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APPROVED STM BLD2022-0989+Storm_Drainage_Report+8.15.2023_5.35.49_PM+3727874F- CC 0 a W W Q Z ry� jam==• V �� I e � P' DRAINAGE REPORT SUGAR HOUSE M6, -j►. August 2023 North Star Visions, LLC 19020 33rd Avenue West, Suite 450 PACE Lynnwood Washington 98036 An Engineering Services Company SUGAR HOUSE DRAINAGE REPORT Prepared For: North Star Visions, LLC 19020 33rd Avenue W. Suite 450 Lynnwood, Washington 98036 Cher Anderson October, 2022 Revised June 2023 Revised August 2023 Prepared By: CPACE- Tara L. Beitler, PE PACE Engineers, Inc. 3501 Colby Avenue, Suite 101 Everett, Washington 98201-4794 p. 425.486.6533 PACE Project No. 362-025-22 THIS PAGE IS INTENTIONALLY LEFT BLANK. PACE NORTH STAR VISIONS, LLC SUGAR HOUSE DRAINAGE REPORT AUGUST 2023 PROJECT CERTIFICATION The technical material and data contained in this report was prepared by PACE Engineers, Inc., under the supervision of the below listed individuals. Those responsible staff members who are registered professional engineers are licensed in the State of Washington. Tara ,gEE tJ � � IONAL, Tara Beitler, P.E. ned by Tara L. Beitler com, Inc.", 15 13:35:56-07'00' PACE Engineers, Inc. 3501 Colby Avenue, Suite 101 Everett, Washington 98201-4794 Phone: 425.486.6533 www.paceengrs.com PACE) PAGE NORTH STAR VISIONS, LLC SUGAR HOUSE DRAINAGE REPORT AUGUST 2023 THIS PAGE IS INTENTIONALLY LEFT BLANK. PAGE II �, PACE NORTH STAR VISIONS, LLC SUGAR HOUSE DRAINAGE REPORT AUGUST 2023 TABLE OF CONTENTS SECTION# TITLE PAGE # 1. Project Overview..............................................................................................................................4 2. Minimum Requirements.................................................................................................................. 6 2.1 Minimum Requirement #1: Preparation of Stormwater Site Plans....................................6 2.2 Minimum Requirement #2: Construction Stormwater Pollution Prevention .....................6 2.3 Minimum Requirement #3: Source Control of Pollution....................................................6 2.4 Minimum Requirement #4: Preservation of Natural Drainage Systems and Outfalls......... 6 2.5 Minimum Requirement #5: Onsite Stormwater Management .......................................... 6 3. Offsite Analysis................................................................................................................................. 7 3.1 Resource Review Summary.................................................................................................7 3.2 Upstream Basin Analysis.....................................................................................................7 3.3 Downstream Flowpath Analysis..........................................................................................7 4. Low Impact development and onsite stormwater management..................................................... 8 5. Other Permits............................................................................................................................... 10-9 LIST OF FIGURES VicinityMap...................................................................................................................................................5 APPENDICES APPENDIX A Resource Review Documents APPENDIX B Offsite Flow Paths APPENDIX C Site Maps APPENDIX D Calculations APPENDIX E Geotechnical Report PACE ) PAGE III NORTH STAR VISIONS, LLC SUGAR HOUSE DRAINAGE REPORT AUGUST 2023 1. PROJECT OVERVIEW North Star Visions proposes the development of a single family residential parcel on an existing undeveloped parcel totaling 0.22 acres along with the associated driveway and utilities. The property is located within the SW % of Section 36, Township 27 North, Range 3 East, W.M. More specifically, the project is located within Snohomish County, occupying Snohomish County Tax Parcel 00555000004902. The address is 10234 242"d PI SW, Edmonds, WA. The property is zoned RS-8. A vicinity map is provided on the following page to depict the project's location. The NRCS web soil survey identifies as urban land Alderwood soil units underlying the site. The Geotech Report dated August 22, 2022 prepared by Earth Solutions NW shows that the native soils are, "silty gravel with sand, poorly graded sand with silt and gravel, and poorly graded gravel with sand (USCS: GM, SP-SM and GP, respectively). The project is subject to the provisions of the City of Edmonds Municipal Code, the Addendum to Edmonds Community Development Code Chapter 18.30 (Edmonds Stormwater Addendum) dated June 30, 2022 (referred to as Addendum) and the 2019 Stormwater Management Manual for Western Washington (SWMMWW). The SWMMWW and Addendum specify several minimum stormwater management requirements that must be met for the project. A brief discussion of those requirements is provided in Section 2 of this report. Those requirements warranting further discussion are addressed in greater detail in later sections of this report. PAGE 4 �, PACE NORTH STAR VISIONs, LLC SUGAR HOUSE DRAINAGE REPORT AUGusT 2023 PACE PAGE 5 NORTH STAR VISIONS, LLC SUGAR HOUSE DRAINAGE REPORT AUGUST 2023 2. MINIMUM REQUIREMENTS The project is a new development which proposes less than 5,000 square feet of new/replaced hard surface area and is classified as a Category 1 project. Therefore it is required to satisfy five of the minimum requirements stipulated by the 2019 SWMMWW. 2.1 MINIMUM REQUIREMENT #1: PREPARATION OF STORMWATER SITE PLANS This report, along with the accompanying plans, is intended to satisfy the stormwater site plan requirements. This requirement includes research of applicable site information, evaluation of any upstream tributary drainage basins, and the downstream flowpath. These items are addressed in Section 3 of this report. 2.2 MINIMUM REQUIREMENT #2: CONSTRUCTION STORMWATER POLLUTION PREVENTION A stormwater pollution prevention plan (SWPPP) report will also be provided under separate cover. 2.3 MINIMUM REQUIREMENT #3: SOURCE CONTROL OF POLLUTION The project is not a high -use site and is not expected to have significant point -sources of pollution requiring source control methods. 2.4 MINIMUM REQUIREMENT #4: PRESERVATION OF NATURAL DRAINAGE SYSTEMS AND OUTFALLS The topography of the site generally slopes from the south to the north with slopes ranging from 3% to 20%. The site sheet flows to the north where the stormwater is collected in an existing piped stormwater system. 2.5 MINIMUM REQUIREMENT #5: ONSITE STORMWATER MANAGEMENT The project is required to either meet the low -impact flow control standard or evaluate a series of low -impact stormwater management features, as outlined in the SWMMWW. This project is electing to evaluate the low impact stormwater management features. Evaluation is provided in Section 4 of this report. PAGE 6 � PACE NORTH STAR VISIONs, LLC SUGAR HOUSE DRAINAGE REPORT AUGusT 2023 3. OFFSITE ANALYSIS This section of the report is intended to address Minimum Requirement #1, as outlined in the SWMMWW. 3.1 RESOURCE REVIEW SUMMARY The NRCS web soil survey identifies as urban land Alderwood soil units underlying the site. The Geotech Report dated August 22, 2022 prepared by Earth Solutions NW shows that the native soils are, "silty gravel with sand, poorly graded sand with silt and gravel, and poorly graded gravel with sand (USCS: GM, SP-SM and GP, respectively). Due to the existing steep slopes on the northwest corner the Geotechnical Engineer also recommends that there is no infiltration on the project. The Federal Emergency Management Agency (FEMA) identifies the project site on the Flood Insurance Rate Map (FIRM) panel #53061C1315F effective June 19, 2020, and is in Zone X. A FEMA map has been provided in Appendix A of this report for reference. The project is in Southwest Edmonds B watershed which conveys stormwater infiltration facilities. As the pipes don't connect into a waterway the 303d list was not consulted. See map provided in Appendix A of this report for reference. 3.2 UPSTREAM BASIN ANALYSIS There is a small area from the lot to the south (10229 244th St SW) that has a backyard that sheets flows onto the property. This area is considered negligible. It is assumed that the roof drains from the property will convey water to 244th Street 3.3 DOWNSTREAM FLOWPATH ANALYSIS The Downstream Exhibit in Appendix B shows the storm drain pipe from the City of Edmonds GIS Map. The project will connect into the existing 12" storm drain pipe on 242nd place SW that conveys water to the northwest. The 12" storm drain then go between lots 10314 and 10302 to the southwest, to the northwest and then to the southwest eventually entering the right-of-way on 104th Ave W. The 12" storm drain pipe conveys the runoff south for approximately 530 feet, then the pipes convey runoff to the west for approximately 215 feet where the pipe is then upsized to a 24" diameter pipe. PACE ) PAGE 7 NORTH STAR VISIONS, LLC SUGAR HOUSE DRAINAGE REPORT AUGUST 2023 4. LOW IMPACT DEVELOPMENT AND ONSITE STORMWATER MANAGEMENT The project is subject to minimum requirements #1-#5. Therefore, per Volume I Chapter 2.5.5, List 1 (Onsite Stormwater Management BMPs for Projects Triggering Minimum Requirements #1 through #5) was considered for the type of surface, with the requirement that the first BMP that is feasible must be used. The list and criteria are shown below. Lawn and Landscape Areas Post -Construction Soil Feasible —The project intends to strip the duff layer, stockpile it, Quality and Depth and re -use it on the completed site. (BMP T5.13) Full Dispersion Not Feasible — A 65 to 10 ratio of forested or native vegetation (BMP T5.30) or area to impervious area cannot be achieved. Downspout Fill Infiltration (BMP T5.30) Not Feasible -The project is located within 50 feet of the top of slopes greater than 15 percent (unless a geotechnical assessment and soils report is prepared addressing the potential impact of the proposed system). The geotechnical report does not recommend infiltration. Rain Gardens Not Feasible —Where professional geotechnical evaluation (BMP T5.14A) recommends infiltration not be used due to reasonable concerns about erosion, slope failure or downgradient flooding. Downspout Dispersion Not Feasible - For splashblocks, a vegetated flowpath at least 50 Systems feet in length from the downspout to the downstream property line, structure, stream, wetland, slope over 15 percent, or other impervious surface is not feasible Not Feasible - For trenches a vegetated