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Graphite Art Drainage Report_ApprovedC � ENGINEERING civil & structural engineering & planning DRAINAGE REPORT Graphite Art Studios 202 Main Street Edmonds, WA 98020 COMPLIES WITH APPLICABLE CITY ,.�.......... �_.. --DE ►7 �G GU1 L 1212712019 2SO4ch Ave S Ste 200 CG Project No.: 19144.20 Edmonds, WA 98020 Phone: {425]778-8500 Fax: (425) 778-SS36 Table of Contents Section I — Project Overview Section II — Off -Site Analysis Section III — Permanent Stormwater Control Plan Section IV —Construction Stormwater Pollution Prevention Plan Section V — Special Reports and/or Studies Section VI — Other Permits Section VII — Bond Quantities & Operation and Maintenance Manual C 4M 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 December 27, 2019 Drainage Report Section I, Page 1 Section I — Project Overview Section I Summary Overview Existing Condition Developed Condition Minimum Requirements Overview This drainage report has been written for a new building on a 0.33 ac lot located at 202 Main Street in Edmonds, WA (Tax Parcel Number: 00454800101300). The building will have a roof area of approximately 14,599 sf (0.33 ac), essentially the whole site. The development also consists of road and side walk improvements in the right-of-way. The site is currently undeveloped, but there was a building that was recently demolished that took up most of the site. The project will meet minimum requirements 1 through 9 of the 2014 Department of Ecology Stormwater Management Manual for Western Washington (herein referred to as the DOE Manual) and comply with those requirements as modified in the Edmonds Community Development Code Chapter 18.30 (herein referred to as ECDC 18.30) and the December 2016 Addendum to ECDC 18.30 (herein referred to as the Edmonds Stormwater Addendum). Existing Condition The site is currently undeveloped. The building that was demolished had a footprint of approximately 13,260 sf (0.30 ac) and it took up most of the parcel. Concrete sidewalk took up the rest of the parcel's area. The site soils primarily consist of Glacial Till, which is "dense to very dense, silty sand with some gravel to sand with silt and gravel" according to Zipper Geo Associates. More about the soils can be found in Section V in the Geotechnical Engineering Report by Zipper Geo Associates. The site sits at the SE corner of the intersection of 2nd Ave S and Main St in downtown Edmonds. The site is bordered by Main St on the north edge, 2nd Ave S on the west edge, a gravel parking lot on the south edge, and other buildings on the east edge. There is an existing asphalt alleyway that runs along the south and east edges of the site between the gravel parking lot and the other buildings. Storm and sewer utilities are located in 2nd Ave S and in the alleyway on the south edge of the building. Water utilities are in 2nd Ave S and Main St. The site slopes at approximately 4% from the northeast corner to the southwest corner. The site does not appear to take on any significant upstream flows. The site is located in the Puget Sound Piped Watershed. The existing impervious areas on -site are as follows: Roof: 13,260 sf (0.304 ac) Sidewalk: 1,018 sf (0.023 ad Total: 14,278 sf (0.327 ac) C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section I, Page 2 Developed Condition The project consists of the construction of an approximately 14,599 sf building that will take up the entire parcel due to roof overhangs. There will also be street and sidewalk improvements in the right-of- way. The total of new plus replaced impervious surface (including ROW) is 17,094 sf (0.392 ac). Disturbance will affect the entire site. The site will utilize a 60" detention pipe with a flow control structure under the slab of the proposed building. Most of runoff on -site will drain to the detention pipe through roof drains, then to a Type I catch basin near the alley on the south edge of the building, and finally to the public storm main in 2nd Ave S. The asphalt alleyway in the right-of-way on the east side of the proposed building will be overlaid, but the profile and cross-section will remain unchanged. Similarly, the south alleyway's profile and cross- section will remain unchanged, except where proposed catch basins are located such that either side of the alley will be sloped down to them. The proposed impervious areas (including ROW) are as follows: Roof: 14,599 sf (0.335 ac) ROW Sidewalk (not covered by roof): 2,075 sf (0.047 ac) ROW Road: 436 sf (0.010 ad Total: 17,110 sf (0.392 ac) The new and replaced pollution -generating impervious areas are as follows: ROW Road, Mod: 436 sf (0.010 ad Total: 436 sf (0.010 ac) C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section I, Page 3 4Q- 707 �09 V oti \. M716 71S ff �_ 716 j Total project area: 0.33 ac 7()l 771 777 tijq44,'� T Total hard surfaces: 0.33 ac { PGHS/PGIS: 0.01 ac Total disturbed area: 0.33 ac NRCS soil group: B 7' 0 7 -, 1DnJ7ECT SITE 11i LAMES ST 200 1 Figure 1-1. Vicinity map (from Edmonds GIS). C � 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 December 27, 2019 Drainage Report Section I, Page 4 Figure 1-2. Map with storm pipe material (from Edmonds GIS). C 4M 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 December 27, 2019 Drainage Report Section I, Page 5 �• PP4FJECT SITE, 4b �! N ` 49 Figure 1-3. Aerial Photograph (from Edmonds GIS). Minimum Requirements Stormwater requirements were determined per the Edmonds Stormwater Addendum, ECDC 18.30, and the DOE Manual. This report is based on the steps recommended in Chapter 7 of the Edmonds Stormwater Addendum and Section 3.1.7 of the DOE Manual. The project is classified as a Category 2 because it will result in more than 5,000 sf of new plus replaced hard surfaces. Following the flow chart in Figure 1-4, Minimum Requirements #1-9 will apply to all new and replaced hard surfaces. Minimum Requirement #1: Preparation of Stormwater Site Plans: The stormwater site plan consists of this report and the civil drawings, and is prepared in accordance with Chapter 3 of Volume 1 of the DOE Manual and the requirements in the Edmonds Stormwater Addendum. Minimum Requirement #2: Construction Stormwater Pollution Prevention Plan (SWPPP): The SWPPP shall include a narrative and drawings. The SWPPP narrative shall include documentation that addresses the 13 elements of Construction Stormwater Pollution Prevention. See Section IV and the civil drawings. C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 December 27, 2019 Drainage Report Section I, Page 6 Minimum Requirement #3: Source Control of Pollution: All known, available and reasonable source control BMPs must be required for all projects approved by the City. Mandatory Operational Source Control BMPs must be implemented by forming a pollution prevention team, good housekeeping practices, preventive maintenance, spill prevention and cleanup, employee training, inspections, and record keeping. See Section IV for a source control discussion and Section VII for source control guide sheets from the DOE Manual. Minimum Requirement #4: Preservation of Natural Drainage Systems and Outfalls: Natural drainage patterns shall be maintained, and discharges from the project site shall occur at the natural location, to the maximum extent practicable. The manner by which runoff is discharged from the project site must not cause a significant adverse impact to downstream receiving waters and down -gradient properties. All projects shall submit an off -site qualitative analysis. A qualitative analysis of the upstream and downstream system entering the site is presented in Section II. Minimum Requirement #5: On -Site Stormwater Management: The proposed project is classified as a Category 2 per the Edmonds Stormwater Addendum. However, since the site is located in a Puget Sound direct discharge area (per ECDC 18.30.060.D.5.b.iv), the project does not have to achieve the LID Performance Standard, nor consider bioretention, rain gardens, permeable pavement, or full dispersion. The project must evaluate an alternative list of BMPs and the Edmonds Way Specific Requirements if applicable. This is discussed in Section III. Minimum Requirement #6: Runoff Treatment: This requirement applies to the new plus replaced hard surfaces and the converted vegetated areas that will generate pollutants and be conveyed to the public storm system through stormwater runoff. The proposed roof is consistently called out to be coated with an inert, non -leachable enamel coating on civil, structural and architectural plans. Runoff treatment is not required because the project will result in less than 5,000 sf of new pollution -generating hard surfaces that are exposed to rainfall. Minimum Requirement #7: Flow Control: Projects must provide flow control to reduce the impacts of stormwater runoff from hard surfaces and land cover conversions. However, flow control is not required for projects located in the Puget Sound Piped Watershed or for projects that discharge directly to, or indirectly through the City's MS4 to Puget Sound. After conversations with the City, it was determined that detention should be implemented for this project per the "Edmonds Way specific requirements" (ECDC 18.30.060.D.5.iv.b) in order to account for varying high tide events that could become downstream problems (see Section II for Off -Site Analysis). Therefore, a detention pipe was designed for the site. See Section III for the Permanent Stormwater Control Plan and a more thorough discussion of the "Edmonds Way specific requirements". Minimum Requirement #8: Wetlands Protection: Not applicable. There are no wetlands located in the immediate vicinity of the site or the outfall into Puget Sound. C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section I, Page 7 Minimum Requirement #9: Operation and Maintenance: An operation and maintenance manual that is consistent with the provisions in Volume I and Volume V of the SWMMWW is required for proposed Stormwater Treatment and Flow Control BMPs/facilities. The party (or parties) responsible for maintenance and operation shall be identified in the operation and maintenance manual. For private facilities approved by the City, a copy of the operation and maintenance manual shall be retained on - site or within reasonable access to the site, and shall be transferred with the property to the owner. For public facilities, a copy of the operation and maintenance manual shall be retained in the appropriate department. A log of maintenance activity that indicates what actions were taken shall be kept and be available for inspection. C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section I, Page 8 Docsthe project result in 2,000 square fcct, or greater, of new plus rcpIaci-d hard surfacc area" OR Doc%the land dLsturbing activity total 7,000 square feet or greater? No Minimum RcquircmcnLs No. I through 5 apply Minimum Requircmcnt No. 2 applies Next Question Does the projcct 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 lanLNeaped areas? OR Convert 2.5 acres or more of native vegetation to pastu re? H es Is this a road relate project? All Minimum Requirements apply to the new and replaced Ye: hard surlaces and converled vegetation areas_ All Minimum Rcquirements apply to the new hard surfaces and convcrted vegetation areas. Tea Does the project acid 5,000 square feet or more of new hard surficcs? Yes Do new hard surfaces add 50%or more to the existing hard surfaces within the project limits? No He No No additional I rcquircments. Figure 1-4. Flow chart for determining requirements for development (Figure 3.1 in the Edmonds Stormwater Addendum). C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 December 27, 2019 Drainage Report Section II, Page 1 Section II — Off -Site Analysis Section II Summary Task 1 — Define and map the study area Task 2 — Review all available information of the study area Task 3 — Field inspect the area Task 4 - Describe the drainage system, and its existing and predicted problems Task 1— Define and map the study area An initial qualitative analysis shall document potential off -site impacts of stormwater discharges for each upstream drainage system entering a site, and each downstream drainage system leaving a site according to Section 6.2 of the Edmonds Stormwater Addendum. The downstream analysis shall extend from the project site to the receiving water, or up to one -quarter mile, whichever is less. Runoff from the site will enter the City public storm main in 2"d Ave S and will be conveyed about % mile away to its outfall into Puget Sound. The downstream flowpath is outlined below in Figure II-1 from the City GIS map. The site is located in the Puget Sound Piped Watershed. d -45 /NST i o PROJECT SITE PD7 o PDT 46 O h Q Q OUTFALL Qqo J2 o ry7- 2-11 �' ! 0 o o Q q ti O O PD7-17 .. O O O O PD7-15 o ♦ O kPD7-39 O O CD i. PD737 O U l) O $� O O O O n P07'47 O (3►� - ^ ° PD7-16 (P -41 (PD7-18 PD7-52 O p o o- �- 0 0 0.20 mi PD7-2,) 10* Q> PD7-59 PD7-25 O O > * PD7-3• o �J p o 4D m O 58 ■ o PD7-26 � ALDER ST Ui o On Figure II-1. Vicinity map showing stormwater flow path and distance to outfall (from Edmonds GIS). C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section II, Page 2 Task 2 — Review all available information on the study area Existing stormwater improvements were determined from the survey and the City GIS map. Runoff from the site will enter the 12" concrete main in 2nd Ave S where it will be conveyed south. The 12" main crosses James St and becomes an 18" concrete pipe upon exiting a manhole and continues on towards Dayton St. At Dayton St, the main becomes a 24" concrete pipe and turns west toward Puget Sound. The main becomes an 18" concrete pipe and then a 30" concrete pipe just before it discharges into Puget Sound. The point of discharge is in the northern most row of the marina. Task 3 — Field inspect the study area A site visit was done on the afternoon of November 17, 2017. The weather was cloudy and it had rained that day. From evaluating surrounding conditions, the site does not appear to take on significant upstream runoff. The project proposes to tie all roof drains to a detention pipe prior to connecting to the 12" concrete main in 2nd Ave S. Figure II-2 shows a picture near the SE corner of the site looking NW at the site. There was not much to be seen from the off -site walk since the conveyance system consists entirely of underground pipes and manholes. Figure II-2. Project site, looking towards the NW. C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 December 27, 2019 Drainage Report Section II, Page 3 Figure II-3. SW corner of site, looking west toward proposed connection to storm main in 2nd Ave S. Task 4 — Describe the drainage system, and its existing and predicted problems The site is located in the Puget Sound Piped Watershed. Normally, this project would be Flow Control exempt because it discharges directly to Puget Sound. However, it has been determined that flooding issues could arise during high tide events. Therefore, per conversations with the City, it was required that detention should be implemented on this project per the "Edmonds Way specific requirements" (ECDC 18.30.060.D.5.iv.b). The project proposes to route all runoff from the building to a detention pipe beneath the building and discharge to the public storm main in 2nd Ave S via a flow control structure and catch basin. To be conservative, the detention system has been designed with the new and replaced right-of-way areas included in the area contributing to the detention system (see Section III for more details). C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section III, Page 1 Section III — Permanent Stormwater Control Plan Section III Summary Narrative Feasibility Review WWHM2012 Report Detention Calculations Alley Capacity Check NnrrntivP This project is classified as a Category 2 per the Edmonds Stormwater Addendum because it results in 5,000 sf or more of new plus replaced hard surfaces. However, since the project is located in a Puget Sound direct discharge area, per ECDC 18.30.060.D.5.b.iv, the project does not have to achieve the LID Performance Standard, nor consider bioretention, rain gardens, permeable pavement, or full dispersion. The project must evaluate an alternative list of BMPs and the Edmonds Way Specific Requirements if applicable. See below. Runoff treatment is not required for this project (see Minimum Requirement #6 in Section 1). Feasibility Review The project must implement on -site stormwater management BMPs to the maximum extent feasible per Minimum Requirement #5. The following BMPs were evaluated per ECDC 18.30.060.D.5.b.iv.A for all new plus replaced hard surfaces and land disturbed: 1. Post -Construction Soil Quality & Depth in accordance with BMP T5.13 in Chapter 5 of Volume V of the SWMMWW will be used for all disturbed pervious areas. 2. Downspout Full Infiltration Systems (BMP T5.10A) are infeasible because of the "low permeability of the glacial till soils" (according to the Geotechnical Report by ZGA). Downspout Dispersion Systems (BMP T5.1013) and Perforated Stub -out Connections (BMP T5.10C) are infeasible because there is no room on -site for such systems. 3. Concentrated Flow Dispersion (BMP T5.11) and Sheet Flow Dispersion (BMP T5.12) are infeasible because there is no room on -site for dispersion systems. None of the above On -site Stormwater Management BMPs were determined to be feasible for this project. Therefore, per ECDC 18.30.060.D.5.b.iv.B, the project must meet the "Edmonds Way Specific Requirements". This requires that the post -development 10-year and 100-year recurrence interval peak flows do not exceed 0.25 and 0.45 cfs per acre of impervious surface area, respectively, for all project site runoff from unmanaged surfaces. WWHM 2012 was used to model the runoff and size a detention system for this project. A portion of the WWHM Report can be found on the following pages. C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section III, Page 2 WWHM2012 PROJECT REPORT Project Name: Graphite Art Studios Detention Pipe Site Name: Graphite Art Studios Site Address: 202 Main Street City Edmonds Report Date: 5/7/2019 MGS Regoin Puget East Data Start 1901/10/1 Data End : 2058/09/30 DOT Data Number: 02 Version Date: 2017/04/14 Version : 4.2.13 Low Flow Threshold for POC 1 : 50 Percent of the 2 Year High Flow Threshold for POC 1: 50 year PREDEVELOPED LAND USE Name : Basin 1 Bypass: No GroundWater: No Pervious Land Use acre A B, Forest, Flat .392 Pervious Total 0.392 Impervious Land Use acre Impervious Total 0 Basin Total 0.392 Element Flows To: Surface Interflow MITIGATED LAND USE Name . Basin 1 Bypass: No GroundWater: No Pervious Land Use Pervious Total acre 0 Groundwater C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section III, Page 3 Impervious Land Use acre ROOF TOPS FLAT 0.392 Impervious Total 0.392 Basin Total 0.392 Element Flows To: Surface Interflow Tank 1 Tank 1 Name : Tank 1 Tank Name: Tank 1 Groundwater Depth: 5 ft. Tank Type Circular Diameter 5 ft. Length : 27 ft. Discharge Structure Riser Height: 4.95 ft. Riser Diameter: 18 in. Orifice 1 Diameter: 1.2 in. Elevation: 0.5 ft. Element Flows To: Outlet 1 Outlet 2 ANALYSIS RESULTS Stream Protection Duration Predeveloped Landuse Totals for POC #1 Total Pervious Area:0.392 Total Impervious Area:O Mitigated Landuse Totals for POC #1 Total Pervious Area:O Total Impervious Area:0.392 Flow Frequency Return Periods for Predeveloped Return Period Flow(cfs) 2 year 0.000072 5 year 0.000083 10 year 0.00009 25 year 0.0001 50 year 0.000107 100 year 0.000114 C � ENGINEERING POC #1 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 December 27, 2019 Drainage Report Section III, Page 4 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.062619 5 year 0.082659 10 year 0.097923 < 0.0980 cfs 25 year 0.119599 50 year 0.137576 100 year 0.157205 < 0.1764 cfs The development has an increase in flow durations from 1/2 Predeveloped 2 year flow to the 2 year flow or more than a 10% increase from the 2 year to the 50 year flow. The development has an increase in flow durations for more than 50% of the flows for the range of the duration analysis. Perind and Impind Changes No changes have been made. This program and accompanying documentation are provided 'as -is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by End User. Clear Creek Solutions Inc. and the governmental licensee or sublicensees disclaim all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall Clear Creek Solutions Inc. be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the like) arising out of the use of, or inability to use this program even if Clear Creek Solutions Inc. or their authorized representatives have been advised of the possibility of such damages. Software Copyright © by Clear Creek Solutions, Inc. 2005-2019; All Rights Reserved. Detention Calculations WWHM 2012 was used to model the project and design the detention pipe. Two WWHM models were run to simulate the project: one with only on -site areas (Basin 1) and another with on -site areas including right-of-way improvements (Basin 2). Basin 2 was made to see how the detention pipe's length would change with the additional area. Both basins were modeled using the proposed roof as the on - site area since the roof overhangs cover the whole lot. Basin 2 produced a longer detention pipe compared to Basin 1 (27' compared to 24'). The longer detention pipe was chosen for this project to be conservative for the design even though runoff from the ROW areas is not expected to contribute to the detention pipe. As was stated before, the post -development 10-year and 100-year recurrence interval peak flows are not to exceed 0.25 and 0.45 cfs per acre of impervious surface area, respectively, for all project site runoff from unmanaged surfaces (see calculations below). As can be seen in the WWHM Report above, the detention pipe has been designed to the parameters of the project and the "Edmonds Way specific requirements". 0.25 cfs 10 — year peak flow = * 0.392 acres = 0.0980 cfs 1 acre 0.45 cfs 100 — year peak flow = * 0.392 acres = 0.1764 cfs 1 acre C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 December 27, 2019 Drainage Report Section III, Page 5 Alley Capacity Check There is an existing 8" concrete stom line running through the alley from 3rd Ave S to 2nd Ave S. The pipe will be cut at the location of the proposed CB #4 (see civil plans) and will be an inlet to that catch basin. To determine the existing capacity of the pipe, the City of Edmonds GIS website was used with "Contour Lines" and "Stormwater" layers on. The pipes in question are pipes #4791 and #4792. Those pipes run between MH 7-5 and MH 7-6. Based on the GIS Map, and used in conjunction with the site survey, pipe #4792 has an existing slope of about 6.1% and pipe #4791 has a slope of about 5.1%. Therefore, pipe #4792 would be a more conservative check since it has a greater slope and, therefore, greater capacity. The GIS Map shows MH 7-5 at elevation 49.5 with the invert being 3.5 feet down (IE = 46.0). CB 7-393 has an IE of 33.63. So there is 12.37' of fall between the two structures and they are about 204 If apart. Therefore, the existing 8" concrete pipe has about a 6.1% slope, which corresponds to 3.29 cfs capacity (see Figure III-1 on the following page for conveyance capacity table). The proposed system consists of 12" PVC sloping at 3.5%, which corresponds to 7.89 cfs (see Figure III-2). The proposed system provides more than double the capacity of the existing system. Therefore, the alley's storm capacity is being improved as a result of the proposed development. C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section III, Page 6 Conveyance Capacity Table for: Graphite :art Alley Existing 8" Concrete Pipe 1.49 2 1 n= 0.012 Manning's Equation = Q = n *A*R3 *Sl Conveyance Capacity (cfs) 4-inch I 6-inch 10-inch I 12-inch 18-inch Slope (ftlft) 0.005 0.15 0.43 0.94 1.68 2.74 8.07 0.010 0.21 0.61 1.33 2.38 3.87 11.41 0.015 0.25 0.75 1.63 2.91 4.74 13.97 0.020 0.29 0.86 1.88 3.37 5.47 16.14 0.025 0.331 0.96 2.10 3.76 6.12 18.04 0.030 0.36 1.05 2.30 4.12 6.70 19.76 0.035 0.39 1.14 2.49 4.45 7.24 21.35 0.040 0.41 1.22 2.66 4.76 7.74 22.82 0.045 0.44 1.29 2.821 5.05 8.21 24.20 0.050 0.46 1.36 2.97 5.32 8.65 25.51 0.055 0.48 1.43 3.12 5.58 9.07 26.76 0.51 1.50 5.88 9.55 28.18 0.065 0.53 1.55 3.39 6.07 9.86 29.09 0.070 0.55 1.61 3.52 6.301 10.23 30.19 0.075 0.57 1.67 3.64 6.52 10.59 31.25 0.080 0.58 1.72 3.76 6.73 10.94 32.27 0.085 0.60 1.77 3.88 6.94 11.28 33.26 0.090 0.621 1.831 3.99 7.14 11.60 34.23 0.095 0.6,41 1.881 4.101 7.341 11.92 35.17 0.100 0.651 1.921 4.211 7.531 12.231 36.08 C � Conveyance Capacity B` TAF D°`' 11 26 2019 ENGINEERING Mannin 's EquationSca 250 4th Ave. South Conveyance Pipe in Alley le N.T.S. s*°°``O Suite 200 No Edmonds. NVA 98020 Graphite Art Studios 19144.20 Figure III-1. Conveyance capacity of concrete pipe for various sizes and slopes. C � 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section 111, Page 7 Conveyance Capacity Table for: Graphite :art Alley Proposed 12" PVC Pipe 1.49 2 1 n= 0.011 Manning's Equation = Q = n *A*R3 *Sl Conveyance Capacity (cfs) 4-inch I 6-inch 8-inch 10-inch 11111M 18-inch Slope (ftlft) 0.005 0.16 0.47 1.03 1.84 2.98 8.80 0.010 0.23 0.66 1.45 2.60 4.22 12.45 0.015 0.28 0.81 1.78 3.18 5.17 15.24 0.020 0.32 0.94 2.05 3.67 5.971 17.60 0.0251 0.361 1.05 2.29 4.11 6.67 19.68 0.030 0.39 1.15 2.51 4.50 7.31 21.56 0.42 1.24 2.71 4.86 23.29 0.040 0.45 1.33 2.90 5.19 8.44 24.89 0.045 0.48 1.41 3.08 5.51 8.95 26.40 0.050 0.501 1.48 3.24 5.81 9.44 27.83 0.055 0.53 1.56 3.40 6.09 9.90 29.19 0.060 0.55 1.63 3.55 6.36 10.34 30.49 0.065 0.57 1.69 3.70 6.62 10.76 31.73 0.070 0.60 1.76 3.841 6.87 11.16 32.93 0.075 0.621 1.82 3.97 7.11 11.56 34.09 0.080 0.6,41 1.88 4.10 7.34 11.94 35.20 0.085 0.661 1.94 4.23 7.57 12.301 36.29 0.090 0.68 1.99 4.35 7.79 12.66 37.34 0.095 0.69 2.05 4 ' 471 8.00 13.01 38.36 0.100 0.711 2.10 4.591 8.21 13.34 39.36 C Conveyance Capacity B` T.4F D°`' 11 26 2019 ENGINEERING Mannin 's EquationSca 250 4th Ave. South Conveyance Pipe in Alley le N.T.S. s*°°``O Suite 200 No Edmonds. «:4 98020 Graphite Art Studios 19144.20 Figure III-2. Conveyance capacity of PVC pipe for various sizes and slopes. C � 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 December 27, 2019 Drainage Report Section IV, Page 1 Section IV — Construction Stormwater Pollution Prevention Plan Section IV Summary: Narrative Erosion control details are provided consistent with the City of Edmonds guidelines. Erosion control plan sheets are provided in full-size as a part of the civil drawing set. For sites under one acre in area, the Department of Ecology (DOE) does not require completion of the full Construction SWPPP or the Construction Stormwater General Permit. Therefore, a Construction SWPPP is not required for this site. The following is an abbreviated format of the SWPPP that addresses each of the 13 elements of construction pollution prevention for the City review. Please note that the project may apply for a DOE permit regardless due to the contaminated soil considerations. Zipper Geo Associates has prepared an additional document for the project, an Environmental Media Management Plan (EMMP) dated May 11, 2018. This report details the nature and extent of the site impacts. It provides several recommendations throughout the report for excavations, stockpiling, loading, etc. in addition to these SWPPP requirements (not included with this submittal, City has on file). Element 1: Mark clearing limits To protect adjacent properties and to reduce the area of soil exposed to construction, the limits of construction will be clearly marked before land -disturbing activities begin. Clearing limits will be to the extents of necessary land disturbance for the new building and this can be seen on drawing sheet C2.1. The BMPs relevant to marking the clearing limits that will be applied for this project include: High Visibility Plastic or Metal Fence (BMP C103) Element 2: Establish construction access Construction access or activities occurring on unpaved areas shall be minimized, yet where necessary, access points shall be stabilized to minimize the tracking of sediment onto public roads. A stabilized construction entrance should be utilized as needed when possible to prevent sediment tracking. See C2.1 for placement. The BMPs relevant to establishing construction access that will be applied for this project include: Stabilized Construction Entrance (BMP C105) Element 3: Control Flow Rates The site slopes on average about 4% from east to west. The site is small enough that a silt fence used for Element 4 may be used to control flow rates. C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section IV, Page 2 Element 4: Install sediment controls All stormwater runoff from disturbed areas shall pass through an appropriate sediment removal BMP before leaving the construction site or prior to being discharged. Silt fences will be installed on the downstream ends. Pollution prevention facilities on the erosion control plan must be constructed prior to or in conjunction with all clearing and grading so as to ensure that the transport of sediment to surface waters and adjacent properties is minimized. The specific BMPs to be used for controlling sediment on this project include: Silt Fence (BMP C233) Element 5: Stabilize Soils Exposed and unworked soils shall be stabilized with the application of effective BMPs to prevent erosion throughout the life of the project. The specific BMPs for soil stabilization that shall be used on this project include: Temporary and Permanent Seeding (BMP C120) Mulching (BMP C121) Nets and Blankets (BMP C122) Plastic Covering (BMP C123) Sodding (BMP C124) Topsoil ing/Composting (BMP C125) Surface Roughening (BMP C130) Dust Control (BMP C140) Element 6: Protect Slopes There are existing surfaces that will be removed as part of the development. Exposed slopes shall be stabilized with BMPs found in Element 5. Element 7: Protect Drain Inlets Catch basins along Main St and 2nd Ave S and as made operable on -site will be protected from sedimentation. Stormwater shall not enter the conveyance system without first being filtered or treated to remove sediment. Inlet protection devices shall be cleaned or removed and replaced when sediment has filled one-third of the available storage (or as specified by the manufacturer). The specific BMPs to be used for protecting drain inlets are: Storm Drain Inlet Protection (BMP C220) Element 8: Stabilize Channels and Outlets Conveyance channels are not located on or in the immediate vicinity of the site. C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section IV, Page 3 Element 9: Control Pollutants Design, install, implement and maintain effective pollution prevention measures to minimize the discharge of pollutants. The suggested BMPs are: Concrete Handling (BMP C151) Sawcutting and Surfacing Pollution Prevention (BMP C152) Material Delivery, Storage and Containment (BMP C153) For this site, controlling the pollutants will also require strict compliance with the EMMP for the project. Section 10 of the EMMP lists requirements and recommendations for several different construction activities. Element 10: Control Dewatering De -watering is not anticipated, but if needed, should follow the EMMP. Element 11: Maintain BMPs All temporary and permanent erosion and sediment control BMPs shall be maintained and repaired as needed to ensure continued performance of their intended function. Element 12: Manage the Project • Phase development projects to the maximum degree practicable and take into account seasonal work limits. • Follow the recommendations and requirements of the EMMP. • Inspection and monitoring — Inspect, maintain, and repair all BMPs as needed to assure continued performance of their intended function. Conduct site inspections and monitoring in accordance with the Construction Stormwater General Permit or local plan approval authority. • Maintain an Updated Construction SWPPP - This SWPPP shall be retained on -site or within reasonable access to the site. - The SWPPP shall be modified whenever there is a change in the design, construction, operation, or maintenance at the construction site that has, or could have, a significant effect on the discharge of pollutants to waters of the state. - The SWPPP shall be modified if, during inspections or investigations conducted by the owner/operator, or the applicable local or state regulatory authority, it is determined that the SWPPP is ineffective in eliminating or significantly minimizing pollutants in stormwater discharges from the site. The SWPPP shall be modified as necessary to include additional or modified BMPs designed to correct problems identified. Revisions to the SWPPP shall be completed within seven (7) days following the inspection. Element 13: Protect Low Impact Development BMPs Low -Impact Development BMPs are not proposed for this project. C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section IV, Page 4 Source Controls This project should incorporate required BMPs from Volume IV of the DOE Manual: S407 — BMPs for Dust Control at Disturbed Land Areas and Unpaved Roadways and Parking Lots; S411— BMPs for Landscaping and Lawn/Vegetation Management; S417 — BMPs for Maintenance of Stormwater Drainage and Treatment Systems; and S424 — BMPs for Roof/Building Drains at Manufacturing and Commercial Buildings. The Operation & Maintenance Manual found in Section VII contains guide sheets for the aforementioned BMPs. C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section V, Page 1 Section V — Special Reports and/or Studies Section V Summarv: Narrative The following reports are included in this section: 1. Geotechnical Engineering Report by ZipperGeo, Geoprofessional Consultants dated November 21, 2017. 