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161129 MAD (Hydrogeologic Report).pdfHydrogeologic Report New Madrona K-8 Project 9300 236th Street SW Edmonds, Washington November 29, 2016 Submitted To: Ms. Taine Wilton Edmonds School District #15 20420 68th Avenue West Lynnwood, Washington 98036 By: Shannon & Wilson, Inc. 400 N 34th Street, Suite 100 Seattle, Washington 98103 21-1-22082-003 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 i TABLE OF CONTENTS Page 1.0 INTRODUCTION ..................................................................................................................1 2.0 SITE DESCRIPTION ............................................................................................................2 2.1 Site Topography .........................................................................................................2 2.2 Site Drainage and Wetlands .......................................................................................2 3.0 GEOLOGIC CONDITIONS ..................................................................................................2 3.1 Regional Geology and Hydrology ..............................................................................2 3.2 Local Geology and Hydrogeology .............................................................................4 4.0 SUBSURFACE EXPLORATION AND TESTING ..............................................................6 4.1 Drilling and Testing Program .....................................................................................6 4.2 Findings ......................................................................................................................7 4.2.1 Observed Geologic Conditions ....................................................................7 4.2.2 Groundwater Levels and Monitoring ...........................................................8 4.2.3 Aquifer Hydraulic Properties .......................................................................9 4.2.4 Groundwater Quality .................................................................................10 4.2.5 Pilot-scale Injection Well Testing ..............................................................10 4.2.6 Full-scale Injection Well Testing ...............................................................10 5.0 GROUNDWATER MODELING OF PLANNED INJECTION WELLFIELD ..................11 5.1 Overview ..................................................................................................................11 5.2 Conceptual Site Model (CSM) .................................................................................11 5.3 Model Development and Calibration .......................................................................12 5.4 Model Simulation (Base Case) .................................................................................12 5.5 Sensitivity Analysis ..................................................................................................13 6.0 STORMWATER QUALITY DISCUSSION .......................................................................13 7.0 CONCLUSIONS AND RECOMMENDATIONS ...............................................................14 7.1 Injection Well Recommendations ............................................................................14 7.1.1 General .......................................................................................................14 7.1.2 Well Design Recommendations .................................................................15 7.1.3 Injection Well Materials ............................................................................17 7.2 Additional Recommendations ..................................................................................19 8.0 LIMITATIONS ....................................................................................................................20 9.0 REFERENCES .....................................................................................................................22 TABLE OF CONTENTS (cont.) 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 ii FIGURES 1 Vicinity Map 2 Site and Exploration Plan 3 Surficial Geologic Map 4 Deer Creek Water Supply Protection Area Map 5 Generalized Subsurface Profile A-A’ 6 Generalized Subsurface Profile B-B’ 7 Inflow Test Results at Pilot UIC Well IW-1 8 Inflow Test Results at UIC Well IW-2 9 Conceptual UIC Well Design 10 Proposed UIC Well Array Map APPENDICES A Subsurface Explorations B Geotechnical Laboratory Testing C Hydrogeologic Data and Analyses D Groundwater Modeling E Important Information About Your Geotechnical/Environmental Report 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 1 HYDROGEOLOGIC REPORT NEW MADRONA K-8 PROJECT 9300 236TH STREET SW EDMONDS, WASHINGTON 1.0 INTRODUCTION The Edmonds School District No. 15 (the District) contracted Shannon & Wilson, Inc. (Shannon & Wilson) to conduct a preliminary hydrogeologic analysis for the new Madrona K-8 Project (the project), located in Edmonds, Washington (Figure 1). The project is located within the NE ¼ of the SE ¼ of Section 36, Township 27 N, Range 4 E, Willamette Meridian, at 9300-236th Street SW (Snohomish County tax parcel 27033600404600). The District plans to construct the new Madrona K-8 School on the east portion of the approximately 40-acre property. New stormwater management facilities will be required for approximately 13 acres of the site. The purpose of this study was to evaluate the feasibility of using dry wells (or underground injection control [UIC] wells) for project stormwater flow control. Our scope of services, presented in our proposals to the District dated March 16, 2016, August 15, 2016, and September 27, 2016, included:  Observation well drilling, installation, and development at two location (designated OW-1 and OW-2);  Observation well sampling and field hydraulic conductivity (slug) testing (well OW-1);  Observation well groundwater level monitoring (wells OW-1 and OW-2);  Pilot and full-scale UIC well drilling, installation, and inflow testing (designated as UIC wells IW-1 and IW-2, respectively);  Laboratory testing of selected soil samples for grain size analysis and moisture content;  Groundwater modeling to evaluate the proposed UIC well spacing and layout, groundwater mounding, and seepage potential for the nearby ravine slope;  Meetings with the District; and  Preparation of this report, which includes the results of our subsurface explorations, field and laboratory testing, and hydrogeologic analyses. Our scope of services was authorized by the District’s Purchase Order No. 2001500281, dated March 25, 2016; Purchase Order No. 2001500440, dated August 23, 2016; and Purchase Order No. 2001600097, dated October 12, 2016. 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 2 2.0 SITE DESCRIPTION 2.1 Site Topography The approximately 40-acre property includes two steeply sloped wooded areas aligned north to south; one is a ravine located along the eastern property boundary, and the other is a forested incline located near the middle of the property (Figure 2). The existing Madrona Elementary School is located in the northeast corner of the property, and the former Woodway Elementary School is located in the opposite southwest corner of the property. We understand that the planned new construction will occupy the east half of the property, where the existing grade elevation is currently approximately 445 to 455 feet. The project’s elevation datum is referenced to the North American Vertical Datum of 1988 (NAVD88). In addition to school buildings and parking lots, the property currently includes a running track, a baseball field, and soccer fields. The areas surrounding the property consist primarily of residential developments. 2.2 Site Drainage and Wetlands A series of catch basin grates exist along the inside of the track. The project survey performed by Penhallegon Associates Consulting Engineers, Inc. (PACE) shows that these storm drains, along with storm drainage from the existing Madrona Elementary School, discharge to the top of the steep wooded slope in the middle of the property. The survey also identified storm drain discharges to the top of the wooded ravine located on the eastern property boundary. As indicated in Figure 2, three wetland areas were identified in our recent Wetland and Stream Delineation Report (Shannon & Wilson, 2016a). Wetlands A and C are on the wooded slope in the middle of the property and are downgradient from the track storm drain discharges. Seepage emerges within these wetlands, which were delineated between about elevations 410 and 398 feet on this slope. We concluded in our wetland report that these wetlands are supported predominantly by groundwater seeps. Wetland B, which is within the wooded ravine located on the eastern property boundary, is located downgradient of the storm drain outlets associated with the existing Madrona Elementary School and the play fields. We concluded that Wetland B is likely supported by surface flow from the surrounding ravine, the storm drain inputs from the school, and a seasonally high groundwater table. 3.0 GEOLOGIC CONDITIONS 3.1 Regional Geology and Hydrology The project site is located in the Puget Lowland, an elongated topographic and structural depression filled with a sequence of glacial and nonglacial sediments that unconformably overlie 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 3 bedrock. The area has been glaciated seven or more times in the past 2.4 million years. During the last glacial advance, known as the Vashon stade, the ice was greater than 3,000 feet thick in the project area. The Vashon ice sheet receded from the area about 16,500 years ago, leaving topography characterized by low-rolling relief about 500 feet above sea level, with some deeply cut ravines and broad valleys. Since then, present-day geologic processes, such as erosion and deposition by streams, landslides, and human activities, have modified the ground surface. The primary geologic units of significance for the project in the area are summarized as follows:  Vashon Ablation Till (Qvat). Ablation till soils were deposited by one of several depositional processes that take place along the margins of glacial ice and have variable characteristics. Qvat is commonly composed of stratified or irregular bodies, including a heterogeneous mixture of loose to dense gravel, sand, silt, and clay. Qvat may contain scattered cobbles and boulders. Qvat is commonly reworked or modified through sediment slumping or stream action after initial deposition. Seasonally perched groundwater is common near the base of this unit.  Vashon Lodgement Till (Qvt). Vashon lodgement till soils were deposited at the base of an advancing glacial ice sheet and were subsequently overridden by the ice. Qvt is typically a nonsorted diamict consisting of very dense, silty sand with gravel and silty gravel with sand; fines are typically nonplastic to low-plasticity. Qvt has a consistency and strength similar to very soft rock. Qvt may contain interbeds, dikes, and lenses of cohesionless silt, sand, and gravel, as well as cohesive clay and silt. This unit can also contain fractures, and cobbles and boulders are common. Perched groundwater may be encountered within this unit.  Vashon Till-Like Deposits (Qvd). Vashon till-like deposits are nonsorted to poorly sorted diamicts and are intermediate between glacial till and glacial outwash. These sediments may have been reworked by subglacial streams flowing in channels beneath the ice. Qvd soils have a similar grain size distribution to Qvt (although generally lower fines content), but are generally more variable in composition. Perched groundwater may occur within this unit.  Vashon Advance Outwash Deposits (Qva). Vashon advanced outwash consists of glaciofluvial sediment deposited as the glacial ice advanced through the Puget Lowland. Deposits of Qva consist of dense to very dense, poorly graded sand to well-graded sand to silty sand, with varying amounts of gravel and scattered cobbles. Saturated Qva deposits form a productive regional aquifer, and the formation is known to heave when encountered during drilling. Layers of relatively coarse sand within the unsaturated Qva tend to cave during drilling. Where layers of low- permeability soil exist, localized perched groundwater may occur in the Qva above the regional aquifer.  Transitional Bed Deposits (Qtb). Transitional bed deposits are transitional between Vashon glacial and pre-Vashon nonglacial deposits. They are typically fine-grained, 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 4 consisting mostly of thick or thin beds and laminae of clay, silt, and fine sand (Minard, 1983). The major surface water features in project area are Echo Lake and Lake Ballinger (approximately 4,700 southeast and 6,000 feet east of the project, respectively), and Deer Creek, about 5,500 feet northwest of the project. 3.2 Local Geology and Hydrogeology The following summarizes the local surficial and subsurface geology based on published reports, databases, and previous studies:  According to a published geologic map (Minard, 1983; Figure 3) and our previous 22 project test pits and 11 shallow soil borings (Shannon & Wilson, 2016b), the project site is underlain at a shallow depth by glacial till. The top of the till was identified by our previous test pits and shallow borings as starting at between ground surface and 10 feet deep.  The transition from glacial lodgement till (Qvt) to glacial advance outwash (Qva) occurs at approximately elevation 380 to 400 feet on the steep wooded slope in the middle of the property (Minard, 1983).  Boring logs for the nearby Brightwater Project (CDM, 2006) and other nearby wells indicate that the Qva is laterally extensive in the area.  Based on Brightwater Project borings MW-4 and E-106 (drilled about 1,500 feet south of the project site along 244th Street SW), transitional bed (Qtb) deposits underlie the Qva soils locally at about elevation 201 feet (CDM, 2006). The following summarizes the local groundwater conditions based on published reports, online databases, and previous studies:  The online Washington State Department of Ecology (Ecology) water resources and well log databases (Ecology, 2016a and 2016b) identify multiple irrigation and domestic wells in southwest Edmonds vicinity that are completed in the Qva aquifer. With one possible exception, none of these wells appears to be within ¼-mile of the portion of the site undergoing redevelopment. No municipal water supply wells are reported to be within ¼-mile of the site. We identified one domestic use groundwater right that has been registered for a well in the vicinity of Firdale Village (Ecology, 2016a). The well’s location was not specified on the water right documentation, but the owner’s address (9619 - 242nd Place SW, Edmonds) is within ¼-mile of the site, cross-groundwater gradient to the project (Figure 4). 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 5  The top of the Qva aquifer occurs between elevations 288 and 278 feet in the vicinity of Brightwater Project exploratory boring MW-4, in the Firdale Village area (CDM, 2006).  The groundwater level in the Qva aquifer is at approximately elevation 259 to 261 feet in City of Edmonds observation well A-2, located approximately 4,500 feet west of the project site (Shannon & Wilson, 2013).  Prior to our current site work, we estimated the hydraulic gradient in the Qva aquifer in the southwest Edmonds area to be to the west at about 0.008 foot per foot (foot/foot). The expected annual groundwater level fluctuation in the Qva aquifer is between about 2 and 5 feet (Shannon & Wilson, 2013; CDM, 2006).  The project site straddles the mapped ten-year time-of-travel zone for a Class A municipal water supply protection area (Figure 4; PACE, 2002). This water source consists of a spring that produces water from the basal Qva aquifer in the Deer Creek ravine. Olympic View Water and Sewer District (Olympic View) owns the Deer Creek water supply and treatment facility. Figure 4 indicates that the hydraulic gradient for the Qva aquifer is approximately west/northwest in the project vicinity. Thomas and others (1997) rated the Qva aquifer in the Project site and most of the vicinity of southwest Edmonds as having a low sensitivity to contamination, based on aquifer characteristics. However, the Deer Creek water supply protection plan states that the Washington State Department of Health assigned the Deer Creek source a high susceptibility rating and established a testing program. The Deer Creek source susceptibility analysis included a review of both geologic and land use factors (PACE 2002). We understand from Robinson Noble, Inc. (Robinson Noble), Olympic View’s hydrogeologic consultant, that the Deer Creek source testing is currently performed after the supply has been treated. Robinson Noble also stated that Deer Creek has multiple monitoring wells located upgradient of the spring source, which are currently not being sampled.  From our conversations with Olympic View and Robinson Noble, we understand that Olympic View recently drilled a test well at 8605-228th Street SW and that they are in the process of developing a new water supply well in this vicinity (Figure 4). The test well was reportedly drilled to about 700 feet deep, and it is located about 3,300 feet northeast of the project site. As of the date of this report, its log was not yet available on the online Ecology well log viewer. Mr. Max Wills of Robinson Noble stated that the intake zone was revised (made more shallow) after the test well’s initial construction and testing. He said that the well is now screened within the Qva aquifer. Olympic View personnel said it may soon be supplemented by a second new well. Olympic View personnel stated that they are not currently using this or other wells in the project vicinity. We suggested to Olympic View, via Robinson Noble, the advantage of working together with them to obtain concurrent Qva aquifer water level measurements at the test well and the Madrona K-8 Qva wells. These measurements could assist in better defining the local Qva gradient. As of the date of this report, we have not received a response from Olympic View. 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 6 4.0 SUBSURFACE EXPLORATION AND TESTING 4.1 Drilling and Testing Program Our drilling and testing program consisted of the following:  Subcontracted Holt Services, Inc. to drill three borings, including installation of two observation wells and one pilot dry well. These were drilled using the sonic core drilling method: ― Observation well OW-1, drilled to 185.5 feet below ground surface (bgs); screened 175.4 to 185 feet bgs. ― Pilot dry well IW-1, drilled to 91.2 feet bgs; screened 63.3 to 90.4 feet bgs. IW-1 is located approximately 25 feet east of OW-1. ― Observation well OW-2, drilled to 190 feet bgs; screened 179.2 to 183.9 feet bgs; vibrating wire piezometers (VWPs) at 66.3 feet (VWP1) and 146.3 feet (VWP2).  Subcontracted Malcolm Drilling Company, Inc. to complete one full-scale dry well, using the auger drill method: ― Full-scale dry well, IW-2, drilled to 120.4 feet bgs; screen exposed to formation from about 62 to 119.7 feet bgs. IW-2 is located approximately 14 feet northwest of OW-2.  Observed construction of observation wells OW-1 and OW-2 and pilot dry well IW-1. Construction details for the wells and VWPs are presented in the boring logs and in Tables A-1 and A-2 in Appendix A.  Observed construction of full-scale dry well IW-2. Well construction details are presented in the boring log and in Table A-1 in Appendix A.  Logged and photographed the sonic core soil samples and logged the auger cuttings. Collected sub-samples for laboratory geotechnical analysis.  Estimated the approximate well locations and reference elevations based on field measurements.  Developed observation wells OW-1 and OW-2 using an inertial-style pump (Waterra) equipped with a combination surge block and check valve. Measured groundwater quality field parameters during well development at OW-1, and observed purge water sediment content during well development at OW-2.  Collected groundwater samples from observation well OW-1 to establish baseline groundwater quality in the Qva aquifer. Analyzed the sample for petroleum hydrocarbon-related constituents and primary and secondary drinking water parameters. Measured groundwater quality field parameters immediately before sample collection. 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 7  Performed a “slug” test in OW-1 to estimate the hydraulic conductivity of the Qva aquifer.  Commenced long-term groundwater level monitoring in OW-1 in April 2016 by installing a Levelogger and a data logging barometer (Barologger). Commenced long-term groundwater level monitoring in the well at OW-2 in August 2016, installing a Levelogger. Performed periodic data downloads, coupled with manual readings of the OW-2 VWPs and dry wells IW -1 and IW-2.  Performed an inflow test in pilot dry well IW-1 by adding water at known rates for a selected time periods and monitoring water levels at IW-1 and OW-1 before, during, and after the inflow test. ― Step testing – performed four inflow steps at approximately 14, 38, 72, and 103 gallons per minute (gpm), maintaining each rate for approximately 1 hour; and ― Short-term constant rate injection test, lasting about 4.3 hours, at an average rate of about 110 gpm.  Performed an inflow test in full-scale dry well IW-2 by adding water at known rates for a selected time periods and monitoring water levels at IW-2, OW-2, and OW-1 before, during, and after the inflow test. ― Step testing – performed four inflow steps at approximately 87, 114, and 128 gpm, maintaining each rate for approximately 39 to 99 minutes; and ― Short-term constant rate injection test, lasting about 15.9 hours, at an average rate of about 141 gpm. 4.2 Findings 4.2.1 Observed Geologic Conditions Appendix A presents the exploration logs and includes a Soil Description and Log Key that explains the terms used in the soil classifications and descriptions. Figures 5 and 6 present in profile generalized illustrations of the subsurface conditions we observed at the four borings. The results of these borings and hydrogeologic information interpreted from other studies in the vicinity are summarized as follows:  Near-surface soils consisting primarily of Qvat and weathered Qvt extend to a depth of about 10 and 14 feet. Some surficial fill is also present.  Interbedded Vashon lodgement till (Qvt) and till-like deposits (Qvd) occur beneath the near-surface soils to about 38 to 50 feet bgs.  Interbedded Qva and Qvd layers are present below approximately 38 to 50 feet, to about 60 to 72 feet bgs. Perched groundwater was observed to about 61 feet bgs in these deposits. 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 8  Below about 60 to 61 feet bgs, encountered soils consisted predominantly of Qva, which are present to the maximum explored depth of 190 feet (approximately elevation 255 feet). Scattered layers of silty sand are present within the unsaturated Qva, particularly at and below about 134 to 147 feet (OW-1 and OW-2, respectively); some of these layers appear to be intermediate between Qva and Qvd.  Transitional bed deposits (Qtb) were not encountered by the project borings, but they may be present below the maximum exploration depth of 190 feet. Based on other deep explorations in the vicinity, Qtb deposits might be expected to occur below about 244 feet bgs (about elevation 201 feet). Soil treatment capacities of the Qva between the target UIC depth of about 120 feet and the top of the Qva regional aquifer are low to medium, as defined by the Guidance for UIC Wells that Manage Stormwater (Ecology, 2006). These treatment capacity rankings are based on the grain size analyses presented in Appendix B and summarized in Appendix C, Table C-4:  OW-1 vicinity: We observed approximately 10 cumulative feet of medium treatment capacity soils between 120 feet bgs and the top of the Qva regional aquifer; the remaining soils (about 37 feet cumulative thickness) have a low treatment capacity.  OW-2 vicinity: We observed approximately 14 cumulative feet of medium treatment capacity soils between 120 feet bgs and the top of the Qva regional aquifer; the remaining soils (about 33 feet cumulative thickness) have a low treatment capacity. 4.2.2 Groundwater Levels and Monitoring As indicated in the boring logs in Appendix A, we observed shallow wet seams and layers in the Qvat/weathered Qvt deposits at IW-1, OW-1, and OW-2. These were as shallow as 5.5 to 8.5 feet bgs in OW-1, about 9 to 14 feet bgs in IW-1, and about 12 feet bgs at OW-2. Similarly, we observed additional wet seams and layers within the Qvt/Qvd soils in the OW-2/IW-2 vicinity at about 23, 35, and 45 feet bgs. Perched groundwater may be feeding the wetlands identified on the site slopes (Shannon & Wilson, 2016a). We encountered a possible perched groundwater zone within the interbedded Qvd/Qva soils, between about 48 and 57 feet bgs at IW-1 and at about 50 to 53 feet bgs at OW-1. Perched water was present at IW-2 within the interbedded Qvd/upper Qva soils from about 49 to 61 feet bgs. Soil within this zone caved during drilling at IW-2, necessitating the installation of temporary surface casing. A possible zone of perched water was encountered at approximately 132.5 to 136.5 feet bgs at OW-1, associated with a silty sand Qva layer. However, this saturated zone may also have been associated with residual water introduced during the drilling process. 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 9 Hydrographs of the Qva aquifer groundwater levels measured to date at OW-1 and OW-2 are presented in Appendix C. The highest observed levels to date in the regional Qva aquifer at the site are approximately 167.1 to 167.3 feet bgs (elevation 278.0 to 277.4 feet) at OW-1 and OW-2, respectively. The range of fluctuation in the Qva aquifer water level observed to date is about 1.8 feet (April to November 2016 at OW-1). Apart from during and immediately after their respective injection well testing periods, wells IW-1 and IW -2 have been dry to date. The VWP installed at 66.3 feet bgs at OW-2 has also been dry, including during the IW-2 test. The VWP installed at 146.3 feet bgs at OW-2 measured water temporarily mounding at that depth during and immediately after the IW-2 test, as shown in Appendix C. The top of the unsaturated portion of the Qva unit is about 60 to 61 feet bgs (elevation 385 or 384 feet) in the OW-1/OW-2 vicinity. The unsaturated thickness of the targeted Qva infiltration receptor soils is about 72 feet (if perched water is present in the Qva at 132.5 feet bgs at OW-1) or about 106 feet (based on the highest groundwater level measured to date at OW-1). We estimated the Qva aquifer gradient by comparing groundwater elevations measured at the project wells to the approximate groundwater elevation we measured during a previous study at City of Edmonds observation well A-2 (Shannon & Wilson, 2013). Well A-2 is located about 4,500 feet west of the site. Based on these data, the Qva aquifer gradient beneath the project site is about 0.002 foot/foot to the west/northwest (Figure 4). 4.2.3 Aquifer Hydraulic Properties We performed single-well “slug” tests in observation well OW-1 to determine the local horizontal hydraulic conductivity (Kh) of the Qva aquifer (Appendix C). The OW-1 test results indicate a Kh of 55 feet/day (3.8 x 10-2 feet/minute). We estimated the Kh for soil samples collected from project borings IW-2, OW-1, and OW-2 using empirical methods (Table C-4, Appendix C). The results indicated the following: • The estimated Kh value for the till-like deposits (Qvd) sample from OW-1 was less than 0.01 foot/day. The Kh estimates for the 21 Qva unit samples range from 0.05 to 626 feet/day (3 x 10-5 to 0.43 feet/minute). Excluding the highest value as an outlier, the arithmetic and geometric mean Kh values of the remaining 20 samples are 38 and 11 feet/day (2.3 x 10-2 and 7.4 x 10-3 feet/minute), respectively. 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 10 4.2.4 Groundwater Quality In general, the OW-1 sample indicates that the groundwater quality of the Qva aquifer groundwater quality is good beneath the project site. An exception is the relatively high concentration of manganese, 344 parts per billion (ppb), which is almost seven times the secondary (aesthetic) drinking water standard of 50 ppb. Manganese occurs naturally in soil and groundwater. The extent to which manganese dissolves into groundwater depends on the amount of oxygen in the water and, to a lesser extent, upon the pH of the water. If the oxygen content of groundwater is low, manganese tends to dissolve more readily. The zone from which the OW-1 groundwater sample was collected contains scattered organics, the decomposition of which depletes the oxygen content of the groundwater. This may contribute to the relatively high groundwater manganese concentration. Table C-1 in Appendix C summarizes the laboratory test results for the OW-1 groundwater sample and comparable drinking water standards. Appendix C also contains the associated laboratory data report. 4.2.5 Pilot-scale Injection Well Testing Figure 7 presents the results of the pilot-scale injection well test at IW-1. During the first four injection steps (approximately 1 hour each, at about 14, 38, 72, and 103 gpm), the water column height in IW-1 ranged from approximately 2 to 18 feet (89 to 72 feet bgs). However, these four steps did not run long enough for the water level to stabilize. The fifth step lasted approximately 4.3 hours. The inflow rate varied between about 107 and 126 gpm during this step, with an average inflow rate of 110 gpm. At this inflow rate, the IW-1 water column height stabilized at approximately 24 feet, which is 67 feet below grade and 4 feet below the top of the well screen. Based on these data, and as summarized in Table C-3 (Appendix C):  The observed injection specific capacity of IW-1 is approximately 4.6 gpm/foot of water level rise and the approximate K for the tested zone is 24 feet/day (1.7 x 10-2 feet/minute).  