flowpath of at least 25 feet in between the outlet of the trench and property lines, structure, stream , wetland or impervious surface is not feasible. A minimum vegetated flow path of at least 50 feet between the outlet of the trench and any slope steeper than 15 percent is not feasible Flow paths for adjacent dispersion devices cannot be sufficiently spaced to prevent overlap of flows in the flowpath areas. Perforated StubOut Not feasible —The connection would be within 50 feet of the top Connections of slopes greater than 15 percent. PAGE 8 �, PACE NORTH STAR VISIONs, LLC SUGAR HOUSE DRAINAGE REPORT AUGusT 2023 Detention Vaults/Pipes Feasible Other Hard Surfaces Full Dispersion Not Feasible —A 65 to 10 ratio of forested or native vegetation (BMP T5.30) area to impervious area cannot be achieved. Permeable Pavement Not Feasible —The geotechnical evaluation recommends (BMP T5.15) infiltration not be used due to reasonable concerns about erosion, slope failure, or downgradient flooding. Also it would be within 50 feet of the top of slopes greater than 15 percent. Rain Gardens Not Feasible —Where professional geotechnical evaluation (BMP recommends infiltration not be used due to reasonable concerns T5.14A)/Bioretention about erosion, slope failure or downgradient flooding. Sheet Flow Dispersion Feasible for the following case — Sheet flow dispersion will be (BMPs T5.11 / T5.12) used for the patio and sidewalk. Concentrated Flow Not Feasible — A minimum vegetated flowpath of 50 feet Dispersion between the discharge point and the top of slopes greater than15 percent is not feasible. Also the dispersion of runoff would create flooding or erosion impacts. Detention Vaults/Pipes Feasible - See the following page and Appendix C for the cross section and emails regarding the clearance issues. Note: The footing drains which are not anticipated to collect runoff will go to a drywell. The detention pipes or vaults must be installed for any site impervious surfaces totaling greater than or equal to 1,000 square feet. The project site has 4,393 square feet of impervious surface area. The detention system was sized to meet the requirements in the Edmonds Addendum. The requirements state: • Orifice size shall be 0.5 inches • For 36-Inch pipes: L = 0.008*A (where A is the contributing area in square feet) • L=0.008*4393 = 35.1 ft An overflow riser of 6" will have capacity. The following equation from Figure V-12.8: Riser Inflow Curves (located in Appendix D) was used: • Q100 = 0.102 cfs • H=(Q/(3.782D2))2 • H = Head in feet above the riser PACE PAGE 9 NORTH STAR VISIONS, LLC SUGAR HOUSE DRAINAGE REPORT AUGUST 2023 • Q100 = 100-year flow from MGSFlood (cfs) • D=diameter of riser (ft) • H=(0.102/(3.782*0.52))2 • H=0.01 ft (Minimum required is 05) Since the head in feet required to pass the 100-year flow is less than the minimum of 0.5' required the 6" overflow riser has capacity. S. OTHER PERMITS Building Permit will be required. PAGE 10 � PACE NORTH STAR VISIONS, LLC SUGAR HOUSE DRAINAGE REPORT AUGusT 2023 THIS PAGE IS INTENTIONALLY LEFT BLANK. PACE) PAGE 11 North Star Visions, LLC Sugar House Edmonds, WA Resource Review Documents PACE NORTH STAR VISIONS, LLC SUGAR HOUSE DRAINAGE REPORT AUGUST 2023 THIS PAGE IS INTENTIONALLY LEFT BLANK. PACE EDMONDS STORMWATER ADDENDUM JUNE 2017 Does the project result in 2,000 square feet, or greater, of new plus replaced hard surface area? OR Does the land disturbing activity total 7,000 square feet or greater? Yes No Minimum Requirements No. 1 through 5 apply I Minimum Requirement No. 2 applies Next Question Does the project add 5,000 square feet or more of new plus replaced hard surfaces? OR Convert 0.75 acres or more of vegetation to lawn or landscaped areas? OR Convert 2.5 acres or more of native vegetation to pasture? No Yes Yes Is this a road related project? All Minimum Requirements apply to the new and replaced Yes hard surfaces and converted �— vegetation areas. All Minimum Requirements apply to the new hard surfaces and converted vegetation areas. Does the project add 5,000 square feet or more of new hard surfaces? Yes Do new hard surfaces add 50% or more to the existing hard surfaces within the project limits? No Figure 3.1. Flow Chart for Determining Requirements for Development. No !gin No additional requirements. 8 3. APPLICABILITY OF THE MINIMUM REQUIREMENTS National Flood Hazard Layer FIRMette .. FEMA 122o22'32"W 47o46'57"N - I .07000 0 250 500 1,000 1,500 2,000 Basemap: USGS National Map: Orthoimagery. Data refreshed October, 2020 Legend SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT Without Base Flood Elevation (BFE) Zone A, V, A99 SPECIAL FLOOD With BFE or Depth Zone AE, AO, AH, Ve, AR HAZARD AREAS Regulatory Floodway 0.2% Annual Chance Flood Hazard, Areas of 1% annual chance flood with average depth less than one foot or with drainage areas of less than one square mile zonex Future Conditions 1% Annual Chance Flood Hazard Zone Area with Reduced Flood Risk due to OTHER AREAS OF Levee. See Notes. zone FLOOD HAZARD I " Area with Flood Risk due to Leveezone D NOSCREEN Area of Minimal Flood Hazard zonex Q Effective LOMRs OTHER AREAS Area of Undetermined Flood Hazard zone D GENERAL - — - - Channel, Culvert, or Storm Sewer STRUCTURES IIIIIII Levee, Dike, or Floodwall Cross Sections with 1%Annual Chance j7•5 Water Surface Elevation e - - - Coastal Transect -5is^^M^- Base Flood Elevation Line (BFE) Limit of Study Jurisdiction Boundary — --- Coastal Transect Baseline OTHER _ Profile Baseline FEATURES Hydrographic Feature Digital Data Available N No Digital Data Available MAP PANELS Unmapped " The pin displayed on the map is an approximate point selected by the user and does not represent an authoritative property location. This map complies with FEMA's standards for the use of digital flood maps if it is not void as described below. The basemap shown complies with FEMA's basemap accuracy standards The flood hazard information is derived directly from the authoritative NFHL web services provided by FEMA. This map was exported on 9/16/2022 at 3:50 PM and does not reflect changes or amendments subsequent to this date and time. The NFHL and effective information may change or become superseded by new data over time. This map image is void if the one or more of the following map elements do not appear: basemap imagery, flood zone labels, legend, scale bar, map creation date, community identifiers, FIRM panel number, and FIRM effective date. Map images for unmapped and unmodernized areas cannot be used for regulatory purposes. 547080 47' 46 47" N 2n bi 47' 46 40" N 547100 547129 547140 547160 547180 Map Scale: 1:1,080 if printed on A portrait (8.5" x 11") sheet. Meters N 0 15 30 60 90 Feet 0 50 100 200 300 Map projection: Web Mercator Comer coordinates: WGS84 Edge tics: UTM Zone 1ON WGS84 USDA Natural Resources Web Soil Survey Conservation Service National Cooperative Soil Survey Soil Map —Snohomish County Area, Washington (USDA Soil Map) 547100 547120 547140 547160 547180 547200 547220 547200 547M N 547240 47' 46 47" N bS 47' 46' 40" N 547240 m N 9/16/2022 Page 1 of 3 MAP LEGEND Area of Interest (AOI) Area of Interest (AOI) Soils 0 Soil Map Unit Polygons 0,0 Soil Map Unit Lines C Soil Map Unit Points Special Point Features V Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot O Landfill ALava Flow Marsh or swamp j* Mine or Quarry OMiscellaneous Water OPerennial Water V Rock Outcrop + Saline Spot Sandy Spot _ Severely Eroded Spot Q Sinkhole Slide or Slip 0o Sodic Spot Soil Map —Snohomish County Area, Washington (USDA Soil Map) MAP INFORMATION ® Spoil Area The soil surveys that comprise your AOI were mapped at 1:24,000. Q Stony Spot Very Stony Spot Warning: Soil Map may not be valid at this scale. Wet Spot Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil Other line placement. The maps do not show the small areas of Special Line Features contrasting soils that could have been shown at a more detailed scale. Water Features Streams and Canals Please rely on the bar scale on each map sheet for map measurements. Transportation .+. Rails Source of Map: Natural Resources Conservation Service Web Soil Survey URL: ..� Interstate Highways Coordinate System: Web Mercator (EPSG:3857) US Routes Maps from the Web Soil Survey are based on the Web Mercator Major Roads projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Local Roads Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. Background Aerial Photography This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Snohomish County Area, Washington Survey Area Data: Version 23, Aug 31, 2021 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Sep 2, 2018—Sep 25, 2018 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. uSDA Natural Resources Web Soil Survey 9/16/2022 Conservation Service National Cooperative Soil Survey Page 2 of 3 Soil Map —Snohomish County Area, Washington USDA Soil Map Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 3055 3057 Totals for Area of Interest Urban land-Alderwood complex, 0 to 5 percent slopes Urban land-Alderwood complex, 12 to 35 percent slopes 2.9 45.7% 3.5 54.3% 6.4 100.0% USDA Natural Resources Web Soil Survey 9/16/2022 Conservation Service National Cooperative Soil Survey Page 3 of 3 ArcGIS - City of Edmonds Watersheds Details I Basemap About Content Legend Legend Water h Streams Creek � Pipe Edmonds Schools Watersheds Deer Creek Edmonds Marsh Edmonds Way Fruitdale Trust Center . Legal . Contact Esri . ReportAbuse Share Print I Measure ArcGIS - City of Edmonds Watersheds Details I Basemap About Content Legend Legend Water h Streams Creek � Pipe Edmonds Schools Watersheds Deer Creek Edmonds Marsh Edmonds Way Fruitdale Trust Center . Legal . Contact Esri . ReportAbuse Share Print I Measure North Star Visions, LLC Sugar House Edmonds, WA APPENDIX B Offsite Flow Paths PACE NORTH STAR VISIONS, LLC SUGAR HOUSE DRAINAGE REPORT AUGUST 2023 THIS PAGE IS INTENTIONALLY LEFT BLANK. PACE City of Edmonds DOWNSTREAM EXHIBIT � sN22 v a 7 40 r xr* Legend 104% 2Z 24104'1 & B 8 , 4032 24o� 93 0 41 2 i 24111 11 3 241141 24107 o Z410 ' I 241 Storm Catch Basins o Edmonds 41141 24 1 J4118' 241 i20' 4115 21n 2 t 'e 2411 �- 1 t _ p Private ■ Infiltration 12 24� WIN 24127 2412 „ 41 t Storm Manholes 13 413` 2413 24201 24202 ■ 2!1�20) ,� O Edmonds O Private 4 1 241LI7 ■ 24211 1 3'. r 4 � � 1 Infiltration 4 o v 2 5 2421 , , �'i I'- • Detention Facilities 218, r 10 I� y? 2422 2JLI7 a1 _ o� ' '421� w PROJEC�3 - TO Culvert • <all other values> Yes 226 232 o 24 > 19 of r 24`- _-� 1 LOCATIC2 24 34 `� p o o O