2. Natural Resources Conservation Service Soil Map dated November 14, 2017. C � 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com GEOTECHNICAL ENGINEERING REPORT MAR-VEL MARBLE REDEVELOPMENT 202 MAIN STREET EDMONDS, WASHINGTON Project No. 1798.01 November 21, 2017 Prepared for: Mary Olsen Prepared by: ZipperGeo Geoprofessional Consultants 19019 36th Ave West, Suite E I Lynnwood, WA 98036 1 Phone: 425.582.9928 1 zippergeo.com Zipp Geo Geoprofessional Consultants Mary Olsen 16550 7611 Avenue West Edmonds, Washington 98026 Subject: Geotechnical Engineering Report Mar-Vel Marble Redevelopment 202 Main Street Edmonds, Washington Dear Ms. Olsen, Project Number 1798.01 November 21, 2017 In accordance with your request and written authorization, Zipper Geo Associates, LLC (ZGA) has completed the subsurface exploration and geotechnical engineering evaluation for the proposed Mar-Vel Marble Redevelopment project at 202 Main Street in Edmonds, Washington. This report presents the findings of the subsurface exploration and our geotechnical recommendations for the project. Our services were completed in general accordance with our Proposal for Geotechnical Engineering Services (Proposal No. P16278A) dated March 28, 2017. Written authorization to proceed was provided by you on March 28, 2017. In addition to the services presented in proposal P16278A, ZGA also installed groundwater monitoring wells in the geotechnical borings, as authorized by you at the time of exploration. We appreciate the opportunity to be of service to you on this project. If you have any questions concerning this report, or if we may be of further service, please contact us. Sincerely, Zipper Geo Associates LLC o w�shj� 11121117 f� 0 mow' 1783 4• 00 d G60�o JAMES P. GEORGiS James P. Georgis, L.E.G. Principal Copies: Addressee (1) 19019 3611 Avenue West, Suite E Lynnwood, WA 98036 Thomas A. Jones, P.E. Principal (425) 582-9928 TABLE OF CONTENTS INTRODUCTION....................................................................................................................... 1 SITEDESCRIPTION.................................................................................................................. 1 PROJECT UNDERSTANDING.................................................................................................. 2 ENVIRONMENTAL CONSIDERATIONS................................................................................... 2 SUBSURFACE CONDITIONS................................................................................................... 3 PublishedGeologic Mapping.................................................................................................. 3 SoilConditions....................................................................................................................... 3 GroundwaterConditions......................................................................................................... 5 FieldScreening for VOCs....................................................................................................... 6 Geotechnical Laboratory Testing............................................................................................ 7 CONCLUSIONS AND RECOMMENDATIONS........................................................................... 7 GeneralConsiderations.......................................................................................................... 7 Seismic Considerations.......................................................................................................... 8 SitePreparation...................................................................................................................... 9 Structural Fill Materials and Placement..................................................................................11 Utility Trenching and Backfilling.............................................................................................13 Temporary and Permanent Slopes........................................................................................14 Temporary Soldier Pile Shoring.............................................................................................15 ShallowFoundations.............................................................................................................18 Permanent Retaining Walls...................................................................................................19 Slab -on -Grade Floors............................................................................................................20 Drainage Considerations.......................................................................................................21 CLOSURE................................................................................................................................22 FIGURES Figure 1 — Vicinity Map and Legend Figure 2 — Site and Exploration Plan Figure 3 — Generalized Geologic Cross Section A -A' Figure 4 — Lateral Earth Pressures, Temporary Soldier Pile Wall Figure 5 — Lateral Earth Pressures for Surcharge Loads APPENDICES Appendix A — Subsurface Exploration Procedures and Logs Appendix B — Laboratory Testing Procedures and Results GEOTECHNICAL ENGINEERING REPORT MAR-VEL MARBLE REDEVELOPMENT 202 MAIN STREET EDMONDS, WASHINGTON Project No. 1798.01 November 21, 2017 INTRODUCTION This report documents the surface and subsurface conditions encountered at the site and our geotechnical engineering recommendations for the proposed Mar-Vel Marble Redevelopment project located at 202 Main Street in Edmonds, Washington. The project description, site conditions, and our geotechnical conclusions and design recommendations are presented in the text of this report. Supporting data including detailed exploration logs, field exploration procedures, results of laboratory testing, and other supporting information are presented as appendices. Our geotechnical engineering scope of services for the project included a site reconnaissance, subsurface evaluation, laboratory testing, geotechnical analysis, and preparation of this report. The subsurface evaluation completed for this study included two exploratory borings (B-1/MW-1 and B-2/MW-2) located near the northwest corner and south-central side of the site. Borings B-1 and B-2 extended to respective depths of approximately 35 feet below the existing ground surface. ZGA competed additional borings (B-3/MW-3 through B-9/MW-9) and test pit explorations (TP-1A through TP-4) as part of a Phase II environmental evaluation of the site. These additional explorations have been incorporated into this report. SITE DESCRIPTION The project site is located at 202 Main Street in Edmonds, Washington. The site is bordered to the north by Main Street, to the west by 2nd Avenue South, to the east by an existing alley with commercial buildings further east, and to the south by an existing alley with a gravel parking lot further south. The approximate site location is shown on the enclosed Vicinity Map and Legend, Figure 1. The site supported three conjoined commercial buildings at the time the geotechnical filed investigation (borings B-1/MW-1 and B-2/MW-2) were completed. In general, the three conjoined buildings were constructed along the property lines (zero lot line setback) with the exception of a triangular open -space near the northwest corner of the site and a loading area on the north side of the southern alley. The buildings were one-story with slab -on -grade concrete floors and were reportedly supported on shallow foundations. Prior to ZGA's environmental evaluation of the site, the existing buildings were substantially demolished. Exterior grades around the site slope gently west with a total relief of about 8 feet across the site. The site is generally devoid of vegetation. An existing closed -in -place Underground Storage Tank (UST) is reportedly located below the sidewalk between 2nd Avenue South and the existing site buildings. ZipperGeo Gevprofessional Consultants PROJECT UNDERSTANDING Mar-Vel Marble Redevelopment Project No. 1798.01 November 21, 2017 We understand the project includes demolition of the existing buildings and construction of a new two-story, mixed -use building with one level of underground parking. We understand that the new development will have roughly the same footprint as the existing structures (about a 1-foot lot -line setback with a few portions of the building set back about 3 to 4 feet). We understand that the new building will utilize shallow foundations with a slab -on -grade parking level concrete floor. Preliminary plans indicate that the below grade parking level and access ramp will be located below the central and western portion of the building with parking level finished floor elevations ranging from about 32.7 to 31 feet. These parking level finished floor elevations are about 5 to 11 feet below existing exterior grades and we anticipate that excavations for foundation elements may extend about 11/2 to 2 feet deeper for anticipated construction excavation depths of 7 to 13 feet. The eastern 25 feet of the building does not include parking and includes a below grade utility room with a finished floor elevation of 37 feet and a 5-foot diameter stormwater detention pipe with an invert elevation of about 30 feet. The utility room finished floor elevations are about 5 to 7 feet below existing exterior grades and we anticipate that excavations for foundation elements may extend about 1'/2 to 2 feet below the finished floor elevation for anticipated construction excavation depths of 7 to 9 feet, with deeper excavations for the detention pipe. We understand that removal of the offsite closed -in -place underground storage tank is not included in the current development plan, but may be added at a later date depending on City of Edmonds requirements. The proposed development and parking level layout are shown on the enclosed Site and Exploration Plan, Figure 1. ENVIRONMENTAL CONSIDERATIONS The site and nearby vicinity have a documented history of environmental conditions. Environmental documents provided for our review indicate the following. • One 1,000-gallon heating oil underground storage tank (UST) was removed from the site. • One below grade hydraulic hoist was removed from the site. • One 1,000-gallon gasoline UST was removed from the off -site gravel parking lot located south of the site. • One 3,000-gallon gasoline off -site UST was closed -in -place below the sidewalk adjacent to the west side of the site. • Approximately 50 tons of petroleum contaminated soil (PCS) was removed from the site, thermally treated, and disposed of offsite. • Approximately 13 tons of PCS was removed from the off -site closed -in -place UST located below the sidewalk adjacent to the west side of the site, thermally treated, and disposed of offsite. • Approximately 131 tons of PCS was removed from the off -site gravel parking lot located south of the site, thermally treated, and disposed of offsite. • Petroleum contaminated soils were reportedly present on site at the time of previous remedial actions above MTCA Method A cleanup levels (Chapter 173-340 WAC). Page 2 Z i ppe rG eo Mar-Vel Marble Redevelopment Gevprofessional Consultants Project No. 1798.01 November21, 2017 • According to the documents, soils exceeding the cleanup standards were not able to be excavated at the time of remedial action and remain in place. • Groundwater was not evaluated from an environmental perspective before, during, or following remedial action. We understand that geotechnical recommendations are needed at this time to move forward with project design and are provided in this report. ZGA has been authorized by the owner to complete a Phase I Environmental Site Assessment (ESA) and a Focused Subsurface Investigation. These environmental services are underway and will be submitted under separate cover. This geotechnical report includes subsurface boring and test pit logs completed as part of our Focused Subsurface Investigation. SUBSURFACE CONDITIONS Published Geologic Mapping We assessed the geologic setting of the site and surrounding vicinity by reviewing the Geologic Map of the Edmonds East and Part of the Edmonds West Quadrangles, Washington, U.S. Geological Survey Map MF-1541, 1983. The geologic map indicates that the site is underlain by Quaternary Whidbey Formation (Qw) deposits. The Whidbey Formation is generally described as bedded, compact, medium -to -course grained sand with variable silt and gravel content and intermittent peat deposits in the upper portion of the unit. Soil Conditions The subsurface evaluation completed for this project included two borings (B-1/MW-1 and B- 2/MW-2) completed near the south-central side of the site and northwest corner of the site, respectively. Both borings extended to a depth of about 35 feet below grade. ZGA completed additional borings and test pit explorations as part of a Phase II environmental evaluation of the site, which have been incorporated into this report. Phase II borings B-3/MW-3 through B-9/MW-9 extended to depths ranging from about 21 to 28'/2 feet below grade. Test pits TP-1A through TP-4 extended to depths ranging from about 3'/2 to 18 feet below grade. Approximate exploration locations are shown on the enclosed Site and Exploration Plan, Figure 1. Soils were visually classified in general accordance with the Unified Soil Classification System. Detailed, descriptive logs of the subsurface explorations and the procedures utilized in the subsurface exploration program are presented in Appendix A. Stratification boundaries on the boring logs represent the approximate depth of changes in soil types, although the transition between materials may have been gradual. The soil types observed in our borings were relatively consistent, but may vary at other locations given limitations to site access for exploration purposes at the time this report was prepared. The nature and extent of variations may not become evident until construction. If variations become apparent during construction, it may be necessary to reevaluate the recommendations of this report. Page 3 Z i ppe rG eo Mar-Vel Marble Redevelopment Gevprofessional Consultants Project No. 1798.01 November 21, 2017 Generalized descriptions of subsurface soil conditions observed at the exploration locations are presented below. A generalized cross section through the site presenting our interpretation of the subsurface conditions is presented in the enclosed Generalized Cross Section A - A; Figure 3. Please refer to the boring logs in Appendix A for a more detailed description of the conditions encountered at the exploration locations. In general, the explorations encountered concrete pavement/sidewalk over fill soils. Below the fill, native deposits interpreted as weathered glacial till, over glacial till, over glacial advance outwash deposits were encountered. The following table presented a summary stratigraphy of the soils encountered in the exploration followed by a summary description of each soil unit. Summary of Subsurface Conditions Exploration Approx. Ground Surface Elevation 1(ft) Approximate Depth Interval of Soil Unit in Feet Total Depth Explored (ft) Concret a Existing Fill Weathered Glacial Till Glacial Till Glacial Advance Outwash B-1/MW-1 40.88 0 to %2 % to 3% 3%2 to 11 11 to 27 27 to 35 35 B-2/MW-2 39.51 0 to %: % to 3% --- 3%2 to 24 24 to 35 35 B-3/MW-3 41.00 --- --- 0 to 4 4 to 26 26 to 36% 36%: B-4/MW-4 41.32 --- --- --- 0 to 27% 27% to 36% 36% B-5/MW-5 41.20 --- --- 0 to 4 4 to 21% --- 21% B-6/MW-6 39.17 --- --- 0 to 4 4 to 30 30 to 38% 38% B-7/MW-7 39.08 --- --- 0 to 5 5 to 21 --- 21 B-8/MW-8 42.62 --- 0 to 5 --- 5 to 21% --- 21% B-9/MW-9 40.82 --- --- 0 to 5%: 5% to 21%: --- 21% TP-1A 38 --- --- 0 to 3 3 to 18 --- 18 TP-1B 38 --- --- 0 to 3 3 to 12 --- 12 TP-2A 40 --- 0 to 5% --- 5% to 10% --- 10% TP-2B 40 --- 0 to 5%2 --- 5%2 to 10%2 --- 10% TP-3 38 --- --- 0 to 3%2 --- --- 3% TP-4 43 --- --- 0 to 1% 1%2 to 16%2 --- 16%2 1. Ground surface elevations for borings B-1/MW-1 through B-9/MW-9 are based on groundwater monitoring well top of monument elevations provided by Pacific Coast Surveys, Inc. Ground surface elevations for test its TP-IA through TP-4 were interpolated from topographic contour lines presented on Figure 2. Existing Concrete Pavement: Borings B-1/MW-1 and B-2/MW-2 were completed through holes cored in existing concrete pavement. The concrete pavement ranged from about 5 to 6 inches thick. Crushed rock was not present below the concrete at the exploration locations. Existing Fill: In general, existing fill soils encountered in the explorations consisted of loose to medium dense, silty sand with some gravel. Former UST cavity backfill was encountered in a portion of test pits TP-2A and TP-213 and consisted of pea gravel. Page 4 Z i ppe rG eo Mar-Vel Marble Redevelopment Gevprofessivnal Consultants Project No. 1798.01 November 21, 2017 Weathered Glacial Till Deposits: Soils interpreted as weathered glacial till generally consisted of medium dense to dense silty sand with variable gravel content. Borings B-1/MW-1 and B-9/MW-9 encountered sandy interbeds within the weathered glacial till at depths of about 4 to 10 feet below grade. Glacial Till Deposits: Soils interpreted as unweathered glacial till were encountered in all of the explorations and were somewhat variable with respect to fines (silt and clay size material) content. In general, the unweathered glacial till consisted of dense to very dense silty sand with some gravel to sand with silt and gravel. This variation in fines content within the unweathered glacial till deposits is depicted in Generalized Cross Section A — A ; Figure 3. Glacial Advance Outwash Deposits: Soils interpreted as glacial advance outwash generally consisted dense to very dense sand with trace to some silt and gravel. Moderate heave was encountered within the glacial advance outwash deposits in some of the borings. Groundwater Conditions Groundwater was observed in all nine borings and in two of the test pits at the time of exploration. The observed groundwater conditions are interpreted to represent near surface perched groundwater and a deeper groundwater surface. Perched Groundwater: Slight perched groundwater seepage was encountered in boring B-1/MW- 1 at a depth of about 3 feet and in test pits TP-1A and TP1B at a depth of about 4 feet below grade. In boring B-1/MW-1, the groundwater was perched within existing fill soils above lower permeability weathered glacial till deposits. In test pits TP-1A and TP1B, the groundwater was perched in a sand seam in glacial till deposits. Groundwater: Groundwater seepage was encountered in all nine borings at the time of drilling and in subsequent groundwater monitoring well readings, which are presented in the following section. Groundwater depth readings ranged from about 13 to 18 feet below existing grade, or from about elevation 26'/2 feet to 23'/z feet at the time this report was prepared. In general, groundwater seepage encountered in the borings was rapid once the borings encountered the glacial advance outwash sand deposits at depths of about 24 to 30 feet below grade. At some of the explorations heave was encountered within the glacial advance outwash deposit. Groundwater seepage rates above the glacial advance outwash within the glacial till deposits ranges from very slight to moderate and appear to correspond to the variable fines content (percentage of silt and clay) of the glacial till encountered on site, with slower seepage rates encountered in till soils with higher fines content. Groundwater Monitoring Well Readings: Groundwater monitoring wells were installed in all 9 borings to evaluate fluctuations in groundwater conditions. Monitoring well construction details Page 5 ZipperGeo Geoprofessional Consultants Mar-Vel Marble Redevelopment Project No. 1798.01 November 21, 2017 are presented on the boring logs enclosed in Appendix A. Groundwater monitoring well readings are presented in the following table. SUMMARY OF GROUNDWATER MONITORING WELL READINGS Exploration Approximate Ground Surface Elevation(ft) Date Measured Approximate groundwater Depth (ft) Approximate Groundwater Elevation (ft) B-1 /MW-1 40.88 5/22/2017 14.63 26.25 5/26/2017 14.37 26.51 6/7/2017 14.85 26.03 B-2/MW-2 39.51 5/22/2017 13.18 26.33 5/26/2017 13.88 26.63 6/7/2017 13.20 26.31 10/2/2017 15.56 23.95 B-3/MW-3 41.00 9/14/2017 17.01 23.99 10/2/2017 17.31 23.69 B-4/MW-4 41.32 9/14/2017 17.32 24.00 10/2/2017 17.64 23.68 B-5/MW-5 41.20 9/14/2017 16.50 24.70 10/2/2017 16.86 24.34 B-6/MW-6 39.17 9/14/2017 15.12 24.05 10/2/2017 15.44 23.73 B-7/MW-7 39.08 9/14/2017 14.47 24.61 10/2/2017 14.77 24.31 B-8/MW-8 42.62 9/14/2017 18.03 24.59 10/2/2017 18.42 24.20 B-9/MW-9 40.82 9/14/2017 15.02 25.80 10/2/2017 16.28 24.54 1. Ground surface elevations for borings B-1/MW-1 through B-9/MW-9 are based on groundwater monitoring well top of monument elevations provided by Pacific Coast Surveys, Inc. Groundwater levels, flow rates and soil moisture conditions should be expected to vary throughout the year. Fluctuations of the groundwater levels will likely occur due to seasonal variations in the amount of rainfall, runoff and other factors not evident at the time the explorations were performed. Therefore, groundwater levels during construction or at other times in the life of the structure may be higher than indicated on the logs. Groundwater level fluctuations and perched water should be considered when developing the design and construction plans for the project. Field Screening for VOCs Soil samples recovered from the explorations were screened in the field shortly after collection with a hand held Photoionization Detector (PID) to evaluate the presence or absence of Volatile Page 6 Z i ppe rG eo Mar-Vel Marble Redevelopment Gevprofessional Consultants Project No. 1798.01 November 21, 2017 Organic Compounds (VOCs). PID readings are presented on the exploration logs in Appendix A in parts per million (ppm). Geotechnical Laboratory Testing Geotechnical laboratory testing was completed on select soil samples obtained from the borings. Laboratory testing included moisture content and grain size analysis tests. Due to the suspect presence of petroleum contaminants in the upper portion of boring B-2, our geotechnical tests were primarily completed on samples collected in boring B-1. The results of the moisture content tests are shown on the boring logs. Results for the grain size analyses are provided in Appendix B. In borings B-1, the moisture content of the surficial fill encountered to a depth of about 3'/2 feet was about 13 percent. The moisture content of the underlying weathered and unweathered glacial till deposits encountered between 3'/z and 25 feet ranged from about 8 to 12 percent. Three grain size analysis tests were completed on samples collected from boring B-1 and considered representative of the weathered and unweathered glacial till deposits and the underlying glacial outwash deposits. The weathered and unweathered glacial till samples collected at depths of 7'/2 and 15 feet had fines contents (silt and clay size particles) of about 40 and 46 percent, respectively. The underlying glacial outwash sample collected at a depth of 30 feet had a fines content of about 5 percent. CONCLUSIONS AND RECOMMENDATIONS General Considerations Based on our subsurface exploration program and geotechnical evaluation, we conclude that the proposed project is feasible from a geotechnical standpoint, contingent on proper design and construction practices and implementation of the recommendations presented in this report. Based on our analyses, conventional spread footings and slab -on -grade concrete floors can be used for the new building. Geotechnical engineering recommendations for temporary cuts, temporary shoring, foundations, floor slabs, and other earthwork related phases of the project are outlined below. The recommendations contained in this report are based upon the results of field and laboratory testing (which are presented in Appendices A and B), engineering analyses, and our current understanding of the proposed project. ASTM and Washington State Department of Transportation (WSDOT) specification codes cited herein respectively refer to the current manual published by the American Society for Testing & Materials and the current edition of the Standard Specifications for Road, Bridge, and Municipal Construction, (M41-10). Page 7 ZipperGeo Gevprofessional Consultants Seismic Considerations Mar-Vel Marble Redevelopment Project No. 1798.01 November 21, 2017 The development was evaluated relative to seismic hazards resulting from ground shaking associated with the Risk -Targeted Maximum Considered Earthquake (MCER) Ground Motion Response Acceleration and the Maximum Considered Earthquake Geometric Mean (MCEG) Peak Ground Acceleration in accordance with the 2012/2015 International Building Code (IBC). The results of our seismic hazard analyses and recommended seismic design parameters are presented in the following sections. Ground Surface Rupture: We evaluated the potential for seismic ground surface rupture at the site by reviewing the USGS Quaternary Fault Web Mapping Application. The mapping application indicates that there are no mapped Quaternary faults within 5 miles of the site. It is our opinion that the risk of ground surface rupture at the site is low. Landsliding: Based on the relatively level topography of the site and surrounding vicinity, the risk of earthquake -induced landsliding is low. Soil Liquefaction and Lateral Spread: Liquefaction is a phenomenon wherein saturated cohesionless soils build up excess pore water pressures during earthquake loading. Liquefaction typically occurs in loose soils, but may occur in denser soils if the ground shaking is sufficiently strong. The explorations primarily encountered glacially consolidated glacial till over glacial outwash deposits. Based on the dense to very dense nature of these soils below the groundwater table, it is our opinion that the potential for liquefaction at the site is low. Lateral spreading is a phenomenon in which soil deposits which underlie a site can experience significant lateral displacements associated with the reduction in soil strength caused by soil liquefaction. This phenomenon tends to occur most commonly at sites where the soil deposits can flow toward a "free -face", such as a water body. Due to the lack of liquefiable soils at the site and the lack of a nearby "free -face" condition, it is our opinion that the risk of lateral spreading at the site is low. IBC Seismic Design Parameters: 2012/2015 IBC Seismic Design parameters are summarized on the table below. Code Used Site Classification 2012/2015 International Building Code (IBC)' C 2 Ss Spectral Acceleration for a Short Period 1.270g (Site Class B) S1 Spectral Acceleration for a 1-Second Period 0.498g (site Class B) Fa Site Coefficient for a Short Period 1.000 (Site Class C) Fv Site Coefficient for a 1-Second Period 1.302 (Site Class C) SMs Maximum considered spectral response acceleration for a Short Period 1.270g (Site Class C) Page 8 ZipperGeo Gevprofessional Consultants Mar-Vel Marble Redevelopment Project No. 1798.01 November 21, 2017 Code Used Site Classification Snm Maximum considered spectral response acceleration 0.648g (Site Class C) for a 1-Second Period Sos Five -percent damped design spectral response 0.847g (Site Class C) acceleration for a Short Period Sol Five -percent damped design spectral response 0.432g (Site Class C) acceleration for a 1-Second Period 1. In general accordance with the 201212015 International Building Code, Section 1613.3.2 and ASCE 7-10, Chapter 20. IBC Site Class is based on the average characteristics of the upper 100 feet of the subsurface profile. 