% of the 2-year up to the full 50-year design storm event and also the 2-year and 10-year peak flows. A detailed summary and analysis of the existing and proposed conditions is provided in Section 4 of this report. Section 2 - Conditions and Requirements Summary Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 15 Core Requirement #4: Conveyance System All engineered conveyance system elements for proposed projects must be analyzed, designed, and constructed to provide a minimum level of protection against overtopping, flooding, erosion, and structural failure. Response: The proposed conveyance system has been designed to convey the 25-year peak flow, as any overtopping experienced caused by a 100-year peak flow would not create either a severe flooding or severe erosion problem. See Section 5 – Conveyance System and Design for details. Core Requirement #5: Erosion and Sediment Control All proposed projects that will clear, grade, or otherwise disturb the site must provide erosion and sediment controls to prevent, to the maximum extent practicable, the transport of sediment from the project site to downstream drainage facilities, water resources, and adjacent properties. Both temporary and permanent ESC measures shall be implemented. Response: Erosion and sediment control requirements will be an integral part of the project construction documents. These measures will include methods to reduce erosion of onsite site soils and to prevent sediments from inadvertently leaving the project site. Additionally, the ESC measures will prevent sediment-laden discharge from entering the existing stormwater water facilities. Core Requirement #6: Maintenance and Operations Maintenance and operation of all drainage facilities is the responsibility of the property owner, except those facilities for which the City of Renton assumes maintenance and operation, and must be maintained and operated in accordance with King County or other maintenance standards as approved by the City of Renton. Response: An Operations and Maintenance Manual is included in this report – see Section 10. Core Requirement #7: Financial Guarantees and Liability In accordance with RMC 4-6-030J, RDSD shall require all persons constructing any surface water facilities (including flow control/water quality facilities, conveyance systems, erosion control, and road drainage), to post with the City of Renton a bond, assignment of funds or certified check. The applicant must also maintain liability insurance. Response: See Section 9 - Bond Quantities, Facility Summaries, and Declaration of Covenant. The Site Improvement Bond Quantity Worksheet and Declarations of Covenants are included as appendices in this report. Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 16 Core Requirement #8: Water Quality All proposed projects, including redevelopment projects, must provide water quality (WQ) facilities to treat the runoff from those new and replaced pollution-generating impervious surfaces and new pollution-generating pervious surfaces targeted for treatment. Response: Enhanced Basic Treatment is required, as more than 50% of the runoff that drains to the proposed treatment facility is from commercial land use. The proposed project will provide enhanced water quality treatment through the implementation of a Modular Wetland System. A detailed summary and analysis of the water quality basin and design is provided in Section 4 of this report. Core Requirement #9: On-Site BMPs All proposed projects, including redevelopment projects, must provide on-site BMPs to mitigate impacts of storm and surface water runoff generated by new impervious surface, new pervious surface, existing impervious surfaces, and replaced impervious surface targeted for mitigation as specified in the following sections. On-site BMPs include, but are not limited to, preservation and use of native vegetated surfaces to fully disperse runoff; use of other pervious surfaces to disperse runoff; roof downspout infiltration; permeable pavements; bioretention; limited infiltration systems; and reduction of development footprint. Response: On-site BMPs are required to be evaluated for this site. Per the City of Renton SWDM, Section 1.2.9.2.2 Large Lot BMP Requirements, on-site BMPs must be applied as specified in the requirements OR the project must demonstrate compliance with the LID performance standard. Due to infeasibility of other BMPs, the only available BMPs that are applicable are tree retention and the use of amended soils for proposed non-impervious areas. Special Requirement #1: Other Adopted Area-Specific Requirements The City of Renton may apply requirements for controlling drainage on an area-specific basis. Potential other adopted area-specific requirements may include: Master Drainage Plans, Basin Plans, Stormwater Compliance Plans, etc. Response: The project site is within Washington State Water Resource Inventory Area 9: Green/Duwamish and Central Puget Sound Watershed Salmon Habitat Recovery. However, the proposed project will have no effect on any salmon habitats. The project site does not lie within any City of Renton Master Drainage or Basin Plans. Special Requirement #2: Flood Hazard Area Delineation If a proposed project contains or is adjacent to a flood hazard area as determined by the Renton Department of Storm Drainage, the project must determine those components that are applicable and delineate them on the project’s site improvement plans and recorded maps. Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 17 Response: The project site does not lie within or adjacent to a City of Renton Flood Hazard Area (determined by FEMA FIRM Panel 53033C0979F dated May 16, 1995) and therefore does not need to apply the provisions of this requirement. Special Requirement #3: Flood Protection Facilities Proper analysis, design, and construction are necessary to protect against the potentially catastrophic consequences if flood protection facilities such as levees and revetments should fail. Response: The proposed project will not rely on an existing flood protection facility or modify or construct a new flood protection facility. Special Requirement #4: Source Control If a proposed project requires a commercial building or commercial site development permit, then the water quality source controls applicable to the proposed project shall be applied in accordance with the King County Stormwater Pollution Prevention Manual and Renton Municipal Code IV. Response: Water quality source controls will be applied in accordance with the RSWDM and Renton Municipal Code IV. A pollution prevention plan has been included in Section 8 of this report. Special Requirement #5: Oil Control Projects proposing to develop or redevelop a high-use site must provide oil control in addition to other water quality controls required. Response: High-use sites area defined as a commercial or industrial site that (1) has an expected average daily traffic count equal to or greater than 100 vehicles/1,000 SF of gross building area: (2) is subject to petroleum storage in excess of 1,500 gallons per year; (3) is subject to use, storage, or maintenance of a fleet of 25 or more diesel vehicles. The proposed development does not exceed any of these thresholds and is therefore not required to provide oil control. Special Requirement #6: Aquifer Protection Area If a proposed project is located within the Aquifer Protection Area as identified in the RMC 4-3- 050, this special requirement requires the project to determine those components that are applicable and delineate them on the project’s site improvement plans. Response: The project is not located within an Aquifer Protection Area, and therefore this requirement does not apply. Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 18 Upstream Analysis Due to the existing topography minimal tributary area drains to the site. Stormwater runoff within the ROW sheet flows to the curb and gutters where it is then collected within catch basins and conveyed via underground pipes. Downstream Analysis After the runoff passes through the proposed stormwater detention/treatment facilities, runoff enters the municipal stormwater system along 108th Ave SE. After crossing over 108th Ave SE, the system travels northwest about 2,500 feet through the Fred Meyer development and then crosses SE Carr Rd where it then discharges into Panther Creek. A map of the downstream analysis can be seen in Figure 4. Figure 4 - Downstream Area (Renton COR Maps) Section 3 - Off-Site Analysis DISCHARGE POINT PROJECT SITE POINT OF ENTRY TO CITY OF RENTON STORM SYSTEM PANTHER CREEK Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 19 Resource Review The following resources were reviewed in preparing an offsite analysis: · FEMA flood maps · Sensitive areas maps (King County DDES) · King County Soils Survey (USDA) · Wetlands Inventory (RDSD) · Section 303d list of polluted waters (WSDOE) · City of Renton Erosion and Landslide Maps Field Inspection The downstream system ¼ mile from the site is entirely within subsurface piping, therefore it is not feasible for the design engineer to physically perform a field inspection. A resource review was performed in order to fulfill the following field inspection requirements: 1. There were not any issues found during the resource review. 2. There are no anticipated constrictions or lack of capacity in the existing drainage system. 