Facility Feature 43� ,a _ �1 = 5 �� _ - 10 Creeks Storm Line 2 _ �0 - � _ — <all other values> r a v � 24" PIPE UPSTREAM AREA 102C1 O � No, BNSF; No, COUNTY; No, LYNI TERRACE; No, POF SHORELINE; No, STATE; No, WOE — SHOREMOUNTLINE; Yes, EDMONDS; Yes, PRIVATE; 1 O 1071 PD15-27 10204 d Facility Lines y ► O y� p D D 0 — Storm Ditch Contour Lines PR XIM 1 10 f� MILE O M — 50; 100 ` PROJ CT Sections Boundary Sactinnc Notes NOTE: DOWNSTREAM STORM DRAIN PIPES ARE NOTED 12" UNLESS OTHERWISE 1: 3,031 O 0 252.60 505.2 Feet 4,514 376.2 This ma is a user generated static output from an Internet mapping B p pp B site and is for p f WGS_1984_Web-Mercator _Auxiliary -Sphere reference only. Data layers that appear on this map may or may not be accurate, current, or otherwise reliable. © City of Edmonds THIS MAP IS NOT TO BE USED FOR DESIGN OR CONSTRUCTION North Star Visions, LLC Sugar House Edmonds, WA APPENDIX C Site Maps PACE NORTH STAR VISIONS, LLC SUGAR HOUSE DRAINAGE REPORT AUGUST 2023 THIS PAGE IS INTENTIONALLY LEFT BLANK. PACE 0 20 1 "=20' Scale Feet a_ o o �m p Q. 70 Op Jij O� v'� — "z -386- >p y7G02 o 'o cp. � SHED o6, 6' WOOD F CE X °' — —��92 FENCE �1 27' E 08 'S' — — — 5' CHAINLIN C3 0\� ��06,0d, 4' CHANLINK moo \ UR BO HEDG 0 \ N 27'5 51 E 1 2.24 4 WOOD---388 WOOD I I cS b S 110, rn 2 C) O �i 0 30' O — n 9 2 co 00 p01" i \ I f O� �!y O <i �i9 O \ ,�� ' o o U' oz oo �.p p� cu 0 G2 �2 s 0c9oo��" � yy � _0 y p tip ��- �O��F -VIP � o O C> -o \ rn Oyu cw o \ �o IQ �s � IIQ ' WOOD FENCE /SNP OyA v o I W D a■ :\Projects\362 (KLN Construction)\025-22 (sugar House)\Dwg\figures\TIR Figures\Euisting.dwg 36x24 \ i DETENTION o I PIPE 0 20 � 1 "=20' o Scale F \ 386- 'o L SHED ,ern 0 _ 2 X 9� ... .. - ----- �� \ --97. ........ Ile 30' ---388 -- -- —--.—��= o I/01 TOP OF STEEP SLOPE PROPOSED��\I I I o HOUSE CONNECTS -- a , INTO — ^' DETE TION \ I m X N I � II PI I I o Z o �T \ (n \ — �I o � A 0/1�0 cn W �� IMPERVIOUS AREA: EXISTING IMPERVIOUS AREA: 0 SF PROP. HOUSE a (W/ROOF OVERHANG): 2,526 SF (DETENTION PIPE) o PROPOSED WALKWAY/PATIO: 50 SF (DETENTION PIPE) PROPOSED ASPHALT DRIVEWAY: 1,817 SIF (DETENTION PIPET o TOTAL IMPERVIOUS AREA: a n 0 J f 1 J 7 I V J V ri 4,393 SF :\Projects\362 (KLN Construction)\025-22 (sugar House)\Dwg\figures\TIR Figures\Developed.dwg 36x24 2 i N D u ENGINEER: 3501 COLBY AVE, SUITE 101 EVERETT, WA. 98201 (425) 486-6533 AndyReOpoceengrs.com CONTACT: ANDY REAVES, PE NORTH STAR VISIONS, LLC 19020 33RD AVE W, SUITE LYNNWOOD, WA 98036 NOTES: 1. ROOF RUN OFF WILL BE CONNECTED TO DOWNSPOUTS TO CLEANOUTS AND FOOTING DRAIN, TO TIGHTLINED TO PROPOSED R-TANK. 2. FINE GRADING AROUND THE PROPOSED STRUCTURES WILL BE PERFORMED TO ENSURE SLOPES ARE AWAY FROM THE PROP. DWELLING. 3. CATCH BASIN INLET PROTECTION SHALL BE ADDED TO ANY CATCHBASIN DIRECTLY DOWNSTREAM AND ADJACENT TO THIS SITE. 4. TEMPORARY STOCKPILE AREA SHALL BE COVERED WITHIN 24 HOURS. 5. ALL DISTURBED SOILS WILL BE COMPOST AMENDED PER BMP T5.13. 6. INSTALL AND MAINTAIN ALL TESC MEASURES ACCORDING TO APPROVED PLANS, CITY OF EDMONDS STANDARD DETAILS, AND ALL OTHER MEASURES THAT MAY BE REQUIRED DURING CONSTRUCTION. 7. PROPOSED STRUCTURE WILL BE REQUIRED TO PROVIDE NFPA 13D RESIDENTIAL FIRE SPRINKLER SYSTEM REGARDLESS OF BUILDING SQUARE FOOTAGE. 8. INSTALL 14 GA. VINYL COATED TRACER WIRE (TAPED TO PLASTIC PIPE EVERY 10') TO BE GROUNDED AT METER AND PROPOSED HOME. 9. MINIMUM HORIZONTAL SEPARATION BETWEEN WATER AND SEWER IS 10'. 10. MINIMUM HORIZONTAL SEPARATION BETWEEN WATER AND STORM LINES IS 5'. 11. ALL FINAL RESTORATION SHALL BE COMPLETED BY THE CONTRACTOR NOT THE CITY OF EDMONDS. 12. MIN. 3' SEPERATION IS REQUIRED BETWEEN DRY UTILITIES (POWER, GAS, PHONE, CABLE, ECT) AND WET UTILITIES (STORM, SEWER, WATER). ALL UTILITIES INSTALLED PER ECDG 18.05. 13. MIN. 2' COVER IS REQUIRED FOR ALL PIPES LOCATED UNDER DRIVABLE SURFACE AND 1' MIN. COVER UNDER LANDSCAPE AREAS. 14. THE 6" SSCO AT THE PROPERTY LINE SHALL HAVE A 12" CAST IRON LAMPHOLE COVER WITH 11h" HEXBOLTS. 5' CH INLIN 0 15' 2.5' 10' DRIVE AISLE 1-2% f1-2% - — 1.13, I r 1-1/2" WATER 2" HMA CLASS 1 /2" PG 58H-22 6" 5/8" MINUS CSTC 36" SD PIPE 6" DRY JOINT UTILIT 3.77' MINIMUM 1 SCHEDULE 40 WATER ND PL SW), PER PIL .. • 0 . .. 6' WOOD CE a �d • �O�ell-I Y WOOD I \ o \\ 6') 6WOOD FENCE 2.5' 2775C' M-Ef-1/02.24- '/4' i I 01, z � o\ CD \ CB RIM= 387.9 I E= 385.05 10 LF-6" SD @ 0.6i JOINT DRY � UTILITY TRENCH X. S WE SERVICE I i (POWER, COMM. E=3- 0.8 I z 384.8 CABLE ) X. 31-6" SO o 2 123 LF-4" PVC MIN o co 4% (2% MIN SLOPE), EX.�SS�-j(E o 2' MIN. PIPE COVER ON SEWER SERVICE (TYP) - v � sy 0 <0 oOo" 00 0 SDCB #2 0 RIM385 =390.0 (N/SE) N � � N oCn I Z of \ o CCC 0 � G 0jy cn EX. FIRE n HYDRANT /o�P �tiA W D NOTE: UTILITY SEPARATION BETWEEN PROPOSED 3' UTILITIES DOES NOT MEET THE MINIMUM CLEARANCES FOR CITY OF EDMONDS STANDARDS. �4" SS AIR ♦_ 0 20 1 "=20' Scale Feet n R:\Projects\362 (KLN Construction\025-22 (Sugar House\Dwg\sheets\SH_CrossSection Exhibit.dwg 36x24 A UTILITY DRIVEWAY SECTION - SCALE: 1"=5' Tara Beitler From: Shuster, Jerry <jerry.shuster@edmondswa.gov> Sent: Friday, June 9, 2023 1:01 PM To: Tara Beitler Subject: RE: Utility Clearances vs Detention Pipe Ta ra, Your question was about utility clearances. I believe the clearances shown in the drawing will likely be approved. --Jerry From: Tara Beitler <Tarab@paceengrs.com> Sent: Friday, June 9, 2023 12:52 PM To: Shuster, Jerry <jerry.shuster@edmondswa.gov> Subject: RE: Utility Clearances vs Detention Pipe Sorry, I am not clear. Do you want the 36" diameter detention pipe? Thanks, Ta ra Tara Beitler, PE Project Engineer 3501 Colby Avenue I Suite 101 r,..AC � Everett WA 98201 p. 425.486.6533 An Ergineermg �Brvicerg Ccoipany Voted Zweig Best Places to Work and PSBJ Top 100 Fastest Growing Firms in the Northwest From: Shuster, Jerry <ierry.shuster@edmondswa.gov> Sent: Friday, June 9, 2023 12:31 PM To: Tara Beitler <Tarab@paceengrs.com> Subject: RE: Utility Clearances vs Detention Pipe Ta ra, We don't see any alternative and will likely be approved. Please be sure and add the driveway slope to one of the plan sheets. Note: this is not an official approval of this plan sheet. Sincerely, --Jerry From: Tara Beitler <Tarab@paceengrs.com> Sent: Friday, June 9, 2023 11:55 AM To: Shuster, Jerry <ierry.shuster@edmondswa.gov> Cc: Lucas Kragt <lucas@village-life.net>; Krista Stewart <KristaS@paceengrs.com>; Andy Reaves <AndvRe@paceengrs.com> Subject: Utility Clearances vs Detention Pipe Good Morning Jerry, Please the attached plan that shows what the utilities clearances would be if a 36" diameter detention pipe was placed in the driveway. Please let us know how you would like us to proceed. Thanks, Ta ra Tara Beitler, PE Project Engineer 3501 Colby Avenue I Suite 101 PAC � Everett WA 98201 p. 425.486.6533 An Cngineermg SCrviCBB Coiipari) Voted Zweig Best Places to Work and PSBJ Top 100 Fastest Growing Firms in the Northwest COPY OF EXHIBIT SENT TO CITY OF EDMONDS 06/28/2023 FNC,INFFR- 3501 COLBY AVE, SUITE 101 EVERETT, WA. 98201 (425) 486-6533 AndyRe@poceengrs.com CONTACT: ANDY REAVES, PE OWNER- L NORTH STAR VISIONS, LLC �� 3pc2 FENCE/ N 27 �f" E ' 19020 33RD AVE W, SUITE 45 -— ' 5 LYNNWOOD, WA 98036 gtt ' CH. _ 4 00OO / \_ i1— MINIMUM_1 SCHEDULE 40 WATER SER CE ND EX. 1" WATER METERS (ON 4 ND PL SW), PER PL 20050005610678. 6OOD F CE X .� LMI ,6 ...m. .....=F-- --- WOOD t�` \\1 stogy I \ I \ L O \ 40 I \ d NOTES : \ 1. ROOF RUN OFF WILL BE CONNECTED TO DOWNSPOUTS TO CLEANOUTS AND FOOTING DRAIN, TO TIGHTLINED TO PROPOSED R-TANK. ® .: & Y I^ V,\ 2. FINE GRADING AROUND THE PROPOSED STRUCTURES WILL BE PERFORMED TO ENSURE SLOPES ARE AWAY FROM THE PROP. DWELLING. 3. CATCH BASIN INLET PROTECTION SHALL BE ADDED TO ANY CATCHBASIN DIRECTLY DOWNSTREAM AND ADJACENT TO THIS SITE. _ -404, 4. TEMPORARY STOCKPILE AREA SHALL BE COVERED WITHIN 24 HOURS. \ 5. ALL DISTURBED SOILS WILL BE COMPOST AMENDED PER BMP T5.13. 6. INSTALL AND MAINTAIN ALL TESC MEASURES ACCORDING TO APPROVED PLANS, CITY OF EDMONDS STANDARD DETAILS, AND ALL OTHER MEASURES THAT MAY BE REQUIRED DURING CONSTRUCTION. 7. PROPOSED STRUCTURE WILL BE REQUIRED TO PROVIDE NFPA 13D RESIDENTIAL FIRE SPRINKLER SYSTEM REGARDLESS OF BUILDING SQUARE FOOTAGE. 8. INSTALL 14 GA. VINYL COATED TRACER WIRE (TAPED TO PLASTIC PIPE EVERY 10') TO BE GROUNDED M NIMUMT HORIZO TADL SEPARATIONH .BETWEEN NEEDS 5' MINIMUM WATER AND SEWER IS 10'. SEPERATION FROM 10. MINIMUM HORIZONTAL SEPARATION BETWEEN WATER AND STORM LINES IS 5'. WATER 11. ALL FINAL RESTORATION SHALL BE COMPLETED BY THE CONTRACTOR NOT THE CITY OF EDMONDS. 1.44' 12. MIN. 3' SEPERATION IS REQUIRED BETWEEN DRY UTILITIES (POWER, GAS, PHONE, CABLE, ECT) AND WET UTILITIES (STORM SEWER WATER) ALL UTILITIES --�1= \ 01 ON \\ C / LI N 51 ' 4 6' WOOD FENCE 15' 2.5' , 10' DRIVE AISLE 1 -2/. �1-2/. INOTE: UTILITY SEPARATION BETWEEN PROPOSED 22' 1.35' 3.17' 1.3' UTILITIES DOES NOT MEET THE MINIMUM CLEARANCES INSTALLED PER ECDG 181 1-1/2" WATER FOR CITY OF EDMONDS 13. MIN. 2' COVER IS REQUIRED FOR ALL PIPES Water is burried STANDARDS. LOCATED UNDER DRIVABLE SURFACE AND 1' MIN. COVER UNDER LANDSCAPE AREAS. approx. 3' 14. THE 6" SSCO AT THE PROPERTY LINE SHALL 36" DETENTION PIPE %� HAVE A 12" CAST IRON LAMPHOLE COVER WITH 11h" L ACR HEXBOLTS. 12" DRY JOINT UTILITY 4 SS Design KIDS Drawn 3/01 /23 A UTILITY DRIVEWAY SECTION Date An Engineenng Services Company SCALE: 1"=5' 362-025-22 Project No. 2.5' I I o cb 6� z � CD 36', I E approx. 