2. The borings completed for this study extended to a maximum depth of 35 feet below grade. ZGA therefore determined the Site Class assuming that dense to hard glacially over -consolidated soils extend to 100 feet as suggested by published geologic maps for the project area. Site Preparation Existing Structure Removal: At the time this report was prepared, the three site buildings had been substantially demolished. However, portions of the foundations or other below grade structures may be present at currently undisclosed locations. We recommend that all existing foundation elements or other structures be demolished and removed from the proposed building area. Existing Utility Removal: We recommend that all underground utilities within the building pad be completely removed. Utility pipes outside the building envelope that are not used for the new development are expected to be located within the City of Edmonds right-of-way given the close proximity of the building envelope to property lines. Utility abandonment in the right-of-way should be completed in accordance with City of Edmonds requirements. Erosion Control Measures: Stripped surfaces and soil stockpiles are typically a source of runoff sediments. We recommend that silt fences, berms, straw waddles, and/or swales be installed around the downslope side of stripped areas and stockpiles in order to capture runoff water and sediment. If earthwork occurs during wet weather, we recommend that soil stockpiles be protected with anchored plastic sheeting. Temporary Drainage: Stripping, excavation, grading, and subgrade preparation should be performed in a manner and sequence that will provide drainage at all times and provide proper control of erosion. The near -surface site soils have a moderate to high fines (silt and clay) content and are therefore highly susceptible to disturbance and erosion when wet. The site should be graded to prevent water from ponding in construction areas and/or flowing into and/or over excavations. Exposed grades should be crowned, sloped, and smooth -drum rolled at the end of each day to facilitate drainage if inclement weather is forecasted. Accumulated water must be removed from subgrades and work areas immediately and prior to performing further work in the area. Equipment access may be limited and the amount of soil rendered unfit for use as structural fill may be greatly increased if drainage efforts are not accomplished in a timely manner. Successful drainage of saturated zones due to accumulations of surface water would be relatively Page 9 Z i ppe rG eo Mar-Vel Marble Redevelopment Gevprofessional Consultants Project No. 1798.01 November 21, 2017 slow due to the fines content of the surficial soils. Instead, aeration or removal and replacement would be more expeditious. Runoff from the existing paved areas around the site should not be allowed to flow into excavation areas. We recommend that asphalt berms or sandbags be used to divert runoff around the excavation areas to a suitable discharge location. Clearing and Stripping: We anticipate that clearing and stripping will be limited to the removal of a few existing ornamental plantings on the north side of the building, as well as any underlying organic -rich topsoil. We anticipate that stripping depths will vary from about 6 to 12 inches in planter areas. Subgrade Preparation: Once site preparation is complete, all areas that do not require over - excavation and are at design subgrade elevation or areas that will receive new structural fill should be compacted to a firm and unyielding condition. Some moisture conditioning of site soils may be required to achieve a moisture content appropriate for compaction. This is generally within ±2 percent of the soils optimum moisture content. In our opinion, earthwork should be completed during drier periods of the year when soil moisture content can be controlled by aeration and drying. If earthwork or construction activities take place during extended periods of wet weather, or if the in -situ moisture conditions are elevated above the optimum moisture content, the soils could become unstable or not be compactable. In the event the exposed subgrade becomes unstable, yielding, or unable to be compacted due to high moisture conditions, we recommend that the materials be removed to a sufficient depth in order to develop stable subgrade soils that can be compacted to the minimum recommended levels. The severity of construction problems will be dependent, in part, on the precautions that are taken by the contractor to protect the subgrade soils. Once compacted, subgrades should be evaluated by a geotechnical engineer through visual observation, density testing, and proof rolling if the building excavation is accessible with heavy rubber -tired construction equipment given site access to assess the subgrade adequacy and to detect soft and/or yielding soils. In the event that compaction fails to meet the specified criteria, the upper 12 inches of subgrade should be scarified and moisture conditioned as necessary to obtain at least 95 percent of the maximum laboratory density (per ASTM D1557). Those soils which are soft, yielding, or unable to be compacted to the specified criteria should be over - excavated and replaced with suitable material as recommended in the Structural Fill section of this report. Alternatively, over -optimum soils could be treated with cement as a method to stabilize and strengthen soft, wet soils. To protect stable subgrades, either inside or outside the building excavation, we recommend using crushed rock or crushed recycled concrete. The thickness of the protective layer should be determined at the time of construction and be based on the moisture condition of the soil and the amount of anticipated construction traffic. Page 10 Z i ppe rG eo Mar-Vel Marble Redevelopment Gevprofessional Consultants Project No. 1798.01 November 21, 2017 Freezing Conditions: If earthwork takes place during freezing conditions, all exposed subgrades should be allowed to thaw and then be compacted prior to placing subsequent lifts of structural fill. Alternatively, the frozen material could be stripped from the subgrade to expose unfrozen soil prior to placing subsequent lifts of fill or foundation components. The frozen soil should not be reused as structural fill until it is allowed to thaw and adjusted to the proper moisture content, which may not be possible during winter months. Structural Fill Materials and Placement Structural fill includes any material placed below foundations and pavement sections, within utility trenches, and behind retaining walls. Prior to the placement of structural fill, all surfaces to receive fill should be prepared as previously recommended in the Site Preparation section of this report. Laboratory Testing: Representative samples of on -site and imported soils to be used as structural fill should be submitted for laboratory testing at least 4 days in advance of its intended use in order to complete the necessary Proctor tests. Re -Use of Site Soils as Structural Fill: It is our opinion that the site glacial till soils typically consisting of silty sand with variable gravel content are suitable for reuse as general structural fill from a compositional standpoint provided it is placed and compacted in accordance with the recommendations presented in this report. The reuse of site soils as structural fill during wet weather will be much more difficult. We recommend that site soils used as structural fill have less than 4 percent organics by weight and have no woody debris greater than '/2 inch in diameter. We recommend that all pieces of organic material greater than inch in diameter be picked out of the fill before it is compacted. Any organic -rich soil and high plasticity clay derived from earthwork activities should be utilized in landscape areas or wasted from the site. Imported Structural Fill: Imported structural fill may be required due to weather or other reasons. The appropriate type of imported structural fill will depend on weather conditions. During extended periods of dry weather, we recommend imported fill meet the requirements of Common Borrow as specified in Section 9-03.14(3) of the 2016 Washington State Department of Transportation, Standard Specifications for Road, Bridge, and Municipal Construction (WSDOT Standard Specifications). During wet weather, higher -quality structural fill might be required, as Common Borrow may contain sufficient fines to be moisture sensitive. During wet weather we recommend that imported structural fill meet the requirements of Gravel Borrow as specified in Section 9-03.14(1) of the WSDOT Standard Specifications. Retaining Wall Backfill: With the exception of permanent foundation walls constructed directly in front of soldier pile retaining walls, any site retaining walls should include a drainage fill zone extending at least two feet back from the back face of wall for the entire wall height. The drainage fill should meet the requirements of Gravel Backfill for Walls as specified in Section 9-03.12(2) of the WSDOT Standard Specifications. Page 11 Z i ppe rG eo Mar-Vel Marble Redevelopment Gevprofessivnal Consultants Project No. 1798.01 November 21, 2017 Pavement Subgrades: Any structural fill used within the upper 2 feet below pavement sections should have a minimum California Bearing Ratio (CBR) of 15 when compacted to a minimum of 95 percent of the modified Proctor maximum dry density. A CBR value of 15 is representative of the existing soils encountered when compacted as recommended in this report. Moisture Content: The suitability of soil for use as structural fill will depend on the time of year, the moisture content of the soil, and the fines content (that portion passing the U.S. No. 200 sieve) of the soil. As the amount of fines increases, the soil becomes increasingly sensitive to small changes in moisture content. Soils containing more than about 5 percent fines (such as most of the on -site soils) cannot be consistently compacted to the appropriate levels when the moisture content is more than approximately 2 percent above or below the optimum moisture content (per ASTM D1557). Optimum moisture content is that moisture content which results in the greatest compacted dry density with a specified compactive effort. Fill Placement: Structural fill should be placed in horizontal lifts not exceeding 10 inches in loose thickness. Each lift of fill should be compacted using compaction equipment suitable for the soil type and lift thickness. Each lift of fill should be compacted to the minimum levels recommended below based on the maximum laboratory dry density as determined by the ASTM D1557 Modified Proctor Compaction Test. Moisture content of fill at the time of placement should be within plus or minus 2 percent of optimum moisture content for compaction as determined by the ASTM D1557 test method. Compaction Criteria: Our recommendations for soil compaction are summarized in the following table. Structural fill for roadways and utility trenches in municipal rights -of -way should be placed and compacted in accordance with City of Edmonds codes and standards. We recommend that a geotechnical engineer be present during grading so that an adequate number of density tests may be conducted as structural fill placement occurs. In this way, the adequacy of the earthwork may be evaluated as it proceeds. RECOMMENDED SOIL COMPACTION LEVELS Location Minimum Percent Compaction* All fill below building floor slabs and foundations 95 Upper 2 feet of fill below floor slabs and pavements 95 Pavement fill below two feet 92 Retaining wall backfill less than 3 feet from wall 90 Retaining wall backfill more than 3 feet from wall 92 Upper two feet of utility trench backfill 95 Utility trenches below two feet 92 Landscape Areas 90 * ASTM D 1557 Modified Proctor Maximum Dry Density Page 12 ZipperGeo Gevprofessional Consultants Utility Trenching and Backfilling Mar-Vel Marble Redevelopment Project No. 1798.01 November 21, 2017 We recommend that utility trenching conform to all applicable federal, state, and local regulations, such as OSHA and WISHA, for open excavations. Trench excavation safety guidelines are presented in WAC Chapter 296-155 and WISHA RCW Chapter 49.17. Dewatering: Some excavations for utilities and underground structures may encounter zones of perched groundwater or the water table. At the time of our evaluation, slight perched groundwater seepage was encountered in boring B-1/MW-1 at a depth of about 3 feet and in test pits TP-1A and TP1 B at a depth of about 4 feet below grade. Groundwater seepage was encountered below the perched zones in all nine borings at the time of drilling and in subsequent groundwater monitoring well readings. Groundwater depth readings ranged from about 13 to 18 feet below existing grade, or from about elevation 26'/2 feet to 23'/2 feet at the time this report was prepared. Groundwater seepage rates were generally slight to moderate on those portions of the glacial till located below the water table, and rapid within the underlying glacial advance outwash deposits. The amount of seepage that may be encountered in site excavations will likely be a function of the time of year, the size of the excavation, the excavation depth, and how long the excavation remains open. The type and extent of dewatering measures needed, if any, will be a function of the groundwater conditions at the time of construction. Temporary systems could include pumped sumps, wellpoints or pumped wells. If seepage is encountered, flattening excavation sidewalls may be necessary to reduce the risk of caving. Otherwise, some caving of utility trench sidewalls should be anticipated where groundwater seepage is encountered. If dewatering becomes necessary, the appropriate type of dewatering system and means of disposing the water should be determined by the contractor based on the conditions encountered. Utility Subgrade Preparation: We recommend that all utility subgrades be firm and unyielding and free of all soils that are loose, disturbed, or pumping. Such soils should be removed and replaced, if necessary. All structural fill used to replace over -excavated soils should be compacted as recommended in the Structural Fill section of this report. If utility foundation soils are soft, we recommend that they be over -excavated 12 inches and replaced with crushed rock. Structures such as manholes and catch basins which extend into soft soils should be underlain by at least 12 inches of crushed gravel fill compacted to at least 90 percent of the modified Proctor maximum dry density. This granular material could consist of crushed rock, quarry spalls, or coarse crushed concrete. Alternatively, quarry spalls or pea gravel could be used until above the water level. It may be necessary to place a geotextile fabric over the native subgrade soils if they are too soft, to provide a separation between the bedding and subgrade soils. Bedding: We recommend that a minimum of 4 inches of bedding material be placed above and below all utilities or in general accordance with the utility manufacturer's recommendations and local ordinances. We recommend that pipe bedding consist of Gravel Backfill for Pipe Zone Page 13 Z i ppe rG eo Mar-Vel Marble Redevelopment Gevprofessivnal Consultants Project No. 1798.01 November 21, 2017 Bedding as specified in Section 9-03.12(3) of the WSDOT Standard Specifications. All trenches should be wide enough to allow for compaction around the haunches of the pipe, or material such as pea gravel should be used below the spring line of the pipes to eliminate the need for mechanical compaction in this portion of the trenches. If water is encountered in the excavations, it should be removed prior to fill placement. Trench Backfill: Materials, placement and compaction of utility trench backfill should be in accordance with the recommendations presented in the Structural Fill section of this report. In our opinion, the initial lift thickness should not exceed one foot unless recommended by the manufacturer to protect utilities from damage by compacting equipment. Light, hand operated compaction equipment may be utilized directly above utilities if damage resulting from heavier compaction equipment is of concern. Temporary and Permanent Slopes We anticipate that temporary open cuts may be utilized in conjunction with shoring during the construction of foundation elements for the proposed structure. Temporary excavation slope stability is a function of many factors, including: • The presence and abundance of groundwater; • The type and density of the various soil strata; • The depth of cut; • Surcharge loadings adjacent to the excavation; and • The length of time the excavation remains open. As the cut is deepened, or as the length of time an excavation is open increases, the likelihood of sidewall sloughing or failure increases; therefore, maintenance of safe slopes and worker safety should remain the responsibility of the contractor, who is present at the site, able to observe changes in the soil conditions, and monitor the performance of the excavation. It is exceedingly difficult under the variable circumstances to pre -establish a safe and "maintenance -free" temporary cut slope angle. Therefore, it should be the responsibility of the contractor to maintain safe temporary slope configurations since the contractor is continuously at the job site, able to observe the nature and condition of the cut slopes, and able to monitor the subsurface materials and groundwater conditions encountered. Unsupported vertical slopes or cuts deeper than 4 feet are not recommended if worker access is necessary. The cuts should be adequately sloped, shored, or supported to prevent injury to personnel from local sloughing and spalling. Temporary slope angles should conform to applicable Federal, State, and Local regulations based on the subsurface conditions observed at the time of construction. Based on the conditions observed in the borings and test pits, the weathered glacial till soils encountered in the upper 4 to 10 feet of the explorations appear to be representative of Type B soils, as described in Chapter 296-155, Part N, Excavation Trenching and Shoring, of the Page 14 Z i ppe rG eo Mar-Vel Marble Redevelopment Gevprofessivnal Consultants Project No. 1798.01 November 21, 2017 Washington Administrative Code (WAC). According to the Code, excavations less than 20 feet deep in Type B soils may be cut at a maximum temporary slope angle of 45 degrees (1 H:1 V). The underlying unweathered glacial till soils encountered in the explorations appear to be representative of Type A soils, as described in Chapter 296-155, Part N, Excavation Trenching and Shoring, of the Washington Administrative Code (WAC). According to the Code, excavations less than 20 feet deep in Type A soils may be cut at a maximum temporary slope angle of 53 degrees (3/4H:1V). Therefore, for preliminary planning purposes we recommend maximum temporary slope angles of 45 degrees (1H:1V) and 53 degrees (3/4HIV) for weathered and unweathered glacial till soils, respectively. According to Chapter 296-155 of the WAC, the contractor should make a determination of excavation side slopes based on classification of soils and site conditions encountered at the time of excavation. Temporary cuts may need to be constructed at flatter angles based upon the soil moisture and groundwater conditions at the time of construction and the location of soil stockpiles construction equipment, or other surcharge loads. Adjustments to the slope angles should be determined by the contractor at that time. We recommend that all permanent cut or fill slopes constructed in native soils be designed at a 2'/2H:1 V (Horizontal:Vertical) inclination or flatter. All permanent cut and fill slopes should be adequately protected from erosion both temporarily and permanently. Temporary Soldier Pile Shoring We understand that the new development will have roughly the same footprint as the existing structures (about a 1-foot lot -line setback with a few portions of the building set back about 3 to 4 feet). Preliminary plans indicate that the below grade parking level will have finished floor elevations ranging from about 32.7 to 31 feet. These parking level finished floor elevations are about 5 to 11 feet below existing exterior grades and we anticipate that excavations for foundation elements may extend about 1'/2 to 2 feet deeper for anticipated construction excavation depths of 7 to 13 feet. The eastern 25 feet of the building includes a below grade utility room with a finished floor elevation of 37 feet and a 5-foot diameter stormwater detention pipe with an invert elevation of about 30 feet. The utility room finished floor elevations is about 5 to 7 feet below existing exterior grades and we anticipate that excavations for foundation elements may extend about 1'/2 to 2 feet deeper for anticipated construction excavation depths of 7 to 9 feet with deeper excavations for the stormwater detention pipe. Based on the preliminary plans, we anticipate that temporary shoring will be needed along the perimeter of the site. Temporary construction easements for excavations and or shoring within the City of Edmonds right-of-way may also be needed depending on the layout and design of the shoring system. Temporary Soldier Pile Shoring Considerations: Soldier pile walls consist of vertical steel beams installed in drilled shafts that extend below the bottom of the cut. The shafts are typically backfilled below the bottom of the cut with structural or lean -mix concrete and controlled density fill (CDF) above the bottom of the cut. Once the cementitious material has hardened, the excavation Page 15 Z i ppe rG eo Mar-Vel Marble Redevelopment Gevprofessivnal Consultants Project No. 1798.01 November 21, 2017 proceeds and lagging (typically dimensional lumber for temporary applications) is installed between the flanges of the vertical elements to support the cut as the excavation extends down. Soldier pile and lagging walls that are not exposed to significant surcharge loads can typically cantilever to a maximum exposed height of about 15 feet. Beyond these heights, or if surcharge loads are sufficient, tie back anchors are typically required to provide additional lateral support. The length of tie backs is typically on the order of 25 to 50 feet, depending on the required anchor capacities. Provided the maximum exposed height of temporary shoring on this project is about 15 feet or less, we expect cantilever -type soldier pile shoring will be feasible for this project. Rapid groundwater seepage rates were observed within the glacial advance outwash deposits encountered about 24 to 30 feet below existing grade, and heave was noted within this unit in some of the borings. To reduce the potential for soldier pile wall shaft instability during construction, we recommend that the design soldier pile shaft excavation depth be maintained at least 3 feet above the glacial advance outwash deposits, if feasible. During our evaluation for this project, ZGA representatives monitored the excavation of two soldier pile drilled shafts completed on the property to the east of the subject site and interviewed the foreman for the shoring contractor, Pile Contractors, Inc. At that site, significant water intrusion into the shaft excavations typically occurred at depths of about 20 to 22 feet. The contractor indicated that they could maintain borehole stability using a synthetic drilling fluid additive without the need for temporary casing, and placed shaft concrete using tremie methods. We recommend that the contractor for this project be prepared to case shafts or use other means to stabilize shaft excavation, as needed. We further recommend that the shoring contractor's bid include a line item for borehole stabilization and that the project schedule include provisions for stabilization measures, if needed. Please refer to the Utility Trench and Backfilling section of this report for a discussion regarding construction dewatering. The shoring design criteria presented in this report should be used by the shoring designer to design an appropriate shoring system. The shoring design should be reviewed by Zipper Geo Associates for conformance with design criteria presented herein. It is generally not the purpose of this report to provide specific criteria for construction methods, materials or procedures for shoring. It should be the responsibility of the shoring designer and contractor to verify the subsurface conditions prior to bidding and determine select appropriate materials and methods for design and construction. Soldier Pile Shoring and Lagging Design Parameters: The design of shoring is generally accomplished using empirical relationships and apparent earth pressure distributions. These earth pressure distributions or envelopes do not represent the precise distribution of earth pressures but rather constitute hypothetical pressures from which tieback loads can be calculated which would not likely be exceeded in the excavation. Additionally, pressures must be selected to limit deflections, both vertical and horizontal, of nearby settlement sensitive structures, roadways and utilities. The design of soldier pile and lagging shoring should include lateral pressures exerted by the adjacent soil, surcharge loads from the adjacent building, and other surcharges such as traffic, construction materials, crane pad loads, or temporary soil stockpiles Page 16 Z i ppe rG eo Mar-Vel Marble Redevelopment Gevprofessional Consultants Project No. 1798.01 November 21, 2017 adjacent to the excavation. Lateral load resistance can be mobilized passive pressures on members that extend below the bottom of the excavation. Increased lateral load resistance could be mobilized through the use of tiebacks that extend beyond the pressure envelopes, if needed. Design of soldier pile shoring should be based on either "active" or "at -rest' lateral earth pressures, depending on the degree of deformation that the shoring wall can tolerate. Lateral wall movement for soldier pile shoring designed using active earth pressures typically range from about 0.2 percent to 0.5 percent of the wall height. The lateral movement is typically accompanied by vertical settlement of about 0.15 percent to 0.5 percent of the wall height with the maximum occurring immediately behind the wall face and trending to zero at a distance of roughly two times the wall height. If existing utilities or buildings within the zone of influence are considered to be insensitive to this degree of settlement, then it would be appropriate to design utilizing active earth pressures. An assumed "at -rest' earth pressure condition theoretically assumes no movement of the soil behind the shoring, however, some settlement should realistically be anticipated due to construction practices and/or the fact that it is not possible to construct a perfectly stiff shoring system. The attached Temporary Soldier Pile Shoring Design Parameters, Figure 4 provides our recommendations for cantilever soldier pile shoring design. Additionally, construction loads such a stockpiled soils and crane outrigger loads must be applied. Figure 5 provides pressure diagrams for lateral earth pressures resulting from vertical surcharges behind shoring walls. For traffic surcharges on the shoring walls we recommend using an equivalent soil surcharge of 2 feet (250 psf) be added to the walls extending down to an elevation based on a 1 H:1 V influence line from the drive surface to the shoring. Construction of soldier pile shoring walls should be in accordance with Section 6-16 of the WSDOT Standard Specifications. When caving soil conditions are encountered in soldier pile excavations, we recommend the contractor case or otherwise stabilize the excavation in general accordance with WSDOT Standard Specification Section 6-16.3(3), Shaft Excavation. We anticipate that the saturated glacial advance outwash deposits encountered at depths of about 24 to 30 feet below grade in our explorations will be highly susceptible to caving. We also recommend that shaft backfilling be completed in general accordance with WSDOT Standard Specification Section 6-16.3(5), Backfilling Shaft, particularly with respect to when water is present in the excavations. We recommend the contractor be prepared to clean out the bottom of all shafts using a clean -out bucket so that slough is limited to 2 inches or less. Shoring Monitoring Plan: Any time an excavation is made below the level of existing buildings, utilities or other structures, there is risk of damage even if a well -designed shoring system has been planned. If there are settlement -sensitive structures or facilities located within a horizontal distance of two times the wall height, we recommend a shoring monitoring program be implemented. Page 17 Z i ppe rG eo Mar-Vel Marble Redevelopment Gevprofessional Consultants Project No. 1798.01 November 21, 2017 In order to establish the condition of existing facilities prior to construction, we recommend that the owner and/or representatives make a complete inspection and evaluation of pavements, structures, and utilities around the proposed excavation. This inspection should be directed towards detecting any existing signs of damage, particularly those caused by settlement or lateral movement. The observations should be documented by pictures, notes, survey drawings, or other means of verification. The contractors also should establish for their own records the existing conditions prior to construction. The monitoring program should include measurements of the horizontal and vertical movements of the adjacent structures and the shoring system itself. At least two reference lines should be established adjacent to the excavation at horizontal distances back from the excavation space of about 1/4H and 3/4H, where H is the final excavation height. Reference points for horizontal movement