The test did not cause the groundwater level in nearby observation well OW-1 to increase by a measurable amount. 4.2.6 Full-scale Injection Well Testing Figure 8 presents the results of the full-scale injection well test at IW-2. During the first three injection steps (which lasted between 39 and 99 minutes each at rates of 87, 114, and 128 gpm), the peak water column heights in IW -2 ranged from approximately 12 to 17 feet (or 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 11 108 to 103 feet bgs). However, the water level did not stabilize during these steps. The fourth step lasted for 15.9 hours, at an average inflow rate of about 141 gpm. At this inflow rate, the IW-2 water level was relatively stable at about 99 feet below grade, representing a head rise above the borehole bottom of about 21 feet. Based on these data, and as summarized in Table C- 3 (Appendix C):  The observed injection specific capacity of IW-2 is approximately 6.7 gpm/foot of water level rise and the approximate K for the tested zone is 30 feet/day (2.0 x 10-2 feet/minute.  The test caused the groundwater level in OW-2 VWP2 to rise by 5 feet at the end of the injection phase of the test. This rise fully dissipated during the subsequent 3.5 days. A small increase in the groundwater level (less than 0.3 foot) occurred in observation well OW-2 in response to the test. 5.0 GROUNDWATER MODELING OF PLANNED INJECTION WELLFIELD 5.1 Overview We performed groundwater modeling to determine the feasibility of the planned UIC wellfield. In particular, the modeling was conducted to evaluate potential groundwater mounding, well operational constraints, and the potential for seepage to occur at the slopes to the west of the UIC wellfield. The modeling consisted of the following: 1. Establishing a detailed conceptual site model; 2. Developing and calibrating the numerical model; 3. Simulating the planned 16-well UIC wellfield for a specified storm event; and 4. Testing the sensitivity of the model results to parameter uncertainty. Appendix D presents the full details of the modeling approach, results, and limitations. 5.2 Conceptual Site Model (CSM) Based on the four deep borings and our understanding of the local hydrogeology, we have developed the following CSM for the project site:  Relatively low permeability Qvt and Qvd soils are situated above a thick layer of relatively permeable Qva sand.  The upper Qva deposits are interbedded with Qvd soils down to a depth of 60 to 72 feet (elevation 385 to 373 feet). The base of the perched zone observed within the interbedded Qva/Qvd zone is 61 feet bgs (elevation 384 feet). The Qva is predominantly unsaturated from 61 to 167 feet bgs (elevations 384 to 278 feet). 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 12  The regional Qva aquifer extends from 167 feet bgs (elevation 278 feet) to at least 244 feet bgs (elevation 201 feet)  Potentially perching layers of silty sand are scattered within the generally unsaturated Qva. These layers occur primarily below 147 feet bgs (elevation 298 feet) at OW-1 and OW-2, and possibly as shallow as 134 feet bgs (elevation 311 feet) at OW-1.  At each deep UIC well, a surface casing and seal will be installed to isolate the overlying Qvt, Qvd, and saturated upper Qva layers from the unsaturated underlying Qva soils (Figure 9). Stormwater discharge to the UICs will be directed into the unsaturated Qva soils to a maximum depth of about 120 feet (about elevation 325 feet). 5.3 Model Development and Calibration The model uses the U.S. Geological Survey’s numerical groundwater flow code MODFLOW- 2005 (Harbaugh, 2005) to simulate the unsaturated zone and groundwater flow system in the project area. The model occupies an area 2,400 feet by 2,000 feet, and it extends from land surface to elevation 225 feet. The model uses the following three layers to simulate the subsurface soils described in the CSM:  Layer 1 – unsaturated Qva outwash (land surface to elevation 298 feet)  Layer 2 – a 5-foot thick, low permeability perching layer (from elevation 298 to 293 feet)  Layer 3 – saturated Qva outwash (elevation 293 to 225 feet) We calibrated the model transiently to the full-scale injection test performed using UIC well IW-2. This involved adjusting the material properties of the three layers to enable the model to best reproduce the observed changes in groundwater levels. Table D-1 in Appendix D present the final modeled material properties. 5.4 Model Simulation (Base Case) We used the calibrated model to simulate the planned UIC wellfield for a specified storm event. This Base Case involved the following:  16 UIC wells, grouped in four areas (Areas 1 through 4), each with three to five wells spaced at 30 to 50 feet (Figure 10);  The UIC wells inject water into model layer 1; and  The simulated injection was for a 100-year, 24-hour storm event. The peak hourly injection rate for each well ranged from 102 to 130 gpm. 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 13 The results indicate that the simulated storm event would temporarily raise water levels by up to 11 feet (to a peak elevation 310 feet) at the center of UIC Area 2 (135 feet bgs), and by up 7 feet (to elevation 306 feet) at the center of the three other UIC areas (139 feet bgs). Although some mounding interference would occur between adjacent UIC wells in each area, the operational groundwater level would not be higher than the top of the designed well screens (at elevation 375 to 380 feet). The model also predicts that the groundwater would not increase to less than 70 feet below land surface at the slope to the west of the wellfield areas. 5.5 Sensitivity Analysis To evaluate the effect on the Base Case results of key model parameter uncertainty, we performed three sensitivity cases. These involved the re-simulating the 24-hour storm with (a) the Qva aquifer Kh and Kv values reduced by a factor of 10, (b) the elevation of the 5-foot thick perching layer increased by 15 feet, and (c) a combination of (a) and (b). The most conservative case (c) results indicate that the induced perched water table would rise to a peak of elevation 328 feet at the center of UIC Area 2, which is 117 feet bgs. The water would remain more than 50 feet below the toe of the slope to the west of UIC Area 2. 6.0 STORMWATER QUALITY DISCUSSION We understand that the District plans to employ source controls and to treat site stormwater based on the expected pollutant loads, in accordance with the local stormwater code requirements (City of Edmonds, 2010; Ecology, 2005 and 2006). We understand that the District plans to incorporate bioretention for treatment and infiltration of some site stormwater, with drainage from the bioretention being routed to some of the UIC wells. This best management practice (BMP) will target shallow, unsaturated soils with moderate permeability, e.g., Qvat, fill, and weathered Qvt. In areas where these soils have sufficient permeability, some flow control benefit will be realized by this BMP. Additional flow control will be provided by the proposed UIC wells. The introduction of nutrients into UIC wells may contribute to biofouling of the wells, thereby reducing their effective life span (National Research Council [NRC], 1994). To manage phosphorus and nitrogen at the bioretention facilities, we recommend incorporating the following elements into the bioretention facility BMP design, in accordance with the applicable stormwater code (City of Edmonds, 2010) and as described in the Low Impact Development Technical Guidance Manual for Puget Sound (Puget Sound Action Team, 2005; Puget Sound Partnership, 2012): 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 14  Use only mature, stable compost, without biosolids or manure constituents.  Employ elevated under-drains to create a fluctuating anoxic/aerobic zone below the drain pipes. We contacted Ecology (Ms. Mary Shaleen-Hansen, Water Quality Section; Mr. Douglas Howie, Senior Stormwater Engineer) to discuss UIC management and common reasons for UIC well failure. Ms. Shaleen-Hansen recommended that the site UIC well management plan address coliform, pesticides, and herbicides (i.e., through source control) to prevent introduction of these contaminants into the UIC wells. Although Mr. Howie was not familiar with UIC well fouling due to the introduction of nutrients, he stated that UIC well failures are typically due to the introduction of total suspended solids (TSS). In our experience, TSS-fouled UIC wells are challenging to redevelop, even more so than biofouled wells. Therefore, sediment fouling should be avoided whenever possible. Part of an effective TSS management policy is to prevent construction site runoff from entering UIC wells, as it can have elevated TSS levels. UIC wells should be also protected from receiving runoff from recently landscaped areas until those areas have stabilized, in accordance with the locally applicable stormwater manual. 7.0 CONCLUSIONS AND RECOMMENDATIONS Based on our observations at the current borings and our previous site test pits and shallow borings, the infiltration potential of the site’s shallow native soils is generally low. Infiltration of some stormwater at dispersed facilities is feasible on portions of the site (Shannon & Wilson, 2016b). In general, shallow site soils are not feasible for the concentrated infiltration of large volumes of stormwater, but infiltration into the underlying unsaturated, relatively low-fines- content Qva soils is feasible. 7.1 Injection Well Recommendations 7.1.1 General We recommend that the UIC well construction activities of the District’s drilling contractor be observed by the District’s own hydrogeologic/geotechnical representative, under separate contract to the District. We recommend that the selected drilling contractor submit a drill plan and qualifications to the District’s hydrogeologic/geotechnical representative for approval prior to beginning work. During UIC well installation, we recommend that we provide field observation of UIC well installation and field testing, as the District’s representative, so that timely adjustments to array layout can be made, if needed. 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 15 Based on the IW-1 and IW-2 inflow tests, the use of UIC wells at the project site is feasible for stormwater management. The top of the target infiltration zone (unsaturated, sandy Qva soils with predominantly low fines content) is about 60 to 61 feet bgs at the locations explored by OW-1, OW-2, IW-1, and IW-2. The depth to this contact may vary across the site. Based on the OW-1 log, perched groundwater may be present in the Qva at about 132.5 feet bgs in that area. The top of the regional Qva aquifer is at about 167 feet bgs. Ecology does not allow stormwater to be discharged directly into an aquifer via UIC wells. We recommend that the UIC well depths be limited to about 115 to 120 feet (approximately 330 to 325 feet), which will allow for up to about 47 feet of separation between the UIC wells and the top of the Qva aquifer. We understand that the District proposes to install UIC wells in four array clusters, with UIC wells spaced approximately 30 to 50 feet apart (Figure 10). We recommend the wells be spaced no closer than 30 feet on center in order to reduce interference between the wells. Greater spacing creates less interference and results in more efficient UIC well operation. We recommend that the newly installed UIC wells be flow tested shortly after installation in order to confirm the expected UIC performance assumptions. 7.1.2 Well Design Recommendations There are two general types of deep UIC well designs in common use locally. These include: (a) large-diameter boreholes filled with sand and/or gravel infiltration media (with or without a vertical transmission casing and screen), and (b) traditional screened wells, which have a smaller filter-packed zone around the well screen or no artificial filter pack at all. Based on our communication with the project team, we understand that the former, option a, is planned for the project, and we have based our design recommendations on this understanding. Auger rigs are commonly used to perform this type of drilling. Auger drilling and installation techniques typically involve drilling a cased hole through the zone through which a seal will be placed and an open or temporarily cased hole in the infiltration receptor zone. Drilling is typically accomplished with a solid stem or bucket auger. Unit cost estimates for drilling and installing this type of UIC well are roughly $30,000 to $40,000, excluding surface vault and distribution system completion, spoils handling, well development, and field testing. Unit well drilling costs are greater if few wells are installed. Based on our explorations and testing and assuming similar conditions as encountered at by the four deep site borings, the recommended full-scale UIC well short-term specific capacity estimate is 6.7 gpm/foot of screen. Assuming good control over TSS and nutrients and relatively 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 16 uniform site conditions, we recommend applying a divisive correction factor (CF) of 2 to this UIC well capacity. Applying this CF results in a UIC well design specific capacity of about 3.3 gpm/foot of screen in the unsaturated Qva. This assumes the UICs will have similar construction to IW-2, with a minimum diameter of 24 inches and total depth of about 115 to 120 feet. Our UIC well design recommendations are presented below and are illustrated in Figure 9. Figure 9 conceptually illustrates construction aspects of a hybrid UIC well that combines infiltration media backfill with a vertical transmission casing and screen. The actual well depths and construction methods and details may differ, based on encountered hydrogeologic conditions and project goals. Construction steps include the following:  Drill a large-diameter hole (e.g., 36- to 40-inch) to facilitate construction of a surface seal. This borehole should be drilled to about 1 to 5 feet below the base of the Qvt/Qvd/saturated upper Qva soils (contact estimated to be about 60 to 65 feet bgs, or about elevation 385 to 380 feet). Maintain an open borehole through this upper zone using a temporary casing. The borehole diameter should be at least 4 inches larger than the nominal diameter of the planned permanent surface casing. Drill a smaller diameter hole (e.g., 24-inch) from the depth of the bottom of the planned permanent surface casing to about 50 to 60 feet into the unsaturated Qva soils (total depth of about 115 to 120 feet, or to about elevation 330 to 325 feet). Alternatively, temporary casing may be used to drill to the bottom of the hole. No drilling additives should be used, with the possible exception of water.  Install a permanent 30- to 36-inch inside diameter (I.D.) steel casing. This casing should be installed to about 1 to 5 feet below the base of the larger diameter hole. Construct a surface seal between the permanent casing and the borehole annulus. The intent of the surface seal is to (a) protect the Qva infiltration receptor soils from direct inflows of surface water and (b) prevent the draining of the overlying perched zones. Depending on drilling approach, the permanent surface casing and seal may be placed before or after the boring is drilled to its final depth and the vertical transmission casing/screen assembly is installed. We recommend the lower portion of the surface seal consist of bentonite chips (minimum 10 feet thick). Then place additional sealing material (bentonite, neat cement, or neat cement grout, in accordance with Washington Administrative Code (WAC) 173-160 sealing requirements) from the top of the bentonite chip seal to the ground surface. The lower bentonite chip seal should be installed in such a way so as to prevent the upper annular sealants from intruding into the target infiltration soils or the interior of the permanent surface casing.  Install the vertical transmission casing. We recommend using 8-inch I.D casing and screen. Concurrently install to the same depth a polyvinyl chloride (PVC) observation pipe casing and screen. (The purpose of the PVC pipe is to facilitate measurement of the water level in the UIC well during periods of stormwater inflow.) 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 17 Use steel centralizers on the 8-inch I.D. casing and screen, on about 20-foot centers, and secure the PVC pipe to the centralizers. Backfill the 24-inch borehole around the 8-inch I.D. screen with washed, rounded, UIC 4x8 filter sand. If temporary casing was not used to drill the lower borehole, it may be necessary to tremie the filter into place in order to reduce borehole wall caving. Extend the UIC 4x8 filter sand to about 5 feet above the depth of the permanent surface casing. Once the UIC 4x8 filter sand has been placed, we recommend using water to settle it around the screened zone, topping off the UIC 4x8 sand as necessary to bring it back to about 5 feet inside the permanent casing. We recommend placing UIC gravel around the pipes within the permanent surface casing, to approximately 4 feet below the planned invert of the inlet pipe into the permanent storm drain manhole (SDMH). Perform flow testing after the UIC gravel has been emplaced, topping off the gravel as necessary.  During installation of the permanent SDMH, we recommend placing two layers above the UIC gravel, consisting of a 6-inch minimum layer of UIC 4x8 filter sand and a 6-inch minimum layer of UIC filter sand. The intent of the UIC filter sand is to provide supplementary filtering of low-quantity UIC inflows. The UIC filter sand should be replaced as it becomes clogged. To protect the upper UIC filter sand from erosion, we recommend placing a pad of quarry spalls (approximately 6 inches thick) within the SDMH, with the top of the pad about 6 inches below the inlet pipe elbow. The permanent steel surface casing should be cut off approximately 3 feet below the invert of the inlet pipe to the SDMH.  To maintain UIC well function, it is critically important to protect the UIC wells from TSS loading while the site is under construction, as well as during normal site use. No construction-related stormwater should be discharged to the UICs, and the site should be fully stabilized prior to bringing the UICs online. Accordingly, we recommend that, while the site is under construction and not fully stabilized, and prior to installation of the permanent SDMH over a UIC, the UIC’s steel surface casing be left temporarily slightly above grade. We recommend that the top of the surface casing be temporarily protected with a welded top plate or a locking monument until the permanent SDMH is installed. During UIC operation, we recommend a combination of source control measures and pre-treatment to the site stormwater to remove or reduce the expected types and quantities of pollutants prior to its being discharged to the UIC arrays, in accordance with the local stormwater code (City of Edmonds, 2010) and the UIC Guidance (Ecology, 2006). 7.1.3 Injection Well Materials We recommend the following materials be used for UIC well construction:  UIC Vertical Transmission Casing, Screen, and Bottom Cap. Due to its high durability and high open area relative to PVC machine-slotted screen, we recommend using stainless steel screen in the UIC wells. The recommended UIC vertical 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 18 transmission casing, screen, and bottom cap material is 8-inch I.D., 304 stainless steel, with threaded or welded joints. The recommended screen is continuous-slot (0.020-inch slots), approximately 50 feet long. Steel centralizers on approximately 20-foot centers are recommended to facilitate placement of the casing in the center of the borehole. We recommend that the screened interval be installed in a borehole with a diameter of approximately 24 to 36 inches.  UIC Observation Pipe Casing, Screen, and Bottom Cap. The recommended UIC vertical observation pipe casing, screen, and bottom cap material is 2-inch I.D., Schedule 40 or Schedule 80 PVC with threaded joints. The recommended screen is factory machine-slotted (0.020-inch slots), approximately 10 feet long. We recommend that the top of the pipe be equipped with a removable watertight plug. We recommend that the PVC pipe be secured to the transmission casing centralizers.  UIC Surface Casing and Seal. The recommended UIC surface casing is steel, 30- to 36-inch I.D., meeting ASTM International A53 A or B, with 0.375-inch wall thickness and with welded or threaded joints. We recommend the surface casing be installed in a borehole that is at least 4 inches larger in diameter than the nominal surface casing diameter. We recommend seal materials meeting the WAC 173-160 Sealing Material Standard be placed in the annulus between the permanent steel surface casing and the borehole wall. We recommend that the bottom of the annular seal material consist of bentonite chips (minimum 10 feet thick). Above the bentonite chips, we recommend that the annular seal consist of neat cement, neat cement grout, or bentonite, in accordance with WAC 173-160.  UIC Filter Sand. We recommend the UIC filter sand meet the Ecology (2005) sand medium specification, with a recommended gradation of: U.S. Standard Sieve Size Percent Passing ⅜ (9.5 millimeter [mm]) 100 4 (4.75 mm) 95 to 100 8 (2.36 mm) 70 to 100 16 (1.18 mm) 40 to 90 30 (0.60 mm) 25 to 75 50 (0.30 mm) 2 to 25 100 (0.15 mm) <4 200 (0.075 mm) <2  UIC 4x8 Filter Sand. We recommend the UIC 4x8 filter sand consist of free- draining, rounded, granular material, with a gradation of: 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 19 U.S. Standard Sieve Size Percent Passing ⅜ (9.5 mm) 100 4 (4.75 mm) 60 to 95 8 (2.36 mm) 0 to 10 30 (0.60 mm) 0 to 2 200 (0.075 mm) 0 to 0.5  UIC Gravel. We recommend the UIC gravel consist of free-draining, rounded, granular material, with a gradation of: U.S. Standard Sieve Size Percent Passing ½ (12.5 mm) 100 ⅜ (9.5 mm) 80 to 100 4 (4.75 mm) 5 to 15 8 (2.36 mm) 0 to 10 100 (0.15 mm) 0 to 0.6 Filter materials used in UIC construction should be should be:  Free from organics, debris, or other deleterious material.  Stockpiled in such manner that they are protected from contamination by other site materials (e.g., fine sediment) and from segregation by rainfall, as appropriate. 7.2 Additional Recommendations We recommend that the performance of the UIC clusters be monitored so that UIC array performance over time can be tracked and appropriate maintenance or UIC well rehabilitation scheduled. We recommend the installation and monitoring of data logging transducers in some or all of the wells, coupled with periodic manual water level measurements. We recommend that a regular and perpetual maintenance program be performed for all of the site infiltration facilities to reduce siltation and bio-fouling, in accordance with the local stormwater code requirements. Groundwater observation wells should be protected through the facility construction process and be used to facilitate measurement of facility performance. If the wells are damaged during construction, they should be repaired or properly abandoned, in accordance with WAC 173-160. If the District desires to monitor the downstream effects of the planned UIC array, then we would recommend the installation of downgradient observation wells prior to the UIC arrays being brought online. Such wells could function as monitoring points for measuring variations in Qva aquifer water levels (and, if desired, for tracking aquifer water quality over time). Appropriate locations for such wells are to the west/northwest of the planned UIC arrays. These might be 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 20 drilled at or beyond the toe of the slope but still on the District property. If these wells are installed, then an additional observation well installed upgradient (east) of the UIC array would also be useful in measuring Qva aquifer water levels and possibly background water quality. As indicated by Figure 4, the project site is within the mapped ten-year time-of-travel zone of the water supply protection area for the Deer Creek municipal water supply surface water source. We recommend coordinating stormwater infiltration efforts in the project area with the Olympic View to facilitate their compliance with Washington State Department of Health source water protection requirements established under the Watershed Control Program. Olympic View’s water supply protection plan (plan) for Deer Creek (PACE, 2002) notes that Olympic View does not maintain any authority over land use regulations and requirements. However, Olympic View’s plan recommends the following regulatory and protective measures be considered by land use agencies (i.e., City of Edmonds), as applicable to the ten-year capture zone illustrated in Figure 4:  Encourage public education as being critical to the overall effectiveness of protecting the Deer Creek water supply.  Discourage use of chemical fertilizers.  Require that oil- and detergent-based waste materials be treated by the sanitary sewer system, as appropriate.  Encourage protection of surface water bodies and groundwater wells through public awareness.  Cooperate with land use and emergency response agencies (i.e., implement a spill response plan, with accompanying notification of the proper authorities and Olympic View of potential threats to the water supply system). 8.0 LIMITATIONS The analyses, conclusions, and recommendations contained in this report are based on site conditions as they presently exist. We assume that the current field explorations are representative of the subsurface conditions at the proposed infiltration facilities; i.e., the subsurface conditions everywhere in the vicinity of the proposed infiltration facilities are not significantly different from those disclosed by the field explorations. Within the limitations of the scope, schedule, and budget, the analyses, conclusions, and recommendations presented in this report were prepared in accordance with generally accepted professional geotechnical and hydrogeologic principles and practice in this area at the time this report was prepared. We make no other warranty, either express or implied. These conclusions and recommendations were based on our understanding of the project as described in this report and the site conditions as 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 22 9.0 REFERENCES CDM, 2006, Geotechnical data report, Brightwater conveyance system, west contract, Report prepared for King County Department of Natural Resources and Parks, Wastewater Treatment Division, by CDM, Bellevue, Wash., July. City of Edmonds, 2010, Stormwater code supplement to Edmonds Community Development Code Chapter 18.30: Edmonds, Wash., April 20. Harbaugh, A.W., 2005, MODFLOW-2005: the U.S. Geological Survey modular ground-water model -- the ground-water flow process: U.S. Geological Survey Techniques of Water- Resources Investigations Book 6, Chapter A16, 1v., available: https://pubs.usgs.gov/tm/2005/tm6A16/. Minard, J.P., 1983, Geologic map of the Edmonds east and part of the Edmonds west quadrangles, Washington: U.S. Geological Society MF-1541, 1:24,000 scale. National Research Council (NRC), 1994, Ground water recharge using waters of impaired quality: Committee on ground water recharge, Water science and technology board, Commission on geosciences, environment, and resources: National Academy Press, Washington, D.C., 304 p. Penhallegon Associates Consulting Engineers, Inc. (PACE), 2002, Deer Creek water supply protection plan: Report prepared by PACE, Kirkland, Wash., for Olympic View Water & Sewer District, Edmonds, Wash. Puget Sound Action Team, 2005, Low impact development technical guidance manual for Puget Sound: Olympia, Wash., publication no. PSAT 05-03, May. Puget Sound Partnership, 2012, Low impact development technical guidance manual for Puget Sound: Tacoma, Wash., December. Shannon & Wilson, Inc. (Shannon & Wilson), 2013, Final infiltration study report, SW Edmonds basin study projects #1 and #3, Edmonds, Wash.: Report prepared by Shannon & Wilson, Inc., Seattle, Wash., project no. 21-1-21768-001, for City of Edmonds, Edmonds, Wash., April 5. Shannon & Wilson, Inc. (Shannon & Wilson), 2016a, Revised wetland and stream delineation report, New Madrona K-8 Project, City of Edmonds, Wash.: Report prepared by Shannon & Wilson, Inc., Seattle, Wash., project no. 21-1-22082-002, for Edmonds School District #15, Lynnwood, Wash., August 4. 21-1-22082-003-R1f/wp/lkn 21-1-22082-003 23 Shannon & Wilson, Inc. (Shannon & Wilson), 2016b, Geotechnical engineering report, New Madrona K-8 Project, 9300 236th Street SW, Edmonds, Wash.: Report prepared by Shannon & Wilson, Inc., Seattle, Wash., project no. 21-1-22082-004, for Edmonds School District #15, Lynnwood, Wash., October 31. Thomas, B. E.; Wilkinson, J. M.; and Embrey, S. S., 1997, The ground-water system and ground- water quality in western Snohomish County, Washington: U.S. Geological Survey Water- Resources Investigations Report 96-4312, 218 p., 9 plates. Washington State Department of Ecology (Ecology), 2005, Stormwater management in Western Washington: Olympia, Wash., publication no. 05-10-31, 5 v., February. Washington State Department of Ecology (Ecology), 2006, Guidance for UIC wells that manage stormwater: Olympia, Wash., publication no. 05-10-067, December. Washington State Department of Ecology (Ecology), 2016a, Washington State water resources explorer: Available: https://fortress.wa.gov/ecy/waterresources/map/WCLSWebMap/WaterResourcesExplorer.as px , accessed November 17, 2016. Washington State Department of Ecology (Ecology), 2016b, Washington State well log viewer: Available: https://fortress.wa.gov/ecy/waterresources/map/WCLSWebMap/default.aspx , accessed November 17, 2016. 