385.3' N 27°5C�'51 �E 1'02.2�4' WO D) r90 388 �s ssco 2 JOINT DRY RIM= 390.87 UTILITY TRENCH X. S WE SERVICE IE= 385.09 (POWER, COMM. E=3.0.8 z W/LOCKING 12" CI �y CABLE) = 384.8 n LAMPHOLE COVERS �i 3 -6" S0 0 1�" HEXBOLTS (TYP) 2 123 LF-4" PVC MIN @ co <2 4% (2% MIN SLOPE), EX.E o 2' MIN. PIPE COVER ON SEWER �I SERVICE (TYP) - o � 0 2 �y c0oo p --A N 0)j 7 I, �< O o I N �ooA "' 0 0 03 r ° \ o W � � G `90 `90 EX. FIRE HYDRANT D �tiA L W D Dimensions have been revised so that the sewer can be constructed within the 15' driveway 0 20 1 "=20' Scale Feet R:\Projects\362 (KLN Construction\025-22 (Sugar House\Dwg\sheets\SH_CrossSection Exhibit.dwg 36x24 North Star Visions, LLC Sugar House Edmonds, WA APPENDIX D Calculations PACE NORTH STAR VISIONS, LLC SUGAR HOUSE DRAINAGE REPORT AUGUST 2023 THIS PAGE IS INTENTIONALLY LEFT BLANK. PACE MGS FLOOD PROJECT REPORT Program Version: MGSFlood 4.58 Program License Number: 201610006 Project Simulation Performed on: 08/14/2023 9:29 AM Report Generation Date: 08/14/2023 9:29 AM Input File Name Project Name: Analysis Title: Comments: 362-025-22 Vault.fld Sugar House Computational Time Step (Minutes): PRECIPITATION INPUT 15 Extended Precipitation Time Series Selected Full Period of Record Available used for Routing Climatic Region Number: 14 Precipitation Station : 96003605 Puget East 36 in_5min 10/01/1939-10/01/2097 Evaporation Station 961036 Puget East 36 in MAP Evaporation Scale Factor : 0.750 HSPF Parameter Region Number: 3 HSPF Parameter Region Name : USGS Default ********** Default HSPF Parameters Used (Not Modified by User) *************** ********************** WATERSHED DEFINITION *********************** Predevelopment/Post Development Tributary Area Summary Predeveloped Post Developed Total Subbasin Area (acres) 0.100 0.100 Area of Links that Include Precip/Evap (acres) 0.000 0.000 Total (acres) 0.100 0.100 ----------------------SCENARIO: PREDEVELOPED Number of Subbasins: 1 Subbasin Till Forest PreDev---------- ------- Area (Acres) 0.100 Subbasin Total 0.100 ----------------------SCENARIO: POSTDEVELOPED Number of Subbasins: 1 ---------- Subbasin : Dev---------- ------- Area (Acres) Impervious 0.100 Subbasin Total 0.100 ************************* LINK DATA ******************************* ----------------------SCENARIO: PREDEVELOPED Number of Links: 0 ************************* LINK DATA ******************************* ----------------------SCENARIO: POSTDEVELOPED Number of Links: 1 Link Name: Vault Link Type: Structure Downstream Link: None User Specified Elevation Volume Table Used Elevation (ft) Pond Volume (cu-ft) 100.00 0. 100.20 8. 100.40 20. 100.60 37. 100.80 56. 101.00 74. 101.20 96. 101.40 119. 101.60 138. 101.80 161. 102.00 183. 102.20 201. 102.40 220. 102.60 237. 102.80 249. 103.00 257. 103.20 257. 103.40 257. 103.60 257. 103.80 258. 104.00 258. 104.20 258. 104.40 258. 104.60 258. 104.80 258. 105.00 258. 105.20 259. 105.40 259. 105.60 259. 105.80 259. 106.00 259. Hydraulic Conductivity (in/hr) : 0.00 Massmann Regression Used to Estimate Hydralic Gradient Depth to Water Table (ft) : 100.00 Bio-Fouling Potential : Low Maintenance : Average or Better Riser Geometry Riser Structure Type : Circular Riser Diameter (in) : 6.00 Common Length (ft) : 0.000 Riser Crest Elevation : 102.50 ft Hydraulic Structure Geometry Number of Devices ---Device Number 1 --- Device Type Circular Orifice Control Elevation (ft) 100.00 Diameter (in) 0.50 Orientation : Horizontal Elbow : Yes **********************FLOOD FREQUENCY AND DURATION STATISTICS******************* ----------------------SCENARIO: PREDEVELOPED Number of Subbasins: 1 Number of Links: 0 ----------------------SCENARIO: POSTDEVELOPED Number of Subbasins: 1 Number of Links: 1 ********** Subbasin: Dev ********** Flood Frequency Data(cfs) (Recurrence Interval Computed Using Gringorten Plotting Position) Tr (yrs) Flood Peak (cfs) -------------------------------------- -------------------------------------- 2-Year 3.540E-02 5-Year 4.713E-02 10-Year 5.567E-02 25-Year 6.676E-02 50-Year 8.567E-02 100-Year 0.102 200-Year 0.110 500-Year 0.120 ********** Link: Vault ********** Link Inflow Frequency Stats Flood Frequency Data(cfs) (Recurrence Interval Computed Using Gringorten Plotting Position) Tr (yrs) Flood Peak (cfs) -------------------------------------- -------------------------------------- 2-Year 3.540E-02 5-Year 4.713E-02 10-Year 5.567E-02 25-Year 6.676E-02 50-Year 8.567E-02 100-Year 0.1024 200-Year 0.110 500-Year 0.120 100-YR FLOW INTO THE VAULT ********** Link: Vault WSEL Frequency Data(ft) (Recurrence Interval Computed Using Gringorten Plotting Position) Tr (yrs) WSEL Peak (ft) -------------------------------------- -------------------------------------- 1.05-Year 101.249 1.11-Year 101.439 1.25-Year 101.600 2.00-Year 102.072 3.33-Year 102.509 5-Year 102.520 10-Year 102.527 25-Year 102.534 50-Year 102.536 100-Year 102.540 ********** Link WSEL Stats ***********Groundwater Recharge Summary ************* Recharge is computed as input to Perind Groundwater Plus Infiltration in Structures Total Predeveloped Recharge During Simulation Model Element Recharge Amount (ac-ft) Subbasin: PreDev 15.283 Total: 15.283 Total Post Developed Recharge During Simulation Model Element Recharge Amount (ac-ft) Subbasin: Dev Link: Vault Total: Total Predevelopment Recharge is Greater than Post Developed Average Recharge Per Year, (Number of Years= 158) Predeveloped: 0.097 ac-ft/year, Post Developed: 0.000 ac-ft/year ***********Water Quality Facility Data ************* ----------------------SCENARIO: PREDEVELOPED Number of Links: 0 ----------------------SCENARIO: POSTDEVELOPED Number of Links: 1 ********** Link: Vault Basic Wet Pond Volume (91 % Exceedance): 411. cu-ft Computed Large Wet Pond Volume, 1.5*Basic Volume: 616. cu-ft 2-Year Discharge Rate : 0.009 cfs 15-Minute Timestep, Water Quality Treatment Design Discharge On-line Design Discharge Rate (91 % Exceedance): 0.01 cfs Off-line Design Discharge Rate (91 % Exceedance): 0.01 cfs Infiltration/Filtration Statistics -------------------- Inflow Volume (ac-ft): 39.43 Inflow Volume Including PPT-Evap (ac-ft): 39.43 Total Runoff Infiltrated (ac-ft): 0.00, 0.00% Total Runoff Filtered (ac-ft): 0.00, 0.00% Primary Outflow To Downstream System (ac-ft): 39.43 Secondary Outflow To Downstream System (ac-ft): 0.00 Volume Lost to ET (ac-ft): 0.00 Percent Treated (Infiltrated+Filtered+ET)/Total Volume: 0.00% ***********Compliance Point Results ************* Scenario Predeveloped Compliance Subbasin: PreDev Scenario Postdeveloped Compliance Link: Vault *** Point of Compliance Flow Frequency Data *** Recurrence Interval Computed Using Gringorten Plotting Position Predevelopment Runoff Tr (Years) Discharge (cfs) Postdevelopment Runoff Tr (Years) Discharge (cfs) ********** 2-Year 1.638E-03 2-Year 9.121 E-03 5-Year 2.793E-03 5-Year 2.593E-02 CHECK: 10-Year 3.830E-03 10-Year 3.387E-02 PROPOSED 10-YR < PREDEV 10-YR 0.0339 < 0.0383 TRUE 25-Year 5.123E-03 25-Year 4.396E-02 50-Year 6.867E-03 50-Year 4.716E-02 100-Year 7.512E-03 100-Year 5.307E-02 200-Year 1.129E-02 200-Year 6.238E-02 500-Year 1.638E-02 500-Year 7.472E-02 ** Record too Short to Compute Peak Discharge for These Recurrence Intervals 100 10 u Figure V-12.8: Riser Inflow Curves 1l1MNllll11M = SIN%� A Anw, a P i All 30 27 P-PA MAjWMAP PP 0.10 IMEN 0.1 DEPARTMENT OF ECOLOGY State of Washington ,o HEAD IN FEET (measured from crest of riser) Q =9.739 DH"Z 00riNcc-3.782 Dt H1!2 0 in cfs, D and H in feet Slope change occurs at weir -orifice transition Riser Inflow Curves Revised June 2016 Please see http://www.ecy.wa.gov/copyright.html for copyright notice including permissions, limitation of liability, and disclaimer. 2019 Stormwater Management Manual for Western Washington Volume V - Chapter 12 - Page 964 North Star Visions, LLC Sugar House Edmonds, WA APPENDIX E Geotechnical Report PACE NORTH STAR VISIONS, LLC SUGAR HOUSE DRAINAGE REPORT AUGUST 2023 THIS PAGE IS INTENTIONALLY LEFT BLANK. PACE August 22, 2022 Updated September 23, 2022 ES-8626.01 North Star Visions, LLC 19020 — 33rd Avenue West, Suite 450 Lynnwood, Washington 98036 Attention: Mr. Lucas Kragt, P.E. Subject: Geotechnical Evaluation Proposed Single -Family Residence Sugar and Scovill Property 10234 — 242nd Place Southwest Edmonds, Washington Earth Solutions N W «C Earth Solutions NW LLC Geotechnical Engineering, Construction Observation/Testing and Environmental Services Reference: ASPI, LLC, Existing Conditions Map, dated June 20, 2022 PACE Engineers, Building Site Plan, dated September 8, 2022 Malsam Tsang Structural Engineering Structural Calculations for: Plan 3132-02A, dated July 5, 2022 Tubbs Geosciences Geotechnical Engineering Report, File No. HAL2-01, dated January 9, 2004 Field Report, dated April 1, 2004 James P. Minard Geologic Map of the Edmonds East and Part of the Edmonds West Quadrangles Washington, 1983 United States Department of Agriculture (USDA) Web Soil Survey (WSS) Department of Ecology Stormwater Management Manual for Western Washington Amended December 2014 Edmonds City Code Chapter 23.80 (Geologically Hazard Areas) Dear Mr. Kragt: As requested, Earth Solutions NW, LLC (ESNW) has prepared this geotechnical evaluation for the proposed single-family residence; this report has been updated based on site specific topographic data and proposed site plan. As part of our scope of services, we completed a subsurface exploration, laboratory and engineering analyses, and prepared this written report with our findings and recommendations for the proposed project. Based on our evaluation, the proposed project is feasible from a geotechnical standpoint. 15365 N.E. 90th Street, Suite 100 • Redmond, WA 98052 • (425) 449-4704 • FAX (425) 449-4711 North Star Visions, LLC August 22, 2022 Updated September 23, 2022 Protect Description ES-8626.01 Page 2 The subject site is located at 10234 — 242nd Place Southwest in Edmonds, Washington, as illustrated on the attached Vicinity Map (Plate 1). The site consists of one tax parcel (Snohomish County parcel number 0055500000-4902) totaling approximately 0.22 acres of land. The property is currently undeveloped and vegetated primarily by grass and mature trees around the site perimeter; some invasive vegetation is present along the sloped area in the southwest corner of the site. Site topography gently to moderately descends towards the north and west; the southwestern corner of the property moderately to steeply descends to the neighboring property. The subject site is bordered to the east, south, and west by single-family residences and to the north by a single-family residence and 242nd Place Southwest. Based on the referenced site plan, the subject site will be developed with a single-family residence and associated improvements. Grading activities will include cuts of up to about four feet to establish the planned building alignments. A rain garden will be constructed near the southwest corner of the property to control stormwater runoff. Site improvements will also include underground utility installations. The proposed residential structure will consist of relatively lightly loaded wood framing supported on conventional foundations. Based on the referenced structural calculations, wall loads will be on the order of 1 to 2 kips per linear foot, isolated footing loads will be less than 20 kips, and we anticipate slab -on -grade loading of 150 pounds per square foot (psf). If the above design assumptions are incorrect or change, ESNW should be contacted to review the recommendations in this report. ESNW should review the final design to verify the geotechnical recommendations provided in this report have been incorporated into the plans. Subsurface Conditions As part of this geotechnical evaluation, an