3. Problem Type 1 - There are no anticipated failures of the conveyance system downstream from the project site. Problem Type 2 - After reviewing the City of Renton Erosion Hazard Map, neither the project site nor downstream area are within an erosion hazard area. Problem Type 3 - After reviewing the City of Renton Flood Hazard Map along with the FEMA flood map, there not any concerns regarding the potential of a severe building or roadway flooding problem. 4. There is no anticipated or existing overtopping, scouring bank sloughing, or sedimentation problems because the site is not within a flood or erosion hazard area. 5. After reviewing the Wetlands Inventory, there is no anticipated destruction of aquatic habitat or organisms because there are no major streams or lakes downstream of the project site. 6. The land uses of the project site, downstream area, and other businesses within the vicinity are primarily commercial. Impervious surfaces within the area include paving for 108th Ave SE, the proposed dentist office building, and the associated parking lot. See Section 1 for soil details. The topography of this project site and downstream is fairly flat. 7. There are no major streams or wetlands downstream of this project within ¼ mile. The project site and downstream area are not within a landslide hazard area or erosion hazard area. The storm drainage pipes downstream of the project site are 12” and 24”. 8. The tributary basin delineated in Task 1 are confirmed. 9. After the resource review, there are no concerning existing drainage problems. 10. N/A Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 20 Drainage System Description and Problem Descriptions See Figure 4 above for the location of the project site with respect to the discharge points. The downstream drainage system is comprised of 24” and 12” storm drain pipe running at approximately 0.5% slope. The land cover just downstream of the site is primarily impervious. There are no existing or anticipated problems because the site and downstream area are not in an erosion or flooding hazard area, steep slope hazard area, or wetland area. Mitigation of Existing or Potential Problems There is no necessary mitigation because there are no anticipated drainage issues downstream of the site. Conclusion: The proposed stormwater management system for this project has been designed in accordance with regulatory criteria described above and is consistent with sound engineering practice. The site has been analyzed to determine the requirements for detention and water quality treatment, and no significant adverse impacts to the stormwater management system are expected as a result of the proposed development. Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 21 The City of Renton 2017 SWDM applies flow control standards based on geographic areas as determined by the Flow Control Application Map. The project site lies within a Conservation Flow Control Area. This requires a level 1 downstream analysis. This area requires peak runoff control within the Flow Control Duration Standard Matching Forested Site Conditions area such that it matches the flow duration of predeveloped rates for the existing site conditions over the range of flows extending from 50% of 2-year up to the full 50-year flow. This matches the flow duration of predeveloped rates for the existing site conditions over the range of flows extending from 50% of 2-year up to the full 50-year flow and the 2-year and 10-year peak flows. Hydrologic Analysis The existing and proposed site conditions were evaluated using the Western Washington Hydrology Model (WWHM) The detailed WWHM output has been included in Appendix C. The historic 1-hour duration in the Sea-Tac rainfall region (location scale factor ST-1.0) was used to model runoff in WWHM. Existing Site Hydrology The existing site consists primarily of a single sub-basin. The site generally flows from east to west, ranging from an elevation of 410 in the northeast corner to 400 at the west property line. Catch basins collect runoff and convey it underground to the existing City of Renton municipal storm drainage system along 108th Ave. SE. The municipal stormwater system discharges to Panther Creek across SE Carr Rd. The existing topography prevents run-on from the adjacent properties to the north and south, therefore do not contribute to the site drainage sub-basin. The pre-developed (existing) conditions and historic peak runoff rates for the project site area are shown in Tables 4 and 5 below. An exhibit showing the existing conditions is provided in Appendix A. Existing peak runoff rates were determined using the WWHM modeling software and the calculations can be found in Appendix C. Table 4 Pre-Developed (Existing) Conditions Area Condition 0.44 AC Pavement (PGIS) 0.03 AC Sidewalk 0.36 AC Landscape 0.07 AC Roof *For WWHM analysis, a fully forested condition was assumed per City of Renton requirements. Section 4 - Flow Control and Water