should also be placed at the tops of the soldier piles. The measuring system used for shoring monitoring should have an accuracy of at least 0.01-foot. All reference points on the existing structures should be installed and readings taken prior to commencing the excavation. All reference points should be read prior to and during critical stages of construction when the piles are not braced by the structure. The frequency of readings will depend on the results of previous readings and the rate of construction. As a minimum, readings should be taken at least once a week throughout construction until the permanent basement walls are completed up to the ground level of the building. All readings should be reviewed by the geotechnical and structural engineers. Shallow Foundations Based on our analyses, conventional spread footings will provide adequate support for the proposed building provided that the foundation subgrades are properly prepared. Foundation support for the building may be obtained from either the native glacial till deposits or from new structural fill placed in accordance with the recommendations provided in this report. The upper one foot of foundation subgrades should be moisture conditioned, as necessary, and compacted to a firm and non -yielding condition and to at least 95 percent of the modified Proctor maximum dry density per ASTM D 1557. Borings B-1/MW-1, B-2/MW-2. B-8/MW-8, and test pits TP-2A and B encountered up to about 5'/2 feet of existing fill. We do not recommend supporting foundations on existing fill soils. If unsatisfactory fills are encountered within the proposed building area, such fills should be removed and the excavation thoroughly cleaned prior to backfill placement and/or construction. For all footings, we recommend that any over -excavation of unsuitable fill soils extend outside the limits of the footings a distance equal to the depth of over -excavation, with the exception of footings constructed against shoring walls in which case the over excavation along the face of the shoring wall may be vertical. Foundation design recommendations are presented in the following sections. Page 18 Z i ppe rG eo Mar-Vel Marble Redevelopment Gevprofessivnal Consultants Project No. 1798.01 November 21, 2017 Allowable Bearing Pressure: Continuous and isolated column footings bearing on subgrades prepared as recommended above may be designed for a maximum allowable, net, bearing pressure of 3,000 psf if supported on compacted structural fill or native medium dense silty sand deposits, and 4,500 psf if supported on dense to very dense, undisturbed, silty sand deposits. A one-third increase of the bearing pressure may be used for short -tern dynamic loads such as wind and seismic forces. Shallow Foundation Depth and Width: For frost protection, the bottom of all exterior footings should bear at least 18 inches below the lowest adjacent outside grade, whereas the bottoms of interior footings should bear at least 12 inches below the surrounding slab surface level. We recommend that all continuous wall and isolated column footings be at least 12 and 24 inches wide, respectively. Lateral Resistance: We recommend using allowable base friction and passive earth values of 0.35 and 325 pcf equivalent fluid pressure, respectively. We recommend that passive resistance be neglected in the upper 18 inches of embedment. Estimated Settlement: Assuming the foundation subgrade soils are prepared in accordance with recommendations presented herein, we estimate that total and differential settlements will be less than one inch and'/z inch, respectively, over a distance of 40 feet. Permanent Retaining Walls We expect the project to include some backfilled cast -in -place concrete retaining walls. For recommended bearing capacities and lateral resistance parameters, refer to the Shallow Foundations section above. Additional recommendations for these structures are provided below. Lateral Earth Pressures: The lateral soil pressures acting on backfilled retaining walls will depend on the nature and density of the soil behind the wall, and the ability of the wall to yield in response to the earth loads. Yielding walls (i.e. walls that are free to translate or rotate) that are able to displace laterally at least 0.001 H, where H is the height of the wall, may be designed for active earth pressures. Non -yielding walls (i.e. walls that are not free to translate or rotate) should be designed for at -rest earth pressures. Non -yielding walls include walls that are braced to another wall or structure, and wall corners. Assuming that walls are backfilled and drained as described in the following paragraphs, we recommend that yielding walls supporting horizontal backfill be designed using an equivalent fluid density of 34 pcf (active earth pressure). Non -yielding walls should be designed using an equivalent fluid density of 55 pcf (at -rest earth pressure). Design of permanent retaining walls should consider additional earth pressure resulting from the design seismic event. For the seismic case, walls should be designed for an additional uniform, total seismic earth pressure distribution of 11 H. Page 19 Z i ppe rG eo Mar-Vel Marble Redevelopment Gevprofessivnal Consultants Project No. 1798.01 November 21, 2017 The above -recommended lateral earth pressures do not include the effects of sloping backfill surfaces, surcharges such as traffic loads, other surface loading, or hydrostatic pressures. Traffic surcharge loads on the basement walls can be evaluated considering an equivalent soil surcharge of 2 feet (250 psf) added to the walls extending down to an elevation based on a 1 H:1 V influence line from the drive surface to the wall, similar to the methodology recommended for the shoring walls. If other surcharge conditions exist, we should be consulted to provide revised earth pressure recommendations. Slab -on -Grade Floors Based on preliminary plans, it appears that the utility room located in the eastern portion of the building will include a conventional concrete slab -on -grade floor, while the below grade parking area in the central and western portions of the building will include concrete pavements intended to support passenger vehicle traffic. Recommendations for building slab -on -grade concrete floors and parking garage concrete pavements are presented below. Subgrade Conditions and Preparation: The native glacial till soils appear to be suitable for support of the slabs provided they can be compacted to the minimum recommended levels. Where unsuitable soil is present, such as loose soils or undocumented fill, we recommend that the material be over -excavated and replaced with common borrow or select borrow, depending on the prevailing weather conditions. Subgrades should be prepared in accordance with the recommendations presented in the Subgrade Preparation section of this report. Slab Base: To provide a uniform slab bearing surface, we recommend the on -grade slabs in non - parking areas be underlain by a 4-inch thick layer of compacted crushed rock meet the requirements of Crushed Surfacing Top Course as specified in Section 9-03.9(3) of the WSDOT Standard Specifications. Within the parking garage, we recommend that the top course thickness be increased to 6 inches. Vapor Retarder: From a geotechnical standpoint, a vapor barrier is not considered to be necessary for the proposed building. Where potential slab moisture is a concern or where moisture sensitive floor coverings are planned, we recommend that a 10- to 15-mil moisture barrier be installed beneath all interior slabs. We recommend using a puncture -resistant product such as Stego Wrap or an approved equivalent that is classified as a Class A vapor retarder in accordance with ASTM E1745. Puncturing the vapor barrier should be avoided; construction traffic should not be allowed to drive over any vapor barrier material. The slab designer should and contractor should refer to ACI 302 for procedures and cautions regarding the use and placement of a vapor retarder. We recommend that installation of the vapor barrier be completed in accordance with the manufacturers recommendations. ZGA is completing Phase II environmental services to evaluate the approximate extent and concentration of contaminants that may be present on site. If soil or groundwater containing Page 20 Z i ppe rG eo Mar-Vel Marble Redevelopment Gevprofessional Consultants Project No. 1798.01 November 21, 2017 volatile organic compounds (VOCs) are encountered below planned excavation depths a more extensive vapor retarder system than recommended above may be warranted and recommended in our Phase II report to reduce the potential for vapor intrusion into the building. Subgrade Modulus: For design of on -grade concrete slabs supported on dense to very dense native soils, we recommend a vertical modulus of subgrade reaction of 250 pounds per cubic inch (pci) be used. For slabs supported on compacted structural fill or medium dense native soil, we recommend using a vertical modulus of subgrade reaction of 200 pounds per cubic inch. Parking Garage Concrete Pavement: The following parking level concrete pavement design recommendations are based on an assumed modulus of rupture of 600 psi and a minimum compressive strength of 4,000 psi for the concrete. For light duty pavement, we recommend a minimum of 5 inches of concrete over 6 inches of crushed aggregate base. Based on the soils encountered, we recommend that concrete pavements be lightly reinforced to control cracking and have relatively closely spaced control joints on the order of 10 to 12 feet. We recommend that minimum reinforcement consist of 6x6-W2.OxW2.0 welded wire fabric, or equivalent. Drainage Considerations Surface Drainage: Final site grades should be sloped to carry surface water away from buildings and other drainage -sensitive areas. Additionally, site grades should be designed such that concentrated runoff on softscape surfaces is avoided. Sub -slab Drainage: Due to the low permeability of the glacial till soils beneath the garage slab, and observed groundwater conditions, we recommend that sub -slab drains be installed below the parking level concrete slab -on -grade floor. We recommend using 4-inch diameter perforated PVC pipes embedded at least 2 feet below the bottom of the slab that are spaced on 15- to 20-foot centers. We recommend that the trenches be backfilled with aggregate meeting the gradation requirements of WSDOT Standard specification 9-03.12(4), Gravel Backfill for Drains and that the trenches be lined with a non -woven filter fabric such as Mirafi 140N or equivalent prior to placing the drainpipe and drainage aggregate. We recommend the pipes have a minimum slope of 6 inches in 50 feet. The pipes should be laid out such that they do not interfere with the bearing soils of adjacent foundations. Bearing soils within an envelope defined by extending horizontally one foot from all sides of a foundations and then down at a 1 H:1V slope should not be disturbed. Subsurface Perimeter Drainage: We recommend a permanent subsurface drainage system be installed around the perimeter of the structure. We anticipate two types of systems may be required; a system for backfilled retaining walls and a system for walls cast against temporary shoring walls. Our recommendations for each are provided below. Backfilled Walls: Drains for backfilled walls should consist of an aggregate drainage zone (as recommended in the Structural Fill section) and a drain pipe. The footing drains should consist of a minimum 4-inch diameter, Schedule 40, rigid, perforated PVC pipe placed at Page 21 ZipperGeo Gevprofessional Consultants Mar-Vel Marble Redevelopment Project No. 1798.01 November 21, 2017 the base of the heel of the footing with the perforations facing down. The pipe should be surrounded by a minimum of 6 inches of clean free -draining granular material conforming to WSDOT Standard Specification 9-03.12(4), Gravel Backfill for Drains. A non -woven filter fabric such as Mirafi 140N, or equivalent, should envelope the free -draining granular material. At appropriate intervals such that water backup does not occur, the drainpipe should be connected to a tightline system leading to a suitable discharge. Cleanouts should be provided for future maintenance. The tightline system must be separate from the roof drain system. • Walls Cast Against Shoring Walls: Prefabricated drainage matting (such as Miradrain or J-Drain 400) should be placed on the outside face of shoring (lagging) full width and height of the wall between soldier pile flanges. Near the bottom of the wall, and at the center between soldier piles, a prefabricated connector (such as Drain Grate) should be connected to the drainage matting. The connector should be fitted with a 3-inch minimum diameter weep hole pipe that will extend through the face of the permanent foundation wall. The weep hole pipe should be connected to a tightline system leading to a suitable discharge. CLOSURE The analysis and recommendations presented in this report are based, in part, on the explorations completed for this study. The number, location, and depth of the explorations were completed within the constraints of budget and site access so as to yield the information to formulate our recommendations. Project plans were in the preliminary stage at the time this report was prepared. We therefore recommend we be provided an opportunity to review the final plans and specifications when they become available in order to assess that the recommendations and design considerations presented in this report have been properly interpreted and implemented into the project design. The performance of earthwork, structural fill, shoring, foundations, and pavements depend greatly on proper site preparation and construction procedures. We recommend that Zipper Geo Associates, LLC be retained to provide geotechnical engineering services during the earthwork - related construction phases of the project. If variations in subsurface conditions are observed at that time, a qualified geotechnical engineer could provide additional geotechnical recommendations to the contractor and design team in a timely manner as the project construction progresses. This report has been prepared for the exclusive use of Mary Olsen, and her agents, for specific application to this project and has been prepared in accordance with generally accepted geotechnical engineering practices. No warranties, express or implied, are intended or made. Site safety, excavation support, and dewatering requirements are the responsibility of others. In the event that changes in the nature, design, or location of the project as outlined in this report are planned, the conclusions and recommendations contained in this report shall not be considered valid unless Zipper Geo Associates, LLC reviews the changes and either verifies or modifies the conclusions of this report in writing. Page 22 REFERENCE: GOOGLE EARTH 2O17 VICINITY MAP NOT TO SCALE SITE AND EXPLORATION PLAN LEGEND: FIGURE 2 9 B-1/MW-1 BORING/GROUNDWATER MONITORING WELL NUMBER AND APPROXIMATE LOCATION TP-1A TEST PIT NUMBER AND APPROXIMATE LOCATION A A' GENERALIZED SUBSURFACE PROFILE APPROXIMATE LOCATION AND DESIGNATION GENERALIZED CROSS SECTION LEGEND: FIGURE 3 B-1/MW-1 EXPLORATION NUMBER (OFFSET 15' W) BORING OFFSET DISTANCE & DIRECTION FROM SECTION LINE Wo GROUND WATER LEVEL WHILE DRILLING OR DATE NOTED GROUNDWATER MONITORING WELL SAND PACK 32 STANDARD PENETRATION TEST (SPT) BLOWCOUNT ? ? APPROXIMATE SOIL UNIT BOUNDARY (INTERPOLATED BETWEEN EXPLORATIONS) TD=35.5 TOTAL DEPTH OF EXPLORATION IN FEET GENERAL NOTES FOR FIGURES 2 AND 3 THE TOPOGRAPHIC AND BUILDING LAYOUT BASE MAPS PRESENTED ON FIGURE 2 ARE TAKEN FROM THE PRELIMINARY GRADING AND UTILITY PLAN, SHEET C3.1, PREPARED BY GC ENGINEERING, DATED OCTOBER 6, 2016. 2. THE LOCATION AND ELEVATION OF THE BORINGS SHOWN ON FIGURES 2 AND 3 WERE PROVIDED BY PACIFIC COAST SURVEYS, INC. THE LOCATION AND ELEVATION OF THE TEST PITS ARE BASED ON FIELD MEASUREMENTS TAKEN WITH A FIBERGLASS TAPE MEASURE RELATIVE TO EXISTING SITE FEATURES VISIBLE ON THE ABOVE REFERENCED BASE MAP, AND SHOULD BE CONSIDERED ACCURATE ONLY TO THE DEGREE IMPLIED BY THE MEASUREMENT METHODS. 3. THE SUBSURFACE CONDITIONS SHOWN ON THE GENERALIZED CROSS SECTION ARE BASED UPON INTERPOLATION BETWEEN EXPLORATIONS AND MAY NOT REPRESENT ACTUAL SUBSURFACE CONDITIONS. SIMPLIFIED NAMES ARE SHOWN FOR SOIL DEPOSITS, BASED ON GENERALIZATIONS OF SOIL DESCRIPTIONS. SEE EXPLORATION LOGS AND REPORT TEXT FOR MORE DETAILED SOIL AND GROUNDWATER DESCRIPTIONS. Ex1ST FIRE DF�A HYNT 11PBRACIE ENISTI its RAMP ! PER CITY 11W REMENTS i W,?TRIINCATE1) DOMES �4 _ -MIST s �L+14'ER POLE .' i. 3 EUSE WATEA' rff I'i s4 METE&' 01 B-7/MW-7 B-2/MW-2 I •e• mow. J ' •� I + i'4 �. 4 Fl t L]PbR IDEW' I e4 � A, GLJ S 7Y /—w • , WALL CH TP-1T ID P LOvA I ' 4 4'r�41rm P CT INSIDE � SPATE 1W TR EE , ' '• .6 w �iaAPE+TPI� f TP-1 A 4 ' ,•• ��■ UN $Ei0LIN0 P13wER ' :p + = p LINE ASN ED r Y �� &CURR"MCITTYA1PtS B-8/MW-8 r �', ° t 37ANGARA9 •, ■ I p- � TP-4 � ■ I 4' x 4' STREET TREE PP, 3E D B: ILL71N9 r TP-2A I t9 LL INUC R TP-2B T j, B-6/MW-6 a� WALLPER MAXNE(ARCH Poe To PLUMBING B-4/MW-4 IE, iL^,S} T TP-3 "is c of MI N B-5/MW-5 !. I I � , r 3$•O SEE zj- PaR B-9/MW-9ILIATIOK $ ` I I B-3/MW-3 SHORINS PLAN&VMLL BE i / _ - Q r n a•a • I AEQUIRED IN FUTURE + PHASES OF C ESH3N 4 i + REPLACE LB45 i ► i i BUILDING LAYOUT AND GRADING SMEM ENT DRAINAGE PER PLUMBING BASEMENT / I1A FFE ■ 31,0 , F79 STEP - =VARIES 32.7 UTILITY RCIAM FFE ■ 37,a CON NECT AMP ➢RAINS PER PLUMBING PLAN TYPE lice r 3a.a J Q- 30 LF "' 31 DETENTION SYSTEM IE-SCZ TO PUBLIC STORM TYPE Il CB W1 FLOW 5YS7EM PER DRAINAflE PLAN CONTROL STRUCTURE CONTROL 122" W� ■ 30J BASEMENT PLAN N 30 0 15 30 SCALE IN FEET REFERENCE: PRELIMINARY GRADING AND UTILITY PLAN, SHEET C3.1, PREPARED BY CG ENGINEERING, DATED OCTOBER 6, 2016. A 60 � B-1 (OFFSET 23' SE) B-3 (OFFSET 58' SE) � SILTY SAND, SOME 50 GRAVEL (FILL) SAND, TRACE TO SOME SILT (GLACIAL OUTWASH) 40 27 LL1 ?------- W? ------- LL z 30 ? - z 5-22-17 40 O 6-7-17 20 50/5" Q > ? J? ------ WD W 10 50/6" TD=35' U -10 0 10 20 -- 30---------- ?----------- - B-4 (OFFSET 58' SE) SILTY SAND, SOME GRAVEL (WEATHERED GLACIAL TILL) SILTY SAND, SOME GRAVEL (FILL) 57 \ B-2 (OFFSET 45' NW) --� - % 33 5732 65 FFE 31 FEET 67 ANTICIPATED CUT DEPTH 37 GROUND SURFACE 30 SILTY SAND, SOME 54 ---- -___-------- ?------------- 22-17 9-14-17 GRAVEL (GLACIAL TILL) 9J4=1a-�- s WD 36 WD 50/3" WD 59 SAND, WITH SILT & __------- GRAVEL (GLACIAL TILL) 50/6"50/6" ---- --- ?----- ---------- 62 ---------------------------- - -------------- 50/6" 50/3° 58 - -- - - - ------------ ? 37 SAND, TRACE TO SOME SAND, SOME SILT 56 SILT, TRACE GRAVEL 51 (GLACIAL ADVANCE TD=36.5' (GLACIAL ADVANCE TD=36.5' OUTWASH) TD=35' OUTWASH) 30 40 50 60 70 80 90 DISTANCE IN FEET 100 110 120 130 Al F- 60 50 40 L1 LLJ LL 30 z z O 20LLJ Q J LLI 10 I -�- -10 140 SOLIDER PILE SHORING DESIGN PARAMETERS ULTIMATE PASSIVE ULTIMATE PASSIVE ACTIVE EARTH ACTIVE EARTH PRESSURE ABOVE PRESSURE BELOW PRESSURE RESISTENCE ABOVE PRESSURE RESISTANCE BELOW ULTIMATE SKIN FRICTION, ULTIMATE END BEARING, BACKSLOPE GROUNDWATER GROUNDWATER TOP OF WALL 1 V xH FINISHED GRADE AT BOTTOM OF EXCAVATION H Pa DEPTH TO GROUNDWATER VARIABLE BASED ON GROUNDWATER BOTTOM OF EXCAVATION ELEVATION FOR SHORING ELEVATION DESIGN: 26 FEET 15 :Li• L •.ir . it n Sri' PP Pa Z (8- MIN.) PASSIVE I ACTIVE PRESSURE # D PRESSURE CANTILEVER PRESSURE DIAGRAM NOTES: 1. ALL DIMENSIONS IN FEET. 2. PASSIVE LATERAL EARTH PRESSURE PRESENTED HEREIN ARE ULTIMATE. AN APPROPRIATE SAFETY FACTOR SHOULD BE APPLIED. 3. PASSIVE PRESSURE APPLY OVER TWO CONCRETED PILE DIAMETERS OR PILE SPACING, WHICHEVER IS LESS. 4. ACTIVE PRESSURE APPLIES OVER PILE SPACING ABOVE EXCAVATION BASE AND OVER ONE PILE DIAMETER BELOW EXCAVATION BASE. MAR-VEL MARBLE REDEVELOPMENT 5.SHORING DESIGN MUST SATISFY FORCE AND MOMENT EQUILIBRIUM 202 Man Street ANALYSES. Edmonds, Washington 6. SEE REPORT TEXT AND FIGURE 5 FOR CALCULATION OF SURCHARGE LOADS LATERAL EARTH PRESSURES ACTING ON THE WALL, AND FOR ADDITIONAL RECOMMENDATIONS. TEMPORARY SOLIDER PILE WALL 7. FOR TRAFFIC SURCHARGES, USE 2 -FOOT EQUIVALENT SOIL SURCHARGE DATE: October 2017 Job No. 1798.01 Zipper Geo Associates, LLC FIGURE 19019 36th Ave. W.,Suite E Lynnwood, WA, 98036 SHT. 1 of 1 x=mD 6h MlIIAIT I llAM (FOR m > 0.4) 1.77q m 2 n 2 z=nD 6h = D 2 - (m2+ n2)3 D (FOR m < 0.4) 0.28q n 2 6h = D 2 - (0.16 + n2)3 BASE OF EXCAVATION �L2� q, Ib per ft2 x=mD� %\/\ 711 z=nD LINE LOAD D PRESSURE Gh q, Ib per ft2 6h BASE OF EXCAVATION 6'h =6h COS (1.1"O) q 6h (7'h O PLAN VIEW OF WALL O in degrees STRIP LOADING PARALLEL TO EXCAVATION 6h = 2�q ((3- sin R cos 2a) a and R in radians LINE LOAD (FOR m > 0.4) 1.28q M 2 n 6h = D - (m2+ n2)2 (FOR m <_ 0.4) _ q 6h D 0.2n (0.16 + n2)2 UNIFORM LOAD DISTRIBUTION 6h = (Ka or Ko) q q = Vertical pressure in psf Ka (Active) = Tan 2(45 - 0/2) Ko (At Rest) = 1 - Sin 0 O = 36' BASE OF EXCAVATION APPENDIX A FIELD EXPLORATION PROCEDURES AND LOGS FIELD EXPLORATION PROCEDURES Our field exploration included nine borings and four test pits completed between April and September 2017. The approximate exploration locations are presented on the enclosed Site and Exploration Plan, Figure 2. Boring locations and ground surface elevations were provided to ZGA by Pacific Coast Surveys, Inc. Test pit exploration locations were determined in the field by measuring distances from existing site features with a fiberglass tape relative to a Topographic and Boundary Survey prepared by Geo Dimensions dated April 11, 2016. Ground surface elevations at the test pit locations were interpolated from topographic lines presented on the Topographic and Boundary Survey. The vertical datum is reported as NAVD 88. As such, the exploration locations and elevations should be considered accurate only to the degree implied by the measurement methods. The following sections describe our procedures associated with the explorations. Descriptive logs of the explorations are enclosed in this appendix. Soil Boring Procedures Borings were advanced using hollow -stem auger drilling methods by an independent drilling companies working under subcontract to our firm. Borings B-1/MW-1 and B-1/MW-2 were advanced using a limited -access, track -mounted drill rig operated by Geologic Drill, Inc. Borings B-2/MW-2 through B-9/MW-9 were advanced using a truck -mounted drill rig operated by Environmental Drilling, Inc. A geologist from our firm continuously observed the borings, logged the subsurface conditions encountered, and obtained representative soil samples. All samples were stored in moisture -tight containers and transported to our laboratory for further visual classification and testing. Throughout the drilling operation, soil samples were obtained at 2.5- to 5-foot intervals by means of the Standard Penetration Test (ASTM: D-1586). This testing and sampling procedure consists of driving a standard 2-inch outside diameter steel split spoon sampler 18 inches into the soil with a 140-pound hammer free falling 30 inches. The number of blows required to drive the sampler through each 6-inch interval is recorded, and the total number of blows struck during the final 12 inches is recorded as the Standard Penetration Resistance, or "blow count" (N value). If a total of 50 blows are struck within any 6-inch interval, the driving is stopped and the blow count is recorded as 50 blows for the actual penetration distance. The resulting Standard Penetration Resistance values indicate the relative density of granular soils and the relative consistency of cohesive soils. The enclosed boring logs describe the vertical sequence of soils and materials encountered in each boring, based primarily upon our field classifications and supported by our subsequent laboratory examination and testing. Where a soil contact was observed to be gradational, our logs indicate the average contact depth. Where a soil type changed between sample intervals, we inferred the contact depth. Our logs also graphically indicate the blow count, sample type, sample number, and approximate depth of each soil sample obtained from the boring, as well as any laboratory tests performed on these soil samples. If groundwater was encountered in a borehole, the approximate groundwater depth, and date of observation, is depicted on the log. Groundwater monitoring wells were installed in both explorations completed for this project. Monitoring well construction details are presented on the boring logs. Post exploration groundwater levels measured in the monitoring wells are reported on the boring logs and in the report text. The boring logs presented in this appendix are based upon the drilling action, observation of the samples secured, laboratory test results, and field logs. The various types of soils are indicated as well as the depth where the soils or characteristics of the soils changed. It should be noted that these changes may have been gradual, and if the changes occurred between sample intervals, they were inferred. Test Pit Procedures An independent contractor working under subcontract to the Owner excavated the test pits using a tracked -mounted excavator. A geologist from our firm continuously observed the test pit excavations, logged the subsurface conditions, and obtained representative soil samples. The samples were stored in moisture tight containers and transported to our laboratory for further visual classification and testing. After we logged each test pit, the operator backfilled each test pit with excavated soils tamped into place. Some settlement of the backfill should be expected over time. The enclosed test pit logs indicate the vertical sequence of soils and materials encountered in each test pit, based primarily on our field classifications and supported by our subsequent laboratory testing. Where a soil contact was observed to be gradational or undulating, our logs indicate the average contact depth. We estimated the relative density and consistency of in situ soils by means of the excavation characteristics and by the sidewall stability. Our logs also indicate the approximate depths of any sidewall caving or groundwater seepage observed in the test pits, as well as all sample numbers and sampling locations. Boring Location: See Figure 2, Site and Exploration Plan Drilling Company: Geologic Drill Bore Hole Dia.: 6-Inch Top Elevation: 40.88 Feet Drilling Method: H.S.A. Hammer Type: Cathead B-1/MW-1 Date Drilled: 4/28/2017 Drill Rig: Mini -Track Logged by_: JPG E a) SOIL DESCRIPTION �� E J n U) � - a 2 (D PENETRATION RESISTANCE (blows/foot) co o U m 0) ~ The stratification lines represent the approximate boundaries between soil types. The transition may be gradual. Refer to report text and appendices for additional information. Standard Penetration Test Q Hammer Weight and Drop: 0 20 40 60 6 inches of concrete (III ',II IIIIIIIII IIII ..- Loose to medium dense, wet grading to saturated, mottled IIII III IIIIIIIII IIIIII r r - gray -brown, silty SAND, some gravel (Possible Fill) PID < 1 m ( ppm) --------------------------- Medium dense, moist to wet, gray -brown, silty SAND, some T S 1 I 14 +I 27 ��T r� JJJ�1 r�7 7TTTT 'j'TIf 11.1111111 1 1 1 1 TT�TTTT 1LLLLLL IIII 1 '- gravel (Weathered Glacial Till) (PID < 1 ppm) -------------------------------------------- Dense, moist to wet, gray, fine to medium SAND, trace to S-2 18" 38 (IIIIII IIt^tIII �4 t+ IIIIIIIII IIIIIIII +++++++ (IIIIII (IIIIII +++ + r - some silt. Glacial Outwash PID < 1 ( )( ppm) -------------------------------------------- -+7rt-trtrtrt rtrty-tttttt tt.-rr Medium dense, moist, gray -brown, silt SAND, some ravel 9 Y Y 9 (Weathered Glacial Till) (PID < 1 ppm) Dense, moist, gray to gray -brown, silty SAND, some gravel S-3 18" I 1 1 1 1 1 27 GSA -1-I �-f7 '...i111111 11iii11 777 77TTT IIIIIIIII IIIIIIIII TTT-71-1-1-� 1 1 1 1 1 1 1 IIIIIIII iii1111i (Weathered Glacial Till) (PID < 1 ppm) _ _ _- s-a T 16"< 1 Q + ++ + _ _ 72 VeryDense, moist gray, silt SAND, some ravel Glacial Till g Y, Y g ( ) (PID <1 ppm) ''-1- 1- ...11 :ill -+tttttttt IIIIIIIII tt+� IIII Dense, wet, gray with slight iron oxide staining, silty SAND, some gravel (Glacial Till) (PID < 1 ppm) S-5 16" I to 40 GSA 7 T rt��trr ...I1 �1i r iI11IIi11 rrrrTTT` IiI1111- T_7T_TT.7_ �� Q II...II IIIIiII i IIIIIIIII iI11IIi11 IIII IiI1 ''...i1i i �rtrtrtrtrt IIIIIIIII rtrtrt7rtrt-rrtr IIII trrrrr -177-1-7-T 'IIIIII - 7.7 7777 T _ '(IIII TT7TT77_ I7 IIIIIIIII Very dense, moist, gray to gray -brown, silty SAND, some T S-s I 10.. 50/5" Q gravel (Glacial Till) (PID < 1 ppm)- '...1111111 IIIIIIIII IIII 11iii1i iI11IIi11 IiI1111 1.. -1-1-f fitfi t t t..tt t tt.tt- - .:.. 11iii1i . '.-177-17_T7 iI11IIi11 IiI1111 _... 777T7TTTT TTTTTTT:- SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm) I2-inch O.D. split spoon sample 0 Clean Sand O % Water (Moisture) Content 3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit Grout/Concrete Natural Water Content ® Screened Casing Mar-Vel Marble TESTING KEY n Blank Casing 202 Main Street GSA = Grain Size Analysis V Groundwater level at Edmonds, WA time of drilling (ATD) or 200W = 200 Wash Analysis_ on date of Date: October 2017 Project No.: 1798.01 Consol. = Consolidation Test measurement. Zipper Geo Associates BORING Att. = Atterberq Limits B-1/MW-1 19019 36th Ave. W, Suite E LOG; Lynnwood, WA Page 1 of 2 Boring Location: See Figure 2, Site and Exploration Plan Drilling Company: Geologic Drill Bore Hole Dia.: 6-Inch Top Elevation: 40.88 Feet Drilling Method: H.S.A. Hammer Type: Cathead B-1/MW-1 Date Drilled: 4/28/2017 Drill Rig: Mini -Track Logged by_: JPG E a) SOIL DESCRIPTION J'u Q Q_ 10 E � - a (2 0 PENETRATION RESISTANCE (blows/foot) co o U ° m U) °) The stratification lines represent the approximate boundaries between soil types. The transition may be gradual. Refer to report text and appendices for additional information. Standard Penetration Test Q Hammer Weight and Drop: 20 40 60 Very dense, moist to wet, gray to gray -brown, SAND, with silt and gravel (Glacial Till) (PID < 1 ppm) -------------------------------------------- S-7 :; IIIIIIII I 50/5" :••_::. � — ��J��J�� _I_I�J�11 -LLLC-LL (IIIIIII IIIIIIIII IIIIIII' rY gray, some silt,trace(Glacial) Advance Outwash) (PID < 1 s $ + 12 T _ IIIIIIIII IIIIIIII .IIIIIIII IIIIIIIII III ii i II IIIIIII' i I i 50/5" GSA �i -t -t -trt *' rtrttt7 m Moderate to severe heave encountered PP )( ) IIIIIIIII IIIIIIIII IIIIIII'' IIIIIIII IIIIIII L! . _I . II II 1 IIIIIIIII (III -1 L_1 (III ill 7777777 _ Iii1111' ii1111' ii1111' j1111, Boring completed at about 35 feet. Perched groundwater observed at about 3 feet ATD. - Groundwater observed at about 27 feet ATD. IIIIIIII Groundwater measured at 14.63 feet on 5/22/2017. rl I i--i I .III 77rt rt 7 i Groundwater measured at 14.37 feet on 5/26/2017. Groundwater Measured at 14.85 feet on 6/7/2017. IIIIIIII 7��71 .III �- (III' T7T7 Well Tag # BIK 772 LI I f_L_I I ..IIIIIIII .IIIIIII JJ 11i 111 1111, ICI I IIIIIII IIIIIII II ill IIIIIII r l I-1-I-I IIIIIIII (III y rt, (III IIIIII' 14 t7777 IIIIII' —FT7777- ( I I I 17-7- (III 'IIIII i!IIIIL.I IIIIIIIII k k i i' -777777 7 _ IIIIII' IIIIIII' L.L.IIIII IIIIIII' IIIIIIII IIIIIIII IIIIIIIII IIIIIIIII IIIIIIIII IIIIIIIII IIIIIIII IIIIIIIII IIIIIIIII IIIIIIIII IIIIIII' IIIIIII' IIIIIII' IIIIIIIII IIIIIII' I-III-III-1-III IIIIIIII I I I h IIIIIIIII F + f f Y IIIIIII' IIIIIIIII rrrl 1-t-i-I I--i-i-177rt.