ESNW representative observed, logged, and sampled three hand auger borings on May 11, 2022, advanced at accessible locations within the proposed development area, using hand tools and a half -inch diameter steel T-probe to probe the subgrade of the test holes. The approximate locations of the hand auger borings are depicted on the Hand Auger Boring Location Plan (Plate 2). Please refer to the hand auger boring logs provided as an attachment to this report for a more detailed description of subsurface conditions. Representative soil samples collected at the test pit locations were analyzed in general accordance with the Unified Soil Classification System (USCS) and USDA methods and procedures. ESNW also reviewed the referenced Tubbs Geosciences geotechnical engineering report that was prepared for the properties to the west (downslope) of the subject site. Earth Solutions NW. LLC North Star Visions, LLC August 22, 2022 Updated September 23, 2022 Topsoil ES-8626.01 Page 3 Topsoil was observed extending to depths of approximately four to six inches below the existing ground surface (bgs. The topsoil was characterized by dark brown color and fine organic material. Native Soil Underlying the topsoil, native soil at the test pit locations was observed to consist of silty gravel with sand, poorly graded sand with silt and gravel, and poorly graded gravel with sand (USCS: GM, SP-SM, and GP, respectively). Overall soil relative density generally increased with depth, extending to the maximum exploration depth of about three feet bgs. The native soil was generally observed in a weakly cemented condition beginning at about one foot bgs at HA-2. Geologic Setting The referenced geologic map resource identifies Vashon till (Qvt) across the site and Advanced outwash (Qva) mapped immediately to the west of the subject site. As reported on the geologic map resource, Vashon till typically consists of a nonsorted mixture of clay, silt, sand, pebbles, cobbles, and boulders. The till was deposited directly by ice advanced over previously deposited sediment and rocks. The advance outwash in characterized as mostly clean and well -stratified sand with some pebbles. Additionally, the referenced WSS resource identifies urban land- Alderwood complex as the primary soil unit underlying the subject site. The Alderwood series was formed in glacial till plains. Based on our field observations, native soils on the subject site are generally consistent with the geologic setting outlined in this section. Groundwater Groundwater seepage was not observed at the hand auger boring locations during the fieldwork (May 2022). However, zones of groundwater seepage should be expected in deeper excavations at this site. Groundwater seepage rates and elevations fluctuate depending on many factors, including precipitation duration and intensity, the time of year, and soil conditions. Geologically Hazardous Areas Assessment As part of this geotechnical evaluation, the referenced chapter of the ECC was reviewed. Based on our investigation and review, the following topics related to development plans and site conditions are addressed: Earth Solutions NW. LLC North Star Visions, LLC ES-8626.01 August 22, 2022 Page 4 Updated September 23, 2022 Erosion Hazard Areas — ECC 23.80.020.A. With respect to erosion hazard areas, section 23.80.020 of the ECC defines erosion hazards as "at least those areas identified by the U.S. Department of Agriculture's Natural Resources Conservation Service as having a `moderate to severe', `severe', or `very severe' rill and inter -rill erosion hazard. Erosion hazard areas are also those areas impacted by shoreland and/or stream bank erosion. Within the city of Edmonds, erosion hazard areas include: 1. Those areas of the city of Edmonds containing soils that may experience severe to very severe erosion hazard. This group of soils includes, but is not limited to, the following when they occur on slopes of 15 percent or greater: a. Alderwood soils (15 to 25 percent slopes); b. Alderwood/Everett series (25 to 70 percent slopes), and; c. Everett series (15 to 25 percent slopes). 2. Coastal and stream erosion areas which are subject to the impacts from lateral erosion related to moving water such as stream channel migration and shoreline retreat; 3. Any area with slopes of 15 percent or greater and impermeable soils interbedded with granular soils and springs or ground water seepage, and; 4. Areas with significant visible evidence of ground water seepage, and which also include existing landslide deposits regardless of slope." The native soil is generally consistent with Alderwood or Everett series soils. Based on the ECC definition, the areas sloped greater than 15 percent within and adjacent to the property classify as erosion hazard areas. In our opinion, the proposed construction will not increase the erosion hazard for the site or adjacent properties, provided typical Best Management Practices (BMPs), such as silt fences, covering exposed soil, and permanent landscaping, are implemented during and after construction as warranted. Earth Solutions NW. LLC North Star Visions, LLC ES-8626.01 August 22, 2022 Page 5 Updated September 23, 2022 Landslide Hazard Areas — ECC 23.80.020.B. With respect to landslide hazard areas, section 23.80.020 of the ECC defines landslide hazard areas as areas potentially subject to landslides based on a combination of geologic, topographic, and hydrologic factors. They include areas susceptible because of any combination of soil, slope gradient, slope aspect, structure, hydrology, or other factors. Within the city of Edmonds, landslide hazard areas specifically include: 1. Areas of ancient or historic failures in Edmonds which include all areas within the earth subsidence and landslide hazard area as identified in the 1979 report of Robert Lowe Associates and amended by the 1985 report of GeoEngineers, Inc., and further discussed in the 2007 report by Landau Associates; 2. Coastal areas mapped as class U (unstable), UOS (unstable old slides) and URS (unstable recent slides) in the Department of Ecology Washington coastal atlas; 3. Areas designated as quaternary slumps, earthflows, mudflows, or landslides on maps published by the United States Geological Survey or Washington State Department of Natural Resources; 4. Any slope of 40 percent or steeper that exceeds a vertical height of 10 feet over a 25-foot horizontal run. Except for rockeries that have been engineered and approved by the engineer as having been built according to the engineered design, all other modified slopes (including slopes where there are breaks in slopes) meeting overall average steepness and height criteria should be considered potential landslide hazard areas; 5. Any slope with all three of the following characteristics: a. Slopes steeper than 15 percent; b. Hillsides intersecting geologic contacts with relatively permeable sediment overlying a relatively impermeable sediment, and; c. Springs or ground water seepage. 6. Any area potentially unstable as a result of rapid stream incision or stream bank erosion; 7. Any area located on an alluvial fan, presently subject to, or potentially subject to, inundation by debris flow or deposition of stream -transported sediments, and; 8. Any slopes that have been modified by past development activity that still meet the slope criteria. Earth Solutions NW. LLC North Star Visions, LLC August 22, 2022 Updated September 23, 2022 ES-8626.01 Page 6 It is our opinion the site exhibits good slope stability characteristics as indicated by no observed evidence suggesting previous shallow, debris -flow -type failures or deep-seated rotational failures and/or movements. Additionally, ESNW did not observe any evidence of active springs or groundwater seepage during our site visit. Based on site observations and review of available topographic data, the slope located in the southwest corner of the subject site moderately to steeply descends about 16 to 18. Based on site specific topographic data, a portion of the on -site slope area is up to approximately 50 percent across and elevation change of less than 10 feet; based on interpolation of the off -site slope area, it is likely that a portion of the slope is 40 percent or steeper across an elevation change of at least 10 feet. In this respect, it is likely that at least a portion of the slope area would be considered a landslide hazard area per above criterion 4. Mapping of Geologically Hazardous Areas — ECC 23.80.030 Review of available geologically hazardous areas indicates the slope area in the southwest corner of the site is an erosion hazard area and a portion of the slope is a landslide hazard area; we understand these designations are based on lidar topographic data only. Special Study and Report Requirements — ECC 23.80.050 A. This geotechnical report and geological hazards assessment was completed by a professional engineer licensed in the state of Washington with experience analyzing geologic hazards throughout the Puget Sound region. B. The following areas have been reviewed and addressed: 1. The project area includes the subject site as delineated in the referenced site plan. 2. Other similarly localized areas of 15 to 40 percent slopes are mapped within 200 feet of the subject site. C. This geological hazards assessment included a field investigation and an assessment of geologic hazards. This geotechnical report has been prepared, stamped, and signed by a qualified professional. 1. It is our opinion the level of analysis completed for this geological hazards assessment is appropriate for the scale and scope of the project and scale of the geological hazard areas present. 2. A discussion of all geologically hazardous areas on the site and any geologically hazardous areas off site potentially impacted by the proposed project is provided in this report. Earth Solutions NW. LLC North Star Visions, LLC August 22, 2022 Updated September 23, 2022 ES-8626.01 Page 7 3. Based on the results of our study and on -site observations, the proposed project will not decrease slope stability or pose an unreasonable threat to persons or property either on or off site. These conclusions are based on the current conditions of the slope in question and proposed site design; grades will be lowered in the project area and the building will be appropriately setback from the top of the steep slope area. 4. This geological hazard assessment is provided as adequate information to comply with requirements of ECC geological hazards. 