104 NE 205th St 238th St SW 236th St SW 240th St SW Lake Ballinger PROJECT LOCATION 99 5 VICINITY MAP FIG. 1 Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington Map adapted from aerial imagery provided by Google Earth Pro, reproduced by permission JUDQWHGE\*RRJOH(DUWKŒ0DSSLQJ6HUYLFH NOTE November 2016 21-1-22082-003 Fi l e n a m e : J: \ 2 1 1 \ 2 2 0 8 2 - 0 0 3 \ 2 1 - 1 - 2 2 0 8 2 - 0 0 3 v i c m a p . d w g D a t e : 11 - 0 7 - 2 0 1 6 L o g i n : MJ M Seattle Tacoma Washington Project Location 90 5 MT 97 0 2,000 4,000 Approximate Scale in Feet DP-6 DP-2 DP-7 DP-4 DP-5 DP-3 DP-1 OW-1 IW-1 A A' OW-2 IW-2 B B' SITE AND EXPLORATION PLAN FIG. 2 Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington Map adapted from aerial imagery provided by Google Earth Pro, UHSURGXFHGE\SHUPLVVLRQJUDQWHGE\*RRJOH(DUWKŒ0DSSLQJ6HUYLFH NOTE November 2016 21-1-22082-003 Fi l e n a m e : J: \ 2 1 1 \ 2 2 0 8 2 - 0 0 3 \ 2 1 - 1 - 2 2 0 8 2 - 0 0 3 S i t e . d w g D a t e : 11 - 1 6 - 2 0 1 6 L o g i n : MJ M MT 0 200 400 Scale in Feet Data Point and Designation Wetland Boundary Wetland Buffer Observation Well Designation and Approximate Location Dry Well Designation and Approximate Location Generalized Subsurface Profile LEGEND WETLAND A CATEGORY IV WETLAND C CATEGORY IV WETLAND B CATEGORY III DP-2 60 Foot Buffer 40 Foot Buffer OW-1 IW-1 A Map adapted from 1:24,000 USGS geologic map of the Edmonds East and Part of the Edmonds West, WA quadrangle, dated 1983. NOTE SHANNON & WILSON, INC. SURFICIAL GEOLOGIC MAP FIG. 3 21-1-22082-003 Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington November 2016 Fi l e n a m e : J: \ 2 1 1 \ 2 2 0 8 2 - 0 0 3 \ 2 1 - 1 - 2 2 0 8 2 - 0 0 3 G e o m a p . d w g D a t e : 11 - 1 6 - 2 0 1 6 L o g i n : MJ M 0 2000 4000 Approximate Scale in Feet -Modified Land -Landslide Deposits -Vashon RecessionalOutwash -Vashon Till -Vashon Advance Outwash -Transitional Beds -Whidbey Formation LEGEND ml Qls Qvr Qvt Qva Qtb Qw PROJECT SITE Deer Creek Treatment Plant Controlled Watershed Boundary 1 Year Zone 5 Year Zone 10 Year Zone Buffer Zone PROJECT SITE City of Edmonds Observation Well A-2 (BHR 847) Domestic Well Groundwater Right Claim G1-163674CL Olympic View Water & Sewer District Test Well BIY 700 FI G . 4 DEER CREEK WATER SUPPLY PROTECTION AREA MAP FIG. 4SHANNON & WILSON, INC. Filename: J:\211\22082-003\21-1-22082-003 Fig 4.dwg Date: 11-18-2016 Login: SAC 21-1-22082-003 Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington November 2016 LEGEND Non-Project Well Designation and Approximate Location Approximate Aquifer Gradient Direction 0 2000 4000 Approximate Scale in Feet NOTES 1.Base map taken from Deer Creek Water Supply Protection Plan, (PACE, 2002). 2.Aquifer gradient direction based on project wells and City of Edmonds Well A-2. Approximate gradient equals 0.002 feet/foot. 200 250 300 350 400 450 500 Ap p r o x i m a t e E l e v a t i o n i n F e e t West A East A' 200 250 Possible Perched Zone (May be due to water added during drilling) 300 350 400 450 500 Ap p r o x i m a t e E l e v a t i o n i n F e e t Project Area (Proj. 0') OW-1 (Proj. 9' S) IW-1 Wetland BWetland C (Proj. 68' S) Hf/Qvat/weathered Qvt Qvt Qvd/Qva Qvd/Qva Qva, unsaturated Existing Ground Surface Qtb (Extrapolated from Non-Project Deep Borings in Vicinity) Qvd/Qvt 150150 Qva/Qvd 04-21-16 QV D QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A T QV T QV T QV D QV A QV A QV A QV A 04-07-16 QV A T QV T QV T QV D QV D QV D QV A QV D QV A QV A (Moved 50 E for Clarity) DR Y Silty Sand Qva Layers Qva, Saturated SHANNON & WILSON, INC. Fi l e n a m e : J: \ 2 1 1 \ 2 2 0 8 2 - 0 0 3 \ 2 1 - 1 - 2 2 0 8 2 - 0 0 3 S i t e . d w g L a y o u t : Pr o f i l e A D a t e : 11 - 1 8 - 2 0 1 6 L o g i n : SA C GENERALIZED SUBSURFACE PROFILE A-A' FIG. 5 November 2016 Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington 21-1-22082-003 Vertical Exaggeration = 4X Seep Regional Groundwater Level Perched Groundwater Level LEGEND (Proj. 9' S) IW-1 Observation Well Designation Dry Well Designation Projection Distance and Direction Ground Surface Possible Perched Zone Approximate Geologic Contact Vibrating Wire Piezometer Filter Pack Well Screen Bottom of Well ?? Fill Vashon Ablation Till Vashon Lodgement Till Vashon Till-like Deposits Vashon Advance Outwash Transitional Beds (Fine Grained) Hf Qvat Qvt Qvd Qva Qtb OW-1 GEOLOGIC UNIT 0 50 100 Vertical Scale in Feet 0 200 400 Horizontal Scale in Feet IW-1 IW-2OW-1 OW-2 North B' South B 300 500 Qva, saturated Qvt/Qvd Hf/Qvat/weathered Qvt Qvd/Qvt Qvd/Qva Qva/Qvd Qvd/Qva Qva/Qvd Qvd/Qva Qva, unsaturated Silty Sand Qva Silty Sand Qva Silty Sand Qva Qtb, (Extrapolated from non-project deep borings in vicinity) 140 QV A T QV T QV T QV D QV D QV D QV A QV D QV A QV A 04-21-16 HF QV A T QV T QV T QV D QV A QV D QV D QV A QV A QV A QV A 10-06-16 QV A T QV T QV T QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A 04-07-16 HF HF QV A T QV T QV T QV D QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV A QV D QV A QV A QV A QV A QV A 08-19-16 340 380 420 460 260 220 180 Ap p r o x i m a t e E l e v a t i o n i n F e e t 300 500 140 340 380 420 460 260 220 180 Ap p r o x i m a t e E l e v a t i o n i n F e e t DR Y DR Y DR Y DR Y Possible Perched Zone (May be due to water added during drilling) SHANNON & WILSON, INC. Fi l e n a m e : J: \ 2 1 1 \ 2 2 0 8 2 - 0 0 3 \ 2 1 - 1 - 2 2 0 8 2 - 0 0 3 S i t e . d w g L a y o u t : Pr o f i l e B D a t e : 11 - 1 8 - 2 0 1 6 L o g i n : SA C GENERALIZED SUBSURFACE PROFILE B-B' FIG. 6 November 2016 Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington 21-1-22082-003 Vertical Exaggeration = 2.5X Seep Regional Groundwater Level Perched Groundwater Level LEGEND (Proj. 9' S) IW-1 Observation Well Designation Dry Well Designation Projection Distance and Direction Ground Surface Possible Perched Zone Approximate Geologic Contact Vibrating Wire Piezometer Filter Pack Well Screen Bottom of Well Fill Vashon Ablation Till Vashon Lodgement Till Vashon Till-like Deposits Vashon Advance Outwash Transitional Beds (Fine Grained) Hf Qvat Qvt Qvd Qva Qtb OW-1 GEOLOGIC UNIT 0 40 80 Vertical Scale in Feet 0 100 200 Horizontal Scale in Feet IW-1-IW-1 Plot LL-11/22/2016-pvh 10 20 30 40 50 60 70 80 90 100 110 120 13061 66 71 76 81 86 91 0 100 200 300 400 500 600 700 800 900 1000 Ap p r o x i m a t e I n f l o w R a t e ( g p m ) Wa t e r D e p t h B e l o w G r a d e ( F e e t ) Elapsed Time (Minutes) Top of Screen Depth Bottom of Screen Depth IW-1 Transducer Data Approximate Inflow Rate FI G . 7 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington INFLOW TEST RESULTS AT PILOT UIC WELL IW-1 November 2016 21-1-22082-003 FIG. 7SHANNON& WILSON, INC. Geotechnical and Environmental Consultants NOTES 1.The dry well injection test at test well IW -1 was performed from 10:03 to 18:34 on 4/25/2016. IW -1 is screened at approximately 63.3 to 90.4 feet below grade, with filter pack from 59.2 to 91.2 feet deep. Borehole diameter was approximately 10.5 inches, drilled to 91.2 feet. 2. Tap water (44,107 gallons) was introduced at the top of the 6-inch-diameter PVC casing, using a fire hydrant. 3. gpm = gallons per minute 4. Fire hydrant flow became inconsistent late in test, possibly due to increased local water demand. 5. Black and white reproduction of this color original may lead to incorrect interpretation. Approximate Infiltration Specific Capacity 4.6 gpm/ft IW-2-IW-2 Plot LL-11/22/2016-pvh 0 20 40 60 80 100 120 140 16050 60 70 80 90 100 110 120 130 0 200 400 600 800 1000 1200 1400 1600 1800 Ap p r o x i m a t e I n f l o w R a t e ( g p m ) Wa t e r D e p t h B e l o w G r a d e ( F e e t ) Elapsed Time (Minutes) Top of Exposed Screen Depth Bottom of Screen Depth IW-2 Transducer Data IW-2 Manual Water Level Data Approximate IW-2 Inflow Rate FI G . 8 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington INFLOW TEST RESULTS AT FULL-SCALE UIC WELL IW-2 November 2016 21-1-22082-003 FIG. 8SHANNON& WILSON, INC. Geotechnical and Environmental Consultants NOTES 1.The injection test at dry well IW-2 was performed from 10/11/2016 9:09 to to 4:09 on 10/12/2016. IW -2 screen is approximately 28.3 to 119.7 feet below grade, with filter pack from about 3 to 120.4 feet deep. Filter-packed hole diameter is 30 inches from 0 to about 44 feet and approximately 24 inches from 44 to 120.4 feet. Steel 30-inch-diameter surface casing was sealed in place to 60.5 feet deep. The surface seal extends down to about 62 feet deep. 2. Tap water (153,933 gallons) was introduced at the top of the filter-packed borehole, using a fire hydrant. 8-inch stainless steel screen (20-slot) is exposed to the formation from about 62 to 119.7 feet. 3. gpm = gallons per minute 4. Black and white reproduction of this color original may lead to incorrect interpretation. Approximate Infiltration Specific Capacity 6.7 gpm/ft CONCEPTUAL UIC WELL DESIGN FIG. 9SHANNON & WILSON, INC. November 2016 NOTES 1.Surface casing and seal to conform to WAC 173-160. 2.Employ best management practices, as appropriate and following approved stormwater manual, to provide any required pre-treatment to water discharged to UIC wells. 3.3URYLGHVWHHOFHQWUDOL]HUVIRU‘FDVLQJDQGVFUHHQ installed on approximately 20' spacing. Fi l e n a m e : J: \ 2 1 1 \ 2 2 0 8 2 - 0 0 3 \ 2 1 - 1 - 2 2 0 8 2 - 0 0 3 F i g 9 . d w g D a t e : 11 - 2 2 - 2 0 1 6 L o g i n : BD D Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington 21-1-22082-003 Not to Scale Minimum 5' * Seasonal High Qva Aquifer Water Level *(Required separation may be greater depending on pre-treatment, groundwater mounding potential, vadose zone treatment capacity, and pollutant loading.) Unsaturated Qva Deposits Base of Qvt/Qvd or Base of Perched Qvd/Qva Aquifer, Whichever is Deeper Geologic Contact (Est. Depth 60-70', As Identified by Engineer's Representative) 1-5' Below Contact ‘7KUHDGHG6FKRU6FK 80 PVC Blank Casing, Top Min. $ERYH7RSRI‘&DVLQJ Qva Aquifer Temporary UIC Well Vault with Welded or Locking Cover (To Be Replaced Later By Storm Drain Manhole) Stormwater from Distribution Manifold, Pretreated As Appropriate ‘%RUHKROH0LQ/DUJHU7KDQ Surface Casing ‘6WDLQOHVV6WHHO%ODQN Casing, Threaded or Welded Joints Quarry Spalls Pad (~6" Thick) UIC 4x8 Filter Sand, Washed, Rounded a RI‘&RQWLQXRXV6ORW 304 Stainless Steel Screen (0.020" slots), Threaded or Welded Joints. UIC Filter Sand for Supplementary Filtering (Min. 6" Thick, To Replace as Needed) ‘%RUHKROH ‘7KUHDGHGRU:HOGHG 304 Stainless Steel End Cap UIC 4x8 Filter Sand, Washed, Rounded (Min. 6" Thick) Bentonite, Neat Cement, or Neat Cement Grout Seal ~115-120' Bentonite Chip Seal (Min. 10' Thick) UIC Gravel, Washed, Rounded ‘7KUHDGHG39&(QG&DS a RI‘7KUHDGHG0DFKLQH Slotted, Sch. 40 or Sch. 80 PVC Screen (0.020" Slots) 6WHHO6XUIDFH&DVLQJ ‘ Wall Thickness) OBS-1 OW-2 Fi l e n a m e : J: \ 2 1 1 \ 2 2 0 8 2 - 0 0 3 \ 2 1 - 1 - 2 2 0 8 2 - 0 0 3 F i g 1 0 - P r o p o s e d W e l l A r r a y M a p . d w g L a y o u t : La y o u t D a t e : 11 - 2 9 - 2 0 1 6 L o g i n : BD D SHANNON & WILSON, INC. PROPOSED UIC WELL ARRAY MAP FIG. 10 November 2016 Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington 21-1-22082-003 IW-2 Existing UIC Well Designation and Approximate Location Proposed UIC Well Designation and Approximate Location Proposed UIC Well Custer Designation LEGEND NOTE Figure adapted from client file received 11-4-16. 0 100 200 Approximate Scale in Feet IW-2 (Inflow tested 10-11 to 10-12-2016) Mounding Analysis Model Hypothetical Observation Point Designation and Approximate Location Existing Observation Well Designation and Approximate Location OBS-1 OW-2 OBS-3 OBS-5 OBS-6 OBS-4 OBS-7 (220 Feet) 21-1-22082-003 APPENDIX A SUBSURFACE EXPLORATIONS 21-1-22082-003-R1f-AA/wp/lk 21-1-22082-003 A-i APPENDIX A SUBSURFACE EXPLORATIONS TABLE OF CONTENTS Page A.1 GENERAL ...................................................................................................................... A-1 A.2 SOIL BORINGS ............................................................................................................. A-1 A.2.1 Sonic Core Borings ........................................................................................... A-1 A.2.2 Auger Boring .................................................................................................... A-2 A.3 SOIL SAMPLING AND LOGGING ............................................................................. A-3 A.4 WELL AND VIBRATING WIRE PIEZOMETER (VWP) INSTALLATION ............. A-3 TABLES A-1 Summary of Well Installation Details A-2 Summary of Vibrating Wire Piezometer Installation Details FIGURES A-1 Soil Description and Log Key (3 sheets) A-2 Log of Sonic Core IW-1 A-3 Log of Boring IW-2 A-4 Log of Sonic Core OW-1 A-5 Log of Sonic Core OW-2 21-1-22082-003-R1f-AA/wp/lk 21-1-22082-003 A-1 APPENDIX A SUBSURFACE EXPLORATIONS A.1 GENERAL The subsurface exploration program for the project was conducted by Shannon & Wilson, Inc. (Shannon & Wilson). The purpose of the exploration program was to evaluate the feasibility of deep underground injection control (UIC) wells for use in project site stormwater management. The subsurface exploration program consisted of three sonic core soil borings and one auger boring. The sonic core borings included a pilot UIC well (IW-1) and two observation wells (OW-1 and OW-2). Holt Services, Inc. (Holt) of Edgewood, Washington, completed the sonic core borings between April 4 and 21, 2016 (OW-1, IW-1), and between August 17 and 19, 2016 (OW-2), under subcontract to Shannon & Wilson. A full-scale UIC well (IW-2) was installed in the auger boring. Malcolm Drilling Company, Inc. (Malcolm) of Kent, Washington, completed IW-2 between October 5 and 6, 2016, under subcontract to Shannon & Wilson. We measured the approximate well locations in relation to previously mapped site features. PACE Engineers, Inc. provided surveyed well monument lid elevations for OW-2 and IW-2, and we measured the approximate monument and grade elevations at IW-1 and OW-1 based on the data provided for OW-2. Figure 2 shows the approximate exploration locations. Figure A-1 presents a Soil Description and Log Key that explains the terms used in the soil classifications and descriptions. The logs of the soil borings are presented as Figures A-2 through A-5. Approximate grade elevations are presented on the logs. A.2 SOIL BORINGS A.2.1 Sonic Core Borings Holt drilled the sonic core soil borings using a track-mounted, Terra Sonic International 150CC Compact Crawler sonic drill rig. Observation well boring OW-1 was completed on April 7, 2016, to a depth of 185.5 feet below ground surface (bgs). The pilot UIC well boring (IW-1) was completed on April 21, 2016, to 91.2 feet bgs. Observation well boring OW-2 was completed on August 19, 2016, to 190 feet bgs. Holt used the rotosonic (sonic) drilling method to drill the borings. Sonic drilling uses high-frequency vibratory motion applied to the top of the drill column, along with down pressure 21-1-22082-003-R1f-AA/wp/lk 21-1-22082-003 A-2 and rotation, to obtain nearly continuous core samples of soil. Soil samples were obtained using a 4-inch inside diameter (I.D.) core barrel for the observation well installation and a 7-inch I.D. core barrel for the pilot UIC well installation. As the drill column was advanced into the ground, soil entered the core barrel. After advancing the core barrel (termed a core “run”), the core barrel was removed from the borehole, and the soil core was extracted from the core barrel into labelled plastic bags. Each core run was typically about 10 feet long, although shorter runs were used in harder drilling situations. After retrieval of the soil core for a specific interval, a temporary casing was vibrated to the bottom of the sampled interval. The casing was then cleared of slough, and the drill column and core barrel were advanced, starting at the bottom of the temporary casing. Drilling and sampling progress was generally easier at the larger diameter sonic core boring, IW-1, where the 7-inch core barrel was used, than at OW-1 and OW-2, where the 4-inch core barrel was used. The fines content in some samples appeared to be lower in the larger diameter IW-1 sonic core samples that in the smaller diameter sonic core samples collected from OW-1 at the same depths. Holt’s opinion was that the larger diameter tooling used at IW-1 allowed coarse gravels and cobbles to more easily enter the core barrel during sampling. When penetrating unsaturated soils, sonic core drilling and sampling were also easier if water was added during the sampling runs. Generally, the sonic core runs were drilled without adding water, so that the locations of perched groundwater zones, if any, could better be estimated. Holt drummed the sonic core drill cuttings and spoils, removing them for disposal after the completion of each sonic core boring. A.2.2 Auger Boring Malcolm completed the full-scale UIC well IW-2 on October 6, 2016, to 120.4 feet bgs. Malcolm used a Bauer BG-24 track-mounted auger drill rig to drill IW-2. Malcolm initially drilled open-hole to about 56 feet bgs. Some caving occurred at 51 to 56 feet, so Malcolm proceeded to install temporary (one-meter diameter) casing to maintain an open borehole to 61 feet. Malcolm drilled the remainder of the boring open-hole with 24-inch auger. Malcolm used a crane to install the permanent steel surface casing to 60.5 feet deep prior to completing the drilling of the boring. Malcolm placed the 30-inch I.D. steel surface casing to 60.5 feet deep and sealed it in place. Before placing the permanent surface casing, a bentonite chip seal was installed at 59.5 to 62 feet. The 30-inch I.D. casing was then temporarily backfilled with cuttings to 30 feet deep and cemented in place. The temporary one-meter diameter casing was then removed, and the cement was allowed to cure overnight. The top of cement was 10 feet bgs the 21-1-22082-003-R1f-AA/wp/lk 21-1-22082-003 A-3 next morning, and bentonite chip seals were placed from 7 to 10 feet bgs and at 0 to 1 foot. The temporary backfill placed at 1 to 7 feet consisted of filter sand. The upper 10 feet of temporary annular backfill will be replaced when the project moves to construction. Cement was found to have intruded the temporary spoils inside the 30-inch casing up to about 44 feet below grade; this material was drilled out using a 24-inch solid stem auger and was separately stockpiled from the other borehole cuttings. Some caving was experienced during drilling at about 51 feet and again at about 99 feet; these zones are identified on the boring log. Malcolm switched from a solid stem auger to a bucket auger at 101.5 feet deep to reduce caving. Auger boring IW-2 was drilled without adding water. We noted that the fines content of the auger cuttings appeared to be lower than that observed in the samples collected from similar depths at adjacent the OW-2 sonic core boring (Appendix B). Most of the auger spoils from the IW-2 boring were disposed of by Clearcreek Contractors, Inc., of Marysville, Washington. Auger spoils that were intruded by cement during the installation of the permanent IW-2 surface casing seal were disposed of by Bravo Environmental NW, Inc., of Seattle, Washington, under subcontract to Malcolm. A.3 SOIL SAMPLING AND LOGGING Shannon & Wilson representatives observed and logged the drilling operations at each of the sonic core borings (IW-1, OW-1, and OW-2) and the auger boring (IW-2). We photographed and collected sub-samples of the IW-1 and OW-2 soil cores in field, and also logged cuttings and collected grab samples from the auger boring, IW-2. Shannon & Wilson geologists logged and photographed the OW-1 soil cores in Shannon & Wilson’s warehouse. Shannon & Wilson geologists also reviewed the IW-1, IW-2, and OW-2 photographs and samples. We transferred representative soil samples collected from the soil cores and auger cuttings to our Seattle, Washington, laboratory for analysis (see Appendix B). The boring logs in this report represent our interpretation of the field logs. A.4 WELL AND VIBRATING WIRE PIEZOMETER (VWP) INSTALLATION For the sonic core borings IW-1, OW-1, and OW-2, the wells were installed through the temporary casing, which was withdrawn as the annular backfill was placed. The wells were constructed of threaded Schedule 40 polyvinyl chloride (PVC) casing and machine-slotted (0.020-inch) PVC screen. The PVC casing was 6-inch I.D. for IW-1 and 2-inch I.D. for OW-1 and OW-2. The screened intervals were filter-packed with No. 10-20 Colorado silica sand. A bentonite chip surface seal was placed above each well’s filter-packed zone. 21-1-22082-003-R1f-AA/wp/lk 21-1-22082-003 A-4 In addition to the observation well, two VWPs were installed in OW-2. VWP1 was placed in a zone suspected of potentially containing perched water (at 66.3 feet bgs). VWP2 was placed in a zone where water might be expected to perch during an inflow test (at 146.3 feet bgs). The vertical transmission casing for UIC well IW-2 was constructed of threaded, 304 stainless steel, 8-inch I.D. blank casing and continuous-slot (0.020-inch) screen, with steel centralizers. Malcolm used a crane to install the 8-inch I.D. casing and screen after the borehole was completed to 120.4 feet bgs. The inside of the permanent 30-inch I.D. surface casing and the borehole annulus below the surface casing were filled with CalPortland Product 8700 (4x8) filter sand. A vertical observation pipe consisting of threaded, 2-inch I.D., PVC blank casing and machine-slotted screen (0.020-inch slots) was placed in the same borehole as the 8-inch I.D. casing and secured to the steel centralizers. Well construction details are presented on the boring logs in (Figures A-2 through A-5) and in Table A-1. Details of the VWP installations are presented in Table A-2. See Appendix C for further groundwater-related discussions. TABLE A-1 SUMMARY OF WELL INSTALLATION DETAILS SHANNON & WILSON, INC. 21-1-22082-003-R1f-TA-1/wp/lk 21-1-22082-003 Boring and Well No. Ecology Tag No. Well Installation Date Approx. Ground Surface Elevation1 (feet) Open Monument Stickup Above Grade1,2 (feet) Approx. Open Monument Rim Elevation1,2 (feet) Borehole Diameter2 (inches) Diameter and Casing Material2 (inches) Casing Stickdown Below Monument2 (feet) Approx. Casing Rim Elevation1,2 (feet) Filter Type Top of Filter Depth2 (feet) Bottom of Filter Depth2 (feet) Screen Slot Size (Inches) Screen Top Depth2 (feet) Screen Bottom Depth2 (feet) Screen Length2 (feet) Casing Depth Below Casing Rim1 (feet) Approx. Well Bottom Elevation1,2 (feet) Sump Length2 (feet) IW-1 BJZ 272 4/21/2016 444.9 2.65 447.6 10.5 6; PVC 0.56 447.0 No. 10-20 59.2 91.2 385.7 -353.7 0.020 63.3 90.4 381.6 -354.5 27.1 93.0 354.1 0.45 IW-2 None 10/6/2016 444.4 0.30 444.7 24 8; Stainless Steel3 0.93 443.8 No. 4-8 2.0 120.4 442.4 -324.0 0.020 28.3 119.7 416.1 -324.7 91.4 120.3 323.5 0.58 OW-1 BJZ 265 4/7/2016 445.1 3.04 448.2 6.0 2; PVC 0.38 447.8 No. 10-20 170.0 185.5 275.1 -259.6 0.020 175.4 185.0 269.8 -260.1 9.7 188.0 259.7 0.34 OW-2 BJX 262 8/19/2016 444.7 0.00 444.7 6.0 2; PVC 0.83 443.8 No. 10-20 174.8 184.0 269.9 -260.7 0.020 179.2 183.9 265.4 -260.8 4.6 184.1 259.8 0.20 Notes: 1 Elevations based on client electronic survey file dated October 13, 2016, and on differential levels shot with reference to well OW-2 at north end of running track. The reference vertical datum is North American Vertical Datum of 1988 (NAVD 88). Well OW-1 was developed on April 12, 2016, using a check valve-type inertial pump equipped with a surge block (Waterra); approximately 68 gallons of water were removed. Well OW-2 was developed on August 24, 2016, using a check valve-type inertial pump equipped with a surge block (Waterra); approximately 37 gallons of water were removed. Approx. = Approximate Ecology = Washington State Department of Ecology No. = Number Approx. Filter Pack Elevation Range1,2 (feet) Approx. Screen Elevation Range1,2 (feet) 2 Value shown was based on hand measurements during well construction. Unless otherwise noted, depths are referenced to ground surface. 3 At IW-2, a permanent surface casing (30-inch-diameter steel) was installed to 60.5 feet deep and cemented in place. The top of the 8-inch screen was extended up inside the 30-inch surface casing, and the interior of the 30-inch casing was filled with filter material. A 2-inch polyvinyl chloride (PVC) observation pipe was also installed at IW-2 within the 30-inch surface casing to 120.4 feet deep, screened from 60.3 - 120.2 feet deep with a 0.2-foot sump. TABLE A-2 SUMMARY OF VIBRATING WIRE PIEZOMETER INSTALLATION DETAILS SHANNON & WILSON, INC. 21-1-22082-003-R1f-TA-2/wp/lk 21-1-22082-003 Boring and VWP No.1 Ecology Tag VWP Installation Date Approx. Ground Surface and Monument Elevation2 (feet) VWP Depth Below Ground Surface3 (feet) Approx. VWP Elevation2, 3 (feet) Top of Filter Pack Depth3 (feet) Bottom of Filter Pack Depth3 (feet) Serial No. Pressure Range (psi) Linear Gage Factor (psi/digit) Thermal Factor (psi/o Celsius) Field Saturated Zero Reading (digits) Field Initial Temperature (o Celsius) OW-2, VWP1 BJX 262 8/19/2016 444.7 66.3 378.4 64.2 68.5 380.5 -376.2 1624163 50 -0.01636 -0.01331 8930.3 20.7 OW-2, VWP2 BJX 262 8/19/2016 444.7 146.3 298.4 140.8 146.3 303.9 -298.4 1624739 100 -0.02383 -0.002972 8879.9 20.9 Notes: 3 Value shown was based on hand measurements during VWP construction. 4 Instrument is Geokon Model 4500S. o Celsius = degrees Celcius / = per Approx. = approximate Ecology = Washington State Department of Ecology No. = Number Instrument Information4 psi = pounds per square inch 1 VWP = vibrating wire piezometer Approx. Filter Pack Elevation Range2,3 (feet) 2 Based on electronic client file provided on October 20, 2016. The reference vertical datum is the North American Vertical Datum of 1988. November 2016 21-1-22082-003 Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington 1Gravel, sand, and fines estimated by mass. Other constituents, such as organics, cobbles, and boulders, estimated by volume. 2Reprinted, with permission, from ASTM D2488 - 09a Standard Practice for Description and Identification of Soils (Visual-Manual Procedure), copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard may be obtained from ASTM International, www.astm.org. 140 pounds with a 30-inch free fall. Rope on 6- to 10-inch-diam. cathead 2-1/4 rope turns, > 100 rpm NOTE: If automatic hammers are used, blow counts shown on boring logs should be adjusted to account for efficiency of hammer. 10 to 30 inches long Shoe I.D. = 1.375 inches Barrel I.D. = 1.5 inches Barrel O.D. = 2 inches Sum blow counts for second and third 6-inch increments. Refusal: 50 blows for 6 inches or less; 10 blows for 0 inches. RELATIVE CONSISTENCY N, SPT, BLOWS/FT.5% to 12% fine-grained: with Silt or with Clay 3 15% or more of a second coarse- grained constituent: with Sand or with Gravel 5 < 5% 5 to 10% 15 to 25% 30 to 45% 50 to 100% Surface Cement Seal Asphalt or Cap Slough Inclinometer or Non-perforated Casing Vibrating Wire Piezometer N, SPT, BLOWS/FT. < 4 4 - 10 10 - 30 30 - 50 > 50 DESCRIPTION < #200 (0.075 mm = 0.003 in.) #200 to #40 (0.075 to 0.4 mm; 0.003 to 0.02 in.) #40 to #10 (0.4 to 2 mm; 0.02 to 0.08 in.) #10 to #4 (2 to 4.75 mm; 0.08 to 0.187 in.) SIEVE NUMBER AND/OR APPROXIMATE SIZE #4 to 3/4 in. (4.75 to 19 mm; 0.187 to 0.75 in.) 3/4 to 3 in. (19 to 76 mm) 3 to 12 in. (76 to 305 mm) > 12 in. (305 mm) Fine Coarse Fine Medium Coarse BOULDERS COBBLES GRAVEL FINES SAND Sheet 1 of 3 CONSTITUENT2 SOIL DESCRIPTION AND LOG KEY SHANNON & WILSON, INC. Geotechnical and Environmental Consultants Absence of moisture, dusty, dry to the touch Damp but no visible water Visible free water, from below water table FIG. A-1 Shannon & Wilson, Inc. (S&W), uses a soil identification system modified from the Unified Soil Classification System (USCS). Elements of the USCS and other definitions are provided on this and the following pages. Soil descriptions are based on visual-manual procedures (ASTM D2488) and laboratory testing procedures (ASTM D2487), if performed. STANDARD PENETRATION TEST (SPT) SPECIFICATIONS Hammer: Sampler: N-Value: Dry Moist Wet MOISTURE CONTENT TERMS Modifying (Secondary) Precedes major constituent Major Minor Follows major constituent 1All percentages are by weight of total specimen passing a 3-inch sieve.2The order of terms is: Modifying Major with Minor.3Determined based on behavior.4Determined based on which constituent comprises a larger percentage.5Whichever is the lesser constituent. COARSE-GRAINED SOILS (less than 50% fines)1 NOTE: Penetration resistances (N-values) shown on boring logs are as recorded in the field and have not been corrected for hammer efficiency, overburden, or other factors. PARTICLE SIZE DEFINITIONS RELATIVE DENSITY / CONSISTENCY Sand or Gravel 4 30% or more coarse-grained: Sandy or Gravelly 4 More than 12% fine-grained: Silty or Clayey 3 15% to 30% coarse-grained: with Sand or with Gravel 4 30% or more total coarse-grained and lesser coarse- grained constituent is 15% or more: with Sand or with Gravel 5 Very soft Soft Medium stiff Stiff Very stiff Hard Very loose Loose Medium dense Dense Very dense RELATIVE DENSITY FINE-GRAINED SOILS (50% or more fines)1 COHESIVE SOILS < 2 2 - 4 4 - 8 8 - 15 15 - 30 > 30 COHESIONLESS SOILS Silt, Lean Clay, Elastic Silt, or Fat Clay 3 PERCENTAGES TERMS 1, 2 Trace Few Little Some Mostly WELL AND BACKFILL SYMBOLS Bentonite Cement Grout Bentonite Grout Bentonite Chips Silica Sand Perforated or Screened Casing S&W INORGANIC SOIL CONSTITUENT DEFINITIONS SO I L _ C L A S S _ K E Y _ P G 1 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 3 / 1 6 November 2016 21-1-22082-003 Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington GC SC Inorganic Organic (more than 50% of coarse fraction retained on No. 4 sieve) MAJOR DIVISIONS GROUP/GRAPHICSYMBOL CH OH ML CL TYPICAL IDENTIFICATIONS Gravel Sand Silty Sand; Silty Sand with Gravel Clayey Sand; Clayey Sand with Gravel Clayey Gravel; Clayey Gravel with Sand Sheet 2 of 3 Gravels Primarily organic matter, dark incolor, and organic odor SW (more than 12% fines) Silts and Clays Silts and Clays (more than 50% retained on No. 200 sieve) (50% or more of coarse fraction passes the No. 4 sieve) (liquid limit less than 50) (liquid limit 50 or more) Organic Inorganic FINE-GRAINEDSOILS SM Sands Silty or ClayeyGravel Silt; Silt with Sand or Gravel; Sandy or Gravelly Silt Organic Silt or Clay; Organic Silt or Clay with Sand or Gravel; Sandy or Gravelly Organic Silt or Clay HIGHLY-ORGANICSOILS COARSE-GRAINEDSOILS OL (less than 5% fines) GW Geotechnical and Environmental ConsultantsSHANNON & WILSON, INC. (less than 5% fines) PT FIG. A-1 (more than 12% fines) MH SP GP GM Silty orClayey Sand Silty Gravel; Silty Gravel with Sand (50% or more passes the No. 200 sieve) SOIL DESCRIPTION AND LOG KEY Elastic Silt; Elastic Silt with Sand or Gravel; Sandy or Gravelly Elastic Silt Fat Clay; Fat Clay with Sand or Gravel; Sandy or Gravelly Fat Clay Organic Silt or Clay; Organic Silt or Clay with Sand or Gravel; Sandy or Gravelly Organic Silt or Clay Poorly Graded Sand; Poorly Graded Sand with Gravel Well-Graded Sand; Well-Graded Sand with Gravel Well-Graded Gravel; Well-Graded Gravel with Sand Poorly Graded Gravel; Poorly Graded Gravel with Sand Lean Clay; Lean Clay with Sand or Gravel; Sandy or Gravelly Lean Clay NOTES 1. Dual symbols (symbols separated by a hyphen, i.e., SP-SM, Sand with Silt) are used for soils with between 5% and 12% fines or when the liquid limit and plasticity index values plot in the CL-ML area of the plasticity chart. Graphics shown on the logs for these soil types are a combination of the two graphic symbols (e.g., SP and SM). 