Quality Facility Analysis Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 22 Table 5 Historic Peak Runoff Rate Event Rate (cfs) 2-year 0.0250 10-year 0.0473 100-year 0.0657 Developed Site Hydrology The developed site will preserve the general configuration of the existing site, with runoff generally flowing from east to west, being collected in catch basins located throughout the site prior to being conveyed to a treatment structure and a detention facility, then released into the existing system in 108th Ave. SE. Therefore, existing drainage pattern and discharge locations will be maintained. The post-developed conditions and un-detained peak runoff rates for the entire basin area are shown in Tables 6 and 7 below. An exhibit showing the developed conditions is provided in Appendix A. The proposed grading and drainage plan is included in Appendix B. Developed peak runoff rates were determined using the WWHM modeling software and the calculations can be found in Appendix C. Table 6 Post-Developed Conditions Area Condition 0.36 AC Pavement (PGIS) 0.02 AC Sidewalk 0.25 AC Landscape 0.22 AC Roof Table 7 Developed Peak Runoff Rate (Unmitigated) Event Rate (cfs) 2-year 0.237 10-year 0.346 100-year 0.493 Flow Control Analysis The proposed project includes installation of a subsurface open-bottom modular detention system in order to meet the requirements associated with the Flow Control Duration Standard. Per the recommendations included in the Stormwater Infiltration Considerations included in Appendix F, infiltration has not been utilized. The total storage provided by the detention system is 11,983 cubic feet, which is in excess of the required volume of 11,456 cf. Discharges from the detention system are shown in Table 8. Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 23 Table 8 Mitigated Peak Runoff Rate Event Rate (cfs) 2-year 0.0171 10-year 0.0363 100-year 0.0752 A flow control structure (per City of Renton standard plan 237.00) will be installed downstream of detention to regulate discharge rates. The structure shall incorporate a flow control tee consisting of three orifices and a riser pipe. On-Site Stormwater BMPs Per City of Renton SWDM Section 1.2.9.2.2, the project is subject to the Large Lot High Impervious BMP Requirements since the lot is greater than 22,000 square feet. This section requires evaluation of multiple BMPs to provide flow control – evaluation of BMPs is provided below. Full Dispersion: A native vegetated flowpath of at least 100 feet is not available to utilize for full dispersion. Native vegetation on the site is also located at a higher elevation than the developed site, and as such cannot receive runoff from developed surfaces. Full Infiltration: Per the Stormwater Infiltration Considerations report included in Appendix F, infiltration is not recommended for this project due to limited infiltration rates and the presence of perched groundwater. Limited Infiltration: Per the Stormwater Infiltration Considerations report included in Appendix F, infiltration is not recommended for this project due to limited infiltration rates and the presence of perched groundwater. Bioretention: Bioretention is not suitable per the Geotech’s recommendation that infiltration not be used. Permeable Pavement: Permeable pavement is not suitable per the Geotech’s recommendation that infiltration not be used. Basic Dispersion: An appropriate vegetated flowpath is not available for basic dispersion. Soil Amendment: All surfaces disturbed during construction where impervious surfaces are not proposed are to receive soil amendment meeting the quality and implementation requirements identified in the City of Renton SWDM. Tree Retention: All existing trees to remain shall be protected during construction per the requirements identified in the City of Renton SWDM. Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 24 Water Quality System In order to provide enhanced basic treatment, as required by City of Renton SWDM, a modular wetland system will be installed upstream of detention. The modular wetland is intended to collect and treat runoff generated by the pollutant-generating impervious areas on the site, mimicking the treatment effects of a wetland by utilizing a combination of cartridges for pre- treatment and biofiltration. The modular wetland systems have been granted General Use Level Designation (GULD) by the Washington State Department of Ecology (DOE) for Basic, Enhanced, and Phosphorous treatment. The approval documentation has been included in Appendix E. Table 9 Water Quality Flow Rates and Facility Sizing Basin Water Quality Flow Rate (cfs) From WWHM MWS-L-4-6-V Treatment Flow Rate (cfs) A 0.06 0.07 As identified by Modular Wetlands (image provided above), the specified MWS-L-4-6 unit provides 32 square