5. This geotechnical report generally follows the guidelines set forth in the Washington State Department of Licensing Guidelines for Preparing Engineering Geology Reports in Washington (2006). 6. It is our opinion a landslide hazard minimum building setback of 10 feet (as measured from face of slope, see Plate 3), and erosion hazard mitigation recommendations are provided in this report. D. We are not aware of a previous study completed for the subject site. We reviewed the referenced geotechnical report that was prepared for the adjacent properties to the west. E. The mitigation recommendations include a minimum 10-foot building setback, erosion control measures, directing stormwater away from the slope area, and installing an impermeable liner for the proposed rain garden. F. This geological hazards assessment and geotechnical report should be reviewed as part of the overall submittal package. 1. Please refer to the referenced site plan prepared by PACE Engineers. a. The height of the slopes and slope gradients are discussed in this report have been determined using both site specific topographic data and publicly available topography data. b. Springs, seeps, or other surface expressions of groundwater were not observed on or immediately adjacent to the site. c. Surface water runoff features were not observed within the subject site. 2. Requested hazard analysis items: a. Vegetative cover across the landslide hazard area generally consists of mature trees with invasive ivy and blackberry groundcover. b. Subsurface conditions are described in the Subsurface Conditions section of this report. Earth Solutions NW. LLC North Star Visions, LLC August 22, 2022 Updated September 23, 2022 ES-8626.01 Page 8 c. Surface and groundwater conditions are discussed in previous sections of this report. Based on site surface and subsurface conditions, there may have been some minor grade cuts in some areas of the site. Based on surface conditions and review of the referenced Tubbs Geosciences field report, the portion of the slope that extends on the neighboring property was previously cut to existing slope gradients and a tiered block wall was constructed at the toe. d. The slopes within and adjacent to the subject site generally exhibit good overall stability. We anticipate very low impact on the stability of the slope from the proposed project. e. The slopes within and adjacent to the subject site are not characterized as bluffs and we do not anticipate a retreat of the slopes to occur. f. Based on the slope conditions and historic modifications to the toe of the slope on the adjacent property, it is our opinion that the run -out hazard of the slope would likely be associated with surficial debris flow and toppling of the block walls within the adjacent property. This would likely be a result of saturation of surficial looser soil along the slope. g. The proposed project will include lowering grades to the northeast of the slope area. The stability of the slope area is considered good. h. We recommend the building be setback at least 10 feet from the face of the steep slope area (see Plate 3). The proposed surface and subsurface drainage system is designed to collect stormwater and groundwater within the proposed project area and direct it to a controlled stormwater system. We recommend installing an impermeable liner for the proposed rain garden. It is our opinion that the vulnerability of the site to erosion will not be increased by the proposed surface and subsurface drainage system. k. In our opinion, if the proposed addition and deck are supported on a deep foundation system as recommended in this report, the location of the improvements are suitable relative to the potential landslide hazard area. I. Surface and subsurface drainage should be designed to minimize impacts to the steep slope area. Based on relatively permeable soil over relatively impermeable soil present, we do not recommend infiltration systems within 50 feet of the potential landslide hazard area. 3. This geotechnical engineering study was prepared by a licensed engineer. a. Geotechnical design parameters are provided within this report. b. Drainage and subdrainage recommendations are provided within this report. Earth Solutions NW. LLC North Star Visions, LLC ES-8626.01 August 22, 2022 Page 9 Updated September 23, 2022 c. Earthwork recommendations are provided within this report. d. In our opinion, no slope stabilization measures are necessary and no seismically unstable soils were identified. G. It is our opinion the site erosion hazard areas should be considered stable. H. Based on the results of our study, the site does not contain any seismic hazard areas. Development Standards (General Requirements) — ECC 23.80.060 Based on the results of our geological hazards assessment, the proposed project will not increase the threat of the geological hazard to adjacent properties beyond predevelopment conditions, the proposed project will not adversely impact other critical areas, the proposed project is designed so that the hazard to the project is eliminated or mitigated to a level equal to or less than predevelopment conditions, and the project is certified as safe as designed under anticipated conditions. Development Standards (Specific Hazards) — ECC 23.80.070 1. We recommend the building be setback at least 10 feet from the face of the steep slope area (see Plate 3). 2. It is our opinion that a buffer is not necessary for the currently proposed project. 3. We understand the proposed project may include minimal alteration of the slope area to remove invasive vegetation groundcover and establish a native vegetation groundcover system. Provided the recommendations in this report and subsequent geotechnical recommendations are incorporated into the design and construction of the project, the proposed alteration will not increase surface water discharge or sedimentation to adjacent properties beyond predevelopment conditions, will not decrease slope stability on adjacent properties, and such alterations will not adversely impact other critical areas. 4. a. The proposed project will include lowering grades to the northeast of the slope area. In this respect, the proposed project will not decrease the factor of safety for the subject property or adjacent properties. b. It is our opinion that the structures and improvements have been located and engineered in a manner which sufficiently mitigates impacts to geologically hazardous areas. c. The proposed project is designed to minimize alterations to the natural contours of the site and will not alter grades of the steep slope area. Earth Solutions NW. LLC North Star Visions, LLC August 22, 2022 Updated September 23, 2022 ES-8626.01 Page 10 d. The structures and improvements have been located and engineered in a manner that retains the most critical portions of slope areas (southwest corner of the site) as well as natural landforms and vegetation. e. The proposed development will not result in greater risk or a need for increased buffers on neighboring properties. f. Based on the minimal construction, artificial alteration of the existing slopes will not be necessary. 5. We understand removal of invasive groundcover within the steep slope area is being considered, and would be replaced with native vegetation groundcover. 6. It is our opinion that this site should not be restricted to seasonal clearing and grading work. This opinion is based on the relatively small scope of the project and relatively low risk of erosion based on the proposed grading. However, if work is completed during wet weather, additional duration and cost should be anticipated to implement erosion control BMPs and mitigate negative impacts of runoff. 7. We are not aware of proposed point discharges. Temporary Excavations For temporary cuts taller than four feet, we recommend sloping or benching the cuts with a 1 H:1 V gradient. Steeper inclinations can be evaluated by ESNW during construction based on exposed soil conditions. Structural Fill Structural fill is defined as compacted soil placed in foundation, slab -on -grade, roadway, permanent slope, retaining wall, and utility trench backfill areas. Structural fill placed and compacted during site grading activities should meet the following specifications and guidelines: • Structural fill material • Moisture content • Relative compaction • Loose lift thickness (maximum) Granular soil* At or slightly above optimum 95 percent (Modified Proctor) 12 inches Existing soil may not be suitable for use as structural fill unless at (or slightly above) the optimum moisture content at the time of placement and compaction. ** Soil shall not be placed dry of optimum and should be evaluated by ESNW during construction. Earth Solutions NW. LLC North Star Visions, LLC August 22, 2022 Updated September 23, 2022 ES-8626.01 Page 11 With respect to underground utility installations and backfill, local jurisdictions may dictate the soil type(s) and compaction requirements. Unsuitable material or debris must be removed from structural areas if encountered. If structural fill is placed on sloped grades, the slope should be keyed and benched prior to placing fill. ESNW should review grading plans and provide additional recommendations as necessary. Foundations The proposed structure can be supported on conventional spread and continuous footings bearing on undisturbed, competent native soil, compacted native soil, or new structural fill. Competent native soils, suitable for support of the foundation, should be encountered beginning at depths of approximately one to three feet bgs. Where loose or unsuitable soil conditions are encountered at foundation subgrade elevations during site preparation activities, compaction of the soils to the specifications of structural fill, or overexcavation and replacement with granular structural fill will be necessary. Compaction of the soil to the levels necessary for use as structural fill may be difficult during wet weather conditions. Organic material exposed at foundation subgrade elevations must be removed and grades restored with structural fill. Provided the structure will be supported as described above, the following parameters can be used for design of the new foundations: • Allowable soil bearing capacity 2,500 psf • Passive earth pressure 300 pcf (equivalent fluid) • Coefficient of friction 0.40 The passive earth pressure and coefficient of friction values include a safety factor of 1.5. A one- third increase in the allowable soil bearing capacity can be assumed for short-term wind and