2. Borderline symbols (symbols separated by a slash, i.e., CL/ML, Lean Clay to Silt; SP-SM/SM, Sand with Silt to Silty Sand) indicate that the soil properties are close to the defining boundary between two groups. Peat or other highly organic soils (see ASTM D4427) SO I L _ C L A S S _ K E Y _ P G 2 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 3 / 1 6 NOTE: No. 4 size = 4.75 mm = 0.187 in.; No. 200 size = 0.075 mm = 0.003 in. UNIFIED SOIL CLASSIFICATION SYSTEM (USCS) (Modified From USACE Tech Memo 3-357, ASTM D2487, and ASTM D2488) November 2016 21-1-22082-003 Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington SHANNON & WILSON, INC. Geotechnical and Environmental Consultants FIG. A-1 Sheet 3 of 3 SOIL DESCRIPTION AND LOG KEY 1Reprinted, with permission, from ASTM D2488 - 09a Standard Practice for Description and Identification of Soils (Visual-Manual Procedure), copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard may be obtained from ASTM International, www.astm.org. 2Adapted, with permission, from ASTM D2488 - 09a Standard Practice for Description and Identification of Soils (Visual-Manual Procedure), copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard may be obtained from ASTM International, www.astm.org. Interbedded Laminated Fissured Slickensided Blocky Lensed Homogeneous ATD Diam. Elev. ft. FeO gal. Horiz. HSA I.D. in. lbs. MgO mm MnO NA NP O.D. OW pcf PID PMT ppm psi PVC rpm SPT USCS qu VWP Vert. WOH WOR Wt. Crumbles or breaks with handling or slight finger pressure. Crumbles or breaks with considerable finger pressure. Will not crumble or break with finger pressure. PLASTICITY2 CEMENTATION TERMS1 GRADATION TERMS STRUCTURE TERMS1 ACRONYMS AND ABBREVIATIONS Alternating layers of varying material or color with layers at least 1/4-inch thick; singular: bed. Alternating layers of varying material or color with layers less than 1/4-inch thick; singular: lamination. Breaks along definite planes or fractures with little resistance. Fracture planes appear polished or glossy; sometimes striated. Cohesive soil that can be broken down into small angular lumps that resist further breakdown. Inclusion of small pockets of different soils, such as small lenses of sand scattered through a mass of clay. Same color and appearance throughout. Narrow range of grain sizes present or, within the range of grain sizes present, one or more sizes are missing (Gap Graded). Meets criteria in ASTM D2487, if tested. Full range and even distribution of grain sizes present. Meets criteria in ASTM D2487, if tested. Poorly Graded Well-Graded Weak Moderate Strong Irregular patches of different colors. Soil disturbance or mixing by plants or animals. Nonsorted sediment; sand and gravel in silt and/or clay matrix. Material brought to surface by drilling. Material that caved from sides of borehole. Disturbed texture, mix of strengths. VISUAL-MANUAL CRITERIA A 1/8-in. thread cannot be rolled at any water content. A thread can barely be rolled and a lump cannot be formed when drier than the plastic limit. A thread is easy to roll and not much time is required to reach the plastic limit. The thread cannot be rerolled after reaching the plastic limit. A lump crumbles when drier than the plastic limit. It takes considerable time rolling and kneading to reach the plastic limit. A thread can be rerolled several times after reaching the plastic limit. A lump can be formed without crumbling when drier than the plastic limit. Sharp edges and unpolished planar surfaces. Similar to angular, but with rounded edges. Nearly planar sides with well-rounded edges. Smoothly curved sides with no edges. Width/thickness ratio > 3. Length/width ratio > 3. PARTICLE ANGULARITY AND SHAPE TERMS1 ADDITIONAL TERMS Angular Subangular Subrounded Rounded Flat Elongated DESCRIPTION Nonplastic Low Medium High At Time of Drilling Diameter Elevation Feet Iron Oxide Gallons Horizontal Hollow Stem Auger Inside Diameter Inches Pounds Magnesium Oxide Millimeter Manganese Oxide Not Applicable or Not Available Nonplastic Outside Diameter Observation Well Pounds per Cubic Foot Photo-Ionization Detector Pressuremeter Test Parts per Million Pounds per Square Inch Polyvinyl Chloride Rotations per Minute Standard Penetration Test Unified Soil Classification System Unconfined Compressive Strength Vibrating Wire Piezometer Vertical Weight of Hammer Weight of Rods Weight Mottled Bioturbated Diamict Cuttings Slough Sheared APPROX. PLASITICITY INDEX RANGE < 4 4 to 10 10 to 20 > 20 SO I L _ C L A S S _ K E Y _ P G 3 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 3 / 1 6 9.0 14.0 Gray-brown, Silty Sand with Gravel (SM); moist; fine, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict. Fill/Ablation Till/Weathered Till (Hf/Qvat/Qvt) - Hand-excavated to 1 foot. Standing water about 1 foot below IW-1 grade in adjacent swale. Gray-brown, Silty Sand with Gravel (SM); wet; fine, subrounded to subangular gravel; fine to coarse sand; diamict pockets. Weathered Till (Qvt) - Perched groundwater at about 11 feet during well installation on 4/21/2016. Gray-brown to gray, Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict. Till (Qvt) - Iron oxide staining from 14 to 18 feet. R1 R2 Du r i n g D r i l l i n g De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 2 4 6 8 10 12 14 16 18 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : K J W Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 10.5 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE IW-1 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. Terrasonic FIG. A-2SHANNON & WILSON, INC. 91.2 ft. ~ 444.92 ft. NAVD 88 Sheet 1 of 5 Re v : E A S November 2016 21-1-22082-003 Ty p : L K Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 28.0 38.0 - Gray from 20 to 25 feet. Gray to gray-brown, Silty Sand with Gravel and Cobbles (SM) to Silty Gravel with Sand (GM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; few subrounded cobbles; nonplastic fines; diamict pockets. Till-Like Deposits/Till (Qvd/Qvt) - Iron oxide staining from 31 to 32 feet. Gray-brown, Silty Sand with Gravel and Cobbles (SM) to Silty Gravel with Sand and Cobbles (GM); moist; fine, subrounded to R3 R4 R5 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 22 24 26 28 30 32 34 36 38 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : K J W Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 10.5 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE IW-1 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. Terrasonic FIG. A-2SHANNON & WILSON, INC. 91.2 ft. ~ 444.92 ft. NAVD 88 Sheet 2 of 5 Re v : E A S November 2016 21-1-22082-003 Ty p : L K Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 45.0 48.0 57.5 subangular gravel; fine to coarse sand; trace to few subrounded cobbles; nonplastic fines; diamict pockets. Till-Like Deposits/Advance Outwash (Qvd/Qva) - Added water at 40 feet. Gray-brown, Silty Sand (SM); moist to wet; fine, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict pockets. Till-Like Deposits/Advance Outwash (Qvd/Qva) Gray-brown, Poorly Graded Sand with Silt and Gravel (SP-SM) to Silty Sand with Gravel (SM); wet; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; few silty sand pockets. Advance Outwash/Till-Like Deposits (Qva/Qvd) Gray, Silty Sand with Gravel (SM); moist; fine, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict. Till-Like Deposits (Qvd) R6 R7 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 42 44 46 48 50 52 54 56 58 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : K J W Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 10.5 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE IW-1 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. Terrasonic FIG. A-2SHANNON & WILSON, INC. 91.2 ft. ~ 444.92 ft. NAVD 88 Sheet 3 of 5 Re v : E A S November 2016 21-1-22082-003 Ty p : L K Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 61.0 79.0 Dr y ( 1 1 / 5 / 2 0 1 6 ) Gray-brown, Poorly Graded Sand with Gravel (SP), Poorly Graded Sand (SP), and Poorly Graded Sand with Silt (SP-SM); moist; fine, subrounded to subangular gravel; fine to coarse sand; nonplastic fines. Advance Outwash (Qva) - Pockets of silty sand at 69 to 69.5 feet. - Layer of silty sand at 78 to 78.5 feet. Gray-brown, Poorly Graded Sand (SP) to Poorly Graded Sand with Silt (SP-SM); moist; R8 R9 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 62 64 66 68 70 72 74 76 78 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : K J W Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 10.5 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE IW-1 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. Terrasonic FIG. A-2SHANNON & WILSON, INC. 91.2 ft. ~ 444.92 ft. NAVD 88 Sheet 4 of 5 Re v : E A S November 2016 21-1-22082-003 Ty p : L K Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 91.2 fine to medium sand; trace subrounded gravel; nonplastic fines. Advance Outwash (Qva) - Last sample on 4/19/2016 was to 80 feet; hole was cased to 70 feet. Dry to bottom of open hole (80 feet) at start of day on 4/20/2016. - Trace cobbles below 87.5 feet. BOTTOM OF BORING COMPLETED 04/20/2016 NOTE: Well installed on 4/21/2016. Bottom of sump cap was perforated with 5 small holes for drainage; approximately 1 inch of sediment accumulated in the sump during 4/25/2016 injection test, plugging the drain holes. R1 0 R1 1 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 82 84 86 88 90 92 94 96 98 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : K J W Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 10.5 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE IW-1 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. Terrasonic FIG. A-2SHANNON & WILSON, INC. 91.2 ft. ~ 444.92 ft. NAVD 88 Sheet 5 of 5 Re v : E A S November 2016 21-1-22082-003 Ty p : L K Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 6.0 10.0 Brown to gray-brown, Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; (contact depth based on adjacent explorations). Fill (Hf) - Top 10 feet of surface seal is temporary and will be replaced when project moves to construction. Brown to gray-brown, Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict pockets. Ablation Till/Weathered Till (Qvat/Qvt) Gray-brown to gray, Silty Sand with Gravel and Cobbles (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict. Till (Qvt) De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 2 4 6 8 10 12 14 16 18 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : P V H Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 24 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF BORING IW-2 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Grab Sample Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Bucket Auger Malcolm Drilling Bauer BG-24 39-in. (1-m.) hole from 0 to 61 ft. FIG. A-3SHANNON & WILSON, INC. 120.4 ft. ~ 444.41 ft. NAVD 88 Sheet 1 of 7 Re v : J K P November 2016 21-1-22082-003 Ty p : L K N Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 37.0 - Seepage from about 23 to 26 feet, with trace boulders to 15-inch-diameter. Gray, Silty Sand with Gravel and Cobbles (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict; (more dense and less sand than above). Du r i n g D r i l l i n g De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 22 24 26 28 30 32 34 36 38 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : P V H Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 24 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF BORING IW-2 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Grab Sample Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Bucket Auger Malcolm Drilling Bauer BG-24 39-in. (1-m.) hole from 0 to 61 ft. FIG. A-3SHANNON & WILSON, INC. 120.4 ft. ~ 444.41 ft. NAVD 88 Sheet 2 of 7 Re v : J K P November 2016 21-1-22082-003 Ty p : L K N Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 47.0 49.0 55.0 1 2 3 4 5 Till (Qvt) Gray-brown, Silty Sand with Gravel (SM); wet; fine to coarse, subrounded to subangular gravel; fine to coarse sand; low plasticity fines; diamict pockets. Till-Like Deposits (Qvd) Gray-brown, Poorly Graded Sand with Silt (SP-SM); wet; trace to few, fine to coarse, rounded to subrounded gravel; fine to coarse sand; seepage and caving during open-hole drilling. Advance Outwash (Qva) - With cobbles from about 52 to 54 feet. - Drilled open hole from 0 to 54 feet; caved to 52 feet after auger pass from 51 to 54 feet; set 1 m. casing to 61 feet to control caving. Brown-gray, Silty Gravel with Sand (GM); wet; fine to coarse, subangular to subrounded gravel; fine to coarse sand; nonplastic to low plasticity fines; diamict pockets. Till-Like Deposits/Advance Outwash (Qvd/Qva) De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 42 44 46 48 50 52 54 56 58 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : P V H Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 24 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF BORING IW-2 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Grab Sample Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Bucket Auger Malcolm Drilling Bauer BG-24 39-in. (1-m.) hole from 0 to 61 ft. FIG. A-3SHANNON & WILSON, INC. 120.4 ft. ~ 444.41 ft. NAVD 88 Sheet 3 of 7 Re v : J K P November 2016 21-1-22082-003 Ty p : L K N Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 60.0 61.0 6 7 8 9 Brown, Clayey Gravel with Sand (GC); wet; fine to coarse, subangular to subrounded gravel; fine to coarse sand; medium plasticity fines; diamict pockets. Till-Like Deposits (Qvd) Gray-brown, Poorly Graded Sand with Gravel (SP); moist; trace silt; little, fine to coarse, rounded to subrounded gravel; fine to coarse sand; nonplastic fines. Advance Outwash (Qva) - Drilled 24-inch pilot hole from 61 to 91 feet. Temporarily backfilled with cuttings from 62 to 91 feet. Placed bentonite chip seal from 59.5 to 62 feet. Installed permanent 30-inch steel surface casing to 60.5 feet. Temporarily filled 30-inch casing with additional spoils to 30 feet deep, and grouted 30-inch casing in place. Grout intruded up through spoils to about 44 feet deep inside 30-inch casing. - Interbedded with poorly graded sand with silt and gravel from about 72 to 74 feet. De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 62 64 66 68 70 72 74 76 78 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : P V H Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 24 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF BORING IW-2 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Grab Sample Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Bucket Auger Malcolm Drilling Bauer BG-24 39-in. (1-m.) hole from 0 to 61 ft. FIG. A-3SHANNON & WILSON, INC. 120.4 ft. ~ 444.41 ft. NAVD 88 Sheet 4 of 7 Re v : J K P November 2016 21-1-22082-003 Ty p : L K N Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 86.0 98.0 10 11 12 13 14 Dr y ( 1 1 / 5 / 2 0 1 6 ) - Trace to little gravel and trace mica below about 80 feet. - Pocket (~6-inch) of black, organic silt at about 81 feet. Gray-brown, Poorly Graded Sand with Gravel (SP) to Poorly Graded Sand with Silt and Gravel (SP-SM); moist; little, fine to coarse, rounded to subrounded gravel; fine to coarse sand; nonplastic fines; trace mica. Advance Outwash (Qva) - On 10/6/2016, continued drilling with 24-inch auger, removing cuttings from 30-inch casing and then continuing to bottom of hole (120.4 feet). Drilled open hole below 60.5 feet. - Trace cobbles below about 92 feet. Gray-brown, Poorly Graded Sand with Gravel (SP); moist; some, fine to coarse, rounded to subrounded gravel; fine to coarse sand; De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 82 84 86 88 90 92 94 96 98 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : P V H Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 24 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF BORING IW-2 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Grab Sample Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Bucket Auger Malcolm Drilling Bauer BG-24 39-in. (1-m.) hole from 0 to 61 ft. FIG. A-3SHANNON & WILSON, INC. 120.4 ft. ~ 444.41 ft. NAVD 88 Sheet 5 of 7 Re v : J K P November 2016 21-1-22082-003 Ty p : L K N Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 101.0 15 16 17 18 nonplastic fines. Advance Outwash (Qva) - Caved during open-hole drilling. Gray-brown, Well Graded Sand with Silt and Gravel (SW-SM) to Well Graded Sand with Silt (SW-SM); moist; few to little fine to coarse, rounded to subrounded gravel; fine to coarse sand; nonplastic fines; trace seams of silty sand; trace mica. Advance Outwash (Qva) - Switched from solid stem auger to bucket auger at 101.5 feet to reduce caving. - Trace organics at about 105 feet. De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 102 104 106 108 110 112 114 116 118 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : P V H Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 24 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF BORING IW-2 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Grab Sample Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Bucket Auger Malcolm Drilling Bauer BG-24 39-in. (1-m.) hole from 0 to 61 ft. FIG. A-3SHANNON & WILSON, INC. 120.4 ft. ~ 444.41 ft. NAVD 88 Sheet 6 of 7 Re v : J K P November 2016 21-1-22082-003 Ty p : L K N Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 120.4BOTTOM OF BORING COMPLETED 10/6/2016 NOTE: Well casing and screen: 8-inch threaded 304 stainless steel, with 4 centralizers on about 30-foot centers. Surface casing: 30-inch steel to 60.5 feet deep. Well screen (0.020-inch continuous-slot) from approximately 28.3 feet deep (top is inside 30-inch surface casing) to 119.7 feet deep, with 0.6-foot sump. 24-inch borehole and interior of 30-inch casing filter-packed with 4x8 sand. Observation pipe (2-inch Schedule 40 PVC) installed in filter pack adjacent to 8-inch casing and screen, with 0.020-inch machine-slotted screen from approximately 60.3 to 120.2 feet deep, and a 0.2-foot sump. Approximately 1.2 feet of sediment accumulated in the 8" sump and screen during the 10/11-10/12/2016 injection test. De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 122 124 126 128 130 132 134 136 138 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : P V H Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 24 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF BORING IW-2 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES 20 40 Grab Sample Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Bucket Auger Malcolm Drilling Bauer BG-24 39-in. (1-m.) hole from 0 to 61 ft. FIG. A-3SHANNON & WILSON, INC. 120.4 ft. ~ 444.41 ft. NAVD 88 Sheet 7 of 7 Re v : J K P November 2016 21-1-22082-003 Ty p : L K N Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 10.0 19.0 Gray-brown, Silty Sand with Gravel (SM); moist; subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict pockets; few poorly graded sand pockets. Fill/Ablation Till/Weathered Till (Hf/Qvat/Qvt) - Hand-excavated to 2 feet. Standing water about 1 foot below OW-1 grade in adjacent swale. - Wet pocket at about 5.5 feet. - Wet below about 8.5 feet. Gray-brown, Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict. Till/Till-Like Deposits (Qvt/Qvd) Gray, Silty Sand with Gravel and Cobbles (SM) to Silty Gravel with Sand and Cobbles R1 R2 Du r i n g D r i l l i n g De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 2 4 6 8 10 12 14 16 18 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : K J W Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-1 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. Terrasonic 7-in. hole from 0 to 20 ft. FIG. A-4SHANNON & WILSON, INC. 185.5 ft. ~ 445.11 ft. NAVD 88 Sheet 1 of 10 Re v : E A S November 2016 21-1-22082-003 Ty p : L K Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 39.0 (GM); moist; trace to few subrounded cobbles; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict. Till (Qvt) - Bottom of temporary 7-inch casing set at 20 feet. - Gray-brown to gray below 25 feet. Gray-brown, Silty Sand with Gravel (SM) to Silty Gravel with Sand (GM); moist; fine to R3 R4 R5 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 22 24 26 28 30 32 34 36 38 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : K J W Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-1 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. Terrasonic 7-in. hole from 0 to 20 ft. FIG. A-4SHANNON & WILSON, INC. 185.5 ft. ~ 445.11 ft. NAVD 88 Sheet 2 of 10 Re v : E A S November 2016 21-1-22082-003 Ty p : L K Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 50.0 55.5 coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict. Till-Like Deposits/Till (Qvd/Qvt) - Drilled tight and sticky from 40 to 50 feet. - Stopped on 4/4/2016 after sampling to 50 feet. Added water during cleanout run from 40 to 50 feet, prior to sample run 7. Gray-brown, Silty Sand with Gravel (SM) to Silty Gravel with Sand (GM); moist to wet; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict pockets. Advance Outwash/Till-Like Deposits (Qva/Qvd) - Moist below 53 feet. Gray, Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict pockets; easier drilling than above. Till-Like Deposit/Advance Outwash (Qvd/Qva) R6 R7 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 42 44 46 48 50 52 54 56 58 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : K J W Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-1 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. Terrasonic 7-in. hole from 0 to 20 ft. FIG. A-4SHANNON & WILSON, INC. 185.5 ft. ~ 445.11 ft. NAVD 88 Sheet 3 of 10 Re v : E A S November 2016 21-1-22082-003 Ty p : L K Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 60.0 65.0 68.5 70.0 72.5 Gray-brown, Poorly Graded Sand with Silt (SP-SM); moist; few fine to coarse, subrounded to subangular gravel; fine to medium sand; nonplastic fines. Advance Outwash (Qva) - Layer of poorly graded gravel with sand from 62.1 to 62.5 feet. - Layer of silty sand with gravel from 62.5 to 63 feet. Gray-brown, Poorly Graded Sand with Gravel and Cobbles (SP); moist; trace subrounded cobbles; fine to coarse, subrounded to subangular gravel; fine to coarse sand; trace nonplastic fines. Advance Outwash (Qva) Gray-brown, Poorly Graded Sand (SP) to Silty Sand (SM); moist; few fine, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; few diamict pockets. Advance Outwash (Qva) Gray-brown, Poorly Graded Gravel with Silt, Sand, and Cobbles (GP-GM); moist; trace subangular cobbles; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines. Advance Outwash (Qva) Gray-brown, Poorly Graded Sand with Silt and Gravel (SP-SM) to Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; fines content may be elevated due to drilling method. Advance Outwash (Qva) - Hard drilling 77 to 80 feet. - Added water during cleanout run at 70 to 80 feet, prior to sample run 10. R8 R9 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 62 64 66 68 70 72 74 76 78 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : K J W Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-1 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. Terrasonic 7-in. hole from 0 to 20 ft. FIG. A-4SHANNON & WILSON, INC. 185.5 ft. ~ 445.11 ft. NAVD 88 Sheet 4 of 10 Re v : E A S November 2016 21-1-22082-003 Ty p : L K Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 80.0 86.7 93.5 96.0 98.5 Gray-brown, Poorly Graded Sand with Silt and Gravel (SP-SM) to Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines. Advance Outwash (Qva) Gray-brown, Poorly Graded Sand with Gravel (SP) to Poorly Graded Gravel with Sand (GP); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines. Advance Outwash (Qva) - Added water during cleanout run from 80 to 90 feet, prior to sample run 11. Gray-brown, Poorly Graded Sand with Silt, Gravel, and Cobbles (SP-SM) to Silty Sand with Gravel and Cobbles (SM); moist; trace subangular cobbles; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines. Advance Outwash (Qva) Gray-brown, Poorly Graded Sand with Gravel (SP); moist; fine subrounded to subangular gravel; fine to coarse sand; trace nonplastic fines. Advance Outwash (Qva) R1 0 R1 1 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 82 84 86 88 90 92 94 96 98 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : K J W Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-1 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. Terrasonic 7-in. hole from 0 to 20 ft. FIG. A-4SHANNON & WILSON, INC. 185.5 ft. ~ 445.11 ft. NAVD 88 Sheet 5 of 10 Re v : E A S November 2016 21-1-22082-003 Ty p : L K Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 100.0 105.0 107.5 112.5 Gray-brown, Silty Sand with Gravel and Cobbles (SM); moist; trace subrounded cobbles; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines. Advance Outwash (Qva) Gray-brown, Poorly Graded Sand with Silt and Gravel (SP-SM) to Poorly Graded Sand (SP); moist; fine subrounded to subangular gravel; fine to coarse sand; nonplastic fines. Advance Outwash (Qva) - Layer of silty sand from 101 to 101.3 feet. Gray-brown, Poorly Graded Sand with Gravel (SP) to Poorly Graded Sand with Silt and Gravel (SP-SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines. Advance Outwash (Qva) Gray-brown, Poorly Graded Sand with Silt and Gravel (SP-SM) to Silty Sand (SM); moist; trace to few, fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; fines content may be elevated due to drilling method. Advance Outwash (Qva) - Added water during cleanout run from 100 to 110 feet and during extraction of sample run 13. Gray-brown, Poorly Graded Sand with Silt and Gravel (SP-SM) to Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; few silty sand pockets. Advance Outwash (Qva) R1 2 R1 3 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 102 104 106 108 110 112 114 116 118 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : K J W Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-1 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. Terrasonic 7-in. hole from 0 to 20 ft. FIG. A-4SHANNON & WILSON, INC. 185.5 ft. ~ 445.11 ft. NAVD 88 Sheet 6 of 10 Re v : E A S November 2016 21-1-22082-003 Ty p : L K Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 122.0 123.0 130.0 134.3 136.5 138.5 - Tried adding second 10-foot core barrel so could sample and clean out at same time. Coring hard and slow. Added water during extraction of sample run 14. Gray-brown, Poorly Graded Sand with Silt and Gravel (SP-SM); moist; fine to coarse, subrounded to subangular gravel; fine to medium sand; nonplastic fines. Advance Outwash (Qva) Gray-brown, Poorly Graded Sand with Silt (SP-SM) to Poorly Graded Sand (SP); moist; trace to few fine, subrounded to subangular gravel; fine to medium sand; nonplastic fines; few silty sand pockets from 123 to 125 feet. Advance Outwash (Qva) - Added water during cleanout run from 120 to 130 feet and during extraction of sample run 15. Gray-brown, Poorly Graded Sand with Silt (SP-SM) to Silty Sand (SM); moist; trace subangular, fine gravel; fine to medium sand; nonplastic fines; few silty sand clasts. Advance Outwash (Qva) - Last sample on 4/5/2016 was to 140 feet; hole was cased to 130 feet. Possible perched water measured at 132.5 feet at start of day on 4/6/2016 (hole had caved to 133.5 feet). Gray-brown, Silty Sand (SM); wet; trace fine, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; slight diamict texture. Advance Outwash (Qva) Gray-brown, Silty Sand (SM) to Poorly Graded Sand with Silt (SP-SM); moist; trace fine, R1 4 R1 5 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 122 124 126 128 130 132 134 136 138 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : K J W Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-1 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. Terrasonic 7-in. hole from 0 to 20 ft. FIG. A-4SHANNON & WILSON, INC. 185.5 ft. ~ 445.11 ft. NAVD 88 Sheet 7 of 10 Re v : E A S November 2016 21-1-22082-003 Ty p : L K Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 143.0 145.0 146.8 148.0 