feet of media surface area. Per the stated loading rate of 1 gallon per minute (gpm) per square foot of media, a treatment flow rate can be calculated as such: 32 square feet x (1 gpm / 1 square foot) = 32 gpm = 0.07 cfs Pre-treatment for the unit is based upon a loading rate of 2.1 gpm/sf. Based upon a surface area of approximately 12.8 square feet, the pre-treatment flow rate yields: 12.8 x (2.1 gpm / 1 square foot) = 27 gpm = 0.06 cfs Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 25 Summary Flow Control Event Historic Flow Rate (cfs) Developed Flow Rate (cfs) Mitigated Flow Rate/Discharge (cfs) 2-year 0.0260 0.237 0.0171 10-year 0.0473 0.346 0.0363 100-year 0.0657 0.493 0.0752 Flow control provided by the detention system meets the requirements for the Flow Control Duration Standard (City of Renton 2017 SWDM, Section 1.2.3.1). Water Quality Water Quality Flow Rates and Facility Sizing Basin Design WQ Flow Rate (cfs) From WWHM MWS-L-4-6-V Treatment Flow Rate (cfs) A 0.06 0.07 Water quality provided by the modular wetland units meets the requirements for the Enhanced Basic Water Quality standard for treatment upstream of detention. Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 26 Conveyance Per the 2017 City of Renton Surface Water Design Manual, the on-site stormwater conveyance can be calculated based on gravity flow analysis of the piping network. Peak run-off associated with and up to a 25-year storm event has been determined to be adequate. Uniform flow analysis utilizing Manning’s equation, shown below, was employed with a Manning’s Roughness Coefficient (n) of 0.012. Manning’s equation - Q=n 49.1 xAxR2/3xS1/2 With: Q = Flow (CFS) n = Manning’s Roughness Coefficient (0.012) A = Flow Area (SF) R = Hydraulic Radius = Area /Wetted Perimeter (LF) S = Slope of the pipe (ft/ft) Based on the proposed basin areas and pipe sizes, the conveyance system is adequate for the 25-year storm event (as well as the 100-year event). Additionally, the overflow from a 100-year storm event will not create or aggravate a severe flooding problem or severe erosion problem. See Appendix C for conveyance design calculations. 100-Year Flood/Overflow Condition Review of the current FEMA FIRM maps (Panel 0979 F) indicates that the project site lies within the Zone X, which is determined to be outside of the 100-year flood plain. If the existing storm system were to experience a major storm event, the stormwater system would overflow and exit the site at the access drive along 108th Ave SE. The stormwater system for this project has been designed to address the storm events in accordance with design criteria described previously. In the event of a larger storm, it is unlikely that the system would fail. Based on a review of the site and immediate surroundings, the overflow of the stormwater conveyance system would allow surface water to sheet flow to the public storm system in 108th Ave SE. Section 5 - Conveyance System Analysis and Design Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 27 The following Special Reports and Studies were used or have been completed for this project: · Geotechnical Engineering Report - by Geotech Consultants, Inc., dated April 11, 2017 · FEMA FIRM Panels 0979F dated May 16, 1995 · Stormwater Infiltration Considerations Section 6 - Special Reports and Studies Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 28 The following governmental approvals or permits will likely be required for this project: · City of Renton SEPA Determination · City of Renton Site Plan Review · City of Renton Building Permit · City of Renton Construction Permit · City of Renton Demolition Permit These permits will require approval by the City of Renton Planning Division or the Department of Ecology. Section 7 - Other Permits Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 29 All erosion and sediment control measures shall be governed by the requirements of the City of Renton and the Washington State Department of Ecology. A temporary erosion and sedimentation control plan will be prepared to assist the contractor in complying with these requirements. The Erosion and Sediment Control (ESC) plan will be included with the construction plans. 1. Erosion Risk Assessment The degree of erosion risk on the proposed project site is minimal. Slope across the site is minimal. Runoff will not travel at high velocities across the site and, therefore, will not cause noticeable erosion impacts. 