seismic loading conditions. With structural loading as expected, total settlement in the range of one inch is anticipated, with differential settlement of about one-half inch. The majority of the settlements should occur during construction, as dead loads are applied. Slab -on -Grade Floors Slab -on -grade floors for the proposed residential structure should be supported on a well - compacted, firm, and unyielding subgrade. Where feasible, native soils exposed at the slab -on - grade subgrade level can likely be compacted in -situ to the specifications described in this section. Unstable or yielding areas of subgrade should be recompacted, or overexcavated and replaced with suitable structural fill, prior to construction of the slab. Earth Solutions NW. LLC North Star Visions, LLC August 22, 2022 Updated September 23, 2022 ES-8626.01 Page 12 A capillary break consisting of a minimum of four inches of free -draining crushed rock or gravel should be placed below the slab. The free -draining material should have a fines content of 5 percent or less (where the fines content is defined as the percent passing the Number 200 sieve, based on the minus three -quarter -inch fraction). In areas where slab moisture is undesirable, installation of a vapor barrier below the slab should be considered. If a vapor barrier is utilized, it should be a material specifically designed for use as a vapor barrier and should be installed in accordance with manufacturer specifications. Retaining Walls Retaining walls must be designed to resist earth pressures and applicable surcharge loads. The following parameters may be used for design: • Active earth pressure (unrestrained condition) • At -rest earth pressure (restrained condition) • Traffic surcharge (passenger vehicles) • Passive earth pressure • Coefficient of friction • Seismic surcharge Where applicable. ** Where H equals the retained height (in feet). 35 pcf (equivalent fluid) 55 pcf 70 psf (rectangular distribution) * 300 pcf (equivalent fluid) M1 8H psf** A factor -of -safety of 1.5 has been applied to the passive earth pressure and coefficient of friction values provided in this section. The above design parameters are based on a level backfill condition and level grade at the wall toe. Revised design values will be necessary if sloping grades are to be used above or below retaining walls. Additional surcharge loading from adjacent foundations, sloped backfill, or other relevant loads should be included in the retaining wall design. Retaining walls should be backfilled with free -draining material that extends along the height of the wall and a distance of at least 18 inches behind the wall. In lieu of 18 inches of a free draining material, a drainage mat can be considered. ESNW should evaluate the suitability of drainage mat application during construction. The upper 12 inches of the wall backfill may consist of a less permeable soil, if desired. A perforated drainpipe should be placed along the base of the wall and connected to an approved discharge location. A typical retaining wall drainage detail is provided on Plate 4. If drainage is not provided, hydrostatic pressures should be included in the wall design. Earth Solutions NW. LLC North Star Visions, LLC August 22, 2022 Updated September 23, 2022 Seismic Design ES-8626.01 Page 13 The 2018 International Building Code (2018 IBC) recognizes the most recent edition of the Minimum Design Loads for Buildings and Other Structures manual (ASCE 7-16) for seismic design, specifically with respect to earthquake loads. Based on the soil conditions encountered at the test pit locations, the parameters and values provided below are recommended for seismic design per the 2018 IBC. Parameter Value Site Class D* Mapped short period spectral response acceleration, Ss (g) 1.28 Mapped 1-second period spectral response acceleration, S1 (g) 0.449 Short period site coefficient, Fa 1.0 Long period site coefficient, F„ 1.851 ** Adjusted short period spectral response acceleration, SMs (g) 1.28 Adjusted 1-second period spectral response acceleration, SM1 (g) 0.831** Design short period spectral response acceleration, SIDS (g) 0.853 Design 1-second period spectral response acceleration, SD1 (g) 0.554** * Assumes dense native soil conditions, encountered to a maximum depth of 3.0 feet bgs during the May 2022 field exploration, remain dense to at least 100 feet bgs. ** Values assume Fv may be determined using linear interpolation per Table 11.4-2 in ASCE 7-16. Liquefaction Liquefaction is a phenomenon where saturated and loose cohesionless soil suddenly loses internal strength and behaves as a fluid. This behavior is in response to increased pore water pressures resulting from an earthquake or another intense ground shaking. In our opinion, site susceptibility to liquefaction may be considered low. The depth of the regional groundwater table, and the composition and relative density of the native soil were the primary bases for this opinion. Drainage Zones of perched groundwater seepage should be anticipated in site excavations depending on the time of year grading operations take place. Temporary measures to control surface water runoff and groundwater during construction would likely involve passive elements such as interceptor trenches and sumps. ESNW should be consulted during preliminary grading to identify areas of seepage and to provide recommendations to reduce the potential for instability related to seepage effects. Earth Solutions NW. LLC North Star Visions, LLC ES-8626.01 August 22, 2022 Page 14 Updated September 23, 2022 Finish grades should be designed to direct surface water away from structures and slopes. Grades adjacent to structures and slopes should be sloped away at a gradient of at least 2 percent for a horizontal distance of up to 10 feet or the maximum allowed by adjacent structures. In our opinion, foundation drains should be installed along building perimeter footings. A typical footing drain detail is provided on Plate 5. Rain Garden We understand a rain garden is proposed immediately northeast of the southwest slope area. We recommend installing an impermeable liner for the proposed rain garden. If an alternative rain garden location is considered or pursued, ESNW can reevaluate this recommendation. Infiltration and LID Evaluation As indicated in the Subsurface Conditions section, native soils encountered during our fieldwork were characterized primarily as dense coarse -grained soil. Based on the results of USDA textural analyses, the native soils at depth were classified primarily as gravelly loamy coarse sand and gravelly sandy loam with fines contents of about 10 to 12 percent at depth. While the dense coarse -grained site soil may exhibit a low infiltration capacity, infiltration should be considered infeasible due to the sloped topography along the west side of the property. Attempted infiltration would present reasonable concern of erosion and downgradient flooding. Limitations This geotechnical evaluation report has been prepared for the exclusive use of North Star Visions, LLC and their representatives. The recommendations and conclusions provided in this report are professional opinions consistent with the level of care and skill that is typical of other members in the profession currently practicing under similar conditions in this area. A warranty is not expressed or implied. Variations in the soil and groundwater conditions observed at the test sites may exist and may not become evident until construction. ESNW should reevaluate the conclusions in this report if variations are encountered. Additional Services ESNW should be retained to provide additional geotechnical services in association with this project, including testing and consulting services during construction. ESNW should have an opportunity to review final project plans with respect to geotechnical recommendations provided in this letter. Earth Solutions NW. LLC North Star Visions, LLC August 22, 2022 Updated September 23, 2022 ES-8626.01 Page 15 We trust this letter meets your current needs. Should you have questions, or if any additional information is required, please call. Sincerely, EARTH SOLUTIONS NW, LLC Adam Z. Shier, L.G. Project Geologist lT•WR� jo�W Asy,��y� , a 5 03 RFGISTER�� FSS/ONM- 09/23/2022 Henry T. Wright, P.E. Associate Principal Engineer Attachments: Plate 1 — Vicinity Map Plate 2 — Hand Auger Boring Location Plan Plate 3 — Foundations Adjacent to Slopes Plate 4 — Retaining Wall Drainage Detail Plate 5 — Footing Drain Detail Hand Auger Boring Logs Grain Size Distribution Earth Solutions NW. LLC / Forest e_ ?o\, = Wood_wdy o � � � s� �^ -_ - x _ \ 2''ist Street S 232nd Street Southwest p Holl a 9 0 3 ' EdmondsMap g e Nottingham Road a0 Macro = o Q 235[h Place Southwest - 3 j L � o � 0 d westd Snoline - c ' 23S[h Street Southwest , •� Elementdry I , 237th Place : esta 4 P I238th Southw 5[h001 �tl x f ^cu Street �■{yelp / I 3 ° � 240th Street Southwest T1 240[h Street Southwest awl W 3pe. Road < u G i. ory>ir West 45 I 1 SITEo?f F�: I a " _ Null dale _ Eagle Lane_ _.- - - ol Berry Lane P N243rd Place Soutt"N¢ ___ _ Woodway Snohomish County Edmonds' I King County ��• � Northwest 204thSe � I P. D eh D f o �o o a — p. Z m North 2021 T q j o z D l O p s �jthwest 201 st Street < c Nom I o .3 North 201 rthwest 201st Street n o m fD o Northwest 199th Street orthwest 200th Street ..D z = < aNNorth 200th Streetm o m m Northwest 198th Street 'l' .. .. Nor Northwest 198th Street t Northwest 197th Street .. '• North I z z 2� �rh D -- —Northwest 195th Street of Northwest 195th Street North 195th Street s H J Richmond P o ? s�\ 44 a t eBeach 4y aP D ` D \ h Albert Einstein ft o Middle .'. P < z c ? rthwes[' School < < o o Northwest 192nd Street o �� y f z %5 Northwest 190th Street I ,P'190th Street •. - P �� — — North 1 "let et •` -... �� .. 0 o C z Northwest 185th Street s` Blue Heron a'" �' 6p•. 4 Reserve So' D z o E �L. C j o• O. — D 1 Q s. rn h 3 _ 3 00 J�,N¢St D D 7 c j `C Q z D z s North t82n s a o z z SPtm9aa < m J O Z � � D Northwest 180th Street A, Reference: NORTHti r rth [NW Snohomish County, Washington 00! �16' Open StreetMap.org 1 NER.