150.0 151.8 157.0 subrounded to subangular gravel; fine to coarse sand; nonplastic fines; few silty sand clasts. Advance Outwash (Qva) Gray-brown, Poorly Graded Sand with Silt (SP-SM) to Poorly Graded Sand (SP); trace fine, subrounded to subangular gravel; fine to medium sand; nonplastic fines. Advance Outwash (Qva) Gray-brown, Poorly Graded Sand with Silt and Gravel (SP-SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines. Advance Outwash (Qva) Gray-brown, Poorly Graded Sand with Silt (SP-SM); moist; fine to medium sand; nonplastic fines. Advance Outwash (Qva) Gray-brown, Silty Sand (SM); moist; fine sand; nonplastic fines. Advance Outwash (Qva) Gray-brown to gray, Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; fines content may be elevated due to drilling method. Advance Outwash (Qva) Gray-brown, Poorly Graded Sand with Silt and Gravel (SP-SM) to Poorly Graded Sand with Gravel (SP); moist; fine subrounded to subangular gravel; fine to medium sand; nonplastic fines. Advance Outwash (Qva) Gray-brown, Poorly Graded Sand with Silt (SP-SM) to Poorly Graded Sand (SP); moist; trace to few fine, subrounded to subangular R1 6 R1 7 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 142 144 146 148 150 152 154 156 158 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : K J W Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-1 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. Terrasonic 7-in. hole from 0 to 20 ft. FIG. A-4SHANNON & WILSON, INC. 185.5 ft. ~ 445.11 ft. NAVD 88 Sheet 8 of 10 Re v : E A S November 2016 21-1-22082-003 Ty p : L K Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 160.0 165.0 170.5 172.4 177.0 179.0 11 / 5 / 2 0 1 6 gravel; fine to medium sand; nonplastic fines; few silty sand pockets. Advance Outwash (Qva) Gray to gray-brown, Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; fines content may be elevated due to drilling method. Advance Outwash (Qva) Gray-brown, Poorly Graded Sand (SP) to Poorly Graded Sand with Silt (SP-SM); moist; fine to medium sand; trace nonplastic fines. Advance Outwash (Qva) - Layers and seams of silty sand at 162 to 162.5, 163 feet, and 164.7 to 165 feet. Gray-brown, Poorly Graded Sand with Silt (SP-SM) to Poorly Graded Sand (SP) ; moist to wet; trace fine, subrounded to subangular gravel; fine to medium sand; nonplastic fines. Advance Outwash (Qva) - Layer of silty, fine sand from 167.3 to 167.7 feet. - Layer of poorly graded sand with silt and gravel from 169 to 169.5 feet. Gray-brown, Silty Sand with Gravel (SM); wet; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines. Advance Outwash (Qva) - Diamict layer of silty sand with gravel at 172 feet. Gray-brown, Poorly Graded Sand with Silt (SP-SM) to Poorly Graded Sand (SP); wet; few fine, subrounded to subangular gravel; fine to medium sand; nonplastic fines. Advance Outwash (Qva) R1 8 R1 9 R2 0 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 162 164 166 168 170 172 174 176 178 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : K J W Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-1 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. Terrasonic 7-in. hole from 0 to 20 ft. FIG. A-4SHANNON & WILSON, INC. 185.5 ft. ~ 445.11 ft. NAVD 88 Sheet 9 of 10 Re v : E A S November 2016 21-1-22082-003 Ty p : L K Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 185.5 - Pockets of silty sand with gravel from 173.5 to 175 feet. - Seam of silty sand with gravel at 176.3 feet. Brown, Poorly Graded Sand with Silt and Gravel (SP-SM) to Silty Sand with Gravel (SM); wet; fine to coarse, subrounded to subangular gravel; fine to medium sand; nonplastic fines; trace organics and mica. Advance Outwash (Qva) - Last sample was to 179 feet on 4/6/2016; casing was at 168.5 feet. Caved to 168 feet by start of day 4/7/2016; water level 166.5 feet. Added water during cleanout run prior to sample run 21. Brown, Poorly Graded Sand with Silt and Gravel (SP-SM), Poorly Graded Sand (SP), and Poorly Graded Gravel with Sand (GP); wet; fine to coarse, rounded to subangular gravel; fine to coarse sand; trace to few nonplastic fines. Advance Outwash (Qva) - Heaved 10 feet during retrieval of sample run 21. Cased to 185 feet and added water to wash out heave to 185.5 feet, prior to well installation. BOTTOM OF BORING COMPLETED 4/7/2016 NOTE: Well installed on 4/7/2016. R2 1 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 182 184 186 188 190 192 194 196 198 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : K J W Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-1 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. Terrasonic 7-in. hole from 0 to 20 ft. FIG. A-4SHANNON & WILSON, INC. 185.5 ft. ~ 445.11 ft. NAVD 88 Sheet 10 of 10 Re v : E A S November 2016 21-1-22082-003 Ty p : L K Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 0.4 1.5 5.5 8.0 25.0 Grass and Topsoil Fill (Hf) Brown, Silty Sand with Gravel (SM); moist; fine, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; trace organics. Fill (Hf) Gray-brown, Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict. Fill (Hf) - With pockets of organics below 5 feet. Brown to red-brown, Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic to low plasticity fines; diamict. Ablation Till/Weathered Till (Qvat/Qvt) Gray-brown, Silty Sand with Gravel (SM) to Silty Gravel with Sand (GM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict. Weathered Till/Till/Till-Like Deposits (Qvt/Qvd) - With scattered wet seams below 12 feet. Gray, Silty Sand with Gravel and Cobbles (SM) to Silty Gravel with Sand and Cobbles (GM); moist; trace subrounded cobbles; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict. Till (Qvt) R- 1 R- 2 R- 3 R- 4 Du r i n g D r i l l i n g De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 5 10 15 20 25 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : E A S Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-2 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in VWP Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. TerraSonic 7-in. hole from 0 to 50 ft. FIG. A-5SHANNON & WILSON, INC. 190 ft. ~ 444.67 ft. NAVD 88 Sheet 1 of 7 Re v : P V H November 2016 21-1-22082-003 Ty p : L K N Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 45.5 50.0 - Brown to gray-brown from 30 to 31 feet. - Wet from approximately 35 to 35.5 feet. Gray-brown, Silty Sand with Gravel (SM); wet; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict pockets. Till-Like Deposits (Qvd/Qva) - Advanced below 50 feet with 6-inch casing. Gray-brown, Poorly Graded Sand with Silt and Gravel (SP-SM) to Poorly Graded Gravel with Silt and Sand (GP-GM); wet; fine to coarse, subrounded to angular gravel; fine to coarse sand; nonplastic fines. Advance Outwash/Till-Like Deposits (Qva/Qvd) R- 5 R- 6 R- 7 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 35 40 45 50 55 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : E A S Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-2 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in VWP Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. TerraSonic 7-in. hole from 0 to 50 ft. FIG. A-5SHANNON & WILSON, INC. 190 ft. ~ 444.67 ft. NAVD 88 Sheet 2 of 7 Re v : P V H November 2016 21-1-22082-003 Ty p : L K N Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 70.0 72.0 73.5 76.0 Dr y ( 1 1 / 5 / 2 0 1 6 ) - Moist below about 60 feet. - Diamict layer of silty sand with gravel from 64.5 to 65 feet. - Diamict layer of silty sand with gravel from 67.5 to 68.3 feet. Gray-brown, Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict pockets. Advance Outwash/Till-Like Deposits (Qva/Qvd) Gray-brown, Silty Sand (SM); moist; trace fine, subrounded to subangular gravel; fine to medium sand; nonplastic fines. Advance Outwash (Qva) Gray-brown, Silty Gravel with Sand (GM) to Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines. Advance Outwash/Till-Like Deposits (Qva/Qvd) Brown to gray-brown, Poorly Graded Sand with Silt (SP-SM) to Silty Sand (SM); moist; few fine, subrounded to angular gravel; fine to coarse sand; nonplastic fines; fines content may be elevated due to drilling method. Advance Outwash (Qva) R- 8 R- 9 R- 1 0 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 65 70 75 80 85 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : E A S Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-2 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in VWP Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. TerraSonic 7-in. hole from 0 to 50 ft. FIG. A-5SHANNON & WILSON, INC. 190 ft. ~ 444.67 ft. NAVD 88 Sheet 3 of 7 Re v : P V H November 2016 21-1-22082-003 Ty p : L K N Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 90.0 100.0 111.5 Gray-brown, Poorly Graded Sand with Silt and Gravel (SP-SM) to Silty Sand with Gravel (SM); trace to little, fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; fines content may be elevated due to drilling method. Advance Outwash (Qva) Gray-brown, Well Graded Sand with Silt and Gravel (SW-SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; few silty sand seams; fines content may be elevated due to drilling method. Advance Outwash (Qva) - With layers of poorly graded sand with silt below 109 feet. Gray-brown, Well Graded Sand with Silt, Gravel, and Cobbles (SW-SM); moist; trace subrounded cobbles; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; fines content may be elevated due to drilling method. Advance Outwash (Qva) - Layer of poorly graded sand with silt and gravel from approximately 118.3 to 119 feet. R- 1 1 R- 1 2 R- 1 3 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 95 100 105 110 115 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : E A S Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-2 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in VWP Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. TerraSonic 7-in. hole from 0 to 50 ft. FIG. A-5SHANNON & WILSON, INC. 190 ft. ~ 444.67 ft. NAVD 88 Sheet 4 of 7 Re v : P V H November 2016 21-1-22082-003 Ty p : L K N Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 126.0 130.0 142.0 145.5 Dr y ( 1 1 / 5 / 2 0 1 6 ) - Sampled to 126 feet and cased to 110 feet on 8/17/2016. No recovery from 121 to 126 feet (sample fell out of core barrel). Hole was open and dry to 118 feet on morning of 8/18/2016. - Added water prior to sample run 15 to assist with sample retrieval. Gray-brown, Poorly Graded Sand with Silt (SP-SM) to Silty Sand (SM); moist; few fine, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; few poorly graded sand with silt seams; fines content may be elevated due to drilling method. Advance Outwash (Qva) Gray-brown, Poorly Graded Sand with Silt (SP-SM) to Silty Sand (SM); moist; trace to few, fine to coarse, subrounded to subangular gravel; fine to medium sand; nonplastic fines. Advance Outwash (Qva) - Layer of silty sand at 136.5 to 137 feet. Gray-brown, Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to medium sand; nonplastic fines; fines content may be elevated due to drilling method. Advance Outwash (Qva) Gray, Silty Sand (SM); moist; few fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; few baked, silty, fine sand clasts; fines content may be R- 1 4 R- 1 5 R- 1 6 R- 1 7 R- 1 8 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 125 130 135 140 145 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : E A S Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-2 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in VWP Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. TerraSonic 7-in. hole from 0 to 50 ft. FIG. A-5SHANNON & WILSON, INC. 190 ft. ~ 444.67 ft. NAVD 88 Sheet 5 of 7 Re v : P V H November 2016 21-1-22082-003 Ty p : L K N Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 150.0 152.0 156.5 160.0 172.5 11 / 5 / 2 0 1 6 elevated due to drilling method. Advance Outwash (Qva) - Increased silt below 147 feet. - Added water prior to sample run 19. Gray-brown, Silty Sand with Gravel (SM); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines; diamict; fines content may be elevated due to drilling method. Till-Like Deposits/Advance Outwash (Qvd/Qva) Gray-brown, Poorly Graded Gravel with Silt and Sand (GP-GM) to Poorly Graded Gravel with Sand (GP); moist; fine to coarse, subrounded to subangular gravel; fine to coarse sand; nonplastic fines. Advance Outwash (Qva) Gray, Silty Sand with Gravel (SM); wet; fine, subrounded to subangular gravel; fine to coarse sand; nonplastic fines (possibly baked during drilling); few diamict clasts; trace silt seams; fines content may be elevated due to drilling method. Advance Outwash/Till-Like Deposits (Qva/Qvd) Gray-brown, Poorly Graded Sand with Silt (SP-SM) to Silty Sand (SM); moist; few fine to coarse, subrounded to subangular gravel; fine to medium sand; nonplastic fines; few sandy silt seams; trace mica. Advance Outwash (Qva) - Saturated below about 169 feet, and drilled hard/tight from 170 to 172 feet. Gray-brown, Poorly Graded Sand with Silt (SP-SM) to Poorly Graded Sand (SP); wet; trace to few fine gravel; nonplastic fines; fine R- 1 9 R- 2 0 R- 2 1 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 155 160 165 170 175 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : E A S Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-2 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES CONTINUED NEXT SHEET 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in VWP Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. TerraSonic 7-in. hole from 0 to 50 ft. FIG. A-5SHANNON & WILSON, INC. 190 ft. ~ 444.67 ft. NAVD 88 Sheet 6 of 7 Re v : P V H November 2016 21-1-22082-003 Ty p : L K N Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 180.0 190.0 to coarse sand; trace mica. Advance Outwash (Qva) - Layer of silty, fine to medium sand (SM) from 175.5 to 176 feet. - Cased to 180 feet before sample run 22. Gray-brown, Poorly Graded Sand (SP); wet; nonplastic fines; fine to coarse sand (trace to few coarse sand); no to trace fine to coarse, subrounded gravel; trace mica. Advance Outwash (Qva) - Heaved to 172 feet after sample run 22. Cased to 185 feet and washed out heave prior to well installation. BOTTOM OF BORING COMPLETED 8/19/2016 NOTE: Well installed on 8/19/2016. R- 2 2 De p t h , f t . Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington De p t h , f t . 185 190 195 200 205 Well Screen and Sand Filter Drilling Method: Drilling Company: Drill Rig Equipment: Other Comments: Lo g : E A S Northing: Easting: Station: Offset: SOIL DESCRIPTION 20 40 60 Sa m p l e s 6 in. N/A N/A Refer to the report text for a proper understanding of the subsurface materials and drilling methods. The stratification lines indicated below represent the approximate boundaries between material types, and the transition may be gradual. * LOG OF SONIC CORE OW-2 0 60 0 Total Depth: Top Elevation: Vert. Datum: Horiz. Datum: Ground Water Level ATD Gr o u n d Wa t e r NOTES 20 40 Soil Core (as in Sonic Core Borings) Bentonite Chips/Pellets Bentonite Grout Hole Diam.: Rod Diam.: Hammer Type: LEGEND Sy m b o l Ground Water Level in VWP Ground Water Level in Well 1. Refer to KEY for explanation of symbols, codes, abbreviations and definitions. 2. Groundwater level, if indicated above, is for the date specified and may vary. 3. USCS designation is based on visual-manual classification and selected lab testing. Sonic Core Holt Services Inc. TerraSonic 7-in. hole from 0 to 50 ft. FIG. A-5SHANNON & WILSON, INC. 190 ft. ~ 444.67 ft. NAVD 88 Sheet 7 of 7 Re v : P V H November 2016 21-1-22082-003 Ty p : L K N Geotechnical and Environmental Consultants Sample Not Recovered Bentonite-Cement Grout REV 3 - Approved for Submittal MA S T E R _ L O G _ E 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 1 / 2 2 / 1 6 % Water Content % Fines (<0.075mm) 21-1-22082-003 APPENDIX B GEOTECHNICAL LABORATORY TESTING 21-1-22082-003-R1f-AB/wp/lk 21-1-22082-003 B-i APPENDIX B GEOTECHNICAL LABORATORY TESTING TABLE OF CONTENTS Page B.1 VISUAL CLASSIFICATION .........................................................................................B-1 B.2 WATER CONTENT DETERMINATION ......................................................................B-1 B.3 GRAIN SIZE DISTRIBUTION ANALYSIS ..................................................................B-1 B.4 CONSIDERATIONS .......................................................................................................B-2 B.5 REFERENCES ................................................................................................................B-2 TABLES Laboratory Terms Sample Types Laboratory Test Summary TESTS Grain Size Distribution Plot, Boring IW-2 Grain Size Distribution Plot, Boring OW-1 Grain Size Distribution Plot, Boring OW-2 21-1-22082-003-R1f-AB/wp/lk 21-1-22082-003 B-1 APPENDIX B GEOTECHNICAL LABORATORY TESTING We performed geotechnical laboratory testing on selected soil samples retrieved from the three borings completed for the New Madrona K-8 Project’s Geotechnical Report. The laboratory testing program included tests to classify the soil and provide data for hydrogeologic studies related to underground injection control well feasibility and design. We performed visual classification on retrieved samples. Our laboratory testing program included water content determinations and grain size distribution analyses. The following sections describe the laboratory test procedures. B.1 VISUAL CLASSIFICATION We visually classified soil samples retrieved from the borings using a system based on ASTM International (ASTM) D2487-11, Standard Test Method for Classification of Soil for Engineering Purposes (ASTM, 2011), and ASTM D2488-09a, Standard Recommended Practice for Description of Soils (Visual-manual Procedure) (ASTM, 2009). Appendix A summarizes our classification system. We assigned a Unified Soil Classification System (USCS) group name and symbol, based on our visual classification of particles finer than 76.2 millimeters (3 inches). We revised visual classifications using results of the index tests discussed below. B.2 WATER CONTENT DETERMINATION We tested the water content of selected samples in accordance with ASTM D2216-10, Standard Method for Laboratory Determination of Water (Moisture) Content of Soil, Rock, and Soil- aggregate Mixtures (ASTM, 2010). Comparison of the water content of a soil with its index properties can be useful in characterizing soil unit weight, consistency, compressibility, and strength. The tables in Appendix B and boring logs in Appendix A include the water content test results. B.3 GRAIN SIZE DISTRIBUTION ANALYSIS Grain size distribution analyses separate soil particles through mechanical or sedimentation processes. Grain size distributions are used to classify the granular component of soils and can correlate with soil properties, including frost susceptibility, permeability, shear strength, liquefaction potential, capillary action, and sensitivity to moisture. Appendix B includes grain size distribution analysis results in graphical format. Grain size distribution plots provide tabular 21-1-22082-003-R1f-AB/wp/lk 21-1-22082-003 B-2 information about each specimen, including: USCS group symbol and group name, water content, constituent (i.e., cobble, gravel, sand, and fines) percentages, coefficients of uniformity and curvature, if applicable, personnel initials, ASTM standard designation, and testing remarks. Constituent percentages are presented in the Laboratory Test Summary in this appendix and fines contents are plotted as data points in borings logs in Appendix A. Sieve Analysis: We performed mechanical sieve analyses on selected soil specimens to determine the grain size distribution of coarse-grained soil particles, in accordance with ASTM C136/C136M-14, Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates (ASTM, 2014). B.4 CONSIDERATIONS Drilling and sampling methodologies may affect the outcome of prescribed geotechnical laboratory tests. Refer to the field exploration discussion in this report for a discussion of these potential effects. Instances of limited recovery may have resulted in test samples not meeting specified minimum mass requirements, per ASTM standards. Test plots show which samples do not meet ASTM specified minimum mass requirements. B.5 REFERENCES ASTM International (ASTM), 2009, Standard practice for description and identification of soils (visual/manual procedure), D2488-09a: West Conshohocken, Pa., ASTM International, Annual book of standards, v. 04.08, soil and rock (I): D420 - D5876, 11 p., available: www.astm.org. ASTM International (ASTM), 2010, Standard test methods for laboratory determination of water (moisture) content of soil and rock by mass, D2216-10: West Conshohocken, Pa., ASTM International, Annual book of standards, v. 04.08, soil and rock (I): D420 - D5876, 7 p., available: www.astm.org. ASTM International (ASTM), 2011, Standard practice for classification of soils for engineering purposes (unified soil classification system), D2487-11: West Conshohocken, Pa., ASTM International, Annual book of standards, v. 04.08, soil and rock (I): D420 - D5876, 12 p., available: www.astm.org. ASTM International (ASTM), 2014, Standard test method for sieve analysis of fine and coarse aggregates, C136-14: West Conshohocken, Pa., ASTM International, Annual book of standards, v. 04.02, concrete and aggregates, 5 p., available: www.astm.org. LABORATORY TERMS SHANNON & WILSON, INC. 21-1-22082-003-R1-AB-Lab Tables-Terms and Test Summary/wp/lk 21-1-22082-003 Abbreviations, Symbols, and Terms Descriptions %Percent *Sample specimen weight did not meet required minimum mass for the test method ASTM Std.ASTM International Standard Cc Coefficient of curvature Clay-size Soil particles finer than 0.002 millimeter cm Centimeter cm2 Square centimeter Coarse-grained Soil particles coarser than 0.075 mm (cobble-, gravel- and sand-sized particles) Cobbles Soil particles finer than 305 mm and coarser than 76.2 mm Cu Coefficient of uniformity CU Consolidated Undrained ε Axial strain Fine-grained Soil particles finer than 0.075 mm (silt- and clay-sized particles) ft Feet γm Wet unit weight Gravel Soil particles finer than 76.2 mm and coarser than 4.75 mm Gs Specific gravity of soil solids Ho Initial height ∆H Change in height ∆Ηload End of load increment deformation in Inch in3 Cubic inch LL Liquid Limit min Minute mm Millimeter µm Micrometer MPa Mega-Pascal NP Non-plastic OC Organic content p Total stress p'Effective stress Pa Pascal pcf Pounds per cubic foot PI Plasticity Index PL Plastic Limit psf Pounds per square foot q Deviatoric stress Sand Soil particles finer than 4.75 mm and coarser than 0.075 mm sec Second Silt Soil particles finer than 0.075 mm and coarser than 0.002 mm tn Time to n% primary consolidation tload Duration of load increment tsf Short tons per square foot USCS Unified Soil Classification System UU Unconsolidated-Undrained WC Water content SAMPLE TYPES SHANNON & WILSON, INC. 21-1-22082-003-R1-AB-Lab Tables-Terms and Test Summary/wp/lk 21-1-22082-003 Abbreviations, Symbols, and Terms Descriptions 2SS 2.5" O.D. Split Spoon Sample 2ST 2" O.D. Thin-Walled Tube 3HSA 3" CME HSA Sampler 3SS 3" O.D. Split Spoon Sample 4SS Soil particles finer than 0.002 millimeter 6SS 6" I.D. Split Spoon Sample CA_MC Modified California Sampler CA_SPT Standard Penetration Test (SPT) CORE Rock Core DM + 3.25" O.D. Split Spoon Sample DMR 3.25" Sampler With Internal Rings GRAB Grab Sample GUS 3.0" O.D. GUS Sample OSTER 3.0" O.D. Osterberg Sample PITCHER 3" O.D. Pitcher Sample PMT Pressuremeter Test (f=failed) PO Porter Penetration Test Sample PT 2.5" O.D. Thin-Walled Tube ROCK Rock Core Sample SCORE Soil Core (as in Sonic Core Borings) SH1 1" Plastic Sheath SH2 2" Plastic Sheath with Soil Recovery SH3 2" Plastic Sheath with no Soil Recovery SPT 2.0" O.D. Split Spoon Sample SS Split Spoon ST 3" O.D. Thin-Walled Tube STW 3" O.D. Thin-Walled Tube TEST Sample Test Interval TR TR Test TW Thin Wall Sample UNDIST Undisturbed Sample VANE Vane Shear WATER Water sample for Probe Logs XCORE Core Sample LABORATORY TEST SUMMARY SHANNON & WILSON, INC. 21-1-22082-003-R1-AB-Lab Tables-Terms and Test Summary/wp/lk 21-1-22082-003 Boring Top Depth (feet)Sa m p l e N u m b e r Sa m p l e T y p e USCS WC (%)% G r a v e l % S a n d % F i n e s Cu Cc Soil Description IW-2 91 S-12 GRAB SP 7.3 17*78*4.3*4.0 0.8 Poorly Graded Sand with Gravel IW-2 98 S-14 GRAB SP 3.3 37*62*0.8*8.5 0.5 Poorly Graded Sand with Gravel IW-2 111 S-16 GRAB SW-SM 5.1 21*71*8.6*7.9 1.3 Well-graded Sand with Silt and Gravel IW-2 119 S-18 GRAB SW-SM 5.0 11 81 8.7 6.3 1.4 Well-graded Sand with Silt OW-1 Soil particles finer than 0.002 millimeter R-7 SCORE SM 5.2 22 56 22 Silty Sand with Gravel OW-1 63.5 R-8 SCORE SP-SM 4.8 7*84*9.5*4.8 2.2 Poorly Graded Sand with Silt OW-1 87.5 R-10 SCORE SP 9.1 34*61*4.5*17.9 0.4 Poorly Graded Sand with Gravel OW-1 108 R-11 SCORE SM 4.7 7*74*19*Silty Sand OW-1 125 R-14 SCORE SP-SM 6.5 2 90 8.1 3.8 1.6 Poorly Graded Sand with Silt OW-1 135 R-15 SCORE SM 9.2 4*70*26*Silty Sand OW-1 153 R-17 SCORE SP-SM 5.0 4*88*8*4.1 1.5 Poorly Graded Sand with Silt OW-1 182 R-21 SCORE SP-SM 18.6 7 88 5.1 2.3 1.2 Poorly Graded Sand with Silt OW-2 12 R-2 SCORE 10.8 OW-2 56 R-7 SCORE SP-SM 10.4 19*74*7.3*5.6 0.8 Poorly Graded Sand with Silt and Gravel OW-2 72 R-9 SCORE SP-SM 15.2 2*89*9*4.2 1.7 Poorly Graded Sand with Silt OW-2 82 R-10 SCORE SM 6.3 5*78*16*Silty Sand OW-2 91.5 R-11 SCORE SM 8.8 12*68*20*Silty Sand OW-2 107 R-12 SCORE SW-SM 3.8 26*62*12*Well-graded Sand with Silt and Gravel OW-2 128 R-15 SCORE SM 4.7 14*70*16*Silty Sand OW-2 137.5 R-17 SCORE SP-SM 4.3 5*88*7.4*3.1 2.6 Poorly Graded Sand with Silt OW-2 151.5 R-19 SCORE SM 6.2 10*56*34*Silty Sand OW-2 154 R-19 SCORE SP-SM 1.8 36*58*5.2*15.3 0.5 Poorly Graded Sand with Silt and Gravel OW-2 182.5 R-22 SCORE SP 15.1 10*87*2.8*3.0 1.0 Poorly Graded Sand 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 4.7 5 8 Depth (ft) Sample Identification 91.0 98.0 111.0 119.0 Fines % Tested ByllGravel % Sand % AKV AKV SAB AKV 7.3 3.3 5.1 5.0 4.3 0.8 8.6 8.7 78 62 71 81 17 37 21 11 Fine Mesh Opening in Inches Grain Size in Millimeters Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington GRAIN SIZE DISTRIBUTION PLOT SiltCoarse Mesh Openings per Inch, U.S. Standard 2 10 0.0 6 0.0 4 0.0 0 3 0.0 0 1 0.0 0 2 0.0 0 3 0.0 0 8 0.0 1 0.0 7 50.10.2136204060 76. 2 Grain Size (mm) Pe r c e n t C o a r s e r b y M a s s 1 1/2 3/8 4 20 USCSGroupSymbol SP SP SW-SM SW-SM 3 100 100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 Poorly Graded Sand with Gravel Poorly Graded Sand with Gravel Well-Graded Sand with Silt and Gravel Well-Graded Sand with Silt USCS Group Name C136 C136 C136 C136 0.0 0 1 0.0 0 4 0.0 0 6 0.0 4 0.0 60.3 0.0 2 0.0 3 FinesSand 2410 Pe r c e n t F i n e r b y M a s s 200 0.0 2 0.0 0 2 SHANNON & WILSON, INC. • 400 NORTH 34TH STREET • SUITE 100 • SEATTLE, WASHINGTON • 98103 • MAIN (206) 632-8020 • FAX (206) 695-6777 BORING IW-2 WC % 60 Review By ASTM Std. < 2um % < 20um % 0.6 40 30 0.4 Gravel Clay-SizeMediumFineCoarse 1 1 / 2 3/4 0.0 3 0.0 1 0.0 0 8 0.0 0 6 0.0 0 4 0.8 IW-2, S-12* IW-2, S-14* IW-2, S-16* IW-2, S-18 21 - 1 - 2 2 0 8 2 - 0 0 4 A _ G S A _ M A I N 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 0 / 2 8 / 1 6 * Test specimen did not meet minimum mass recommendations. 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 4.7 5 8 Depth (ft) Sample Identification 55.7 63.5 87.5 108.0 125.0 135.0 153.0 182.0 Fines % Tested ByllGravel % Sand % JFL JFL JFL JFL JFL JFL JFL JFL JCS AKV JCS JCS JCS JCS JCS JCS 5.2 4.8 9.1 4.7 6.5 9.2 5.0 18.6 22 9.5 4.5 19 8.1 26 8.0 5.1 56 84 61 74 90 70 88 88 22 7 34 7 2 4 4 7 Fine Mesh Opening in Inches Grain Size in Millimeters Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington GRAIN SIZE DISTRIBUTION PLOT SiltCoarse Mesh Openings per Inch, U.S. Standard 2 10 0.0 6 0.0 4 0.0 0 3 0.0 0 1 0.0 0 2 0.0 0 3 0.0 0 8 0.0 1 0.0 7 50.10.2136204060 76. 2 Grain Size (mm) Pe r c e n t C o a r s e r b y M a s s 1 1/2 3/8 4 20 USCSGroupSymbol SM SP-SM SP SM SP-SM SM SP-SM SP-SM 3 100 100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 Silty Sand with Gravel Poorly Graded Sand with Silt Poorly Graded Sand with Gravel Silty Sand Poorly Graded Sand with Silt Silty Sand Poorly Graded Sand with Silt Poorly Graded Sand with Silt USCS Group Name D422 C136 C136 C136 C136 C136 C136 C136 0.0 0 1 0.0 0 4 0.0 0 6 0.0 4 0.0 60.3 0.0 2 0.0 3 FinesSand 2410 Pe r c e n t F i n e r b y M a s s 200 0.0 2 0.0 0 2 SHANNON & WILSON, INC. • 400 NORTH 34TH STREET • SUITE 100 • SEATTLE, WASHINGTON • 98103 • MAIN (206) 632-8020 • FAX (206) 695-6777 BORING OW-1 WC % 60 Review By ASTM Std. < 2um % < 20um % 0.6 40 30 0.4 Gravel Clay-SizeMediumFineCoarse 1 1 / 2 3/4 0.0 3 0.0 1 0.0 0 8 0.0 0 6 0.0 0 4 0.8 OW-1, R-7 OW-1, R-8* OW-1, R-10* OW-1, R-11* OW-1, R-14 OW-1, R-15* OW-1, R-17* OW-1, R-21 21 - 1 - 2 2 0 8 2 - 0 0 4 A _ G S A _ M A I N 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 0 / 2 8 / 1 6 * Test specimen did not meet minimum mass recommendations. 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 4.7 5 8 Depth (ft) Sample Identification 56.0 72.0 82.0 91.5 107.0 128.0 137.5 151.5 154.0 182.5 Fines % Tested ByllGravel % Sand % JFL JFL JFL JFL JFL JFL JFL JFL JFL JFL AKV AKV AKV AKV AKV AKV AKV AKV AKV AKV 10.4 15.2 6.3 8.8 3.8 4.7 4.3 6.2 1.8 15.1 7.3 9.0 16 20 12 16 7.4 34 5.2 2.8 74 89 78 68 62 70 88 56 58 87 19 2 5 12 26 14 5 10 36 10 Fine Mesh Opening in Inches Grain Size in Millimeters Hydrogeologic Report New Madrona K-8 Project Edmonds, Washington GRAIN SIZE DISTRIBUTION PLOT SiltCoarse Mesh Openings per Inch, U.S. Standard 2 10 0.0 6 0.0 4 0.0 0 3 0.0 0 1 0.0 0 2 0.0 0 3 0.0 0 8 0.0 1 0.0 7 50.10.2136204060 76. 