�.77 IIIIIIIII IIIIIII' rtrtrtrtrtrtrt _.... 777-T77-T SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm) I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content 3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit Grout/Concrete Natural Water Content ® Screened Casing Mar-Vel Marble TESTING KEY n Blank Casing 202 Main Street GSA = Grain Size Analysis V Groundwater level at Edmonds, WA time of drilling (ATD) or 200W = 200 Wash Analysis _ on date of Date: October 2017 Project No.: 1798.01 Consol. = Consolidation Test measurement. Zipper Geo Associates 19019 BORING BANW-1 Att. = Atterberq Limits 36th Ave. W, Suite E Lynnwood, LOG; WA Page 2 of 2 Boring Location: See Figure 2, Site and Exploration Plan Drilling Company: Geologic Drill Bore Hole Dia.: 6-Inch Top Elevation: 39.51 Feet Drilling Method: H.S.A. Hammer Type: Cathead B-2/MW-2 Date Drilled: 4/28/2017 Drill Rig: Mini -Track Logged by_: JPG SOIL DESCRIPTION - PENETRATION RESISTANCE (blows/foot) �� E co o 0) Standard Penetration Test E The stratification lines represent the approximate boundaries J n a Q Hammer Weight and Drop: U a) between soil types. The transition may be gradual. Refer to ~ report text and appendices for additional information. U) � 2 m (D 0 20 40 60 4 to 5 inches of concrete '..II ',II IIIIIIIII IIII Medium dense, wet, mottled gray -brown, silty SAND, some III IIIII I11 114 rtI tIrI -r-r-1II-1II'll r r - gravel (Possible Fill) (Hydrocarbon Odor at Tip of Sampler) (PID = 43 ppm) s-1 114 1 1 IIIIIII 11 1 1 I I 1 1 IIIIIIIII 1 1 1 1 1 1 IIIIIII 32 ��7T�T TTTTT�TTT TTTT1 - -------------------------------------------- III1111 11111 111 Illlll Verydense, moist, gray, silt SAND, some ravel Glacial Till g Y, Y g ( ) 1 JJLJ�11 '..IIIIIII '..IIIIIII LL-L111--- IIIIIIIII IIIIIIIII LILLLLL IIIIIII- IIIIIIII x (Hydrocarbon Odor) (PID = 109 ppm) S-2 181, 14-+ '.....I11 III -+-F-+++++++ IIIIIIIII +++ -+ - IIII 65 Illlill -1 trtttrtrt IIIIIIIII rtty- t t tt-tt IIII t t..t t Verydense, moist, gray, silt SAND, some ravel Glacial Till 9 Y Y 9 ( ) T S3 I 18�� 1 1 67 -1TT�IT-f7 7TTT T TTTT TTT-TTI-T (Hydrocarbon Odor) (PID = 104 ppm) Very dense, moist, gray, silty SAND, some gravel (Glacial Till) (Faint Hydrocarbon odor) (PID = 45 ppm) 11 s-a T I 18 '...illllll I. I I I I I I I IIIIIIIII I I I I I I I I I IIIIIT- I I 1 1 1 1 1 37 -i++++ - - '...Illlill .,I111111 IIIIIIIII IIIIIIIII IIII�I. IIII -------------------------------------------- Dense, wet to saturated, gray -brown SAND, with silt and gravel. (Glacial Till) (PID = 10 ppm) T s-s 11 10 .,I111111 IIIIIIIII I111111: ss 7-�T-irt�� ''...Illlili ''...I1 ill -ttr-r-r7-r-r-r IIIIIIIII IIIIIIIII -r-r-rrrrr.� _ IIIIIII- IIIIIII- n 0 �� ....III1111 * 11 II I +��++ IIII ......Illlill IIIIIIIII llil�...... ''...," iili �rtrtrtrtrt ''...Iliiili 11,11,111 ",44 4 IIIIIIIII IIII ..- trrrr r . . (IIIIIIIII ''...Iliiili IIIIIIIII Illlllll -177-1-7-T7 ..IIIIIII TTTTTTTTT Ill�llil� TTTTTi-T '- lill�ll- Very dense, wet to saturated, gray -brown SAND, with silt and s-6 T csa gravel (Glacial Till) (PID = 6 ppm) 12 I 1 - -- illllll _ illllllll _ 11'.. sots° �Illlill ''...Iliiili IIIIIIIII IIIIIIIII III IIIIIII- ----------------------------------------- 1.. -1-1 _f ',IIIIIII fitfi t t t..ttt IIIIIIIII .t'.r't't. - :.. Illlil ".. Very dense, saturated, gray SAND, some silt (Glacial Advance '...IIIIII IIIIIIIII IIIIIIII �� T77TTTTTT TTTTrTr;- Outwash) (PID = 2 ppm) SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm) I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content 3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit Grout/Concrete Natural Water Content ® Screened Casing Mar-Vel Marble TESTING KEY n Blank Casing 202 Main Street GSA = Grain Size Analysis V Groundwater level at Edmonds, WA time of drilling (ATD) or 200W = 200 Wash Analysis_ on date of Date: October 2017 Project No.: 1798.01 Consol. = Consolidation Test measurement. BORING Zipper Geo Associates B-2/MW-2 Att. = Atterberq Limits 19019 36th Ave. W, Suite E LOG; Lynnwood, WA Page 1 of 2 Boring Location: See Figure 2, Site and Exploration Plan Drilling Company: Geologic Drill Bore Hole Dia.: 6-Inch Top Elevation: 39.51 Feet Drilling Method: H.S.A. Hammer Type: Cathead B-2/MW-2 Date Drilled: 4/28/2017 Drill Rig: Mini -Track Logged by_: JPG E a) SOIL DESCRIPTION J'u Q 10 E � - a ( 2 0 PENETRATION RESISTANCE (blows/foot) co o U 3 ° m U) °) The stratification lines represent the approximate boundaries between soil types. The transition may be gradual. Refer to report text and appendices for additional information. Standard Penetration Test Q Hammer Weight and Drop: 20 40 60 Very dense, saturated, gray SAND, some silt ,(Glacial Advance Outwash) (PID = 2 ppm) `----------------------------------------- S_7 1$ sots Very dense, wet to saturated, gray, silty SAND, some gravel (Glacial Till) (PID = 2 ppm) _I 7I I I I I_ -1-T-1-17-1.7-1 l 77.7-T7T- , -------------------------------------------- -LLLLLLL _d-i L11' (IIIIIII (IIIIIIII IIIIIII' Dense, saturated, gray, fine to medium SAND, trace to some silt (Glacial Advance Outwash) (PID < 1 ppm) S-8 18 :. ..:� ' IIIIIIII .IIIIIIII IIIIIIII IIIIIIIII IIIIIIIII IIIIIII' IIIIIII' 37 rrr -t I IIIIIIII IIIIIIII IIIIIIIII 1 i L I L.i__1 I__L__I IIIIIIII Illliill LLLLLLI Illliill Illil W rt� 1"T dill IIII _ -1-1-1-77 IIIIIIIII I I�illl�_ II II I _ J� _ II II rt rt rt rt rt t t r IIIIIII' IIIIIII' 7777777- _ IIIIIII' I i1111 IIIIIII iillll' _ILJ1aJ fllllll' iillll — •'•�'' '•�' :•:_:. — Boring completed at about 35 feet. Groundwater observed at about 15 feet ATD. -I - Groundwater measured at 13.18 feet on 5/22/2017. Groundwater measured at 13.88 feet on 5/26/2017. rl I i--i i7rt 7 i Groundwater measured at 13.20 feet on 6/7/2017. Groundwater measured at 15.56 feet on 10/2/2017. I I I I I I I I I I I I I I I T7T7 Well Tag # BIK 773 LI I f_L_I I ..IIIIIII .IIIIIII �J.L i i 111 1111, I l i IIIIIII .IIIIIII IIIIIII iI ill IIIIIII 1 r l I-1-I-I � IIIIIIII IIII � y rt IIII IIIIII' rrt t7777 IIIIII' IIIIIIII IIII _ 7-f_ _. IIII '(IIII i!IIIIL.I IIIIIIIII IIIIII' -777777 IIIIII' IIIIIII' L.L.IIIII IIIIIII' 71 7r� T IIIIIIII IIIIIIII IIIIIIIII IIIIIIIII IIIIIIIII IIIIIIIII IIIIIIII IIIIIIIII IIIIIIIII -1-1.-I -4 4 IIIIIIIII IIIIIII' IIIIIII' -4 4.4 4 4++ 1 IIIIIII' .IIIIIIII IIIIIIIII IIIIIII' AL I I--1 I I _1-l-f-h IIIIIIIII -h-F-F-1 i Y IIIIIII' .IIIIIIII IIIIIIII rl 1-t-i-I I--i-I-177rt.�.77 IIIIIIIII IIIIIII' rtrtrtrtrtrtrt SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm) I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content 3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit Grout/Concrete Natural Water Content ® Screened Casing Mar-Vel Marble TESTING KEY n Blank Casing 202 Main Street GSA = Grain Size Analysis VGroundwater level at Edmonds, WA time of drilling (ATD) or 200W = 200 Wash Analysis_ on date of Date: October 2017 Project No.: 1798.01 Consol. = Consolidation Test measurement. Zipper Geo Associates 19019 BORING B-2/MW-2 Att. = Atterberq Limits 36th Ave. W, Suite E Lynnwood, LOG: WA Page 2 of 2 Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 6-inch Top Elevation: 41.00 feet Drilling Method: HSA Hammer Type: Auto B-3/MW-3 Date Drilled: 9/12/2017 Drill Rig: B-61 Truck Logged by_: JST E a) SOIL DESCRIPTION J'u Q 10 E 0� � - a (2 PENETRATION RESISTANCE (blows/foot) co o U ° m U) °) The stratification lines represent the approximate boundaries between soil types. The transition may be gradual. Refer to report text and appendices for additional information. Standard Penetration Test Q Hammer Weight and Drop: 0 20 40 60 IIII ',II IIIIIIIII IIII ..- 11111111 i '... IIIIIIIII Illlli -17Y�rt-I-Y '..IIIIIII rtrtYYTY7-tT IIIIIIIII rtTTYT r r - :_... (IIIIIII Medium dense, moist, mottled gray -brown, silt SAND, trace 9 Y Y to some gravel, no odor, PID <1 ppm. (Weathered Glacial Till) S-1 181, 30 -1TT-1T-f7 T 7T T TTTT �1 1 1 1 TT TTTTT 1 1 1 1 1 1 -------------------------------------------- Dense, damp, gray,sand SILT, some ravel, no odor, PID <1 Y 9 ppm. (Glacial Till) T S-2 I 18 11 '..IIIIIII '..IIIIIII --- IIIIIIIII IIIIIIIII LLLLLLL IIIIIII (IIIIIII 33 -1-1 L-I+ '....III III II II I i-++++-+ .- IIII '..IIIIIII 1-17rt�rtrtrt '..IIIIIII IIIIIIIII rtrt7-rtrtt*trt IIIIIIIII IIII ..- t t r r r,, IIIIIII Very dense, moist, gray, silty SAND, with gravel, no odor, PID <1 ppm. (Glacial Till) S-3 T 12„ I 1 IIII IIIIIIIII IIIIIII _... 75 T-f7 '..IIIIIII '..IIIIIII T-TTTTTTTT IIIIIIIII IIIIIIIII TTTTTTT.._� (IIIIIII IIII1LIII I I I...I...I 'I.... L �- '....1111�11 �4.4+ 4- 1i11111 IIII '..IIIIIII .''...IIIIIII 111111111 IIIIIIIII IIII '. IIII Medium dense, wet, gray with oxidation mottling, silty SAND, some gravel, no odor, PID <1 ppm. (Glacial Till) T sa 12 -11 '..IIIIIII (IIIIIII IIIIIIiI�i 30 1.-IYTrt�7 '..1111111 '..II ill L iY 7rtYYYT-t,..._ IIIIIII IIIIIII T-r77T77'r7. (IIII ',..I �� ....1111111 1i ii i - IIII ...IIIIIII IIIIIIIII IIII Sample B-3/MW-3 @15 1/2-16' submitted for analysis for IIIIIIIII IIII VOCs. ...1111111 �rtrtrtrtY '..IIIIIII rtrtYYYrt-rrtr IIIIIIIII trrr t- r 1111111111 > Groundwater observed on rods at 18 1 /2 feet. ..11 -1TT111�I-177 II1111I11 - -r 7 77T - IIIIIIIII Tr-77-1- r-T - 0 1111� 11111 111111 Very dense, saturated, gray -brown with oxidation mottling, S-5 I 81, 50/3" silty SAND, some gravel, no odor, PID <1 ppm. (Glacial Till) - -- '...1111111 '..II -� - IIIIIIIII IIII I1I1I+ "I'll11111111 IIIIIIIII +-I - a +++++ Illlli +++11- 11 '..IIIIIII IIIIIIIII IIIIIII Very dense, saturated, dark gray, gravelly SAND, with silt, no odor, PID <1 ppm. ( Glacial Till) '..IIIIIII 11��1�� ...1111I11 '. IIIIIIIII fifi� t t t ttfi IIIIIIIII IIII fifiYtr IIIIIII- 75 YTTTTTTTT TTTTTTT SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm) I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content 3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit Grout/Concrete Natural Water Content ® Screened Casing Mar-Vel Marble TESTING KEY n Blank Casing 202 Main St. GSA = Grain Size Analysis VGroundwater level at Edmonds, WA time of drilling (ATD) or 200W = 200 Wash Analysis_ on date of Date: October 2017 Project No.: 1811.22 Consol. = Consolidation Test measurement. Zipper Geo Associates BORING Att. = Atterberq Limits 13-3/MW-3 19019 36th Ave. W, Suite E LOG: Lynnwood, WA Page 1 of 2 Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 6-inch Top Elevation: 41.00 feet Drilling Method: HSA Hammer Type: Auto B-3/MW-3 Date Drilled: 9/12/2017 Drill Rig: B-61 Truck Logged by_: JST E a) SOIL DESCRIPTION �� E J n U) � - a 2 (D 0 PENETRATION RESISTANCE (blows/foot) co o U —° m 0) ~ The stratification lines represent the approximate boundaries between soil types. The transition may be gradual. Refer to report text and appendices for additional information. Standard Penetration Test Q Hammer Weight and Drop: 20 40 60 Very dense, saturated, dark gray, silty GRAVEL with sand, no odor PID<1ppm.IGlacialTillj---------------------- Sa 18^ ;'.; I.i III 77 i_t IIIIIIIII 7 rt 7 7 Ilillll' 12 .III 1 1-1-17- 1 1 1 Very dense, saturated, gray -brown, gravelly SAND, some silt, no odor, PID <1 ppm. (Glacial Advance Outwash) S-8 I 18" ;.. -L LL 12 i 1 1 1 1 1 1 1 1 1 1 Sample B-3/MW-3 28 1/2-29' submitted for analysis for p @ Y VOCs. — 111111 1 1 111111111 1 II1111. Verydense, saturated, gray -brown, SAND, some silt, no odor, g Y PID <1 ppm. (Glacial Advance Outwash) Very dense, saturated, gray, SAND, trace to some silt, trace gravel, no odor, PID <1 ppm. (Glacial Advance Outwash) S-9 15" 10 12 •' 1 1 11 i-F- -t I Illilill IIIIIIIII i 1 i i L.i__1 I__1__1 IIIIIIII LLLLLLI 11111111 Iii11 rt � 11111 I 1 -1-7-7-77 IIIIIIIII 1 II II i _ J-- _ 11 II 4 -t rt t t t t t IIIIIII' 7777777- _ 111111' 1 i1111 IIIIIII ii1111' f _-1- 11 llllll' i i 50/3" 55 - ''•�'' :•:_: - 'IIIIIII I Boring completed at about 36 1/2 feet. ri i i--i 7rt -r 1 1 1 J t T.... Groundwater observed at approximately 18 1 /2 feet ATD b s. Groundwater measured at 16.15 feet on 9/12/17, immediately �I I I I �- 1 1 I 1 1 1 T77T after well installation, from TOC. Groundwater measured at 16.22 feet on 9/14/17 from TOC. 1111.11. Groundwater measured at 16.52 feet on 10/2/17 from TOC. Ecology Well Tag ID # BIZ 381. I111ii1. Iliiiil �I �11 �I rl I-t-I-I 1111 -yrt 1liliiiii ,.rtrtttt 1 tTl 1111 I� - _. 1111 ii1111 -77T4-T _ ii1111 7i r-7r -. iiliiiil IIIIIIII -4 4 IIIIIIIII -4 4.4 4 4++ 1 IIIIIII' IIIIIIII IIIIIIII 111111' IIIIIIIII IIIIIIII' .IIIIIIII IIIIIIII I rl I_f_I_I I- IIIIIIII IIIIIIIII -I-I-17 7 rt.�.� � IIIIIIIII IIIIIIIII 7rt7 trtrtYrtY IIIIIIIII IIII I I I I I I I I I I I I I I I I SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm) I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content 3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit Grout/Concrete Natural Water Content ® Screened Casing Mar-Vel Marble TESTING KEY n Blank Casing 202 Main St. GSA = Grain Size Analysis V Groundwater level at Edmonds, WA time of drilling (ATD) or 200W = 200 Wash Analysis_ on date of Date: October 2017 Project No.: 1811.22 Consol. = Consolidation Test measurement. Zipper Geo Associates BORING Att. = Atterberq Limits B-3/MW-3 19019 36th Ave. W, Suite E LOG: Lynnwood, WA Page 2 of 2 Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 6-inch Top Elevation: 41.32 feet Drilling Method: HSA Hammer Type: Auto B-4/MW-4 Date Drilled: 9/12/2017 Drill Rig: B-61 Truck Logged by_: JST E a) SOIL DESCRIPTION J'u Q 10 E 0 � - a PENETRATION RESISTANCE (blows/foot) co o U 3 ° m U) -- The stratification lines represent the approximate boundaries between soil types. The transition may be gradual. Refer to report text and appendices for additional information. Standard Penetration Test Q Hammer Weight and Drop: 0 20 40 60 IIII ',II IIIIIIIII IIII ..- (IIIIIII i '... IIIIIIIII Illlii -17Y�rt-I-Y '..IIIIIII rtrtYYTY7TT IIIIIIIII rTTYT r r - :_... (IIIIIII Verydense, moist, light brown, SAND with silt and ravel, no 9 g odor, n0 PID. (Glacial Till) Verydense, dam light brown, sand SILT, with ravel, no p' g Y g odor, PID <1 ppm. (Glacial Till) g-1 I 15" 1I T S-2 I 16 11 57 57 -1-7-7-777 I I I I I I I JJJ��1 '..IIIIIII '..IIIIIII 77-T-TTTTTT ( I I I I I I I 11.11111.11 IIIIIIIII IIIIIIIII TTTTTTT� I I I I I I I 1LLLLLLL (IIIIIII IIIIIIII�1 -1-I I++ '....III III +-I+++++++ IIIIIIIII + ++I-I-+i-A.. IIIIIIIII '..IIIIIII ,I-17rt-trtrtrt '..IIIIIII IIIIIIIII rtrtYtttttt IIIIIIIII IIIIIIIII tt.rrrrr.�r. (IIIIIII Very dense, damp, light brown, sandy SILT, with gravel, no odor, PID <1 ppm. (Glacial Till) s-3 T 18° I 1 '..IIIIIII IIIIIIIII IIIIIII _... 70 '...-17T-7T--T '..IIIIIII '..IIIIIII T-TTTTTTTT IIIIIIIII IIIIIIIII TTTTTTT.._7 (IIIIIII IIII1LL '....1111�11 IiIlI1i11 - (IIIIIII '..IIIIIII '..IIIIIII IIIIIIIII IIIIIIIII Illl�i. IIII Very dense, moist to wet, mottled light brown with gray, silty SAND, with gravel, no odor, PID <1 ppm. (Glacial Till) T s-a 1z 11 '..IIIIIII '...-IYTrt�7 IIIIIIIII IIIIIII: sa ''...IIIIII� ''...11 III __ 7rtYYTTTTT IIIIIIIII IIIIIIIII Y77Y7TTT_ TT?-TTTT.L :_... IIIIIII IIIIIII TT7777 ....1111111 Ii ii i IIII ......1111�11 .''...IIIIIII .''...IIIIIII IIIIIIIII IIIIIIIII II�II...... IIII � a '.77rtrtrtrtY IIIIIIIII rtrtYYYT7t-r IIII Yrrrrr'`. � ..IIIIIII -1-ITTT IIIIIIIII (IIIIIII f7 '..IIIIIII TTTTTTTTT III�IIII� TTTTT T' IIIIIII D o 29 Very dense, wet, light brown with oxidation, silty SAND, trace gravel, no odor, PID <1ppm. (Glacial Till) T s-s 11 18° ss ....1111111 _ _ IIIIIIIII _ IIII ......IIII�II IIIIIIIII IIII.. '..IIIIIII IIIIIIIII IIIIIII Very dense, wet, light brown mottled with gray, silty SAND, T s-s I 1z^ 1I11'1111111IIIIII IIII fifitIItIt t tItfiI fififitIIII r 5016^ with ravel, no odor, PID <1 m. (Glacial g pp Glil Till) ( 11 '...IIIIIII . '.-11TYT-1-1 IIIIIIIII IIIIIII YTTT7TTTT T7TTT77 SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm) I2-inch O.D. split spoon sample Clean Sand 0 % Water (Moisture) Content 3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit Grout/Concrete Natural Water Content ® Screened Casing Mar-Vel Marble TESTING KEY n Blank Casing 202 Main St. GSA = Grain Size Analysis VGroundwater level at Edmonds, WA time of drilling (ATD) or 200W = 200 Wash Analysis_ on date of Date: October 2017 Project No.: 1811.22 Consol. = Consolidation Test measurement. Zipper Geo Associates BORING B-4/MW-4 Att. = Atterberq Limits 19019 36th Ave. W, Suite E LOG: Lynnwood, WA Page 1 of 2 Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 6-inch Top Elevation: 41.32 feet Drilling Method: HSA Hammer Type: Auto B-4/MW-4 Date Drilled: 9/12/2017 Drill Rig: B-61 Truck Logged by_: JST E a) SOIL DESCRIPTION �� E J n U) � - a 2 (D 0 PENETRATION RESISTANCE (blows/foot) co o U -° m 0) ~ The stratification lines represent the approximate boundaries between soil types. The transition may be gradual. Refer to report text and appendices for additional information. Standard Penetration Test Q Hammer Weight and Drop: 20 40 60 Very dense, wet, light gray mottled with brown, trace oxidation, silty SAND, trace gravel, no odor, PID <1 ppm. S-7 16° -1-1-1 79 (Glacial Till) -------------------------------------------- I I I I _1_I I I I 1 1 1 �.�.7 1 1 1 1 1 1 1 7T7T7TT Very dense, saturated, light brown, SAND, trace silt with gravel, no odor, PID <1 ppm. (Glacial Advance Outwash) Very dense, saturated, light brown, SAND, trace silt and gravel, no odor, PID <1 ppm. (Glacial Advance Outwash) S-8 18" S-9 18" ••• :'' IIIIIII 11111111 11111111 IIIIIIIII 1 1 1 1 1 1 1 1 1 IIIIIIIII IIIIIIIII IIIII . IIIIIII' IIIIIII' 54 _ — ' :•:_ :.:� ' I I I I I rrr -t I 111i1111 I I I I I I I l-1I -1I IIIIIIIII I rtrt4-1-4 11i1111' •'•�'' IIIIIIIII i1iil_.i__1i �I I I I I I� 111i111 'I 'I -77-17-7-7-77 IIIIIIIII �1liii _I iI I I _ 1111 1111 7777777- . 111111' liiiii I I I I I I I IIIIII' IIIIII' •'•—•• Very dense, saturated, light brown, SAND, some silt, interbed of sandy fine GRAVEL from 35 1/2 to 36 feet, no odor, PID <1 ppm. (Glacial Advance Outwash) S-10 181, !-� ' T I I _IIIII 1 1 !- ' IIIIII A 51 Boring completed at about 36 1/2 feet. r i i I--i i t--i77rt rt t T 1 Groundwater observed at about 19 1/2 feet bgs ATD. Groundwater measured at 16.99 feet below TOC on 9/12/17, IIIIIIIII IIIIIIIIII 11 1 1 1 T7T7 T- l I- I - immediately after well installation. Groundwater measured at 17.07 feet below TOC on 9/14/17. I I I I I _I_I I I L_IJ��J.�� 111 I I I I Groundwater measured at 17.39 feet below TOC on 10/2/17. 49 Ecology Well ID: BIZ 382 111ii1. ��liiiil �1 �11 iiliiiil r.rrl I-f-I-f 1111 rt , 1111 ii1111 1447777 ii1111 1111 -17-7- 1111 1 1 7 1 ii1111 -777777 ii1111 1 1 1 1 1 1 7r�T iiliiiil i l i i 1- IIIIIIIII iiliiiili -I -I.-14 -� -4 4 IIIIIIIII iii1111 4 4.4 4 4 4+ 1 IIIIIII' 11111111 IIIIIIIII IIIIIII' 11111111 IIIIIIIII IIIIIII' r 77777rtrt SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm) I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content 3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit Grout/Concrete Natural Water Content ® Screened Casing Mar-Vel Marble TESTING KEY n Blank Casing 202 Main St. GSA = Grain Size Analysis V Groundwater level at Edmonds, WA time of drilling (ATD) or 200W = 200 Wash Analysis_ on date of Date: October 2017 Project No.: 1811.22 Consol. = Consolidation Test measurement. Zipper Geo Associates BORING Att. = Atterberq Limits B-4/MW-4 19019 36th Ave. W, Suite E LOG: Lynnwood, WA Page 2 of 2 Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 6-inch Top Elevation: 41.20 feet Drilling Method: HSA Hammer Type: Auto B-5/MW-5 Date Drilled: 9/12/2017 Drill Rig: B-61 Truck Logged by: JST E a) SOIL DESCRIPTION J'u Q 10 E 12� � - a D PENETRATION RESISTANCE (blows/foot) co o U 3 ° m U) °) The stratification lines represent the approximate boundaries between soil types. The transition may be gradual. Refer to report text and appendices for additional information. Standard Penetration Test Q Hammer Weight and Drop: 0 20 40 60 -III ',II IIIIIIIII IIII ..- Moist, light brown mottled with oxidation, silty SAND, no odor, PID <1 ppm. (Blow counts overstated, pounding on rock) S-1 2 3" IIII1111 i '... IIIIIIIII Illlii 50/5" -17Y�rt-I-Y I I I I I I I rtYYYYY7-rY I I I I I I I I I rTTYT r r - :_... I I I I I I I --7-1- 77 -T-7-T -T 7 -j--j T T T TT-i--F-IT- - (Weathered Glacial Till).... -------------------------------------------- JJJ�1 '..IIIIIII 11 1 1 1.1.1111.1.11 IIIIIIIII 1 1 L1 1LLLLi_ L IIIIIII recovery. d illi gtidbdtti No recove (Based on drilling action anobserved cuttings, g S-2 I 0" '..IIIIIII IIIIIIIII -IIIIIII 50/6" '...II ...11 IIIIIIIII IIIIIII sample likely driven into silty SAND). (Glacial Till) '...III�I11 IIIIIIIII fill '..IIIIIII -+7rtYrtrtY '..IIIIIII IIIIIIIII YrtY t t t tt t IIIIIIIII IIII t t- f- IIIIIII Very dense, moist, light brown, silty GRAVEL, with sand, no S-3 I 8" •. '..IIIIIII IIIIIIIII IIIIIII _... k50/6" '...-1-ITYY--T '..IIIIIII '_-IIIIIII T-lTTTTTTT IIIIIIIII IIIIIIIII TTTTTI-T.._� -IIIIIII IIIIIII- —A := odor, PID <1 ppm. (Glacial Till) ++ '...IIIIIII + ++ -+ IIIIIIIII + + + - - -IIIIIII .• — �• — -IIIIIII IIIIIIIII IIIIIIIII IIIIIIIII Illl�i IIII '. -IIIIIII IIIIIIIII IIIIIII: ''.....IIIiIII ''...IIIIIII YYYYYTTTT IIIIIIIII IIIIIIIII TT?-TTTT� _.. -IIIIIII -IIIIIII — li�� Iil�lill Ilil II Dense, moist to wet, light gray to brown with oxidation, silty SAND, some gravel interbedded with sandy GRAVEL some silt, no odor, PID <1 ppm. (Glacial Till)++++- - y •.,�,•:• ' 4 4 1.. G L L - 33 •:.jam: .IIIIIII -1�rtYYrtY '....IIIIIII IIIIIIIII YYYYYrt7rtr IIIIIIIII IIII t rrrr r IIIIIIIII Dense to very dense, moist, light brown mottled with oxidation, Illlll- -177-1-7--T -(IIIIIII IIIIIIIII - — 7YTTTTTTT TTTTTi-T — silty SAND, no odor, PID <1 ppm. (Blow counts overstated, pounding on rock) (Glacial Till) S-5 12" ' ' 50/6" IIIIIII IIIIIIIII IIII Boring completed at about 21 feet. 11 1 1 11 1 l l I l l l l l l l l l l Perched groundwater encountered at about 15 1/2 feet bgs IIIIIIIII IIIIIII. ATD. ..IIIIIII Groundwater measured at 16.25 feet below TOC on 9/14/17. 11-f IIIIIII fi- � t t ttTfi IIIIIIIII tt t-t-r Illlii Groundwater measured at 16.61 feet below TOC on 10/2/17. Ecology Well ID: BIZ 383 777Y-TTTTT TTTTTTT- SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm) I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content 3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit Grout/Concrete Natural Water Content ® Screened Casing Mar-Vel Marble TESTING KEY n Blank Casing 202 Main St. GSA = Grain Size Analysis VGroundwater level at Edmonds, WA time of drilling (ATD) or 200W = 200 Wash Analysis_ on date of Date: October 2017 Project No.: 1811.22 Consol. = Consolidation Test measurement. Zipper Geo Associates BORING B-5/MW-5 Att. = Atterberq Limits 19019 36th Ave. W, Suite E LOG: Lynnwood, WA Page 1 of 1 Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 6-inch Top Elevation: 39.17 feet Drilling Method: HSA Hammer Type: Auto B-6/MW-6 Date Drilled: 9/13/2017 Drill Rig: B-61 Truck Logged by_: JST SOIL DESCRIPTION U) PENETRATION RESISTANCE (blows/foot) co ` E J o 0) Standard Penetration Test E The stratification lines represent the approximate boundaries Q Q_ 10 a Q Hammer Weight and Drop: U -�5 a) between soil types. The transition may be gradual. Refer to e 3 -- report text and appendices for additional information. � m (2 0 20 40 60° IIII ',II IIIIIIIII IIII ..- Medium dense, moist, gray to brown mottled with oxidation, r- r Y SAND, with grave, no odor, ppm. (Weathered:- silt gravel, PID <1 IIIIIII IIIIIIIII IIIIIII Glacial Till) S-1 18" gp -1-7-1-777 IIIIIII 77 T T�TTTT IIII IIII TTTTI T - IIIIIII -------------------------------------------- JJJ��J '..IIIIIII '..IIIIIII 1J1111111 IIIIIIIII IIIIIIIII 1LLLLLLs IIIIIII (IIIIIII Very dense, damp, gray,sand SILT, some ravel, no odor, Y g PID <1 ppm. (Glacial Till) S-2 18" 68 I I I I I I I -�--4-i-4-+ I I I I I I I I I -++-+++++++ I I I I I I I +++ + - '......Illlll IIIIIIIII IIII Very dense, moist, gray, silt SAND, with gravel, no odor, PID T S-3 12° <1 ppm. (Glacial Till) 11 4 4++ - �_ _ 55 '....IIIIIII IIIIIII IIII '..IIIIIII IIIIIIIII IIII '. 11 �t -+1tItt.t.tt tt.tt- , '......... IIIIIIIII IIII Very dense, wet, light brown, silty SAND, interbedded with T gray, SAND with silt, some gravel, no odor, PID <1 ppm. S-a 11 18" 60 (Glacial Till) ..IIIIIII IIIIIIIII IIII Very dense, wet, gray to brown, SAND, with silt and gravel, interbedded with silty SAND, no odor, PID <1 ppm. (Glacial Till) Very dense, wet, blue to gray, sandy SILT, no odor, PID <1 ppm. (Glacial Till) SAMPLE LEGEND GROUNDWATER LEGEND I2-inch O.D. split spoon sample 0 Clean Sand 3-inch I.D. Shelby tube sample ® Bentonite Grout/Concrete ® Screened Casing TESTING KEY n Blank Casing GSA = Grain Size Analysis V Groundwater level at time of drilling (ATD) or 20OW = 200 Wash Analysis �_ on date of Consol. = Consolidation Test measurement. Att. = Atterberq Limits S-5 I 12" S-6 I 11" �D v O %Fines (<0.075 mm) O % Water (Moisture) Content Plastic Limit Liquid Limit Natural Water Content Mar-Vel Marble 202 Main St. Edmonds, WA Date: October 2017 Project No.: 1811.22 Zipper Geo Associates BORING B-6/MW-6 19019 36th Ave. W, Suite E LOG; Lynnwood, WA Page 1 of 2 Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 6-inch Top Elevation: 39.17 feet Drilling Method: HSA Hammer Type: Auto B-6/MW-6 Date Drilled: 9/13/2017 Drill Rig: B-61 Truck Logged by_: JST E a) SOIL DESCRIPTION �� E J n U) � - a 2 (D 0 PENETRATION RESISTANCE (blows/foot) co o U —° m 0) ~ The stratification lines represent the approximate boundaries between soil types. The transition may be gradual. Refer to report text and appendices for additional information. Standard Penetration Test Q Hammer Weight and Drop: 20 40 60 Very dense, saturated, blue to gray, gravelly SILT, with sand, S-7 91, 50/3" no odor, PID <1 ppm. (Glacial Till) rr.I_I_L_L- iiliiiili -1-T-1-1 -T.-1.7 ii1111 77777T7 Very dense, saturated, blue to gray, SILT, with sand, trace s-s I 10 IIIIIII IIIIIII lillllill IIIIIIIII IIIIIIII. IIIIIIIII gravel, no odor, PID <1 ppm. (Glacial Till) �.�I-I I LI-I 1 IIIIIIII _I._IJJ,-41 -1.J,-1 IIIIIIIII 4141-41411 IIIIIII' Dens----- ped, gray, r y-SAND-------g ravel, moderate Dense, saturated, ra ,SAND, trace silt and ravel, moderate odor, PID <1 m. Unusual odor unlike typical hydrocarbon T s9 I 181,:. .. r 1 �I -1 i 1 -t -t rt rt rt t t 7 odor. Smelled sickly sweet and herby) (Glacial Advance Outwash) it33 :;' ' F 77 I -i IIIIIIIII _F -1-7-1-77 IIIIIIIII 7777777- IIIIIII Dense, saturated, gray, SAND, trace silt and ravel, moderate g y g odor, PID <1 ppm. (Same unusual odor as above) (Glacial Advance Outwash) Very dense, saturated, gray, SAND, trace silt and gravel, moderate odor, PID=57.2 ppm. (Same unusual odor as S-10 18" sell 1a" 1 I I ! I -I I I I I I I I I LLLLf-L-! 'IIIIIII I lit 1 L-1 1 _1 I i I I I II -; _ _ ♦ Illlll, i I 46 55 ',: — = . as — .— above) (Glacial Advance Outwash) Very dense, saturated, gray, SAND, trace silt and gravel, no odor, PID <1(GlacialAdvance Outwash ppm. ( Glacial ) S-12 18" rrrl 1 1 1 1 1 1 T7T7 63 — -r :•;: (-I-I-f I-I- -I-1-I-I-f_ Boring completed at about 38 1 /2 feet. 'IIIIIII i i ii i IIII i 1 i Groundwater observed at about 24 1 /2 feet bgs ATD. Groundwater measured at 14.29 feet below TOC on 9/12/17. Groundwater measured at 14.61 feet below TOC on 10/2/17. Ecology Well ID: BIZ 384 iiliiiil t.r r l I-f-I-f 1111 y rt IIIIIIII rt t t ttt.t T iiliiiil 1111 _17-1- _. 1111 11ii1 ii1111 -7777T-T _ ii1111 ii1111 IIIIIIII -1-I.-14 -� -4 4 IIIIIIIII -4 4.4 4 4 4+ 1 IIIIIII' .IIIIIIII IIIIIIIII IIIIIII' IIIIIIII IIIIIIIII IIIIIIII' IIIIIII I_.r l-I I_1_I_I I_ IIIIIIII III _1_I_I7 7 rt.�.7 7 IIIIIIII rtrtrt YrtrtYrtY IIIIIIIII 11 IIIIIII I I I I I I I I I I I I I I I I SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm) I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content 3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit Grout/Concrete Natural Water Content ® Screened Casing Mar-Vel Marble TESTING KEY n Blank Casing 202 Main St. GSA = Grain Size Analysis V Groundwater level at Edmonds, WA time of drilling (ATD) or 200W = 200 Wash Analysis_ on date of Date: October 2017 Project No.: 1811.22 Consol. = Consolidation Test measurement. Zipper Geo Associates BORING Att. = Atterberq Limits B-6/MW-6 19019 36th Ave. W, Suite E LOG; Lynnwood, WA Page 2 of 2 Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 6-inch Top Elevation: 39.08 feet Drilling Method: HSA Hammer Type: Auto 13-7/MW-7 Date Drilled: 9/13/2017 Drill Rig: B-61 Truck Logged by_: JST E a) SOIL DESCRIPTION J'u Q 10 E 0 � - a PENETRATION RESISTANCE (blows/foot) co o U 3 ° m U) °) The stratification lines represent the approximate boundaries between soil types. The transition may be gradual. Refer to report text and appendices for additional information. Standard Penetration Test Q Hammer Weight and Drop: 0 20 40 60 (III ',II IIIIIIIII IIII ..- (IIIIIII i '... IIIIIIIII Illlii —17Y�rt—I—Y rtrtYYTY7TT IIIIIIIII rTTYT r r - :_... (IIIIIII Medium dense, dam mottled gray -brown brown with some P, g Y oxidation, silty SAND, no odor, PID <1 ppm. (Weathered Glacial Till) -------------------------------------------- Dense, damp, gray -brown, silt SAND, no odor, PID <1 m. Y Y pp (Glacial Till) T'IIIIIII S-1 1 18" I S-2 18" 21 45 —1— 7-1— 77 I I I I I I I JJ J��J 7 T TTTTTT ( I I I I I I I 11.111111 t TTTTTTT I I I I I I I LLLLL L L �+ +-+ '.....111 III -++-+++++++ IIIIIIIII +�4 +t - Illl�i '...77rt trtrt '..IIIIIII rttYttTt-tt IIIIIIIII —tt1-1—r , '. (IIIIIII Dense, damp, gray, gravelly SAND, with silt, PID=9.6 ppm. (Slight hydrocarbon odor) (Glacial Till) s-3 18"::= 1 '. ' '..IIIIIII IIIIIIIII (IIIIIII _... 47 '...-17T-7T--T '..IIIIIII '_(IIIIIII I I I I I I I I I T—TTTTTTTT IIIIIIIII IIIIIIIII I I I I I I I I I TTTTTI—T.._� (IIIIIII (IIIIIII ( I I I I I I I ++� '....1111111 -+ ++ ++ IlIlI1i11 ++ 4j Ili — •'•—'• ,..