- 40 Vicinity Map Sugar and Scovill Property Edmonds, Washington NOTE: This plate may contain areas of color. ESNW cannot be Drwn. MRS Date 07/26/2022 Proj. No. 8626.01 responsible for any subsequent misinterpretation of the information Checked HTW Date July 2022 Plate 1 resulting from black & white reproductions of this plate. , I / � w / � I 400 / I / \ ' HA-3 I / HA7 — HA-2 400 El I I I I � I I � I I I � I I � I I 1 244TH STREET S.W. LEGEND HA-1 Approximate Location of — — ESNW Hand Auger Boring, Proj. No. ES-8626.01, May 2022 Subject Site Existing Building NOTE: The graphics shown on this plate are not intended for design purposes or precise scale measurements, but only to illustrate the approximate test locations relative to the approximate locations of existing and / or proposed site features. The information illustrated is largely based on data provided by the client at the time of our study. ESNW cannot be responsible for subsequent design changes or interpretation of the data by others. NOT - TO - SCALE Hand Auger Boring Location Plan Sugar and Scovill Property Edmonds, Washington NOTE: This plate may contain areas of color. ESNW cannot be Drwn. MRS Date 07/25/2022 Pro No. 8626.01 responsible for any subsequent misinterpretation of the information J resulting from black & white reproductions of this plate. Checked HTW Date July 2022 Plate 2 Foundations Adjacent to Slopes Sugar and Scovill Property Edmonds, Washington Drwn. MRS Date 09/22/2022 Proj. No. 8626.01 Checked HTW Date Sept. 2022 Plate 3 18" Min. 0 0 o 0 o O °o o �p � �° �0 .0 po o °o�0 0o0 ° ��o 0 �oo 0 0 0 00° 0000�oo 00000 o 0 0 0 0 oo .0 o, o 8 0 00 o o oo O 0 0 0 0 o o o o O o0 o oo op o° 0 o o 0 0 0 0 o 0 0 0 o0 00° 0 o o 00 0 op oo 0 o o o 0 0 0o Oo 0 0 Oo0o O oo o 00 00 0 0 oo o p o o�oo ...0. 00 0 0 8 0 0 0 0 oo 0 0 0 000 o0 o 000 o 0 0 0 g o Ooop o 0 0o 00 p o oo 0 0 o So o0 0 0 0 0 o 0 0 00 o o 00 0 000 8 Oo 0 & o p 0o0o o Oo .0 0 0�?, NOTES: • Free -draining Backfill should consist of soil having less than 5 percent fines. Percent passing No. 4 sieve should be 25 to 75 percent. • Sheet Drain may be feasible in lieu of Free -draining Backfill, per ESNW recommendations. • Drain Pipe should consist of perforated, rigid PVC Pipe surrounded with 1-inch Drain Rock. LEGEND: Q 00o O p o000 Free -draining Structural Backfill -inch Drain Rock %. of of of ti Structural Fill Perforated Rigid Drain Pipe (Surround in Drain Rock) SCHEMATIC ONLY - NOT TO SCALE NOT A CONSTRUCTION DRAWING Retaining Wall Drainage Detail Sugar and Scovill Property Edmonds, Washington Drwn. MRS Date 09/22/2022 Proj. No. 8626.01 Checked HTW Date Sept. 2022 1 Plate 4 Perforated Rigid Drain Pipe (Surround in Drain Rock) NOTES: • Do NOT tie roof downspouts to Footing Drain. • Surface Seal to consist of 12" of less permeable, suitable soil. Slope away from building. LEGEND: Surface Seal: native soil or other low -permeability material B.* - _- - - _... " - " 1-inch Drain Rock SCHEMATIC ONLY - NOT TO SCALE NOT A CONSTRUCTION DRAWING Earth Solutions NW uc Footing Drain Detail Sugar and Scovill Property Edmonds, Washington Drwn. MRS Date 09/22/2022 Proj. No. 8626.01 Checked HTW Date Sept. 2022 Plate 5 Earth Solutions NWLLC SOIL CLASSIFICATION CHART MAJOR DIVISIONS SYMBOLS TYPICAL DESCRIPTIONS GRAPH I LETTER GRAVEL AND CLEAN GRAVELS • �•• .� GW WELL -GRADED GRAVELS, GRAVEL - SAND MIXTURES, LITTLE OR NO FINES ° �a o �a o p�o p Q oQ GAP POORLY -GRADED GRAVELS, GRAVEL - SAND MIXTURES, LITTLE OR NO FINES GRAVELLY SOILS (LITTLE OR NO FINES) COARSE GRAINED SOILS MORE THAN 50% OF COARSE GRAVELS WITH FINES ° �0 00 D O GM SILTY GRAVELS, GRAVEL - SAND - SILT MIXTURES FRACTION RETAINED ON NO. 4 SIEVE (APPRECIABLE AMOUNT OF FINES) �±� V CLAYEY GRAVELS, GRAVEL - SAND - CLAY MIXTURES SAND AND CLEAN SANDS SW WELL -GRADED SANDS, GRAVELLY SANDS, LITTLE OR NO FINES MORE THAN 50% OF MATERIAL IS SP POORLY -GRADED SANDS, GRAVELLY SAND, LITTLE OR NO FINES LARGER THAN N0. 200 SIEVE SIZE SANDY SOILS (LITTLE OR NO FINES) SANDS WITH FINES c SM SILTY SANDS, SAND - SILT MIXTURES MORE THAN 50% OF COARSE FRACTION PASSING ON NO. 4 SIEVE (APPRECIABLE AMOUNT OF FINES) CC S CLAYEY SANDS, SAND - CLAY MIXTURES INORGANIC SILTS AND VERY FINE ML SANDS, ROCK FLOUR, SILTY OR CLAYEY FINE SANDS OR CLAYEY SILTS WITH SLIGHT PLASTICITY CL INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY, GRAVELLY CLAYS, SANDY CLAYS, SILTY CLAYS, LEAN CLAYS FINE GRAINED SOILS SILTS AND LIQUID LIMIT LESS THAN 50 CLAYS — — — OL ORGANIC SILTS AND ORGANIC SILTY CLAYS OF LOW PLASTICITY MORE THAN 50% OF MATERIAL IS SMALLER THAN NO. 200 SIEVE MH INORGANIC SILTS, MICACEOUS OR DIATOMACEOUS FINE SAND OR SILTY SOILS SIZE SILTS LIQUID LIMIT AND GREATER THAN 50 CLAYS CH INORGANIC CLAYS OF HIGH PLASTICITY OH ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY, ORGANIC SILTS HIGHLY ORGANIC SOILS PT PEAT, HUMUS, SWAMP SOILS WITH HIGH ORGANIC CONTENTS DUAL SYMBOLS are used to indicate borderline soil classifications. The discussion in the text of this report is necessary for a proper understanding of the nature of the material presented in the attached logs. r Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 BORING NUMBER HA-1 PAGE 1 OF 1 PROJECT NUMBER ES-8626.01 PROJECT NAME Sugar and Scovill Property DATE STARTED 5/11/22 COMPLETED 5/11/22 GROUND ELEVATION DRILLING CONTRACTOR ESNW Rep LATITUDE LONGITUDE LOGGED BY HTW CHECKED BY HTW GROUND WATER LEVEL: NOTES S7 AT TIME OF DRILLING SURFACE CONDITIONS Grass AFTER DRILLING w CL _ wJ ~W CO TESTS _ CL O d7 u/i Q W p Q Z 0 0.0 TPSL-.. - 0.5 o o ° - MC=9.1% ° GM ° ° 2.5 MC = 8.9% Fines = 12.1 % ° ° ° MATERIAL DESCRIPTION Dark brown gravelly TOPSOIL Brown silty GRAVEL with sand, loose to medium dense, moist to wet -trace fine to medium roots to BOH -becomes medium dense, light brown -becomes tan, dense, moist [USDA Classification: very gravelly sandy LOAM] Hand auger boring terminated at 3.0 feet below existing grade due to refusal on gravel. No groundwater encountered during excavation. No caving observed. LIMITATIONS: Ground elevation (if listed) is approximate; the test location was not surveyed. Coordinates are approximate and based on the WGS84 datum. Do not rely on this test log as a standalone document. Refer to the text of the geotechnical report for a complete understanding of subsurface conditions. r Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 BORING NUMBER HA-2 PAGE 1 OF 1 PROJECT NUMBER ES-8626.01 PROJECT NAME Sugar and Scovill Property DATE STARTED 5/11/22 COMPLETED 5/11/22 GROUND ELEVATION DRILLING CONTRACTOR ESNW Rep LATITUDE LONGITUDE LOGGED BY HTW CHECKED BY HTW GROUND WATER LEVEL: NOTES S7 AT TIME OF DRILLING SURFACE CONDITIONS Grass AFTER DRILLING w _ CL ~W _ wJ CO TESTS Q O MATERIAL DESCRIPTION p d7 fy Q Z 0 0.0 TPSL Dark brown gravelly TOPSOIL 0.5 SP- :'TT Gray poorly graded SAND with silt and gravel, dense to very dense, moist MC = 9.2% SM 1.0 -weakly cemented Fines = 10.5% [USDA Classification: very gravelly loamy coarse SAND] Hand auger boring terminated at 1.0 foot below existing grade due to refusal on cemented soil. No groundwater encountered during excavation. No caving observed. LIMITATIONS: Ground elevation (if listed) is approximate; the test location was not surveyed. Coordinates are approximate and based on the WGS84 datum. Do not rely on this test log as a standalone document. Refer to the text of the geotechnical report for a complete understanding of subsurface conditions. r Earth Solutions NW, LLC 15365 N.E. 90th Street, Suite 100 Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 BORING NUMBER HA-3 PAGE 1 OF 1 PROJECT NUMBER ES-8626.01 PROJECT NAME Sugar and Scovill Property DATE STARTED 5/11/22 COMPLETED 5/11/22 GROUND ELEVATION DRILLING CONTRACTOR ESNW Rep LATITUDE LONGITUDE LOGGED BY HTW CHECKED BY HTW GROUND WATER LEVEL: NOTES S7 AT TIME OF DRILLING SURFACE CONDITIONS Grass AFTER DRILLING w CL _ wJ ~W CO TESTS _ Q O MATERIAL DESCRIPTION QCL z 0 Dark brown gravelly TOPSOIL TPSL 0.5 ° Brown poorly graded GRAVEL with sand, loose to medium dense, moist to wet o ° GP oO� -becomes light brown, medium dense MC = 5.0% ° Fines = 4.7% o O -BOH probed dense 2.0 [USDA Classification: extremely gravelly coarse SAND] Hand auger boring terminated at 2.0 feet below existing grade due to refusal on gravel. No groundwater encountered during excavation. No caving observed. LIMITATIONS: Ground elevation (if listed) is approximate; the test location was not surveyed. Coordinates are approximate and based on the WGS84 datum. Do not rely on this test log as a standalone document. Refer to the text of the geotechnical report for a complete understanding of subsurface conditions. Earth Solutions NW, LLC GRAIN SIZE DISTRIBUTION 15365 N.E. 90th Street, Suite 100 WWI Redmond, Washington 98052 Telephone: 425-449-4704 Fax: 425-449-4711 PROJECT NUMBER ES-8626.01 PROJECT NAME Sugar and Scovill Property U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS I HYDROMETER 6 4 3 2 1 3/4 1 /23/8 3 4 6 810 1416 20 30 40 50 60 100140 200 100 95 90 85 80 75 70 65 H 60 w � 55 m w 50 z LL 45 z w 40 w a 35 30 25 20 15 10 5 0 Ll 100 10 1 0.1 0.01 0.001 GRAIN SIZE IN MILLIMETERS COBBLES GRAVEL SAND SILT OR CLAY coarse fine coarse medium fine 0 S w N z 9 0 Tara Beitler From: Henry Wright <henryw@esnw.com> Sent: Monday, July 31, 2023 6:27 PM To: Lucas Kragt Cc: Tara Beitler; Andy Reaves; Kevin Ballard Subject: Re: Sugar Site Hi Lucas, Yes, I agree with Jerry. Thank you, Henry T. Wright, P.E. Associate Principal Engineer Earth Solutions NW, LLC Phone: 425-449-4704 Cell: 206-793-4193 Email: henryw@esnw.com This e-mail is intended for the use of the individual to whom it is addressed and may contain information that is privileged, confidential or otherwise exempt from disclosure under applicable law. If the receiver of this e-mail is not the intended recipient or the employee or agent responsible for delivering the message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. On Jul 31, 2023, at 4:42 PM, Lucas Kragt <lucas@village-life.net> wrote: Hey Henry, Please see Jerry's response to my phone call regarding the footing drain. Are you ok with the drywell for footing drains only? Regards, Lucas Kragt, PE Engineering Manager 206.305.7271 Cell 425.678.1477 Office 19020 33rd Ave West, Suite 450 Lynnwood, WA 98036 <image002.png> 1 <image003.jpg> Like Us On Facebook! From: Shuster, Jerry <jerry.shuster@edmondswa.gov> Sent: Friday, July 28, 2023 10:40 To: Lucas Kragt <lucas@village-life.net> Subject: Sugar Site CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender and know the content is safe. Hi, Footing drains generally do not produce much flow. So, if your Geotech approves, a small drywell will work. The other option is to connect to the system downstream of the detention tank. Thanks GJwefx'00/1 Jerry Shuster, P.E. (he/him) Storm water Engineer City of Edmonds Public Works 121 Sth Ave N., Edmonds, WA 98020 Desk: 425.771.0220 x1323 Cell: 425.512.2597 Jerry.Shuster@edmondswa.eov