2 Grain Size (mm) Pe r c e n t C o a r s e r b y M a s s 1 1/2 3/8 4 20 USCSGroupSymbol SP-SM SP-SM SM SM SW-SM SM SP-SM SM SP-SM SP 3 100 100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 Poorly Graded Sand with Silt and Gravel Poorly Graded Sand with Silt Silty Sand Silty Sand Well-Graded Sand with Silt and Gravel Silty Sand Poorly Graded Sand with Silt Silty Sand Poorly Graded Sand with Silt and Gravel Poorly Graded Sand USCS Group Name C136 C136 C136 C136 C136 C136 C136 C136 C136 C136 0.0 0 1 0.0 0 4 0.0 0 6 0.0 4 0.0 60.3 0.0 2 0.0 3 FinesSand 2410 Pe r c e n t F i n e r b y M a s s 200 0.0 2 0.0 0 2 SHANNON & WILSON, INC. • 400 NORTH 34TH STREET • SUITE 100 • SEATTLE, WASHINGTON • 98103 • MAIN (206) 632-8020 • FAX (206) 695-6777 BORING OW-2 WC % 60 Review By ASTM Std. < 2um % < 20um % 0.6 40 30 0.4 Gravel Clay-SizeMediumFineCoarse 1 1 / 2 3/4 0.0 3 0.0 1 0.0 0 8 0.0 0 6 0.0 0 4 0.8 OW-2, R-7* OW-2, R-9* OW-2, R-10* OW-2, R-11* OW-2, R-12* OW-2, R-15* OW-2, R-17* OW-2, R-19* OW-2, R-19* OW-2, R-22* 21 - 1 - 2 2 0 8 2 - 0 0 4 A _ G S A _ M A I N 2 1 - 2 2 0 8 2 . G P J S H A N _ W I L . G D T 1 0 / 2 8 / 1 6 * Test specimen did not meet minimum mass recommendations. 21-1-22282-003 APPENDIX C HYDROGEOLOGIC DATA AND ANALYSES 21-1-22082-003-R1f-AC/wp/lk 21-1-22082-003 C-i APPENDIX C HYDROGOLOGIC DATA AND ANALYSES TABLE OF CONTENTS Page C.1 OBSERVATION WELL DEVELOPMENT ...................................................................C-1 C.2 OBSERVATION WELL SAMPLING ............................................................................C-1 C.3 OBSERVATION WELL SLUG TESTING ....................................................................C-2 C.4 GROUNDWATER LEVEL MONITORING ..................................................................C-3 C.4.1 Monitoring Wells and Instrumentation .............................................................C-3 C.4.2 Results ...............................................................................................................C-3 C.4.3 Local Groundwater Flow and Gradient .............................................................C-4 C.5 PILOT DRY WELL IW-1 FIELD TESTING .................................................................C-4 C.5.1 Test Procedure ...................................................................................................C-4 C.5.2 Results ...............................................................................................................C-5 C.6 FULL-SCALE DRY WELL IW-2 FIELD TESTING.....................................................C-5 C.6.1 Test Procedure ...................................................................................................C-5 C.6.2 Results ...............................................................................................................C-6 C.7 GRAIN SIZE-BASED HYDRAULIC CONDUCTIVITY (K) ESTIMATES ................C-6 C.8 REFERENCES ................................................................................................................C-7 TABLES C-1 Baseline OW-1 Groundwater Quality Data C-2 Summary of OW-1 Slug Test Analyses C-3 Summary of IW-1 and IW-2 Inflow Test Results C-4 Summary of Soil Analyses TABLE OF CONTENTS (cont.) 21-1-22082-003-R1f-AC/wp/lk 21-1-22082-003 C-ii FIGURES C-1 Slug Tests – Observation Well OW-1 C-2 Falling Head Slug Test 1 – Observation Well OW-1 C-3 Rising Head Slug Test 1 – Observation Well OW-1 C-4 Falling Head Slug Test 2 – Observation Well OW-1 C-5 Rising Head Slug Test 2 – Observation Well OW-1 C-6 Falling Head Slug Test 3 – Observation Well OW-1 C-7 Rising Head Slug Test 3 – Observation Well OW-1 C-8 Observation Well OW-1 Groundwater Depth with Precipitation Data C-9 Observation Well OW-1 Groundwater Depth with Barometric Pressure Data C-10 Observation Well OW-2 Groundwater Depth with Precipitation Data C-11 Observation Well OW-2 Groundwater Depth with Barometric Pressure Data C-12 Barometric Efficiency Estimate for Observation Well OW-1 C-13 Barometric Efficiency Estimate for Observation Well OW-2 C-14 Observation Well OW-1 Response to IW-1 Test C-15 OW-2 Observation Well and VWP2 Response to IW-2 Test LABORATORY REPORT Fremont Analytical, Inc. Report, Lab ID: 1604140, dated April 21, 2016 (29 pages) 21-1-22082-003-R1f-AC/wp/lk 21-1-22082-003 C-1 APPENDIX C HYDROGEOLOGIC DATA AND ANALYSES C.1 OBSERVATION WELL DEVELOPMENT We developed observation wells OW-1 and OW-2 on April 12 and August 24, 2016, respectively. We developed each well to remove sediment from the screened zone and filter pack and to improve hydraulic connection to the Vashon advance outwash (Qva) aquifer soils. We developed both wells using an inertial-style pump (Waterra) equipped with a clean, acetal combination surge block and check valve that was attached to high-density polyethylene tubing. We measured field parameters (pH, specific conductance, temperature, and turbidity) during development of OW-1 using a YSI model 556 multi-parameter meter and an HF Scientific, Inc. turbidity meter. We measured sediment content of the discharged water during development of OW-2. We surge-blocked the screened intervals, purging approximately 68 (OW-1) and 37 gallons (OW-2) during development. A smaller volume was purged from OW-2 due to its shorter screen length (4.6 versus 9.7 feet at OW-1). Measured field parameters stabilized during development, and the screens were cleared of sediment. C.2 OBSERVATION WELL SAMPLING On April 14, 2016, we collected a groundwater sample from observation well OW-1 to measure baseline groundwater quality in the regional Qva aquifer before performing infiltration testing. We sampled well OW-1 using the same equipment that we used during development, with the exception that a clean, stainless steel check valve was used instead of the Acetal combination surge block/check valve. We purged OW-1 before sampling and collected the groundwater sample after field parameters had stabilized. We purged approximately 12.5 gallons of water (about 4.5 well casing volumes) from well OW-1 prior to sample collection. We delivered the groundwater sample under chain-of-custody procedures to a subcontracted laboratory, Fremont Analytical in Seattle. The sample was tested for petroleum hydrocarbon- related constituents and primary and secondary drinking water parameters. Table C-1 presents the field parameters measured immediately before sample collection and a summary of the laboratory test results. Table C-1 also provides a comparison to Washington State groundwater quality standards. The laboratory data report is also presented in this appendix. In general, the OW-1 sample results indicate that the Qva aquifer groundwater quality onsite is good. An exception was the relatively high concentration of manganese, 344 parts per billion 21-1-22082-003-R1f-AC/wp/lk 21-1-22082-003 C-2 (ppb), which is almost seven times higher than the secondary (aesthetic) drinking water standard of 50 ppb. Manganese occurs naturally in soil and groundwater in the Puget Sound region. The extent to which manganese dissolves into groundwater depends on the amount of oxygen in the water and, to a lesser extent, upon the pH of the water. If the oxygen content of groundwater is low, manganese tends to dissolve more readily. The zone from which the OW-1 groundwater sample was collected contains scattered organics, the decomposition of which depletes the oxygen content of the groundwater. This may contribute to the relatively high groundwater manganese concentration. C.3 OBSERVATION WELL SLUG TESTING On April 14, 2016, we performed single-well field “slug” tests in observation well OW-1 to estimate the horizontal hydraulic conductivity (Kh) of the Qva aquifer. A slug test estimates the Kh of the saturated sediments immediately surrounding the screened zone of a well. The testing involved inducing a rapid change in water level in the well by introducing or removing a sealed, internally weighted, polyvinyl chloride (PVC) slug. Raising the water level was achieved by lowering the slug below the static water level to displace water within the well casing. This procedure is termed a “falling head test” because the water level falls with time back to the static level. Lowering the water level was achieved by quickly removing the slug from the well. This is termed a “rising head test” because the water level rises back to the static level after the slug is removed. We measured the water level recovery rate back to static using a data logging pressure transducer (Levelogger), supplemented by manual readings. Figure C-1 presents the slug test data for the three falling head and three rising head tests for well OW-1. We analyzed the slug test data using the method developed by Bouwer and Rice (1976), as modified by Bouwer (1989). We used the computer modeling software program AQTESOLV for Windows (HydroSOLVE, Inc., 2010) to plot and interpret the six test data sets. Figures C-2 through C-7 present the slug test interpretation plots and Table C-2 summarizes the slug test results. The Kh results range between 52 and 77 feet per day (feet/day), or 3.2 x 10-2 to 5.4 x 10-2 feet/minute; the average Kh is 55 feet/day (3.8 x 10-2 feet/minute). This range is towards the low end of the Kh estimated from grain size data for two Qva aquifer soil samples collected at 182 and 182.5 feet deep at OW-1 and OW-2, respectively (64 and 92 feet/day, Table C-4). 21-1-22082-003-R1f-AC/wp/lk 21-1-22082-003 C-3 C.4 GROUNDWATER LEVEL MONITORING C.4.1 Monitoring Wells and Instrumentation We have performed groundwater level monitoring in observation wells OW-1 and OW-2 since shortly after their installation. We deployed data logging transducers (Leveloggers) in wells OW-1 and OW-2 to collect frequent groundwater level data, and we installed a barometer (Barologger) in well OW-1 to collected barometric pressure data. The Leveloggers measure absolute pressure (atmospheric plus water pressure); we used the Barologger data to remove the atmospheric pressure contribution to the Levelogger readings. The data logging transducers continue to measure groundwater levels in wells OW-1 and OW-2. C.4.2 Results Figures C-8 through C-11 are groundwater level, barometric pressure, and local precipitation hydrographs for the period up to November 5, 2016. Figures C-9 and C-11 show that the groundwater levels in wells OW-1 and OW-2 responded to barometric pressure changes. We evaluated the barometric efficiencies of wells OW-1 and OW-2 by comparing well water level variations to changes in atmospheric pressure. We calculated the barometric efficiencies of wells OW-1 and OW-2 to be approximately 90 and 86 percent, respectively (Figures C-12 and C-13). This means that when the atmospheric pressure increases, the well water level decreases by a similar amount. Conversely, when the atmospheric pressure decreases, the well water level increases. During the April 12 to November 5, 2016, monitoring period, the measured groundwater level in well OW-1 ranged from 167.1 to 168.9 feet below grade, or Elevation 277.0 to 276.2 feet, representing a fluctuation range of about 1.8 feet (Figures C-8 and C-9). During the August 24 to November 5, 2016, monitoring period, the measured groundwater level in well OW-2 ranged from 167.3 to 168.9 feet below grade or Elevation 277.4 to 275.8 feet, representing a fluctuation range of about 1.6 feet (Figures C-10 and C-11). Two vibrating wire piezometers (VWPs) were installed in boring OW-2 at depths of approximately 66.3 (VWP1) and 146.3 feet (VWP2). The shallow VWP1 was dry throughout the monitoring period (August 24 to November 5, 2016). The deeper VWP2 was also dry during part of the monitoring period. However, VWP2 occasionally measured water about ½-inch above the sensor tip. In our experience, this is consistent of a VWP installed above the water table, and the occasional “wet” reading does not necessarily indicate the presence of perched 21-1-22082-003-R1f-AC/wp/lk 21-1-22082-003 C-4 groundwater. Alternatively, it may indicate a passing wetting front or the effects of varying barometric pressure on the VWP readings. We also collected occasional manual readings at dry wells IW-1 and IW-2. Both wells have been dry to date, except during and immediately following their respective inflow tests (see sections C.5 and C.6). Air blows audibly from the IW-1 and IW-2 well casings at times, in response to changing atmospheric pressure. These wells sometimes also develop slight suction, also in response to changing atmospheric pressure. C.4.3 Local Groundwater Flow and Gradient We estimated the local Qva aquifer gradient by comparing August 26, 2016, groundwater elevations measured at the project wells to the approximate groundwater elevation we measured during a previous study at City of Edmonds observation well A-2 (Shannon & Wilson, Inc., 2013). Observation well A-2 is located about 4,500 feet west of the site (Figure 4). The on-site groundwater elevations on August 26, 2016, were approximately 277.30 and 276.46 feet (OW-1 and OW-2, respectively). On October 2, 2012, the A-2 well groundwater elevation was approximately 259.46 feet, based on an approximate A-2 grade elevation of 315 feet. Based on these data, the Qva aquifer gradient beneath the project site is about 0.002 foot/foot to the west/northwest (Figure 4). C.5 PILOT DRY WELL IW-1 FIELD TESTING C.5.1 Test Procedure We performed an inflow test in pilot underground injection control (UIC) well IW-1 on April 25, 2016. This test consisted of directing water from a hydrant through a 2.5-inch-diameter fire hose and 2-inch-diameter PVC pipe into the dry well. We conducted the inflow testing for a period of 8.5 hours. We measured the inflow to the well using an inline flow meter. We measured the water level in IW-1 manually through a stilling pipe and by using Leveloggers installed at the well bottom. We also measured the groundwater level in OW-1 before, during, and after the IW-1 inflow test, both manually and using a Levelogger. We conducted the IW-1 inflow test as a series of steps, with each step representing a higher average flow rate into the well. We performed the first four inflow steps at approximately 14, 38, 72, and 103 gallons per minute (gpm); we maintained these inflow rates for approximately 1 hour each (Figure 7). However, these four steps did not run long enough for the water level to stabilize. The fifth step lasted for 4.3 hours. The fifth step’s inflow rate was more variable, initially reaching a maximum of approximately 126 gpm, which was sufficient to 21-1-22082-003-R1f-AC/wp/lk 21-1-22082-003 C-5 completely submerge the screened interval of the well. However, the flow rate from the hydrant began to fluctuate and drop off, possibly due to late afternoon increased domestic use of water at the adjacent apartment complex. The fifth step stabilized between 116 and 107 gpm, averaging 110 gpm over the last hour of the test. At this inflow rate, the IW-1 water level was approximately 67 feet below grade, or 4 feet below the top of the well screen, representing a head rise above the borehole bottom of 24 feet. C.5.2 Results We used the calculated OW-1 barometric efficiency to filter the OW-1 groundwater level data so that the OW-1 well response to the IW-1 inflow test could be analyzed (Figure C-14). Based on these data, the observed specific capacity of IW-1 is approximately 4.6 gpm/foot, and the Kh for the tested zone is 24 feet/day (1.7 x 10-2 feet/minute) (Table C-3). The groundwater level measured in well OW-1 did not immediately respond to the inflow test performed in IW-1. After adjusting the raw OW-1 groundwater level data for barometric efficiency, it was apparent that there was a slight antecedent rising trend in the OW-1 groundwater level during the test. This rising trend continued for a day after the IW-1 test and served to mask any effect of the IW-1 test on the groundwater level measured in OW-1. The OW-1 groundwater level rose again slightly (0.1 foot), starting about four days after the test and peaking six days after the test; in our opinion, this change is too small to definitely attribute to the inflow test. Based on these observations, the interbedded silty sand layers within the Qva unit (e.g., between about 134 and 160 feet deep) likely delayed the vertical infiltration of water into the Qva regional aquifer in the IW -1 test area. C.6 FULL-SCALE DRY WELL IW-2 FIELD TESTING C.6.1 Test Procedure We performed an inflow test in full-scale UIC well IW-2 on October 11 to 12, 2016 (Figure 8). This test consisted of directing water from a hydrant through a 2.5-inch-diameter fire hose and 2-inch-diameter PVC pipe into the dry well for 19 hours. We measured the inflow to the well using an inline flow meter. We measured the water level in IW-2 manually through the 2-inch-diameter observation pipe installed in the filter pack and electronically using Leveloggers installed at the bottom of the 2- and 8-inch-diameter casings. We also manually and electronically measured the groundwater level in wells OW-2 and OW-1 before, during, and after the IW-2 inflow test. We recorded VWP readings at OW-2 using data loggers during and after the inflow test period. 21-1-22082-003-R1f-AC/wp/lk 21-1-22082-003 C-6 C.6.2 Results We used OW-1 water levels measured during and after the IW-2 inflow test to filter out the effects of barometric pressure changes and other trends from the water levels measured at observation well OW-2 (Figure C-15). This enabled us to analyze the OW-2 well response to the IW-2 test. OW-2 is located approximately 14 feet from IW-2. Little change in groundwater level occurred in observation well OW-2 (an increase in water level of about 0.3-foot during the three days following the IW-2 test). The shallow VWP1 installed 66.3 feet below grade at OW-2 has remained dry to date. During and immediately after the IW-2 inflow test, water temporarily mounded at the interval measured by the deep VWP2 (installed at 146.3 feet deep at OW-2). This mound dissipated and VWP2 was dry again three and a half days after the end of the IW-2 test (Figure C-15). Based on these observations, the interbedded silty sand layers within the Qva (e.g., between about 147 and 160 feet deep) likely delay the vertical infiltration of water into the Qva regional aquifer in the IW-2 test area. C.7 GRAIN SIZE-BASED HYDRAULIC CONDUCTIVITY (K) ESTIMATES We performed grain size analyses (Appendix B) on selected soil samples from IW-2, OW-1, and OW-2. Table C-4 presents grain size-based estimated K values for selected soil samples, based on the Hazen (1893) approach.  The estimated K value for the tested till-like deposits (Qvd) sample from OW-1 (at 55.7 feet deep) was less than 0.01 foot/day.  The grain size-based K estimates for the 21 Qva unit samples range from 0.05 to 626 feet/day (3 x 10-5 to 0.43 feet/minute), which is a variation of over four orders of magnitude.  If the highest value is considered an outlier and is excluded, the arithmetic and geometric mean K values of the remaining 20 Qva samples are 38 and 11 feet/day (2.3 x 10-2 and 7.4 x 10-3 feet/minute), respectively. We suspect that the process of driving the sonic core barrel through unsaturated granular Qva soils resulted in some degree of sample pulverization, thereby increasing the fines content of some of the samples above their natural state. We have identified on the logs presented in Appendix A those sample cores where portions of the sample appeared dusty, indicating potential sample degradation due to the sampling process. We observed less apparent sample degradation in the larger diameter core samples collected at IW-1, as well as where samples were 21-1-22082-003-R1f-AC/wp/lk 21-1-22082-003 C-7 collected within saturated zones and where water was added during the drilling process. A comparison of sample grain size distributions for samples collected from auger boring IW-2 and those from similar depths collected from adjacent sonic core OW-2 indicates that the fines content of the auger samples was typically lower than that of the sonic core samples (Appendix B and Table C-4). C.8 REFERENCES Bouwer, Herman, 1989, The Bouwer and Rice slug test – an update: Ground Water, v. 27, no. 3, p. 304-309. Bouwer, Herman, and Rice, R.C., 1976. A slug test method for determining hydraulic conductivity of unconfined aquifers with completely or partially penetrating wells: Water Resources Research, v. 12, no. 3, p. 423-428. Hazen, A., 1893, Some physical properties of sands and gravels, with special reference to their use in filtration: Massachusetts State Board of Health 24th Annual Report, pub. doc. no. 34, p. 539-556. HydroSOLVE, Inc., 2010, AQTESOLV/Pro!, v. 4.50.002: Reston, Va., HydroSOLVE, Inc. Shannon & Wilson, Inc., 2013, Final infiltration study report, SW Edmonds basin study projects #1 and #3, Edmonds, Wash.: Report prepared by Shannon & Wilson, Inc., Seattle, Wash., 21-1-21768-001, for City of Edmonds, Edmonds, Wash., April 5. TABLE C-1 BASELINE OW-1 GROUNDWATER QUALITY DATA SHANNON & WILSON, INC. 21-1-22082-003-R1f-TC-1/wp/lk 21-1-22082-003 Constituent Method MCL per 173-200 WAC and 246-290 WAC MTCA Method A Cleanup Level per 173-340 WAC Sample No. OW-1- 041416 (Collected 4/14/2016) Field Parameters pH Field 6.5-8.5 7.1 Temperature (oC)Field 10.9 Specific Conductance (uS/cm)Field 700 330 Dissolved Oxygen (mg/L)Field 4.1 Turbidity (NTU)Field 1.5 Total Metals (ug/L) Antimony EPA Method 200.8 6 ND<0.2 Arsenic EPA Method 200.8 0.05 5 ND<1 Barium EPA Method 200.8 1,000 28.6 Beryllium EPA Method 200.8 4 ND<0.2 Cadmium EPA Method 200.8 5 5 ND<0.2 Chromium EPA Method 200.8 50 50 1.67 Copper EPA Method 200.8 1,000 ND<0.5 Iron EPA Method 200.8 300 ND<100 Lead EPA Method 200.8 AL=15 15 ND<1 Manganese EPA Method 200.8 50 344 Mercury EPA Mehod 245.1 2 2 ND<0.1 Nickel EPA Method 200.8 100 2.94 Selenium EPA Method 200.8 10 ND<1 Silver EPA Method 200.8 50 ND<0.2 Sodium EPA Method 200.8 RL=20,000 12,900 Thallium EPA Method 200.8 2 ND<0.2 Zinc EPA Method 200.8 5,000 27.3 Anions (mg/L) Chloride EPA Method 300.0 250 6.38 Cyanide, Total SM 4500-CN C, E 0.2 ND<0.05 Fluoride EPA Method 300.0 2 or 4 ND<0.1 Nitrite-N EPA Method 300.0 1 0.159 Nitrate-N EPA Method 300.0 10 1.01 Total Nitrate and Nitrite EPA Method 300.0 10 1.17 Ortho-phosphate EPA Method 300.0 ND<0.2 Sulfate EPA Method 300.0 250 22.6 Phosphorous, Total (as P)EPA Method 365.3 ND<0.2 Other Color (Color Units)SM 2120B 15 ND Total Dissolved Solids (mg/L)SM 2540C 500 182 Petroleum Hydrocarbons (ug/L) Diesel (Fuel Oil)NWTPH-Dx/Dx Ext.500 ND<50 Heavy Oil NWTPH-Dx/Dx Ext.500 ND<100 Gasoline NWTPH-Gx 1,000 ND<50 Volatile Organic Compounds (ug/L) Benzene EPA Method 8260C 1 5 ND<1 Toluene EPA Method 8260C 1,000 ND<1 Ethylbenzene EPA Method 8260C 700 ND<1 m,p-Xylene EPA Method 8260C ND<1 o-Xylene EPA Method 8260C ND<1 Notes: bold = constituent exceeded regulatory standard < = less than AL = action level established by the U.S. Environmental Protection Agency (EPA) for water distribution system C = Celsius cm = centimeters L = liter MCL = maximum contaminant level mg = milligrams MTCA = Model Toxics Control Act NTU = Nephelometric turbidity units NWTPH-Dx/Dx Ext. = Northwest Total Petroleum Hydrocarbons-Diesel/Diese-extended NWTPH-Gx = Northwest Total Petroleum Hydrocarbons-Gasoline ND = not detected RL = EPA-recommended level for those on a sodium-restrict diet SM = Standard Method ug = micrograms uS = microSiemens WAC = Washington Administrative Code 1,000 (Total Xylenes) TABLE C-2 SUMMARY OF OW-1 SLUG TEST ANALYSES SHANNON & WILSON, INC. 21-1-22082-003-R1f-TC-2/wp/lk 21-1-22082-003 feet/day cm/sec feet/min Falling Head Test 1 45 1.6E-02 3.2E-02 Rising Head Test 1 50 1.8E-02 3.5E-02 Falling Head Test 2 54 1.9E-02 3.7E-02 Rising Head Test 2 52 1.8E-02 3.6E-02 Falling Head Test 3 55 2.0E-02 3.8E-02 Rising Head Test 3 77 2.7E-02 5.4E-02 Geomean 55 1.9E-02 3.8E-02 Notes: bgs = below ground surface cm/sec = centimeters per second Kh = horizontal hydraulic conductivity Kv = vertical hydraulic conductivity min = minute Predominant Soil Type Screened By Well Interpreted Geologic Unit Tested OW-1 4/14/2016 168.3 SP-SM/SP Qva Observation Well Number Date Tested Test Number Static Water Level Depth (feet bgs) Hydraulic Conductivity (for Anisotropic Case, Kv/Kh=0.1) TABLE C-3 SUMMARY OF IW-1 AND IW-2 INFLOW TEST RESULTS SHANNON & WILSON, INC. 21-1-22082-003-R1f-TC-3/wp/lk 21-1-22082-003 Well Number Approximate Grade Elevation (feet NAVD 88) Dates Tested Discharge Rate1 (gpm) Discharge Rate1 (cu ft/day) Approximate Specific Capacity (gpm/foot) Top of Test Section Depth (feet) Bottom of Test Section Depth (feet) Approximate Test Section Top Elevation (feet) Approximate Test Section Bottom Elevation (feet) Test Section Length, L (feet) Water Column Height, H (feet) Borehole Radius, r (feet) Hydraulic Conductivity,2 K (feet/day) Hydraulic Conductivity,2 K (cm/sec) Hydraulic Conductivity,2 K (feet/min) Interpreted Geologic Unit Tested IW-1 444.9 4/25/2016 110 21174 4.6 67.4 91.2 377.5 353.7 23.8 23.8 0.44 24 8.4E-03 1.7E-02 Qva IW-2 444.4 10/11-10/12/2016 141 27141 6.7 99.3 120.4 345.1 324.0 21.1 21.1 1.00 30 1.0E-02 2.0E-02 Qva Notes: 1 Discharge to well (q) is the average measured over the last approximately one hour of the test period. 2 Equation for K estimation is from U.S. Department of the Interior, 1990. Procedure for constant head hydraulic conductivity tests in single drill holes, U.S. Bureau of Reclamation 7310-89, in Earth Manual, Part 2, 3rd ed. p. 1255, Equation 2 (for L > = 10r). L= Water Column Height (H), which is the approximately stabilized water height in the well above the total drilled depth. cm/sec = centimeters per second cu ft = cubic feet gpm = gallons per minute min = minute NAVD 88 = North American Vertical Datum of 1988 TABLE C-4 SUMMARY OF SOIL ANALYSES SHANNON & WILSON, INC. 21-1-22082-003-R1f-TC-4/wp/lk 21-1-22082-003 Approximate Cumulative Thickness of Soil Layers With Medium Treatment Capacity Between 120 feet and Deep Qva Aquifer Gravel %Sand %Fines %50%10%(feet/day)(cm/sec)(feet/min)(feet) IW-2 91 Auger 17 79 4.3 0.46 0.17 82 2.9E-02 5.7E-02 SP Low Qva IW-2 98 Auger 37 62 0.8 2.10 0.47 626 2.2E-01 4.3E-01 SP Low Qva IW-2 111 Auger 21 71 8.6 0.56 0.099 28 9.8E-03 1.9E-02 SW-SM Medium Qva IW-2 119 Auger 11 81 8.7 0.44 0.094 25 8.8E-03 1.7E-02 SW-SM Low Qva OW-1 55.7 Sonic Core 22 56 22 0.95 0.0015 Yes 0.0064 2.3E-06 4.4E-06 SM Medium Qvd OW-1 63.5 Sonic Core 7 84 9.5 0.33 0.080 18 6.4E-03 1.3E-02 SP-SM Medium Qva OW-1 87.5 Sonic Core 34 62 4.5 1.4 0.17 82 2.9E-02 5.7E-02 SP Low Qva OW-1 108 Sonic Core 7 74 19 0.33 0.021 Yes 1.3 4.4E-04 8.7E-04 SM Medium Qva OW-1 125 Sonic Core 2 90 8.1 0.30 0.088 22 7.7E-03 1.5E-02 SP-SM Low Qva OW-1 135 Sonic Core 4 70 26 0.28 0.0080 Yes 0.18 6.4E-05 1.3E-04 SM Medium Qva OW-1 153 Sonic Core 5 88 8.0 0.33 0.092 24 8.5E-03 1.7E-02 SP-SM Low Qva OW-1 182 Sonic Core 7 88 5.1 0.32 0.15 Yes 64 2.3E-02 4.4E-02 SP-SM Below water table Qva OW-2 56 Sonic Core 19 74 7.3 0.58 0.15 64 2.3E-02 4.4E-02 SP-SM Low Qva OW-2 72 Sonic Core 2 89 9.0 0.30 0.083 20 6.9E-03 1.4E-02 SP-SM Low Qva OW-2 82 Sonic Core 5 78 17 0.30 0.029 Yes 2.4 8.4E-04 1.7E-03 SM Medium Qva OW-2 91.5 Sonic Core 12 68 20 0.31 0.014 Yes 0.6 2.0E-04 3.9E-04 SM Medium Qva OW-2 107 Sonic Core 26 62 12 1.2 0.047 Yes 6.3 2.2E-03 4.3E-03 SW-SM Medium Qva OW-2 128 Sonic Core 14 70 16 0.42 0.024 Yes 1.6 5.8E-04 1.1E-03 SM Medium Qva OW-2 137.5 Sonic Core 5 88 7.4 0.36 0.13 48 1.7E-02 3.3E-02 SP-SM Low Qva OW-2 151.5 Sonic Core 10 56 34 0.27 0.0040 Yes 0.045 1.6E-05 3.1E-05 SM Medium Qva/Qvd OW-2 154 Sonic Core 37 58 5.2 2.2 0.25 177 6.3E-02 1.2E-01 SP-SM Low Qva OW-2 182.5 Sonic Core 10 87 2.8 0.41 0.18 92 3.2E-02 6.4E-02 SP Below water table Qva 13 4.6E-03 9.0E-03 Notes: 1 Treatment capacity classification from Table 5.2: Vadose Zone Treatment Capacity, in Guidance for UIC Wells that Manage Stormwater (Washington State Department of Ecology, 2006). Hazen, A., 1893, Some physical properties of sands and gravels: Massachusetts State Board of Health, 24th Annual Report. % = percent ASTM = ASTM International cm/sec = centimeters per second min = minute mm = millimeters UIC = underground injection control USCS = Unified Soil Classification System Geomean of Qva Samples Boring Number Depth (feet)Drilling Method Sieve Results (percent finer, mm)USCS Group Symbol Vadose Zone Treatment Capacity1 Approximate Hydraulic Conductivity, K (Hazen, 1893)Sieve Results (ASTM Percent Passing)Was 10% Size Estimated? Interpreted Geologic Unit Tested 10 14 OW-1 Slug Analysis-OW-1 Slug Test Plot-11/23/2016-pvh 0.01 0.1 1 10 0 2 4 6 8 10 12 14 16 18 Ch a n g e i n H e a d , Y t (F e e t ) Time (Seconds) Falling Head Test #1 Rising Head Test #1 Falling Head Test #2 Rising Head Test #2 Falling Head Test #3 Rising Head Test #3 LEGEND FI G . C -1 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington SLUG TESTS OBSERVATION WELL OW-1 November 2016 21-1-22082-003 FIG. C-1 SHANNON & WILSON, INC. Geotechnical and Environmental Consultants OW-1 Slug Analysis-OW-1 FH1-11/23/2016-pvh FI G . C -2 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington FALLING HEAD SLUG TEST 1 OBSERVATION WELL OW-1 November 2016 21-1-22082-003 FIG. C-2 SHANNON & WILSON, INC. Geotechnical and Environmental Consultants OW-1 Slug Analysis-OW-1 RH1-11/23/2016-pvh FI G . C -3 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington RISING HEAD SLUG TEST 1 OBSERVATION WELL OW-1 November 2016 21-1-22082-003 FIG. C-3 SHANNON & WILSON, INC. Geotechnical and Environmental Consultants OW-1 Slug Analysis-OW-1 FH2-11/23/2016-pvh FI G . C -4 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington FALLING HEAD SLUG TEST 2 OBSERVATION WELL OW-1 November 2016 21-1-22082-003 FIG. C-4 SHANNON & WILSON, INC. Geotechnical and Environmental Consultants OW-1 Slug Analysis-OW-1 RH2-11/23/2016-pvh FI G . C -5 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington RISING HEAD SLUG TEST 2 OBSERVATION WELL OW-1 November 2016 21-1-22082-003 FIG. C-5 SHANNON & WILSON, INC. Geotechnical and Environmental Consultants OW-1 Slug Analysis-OW-1 FH3-11/23/2016-pvh FI G . C -6 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington FALLING HEAD SLUG TEST 3 OBSERVATION WELL OW-1 November 2016 21-1-22082-003 FIG. C-6 SHANNON & WILSON, INC. Geotechnical and Environmental Consultants OW-1 Slug Analysis-OW-1 RH3-11/23/2016-pvh FI G . C -7 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington RISING HEAD SLUG TEST 3 OBSERVATION WELL OW-1 November 2016 21-1-22082-003 FIG. C-7 SHANNON & WILSON, INC. Geotechnical and Environmental Consultants OW-1 Water Levels-Figure C-8 - OW-1 Precip-11/23/2016-pvh 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0167.0 167.2 167.4 167.6 167.8 168.0 168.2 168.4 168.6 168.8 169.0 4/11/16 4/25/16 5/9/16 5/23/16 6/6/16 6/20/16 7/4/16 7/18/16 8/1/16 8/15/16 8/29/16 9/12/16 9/26/16 10/10/16 10/24/16 11/7/16 Ho u r l y P r e c i p i t a t i o n ( I n c h e s ) Gr o u n d w a t e r D e p t h B e l o w G r o u n d S u r f a c e ( F e e t ) Date (Local Time) OW-1 Transducer Data OW-1 Manual Data IW-1 Testing IW-2 Testing Brugger's Bog Daily Precipitation FI G . C -8 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington OBSERVATION WELL OW-1 GROUNDWATER DEPTH WITH PRECIPITATION DATA November 2016 21-1-22082-003 FIG. C-8SHANNON& WILSON, INC. Geotechnical and Environmental Consultants NOTES 1. The screen in observation well OW-1 is approximately 175.4 to 185.0 feet below ground surface, (approximately elevation 269.8 to 260.1 feet NAVD88). 