2. Construction Sequence and Procedure The proposed development will include an erosion/sedimentation control plan designed to prevent sediment-laden run-off from leaving the site during construction. The erosion potential of the site is influenced by four major factors: soil characteristics, vegetative cover, topography, and climate. Erosion/sedimentation control is achieved by a combination of structural measures, cover measures, and construction practices that are tailored to fit the specific site. Prior to the start of any grading activity upon the site, all erosion control measures, including stabilized construction entrances, shall be installed in accordance with the construction documents. The best construction practice will be employed to properly clear and grade the site and to schedule construction activities. The planned construction sequence for the construction of the site is as follows: 1. Attend a pre-construction meeting with the City of Renton. 2. Install temporary erosion control features. 3. Demolish existing structure(s). 4. Clear and grub site. 5. Grade site. 6. Construct buildings. 7. Pave site and install landscaping. 8. Remove temporary erosion control features once site is fully stabilized. Section 8 - CSWPPP Analysis and Design Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 30 3. Trapping Sediment Structural control measures will be used to reduce erosion and retain sediment on the construction site. The control measures will be selected to fit specific site and seasonal conditions. The following structural items will be used to control erosion and sedimentation processes: · Stabilized construction entrances · Filter fabric fences · Catch Basin Inlet Sediment Protection · Proper Cover measures Weekly inspection of the erosion control measures will be required during construction. Any sediment buildup shall be removed and disposed of off-site. A stabilized construction entrance will be installed at the site entrance to avoid vehicle tracking off mud off-site. The entrances are a minimum requirement and may be supplemented if tracking of mud onto public streets becomes excessive. In the event that mud is tracked off site, it shall be swept up and disposed of off site on a daily basis. Depending on the amount of tracked mud, a vehicle road sweeper may be required. Because vegetative cover is the most important form of erosion control, construction practices must adhere to stringent cover requirements. More specifically, the contractor will not be allowed to leave soils open for more than 14 days and, in some cases, immediate seeding will be required. 4. Wet Season TESC Operating Plan Work between October 1st and April 30th must adhere to the Wet Season Special Provisions noted in the 2009 RSWDM. Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 31 See Appendix B for details of the proposed flow control and water quality facilities. See Appendix · Declaration of Covenant for Privately Maintained Flow Control BMPs · Bond Quantity Worksheet · Flow Control and Water Quality Facility Summary Section 9 - Bond Quantities, Facility Summaries, and Declaration of Covenant Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10573001 Page 32 A manual detailing the operations and maintenance for all privately-maintained flow control and water quality facilities has been prepared and can be found in Appendix D. Section 10 - Operations and Maintenance Manual Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Appendix A – Exhibits Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Appendix B – Plans Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Appendix C – Design Calculations Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Conveyance Design Calculations Manning’s equation: Q= xAxR 2/3xS1/2 With: Q = Flow (CFS) n = Manning’s Roughness Coefficient (0.012) A = Flow Area (SF) R = Hydraulic Radius = Area /Wetted Perimeter (LF) S = Slope of the pipe (ft/ft) 12” Pipe @ 0.5% slope: Q= xAxR 2/3xS1/2 = 2.94 CFS n = 0.012 A = 0.771 (SF) R = 0.286 @ 95% full S = 0.005 Pipe capacity exceeds 100-year peak flows generated by development. n 49.1 n 49.1 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Appendix D – Operations and Maintenance Manual Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Maintain Stormwater Facilities The owner or operator of the project shall be responsible for maintaining the stormwater facilities in accordance with local requirements. Proper maintenance is important for adequate functioning of the stormwater facilities. The following maintenance program is recommended for this project: Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Appendix E – Water Quality Department of Ecology Certification Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Appendix F – Geotechnical Reports Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Appendix G – Bond Quantity Worksheet Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Appendix H – Declaration of Covenant and Facility Summary Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003 Renton Dental Arts Technical Information Report Renton, Washington PACLAND Project #10507003