(IIIIIII r-I11�tt�� IIIIIIIII IIIIIIIII tttttt+++ IIIIIIIII Ills t- t__ - , IIII '. (IIIIIII Iilllilll I1i111� Dense, wet, gray, silty SAND, trace gravel, no odor, PID=8.4 ppm. (Glacial Till) T s-4 11 18" ••'.�• — r .IIIIIII ''...IIIIIII IIIIIIIII IIIIIIIII IIIIIII (IIIIIII 35 li�� Iii�iill� Ili1 11 ....IIIIIII .'....IIIIIII (IIIIIII Illlli i IIIIIIIII IIIIIIIII IIII IIII IIII ....- ,•,— — — — ••,IIIIIIIII •:•�:• -7YYrtrtrtY IIIIIIIII ttYYYT7Yr IIII Yrtt-r r •,,�:' IIIIIII ',..IIIIIII —77_1_777 IIIIIIIII IIIIIIIII IIIIIII IIIIIII-, _ 7T7TTTTTT TTTTTTT Very dense, saturated, gray, SAND, with gravel and silt, no odor, PID <1 ppm. (Glacial Till) T S-5 I 12" ,:, o '; ' ' IIIIIII I I I I I I I I I I I I I I I I 50/6" I I I I I I I I I I I Boring completed at about 21 feet b s. (( II II I II II Groundwater observed at about 19 feet bgs ATD. IIIIIIIII IIIIIII Groundwater measured at 14.01 feet below TOC on 9/14/17. ..IIIIIII Groundwater measured at 14.31 feet below TOC on 10/2/17. 11 f IIIIIIIII fifi� t t tttfi IIIIIIIII tt t-t-- Illlii Ecology Well ID: BIZ 385 T11TYT�7 YTTTTTTTT TTTTTTT:- SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm) I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content 3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit Grout/Concrete Natural Water Content ® Screened Casing Mar-Vel Marble TESTING KEY n Blank Casing 202 Main St. GSA = Grain Size Analysis VGroundwater level at Edmonds, WA time of drilling (ATD) or 200W = 200 Wash Analysis_ on date of Date: October 2017 Project No.: 1811.22 Consol. = Consolidation Test measurement. Zipper Geo Associates BORING B-7/MW-7 Att. = Atterberq Limits 19019 36th Ave. W, Suite E LOG: Lynnwood, WA Page 1 of 1 Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 6-inch Top Elevation: 42.62 feet Drilling Method: HSA Hammer Type: Auto B-8/MW-8 Date Drilled: 9/13/2017 Drill Rig: B-61 Truck Logged by_: JST E a) SOIL DESCRIPTION J'u Q 10 E 0 � - a PENETRATION RESISTANCE (blows/foot) co o U 3 ° m U) °) The stratification lines represent the approximate boundaries between soil types. The transition may be gradual. Refer to report text and appendices for additional information. Standard Penetration Test Q Hammer Weight and Drop: 0 20 40 60 (III ',II IIIIIIIII IIII Poor recovery, brown, moist, sandy GRAVEL, with silt, no odor. (Blow counts overstated, pounding on rock) (Based on drilling action and observed cuttings we interpret up to 4 feet of weathered till/weathered till fill in this location) s-1 = 1 ..- so/3 7-�-�-rrt-rrt ..IIIIIII -r-t-r-r-r-r7-rr IIIIIIIII rr-r-rr r r - IIIIIII- -1T-f-1-7-f7 T7TT7TTTT 1 1 1 1 1 1 11 1 TT-rTTTT- 1 1 1 1 1 1 1 -------------------------------------------- IIIIIII 1.1 IIIIIIIII 1LLLLLLs_ IIIIIII No recovery. (Based on drilling action and observed cuttings we interpret a glacial till contact at about 4 feet bgs) S_p I 011 1I + + '....III III ++ t + + IIIIIIIII IIII 37 '..IIIIIII '...-1trt-t-t'rtrt '..IIIIIII IIIIIIIII rttrttttt-tt IIIIIIIII IIII .- Tt..rtr '. IIIIIII Very dense, damp, gray -brown, silty SAND, with gravel, no S-3 = 3 '. '..IIIIIII IIIIIIIII (IIIIIII _... 50/3" '...-177-7777 '..IIIIIII '_(IIIIIII I I I I I I I I I TTTTTTTTT IIIIIIIII IIIIIIIII I I I I I I I I I TTTTTI-T.._� (IIIIIII (IIIIIII ( I I I I I I I — := odor, PID <1 ppm. (Glacial Till) ++ '...1111I11 + ++ -+ IIIIIIIII + + ++ - - (IIIIIII .• — �• — ..(IIIIIII IIIIIIIII IIIIIIIII IIIIIIIII Illl�i IIII '. Very dense, moist to wet, mottled gray and brown with T S-4 I 1 V.•.`_ (IIIIIII IIIIIIIII IIIIIII: 50/5" ''.....111i111 ...111II11 7rt7-T77-r7-r IIIIIIIII IIIIIIIII -r-r-rTTTT� _.. (IIIIIII IIIIIII- — lil�lill 1Ii1 11 .,— oxidation, silty SAND, with gravel, no odor, PID <1 ppm. •'•='� (Glacial Till) : •:'•�':' i l l l l l I I I I I I I I I I I I i i i I I I I I I I I I I I I I I I I I : '••'�f IIIIIIIII 17�rtrtrtrtrt '...IIIIIII IIIIIIIII rtrtrt7rtrtTrtr IIIIIIIII IIII trTt-rr r IIIIIIIIL...... ••.�:: •'., � ''...Illllll IIIIIIIII IIIIIIIII - 1TTTT7T 7T-TTTTT TT TTTTT Very dense, grades to saturated at about 19 feet, mottled gray ,• - IIIIIII III�II�I� I�II�II IIIIIIIII 111111111 _ _ IIIIIIIII IIIIIIIII _AL IIII IIII;,,.. and brown with oxidation , silty SAND, with gravel, no odor, PID <1 ppm. (Glacial Till) S-5 14 86 Boring completed at about 21 1/2 feet. 1 Groundwater observed at about 18.5 feet s bg ATD. Groundwater measured at 17.61 feet below TOC on 9/12/17. illllllll T 11 f IIIIIIIII fits t t t ttfi IIII tt t-t-r Groundwater measured at 18.00 feet below TOC on 10/2/17. Ecology 9 Well Tag ID: BIZ 386 IIIIIIIII IIIIIIIII Illlii TTTTTTTTT TTTTTTT SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm) I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content 3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit Grout/Concrete Natural Water Content ® Screened Casing Mar-Vel Marble TESTING KEY n Blank Casing 202 Main St. GSA = Grain Size Analysis VGroundwater level at Edmonds, WA time of drilling (ATD) or 200W = 200 Wash Analysis_ on date of Date: October 2017 Project No.: 1811.22 Consol. = Consolidation Test measurement. Zipper Geo Associates BORING B-8/MW-8 Att. = Atterberq Limits 19019 36th Ave. W, Suite E LOG: Lynnwood, WA Page 1 of 1 Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 6-inch Top Elevation: 40.82 feet Drilling Method: HSA Hammer Type: Auto 13-9/MW-9 Date Drilled: 9/14/2017 Drill Rig: B-61 Truck Logged by_: JST SOIL DESCRIPTION PENETRATION RESISTANCE (blows/foot) - co J'u Standard Penetration Test o E The stratification lines represent the approximate boundaries Q 10 a Q Hammer Weight and Drop: U U) a) between soil types. The transition may be gradual. Refer to E 0� °) report text and appendices for additional information. � ° m (2 0 20 40 60 IIII ',II IIIIIIIII IIII ..- III11111 i '... IIIIIIIII Illlii -17Y�rt-I-Y '..IIIIIII rtrtYYTY7TT IIIIIIIII rTTYT r r - :_... (IIIIIII Medium dense, moist, gray -brown, silt SAND, some ravel, 9 Y Y g S-1 12" 26 -1_7_1_777 77 7TTTT *1 TTTTTTT - no odor, PID <1 ppm. (Weathered Glacial Till) I I I I I JJJ� �J IIIIIII 11.11111.11 IIIIIIIII -LLLLil L IIIIIII Medium dense, moist, gray -brown, silty SAND, some gravel to about 5 1/2 feet. IIIIIII IIIIIIIII IIIIIII ----------------g y------S-2 Medium dense, moist, gray -brown, SAND, some silt, no odor, 16" t t+ ',.IIIIIII +++++++ +++++ + - 20 PID <1 ppm. (Glacial Outwash) -------------------------------------------- -17rt-trtrtrt IIIIIIIII rtrt.rtttt.t.tt IIII1111.. rt.firr,,., Very dense, moist, gray with oxidation, silty SAND, some gravel (Glacial Till). s-3 1a^ IIIIIII IIIIIIIII IIIIIII 67 177-7T77 IIIIIII 7777TTTTT IIIIIIIII TTTTTTT ` IIIIIII ----------------------------------- - - Very dense, moist, gray, SAND, some silt and gravel, no odor, IIIIIII I I I I I 1 1 IIIIIIIII I I I I I I I I 1 LILL IIIIIII I I I 1 1 1 1 1 PID<1 ppm. Vertical contact at 8 1/2 feet, silty SAND with some oxidation alongcontact. Glacial Outwash ( -----------------------------------------� S-4 1 16" I .•. �-I-I-�-L-i-r -r-F...-+.,.-++�...+� IIIIIIIII +.�+-+-.�.+-F - _.. IIIIIII 73 Very dense, damp to moist, gray, silty SAND, with gravel, no odor, PID <1 ppm. (Glacial Till) :�. .IIIIIII 1-111-"��t 11 1 1 i I 1 1 tlttttttt i I 1 1 1 1 I 1 1 tt+1 I I I 1 Very dense, damp to moist, mottled gray and brown, silty S-5 I 12^ — 111I11 I111I11 II111� _.. 50/6" ''.....IIIiI11 ''..IIIIIII 7rt7Y77T7T IIIIIIIII IIIIIiI11 TT? 7-1 T77 (IIIIIII IIIIIII ; GRAVEL, with sand, no odor. (Glacial Till) 11 • •.�•. a a a G L L;= - :'IIIIIIIII — 'IIIIIIIII -i-++-4-4 IIIIIIIII +++++++++ IIIIIIIII IIII +++a-_ IIII ....- �� •••':'........,..IIIIIII IIIIIIIII 17-1-t-tYrtY IIIIIIIII tYYYY t7t-r IIIIIIIII IIII Yrrr r r " IIIIIII I�f7 -ITITTTITTI (TITIIITIIII� — •_p.:'; '......IIIIII� '......IIIII IIIIIIIII Very dense, saturated, gray -brown, SAND, with silt, some .' �:'. —' — :�... gravel, no odor, PID <1 ppm. (Glacial Till) s-s I 16° - -- IIIIIIIII -� - IIIIIIIII IIII 75 IIIIIIIII IIIIIIIII Illlii ''....IIIIIII IIIIIIIII (IIIIIII -111-t-t-t-t _t_t t t t t_I____ tt r r r boring completed at about ee gs. Groundwater observed at about 18 1/2 feet bgs ATD. Groundwater measured at 14.73 feet below TOC on 9/14/17. Groundwater measured at 15.99 feet below TOC on 10/2/17. 1T11T�T�7 777YTTTTT TTTTTTT_._.. 26 Ecology Well ID: BIZ 387 SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm) I2-inch O.D. split spoon sample 0 Clean Sand O % Water (Moisture) Content 3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit Grout/Concrete Natural Water Content ® Screened Casing Mar-Vel Marble TESTING KEY n Blank Casing 202 Main St. GSA = Grain Size Analysis VGroundwater level at Edmonds, WA time of drilling (ATD) or 200W = 200 Wash Analysis _ on date of Date: October, 2017 Project No.: 1811.22 Consol. = Consolidation Test measurement. BORING Zipper Geo Associates B-9/MW-9 Att. = Atterberq Limits 19019 36th Ave. W, Suite E LOG: Lynnwood, WA Page 1 of 1 ZIPPER GEO ASSOCIATES, LLC 19019 36`h Avenue West, Suitc E, Lynnwood, Washington 98036 Test Pit Log TP-1A Project: Mar-Vel Marble Location: See Site and Exploration Plan, Figure 1 Project No: 1811.22 Approx. Ground Surface Elevation: 38 feet Date Excavated: 08/21/2017 Depth Material Description Sample PID Odor (ft) (ppm) Loose, damp, dark brown, SAND, with silt and organics 1 (SANDY TOPSOIL) ....................................... Medium dense, damp, brown, SAND, with silt and gravel, some organics, oxidation mottling from 1 to 3 feet bgs 2 (WEATHERED GLACIAL TILL) 221 Slight 3 ........................................ Very dense, moist, light brown, sandy SILT, with gravel 4 (Glacial Till) Some perched groundwater in sand lens at 4 5 feet bgs. Transitions to gray at 4 feet and below. Color change coincides with moderate odor of TPH. 6 Discoloration and odor most distinct in north sidewall. Moderate to strong odor of TPH from approximately 4 to 10 feet bgs in north sidewall. 7 TP-1A @7' 1647 Strong 8 9 TP-1A, S-Side @10' 7.1 Mod. 10 Odor decreases to slight below 10 feet bgs in north sidewall. 11 12 7.2 Slight to 13 Odor decreases to trace below 13 feet bgs in north none 14 sidewall. 15 Field indications of PCS extend to the south of the north sidewall for approximately 10 feet in a zone between 6 16 and 10 feet bgs. Test pit completed at about 18 feet bgs. 17 slight to 18 Perched groundwater observed at about 4 feet bgs. 13 none ZIPPER GEO ASSOCIATES, LLC 19019 36`h Avenue West, Suitc E, Lynnwood, Washington 98036 Test Pit Log TP-1113 Location: See Site and Exploration Plan, Figure 1 Approx. Ground Surface Elevation: 38 feet Project: Mar-Vel Marble Project No: 1811.22 Date Excavated: 08/21/2017 Depth (ft) Material Description Sample PID (ppm) Odor 1 Loose, damp, dark brown, SAND, with silt and organics (SANDY TOPSOIL) ....................................... Medium dense, damp, brown, SAND, with silt and gravel, some organics, oxidation mottling from 1 to 3 feet bgs (WEATHERED GLACIAL TILL) ........................................ Very dense, moist, light brown, sandy SILT, with gravel (Glacial Till). Some perched groundwater in sand lens at 4 feet bgs. Transitions to gray at 4 feet and below. Color change coincides with moderate odor of TPH. Discoloration and odor most distinct in north sidewall. Moderate to strong odor of TPH from approximately 4 to 10 feet bgs. Field indications of PCS extend approximately 15 feet from west sidewall of excavation at a depth of approximately 4 to 10 feet bgs. 2 3 4 5 6 7 8 9 10 TP-113, E-Side @10' 1.7 slight to none 11 12 Test pit completed at about 12 feet bgs. Perched groundwater observed at about 4 feet bgs. 13 14 15 16 17 18 ZIPPER GEO ASSOCIATES, LLC 19019 36`h Avenue West, Suitc E, Lynnwood, Washington 98036 Test Pit Log TP-2A Project: Mar-Vel Marble Location: See Site and Exploration Plan, Figure 1 Project No: 1811.22 Approx. Ground Surface Elevation: 40 feet Date Excavated: 08/21/2017 Depth Material Description Sample PID Odor (ft) (ppm) Loose, damp, dark brown, gravelly SAND, with silt and 1 organics (SANDY TOPSOIL)* ....................................... Medium dense, damp, light brown, gravelly SILT, with sand (WEATHERED GLACIAL TILL)* < 1 None 2 < 1 None ...................................... 1.1 None 3 Very dense, damp, light brown, gravelly SILT, with sand (GLACIAL TILL)* 4 Gray discoloration and odor from 4 % to 9 % feet bgs 43.3 Moderate 5 along edges of heating oil UST cavity and directly below the UST cavity. Field indications of TPH extended 6 approximately 10 to 15 feet beyond the edges of the UST cavity to the east and west at a depth of approximately 5 TP-2A, E-Side@7' < 1 7 to 8 feet bgs. TP-2A, W-Side@7' 1.1 TP-2A@8' 8 Very dense, damp, light brown, sandy GRAVEL, with silt (GLACIAL TILL) 232.7 Strong 9 TP-2A@10' 27.6 Moderate 10 1.9 Slight 11 12 Test pit completed at about 10 % feet bgs. No groundwater observed during excavation. 13 * TP-2A transected the north edge of heating oil UST cavity. We observed pea gravel backfill in the central 14 approximately 8 feet of the southern edge of the test pit to a depth of approximately 5 % feet. 15 16 17 18 ZIPPER GEO ASSOCIATES, LLC 19019 36`h Avenue West, Suitc E, Lynnwood, Washington 98036 Test Pit Log TP-2113 Project: Mar-Vel Marble Location: See Site and Exploration Plan, Figure 1 Project No: 1811.22 Approx. Ground Surface Elevation: 40 feet Date Excavated: 08/21/2017 Depth Material Description Sample PID Odor (ft) (ppm) Loose, damp, dark brown, gravelly SAND, with silt and 1 organics (SANDY TOPSOIL)* ........................................ Medium dense, damp, light brown, gravelly SILT, with sand (WEATHERED GLACIAL TILL)* None 2 None ...................................... None 3 Very dense, damp, light brown, gravelly SILT, with sand (GLACIAL TILL)* Moderate 4 Gray discoloration and odor from 4 % to 9 % feet bgs 5 along edges of heating oil UST cavity and directly below the UST cavity. Field indications of TPH extended 6 approximately 10 to 15 feet beyond the edges of the UST cavity to the north and south at a depth of approximately 7 5 to 8 feet bgs. Moderate Tp-2B, S-Side@8' 2.2 (South) 8 Very dense, damp, light brown, sandy GRAVEL, with silt TP-2B, N-Side@8' < 1 (North) (GLACIAL TILL) Moderate 9 10 11 12 Test pit excavation completed at about 10 % feet bgs. No groundwater observed during excavation. 13 * TP-213 transected the heating oil UST cavity. We observed pea gravel backfill in the central approximately 14 8 feet of the test pit to a depth of approximately 5 % feet. 15 16 17 18 ZIPPER GEO ASSOCIATES, LLC 19019 36`h Avenue West, Suitc E, Lynnwood, Washington 98036 Test Pit Log TP-3 Location: See Site and Exploration Plan, Figure 1 Approx. Ground Surface Elevation: 38 feet Project: Mar-Vel Marble Project No: 1811.22 Date Excavated: 08/21/2017 Depth (ft) Material Description Sample PID (ppm) Odor 1 Loose, damp, brown, silty SAND, with organics (SANDY TOPSOIL) . ....................................... Dense, damp, light brown with oxidation mottling, silty SAND, with gravel (WEATHERED GLACIAL TILL) 2 3 4 1.2 Test pit excavation completed to about 3 % feet bgs. No field indications of PCS. No groundwater observed during excavation. 5 6 7 8 9 10 11 12 13 14 15 16 17 18 ZIPPER GEO ASSOCIATES, LLC 19019 36`h Avenue West, Suitc E, Lynnwood, Washington 98036 Test Pit Log TP-4 Project: Mar-Vel Marble Location: See Site and Exploration Plan, Figure 1 Project No: 1811.22 Approx. Ground Surface Elevation: 43 feet Date Excavated: 08/21/2017 Depth Material Description Sample PID Odor (ft) (ppm) Medium dense, damp, light brown, silty SAND, with 1 gravel, some oxidation mottling (WEATHERED GLACIAL TILL) None ...................................... Slight 2 Very dense, damp, light brown, silty SAND, with gravel (GLACIAL TILL) 3 Localized pea gravel from approximately 1 to 6 feet bgs. 4 Field indications of PCS from approximately 2 to 7 feet bgs Moderate 5 and radially approximately 3 to 5 feet from the edges of the hoist cavity. Gray discoloration and a slight to 6 moderate odor. TP-4, E-Side@6.5' 28.8 TP-4@7' Moderate 7 TP-4, N-Side@7' 2.2 Slight to 8 Light brown, damp, very dense, sandy GRAVEL, with silt TP-4, W-Side@8' none 9 10 (GLACIAL TILL) 11 12 13 14 15 16 Test pit completed at about 16 % feet bgs. 17 Backfilled with clean soil below 8 feet. Backfilled with PCS above 8 feet. 18 Groundwater not observed during excavation. APPENDIX B LABORATORY TESTING PROCEDURES AND RESULTS LABORATORY TESTING PROCEDURES A series of laboratory tests were performed during the course of this study to evaluate the index and geotechnical engineering properties of the subsurface soils. Descriptions of the types of tests performed are given below. Visual Classification Samples recovered from the exploration locations were visually classified in the field during the exploration program. Representative portions of the samples were carefully packaged in moisture tight containers and transported to our laboratory where the field classifications were verified or modified as required. Visual classification was generally done in accordance with ASTM D-2488. Visual soil classification includes evaluation of color, relative moisture content, soil type based upon grain size, and accessory soil types included in the sample. Soil classifications are presented on the exploration logs in Appendix A. Photoionization Detector Recovered soil samples were also screened in the field shortly after collection with a hand held Photoionization Detector (PID) to evaluate the presence or absence of Volatile Organic Compounds (VOCs). PID readings are presented on the exploration logs in Appendix A in parts per million (ppm). Moisture Content Determinations Moisture content determinations were performed on representative samples obtained from the explorations in order to aid in identification and correlation of soil types. The determinations were made in general accordance with the test procedures described in ASTM D-2216. Moisture contents are presented on the exploration logs in Appendix A. Grain Size Analysis A grain size analysis indicates the range in diameter of soil particles included in a particular sample. Grain size analyses were performed on representative samples in general accordance with ASTM: D-422. The results of the grain size determinations for the samples were used in classification of the soils, and are presented in this appendix. GRAIN SIZE ANALYSIS Test Results Summary ASTM D 422 100 90 = 80 W ?� 70 m IW 60 W Z 50 Z W tU W 40 W a 30 20 10 0 1000.000 100.000 10.000 1.000 0.100 0.010 0.001 PARTICLE SIZE IN MILLIMETERS Coarse Fine Coarse Medium Fine Silt Clay BOULDERS COBBLES GRAVEL SAND FINE GRAINED Comments: Exploration Sample Depth (feet) Moisture (%) Fines (%) Description B-1 S-3 7.5 11.5 40.3 Silty SAND some gravel Project No.: 1798.01 PROJECT NAME: Zipper Geo Associates, LLC Geotechnical and Environmental Consultants DATE OF TESTING: 5/1/2017 Graphite Studios GRAIN SIZE ANALYSIS Test Results Summary ASTM D 422 100 90 = 80 W ?� 70 m IW 60 W Z 50 Z W tU W 40 W a 30 20 10 0 1000.000 100.000 10.000 1.000 0.100 0.010 0.001 PARTICLE SIZE IN MILLIMETERS Coarse Fine Coarse Medium Fine Silt Clay BOULDERS COBBLES GRAVEL SAND FINE GRAINED Comments: Exploration Sample Depth (feet) Moisture (%) Fines (%) Description B-1 S-5 15 11.8 46.6 Silty SAND some gravel Project No.: 1798.01 PROJECT NAME: Zipper Geo Associates, LLC Geotechnical and Environmental Consultants DATE OF TESTING: 5/1/2017 Graphite Studios GRAIN SIZE ANALYSIS Test Results Summary ASTM D 422 100 90 = 80 W ?� 70 m 60 LU Z 50 Z W tU IW 40 W a 30 20 10 0 1000.000 100.000 10.000 1.000 0.100 0.010 0.001 PARTICLE SIZE IN MILLIMETERS BOULDERS COBBLES Coarse Fine Coarse Medium Fine Silt Clay GRAVEL SAND FINE GRAINED Comments: Exploration Sample Depth (feet) Moisture (%) Fines (%) Description B-1 S 8 30 21.0 5.3 SAND, some silt, trace gravel Project No.: 1798.01 PROJECT NAME: Zipper Geo Associates, LLC Geotechnical and Environmental Consultants DATE OF TESTING: 5/1/2017 Graphite Studios GRAIN SIZE ANALYSIS Test Results Summary ASTM D 422 100 90 = 80 W ?� 70 m 60 LU Z 50 Z W tU IW 40 W a 30 20 10 0 1000.000 100.000 10.000 1.000 0.100 0.010 0.001 PARTICLE SIZE IN MILLIMETERS BOULDERS COBBLES Coarse Fine Coarse Medium Fine Silt Clay GRAVEL SAND FINE GRAINED Comments: Exploration Sample Depth (feet) Moisture (%) Fines (%) Description B-2 S-6 20 9.6 25.4 SAND with silt and gravel Project No.: 1798.01 PROJECT NAME: Zipper Geo Associates, LLC Geotechnical and Environmental Consultants DATE OF TESTING: 5/20/2017 Graphite Studios USDA United States Department of Agriculture N RCS Natural Resources Conservation Service A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for Snohomish County Area, Washington Graphite Art Studios November 14, 2017 3 546340 470 49 42" N 0 Custom Soil Resource Report Soil Map 546350 546360 546370 5463W r � SJil Ma n • 47' 48' 4U' N 546340 546350 546360 546370 5463M 3 Map Scale: 1:433 i printed on A portrait (8.5" x 11") sheet. Meters N 0 5 10 20 30 Feet 0 20 40 80 120 Map projection: Web Mercator Comer coordinates: WGS84 Edge tics: UTM Zone 1ON WGS84 3 546390 546400 • 47° 48' 42" N ti • � u i�i 47° 48' 4U' N 546400 3 MAP LEGEND Area of Interest (AOI) Area of Interest (AOI) Soils 0 Soil Map Unit Polygons rwr Soil Map Unit Lines Soil Map Unit Points Special Point Features Uo Blowout ® Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp + Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot d Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip oa Sodic Spot Custom Soil Resource Report MAP INFORMATION Spoil Area The soil surveys that comprise your AOI were mapped at 1:24,000. 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 Other misunderstanding of the detail of mapping and accuracy of soil .- Special Line Features line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed Water Features scale. Streams and Canals Transportation Please rely on the bar scale on each map sheet for map 1 1 F Rails measurements. Interstate Highways Source of Map: Natural Resources Conservation Service r.x US Routes Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Major Roads Local Roads Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts Background distance and area. A projection that preserves area, such as the Aerial Photography Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Snohomish County Area, Washington Survey Area Data: Version 16, Oct 30, 2017 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jul 7, 2014—Jul 8, 2014 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. Custom Soil Resource Report Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 5 Alderwood-Urban land complex, 2 to 8 percent slopes Totals for Area of Interest 0.4 0.4 100.0% 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. Custom Soil Resource Report An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha -Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha -Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. Custom Soil Resource Report Snohomish County Area, Washington 5—Alderwood-Urban land complex, 2 to 8 percent slopes Map Unit Setting National map unit symbol: 2hz9 Elevation: 50 to 800 feet Mean annual precipitation: 25 to 60 inches Mean annual air temperature: 48 to 52 degrees F Frost -free period: 180 to 220 days Farmland classification: Not prime farmland Map Unit Composition Alderwood and similar soils: 60 percent Urban land: 25 percent Minor components: 6 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Alderwood Setting Landform: Till plains Parent material: Basal till Typical profile H1 - 0 to 7 inches: gravelly ashy sandy loam H2 - 7 to 35 inches: very gravelly ashy sandy loam H3 - 35 to 60 inches: gravelly sandy loam Properties and qualities Slope: 2 to 8 percent Depth to restrictive feature: 20 to 40 inches to densic material Natural drainage class: Moderately well drained Capacity of the most limiting layer to transmit water (Ksat): Very low to moderately low (0.00 to 0.06 in/hr) Depth to water table: About 18 to 36 inches Frequency of flooding: None Frequency of ponding: None Available water storage in profile: Low (about 3.0 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 4s Hydrologic Soil Group: B Other vegetative classification: Limited Depth Soils (G002XN302WA) Hydric soil rating: No Minor Components Mckenna Percent of map unit: 2 percent Landform: Depressions Hydric soil rating: Yes Norma Percent of map unit: 2 percent Custom Soil Resource Report Landform: Depressions Hydric soil rating: Yes Terric medisaprists Percent of map unit: 2 percent Landform: Depressions Hydric soil rating: Yes Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section VI, Page 1 Section VI — Other Permits Section VI Summary: Narrative Other permits are not anticipated to be required for this project besides those from the City of Edmonds. C � 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section VII, Page 1 Section VII — Bond Quantities, Declaration of Covenant, & Operation and Maintenance Manual Section VII Summary: Narrative The Bond Quantity Worksheet is a standalone document that can also be submitted to the City of Edmonds separately from this document. A Declaration of Covenant is provided for the on -site BMPs proposed. The Operation and Maintenance Manual is a standalone document that will be given to the owner following the construction of the project. Narrative The maintenance manual contained herein is for the Graphite Art Studios building project. The contractor will be responsible for the maintenance and operation of all stormwater structures and BMPs requiring maintenance during construction and, after construction, responsibility will pass to the building owner. The project contractor will be responsible for passing along the information in this maintenance manual to the owner. Upon request by the City, it shall be made available for their inspection. It is generally expected that few to none of these defects will be present upon the yearly inspection of each facility. C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Site Improvement Bond Quantity Worksheet S15 Web date: 04/03/2015 LIM King County Department of Permitting & Environmental Review 35030 SE Douglas Street, Suite 210 Snoqualmie, Washington 98065-9266 206-296-6600 TTY Relay 711 Project Name: Graphite Art Studios Location: 202 Main Street, Edmonds, WA 98020 Clearing greater than or equal to 5,000 board feet of timber? yes If yes, Forest Practice Permit Number: (RCW 76.09) Page 1 of 9 Graphite SI Bond Quantity X no For alternate formats, call 206-296-6600. Date: 12/24/2019 Project No.: Activity No.: 19144.20 Note: All prices include labor, equipment, materials, overhead and profit. Prices are from RS Means data adjusted for the Seattle area or from local sources if not included in the RS Means database. Unit prices updated: 3/2/2015 Version: 3/2/2015 Report Date: 12/24/2019 Site Improvement Bond Quantity Worksheet S15 Web date: 04/03/2015 Reference # Unit Price Unit Quantity # of Applications Cost EROSION/SEDIMENT CONTROL Number Backfill & compaction -embankment ESC-1 $ 6.00 CY $ - Check dams, 4" minus rock ESC-2 SWDM 5.4.6.3 $ 80.00 Each $ - Crushed surfacing 1 1/4" minus ESC-3 WSDOT 9-03.9(3) $ 95.00 CY $ - Ditching ESC-4 $ 9.00 CY $ - Excavation -bulk ESC-5 $ 2.00 CY $ - Fence, silt ESC-6 SWDM 5.4.3.1 $ 1.50 LF 230 1 $ 345.00 Fence, Temporary (NGPE) ESC-7 $ 1.50 LF $ - Hydroseeding ESC-8 SWDM 5.4.2.4 $ 0.80 SY $ - Jute Mesh ESC-9 SWDM 5.4.2.2 $ 3.50 SY $ - Mulch, by hand, straw, 3" deep ESC-10 SWDM 5.4.2.1 $ 2.50 SY $ - Mulch, by machine, straw, 2" deep ESC-11 SWDM 5.4.2.1 $ 2.00 SY $ - Piping, temporary, CPP, 6" ESC-12 $ 12.00 LF $ - Piping, temporary, CPP, 8" ESC-13 $ 14.00 LF $ - Piping, temporary, CPP, 12" ESC-14 $ 18.00 LF $ - Plastic covering, 6mm thick, sandbagged ESC-15 SWDM 5.4.2.3 $ 4.00 SY $ - Rip Rap, machine placed; slopes ESC-16 WSDOT 9-13.1(2) $ 45.00 CY $ - Rock Construction Entrance, 50'x15'x1' ESC-17 SWDM 5.4.4.1 $ 1,800.00 Each 1 1 $ 1,800.00 Rock Construction Entrance, 100'x15'x1' ESC-18 SWDM 5.4.4.1 $ 3,200.00 Each $ - Sediment pond riser assembly ESC-19 SWDM 5.4.5.2 $ 2,200.00 Each $ - Sediment trap, 5' high berm ESC-20 SWDM 5.4.5.1 $ 19.00 LF $ - Sed. trap, 5' high, riprapped spillway berm section ESC-21 SWDM 5.4.5.1 $ 70.00 LF $ - Seeding, by hand Sodding, 1" deep, level ground ESC-22 SWDM 5.4.2.4 $ 1.00 SY $ - ESC-23 SWDM 5.4.2.5 $ 8.00 SY $ - Sodding, 1" deep, sloped ground ESC-24 SWDM 5.4.2.5 $ 10.00 SY $ - TESC Supervisor ESC-25 $ 110.00 HR 40 1 $ 4,400.00 Water truck, dust control ESC-26 SWDM 5.4.7 $ 140.00 HR $ - WRITE -IN -ITEMS **** (see paqe 91 Filter Socks $ 35.50 Each 15 1 $ 532.50 $ - $ - ESC SUBTOTAL: 30% CONTINGENCY & MOBILIZATION: ESC TOTAL: COLUMN: Page 2 of 9 Graphite SI Bond Quantity $ 7,077.50 $ 2,123.25 $ 9,200.75 A Unit prices updated: 3/2/2015 Version: 3/2/2015 Report Date: 12/24/2019 Site Improvement Bond Quantity Worksheet Web date: 04/03/2015 Existing Right -of -Way Future Public Right of Way & Drainage Facilities Private Improvements Unit Price Unit Quant. Cost Quant. Cost Quant. Cost GENERAL ITEMS No. Backfill & Compaction- embankment GI - 1 $ 6.00 CY $ - $ - 680 $ 4,080.00 Backfill & Compaction- trench GI - 2 $ 9.00 CY $ - $ - $ - Clear/Remove Brush, by hand GI - 3 $ 1.00 SY $ - $ - $ Clearing/Grubbing/Tree Removal GI - 4 $ 10,000.0o Acre $ - $ - $ - Excavation - bulk GI - 5 $ 2.00 CY $ - $ - 170 $ 340.00 Excavation - Trench GI - 6 $ 5.00 CY $ - $ - $ - Fencing, cedar, 6' high GI - 7 $ 20.00 LF $ - $ - $ Fencing, chain link, vinyl coated, 6' high GI - 8 $ 20.00 LF $ - $ - $ Fencing, chain link, gate, vinyl coated, 2 GI - 9 $ 1,400.00 Each $ - $ - $ Fencing, split rail, 3' high GI - 10 $ 15.00 LF $ - $ - $ Fill & compact - common barrow GI - 11 $ 25.00 CY $ - $ - $ Fill & compact - gravel base GI - 12 $ 27.00 CY $ - $ - $ Fill & compact - screened topsoil GI - 13 $ 39.00 CY $ - $ - $ Gabion, 12" deep, stone filled mesh GI - 14 $ 65.00 SY $ - $ - $ Gabion, 18" deep, stone filled mesh GI - 15 $ 90.00 SY $ - $ - $ Gabion, 36" deep, stone filled mesh GI - 16 $ 150.00 SY $ - $ - $ - Grading, fine, by hand GI - 17 $ 2.50 SY $ - $ - 1600 $ 4,000.00 Grading, fine, with grader GI - 18 $ 2.00 SY $ - $ - $ - Monuments, 3' long GI - 19 $ 250.00 Each $ - $ - $ Sensitive Areas Sin GI - 20 $ 7.00 Each $ - $ - $ Sodding, 1" deep, sloped ground GI - 21 $ 8.00 SY $ - $ - $ Surveying, line & grade GI - 22 $ 850.00 Day $ - $ - $ Surveying, lot location/lines GI - 23 $ 1,800.00 Acre $ - $ - $ Traffic control crew 2 flaggers GI - 24 $ 120.00 HR 40 $ 4,800.00 $ - $ Trail, 4" chipped wood GI - 25 $ 8.00 SY $ - $ - $ Trail, 4" crushed cinder GI - 26 $ 9.00 SY $ $ - $ Trail, 