2. Brugger's Bog precipitation data are from http://green.kingcounty.gov/wlr/waterres/hydrology/DataDownload.aspx 3. Black and white reproduction of this color original may lead to incorrect interpretation. OW-1 Water Levels-Figure C-9 - OW-1 BP-11/23/2016-pvh 32.2 32.4 32.6 32.8 33 33.2 33.4 33.6 33.8 34166.5 167.0 167.5 168.0 168.5 169.0 4/11/16 5/2/16 5/23/16 6/13/16 7/4/16 7/25/16 8/15/16 9/5/16 9/26/16 10/17/16 11/7/16 Ba r o m e t r i c P r e s s u r e ( F e e t o f W a t e r ) Gr o u n d w a t e r D e p t h B e l o w G r o u n d S u r f a c e ( F e e t ) Date (Local Time) OW-1 Transducer Data OW-1 Manual Data IW-1 Testing IW-2 Testing Barometric Pressure FI G . C -9 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington OBSERVATION WELL OW-1 GROUNDWATER DEPTH WITH BAROMETRIC PRESSURE DATA November 2016 21-1-22082-003 FIG. C-9SHANNON& WILSON, INC. Geotechnical and Environmental Consultants NOTES 1. The screen in observation well OW-1 is approximately 175.4 to 185.0 feet below ground surface, (approximately elevation 269.8 to 260.1 feet NAVD88). 2. Black and white reproduction of this color original may lead to incorrect interpretation. OW-2 Water Levels-Figure C-10 - OW-2 Precip-11/23/2016-pvh 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2167.0 167.2 167.4 167.6 167.8 168.0 168.2 168.4 168.6 168.8 169.0 8/22/16 8/29/16 9/5/16 9/12/16 9/19/16 9/26/16 10/3/16 10/10/16 10/17/16 10/24/16 10/31/16 11/7/16 Ba r o m e t r i c P r e s s u r e ( F e e t o f W a t e r ) Gr o u n d w a t e r D e p t h B e l o w G r o u n d S u r f a c e ( F e e t ) Date (Local Time) OW-2 Well Transducer Data OW-2 Manual Data IW-2 Testing Period Brugger's Bog Daily Precipitation FI G . C -10 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington OBSERVATION WELL OW-2 GROUNDWATER DEPTH WITH PRECIPITATION DATA November 2016 21-1-22082-003 FIG. C-10SHANNON& WILSON, INC. Geotechnical and Environmental Consultants NOTES 1. The screen in observation well OW-2 is approximately 179.2 to 183.9 feet below ground surface, (approximately elevation 265.4 to 260.8 feet (NAVD88)). 2. Black and white reproduction of this color original may lead to incorrect interpretation. OW-2 Water Levels-Figure C-11 - OW-2 BP-11/23/2016-pvh 32.0 32.2 32.4 32.6 32.8 33.0 33.2 33.4 33.6 33.8 34.0167.0 167.2 167.4 167.6 167.8 168.0 168.2 168.4 168.6 168.8 169.0 8/22/16 8/29/16 9/5/16 9/12/16 9/19/16 9/26/16 10/3/16 10/10/16 10/17/16 10/24/16 10/31/16 11/7/16 Ba r o m e t r i c P r e s s u r e ( F e e t o f W a t e r ) Gr o u n d w a t e r D e p t h B e l o w G r o u n d S u r f a c e ( F e e t ) Date (Local Time) OW-2 Well Transducer Data OW-2 Manual Data IW-2 Testing Period Barometric Pressure FI G . C -11 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington OBSERVATION WELL OW-2 GROUNDWATER DEPTH WITH BAROMETRIC PRESSURE November 2016 21-1-22082-003 FIG. C-11SHANNON& WILSON, INC. Geotechnical and Environmental Consultants NOTES 1. The screen in observation well OW-2 is approximately 179.2 to 183.9 feet below ground surface, (approximately elevation 265.4 to 260.8 feet (NAVD88)). 2. Groundwater level data for the OW-2 well were filtered using OW-1 data to remove the effects of regional aquifer trends during and after the IW -2 test period. 3. Black and white reproduction of this color original may lead to incorrect interpretation. OW-1 Water Levels-Figure C-12 - OW-1 BE Plot-11/23/2016-pvh y = 0.9012x -0.025 R² = 0.9878 -0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 -0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 Ch a n g e i n G r o u n d w a t e r L e v e l ( F e e t ) Change in Barometric Pressure (Feet of water) FI G . C -12 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington BAROMETRIC EFFICIENCY ESTIMATE FOR OBSERVATION WELL OW-1 November 2016 21-1-22082-003 FIG. C-12SHANNON& WILSON, INC. Geotechnical and Environmental Consultants NOTES 1. The screen in observation well OW-1 is approximately 175.4 to 185.0 feet below ground surface, (approximately elevation 269.8 to 260.1 feet (NAVD88)). 2. Barometric efficiency estimate of approximately 90% based on data collected between 5/6/16 and 5/10/16. OW-2 Water Levels-Figure C-13 - OW-2 BE-11/23/2016-pvh y = 0.8588x + 0.1323 R² = 0.8886 -0.3 -0.2 -0.2 -0.1 -0.1 0.0 0.1 0.1 0.2 0.2 -0.4 -0.3 -0.2 -0.1 0.0 0.1 Ch a n g e i n G r o u n d w a t e r L e v e l ( F e e t ) Change in Barometric Pressure (Feet of water) FI G . C -13 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington BAROMETRIC EFFICIENCY ESTIMATE FOR OBSERVATION WELL OW-2 November 2016 21-1-22082-003 FIG. C-13SHANNON& WILSON, INC. Geotechnical and Environmental Consultants NOTES 1. The screen in observation well OW-2 is approximately 179.2 to 183.9 feet below ground surface, (approximately elevation 265.4 to 260.8 feet (NAVD88)). 2. Barometric efficiency estimate of approximately 86% based on data collected between 9/6/16 and 9/18/16. OW-1 Water Levels-Figure C-14 - OW-1 IW-1 Test-11/23/2016-pvh 32.9 33 33.1 33.2 33.3 33.4 33.5 33.6 33.7 33.8 33.9168.0 168.1 168.2 168.3 168.4 168.5 168.6 168.7 168.8 168.9 169.0 4/22/16 4/24/16 4/26/16 4/28/16 4/30/16 5/2/16 5/4/16 5/6/16 Ba r o m e t r i c P r e s s u r e ( F e e t o f W a t e r ) Gr o u n d w a t e r D e p t h B e l o w G r o u n d S u r f a c e ( F e e t ) Date (Local Time) OW-1 Transducer Data OW-1 Manual Data IW-1 Testing OW-1 Transducer Data Adjusted for Barometric Efficiency Barometric Pressure FI G . C -14 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington OBSERVATION WELL OW-1 RESPONSE TO IW-1 TEST November 2016 21-1-22082-003 FIG. C-14SHANNON& WILSON, INC. Geotechnical and Environmental Consultants NOTES 1. The screen in observation well OW-1 is approximately 175.4 to 185.0 feet below ground surface, (approximately elevation 269.8 to 260.1 feet NAVD88). 2. Pilot dry well IW -1 was completed on 4/21/16 to 91.2 feet deep (approximately elevation 353.7 feet NAVD88). IW -1 infiltration test was performed on 4/25/16 from 10:03-18:34. 3. Black and white reproduction of this color original may lead to incorrect interpretation. OW-2 Water Levels-Figure C-15 - OW-2 Test-11/23/2016-pvh 140.0 145.0 150.0 155.0 160.0 165.0 170.0 10/11/16 10/12/16 10/13/16 10/14/16 10/15/16 10/16/16 10/17/16 10/18/16 Gr o u n d w a t e r D e p t h B e l o w G r o u n d S u r f a c e ( F e e t ) Date (Local Time) IW-2 Testing Period OW-2 VWP2 Data OW-2 VWP2 Sensor Depth OW-2 Well Transducer Data, Unadjusted for Regional Aquifer Trends OW-2 Well Transducer Data, Adjusted for Regional Aquifer Trends FI G . C -15 Hydrogeologic Report New Madrona K-8 Project Edmonds,Washington OW-2 OBSERVATION WELL AND VWP2 RESPONSE TO IW-2 TEST November 2016 21-1-22082-003 FIG. C-15SHANNON& WILSON, INC. Geotechnical and Environmental Consultants NOTES 1. The screen in observation well OW-2 is approximately 179.2 to 183.9 feet below ground surface, (approximately elevation 265.4 to 260.8 feet (NAVD88)). 2. Dry well IW-2 was completed at 120.4 feet deep (approximately elevation 324.0 feet). The IW -2 Infiltration test was performed from 10/11/16 9:09 to 10/12/16 4:09. 3. Groundwater level data for the OW-2 well were filtered using OW-1 data to remove the effects of regional aquifer trends during and after the IW-2 test period. 4. The OW-2 VWP2 sensor is approximately 146.3 feet deep (approximately elevation 298.4 feet). 5. The OW-2 VWP1 sensor is approximately 66.3 feet deep (approximately elevation 378.4 feet). It has remained dry during the monitoring period to date (8/24-11/5/16). 6. Black and white reproduction of this color original may lead to incorrect interpretation. April 21, 2016 Shannon & Wilson Paul Van Horne Attention Paul Van Horne: RE:Madrona K-8 School Lab ID:1604140 400 N. 34th Street, Suite 100 Seattle, WA 98103 3600 Fremont Ave. N. Seattle, WA 98103 T: (206) 352-3790 F: (206) 352-7178 info@fremontanalytical.com Fremont Analytical, Inc. received 2 sample(s) on 4/14/2016 for the analyses presented in the following report. This report consists of the following: - Case Narrative - Analytical Results - Applicable Quality Control Summary Reports - Chain of Custody All analyses were performed consistent with the Quality Assurance program of Fremont Analytical, Inc. Please contact the laboratory if you should have any questions about the results. Thank you for using Fremont Analytical. Sincerely, Color by SM2120 Cyanide by SM 4500-CN C, E Diesel and Heavy Oil by NWTPH-Dx/Dx Ext. Gasoline by NWTPH-Gx Ion Chromatography by EPA Method 300.0 Mercury by EPA Method 245.1 Total Metals by EPA Method 200.8 Total Dissolved Solids (TDS) by SM 2540C Total Phosphorous by EPA Method 365.3 Volatile Organic Compounds by EPA Method 8260C www.fremontanalytical.com Revision v1 DoD/ELAP Certification #L2371, ISO/ICC 17025:2005 ORELAP Certification: WA 100009-007 (NELAP Recognized) Page 1 of 29 Mike Ridgeway President www.fremontanalytical.com Revision v1 DoD/ELAP Certification #L2371, ISO/ICC 17025:2005 ORELAP Certification: WA 100009-007 (NELAP Recognized) Page 2 of 29 05/05/2016Date: Project:Madrona K-8 School CLIENT:Shannon & Wilson Lab Order:1604140 Work Order Sample Summary Lab Sample ID Client Sample ID Date/Time ReceivedDate/Time Collected 1604140-001 OW-1-041416 04/14/2016 11:18 AM 04/14/2016 4:07 PM 1604140-002 Trip Blank 04/13/2016 12:48 PM 04/14/2016 4:07 PM Note: If no "Time Collected" is supplied, a default of 12:00AM is assignedRevision v1 Page 3 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson 4/21/2016 Case Narrative 1604140 Date: WO#: I. SAMPLE RECEIPT: Samples receipt information is recorded on the attached Sample Receipt Checklist. II. GENERAL REPORTING COMMENTS: Results are reported on a wet weight basis unless dry-weight correction is denoted in the units field on the analytical report ("mg/kg-dry" or "ug/kg-dry"). Matrix Spike (MS) and MS Duplicate (MSD) samples are tested from an analytical batch of "like" matrix to check for possible matrix effect. The MS and MSD will provide site specific matrix data only for those samples which are spiked by the laboratory. The sample chosen for spike purposes may or may not have been a sample submitted in this sample delivery group. The validity of the analytical procedures for which data is reported in this analytical report is determined by the Laboratory Control Sample (LCS) and the Method Blank (MB). The LCS and the MB are processed with the samples and the MS/MSD to ensure method criteria are achieved throughout the entire analytical process. III. ANALYSES AND EXCEPTIONS: Exceptions associated with this report will be footnoted in the analytical results page(s) or the quality control summary page(s) and/or noted below. 1604140-001E C-COLOR has been Sub Contracted. Revision v1 Page 4 of 29 4/21/2016 Qualifiers & Acronyms 1604140 Date Reported: WO#: Qualifiers: * - Flagged value is not within established control limits B - Analyte detected in the associated Method Blank D - Dilution was required E - Value above quantitation range H - Holding times for preparation or analysis exceeded I - Analyte with an internal standard that does not meet established acceptance criteria J - Analyte detected below Reporting Limit N - Tentatively Identified Compound (TIC) Q - Analyte with an initial or continuing calibration that does not meet established acceptance criteria (<20%RSD, <20% Drift or minimum RRF) S - Spike recovery outside accepted recovery limits ND - Not detected at the Reporting Limit R - High relative percent difference observed Acronyms: %Rec - Percent Recovery CCB - Continued Calibration Blank CCV - Continued Calibration Verification DF - Dilution Factor HEM - Hexane Extractable Material ICV - Initial Calibration Verification LCS/LCSD - Laboratory Control Sample / Laboratory Control Sample Duplicate MB or MBLANK - Method Blank MDL - Method Detection Limit MS/MSD - Matrix Spike / Matrix Spike Duplicate PDS - Post Digestion Spike Ref Val - Reference Value RL - Reporting Limit RPD - Relative Percent Difference SD - Serial Dilution SGT - Silica Gel Treatment SPK - Spike Surr - Surrogate Revision v1 www.fremontanalytical.com Page 5 of 29 Project:Madrona K-8 School Client Sample ID:OW-1-041416 Collection Date:4/14/2016 11:18:00 AM Matrix:Groundwater Client:Shannon & Wilson Lab ID:1604140-001 Analyses Result Qual Units Date AnalyzedDFRL Analytical Report 4/21/2016 1604140 Date Reported: WO#: Diesel and Heavy Oil by NWTPH-Dx/Dx Ext.Analyst:CMBatch ID: 13481 Diesel (Fuel Oil)4/19/2016 11:45:00 PM50.0 µg/L 1ND Heavy Oil 4/19/2016 11:45:00 PM100µg/L 1ND Surr: 2-Fluorobiphenyl 4/19/2016 11:45:00 PM50-150 %Rec 173.5 Surr: o-Terphenyl 4/19/2016 11:45:00 PM50-150 %Rec 177.5 Gasoline by NWTPH-Gx Analyst:NGBatch ID: R28812 Gasoline 4/15/2016 4:35:49 AM50.0 µg/L 1ND Surr: 4-Bromofluorobenzene 4/15/2016 4:35:49 AM65-135 %Rec 199.4 Surr: Toluene-d8 4/15/2016 4:35:49 AM65-135 %Rec 198.8 Volatile Organic Compounds by EPA Method 8260C Analyst:NGBatch ID: R28811 Benzene 4/15/2016 4:35:49 AM1.00 µg/L 1ND Toluene 4/15/2016 4:35:49 AM1.00 µg/L 1ND Ethylbenzene 4/15/2016 4:35:49 AM1.00 µg/L 1ND m,p-Xylene 4/15/2016 4:35:49 AM1.00 µg/L 1ND o-Xylene 4/15/2016 4:35:49 AM1.00 µg/L 1ND Surr: Dibromofluoromethane 4/15/2016 4:35:49 AM45.4-152 %Rec 1102 Surr: Toluene-d8 4/15/2016 4:35:49 AM40.1-139 %Rec 194.3 Surr: 1-Bromo-4-fluorobenzene 4/15/2016 4:35:49 AM64.2-128 %Rec 197.2 Ion Chromatography by EPA Method 300.0 Analyst:MWBatch ID: R28832 Fluoride 4/15/2016 12:09:00 PM0.100 mg/L 1ND Chloride 4/15/2016 12:09:00 PM0.100 mg/L 16.38 Nitrite 4/15/2016 12:09:00 PM0.100 mg/L 10.159 Nitrate 4/15/2016 12:09:00 PM0.100 mg/L 11.01 Nitrate+Nitrite 4/15/2016 12:09:00 PM0.100 mg/L 11.17 Ortho-Phosphate 4/15/2016 12:09:00 PM0.200 mg/L 1ND Sulfate 4/15/2016 12:09:00 PM0.300 mg/L 122.6 Mercury by EPA Method 245.1 Analyst:MWBatch ID: 13469 Mercury 4/18/2016 3:00:59 PM0.100 µg/L 1ND Total Metals by EPA Method 200.8 Analyst:TNBatch ID: 13468 Antimony 4/15/2016 2:29:17 PM0.200 µg/L 1ND Revision v1 Page 6 of 29 Project:Madrona K-8 School Client Sample ID:OW-1-041416 Collection Date:4/14/2016 11:18:00 AM Matrix:Groundwater Client:Shannon & Wilson Lab ID:1604140-001 Analyses Result Qual Units Date AnalyzedDFRL Analytical Report 4/21/2016 1604140 Date Reported: WO#: Total Metals by EPA Method 200.8 Analyst:TNBatch ID: 13468 Arsenic 4/15/2016 2:29:17 PM1.00 µg/L 1ND Barium 4/15/2016 2:29:17 PM0.500 µg/L 128.6 Beryllium 4/15/2016 2:29:17 PM0.200 µg/L 1ND Cadmium 4/15/2016 2:29:17 PM0.200 µg/L 1ND Chromium 4/15/2016 2:29:17 PM0.500 µg/L 11.67 Copper 4/15/2016 2:29:17 PM0.500 µg/L 1ND Iron 4/15/2016 2:29:17 PM100µg/L 1ND Lead 4/15/2016 2:29:17 PM1.00 µg/L 1ND Manganese 4/15/2016 2:29:17 PM2.00 µg/L 1344 Nickel 4/15/2016 2:29:17 PM0.500 µg/L 12.94 Selenium 4/15/2016 2:29:17 PM1.00 µg/L 1ND Silver 4/15/2016 2:29:17 PM0.200 µg/L 1ND Sodium 4/15/2016 2:29:17 PM100µg/L 112,900 Thallium 4/15/2016 2:29:17 PM0.200 µg/L 1ND Zinc 4/15/2016 2:29:17 PM1.50 µg/L 127.3 Cyanide by SM 4500-CN C, E Analyst:NGBatch ID: 13500 Cyanide, Total 4/21/2016 10:03:00 AM0.0500 mg/L 1ND Total Phosphorous by EPA Method 365.3 Analyst:KTBatch ID: 13510 Phosphorus, Total (As P)4/21/2016 2:25:00 PM0.200 mg/L 1ND Total Dissolved Solids (TDS) by SM 2540C Analyst:KTBatch ID: R28863 Total Dissolved Solids 4/19/2016 4:04:00 PM5.00 mg/L 1182 Revision v1 Page 7 of 29 Page 8 of 29 Page 9 of 29 Page 10 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Cyanide by SM 4500-CN C, E 4/21/2016Date: Sample ID:MB-13500 Batch ID:13500 Analysis Date:4/21/2016 Prep Date:4/20/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:MBLKW RunNo:28891 SeqNo:543216 MBLKSampType: Cyanide, Total 0.0500ND Sample ID:LCS-13500 Batch ID:13500 Analysis Date:4/21/2016 Prep Date:4/20/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:LCSW RunNo:28891 SeqNo:543205 LCSSampType: Cyanide, Total 0.2500 99.8 80 1200.0500 00.250 Sample ID:1604152-001ADUP Batch ID:13500 Analysis Date:4/21/2016 Prep Date:4/20/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:BATCH RunNo:28891 SeqNo:543209 DUPSampType: Cyanide, Total 200.0500 0ND Sample ID:1604152-001AMS Batch ID:13500 Analysis Date:4/21/2016 Prep Date:4/20/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:BATCH RunNo:28891 SeqNo:543210 MSSampType: Cyanide, Total 0.2500 100 80 1200.0500 0.023500.274 Sample ID:1604152-001AMSD Batch ID:13500 Analysis Date:4/21/2016 Prep Date:4/20/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:BATCH RunNo:28891 SeqNo:543211 MSDSampType: Cyanide, Total 0.2500 72.6 80 120 30 S0.0500 0.02350 0.2741 28.80.205 NOTES: S - Outlying spike recovery(ies) observed. A duplicate analysis was performed and recovered within range. Revision v1 Page 11 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Ion Chromatography by EPA Method 300.0 4/21/2016Date: Sample ID:MB-R28832 Batch ID:R28832 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:MBLKW RunNo:28832 SeqNo:541986 MBLKSampType: Fluoride 0.100ND Chloride 0.100ND Nitrite 0.100ND Nitrate 0.100ND Nitrate+Nitrite 0.100ND Sulfate 0.300ND Sample ID:LCS-R28832 Batch ID:R28832 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:LCSW RunNo:28832 SeqNo:541987 LCSSampType: Fluoride 2.000 105 90 1100.100 02.09 Chloride 3.000 96.0 90 1100.100 02.88 Nitrite 3.000 98.9 90 1100.100 02.97 Nitrate 3.000 101 90 1100.100 03.03 Nitrate+Nitrite 6.000 100 90 1100.100 06.00 Sulfate 15.00 104 90 1100.300 015.6 Sample ID:1604140-001DDUP Batch ID:R28832 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:OW-1-041416 RunNo:28832 SeqNo:541989 DUPSampType: Fluoride 200.100 0ND Chloride 200.100 6.376 0.1336.37 Nitrite 200.100 0.1594 0.8740.161 Nitrate 200.100 1.011 0.7091.02 Nitrate+Nitrite 200.100 1.171 0.7321.18 Sulfate 200.300 22.62 0.14222.6 Revision v1 Page 12 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Ion Chromatography by EPA Method 300.0 4/21/2016Date: Sample ID:1604140-001DMS Batch ID:R28832 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:OW-1-041416 RunNo:28832 SeqNo:541990 MSSampType: Fluoride 2.000 101 80 1200.100 0.066802.08 Chloride 3.000 86.7 80 1200.100 6.3768.98 Nitrite 3.000 96.5 80 1200.100 0.15943.05 Nitrate 3.000 98.1 80 1200.100 1.0113.95 Nitrate+Nitrite 6.000 97.3 80 1200.100 1.1717.01 Sulfate 15.00 97.3 80 1200.300 22.6237.2 Sample ID:1604140-001DMSD Batch ID:R28832 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:OW-1-041416 RunNo:28832 SeqNo:541991 MSDSampType: Fluoride 2.000 101 80 120 200.100 0.06680 2.084 0.1612.09 Chloride 3.000 86.3 80 120 200.100 6.376 8.978 0.1368.97 Nitrite 3.000 96.2 80 120 200.100 0.1594 3.053 0.2863.04 Nitrate 3.000 97.0 80 120 200.100 1.011 3.953 0.7923.92 Nitrate+Nitrite 6.000 96.6 80 120 200.100 1.171 7.006 0.5716.97 Sulfate 15.00 95.8 80 120 200.300 22.62 37.22 0.62337.0 Revision v1 Page 13 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Total Phosphorous by EPA Method 365.3 4/21/2016Date: Sample ID:MB-13510 Batch ID:13510 Analysis Date:4/21/2016 Prep Date:4/21/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:MBLKW RunNo:28899 SeqNo:543434 MBLKSampType: Phosphorus, Total (As P)0.200ND Sample ID:LCS-13510 Batch ID:13510 Analysis Date:4/21/2016 Prep Date:4/21/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:LCSW RunNo:28899 SeqNo:543435 LCSSampType: Phosphorus, Total (As P)2.000 109 65 1350.200 02.17 Sample ID:1604140-001HDUP Batch ID:13510 Analysis Date:4/21/2016 Prep Date:4/21/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:OW-1-041416 RunNo:28899 SeqNo:543437 DUPSampType: Phosphorus, Total (As P)300.200 0ND Sample ID:1604140-001HMS Batch ID:13510 Analysis Date:4/21/2016 Prep Date:4/21/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:OW-1-041416 RunNo:28899 SeqNo:543438 MSSampType: Phosphorus, Total (As P)2.000 94.2 65 1350.200 0.018001.90 Sample ID:1604140-001HMSD Batch ID:13510 Analysis Date:4/21/2016 Prep Date:4/21/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:OW-1-041416 RunNo:28899 SeqNo:543439 MSDSampType: Phosphorus, Total (As P)2.000 108 65 135 300.200 0.01800 1.902 13.52.18 Revision v1 Page 14 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Total Dissolved Solids (TDS) by SM 2540C 4/21/2016Date: Sample ID:MB-R28863 Batch ID:R28863 Analysis Date:4/19/2016 Prep Date:4/19/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:MBLKW RunNo:28863 SeqNo:542617 MBLKSampType: Total Dissolved Solids 5.00ND Sample ID:LCS-R28863 Batch ID:R28863 Analysis Date:4/19/2016 Prep Date:4/19/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:LCSW RunNo:28863 SeqNo:542618 LCSSampType: Total Dissolved Solids 300.0 101 65 13510.0 0304 Sample ID:1604140-001DDUP Batch ID:R28863 Analysis Date:4/19/2016 Prep Date:4/19/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:mg/L RL Client ID:OW-1-041416 RunNo:28863 SeqNo:542620 DUPSampType: Total Dissolved Solids 305.00 182.0 10.9203 Revision v1 Page 15 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Total Metals by EPA Method 200.8 4/21/2016Date: Sample ID:MB-13468 Batch ID:13468 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:MBLKW RunNo:28822 SeqNo:541791 MBLKSampType: Antimony 0.200ND Arsenic 1.00ND Barium 0.500ND Beryllium 0.200ND Cadmium 0.200ND Chromium 0.500ND Copper 0.500ND Iron 100ND Lead 1.00ND Manganese 2.00ND Nickel 0.500ND Selenium 1.00ND Silver 0.200ND Sodium 100ND Thallium 0.200ND Zinc 1.50ND Sample ID:LCS-13468 Batch ID:13468 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:LCSW RunNo:28822 SeqNo:541792 LCSSampType: Antimony 5.000 90.4 85 1150.200 04.52 Arsenic 100.0 101 85 1151.00 0101 Barium 100.0 99.3 85 1150.500 099.3 Beryllium 5.000 103 85 1150.200 05.16 Cadmium 5.000 114 85 1150.200 05.70 Chromium 100.0 92.5 85 1150.500 092.5 Copper 100.0 96.2 85 1150.500 096.2 Iron 1,000 109 50 15010001,090 Lead 50.00 90.7 85 1151.00 045.3 Revision v1 Page 16 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Total Metals by EPA Method 200.8 4/21/2016Date: Sample ID:LCS-13468 Batch ID:13468 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:LCSW RunNo:28822 SeqNo:541792 LCSSampType: Manganese 100.0 100 85 1152.00 0100 Nickel 100.0 95.5 85 1150.500 095.5 Selenium 10.00 99.4 85 1151.00 09.94 Silver 5.000 93.2 85 1150.200 04.66 Sodium 1,000 99.1 50 1501000991 Thallium 2.500 90.7 85 1150.200 02.27 Zinc 100.0 100 85 1151.50 0100 Sample ID:1604116-001CDUP Batch ID:13468 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28822 SeqNo:541794 DUPSampType: Antimony 30 R0.200 0.4710 80.10.202 Arsenic 301.00 0ND Barium 300.500 37.74 0.95538.1 Beryllium 300.200 0ND Cadmium 300.200 0ND Chromium 300.500 0.5610 25.10.722 Copper 300.500 0.5540 10.9ND Iron 301000ND Lead 301.00 0ND Manganese 302.00 5.155 0.3205.17 Nickel 300.500 0.7520 22.10.939 Selenium 301.00 0ND Silver 300.200 0ND Sodium 3010057,370 5.4454,300 Thallium 300.200 0ND Zinc 301.50 2.528 15.52.95 NOTES: R - High RPD observed. The method is in control as indicated by the LCS. Revision v1 Page 17 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Total Metals by EPA Method 200.8 4/21/2016Date: Sample ID:1604116-001CMS Batch ID:13468 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28822 SeqNo:541795 MSSampType: Antimony 25.00 89.3 70 1300.200 0.471022.8 Arsenic 500.0 106 70 1301.00 0.8205532 Barium 500.0 98.5 70 1300.500 37.74530 Beryllium 25.00 99.7 70 1300.200 024.9 Cadmium 25.00 112 70 1300.200 0.0160028.0 Chromium 500.0 103 70 1300.500 0.5610517 Copper 500.0 97.8 70 1300.500 0.5540489 Iron 5,000 104 50 15010045.565,250 Lead 250.0 87.9 70 1301.00 0.07550220 Manganese 500.0 100 70 1302.00 5.155508 Nickel 500.0 98.3 70 1300.500 0.7520492 Selenium 50.00 103 70 1301.00 051.5 Silver 25.00 67.8 70 130 S0.200 017.0 Sodium 5,000 62.9 50 15010057,37060,500 Thallium 12.50 89.4 70 1300.200 0.00650011.2 Zinc 500.0 101 70 1301.50 2.528508 NOTES: S - Outlying spike recovery(ies) observed. A duplicate analysis was performed and recovered within range. Sample ID:1604116-001CMSD Batch ID:13468 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28822 SeqNo:541796 MSDSampType: Antimony 25.00 89.1 70 130 300.200 0.4710 22.79 0.17122.7 Arsenic 500.0 105 70 130 301.00 0.8205 531.7 1.30525 Barium 500.0 96.9 70 130 300.500 37.74 530.4 1.55522 Beryllium 25.00 96.0 70 130 300.200 0 24.92 3.7924.0 Cadmium 25.00 111 70 130 300.200 0.01600 28.03 0.56027.9 Chromium 500.0 99.4 70 130 300.500 0.5610 516.6 3.79497 Copper 500.0 96.3 70 130 300.500 0.5540 489.4 1.55482 Iron 5,000 105 50 150 3010045.56 5,246 1.135,310 Revision v1 Page 18 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Total Metals by EPA Method 200.8 4/21/2016Date: Sample ID:1604116-001CMSD Batch ID:13468 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28822 SeqNo:541796 MSDSampType: Lead 250.0 86.4 70 130 301.00 0.07550 219.8 1.76216 Manganese 500.0 100 70 130 302.00 5.155 507.5 0.177507 Nickel 500.0 98.4 70 130 300.500 0.7520 492.2 0.156493 Selenium 50.00 98.3 70 130 301.00 0 51.48 4.6249.2 Silver 25.00 75.0 70 130 300.200 0 16.96 10.018.7 Sodium 5,000 54.7 50 150 3010057,370 60,510 0.67960,100 Thallium 12.50 88.5 70 130 300.200 0.006500 11.18 1.0311.1 Zinc 500.0 101 70 130 301.50 2.528 508.0 0.150507 Revision v1 Page 19 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Mercury by EPA Method 245.1 4/21/2016Date: Sample ID:MB-13469 Batch ID:13469 Analysis Date:4/18/2016 Prep Date:4/18/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:MBLKW RunNo:28842 SeqNo:542145 MBLKSampType: Mercury 0.100ND Sample ID:LCS-13469 Batch ID:13469 Analysis Date:4/18/2016 Prep Date:4/18/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:LCSW RunNo:28842 SeqNo:542146 LCSSampType: Mercury 2.500 90.8 85 1150.100 02.27 Sample ID:1604092-001ADUP Batch ID:13469 Analysis Date:4/18/2016 Prep Date:4/18/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28842 SeqNo:542148 DUPSampType: Mercury 200.100 0ND Sample ID:1604092-001AMS Batch ID:13469 Analysis Date:4/18/2016 Prep Date:4/18/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28842 SeqNo:542149 MSSampType: Mercury 2.500 96.4 80 1200.100 02.41 Sample ID:1604092-001AMSD Batch ID:13469 Analysis Date:4/18/2016 Prep Date:4/18/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28842 SeqNo:542150 MSDSampType: Mercury 2.500 96.0 80 120 200.100 0 2.410 0.4162.40 Revision v1 Page 20 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Diesel and Heavy Oil by NWTPH-Dx/Dx Ext. 4/21/2016Date: Sample ID:MB-13481 Batch ID:13481 Analysis Date:4/19/2016 Prep Date:4/18/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:MBLKW RunNo:28866 SeqNo:542740 MBLKSampType: Diesel (Fuel Oil)50.0ND Heavy Oil 100ND Surr: 2-Fluorobiphenyl 80.00 63.3 50 15050.6 Surr: o-Terphenyl 80.00 67.3 50 15053.8 Sample ID:LCS-13481 Batch ID:13481 Analysis Date:4/19/2016 Prep Date:4/18/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:LCSW RunNo:28866 SeqNo:542739 LCSSampType: Diesel (Fuel Oil)1,000 67.6 65 13550.0 0676 Surr: 2-Fluorobiphenyl 80.00 73.5 50 15058.8 Surr: o-Terphenyl 80.00 75.6 50 15060.5 Sample ID:1604132-002BDUP Batch ID:13481 Analysis Date:4/19/2016 Prep Date:4/18/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28866 SeqNo:542716 DUPSampType: Diesel (Fuel Oil)3051.8 0ND Diesel Range Organics (C12-C24)3051.8 459.7 19.5559 Heavy Oil 30 R104878.6 88.52,270 Surr: 2-Fluorobiphenyl 82.88 79.6 50 150 065.9 Surr: o-Terphenyl 82.88 71.6 50 150 059.4 NOTES: R - High RPD observed. The method is in control as indicated by the LCS. DRO - Indicates the presence of unresolved compounds eluting from dodecane through tetracosane (C12-C24). Revision v1 Page 21 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Diesel and Heavy Oil by NWTPH-Dx/Dx Ext. 4/21/2016Date: Sample ID:1604140-001BMS Batch ID:13481 Analysis Date:4/20/2016 Prep Date:4/18/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:OW-1-041416 RunNo:28866 SeqNo:542718 MSSampType: Diesel (Fuel Oil)998.9 63.2 65 135 S49.9 37.33668 Surr: 2-Fluorobiphenyl 79.91 73.8 50 15059.0 Surr: o-Terphenyl 79.91 73.7 50 15058.9 NOTES: S - Outlying spike recovery(ies) observed. A duplicate analysis was performed and recovered within range. Sample ID:1604140-001BMSD Batch ID:13481 Analysis Date:4/20/2016 Prep Date:4/18/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:OW-1-041416 RunNo:28866 SeqNo:542719 MSDSampType: Diesel (Fuel Oil)996.3 67.9 65 135 3049.8 37.33 668.4 6.56714 Surr: 2-Fluorobiphenyl 79.71 75.1 50 150 0059.8 Surr: o-Terphenyl 79.71 77.2 50 150 0061.5 Sample ID:1604155-005EDUP Batch ID:13481 Analysis Date:4/20/2016 Prep Date:4/18/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28866 SeqNo:542729 DUPSampType: Diesel (Fuel Oil)3050.0 0ND Heavy Oil 301000ND Surr: 2-Fluorobiphenyl 79.97 69.0 50 150 055.2 Surr: o-Terphenyl 79.97 70.9 50 150 056.7 Revision v1 Page 22 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Gasoline by NWTPH-Gx 4/21/2016Date: Sample ID:LCS-R28812 Batch ID:R28812 Analysis Date:4/14/2016 Prep Date:4/14/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:LCSW RunNo:28812 SeqNo:541564 LCSSampType: Gasoline 500.0 100 65 13550.0 0502 Surr: Toluene-d8 25.00 97.8 65 13524.4 Surr: 4-Bromofluorobenzene 25.00 99.9 65 13525.0 Sample ID:MB-R28812 Batch ID:R28812 Analysis Date:4/14/2016 Prep Date:4/14/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:MBLKW RunNo:28812 SeqNo:541565 MBLKSampType: Gasoline 50.0ND Surr: Toluene-d8 25.00 99.8 65 13524.9 Surr: 4-Bromofluorobenzene 25.00 99.7 65 13524.9 Sample ID:1602099-051AMS Batch ID:R28812 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28812 SeqNo:541555 MSSampType: Gasoline 500.0 108 65 135 H50.0 0540 Surr: Toluene-d8 25.00 101 65 135 H25.2 Surr: 4-Bromofluorobenzene 25.00 101 65 135 H25.4 Sample ID:1602099-051AMSD Batch ID:R28812 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28812 SeqNo:541556 MSDSampType: Gasoline 500.0 111 65 135 30 H50.0 0 540.1 3.07557 Surr: Toluene-d8 25.00 98.2 65 135 0 H024.6 Surr: 4-Bromofluorobenzene 25.00 98.6 65 135 0 H024.6 Revision v1 Page 23 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Gasoline by NWTPH-Gx 4/21/2016Date: Sample ID:1604115-005ADUP Batch ID:R28812 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28812 SeqNo:541558 DUPSampType: Gasoline 3050.0 0ND Surr: Toluene-d8 25.00 99.8 65 135 0025.0 Surr: 4-Bromofluorobenzene 25.00 101 65 135 0025.4 Revision v1 Page 24 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Volatile Organic Compounds by EPA Method 8260C 4/21/2016Date: Sample ID:LCS-R28811 Batch ID:R28811 Analysis Date:4/14/2016 Prep Date:4/14/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:LCSW RunNo:28811 SeqNo:541551 LCSSampType: Benzene 20.00 86.1 69.3 1321.00 017.2 Toluene 20.00 96.4 61.3 1451.00 019.3 Ethylbenzene 20.00 91.1 72 1301.00 018.2 m,p-Xylene 40.00 92.6 70.3 1341.00 037.0 o-Xylene 20.00 93.0 72.1 1311.00 018.6 Surr: Dibromofluoromethane 25.00 92.2 45.4 15223.1 Surr: Toluene-d8 25.00 110 40.1 13927.4 Surr: 1-Bromo-4-fluorobenzene 25.00 102 64.2 12825.6 Sample ID:MB-R28811 Batch ID:R28811 Analysis Date:4/14/2016 Prep Date:4/14/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:MBLKW RunNo:28811 SeqNo:541552 MBLKSampType: Benzene 1.00ND Toluene 1.00ND Ethylbenzene 1.00ND m,p-Xylene 1.00ND o-Xylene 1.00ND Surr: Dibromofluoromethane 25.00 104 45.4 15226.0 Surr: Toluene-d8 25.00 94.9 40.1 13923.7 Surr: 1-Bromo-4-fluorobenzene 25.00 98.3 64.2 12824.6 Sample ID:1602099-051AMS Batch ID:R28811 Analysis Date:4/14/2016 Prep Date:4/14/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28811 SeqNo:541536 MSSampType: Benzene 20.00 101 65.4 138 H1.00 020.1 Toluene 20.00 91.8 64 139 H1.00 018.4 Ethylbenzene 20.00 97.4 64.5 136 H1.00 019.5 m,p-Xylene 40.00 99.8 63.3 135 H1.00 039.9 Revision v1 Page 25 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Volatile Organic Compounds by EPA Method 8260C 4/21/2016Date: Sample ID:1602099-051AMS Batch ID:R28811 Analysis Date:4/14/2016 Prep Date:4/14/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28811 SeqNo:541536 MSSampType: o-Xylene 20.00 100 65.4 134 H1.00 020.0 Surr: Dibromofluoromethane 25.00 105 45.4 152 H26.3 Surr: Toluene-d8 25.00 96.4 40.1 139 H24.1 Surr: 1-Bromo-4-fluorobenzene 25.00 99.8 64.2 128 H24.9 Sample ID:1602099-051AMSD Batch ID:R28811 Analysis Date:4/14/2016 Prep Date:4/14/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28811 SeqNo:541537 MSDSampType: Benzene 20.00 101 65.4 138 30 H1.00 0 20.12 0.69320.3 Toluene 20.00 92.0 64 139 30 H1.00 0 18.36 0.21818.4 Ethylbenzene 20.00 104 64.5 136 30 H1.00 0 19.48 6.4120.8 m,p-Xylene 40.00 104 63.3 135 30 H1.00 0 39.90 3.8841.5 o-Xylene 20.00 104 65.4 134 30 H1.00 0 20.02 3.9220.8 Surr: Dibromofluoromethane 25.00 104 45.4 152 0 H025.9 Surr: Toluene-d8 25.00 95.1 40.1 139 0 H023.8 Surr: 1-Bromo-4-fluorobenzene 25.00 102 64.2 128 0 H025.5 Sample ID:1604115-005ADUP Batch ID:R28811 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28811 SeqNo:541544 DUPSampType: Benzene 301.00 0ND Toluene 301.00 0ND Ethylbenzene 301.00 0ND m,p-Xylene 301.00 0ND o-Xylene 301.00 0ND Surr: Dibromofluoromethane 25.00 102 45.4 152 025.5 Surr: Toluene-d8 25.00 92.4 40.1 139 023.1 Surr: 1-Bromo-4-fluorobenzene 25.00 99.4 64.2 128 024.9 Revision v1 Page 26 of 29 Project:Madrona K-8 School CLIENT:Shannon & Wilson Work Order:1604140 QC SUMMARY REPORT Volatile Organic Compounds by EPA Method 8260C 4/21/2016Date: Sample ID:1604115-005ADUP Batch ID:R28811 Analysis Date:4/15/2016 Prep Date:4/15/2016 Analyte Result SPK value SPK Ref Val %REC RPD Ref Val %RPDLowLimitHighLimit RPDLimit Qual Units:µg/L RL Client ID:BATCH RunNo:28811 SeqNo:541544 DUPSampType: Revision v1 Page 27 of 29 Date Received:4/14/2016 4:07:00 PM Client Name:SW Work Order Number:1604140 Sample Log-In Check List Erica SilvaLogged by: Item Information How was the sample delivered?Client Is Chain of Custody complete?Yes No Not Present Was an attempt made to cool the samples?Yes No NA Are samples properly preserved?Yes No Was preservative added to bottles?Yes No NA Did all samples containers arrive in good condition(unbroken)?Yes No Does paperwork match bottle labels?Yes No Are matrices correctly identified on Chain of Custody?Yes No Is it clear what analyses were requested?Yes No Is there headspace in the VOA vials?Yes No NA 1. 2. 6. 10. 11. 12. 13. 14. 15. 16. 17.Were all holding times able to be met?Yes No Chain of Custody Log In 7.Were all items received at a temperature of >0°C to 10.0°C Yes No NA 8.Sample(s) in proper container(s)?Yes No 9.Sufficient sample volume for indicated test(s)?Yes No H2SO4 to 001H Special Handling (if applicable) 18. 19. Was client notified of all discrepancies with this order?Yes No NA Person Notified:Date: Regarding: Via:eMail Phone Fax In Person Additional remarks: Client Instructions: By Whom: Coolers are present?Yes No NA3. Shipping container/cooler in good condition?Yes No4. Custody Seals present on shipping container/cooler? (Refer to comments for Custody Seals not intact) Yes No Not Required5. * Item #Temp ºC Cooler 5.0 Sample 4.2 Temp Blank 2.4 Page 1 of 1Note: DoD/ELAP and TNI require items to be received at 4°C +/- 2°C* Revision v1 Page 28 of 29 Page 29 of 29 21-1-22082-003 APPENDIX D GROUNDWATER MODELING 21-1-22082-003-R1f-AD/wp/lk 21-1-22082-003 D-i APPENDIX D GROUNDWATER MODELING TABLE OF CONTENTS Page D.1 INTRODUCTION .......................................................................................................... D-1 D.2 MODELING APPROACH ............................................................................................. D-1 D.3 MODEL STRUCTURE AND LAYERING ................................................................... D-2 D.4 HYDRAULIC PARAMETERS ..................................................................................... D-2 D.5 BOUNDARY CONDITIONS AND INITIAL GROUNDWATER LEVELS ............... D-2 D.6 UNDERGROUND INJECTION CONTROL WELL RECHARGE SIMULATIONS.. D-3 D.7 SUMMARY .................................................................................................................... D-4 D.8 REFERENCES ............................................................................................................... D-4 TABLE D-1 Modeled Hydrostratigraphic Layers and Hydraulic Properties .......................... D-2 FIGURES D-1 Model Domain and Boundaries D-2 Planned UIC Wells D-3 Model Mesh in Northern UIC Wellfield Area D-4 Model Sections North-South and West-East Through Well IW-2 D-5 Model Input Hydrograph & Predicted Groundwater Levels at UIC Areas – Base Case D-6 Predicted Groundwater Levels Along Transect Through UIC Area 2 – Base Case D-7 Model Input Hydrograph & Predicted Groundwater Levels at UIC Area 2 – Sensitivity Cases D-8 Predicted Groundwater Levels Along Transect Through UIC Area 2 – Sensitivity Case 3 21-1-22082-003-R1f-AD/wp/lk 21-1-22082-003 D-1 APPENDIX D GROUNDWATER MODELING D.1 INTRODUCTION We developed a three-dimensional groundwater model (model) based on the site explorations and our conceptual hydrogeologic model. The objective of the model was to predict the likely groundwater response to the planned underground injection control (UIC) wellfield operation. In particular, the model was used to evaluate water mounding above potential perching layers and the potential for seepage to occur at the slopes to the west and east of the school property. This appendix provides a description of the model setup and a summary of the modeling results. The proposed UIC wellfield consisting of 16 wells in 4 clusters of either 3 or 5 wells each. The UIC well spacing within the clusters ranged from 30 to 50 feet, based on the proposed layout provided by KPFF Consulting Engineers. We simulated the recharge occurring into the unsaturated zone of the Vashon advance outwash (Qva) unit that overlies a 5-foot-thick perching layer and a deeper, saturated Qva aquifer. D.2 MODELING APPROACH The model was constructed using numerical modeling techniques to simulate unsaturated zone and groundwater flow conditions for the project area. The model approach included:  Selecting an appropriate numerical model and the supporting software.  Constructing a three-dimensional representation of the model area that includes the hydrogeologic framework, hydraulic properties, and boundary conditions.  Performing simulations for one base and three sensitivity case scenarios.  Evaluating model results. We used the U.S. Geological Survey’s numerical groundwater flow code MODFLOW-2005 (Harbaugh, 2005) to simulate the groundwater flow system in the project area. We used the graphical interface program Groundwater Vistas version 6 (Environmental Simulations Incorporated, 2016) as a pre- and post-processor to create and manage model input and output files for MODFLOW-2005. 21-1-22082-003-R1f-AD/wp/lk 21-1-22082-003 D-2 D.3 MODEL STRUCTURE AND LAYERING Figure D-1 shows the model domain which has dimensions 2,400 feet by 2,000 feet. The model grid consists of computational cells with dimensions ranging from 30 feet by 30 feet to 2.5 feet by 2.5 feet in plan view, with the smallest cells assigned at and near the planned UIC wells (Figure D-2). The model’s upper surface (top of layer 1) was established by interpolating a digital elevation map dataset for the area to the model grid (Figure D-3). Vertically, the model thickness ranges from about 230 feet thick beneath the school property to 125 feet in the valley area west of the school (Figure D-4). The model base is at Elevation 225 feet. The vertical thickness of the model is divided into three layers based on the conceptual hydrogeologic profiles. D.4 HYDRAULIC PARAMETERS The main hydraulic parameters in the model are hydraulic conductivity (horizontal and vertical) and storage coefficients (unconfined and confined). We assigned the model hydraulic conductivity values based on empirical correlations with grain size test results from samples collected during Shannon & Wilson, Inc.’s subsurface explorations at the site, slug test results, and the two pilot-scale recharge tests. As no formal testing was performed to estimate the storage coefficients, we used professional judgment to assign parameter values. Table D-1 presents the modeled parameters for each layer. TABLE D-1 MODELED HYDROSTRATIGRAPHIC LAYERS AND HYDRAULIC PROPERTIES Model Layer Horizontal Hydraulic Conductivity (feet per day) Vertical Hydraulic Conductivity (feet per day) Specific Yield, Storativity Layer Elevation Range (feet) Model Layer Thickness (feet) Unit Description 1 30 3 0.1, 1 x 10-5 Greater than 350 to 298. 52 to 162 Unsaturated Qva outwash. 2 0.1 0.01 298 to 293 5 Low permeability perching layer within Qva. 3 30 3 293 to 225 68 Qva outwash aquifer. D.5 BOUNDARY CONDITIONS AND INITIAL GROUNDWATER LEVELS The model uses MODFLOW Constant Head boundary conditions along the northern and southern limits of the domain to simulate groundwater inflow and outflow, and to establish initial 21-1-22082-003-R1f-AD/wp/lk 21-1-22082-003 D-3 (existing) groundwater conditions. For the purpose of this evaluation, these heads were Elevations 299 and 300 feet, respectively. Therefore, the existing groundwater levels are slightly above the base of layer 1. D.6 UNDERGROUND INJECTION CONTROL WELL RECHARGE SIMULATIONS For the Base Case model run, we simulated a total stormwater recharge hydrograph that we were provided by the design engineers KPFF Consulting Engineers. This hydrograph represents a 100-year, 24-hour storm event. We distributed this flux between the 16 wells that are part of the four clusters of UIC wells (Areas 1, 2, 3, and 4; Figure D-2). The recharge flux was assigned to model layer 1. We used 24 hourly model stress periods to simulate the storm event. The peak hourly recharge rate per well ranged from 102 to 130 gallons per minute. Figure D-5 shows the model-predicted water level response to the 24-hour storm event at the centers of the four UIC Areas and the total input hourly hydrograph. These modeled responses represent the anticipated temporary perching of infiltrating water above the lower permeability silty sand layer that is situated above the regional aquifer. The results indicate that the storm event would temporarily raise water levels to a peak of Elevation 310 feet at the center of UIC Area 2 (which has five UIC wells), and to below Elevation 306 feet at the center of the three other UIC areas. Figure D-6 shows the predicted hydrograph for four points along a 400-foot-long east-west transect extending from the center of UIC Area 2 (OW-2) to the bottom of the ravine located west of the UIC arrays (which is at about Elevation 370 feet). The results indicate that the mounding effect of the storm would diminish to the west of OW-2, and the temporarily perched water table would come within 70 feet of the slope surface. To evaluate the effect that uncertainty of key model parameters on the Base Case results, we performed three sensitivity cases. These involved the re-simulating the 24-hour storm with the following changes to the Base Case model:  Sensitivity Case 1 – lower the Qva aquifer Kh and Kv to 3 and 0.3 feet per day, respectively;  Sensitivity Case 2 – increase the elevation of the 5-foot-thick perching layer by 15 feet; and  Sensitivity Case 3 – combination of Cases 1 and 2. Figure D-7 shows the predicted results for the three sensitivity cases and the Base Case at the center of UIC Area 2 (OW-2), and Figure D-8 shows the predicted hydrographs for four points along the east-west transect from OW-2. The results indicate that the induced perched water table would rise to a peak of Elevation 328 feet at the center of UIC Area 2 (for the most conservative Sensitivity Case 3), which is 117 feet below ground surface. As with the Base 21-1-22082-003-R1f-AD/wp/lk 21-1-22082-003 D-4 Case, the water would remain more than 50 feet below the toe of the slope to the west of UIC Area 2 for Sensitivity Case 3. D.7 SUMMARY For the Base Case scenario, the model predicts that the water table will rise by between 7 and 11 feet at the center of the four UIC areas during a 100-year, 24-hour storm event. The resulting mound would be 70 feet or more below the surface of the nearby ravine slope. We ran a limited sensitivity analysis of the Base Case involving reducing the hydraulic conductivity of the Qva unit by a factor of 10 and increasing the elevation of the perching unit by 15 feet. The most conservative sensitivity case resulted in the peak rise in the water table at the UIC area of up to 14 feet, to a maximum elevation of 328 feet (which is 117 feet below ground surface). The resulting mound would be 50 feet or more below the surface of the nearby ravine slope for the most conservative sensitivity case. Our model provides a framework for estimating how much groundwater mounding may result during the given storm assuming the UIC wells are 100 percent efficient. The Base Case modeling predicted an operating water level of up to about 18 feet inside the UIC wells during the design storm event. However, depending on the well drilling method, development, and maintenance practices, the actual initial UIC well efficiencies will be less (e.g., 50 to 75 percent). Additionally, UIC well efficiency typically decreases with time of operation, depending on the degree of inflow water quality control and well maintenance frequency. Therefore, we would expect the operating water level in the UIC wells to increase in the future. For example, at 50 percent well efficiency, the operating water level inside the UIC wells might be closer to about 36 feet for the modeled storm. D.8 REFERENCES Environmental Simulations Incorporated (ESI), 2012, Groundwater Vistas, v. 6: Reinholds, Pa., Environmental Simulations Incorporated. Harbaugh, A. W., 2005, MODFLOW-2005: the U.S. Geological Survey modular ground-water model--the ground-water flow process3: U.S. Geological Survey Techniques of Water- Resources Investigations Book 6, Chapter A16, 1 v., available: https://pubs.usgs.gov/tm/2005/tm6A16/. Hydrogeologic Report New Madrona K‐8 Project Edmonds, Washington MODEL DOMAIN AND BOUNDARIES November 2016               21‐1‐22082‐003  SHANNON & WILSON, INC. Geotechnical and Environmental Consultants FIG. D‐1 250 5000 OW‐2 OW‐1 Northern Constant Head boundary (elev. 299 ft) Southern Constant Head boundary (elev. 300 ft)FI G .  D‐1 Observation well Hydrogeologic Report New Madrona K‐8 Project Edmonds, Washington PLANNED UIC WELLS November 2016               21‐1‐22082‐003  SHANNON & WILSON, INC. Geotechnical and Environmental Consultants FIG. D‐2 250 5000 UIC Area 1 UIC Area 4 UIC Area 3 UIC Area 2 Mo d e l  Do m a i n FI G .  D‐2 Planned UIC Well Hydrogeologic Report New Madrona K‐8 Project Edmonds, Washington MODEL MESH IN NORTHERN UIC  WELLFIELD AREA November 2016               21‐1‐22082‐003  SHANNON & WILSON, INC. Geotechnical and Environmental Consultants FIG. D‐3 100 2000 UIC Area 1 UIC Area 2 UIC Area 3 FI G .  D‐3 Planned UIC Well Hydrogeologic Report New Madrona K‐8 Project Edmonds, Washington MODEL SECTIONS NORTH‐SOUTH &  WEST‐EAST THROUGH WELL IW‐2 November 2016               21‐1‐22082‐003  SHANNON & WILSON, INC. Geotechnical and Environmental Consultants FIG. D‐4 Northern Constant  Head boundary (elev. 299 ft) Southern Constant  Head boundary (elev. 300 ft) Well  OW‐2 250 5000 Low K layer Low K layer Qva aquifer Qva aquifer Vertical  exaggeration = x2 Unsaturated Qva unit Unsaturated Qva unit Well  OW‐2 FI G .  D‐4 South North EastWest 225’ 225’ 293’ 293’ 455’ El e v a t i o n El e v a t i o n 400’ Madrona Model App D tables and figures - sdt 11-16-16 11/23/2016 1. Observation point locations shown on Figure 10 2. Input hydrograph provided by KPFF FI G . D - 5 November 2016 21-1-22082-003 FIG. D-5 Notes: Hydrogeologic Report New Madrona K-8 School Edmonds, Washington MODEL INPUT HYDROGRAPH & PREDICTED GROUNDWATER LEVELS AT UIC AREAS - BASE CASE SHANNON & WILSON, INC. Geotechnical and Environmental Consultants 0 500 1000 1500 2000 295 300 305 310 315 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 Ho u r l y F l o w I n p u t R a t e ( g p m ) Gr o u n d w a t e r E l e v a t i o n ( f t ) Time (hours) Input Hydrograph OBS-1 (UIC Area 1)OW-2 (UIC Area 2) OBS-3 (UIC Area 3)OBS-4 (UIC Area 4) Madrona Model App D tables and figures - sdt 11-16-16 11/23/2016 1. Observation point locations shown on Figure 10 2. Input hydrograph provided by KPFF 3. OW-2 elev = 445 feet; OBS-5 = elev. 444 ft; OBS-6 = elev. 450 ft; OBS-7 = elev. 370 ft Hydrogeologic Report New Madrona K-8 School Edmonds, Washington Notes: PREDICTED GROUNDWATER LEVELS ALONG TRANSECT THROUGH UIC AREA 2 - BASE CASEFI G . D - 6 November 2016 21-1-22082-003 FIG. D-6SHANNON & WILSON, INC. Geotechnical and Environmental Consultants 0 500 1000 1500 2000 295 300 305 310 315 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 Ho u r l y F l o w I n p u t R a t e ( g p m ) Gr o u n d w a t e r E l e v a t i o n ( f t ) Time (hours) Input Hydrograph OW-2 (UIC Area 2) OBS-5 (70 ft west of OW-2) OBS-6 (100 ft west of OW-2) OBS-7 (400 ft west of OW-2) Madrona Model App D tables and figures - sdt 11-16-16 11/23/2016 1. Observation point locations shown on Figure 10 2. Input hydrograph provided by KPFF Hydrogeologic Report New Madrona K-8 School Edmonds, Washington Notes: MODEL INPUT HYDROGRAPH & PREDICTED GROUNDWATER LEVELS AT UIC AREA 2 - SENSITIVITY CASESFI G . D - 7 November 2016 21-1-22082-003 FIG. D-7SHANNON & WILSON, INC. Geotechnical and Environmental Consultants 0 400 800 1200 1600 2000 290 300 310 320 330 340 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 Ho u r l y F l o w I n p u t R a t e ( g p m ) Gr o u n d w a t e r E l e v a t i o n ( f t ) Time (hours) Input Hydrograph Base Case (OW-2)Sensitivity Case 1 Sensitivity Case 2 Sensitivity Case 3 Madrona Model App D tables and figures - sdt 11-16-16 11/23/2016 1. Observation point locations shown on Figure 10 2. Input hydrograph provided by KPFF 3. OW-2 elev = 445 feet; OBS-5 = elev. 444 ft; OBS-6 = elev. 450 ft; OBS-7 = elev. 370 ft Hydrogeologic Report New Madrona K-8 School Edmonds, Washington Notes: PREDICTED GROUNDWATER LEVELS ALONG TRANSECT THROUGH UIC AREA 2 - SENSITIVITY CASE 3FI G . D - 8 November 2016 21-1-22082-003 FIG. D-8SHANNON & WILSON, INC. Geotechnical and Environmental Consultants 0 500 1000 1500 2000 310 315 320 325 330 335 340 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 Ho u r l y F l o w I n p u t R a t e ( g p m ) Gr o u n d w a t e r E l e v a t i o n ( f t ) Time (hours) Input Hydrograph OW-2 (UIC Area 2) OBS-5 (70 ft west of OW-2) OBS-6 (100 ft west of OW-2) OBS-7 (400 ft west of OW-2) 21-1-22082-003 APPENDIX E IMPORTANT INFORMATION ABOUT YOUR GEOTECHNICAL/ENVIRONMENTAL REPORT Page 1 of 2 1/2016 SHANNON & WILSON, INC. Geotechnical and Environmental Consultants Attachment to and part of Report 21-1-22082-003 Date: November 29, 2016 To: Ms. Taine Wilton Edmonds School District #15 IMPORTANT INFORMATION ABOUT YOUR GEOTECHNICAL/ENVIRONMENTAL REPORT CONSULTING SERVICES ARE PERFORMED FOR SPECIFIC PURPOSES AND FOR SPECIFIC CLIENTS. Consultants prepare reports to meet the specific needs of specific individuals. A report prepared for a civil engineer may not be adequate for a construction contractor or even another civil engineer. Unless indicated otherwise, your consultant prepared your report expressly for you and expressly for the purposes you indicated. No one other than you should apply this report for its intended purpose without first conferring with the consultant. No party should apply this report for any purpose other than that originally contemplated without first conferring with the consultant. THE CONSULTANT'S REPORT IS BASED ON PROJECT-SPECIFIC FACTORS. A geotechnical/environmental report is based on a subsurface exploration plan designed to consider a unique set of project-specific factors. Depending on the project, these may include: the general nature of the structure and property involved; its size and configuration; its historical use and practice; the location of the structure on the site and its orientation; other improvements such as access roads, parking lots, and underground utilities; and the additional risk created by scope-of-service limitations imposed by the client. To help avoid costly problems, ask the consultant to evaluate how any factors that change subsequent to the date of the report may affect the recommendations. Unless your consultant indicates otherwise, your report should not be used: (1) when the nature of the proposed project is changed (for example, if an office building will be erected instead of a parking garage, or if a refrigerated warehouse will be built instead of an unrefrigerated one, or chemicals are discovered on or near the site); (2) when the size, elevation, or configuration of the proposed project is altered; (3) when the location or orientation of the proposed project is modified; (4) when there is a change of ownership; or (5) for application to an adjacent site. Consultants cannot accept responsibility for problems that may occur if they are not consulted after factors which were considered in the development of the report have changed. SUBSURFACE CONDITIONS CAN CHANGE. Subsurface conditions may be affected as a result of natural processes or human activity. Because a geotechnical/environmental report is based on conditions that existed at the time of subsurface exploration, construction decisions should not be based on a report whose adequacy may have been affected by time. Ask the consultant to advise if additional tests are desirable before construction starts; for example, groundwater conditions commonly vary seasonally. Construction operations at or adjacent to the site and natural events such as floods, earthquakes, or groundwater fluctuations may also affect subsurface conditions and, thus, the continuing adequacy of a geotechnical/environmental report. The consultant should be kept apprised of any such events, and should be consulted to determine if additional tests are necessary. MOST RECOMMENDATIONS ARE PROFESSIONAL JUDGMENTS. Site exploration and testing identifies actual surface and subsurface conditions only at those points where samples are taken. The data were extrapolated by your consultant, who then applied judgment to render an opinion about overall subsurface conditions. The actual interface between materials may be far more gradual or abrupt than your report indicates. Actual conditions in areas not sampled may differ from those predicted in your report. While nothing can be done to prevent such situations, you and your consultant can work together to help reduce their impacts. Retaining your consultant to observe subsurface construction operations can be particularly beneficial in this respect. Page 2 of 2 1/2016 A REPORT'S CONCLUSIONS ARE PRELIMINARY. The conclusions contained in your consultant's report are preliminary because they must be based on the assumption that conditions revealed through selective exploratory sampling are indicative of actual conditions throughout a site. Actual subsurface conditions can be discerned only during earthwork; therefore, you should retain your consultant to observe actual conditions and to provide conclusions. Only the consultant who prepared the report is fully familiar with the background information needed to determine whether or not the report's recommendations based on those conclusions are valid and whether or not the contractor is abiding by applicable recommendations. The consultant who developed your report cannot assume responsibility or liability for the adequacy of the report's recommendations if another party is retained to observe construction. THE CONSULTANT'S REPORT IS SUBJECT TO MISINTERPRETATION. Costly problems can occur when other design professionals develop their plans based on misinterpretation of a geotechnical/environmental report. To help avoid these problems, the consultant should be retained to work with other project design professionals to explain relevant geotechnical, geological, hydrogeological, and environmental findings, and to review the adequacy of their plans and specifications relative to these issues. BORING LOGS AND/OR MONITORING WELL DATA SHOULD NOT BE SEPARATED FROM THE REPORT. Final boring logs developed by the consultant are based upon interpretation of field logs (assembled by site personnel), field test results, and laboratory and/or office evaluation of field samples and data. Only final boring logs and data are customarily included in geotechnical/environmental reports. These final logs should not, under any circumstances, be redrawn for inclusion in architectural or other design drawings, because drafters may commit errors or omissions in the transfer process. To reduce the likelihood of boring log or monitoring well misinterpretation, contractors should be given ready access to the complete geotechnical engineering/environmental report prepared or authorized for their use. If access is provided only to the report prepared for you, you should advise contractors of the report's limitations, assuming that a contractor was not one of the specific persons for whom the report was prepared, and that developing construction cost estimates was not one of the specific purposes for which it was prepared. While a contractor may gain important knowledge from a report prepared for another party, the contractor should discuss the report with your consultant and perform the additional or alternative work believed necessary to obtain the data specifically appropriate for construction cost estimating purposes. Some clients hold the mistaken impression that simply disclaiming responsibility for the accuracy of subsurface information always insulates them from attendant liability. Providing the best available information to contractors helps prevent costly construction problems and the adversarial attitudes that aggravate them to a disproportionate scale. READ RESPONSIBILITY CLAUSES CLOSELY. Because geotechnical/environmental engineering is based extensively on judgment and opinion, it is far less exact than other design disciplines. This situation has resulted in wholly unwarranted claims being lodged against consultants. To help prevent this problem, consultants have developed a number of clauses for use in their contracts, reports, and other documents. These responsibility clauses are not exculpatory clauses designed to transfer the consultant's liabilities to other parties; rather, they are definitive clauses that identify where the consultant's responsibilities begin and end. Their use helps all parties involved recognize their individual responsibilities and take appropriate action. Some of these definitive clauses are likely to appear in your report, and you are encouraged to read them closely. Your consultant will be pleased to give full and frank answers to your questions. The preceding paragraphs are based on information provided by the ASFE/Association of Engineering Firms Practicing in the Geosciences, Silver Spring, Maryland