4" top course GI - 27 $ 12.00 SY $ $ - $ - Wall, retaining, concrete GI - 28 $ 55.00 SF $ $ - 250 $ 13,750.00 Wall, rockery GI - 29 $ 15.00 SF $ $ $ - Page 3 of 9 SUBTOTAL 4,800.00 22,170.00 Unit prices updated: 03/02/2015 *KCC 27A authorizes only one bond reduction. Version: 03/02/2015 Graphite SI Bond Quantity Report Date: 12/24/2019 Site Improvement Bond Quantity Worksheet Web date: 04/03/2015 Existing Right-of-way Future Public Right of Way & Drainage Facilities Private Improvements Unit Price Unit I Quant. Cost QuantT Cost Quant, F Cost ROADIMPROVEMENT No. AC Grinding, 4' wide machine < 1000s RI - 1 $ 30.00 SY $ - $ - $ AC Grinding, 4' wide machine 1000-2000 RI - 2 $ 16.00 SY $ - $ - $ AC Grinding, 4' wide machine > 2000s RI - 3 $ 10.00 SY $ - $ - $ AC Removal/Disposal RI - 4 $ 35.00 SY $ - $ - $ Barricade, type III Permanent RI - 6 $ 56.00 LF $ - $ - $ Curb & Gutter, rolled RI - 7 $ 17.00 LF $ - $ - $ Curb & Gutter, vertical RI - 8 $ 12.50 LF 307 $ 3,837.50 $ - $ Curb and Gutter, demolition and disposal RI - 9 $ 18.00 LF 307 $ 5,526.00 $ - $ Curb, extruded asphalt RI - 10 $ 5.50 LF $ - $ - $ Curb, extruded concrete RI - 11 $ 7.00 LF $ - $ - $ Sawcut, asphalt, 3" depth RI - 12 $ 1.85 LF 750 $ 1,387.50 $ - $ Sawcut, concrete, per 1" depth RI - 13 $ 3.00 LF $ - $ - $ Sealant, asphalt RI - 14 $ 2.00 LF $ - $ - $ Shoulder, AC, see AC road unit price RI - 15 $ - SY $ - $ - $ Shoulder, gravel, 4" thick RI - 16 $ 15.00 SY $ - $ - $ - Sidewalk, 4" thick RI - 17 $ 38.00 SY 313 $ 11,889.78 $ - 334 $ 12,679.33 Sidewalk, 4" thick, demolition and dispos RI - 18 $ 32.00 SY 313 $ 10,016.00 $ - 67 $ 2,154.67 Sidewalk, 5" thick RI - 19 $ 41.00 SY $ - $ - $ - Sidewalk, 5" thick, demolition and dispos RI - 20 $ 40.00 SY $ - $ - $ Sign, handicap RI - 21 $ 85.00 Each $ - $ - $ Striping, per stall RI - 22 $ 7.00 Each $ - $ - $ Striping, thermoplastic, for crosswalk RI - 23 $ 3.00 1 SF 192 $ 576.00 $ - $ Striping, 4" reflectorized line RI - 24 $ 0.50 1 LF 1 200 $ 100.00 $ - $ Page 4 of 9 SUBTOTAL 33, 332.78 14,834.00 Unit prices updated: 03/02/2015 *KCC 27A authorizes only one bond reduction. Version: 03/02/2015 Graphite SI Bond Quantity Report Date: 12/24/2019 Site Improvement Bond Quantity Worksheet Web date: 04/03/2015 Existing Right-of-way Future Public Right of Way & Drainage Facilities Private Improvements Unit Price Unit Quant. Cost Quant. Cost Quant, Cost ROAD SURFACING No. 4" Rock = 2.5 base & 1.5" top course 9 1/2" Rock= 8" base & 1.5" top course Additional 2.5" Crushed Surfacing RS - 1 $ 3.60 SY $ - $ - $ HMA 1/2" Overlay, 1.5" RS - 2 $ 14.00 SY $ - $ - $ HMA 1/2" Overlay 2" RS - 3 $ 18.00 SY 473 $ 8,514.00 $ - $ HMA Road, 2", 4" rock, First 2500 SY RS - 4 $ 28.00 SY $ - $ - $ HMA Road, 2", 4" rock, Qty. over 2500 S RS - 5 $ 21.00 SY $ - $ - $ HMA Road, 3", 9 1/2" Rock, First 2500 S RS - 6 $ 42.00 SY 195 $ 8,176.00 $ - $ HMA Road, 3", 9 1/2" Rock, Qty Over 25 RS - 7 $ 35.00 SY $ - $ - $ Not Used RS - 8 $ - $ - $ - $ Not Used RS - 9 $ - $ - $ - $ HMA Road, 6" Depth, First 2500 SY RS - 10 $ 33.10 SY $ - $ - $ HMA Road, 6" Depth, Qty. Over 2500 SY RS - 11 $ 30.00 SY $ - $ - $ HMA 3/4" or 1", 4" Depth RS - 12 $ 20.00 SY $ - $ - $ Gravel Road, 4" rock, First 2500 SY RS - 13 $ 15.00 SY $ - $ - $ Gravel Road, 4" rock, Qty. over 2500 SY RS - 14 $ 10.00 SY $ - $ - $ PCC Road (Add Under Write -Ins w/Desi RS - 15 $ - $ - $ Thickened Edge IRS - 17 $ 8.60 LF I $ - $ - $ Page 5 of 9 SUBTOTAL 16,690.00 Unit prices updated: 03/02/2015 *KCC 27A authorizes only one bond reduction. Version: 03/02/2015 Graphite SI Bond Quantity Report Date: 12/24/2019 Site Improvement Bond Quantity Worksheet Web date: 04/03/2015 Existing Right-of-way Future Public Right of Way & Drainage Facilities Private Improvements Unit Price Unit Quant. Cost Quant. I Cost Quant. Cost DRAINAGE (CPP = Corrugated Plastic Pipe, N12 or Equivalent) For Culvert prices, Average of 4' cover was assumed. Assumeperforated PVC is same price as solid pipe. Access Road, R/D $ 21.00 SY $ $ $ Bollards - fixed LD- $ Each $Bollards -removable E240.74 $ .34 Each $ $ $ * CBs include frame and lid $ - $ $ CB Type I D - 4 $ 1,500.00 Each 2 $ 3,000.00 $ $ - CB Type IL D - 5 $ 1,750.00 Each $ - $ $ CB Type II, 48" diameter D - 6 $ 2,300.00 Each 3 $ 6,900.00 $ - $ for additional depth over 4' D - 7 $ 480.00 FT 12 $ 5,760.00 $ - $ CB Type II, 54" diameter D - 8 $ 2,500.00 Each $ - $ - 1 $ 2,500.00 for additional depth over 4' D - 9 $ 495.00 FT $ $ - 5 $ 2,475.00 CB Type II, 60" diameter D - 10 $ 2,800.00 Each $ $ - $ - for additional depth over 4' D - 11 $ 600.00 FT $ $ - $ CB Type II, 72" diameter D - 12 $ 3,600.00 Each $ $ - $ for additional depth over 4' D - 13 $ 850.00 FT $ $ - $ Through -curb Inlet Framework Add D - 14 $ 400.00 Each $ $ - $ Cleanout, PVC, 4" D - 15 $ 150.00 Each $ $ - $ Cleanout, PVC, 6" D - 16 $ 170.00 Each $ $ - $ Cleanout, PVC, 8" D - 17 $ 200.00 Each $ - $ - $ - Culvert, PVC, 4" D - 18 $ 10.00 LF 16 $ 160.00 $ - 525 $ 5,250.00 Culvert, PVC, 6" D - 19 $ 13.00 LF 5 $ 65.00 $ - 528 $ 6,864.00 Culvert, PVC, 8" D - 20 $ 15.00 LF $ - $ - $ - Culvert, PVC, 12" D - 21 $ 23.00 LF 137 $ 3,151.00 $ - $ - Culvert, CMP, 8" D - 22 $ 19.00 LF $ - $ - $ - Culvert, CMP, 12" D - 23 $ 29.00 LF $ $ - $ - Culvert, CMP, 15" D - 24 $ 35.00 LF $ $ - $ - Culvert, CMP, 18" D - 25 $ 41.00 LF $ $ - $ - Culvert, CMP, 24" D - 26 $ 56.00 LF $ $ - $ - Culvert, CMP, 30" D - 27 $ 78.00 LF $ $ - $ - Culvert, CMP, 36" D - 28 $ 130.00 LF $ $ - 3 $ 390.00 Culvert, CMP, 48" D - 29 $ 190.00 LF $ $ - $ - Culvert, CMP, 60" D - 30 $ 270.00 LF $ $ - $ - Culvert, CMP, 72" D - 31 1 $ 350.00 LF $ $ - 27 $ 9,450.00 Page 6 of 9 SUBTOTAL 19,036.00 26,929.00 Unit prices updated: 03/02/2015 *KCC 27A authorizes only one bond reduction. Version: 03/02/2015 Graphite SI Bond Quantity Report Date: 12/24/2019 Site Improvement Bond Quantity Worksheet Web date: 04/03/2015 DRAINAGE CONTINUED Existing Right-of-way Future Public Right of Way & Drainage Facilities Private Improvements No. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Culvert, Concrete, 8" D - 32 $ 25.00 LF $ $ $ Culvert, Concrete, 12" D - 33 $ 36.00 LF $ $ $ Culvert, Concrete, 15" D - 34 $ 42.00 LF $ $ $ Culvert, Concrete, 18" D - 35 $ 48.00 LF $ - $ - $ Culvert, Concrete, 24" D - 36 $ 78.00 LF $ - $ - $ Culvert, Concrete, 30" D - 37 $ 125.00 LF $ - $ - $ Culvert, Concrete, 36" D - 38 $ 150.00 LF $ - $ - $ Culvert, Concrete, 42" D - 39 $ 175.00 LF $ - $ - $ Culvert, Concrete, 48" D - 40 $ 205.00 LF $ - $ - $ Culvert, CPP, 6" D - 41 $ 14.00 LF $ - $ - $ Culvert, CPP, 8" D - 42 $ 16.00 LF $ - $ - $ Culvert, CPP, 12" D - 43 $ 24.00 LF $ - $ - $ Culvert, CPP, 15" D - 44 $ 35.00 LF $ - $ - $ Culvert, CPP, 18" D - 45 $ 41.00 LF $ - $ - $ Culvert, CPP, 24" D - 46 $ 56.00 LF $ - $ - $ Culvert, CPP, 30" D - 47 $ 78.00 LF $ - $ - $ Culvert, CPP, 36" D - 48 $ 130.00 LF $ - $ - $ Ditching D - 49 $ 9.50 CY $ - $ - $ Flow Dispersal Trench 1,436 base+ D - 50 $ 28.00 LF $ - $ - $ French Drain 3' depth D - 51 $ 26.00 LF $ - $ - $ Geotextile, laid in trench, polypropylene D - 52 $ 3.00 SY $ - $ - $ Mid -tank Access Riser, 48" dia, 6' deep D - 54 $ 2,000.00 Each $ - $ - $ Pond Overflow Spillway D - 55 $ 16.00 SY $ - $ - $ Restrictor/Oil Separator, 12" D - 56 $ 1,150.00 Each $ - $ - $ Restrictor/Oil Separator, 15" D - 57 $ 1,350.00 Each $ - $ - $ Restrictor/Oil Separator, 18" D - 58 $ 1,700.00 Each $ - $ - $ Riprap, placed D - 59 $ 42.00 CY $ - $ - $ Tank End Reducer 36" diameter D - 60 $ 1,200.00 Each $ - $ - $ Trash Rack, 12" D - 61 $ 350.00 Each $ - $ - $ Trash Rack, 15" D - 62 $ 410.00 Each $ - $ - $ Trash Rack, 18" D - 63 $ 480.00 Each $ - $ - $ Trash Rack, 21" D - 64 $ 550.00 Each $ - $ - $ Page 7 of 9 6-0110]/_1111 Unit prices updated: 03/02/2015 *KCC 27A authorizes only one bond reduction. Version: 03/02/2015 Graphite SI Bond Quantity Report Date: 12/24/2019 Site Improvement Bond Quantity Worksheet Web date: 04/03/2015 Existing Right-of-way Future Public Right of Way & Drainage Facilities Private Improvements Unit Price Unit Quant. Price Quant. I Cost Quant. Cost PARKING LOT SURFACING Not To Be Used For Roads Or Shoulders No. 2" AC, 2" top course rock & 4" borrow PL - 1 $ 21.00 SY NA $ NA $ - $ 2" AC, 1.5" top course & 2.5" base cour i PL-2 $ 28.00 SY NA $ NA $ - $ 4" select borrow PL - 3 $ 5.00 SY NA $ NA $ - $ 1.5" top course rock & 2.5" base course PL-4 $ 14.00 SY NA $ NA $ - $ UTILITY POLES & STREET LIGHTING Utility pole relocation costs must be accompanied b Franchise Utility's Cost Estimate Utility Poles Relocation UP-1 $ 25,000.00 1 Each 1 2 $ 50,000.00 $ - $ - Street Light Poles w/Luminaires UP-2 $ 7,500.00 1 Each $ - $ - $ WRITE -IN -ITEMS Such as detention/water quality vaults. No. Connection to existing Water Main WI-1 $ 2,000.00 Each 2 $ 4,000.00 $ $ Ductile Iron Pipe, 4" Dia. WI-2 $ 50.00 LF $ - $ $ Ductile Iron Pipe, 6" Dia. WI-3 $ 65.00 LF 9 $ 585.00 $ $ - Ductile Iron Pipe, 8" Dia. WI-4 $ 85.00 LF 86 $ 7,310.00 $ $ Gate Valve, 6" Dia. WI-5 $ 250.00 Each 1 $ 250.00 $ $ Gate Valve, 8" Dia. WI-6 $ 380.00 Each 3 $ 1,140.00 $ $ Gate Valve, 12" Dia. WI-7 $ 500.00 Each $ - $ - $ Pressure Reduc. Valve Assembly, 8" Dia. WI-9 $ 3,800.00 Each 1 $ 3,800.00 $ $ Fire Hydrant Assembly WI-8 $ 2,500.00 Each 1 $ 2,500.00 $ $ Sealant Asphalt WI-10 $ 2.00 LF 1400 $ 2,800.00 $ $ Striping, 4" reflectorized line (for parking) WI-11 $ 7.00 Each $ - $ - $ Sternberg Lights WI-12 $ 2,500.00 Each 2 $ 5,000.00 $ $ SUBTOTAL 77,385.00 SUBTOTAL (SUM ALL PAGES): 151,243.78 30% CONTINGENCY & MOBILIZATION: 45,373.13 GRANDTOTAL: 196,616.91 COLUMN: B Page 8 of 9 C 933.00 19,179.90 83,112.90 D Unit prices updated: 03/02/2015 *KCC 27A authorizes only one bond reduction. Version: 03/02/2015 Graphite SI Bond Quantity Report Date: 12/24/2019 Site Improvement Bond Quantity Worksheet Original bond computations prepared by: Name: Taylor Fleming, EIT Date PE Registration Number: Greg Guillen, PE, SE - 25385 Tel. # Firm Name: CG Engineering Address: 250 4th Ave S, Ste 200, Edmonds, WA 98020 Project No Stabilization/Erosion Sediment Control (ESC) Existing Right -of -Way Improvements Future Public Right of Way & Drainage Facilities Private Improvements Calculated Quantity Completed Total Right -of Way and/or Site Restoration Bond*/** (First $7,500 of bond* shall be cash.) Performance Bond* Amount (A+B+C+D) = TOTAL Maintenance/Defect Bond* Total NAME OF PERSON PREPARING BOND* REDUCTION: FINANCIAL GUARANTEE REQUIREMENTS Web date: 04/03/2015 12/24/2019 425.778.8500 19144.20 PERFORMANCE BOND* MINIMUM BOND* AMOUNT PUBLIC ROAD & DRAINAGE AMOUNT REQUIRED FOR RECORDING OR MAINTENANCE/DEFECT BOND* TEMPORARY OCCUPANCY AT (A) $ 9,200.8 SUBSTANTIAL COMPLETION *** (B) $ 196,616.9 (C) $ - (D) $ 83,112.9 (A+B) $ 205,817.7 (T) $ 288,930.6 Minimum is $2000 x 0.30 $ 86,679.2 Minimum is $2000. Date: (B+C)x 0.25 = $ 49,154.2 Minimum is $2000. * NOTE: The word "bond" as used in this document means a financial guarantee acceptable to King County. ** NOTE: KCC 27A authorizes right of way and site restoration bonds to be combined when both are required. The restoration requirement shall include the total cost for all TESC as a minimum, not a maximum. In addition, corrective work, both on- and off -site needs to be included. Quantities shall reflect worse case scenarios not just minimum requirements. For example, if a salmonid stream may be damaged, some estimated costs for restoration needs to be reflected in this amount. The 30% contingency and mobilization costs are computed in this quantity. *"* NOTE: Per KCC 27A, total bond amounts remaining after reduction shall not be less than 30% of the original amount (T) or as revised by major design changes. REQUIRED BOND* AMOUNTS ARE SUBJECT TO REVIEW AND MODIFICATION BY KING COUNTY Page 9 of 9 Unit prices updated: 03/02/2015 Check out the DDES Web site at www.kingcounty._aoy/permits Version: 03/02/2015 Graphite SI Bond Quantity Report Date: 12/24/2019 After recording return to: City Clerk City of Edmonds 121 Fifth Avenue North Edmonds, WA 98020 Document Title(s) Declaration of Covenant - Private Stormwater Facility Reference Number(s) of Related Documents N/A Grantor(s) (Last, First and Middle Initial) Olsen, Mary Grantee(s) (Last, First and Middle Initial) City of Edmonds Legal Description (abbreviated form; i.e., lot, plat or section,. township, range, quarter/quarter) NE 1/4, SE 1/4 SECTION 23, TOWNSHIP 27 NORTH, RANGE 3 EAST, W.M. Assessor's Property Tax Parcel/Account Number at the Time of Recording: 00454800101300 The Auditor/Recorder will rely on the information provided on this form. The staff will not read the document to verify the accuracy or completeness of the indexing information provided herein. DECLARATION OF COVENANT Private Stormwater Facility WHEREAS, the undersigned Declarant(s) have installed a stormwater facility under Edmonds Community Development Code Chapter 18.30 known as a "low impact development best management practices (LID BMP)" in lieu of other required more conventional stormwater systems, as selected below: ❑ Permeable Pavement ❑ Rain Garden / Bioretention Cell ❑ Infiltration Trench ❑ Drywell ❑ Gravelless Chamber © Other Detention Pipe WHEREAS, the City of Edmonds has allowed installation of the LID BMP, subject to the execution and recording of this Declaration of Covenant; NOW, THEREFORE, THE UNDERSIGNED DECLARANT(S), being the owners of the real property ("the Property") located at the following address: 202 Main Street in the City of Edmonds, Washington, and legally described on Exhibit A attached hereto and incorporated herein by this reference as if set forth in full, hereby covenants and agrees, on behalf of himself/herself/themselves/itself and his/her/their/its successors and assigns, as follows: 1. Declarant(s) warrant that he/she/they are the owners of the property described on Exhibit A and have the authority to impose this covenant on the property and bind all future owners, successors, and assigns of the Declarant(s). The Declarant(s), future owners, successors, and assigns of the Declarant(s) shall be referred to collectively as "Owners." 2. The Owners of the property described on Exhibit A agree that the property contains a stormwater management facility called a "LID BMP," which was installed to mitigate the stormwater quantity and quality impacts of some or all of the impervious or non-native pervious surfaces on the property. "Low impact development" means development conducted in a way that seeks to minimize or completely prevent alterations to the natural hydrology of the site. Low impact development includes site planning and design to reduce alterations of natural soil and vegetation cover, minimize impervious surfaces, and specific practices that help to replicate natural hydrology such as permeable pavements, green roofs, soil amendments, bioretention systems, and dispersion of runoff. 3. The Owners of the property described on Exhibit A shall maintain the size, placement, and design of the LID BMP as depicted on the approved site plan, Exhibit B, and design details shall be maintained and may not be changed without written approval either from the Engineering Division of the City of Edmonds or through a future development permit from the City of Edmonds. Chemical fertilizers and pesticides shall not be used where LID BMP is located. . All costs of maintenance and repair shall be the sole responsibility of the Owners. 4. The Owners of the property described on Exhibit A shall inspect LID BMPs annually for physical defects. After major storm events, the system shall also be checked to ensure that the overflow system is working properly. The Owners also shall maintain all LID BMP so it functions as designed on a year-round basis. 5. The City of Edmonds is hereby granted by the Owners the right, but not the obligation, to enter upon the property described on Exhibit A at all reasonable times for the purpose of inspecting the private stormwater LID BMP facility. If, as the result of any such inspection the City of Edmonds determines that the LID BMP is in disrepair, requires maintenance or repair, or is otherwise not functioning as provided in the BMP site plan, the City Engineer or his designee shall have the right, but not the obligation, to order the Owners of the property described on Exhibit A to maintain or repair the same. 6. If the City of Edmonds determines that the LID BMP requires maintenance or repair pursuant to Section 5, the City of Edmonds shall provide notice to the Owners of the deadline within which such maintenance or repair must be completed. Said notice may further advise that, should the violator fail to perform required maintenance or make repairs within the established deadline, the work may be done by the city or a contractor designated by the City Engineer and the expense thereof shall be charged to the Owners. The City's officers, agents, employees, and contractors shall have the right, which is hereby granted by the Owners, to enter upon the property described on Exhibit A in order to perform such work. The Owners shall bear the cost of all work performed. 7. The Owners shall indemnify, defend and hold harmless the City of Edmonds, its officers, officials, employees and agents from any and all claims, demands, suits, penalties, losses, damages, judgments, attorneys' fees and/or costs of any kind whatsoever, arising out of or in any way resulting from the approval of the LID BMP, the installation and presence of the LID BMP, and the acts or omissions of the Owners, their officers, employees, contractors, and agents relating to the construction, operation and maintenance of the LID BMPs on the property, except for the City's intentional and willful tortious acts, and waive and release the City of Edmonds from any and all claims for damages and injunctive relief which the Owners may themselves have now or in the future, by reason of the construction, maintenance and operation of said LID BMPs. 8. This covenant shall run with the land and be binding upon the Declarant(s), as the owner of the property described on Exhibit A, and on Declarant's successors and assigns as to such property. Dated: DECLARANT(S): (Signature) (Print Name) (Signature) (Print Name) State of Washington M1 County of Snohomish APPROVED: CITY OF EDMONDS (Signature) (Print Name) (Title) On this day personally appeared before me { Declarant(s) } to me known to be the individual, or individuals described in and who executed the within and foregoing instrument, and acknowledged that he/she/they signed the same as his/her/their free and voluntary act and deed, for the uses and purposes therein mentioned. SUBSCRIBED AND SWORN before me this day of , 201_. (Signature) (Name legibly printed or stamped) Notary Public in and for the State of Washington. Residing at: My commission expires Exhibit A (PER STATUTORY WARRANTY DEED AFN 201512280304) PARCEL A: LOTS 13, 14, 15 AND 16, BLOCK 1 GEPHART'S 1ST ADDITION TO EDMONDS, ACCORDING TO THE PLAT THEREOF RECORDED IN VOLUME 5 OF PLATS, PAGE 43, RECORDS OF SNOHOMISH COUNTY, WASHINGTON. Exhibit B 60" DIAMETER CORRUGATED ALUMINUM PIPE Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section VII, Page 2 Graphite Art Studios 202 Main Street Edmonds, WA 98020 OPERATION AND MAINTENANCE MANUAL Date: December 2019 C � 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 December 27, 2019 Drainage Report Section VII, Page 3 Operation and Maintenance Manual This Operation and Maintenance Manual has been created for Graphite Art Studios, a 14,599 sf building project on a 0.33 acre lot. The proposed storm system primarily consists of a detention pipe, below the proposed building, that is connected a flow control structure that is located in the parking area on the south side of the building. The detention pipe will collect all on -site runoff (from the building's roof) and convey it to a Type II catch basin before connecting to the public storm main in 2nd Ave S. Included in this Operation and Maintenance Manual is an 11" x 17" Grading and Drainage Plan sheet showing the location of the system. Please note that this map is generated during the design phase and may not reflect all changes made in permitting and construction. CG Engineering may be contacted for an updated copy of this map once the as -built drawings are completed for the site. The contractor will be responsible for the maintenance and operation of all stormwater structures and BMPs requiring maintenance during construction and, after construction, responsibility will pass to the owner. A map of the project area can be seen on the following page in Figure VII-1. Included in this manual are maintenance sheets taken from the 2012 Stormwater Management Manual for Western Washington (as amended in 2014) for the following facilities/activities: Catch Basins: Concrete structures with steel grates that collect stormwater runoff from the site and act as junctions for storm conveyance pipes. Control Structures: Control structures are catch basins or manholes with a restrictor device for controlling outflow from a facility to meet the desired performance. Detention Pipes/Tanks: Detention tanks are underground storage facilities typically constructed with large diameter corrugated pipe. Please note, the detention pipe and control structure are located underneath the roof overhang. For any maintenance activities, extreme caution should be exercised when performing maintenance in the vicinity of the roof overhang. Verify sufficient vehicle and equipment clearances. Vegetation Management: Landscaping can include grading, soil transfer, vegetation removal, pesticide and fertilizer applications, and watering. Stormwater contaminants include toxic organic compounds, heavy metals, oils, total suspended solids, coliform bacteria, fertilizers, and pesticides. Facilities shall be inspected for defects listed in the following facility sheets. Most maintenance tasks are generally reactionary to a defect being found, rather than a matter of constant upkeep. It is generally expected that few to none of these defects will be present upon the yearly inspection of each facility. The facility sheets list the potential conditions warranting maintenance and the expected result following any maintenance. Several engineer's notes for specific tasks are provided within the facility sheets. Unless otherwise noted on the facility sheets the maintenance tasks C 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com Graphite Art Studios - CG #19144.20 December 27, 2019 Drainage Report Section VII, Page 4 should be performed on an "as needed" basis: (a) when the described defect is visible to whomever performs the yearly inspection, or (b) should any defect become apparent between inspections. Figure VII-1. Map of project area (from Edmonds GIS). C 4M 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com NE 1 /4, SE 1 /4 SECTION 23, TOWNSHIP 27 NORTH, RANCE 3 EAST, W.M. C C T-1 \ ��J" PVC=35.38 E P =33660 CB T-1 \ ENGINEERING \ DO SO CB h� IE (SW "� = 5.45 RIM=39-28 SSMH \ 1 E (NW) 6" PVC- 37.83 250 4TH AVE. S., SUITE 200 RIM=38.59 LF- "DI@1�6 5� ` \ EDMONDS, WASHINGTON 98020 IE (S) 8" CCNC=30.94 I Nam„ A PHONE (425) 778-8500 FAX (425) 778-5536 SDMH RIM=38.15 / �' 1 INTERSECTION Rig. \ \ IE (E) 8" PVC=32.65 C3. & PATIO GRADES IE (5) 12" PVC=29.45 IE (N) 12"' PVC=29.30 1 '11,qV RI T44 RIM T.39 -1 7 ST , \ IE (SE) 12" PVC 41.14 IE (NW) 12" Pvc= 39.89 C40.51 q, CB T-1 r / RIM-45.82 IE (SE) 12" Pvc= - IE (NW) 12" Pvc= W 11 I A ROOF �W qqq 40.66 \ LL TOC43.111 \ k/ - 1 OVERHANGS GU OC 36.30 e�� ✓ ENTRY 41.0 II / / a 4'MA%HEIGHT \ ST C WALL PER STR 3 � STRUCi / OC 38.27 /�TQ ENTRY 42.0 ROOF, 43.25 all 1Y �/ 4" AREA DRAIN\ 37.86 f RIM. 41.9(TIE INTO ROOF DRAINS) �P I n - /el ,, / ENTRY 42.0 / A\ v 3' MAX HEIGHT PROPOSED ART STUDIOS BUILDING CONC WALL PER MAIN FFE: 42.0 STRUCT \ 3 SW DRIVEWAY 2 2 NE DRIVEWAY \ 3. GRADES - ` "/ 4' 8" x 4' 8" 3. & PATIO GRADES \ � E / t I94 2 �sy. RISER ROOM / 1-BOX PER PUD \ \ Q 1I 25 �\� ENTRY 37.0 ROOF AND FOOTING T DRAINS ARE 2 m SEPARATE LINES z 4\` PROPOSED CAP DETENTION / dl C W (/ q TANK /FLOW CONTRO �,@ I d v1 aC 3 STRUCTURE I- 1211PROPOSED C w w PVC\ df'w I PROPOSED GRAPHITE PROPOSED o a a 3 ya, I GRAPHITE ARTS APARTMENTS GRAPHITEART BUILDING EDGE BUILDING EDGE / BUILDING EDGE BUILDING EDGE zo.o' R R 16.0' R o, x / REPLACE E%ISl'IING / / w o 2.5' 13.5' 4.0' 4.0' 2.0' 30.0' 2.0' Q N x o x � ROOF GRIND AND 0.25' GRIND AND OVERHANG I OVERLAY I OVERLAY o \ 11 LF- 12' 40. O ° 42.15 I P RSM 10.0% T III - - '30 ( 1.5% / 2.09 `.0% 1.5% 1 - _ - _. DESIGN: TAF IE N 2933 8 " CHANNEL - �, DRAWN: ATD " \ O I ^I CHECK: JPU JOB NO: 19144.20 \ TYPE II INLET DATE: 08/29/19 \ \ \ SS \ CATCH BASIN S GRADING AND DRAINAGE PLAN © 2 EAST SECTION SOUTH ALLEY SECTION 1 SCALB 1"=20' p 0 0 0 q0 scALe 1"=5' GRADING AND DRAINAGE NOTES: 1. AMINI MUM OF 3' HORIZONTAL SEPARATION AND I'VERTICAL SEPARATION IS REQUIRED BETWEEN DRY UTILITIES (POWER, GAS, PHONE, CABLE, ETC) AND SEWER, WATER AND STORM, AND A MINIMUM OF 5' HORIZONTAL SEPARATION AND 1' VERTICAL SEPARATION FROM ANY CITY OWNED LINES. 2. ALL DISTURBED AREAS ON AND OFF -SITE SHALL BE COMPOST AMENDED PER REQUIREMENTS OF BMP T5.13 IN THE STORMWATER MANUAL, VOLUME V, CHAPTER 5. 3. ATYPE II CATCH BASIN IS REQUIRED WHENEVER RIM TO INVERT EXCEEDS 51. 4. TOPAND TOE REFER TO FINISHED GRADE ON SITE WALLS. REFER TO STRUCTURAL DRAWINGS. 5. FOOTING DRAINS ARE ON -SITE, SHOWN SPACED OFF OF THE BUILDING FOR GRAPHICAL PURPOSES. DETAIL 2/C3.2 DEPICTS TYPICAL FOOTING LOCATION. ROOF DRAINS ARE ROUTED THROUGH BUILDING TO DETENTION PIPE BY PLUMBING. FOOTING AND ROOF DRAINS SHALL ALL BE ON PRIVATE PROPERTY. 6. DURING REMOVAL AND REPLACEMENT OF CB#7, VERIFY CONDITION, SIZE, MATERIAL OF EXISTING PIPE TO CB T-1. REPLACE PER CITY STANDARDS IF PIPE IS FAILING. 7. ROOF SHALL BE COATED WITH AN INERT, NON -LEACHABLE ENAMEL COATING. 8. NEW/REPLACED IMPERVIOUS SURFACE (INCLUDING ROW): 17,110SF - NEW BUILDING:14,599 SF ROOF AREA (INCLUDES OVERHANGS). RUNOFF ROUTED TO DETENTION PIPE THROUGH ROOF DRAINS. REPLACED SIDEWALK: 2,223 SF. DETENTION PIPE SIZED TO INCLUDE SIDEWALK AREA EVEN THOUGH RUNOFF WILL FLOW INTO THE GUTTER AND PUBLIC STORM SYSTEM. - REPLACED ASPHALT: 436 SF. DETENTION PIPE SIZED TO INCLUDE ASPHALTAREA EVEN THOUGH RUNOFF WILL FLOW INTO THE GUTTER AND PUBLIC STORM SYSTEM. * SITE CONCRETE DEPICTED IN C3.1 IS INCLUDED AS PART OF ROOF IN DETENTION DESIGN, AS IT IS NEARLY ALL UNDER OVERHANGS. CATCH BASIN SCHEDULE MARK TYPE RIM ELEV INV ELEV NOTES 12" (SW))=2286.6311 UCTURE O46 II 35.96 12(. EXISTING E12 (SE)=29 .61TYPE 12(SE)=28.7 4" IN E)=29.0 O 41" 35'9 12" (SE)=29.0 FOOTING DRAIN LINES IN ROW TYPE II 12"(NW)=28.90 ARE SOLID PIPES 4" (SW) = 32.55 41" 12"(NW)=31.43 O 39.76 IT (SE)=31.53 - TYPE II 12" (S) = 31.53 12" (NW)=33.29 ® 46 41.59 12"(NE)=33.39 POTHOLE SEWER MAIN PRIOR TYPE II 12" (SE)=36.5+ TO CB INSTALLATION FLOW CONTROL 1 O 54" 41.3 12"(SW)=34.5 STRUCTURE C3. TYPE II 36" (NE)=34.5 SOLID LID; 3 NON -SLIPCOVER C3, © TYPEI 37.95 6"(N)=36.0 INSTALL PEDESTRIAN GRATE REPLACE EXISTING CB; (D TYPEI 39.03 8"(W)=37.42 INSTALLAT LOW POINT IN GUTTER FLOW LINE BEFORE BULB -OUT FLOW CONTROL ® 54" 40.2 12"(NW)=33.7 STRUCTURE TYPE II 36" (E) = 33.7 SOLID LID NOTES: 1. CB# 8 WAS DESIGNED FOR THE GRAPHITE APARTMENTS PROJECT TO THE SOUTH, WHICH IS ANTICIPATED TO BE IN CONSTRUCTION CONCURRENTLY WITH GRAPH ITE ART STUDIOS. IT DOES NOT NEED TO BE CONSTRUCTED AS PART OF THIS PROJECT. GRADING QUANTITIES TOTAL EXCAVATION (CUT)- 170 CU YDS TOTAL EMBANKMENT(FILL)- 680 CU YDS TOTAL 850 CU YDS THE QUANTITIES SHOWN ABOVE ARE FOR THE PERMIT PROCESS ONLY. THESE VALUES ARE APPROXIMATE. DO NOT USE FOR BIDDING, PAYMENT, OR ESTIMATING PURPOSES. L7PAVING LEGEND NEW ASPHALT 11 OVERLAY EXISTING ASPHALT NEW CONCRETE APPROVED FOR CONSTRUCTION CITY OF EDMONDS DATE' BY: CITY ENGINEERING DIVISION Z Q J V Q Z Q In O p N Q 0 o') Z F Q Q a N 3 Z L tz Q p :20 cl � Q N m w O p 0 N LJ 0 IEET C3.1 Graphite Art Studios - CG #19144.20 Drainage Report December 27, 2019 Section VII, Page 5 SAMPLE ACTIVITY LOG DATE FACILITY MAINTENANCE PERFORMED RESULTS/ NOTES C 4M 250 4th Avenue South, Suite 200 Edmonds, WA 98020 ENGINEERING ph.425.778.8500 1 f.425.778.5536 www.cgengineering.com No. 3 — Closed Detention Systems (Tanks/Vaults) Maintenance Defect Conditions When Maintenance is Needed Results Expected Component When Maintenance is Performed Storage Area Plugged Air Vents One-half of the cross section of a vent is Vents open and blocked at any point or the vent is damaged. functioning. Debris and Sediment Accumulated sediment depth exceeds 10% All sediment and of the diameter of the storage area for 1/2 debris removed from length of storage vault or any point depth storage area. exceeds 15% of diameter. (Example: 72-inch storage tank would require cleaning when sediment reaches depth of 7 inches for more than 1/2 length of tank.) Joints Between Any openings or voids allowing material to All joint between Tank/Pipe Section be transported into facility. tank/pipe sections (Will require engineering analysis to are sealed. determine structural stability). Tank Pipe Bent Out Any part of tank/pipe is bent out of shape Tank/pipe repaired or of Shape more than 10% of its design shape. (Review replaced to design. required by engineer to determine structural stability). Vault Structure Cracks wider than 1/2-inch and any Vault replaced or Includes Cracks in evidence of soil particles entering the repaired to design Wall, Bottom, structure through the cracks, or specifications and is Damage to Frame maintenance/inspection personnel structurally sound. and/or Top Slab determines that the vault is not structurally sound. Cracks wider than 1/2-inch at the joint of any No cracks more than inlet/outlet pipe or any evidence of soil 1/4-inch wide at the particles entering the vault through the walls. joint of the inlet/outlet pipe. Manhole Cover Not in Place Cover is missing or only partially in place. Manhole is closed. Any open manhole requires maintenance. Locking Mechanism Mechanism cannot be opened by one Mechanism opens Not Working maintenance person with proper tools. Bolts with proper tools. into frame have less than 1/2 inch of thread (may not apply to self-locking lids). Cover Difficult to One maintenance person cannot remove lid Cover can be Remove after applying normal lifting pressure. Intent removed and is to keep cover from sealing off access to reinstalled by one maintenance. maintenance person. Ladder Rungs Unsafe Ladder is unsafe due to missing rungs, Ladder meets design misalignment, not securely attached to standards. Allows structure wall, rust, or cracks. maintenance person safe access. Catch Basins See "Catch Basins" See "Catch Basins" (No. 5). See "Catch Basins" (No. 5) (No. 5). Volume V — Runoff Treatment BMPs — December 2014 4-36 No. 4 - Control Structure/Flow Restrictor Maintenance Defect Condition When Maintenance is Needed Results Expected Component When Maintenance is Performed General Trash and Debris Material exceeds 25% of sump depth or 1 Control structure (Includes Sediment) foot below orifice plate. orifice is not blocked. All trash and debris removed. Structural Damage Structure is not securely attached to Structure securely manhole wall. attached to wall and outlet pipe. Structure is not in upright position (allow up Structure in correct to 10% from plumb). position. Connections to outlet pipe are not watertight Connections to outlet and show signs of rust. pipe are water tight; structure repaired or replaced and works as designed. Any holes --other than designed holes --in the Structure has no structure. holes other than designed holes. Cleanout Gate Damaged or Missing Cleanout gate is not watertight or is missing. Gate is watertight and works as designed. Gate cannot be moved up and down by one Gate moves up and maintenance person. down easily and is watertight. Chain/rod leading to gate is missing or Chain is in place and damaged. works as designed. Gate is rusted over 50% of its surface area. Gate is repaired or replaced to meet design standards. Orifice Plate Damaged or Missing Control device is not working properly due to Plate is in place and missing, out of place, or bent orifice plate. works as designed. Obstructions Any trash, debris, sediment, or vegetation Plate is free of all blocking the plate. obstructions and works as designed. Overflow Pipe Obstructions Any trash or debris blocking (or having the Pipe is free of all potential of blocking) the overflow pipe. obstructions and works as designed. Manhole See "Closed See "Closed Detention Systems" (No. 3). See "Closed Detention Systems" Detention Systems" (No. 3). (No. 3). Catch Basin See "Catch Basins" See "Catch Basins" (No. 5). See "Catch Basins" (No. 5). (No. 5). Volume V — Runoff Treatment BMPs — December 2014 4-37 No. 5 — Catch Basins Maintenance Defect Conditions When Maintenance is Needed Results Expected When Component Maintenance is performed General Trash & Trash or debris which is located immediately No Trash or debris located Debris in front of the catch basin opening or is immediately in front of blocking inletting capacity of the basin by catch basin or on grate more than 10%. opening. Trash or debris (in the basin) that exceeds 60 No trash or debris in the percent of the sump depth as measured from catch basin. the bottom of basin to invert of the lowest pipe into or out of the basin, but in no case less than a minimum of six inches clearance from the debris surface to the invert of the lowest pipe. Trash or debris in any inlet or outlet pipe Inlet and outlet pipes free blocking more than 1/3 of its height. of trash or debris. Dead animals or vegetation that could No dead animals or generate odors that could cause complaints vegetation present within or dangerous gases (e.g., methane). the catch basin. Sediment Sediment (in the basin) that exceeds 60 No sediment in the catch percent of the sump depth as measured from basin the bottom of basin to invert of the lowest pipe into or out of the basin, but in no case less than a minimum of 6 inches clearance from the sediment surface to the invert of the lowest pipe. Structure Top slab has holes larger than 2 square Top slab is free of holes Damage to inches or cracks wider than 1/4 inch and cracks. Frame and/or Top Slab (Intent is to make sure no material is running into basin). Frame not sitting flush on top slab, i.e., Frame is sitting flush on separation of more than 3/4 inch of the frame the riser rings or top slab from the top slab. Frame not securely and firmly attached. attached Fractures or Maintenance person judges that structure is Basin replaced or repaired Cracks in unsound. to design standards. Basin Walls/ Bottom Grout fillet has separated or cracked wider Pipe is regrouted and than 1/2 inch and longer than 1 foot at the secure at basin wall. joint of any inlet/outlet pipe or any evidence of soil particles entering catch basin through cracks. Settlement/ If failure of basin has created a safety, Basin replaced or repaired Misalignment function, or design problem. to design standards. Vegetation Vegetation growing across and blocking more No vegetation blocking than 10% of the basin opening. opening to basin. Vegetation growing in inlet/outlet pipe joints No vegetation or root that is more than six inches tall and less than growth present. six inches apart. Contamination See "Detention Ponds" (No. 1). No pollution present. and Pollution Volume V — Runoff Treatment BMPs — December 2014 4-38 No. 5 — Catch Basins Maintenance Defect Conditions When Maintenance is Needed Results Expected When Component Maintenance is performed Catch Basin Cover Not in Cover is missing or only partially in place. Catch basin cover is Cover Place Any open catch basin requires maintenance. closed Locking Mechanism cannot be opened by one Mechanism opens with Mechanism maintenance person with proper tools. Bolts proper tools. Not Working into frame have less than 1/2 inch of thread. Cover Difficult One maintenance person cannot remove lid Cover can be removed by to Remove after applying normal lifting pressure. one maintenance person. (Intent is keep cover from sealing off access to maintenance.) Ladder Ladder Rungs Ladder is unsafe due to missing rungs, not Ladder meets design Unsafe securely attached to basin wall, standards and allows misalignment, rust, cracks, or sharp edges. maintenance person safe access. Metal Grates Grate opening Grate with opening wider than 7/8 inch. Grate opening meets (If Applicable) Unsafe design standards. Trash and Trash and debris that is blocking more than Grate free of trash and Debris 20% of grate surface inletting capacity. debris. Damaged or Grate missing or broken member(s) of the Grate is in place and Missing. grate. meets design standards. No. 6 �—is Barriers (e.g., Trash Racks) Maintenance fect Condition When Maintenance is Results Expec hen Components Needed Maintena s Performed General Trash and Trash or debris that is plugging more B r cleared to design flow Debris n 20% of the openings in the barrier. apacity. Metal Damaged/ Bars a ent out of shape more n 3 Bars in place with no bends more Missing inches. than 3/4 inch. Bars. Bars are miss�en* er Bars in place according to design. missing. are loose and rust is causing % Barrier replaced or repaired to deterioration to any part of barrier. design standards. Inl utlet Debris barrier missing or not attached to er firmly attached to pipe pe pipe Volume V — Runoff Treatment BMPs — December 2014 4-39 S406 BNK,2 for Streets/ Highways Applicable BMPs: • Select de and anti-icers that cause the least erse environmental i act. Apply only as needed using mi um quantities. • Wher acticable use roadway d ' ers, such as calcium magnesium acetate, p sium acetate, or ilar materials, that cause less adverse environmentaXnDact th rea. and sodium chloride. • Store and transfer nd anti -icing materials on an impervious containment p n acc ance with BMP Storage or Trans fe Outside o olid Raw Ma als By -Products, or Finished Products in this ume. • eep/clean up accumulated de and i-icing materials and grit from roads as soon as possible after the roads ace clears. Recommended Additional BMPs • Intensify roadway cleaning in early spring to help re ve particulates from road surfaces. • Include limits on toxic metals in the specifications for de/anti rs. S407 BMPs for Dust Control at Disturbed Land Areas and Unpaved Roadways and Parking Lots Description of Pollutant Sources: Dust can cause air and water pollution problems particularly at demolition sites and in and areas where reduced rainfall exposes soil particles to transport by air. Pollutant Control Approach: Minimize dust generation and apply environmentally friendly and government approved dust suppressant chemicals, if necessary. Applicable Operational BMPs: • Sprinkle or wet down soil or dust with water as long as it does not result in a wastewater discharge. • Use only local and/or state government approved dust suppressant chemicals such as those listed in Ecology Publication #96-433, Techniques for Dust Prevention and Suppression. • Avoid excessive and repeated applications of dust suppressant chemicals. Time the application of dust suppressants to avoid or minimize their wash -off by rainfall or human activity such as irrigation. • Apply stormwater containment to prevent the conveyance of sediment into storm drains or receiving waters. Volume IV - Source Control BMPs — December 2014 2-15 Ecology prohibits the use of motor oil for dust control. Take care when using lignin derivatives and other high BOD chemicals in areas susceptible to contaminating surface water or ground water. Consult with Ecology and the local permitting authority on discharge permit requirements if the dust suppression process results in a wastewater discharge to the ground, ground water, storm drain, or surface water. Recommended Additional Operational BMPs for Roadways and Other Trafficked Areas: • Consider limiting use of off -road recreational vehicles on dust generating land. • Consider graveling or paving unpaved permanent roads and other trafficked areas at municipal, commercial, and industrial areas. • Consider paving or stabilizing shoulders of paved roads with gravel, vegetation, or local government approved chemicals. • Encourage use of alternate paved routes, if available. • Vacuum sweep fine dirt and skid control materials from paved roads soon after winter weather ends or when needed. • Consider using pre -washed traction sand to reduce dust emissions. Additional Recommended Operational BMPs for Dust Generating Areas: • Prepare a dust control plan. Helpful references include: Control of Open Fugitive Dust Sources (EPA-450/3-88-088), and Fugitive Dust Background Document and Technical Information Document for Best Available Control Measures (EPA-450/2-92-004). • Limit exposure of soil (dust source) as much as feasible. • Stabilize dust -generating soil by growing and maintaining vegetation, mulching, topsoiling, and/or applying stone, sand, or gravel. • Apply windbreaks in the soil such as trees, board fences, tarp curtains, bales of hay, etc. S408 81dlfi for Dust Control at Manufacturing Areas tion of Pollutant Sources: Industrial rial handling activities can genera nsiderable amounts of at is typically removed using exhaust systems. ce nd concrete products and handling powdered materials c s erate dust. Particulate in that can cause air pol include grain u wdust, coal, gravel, crushed rock, ceme d boiler fly ash. Air emissions ca taminate stormwater. The �ective of this BMP is to reduce the stormwater p nts caused by dust generation and control. Volume IV - Source Control BMPs — December 2014 2-16 Applicable Operational BMPs: • Eliminate unpermitted wastewater discharges to s rm sewer, ground water, or surface water. • Convey unpermitted discharges to a sanitary ewer if allowed by the local sewer authority, or to other approve reatment. Obtain appropriate state and local pe ' s for these discharges. Rec mended Additional Operation BMPs: At commercial and indust ' 1 facilities, conduct a survey wastewater discharge connections to storm ins and to surface wate s follows: • Conduct field survey of bu' dings, particularly older buildings, and other indus ' 1 areas to to to storm drains from buildings and paved surfaces. Note here th e join the public storm drain(s). • During non -storm r conditions inspect each storm drain for non- stormwater dischar e Record the locations of all non-stormwater discharges. Incl e all p itted discharges. • If useful, pre re a map of ch area. Show on the map the known location of orm sewers, sam sewers, and permitted and unpermi d discharges. Aerial p tos may be useful. Check records such a iping schematics to identi own side sewer connections and ow these on the map. Consider 'ng smoke, dye, or chemical an ysis tests to detect connections betw two conveyance systems .g., process water and stormwater). If desi ble, conduct TV inspections of the storm drains and record the otage on videotape. Compare the observed locations of connections th the information on the map and revise the map accordingly. Note s ect connections that are inconsistent with the field survey. • Identify all connections to storm sewers or to surface wa and take the actions specified above as applicable BMPs. S411 BMPs for Landscaping and Lawn/ Vegetation Management Description of Pollutant Sources: Landscaping can include grading, soil transfer, vegetation removal, pesticide and fertilizer applications, and watering. Stormwater contaminants include toxic organic compounds, heavy metals, oils, total suspended solids, coliform bacteria, fertilizers, and pesticides. Lawn and vegetation management can include control of objectionable weeds, insects, mold, bacteria, and other pests with pesticides. Examples include weed control on golf course lawns, access roads, and utility corridors and during landscaping; sap stain and insect control on lumber and logs; rooftop moss removal; killing nuisance rodents; fungicide application to patio decks, and residential lawn/plant care. It is possible to Volume IV - Source Control BMPs — December 2014 2-21 release toxic pesticides such as pentachlorophenol, carbamates, and organometallics to the environment by leaching and dripping from treated parts, container leaks, product misuse, and outside storage of pesticide contaminated materials and equipment. Poor management of the vegetation and poor application of pesticides or fertilizers can cause appreciable stormwater contamination. Pollutant Control Approach: Control of fertilizer and pesticide applications, soil erosion, and site debris to prevent contamination of stormwater. Develop and implement an Integrated Pest Management Plan (IPM) and use pesticides only as a last resort. Carefully apply pesticides/ herbicides, in accordance with label instructions. Maintain appropriate vegetation, with proper fertilizer application where practicable, to control erosion and the discharge of stormwater pollutants. Where practicable grow plant species appropriate for the site, or adjust the soil properties of the subject site to grow desired plant species. Applicable Operational BMPs for Landscaping: • Install engineered soil/landscape systems to improve the infiltration and regulation of stormwater in landscaped areas. Do not dispose of collected vegetation into waterways or storm sewer systems. Recommended Additional Operational BMPs for Landscaping: • Conduct mulch -mowing whenever practicable • Dispose of grass clippings, leaves, sticks, or other collected vegetation, by composting, if feasible. • Use mulch or other erosion control measures on soils exposed for more than one week during the dry season or two days during the rainy season. • Store and maintain appropriate oil and chemical spill cleanup materials in readily accessible locations when using oil or other chemicals. Ensure that employees are familiar with proper spill cleanup procedures. • Till fertilizers into the soil rather than dumping or broadcasting onto the surface. Determine the proper fertilizer application rate for the types of soil and vegetation encountered. • Till a topsoil mix or composted organic material into the soil to create a well -mixed transition layer that encourages deeper root systems and drought -resistant plants. • Use manual and/or mechanical methods of vegetation removal rather than applying herbicides, where practical. Volume IV - Source Control BMPs — December 2014 2-22 Applicable Operational BMPs for the Use of Pesticides: • Develop and implement an IPM (See section on IPM in ,4pplicable e Operational BMPs for Vegetation Manyg ment) and use pesticides only as a last resort. • Implement a pesticide -use plan and include at a minimum: a list of selected pesticides and their specific uses; brands, formulations, application methods and quantities to be used; equipment use and maintenance procedures; safety, storage, and disposal methods; and monitoring, record keeping, and public notice procedures. All procedures shall conform to the requirements of Chapter 17.21 RCW and Chapter 16-228 WAC (Appendix IV-D R.7). • Choose the least toxic pesticide available that is capable of reducing the infestation to acceptable levels. The pesticide should readily degrade in the environment and/or have properties that strongly bind it to the soil. Conduct any pest control activity at the life stage when the pest is most vulnerable. For example, if it is necessary to use a Bacillus thuringiens application to control tent caterpillars, apply it to the material before the caterpillars cocoon or it will be ineffective. Any method used should be site -specific and not used wholesale over a wide area. • Apply the pesticide according to label directions. Do not apply pesticides in quantities that exceed manufacturer's instructions. • Mix the pesticides and clean the application equipment in an area where accidental spills will not enter surface or ground waters, and will not contaminate the soil. • Store pesticides in enclosed areas or in covered impervious containment. Do not discharge pesticide contaminated stormwater or spills/leaks of pesticides to storm sewers. Do not hose down the paved areas to a storm sewer or conveyance ditch. Store and maintain appropriate spill cleanup materials in a location known to all near the storage area. • Clean up any spilled pesticides. Keep pesticide contaminated waste materials in designated covered and contained areas. • The pesticide application equipment must be capable of immediate shutoff in the event of an emergency. • Spraying pesticides within 100 feet of open waters including wetlands, ponds, and rivers, streams, creeks, sloughs and any drainage ditch or channel that leads to open water may have additional regulatory requirements beyond just following the pesticide product label. Additional requirements may include: • Obtaining a discharge permit from Ecology. • Obtaining a permit from the local jurisdiction. • Using an aquatic labeled pesticide. Volume IV - Source Control BMPs — December 2014 2-23 obtain a publication entitled "Suspended, Canceled, and Restricted Pesticides " which lists all restricted pesticides and the specific uses that are allowed. Applicable Operational BMPs for Vegetation Management: Use at least an eight -inch "topsoil" layer with at least 8 percent organic matter to provide a sufficient vegetation -growing medium. Amending existing landscapes and turf systems by increasing the percent organic matter and depth of topsoil can substantially improve the permeability of the soil, the disease and drought resistance of the vegetation, and reduce fertilizer demand. This reduces the demand for fertilizers, herbicides, and pesticides. Organic matter is the least water-soluble form of nutrients that can be added to the soil. Composted organic matter generally releases only between 2 and 10 percent of its total nitrogen annually, and this release corresponds closely to the plant growth cycle. Return natural plant debris and mulch to the soil, to continue recycling nutrients indefinitely. Select the appropriate turfgrass mixture for the climate and soil type. Certain tall fescues and rye grasses resist insect attack because the symbiotic endophytic fungi found naturally in their tissues repel or kill common leaf and stem -eating lawn insects. However, they do not, repel root -feeding lawn pests such as Crane Fly larvae, and are toxic to ruminants such as cattle and sheep. The fungus causes no known adverse effects to the host plant or to humans. Endophytic grasses are commercially available; use them in areas such as parks or golf courses where grazing does not occur. Local agricultural or gardening resources such as Washington State University Extension office can offer advice on which types of grass are best suited to the area and soil type. • Use the following seeding and planting BMPs, or equivalent BMPs to obtain information on grass mixtures, temporary and permanent seeding procedures, maintenance of a recently planted area, and fertilizer application rates: Temporary and Permanent Seeding, Mulching, Plastic Covering, and Sodding as described in Volume II. Adjusting the soil properties of the subject site can assist in selection of desired plant species. For example, design a constructed wetland to resist the invasion of reed canary grass by layering specific strata of organic matters (e.g., composted forest product residuals) and creating a mildly acidic pH and carbon -rich soil medium. Consult a soil restoration specialist for site -specific conditions. • Aerate lawns regularly in areas of heavy use where the soil tends to become compacted. Conduct aeration while the grasses in the lawn are growing most vigorously. Remove layers of thatch greater than 3/4-inch deep. Volume IV - Source Control BMPs — December 2014 2-25 Mowing is a stress -creating activity for turfgrass. Grass decreases its productivity when mown too short and there is less growth of roots and rhizomes. The turf becomes less tolerant of environmental stresses, more disease prone and more reliant on outside means such as pesticides, fertilizers, and irrigation to remain healthy. Set the mowing height at the highest acceptable level and mow at times and intervals designed to minimize stress on the turf. Generally mowing only 1/3 of the grass blade height will prevent stressing the turf. Irrigation: The depth from which a plant normally extracts water depends on the rooting depth of the plant. Appropriately irrigated lawn grasses normally root in the top 6 to 12 inches of soil; lawns irrigated on a daily basis often root only in the top 1 inch of soil. Improper irrigation can encourage pest problems, leach nutrients, and make a lawn completely dependent on artificial watering. The amount of water applied depends on the normal rooting depth of the turfgrass species used, the available water holding capacity of the soil, and the efficiency of the irrigation system. Consult with the local water utility, Conservation District, or Cooperative Extension office to help determine optimum irrigation practices. Fertilizer Management: Turfgrass is most responsive to nitrogen fertilization, followed by potassium and phosphorus. Fertilization needs vary by site depending on plant, soil, and climatic conditions. Evaluation of soil nutrient levels through regular testing ensures the best possible efficiency and economy of fertilization. For details on soils testing, contact the local Conservation District, a soils testing professional, or a Washington State University Extension office. Apply fertilizers in amounts appropriate for the target vegetation and at the time of year that minimizes losses to surface and ground waters. Do not fertilize when the soil is dry. Alternatively, do not apply fertilizers within three days prior to predicted rainfall. The longer the period between fertilizer application and either rainfall or irrigation, the less fertilizer runoff occurs. Use slow release fertilizers such as methylene urea, IDBU, or resin coated fertilizers when appropriate, generally in the spring. Use of slow release fertilizers is especially important in areas with sandy or gravelly soils. Time the fertilizer application to periods of maximum plant uptake. Ecology generally recommends application in the fall and spring, although Washington State University turf specialists recommend four fertilizer applications per year. Volume IV - Source Control BMPs — December 2014 2-26 Treatment BMPs: Install biofiltra les 1'f�r strips — (See Chapter 9, Volume V) to Ltreat roadnecessarytWonaintain re • cticable and use engineered topsoils adequa tation. These systems can improve infiltration and stormwater pollutant con eam of roadside ditches. S417 BMPs for Maintenance of Stormwater Drainage and Treatment Systems Description of Pollutant Sources: Facilities include roadside catch basins on arterials and within residential areas, conveyance systems, detention facilities such as ponds and vaults, oil/water separators, biofilters, settling basins, infiltration systems, and all other types of stormwater treatment systems presented in Volume V. Oil and grease, hydrocarbons, debris, heavy metals, sediments and contaminated water are found in catch basins, oil and water separators, settling basins, etc. Pollutant Control Approach: Provide maintenance and cleaning of debris, sediments, and oil from stormwater collection, conveyance, and treatment systems to obtain proper operation. Applicable Operational BMPs: Maintain stormwater treatment facilities per the operations and maintenance (O&M) procedures presented in Section 4.6 of Volume V in addition to the following BMPs: • Inspect and clean treatment BMPs, conveyance systems, and catch basins as needed, and determine necessary O&M improvements. • Promptly repair any deterioration threatening the structural integrity of stormwater facilities. These include replacement of clean -out gates, catch basin lids, and rock in emergency spillways. • Ensure adequacy of storm sewer capacities and prevent heavy sediment discharges to the sewer system. • Regularly remove debris and sludge from BMPs used for peak -rate control, treatment, etc. and discharge to a sanitary sewer if approved by the sewer authority, or truck to an appropriate local or state government approved disposal site. • Clean catch basins when the depth of deposits reaches 60 percent of the sump depth as measured from the bottom of basin to the invert of the lowest pipe into or out of the basin. However, in no case should there be less than six inches clearance from the debris surface to the invert of the lowest pipe. Some catch basins (for example, WSDOT Type 1 L basins) may have as little as 12 inches sediment storage below the invert. These catch basins need frequent inspection and cleaning to prevent scouring. Where these catch basins are part of a stormwater collection and treatment system, the system Volume IV - Source Control BMPs — December 2014 2-37 owner/operator may choose to concentrate maintenance efforts on downstream control devices as part of a systems approach. • Clean woody debris in a catch basin as frequently as needed to ensure proper operation of the catchbasin. • Post warning signs; "Dump No Waste - Drains to Ground Water," "Streams," "Lakes," or emboss on or adjacent to all storm drain inlets where possible. • Disposal of sediments and liquids from the catch basins must comply with "Recommendations for Management of Street Wastes" described in Appendix IV-G of this volume. Additional Applicable BMPs: Select additional applicable BMPs from this chapter depending on the pollutant sources and activities conducted at the facility. Those BMPs include: • S425 BMPs for Soil Erosion and Sediment Control at Industrial Sites • S427 BMPs for Storage of Liquid, Food Waste, or Dangerous Waste C"nntninPrc • S406 BMPs for Spills of Oil and Hazardous Substances • S410 BMPs for Illicit Connections to Storm Drains • S430 BMPs for Urban Streets BMPs for Manufacturing Activities - Outside Description of Pollutant Sources: Manufacturing pollu t sources include outside process areas, stack emissions, and agers where manufacturing activity has taken place in the past d significant exposed llutant materials remain. Poll n Control Approach: Cover an ontain outside manufacturing and prey stormwater run-on and c amination, where feasible. Applicable • Sweep paved stormwater. • Alter the al BMP• re arly, as needed, to prevent contamination of by elimiil<ng or minimizing the contamination of • Ap able Structural Source Co of BMPs: Enclose the activity e Figure 2.2.6): If possible, enclose fhQmanufacturing activity in a • Cover the activity and connect floor drains to a shQQary sewer, if approved by the local sewer authority. Berm or slopNke floor as needed to prevent drainage of pollutants to outside areas. i ure 2.2.7) Volume IV - Source Control BMPs — December 2014 2-38 Disc ar ation S stem PD a e uirements, Ecology, March 2011,webd�ance c .wa. ov/biblio/94146.html. Apply the B gui scr 1 recycling facilities depending on the pollutant sources existing at those ac S424 BMPs for Roof/ Building Drains at Manufacturing and Commercial Buildings Description of Pollutant Sources: Stormwater runoff from roofs and sides of manufacturing and commercial buildings can be sources of pollutants caused by leaching of roofing materials, building vents, and other air emission sources. Research has identified vapors and entrained liquid and solid droplets/particles as potential pollutants in roof/building runoff. Metals, solvents, acidic/alkaline pH, BOD, and organics, are some of the pollutant constituents identified. Ecology has performed a study on zinc in industrial stormwater. The study is presented in Ecology Publication 08-10-025 Suggested Practices to reduce Zinc Concentrations in Industrial Stormwater Discharges, website: htlp://www.ecy.wa.gov/biblio/0810025.html. The user should refer to this document for more details on addressing zinc in stormwater. Pollutant Control Approach: Evaluate the potential sources of stormwater pollutants and apply source control BMPs where feasible. Applicable Operational Source Control BMPs: • If leachates and/or emissions from buildings are suspected sources of stormwater pollutants, then sample and analyze the stormwater draining from the building. • Sweep the area routinely to remove any zinc residuals. If a roof/building stormwater pollutant source is identified, implement appropriate source control measures such as air pollution control equipment, selection of materials, operational changes, material recycle, process changes, etc. Applicable Structural Source Control BMPs: Paint/coat the galvanized surfaces as described in Ecology Publication # 09-10-025_ Applicable Treatment BMPs: Treat runoff from roofs to the appropriate level. The facility may use enhanced treatment BMPs as described in Volume V of the SWMMWW. Some facilities regulated by the Industrial Stormwater General Permit, or local jurisdiction, may have requirements than cannot be achieved with enhanced treatment BMPs. In these cases, additional treatment measures may be required. A treatment method for meeting stringent requirements such as Chitosan-Enhanced Sand Filtration may be appropriate. Volume IV - Source Control BMPs — December 2014 2-46