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MW-4 will be installed approximately 160 feet north of the Quality Cleaners in the general area of Partner's May 2015 groundwater sample from boring B7-GW. This well is intended to be a downgradient/cross gradient groundwater monitoring well. MW-5 will be installed approximately 180 feet northeast of the Quality Cleaners in the general area of Partner's May 2015 groundwater sample from boring B8-GW. This well is intended to be a downgradient groundwater monitoring well. It is anticipated that the depth of the bottom of the well screens will be 20 to 25 feet bgs. The two-inch diameter wells will be constructed of Schedule 40 PVC and will be placed in a six-inch diameter borehole drilled with a hollow-stem auger drill rig. The screen slot-size will be 0.020 inch and the top of screens will be at an interval above the water table that will allow for an annular seal with a minimum thickness of at least five feet. The screen intervals will be determined in the field but will not exceed 15 feet and will not cross connect different hydrologic units based on logging of the soil borings in the field. If stratum within the saturated material below the water table consisting of distinctly finer grained soil that appears to separate over and underlying coarser-grained soil, the vertical location of the screened interval will be modified such that the screened interval is overlying the finer grained stratum. A filter pack, consisting of rounded, Monterey No. 3 sand (washed and bagged at one cubic foot per sack) will be placed into the annular space to a depth of approximately one foot above the top of the screen. The groundwater in the wells will be agitated with a surge block to settle the sand pack by flushing the fine grained sediments from the sand pack. A one-foot-thick seal, consisting of dry bentonite pellets, will be placed above the filter pack. The remaining annular space will be filled with neat cement grout. A flush-mounted, traffic-rated well vault will be emplaced to provide access to the wellheads. The well vaults will be set above existing site grade to promote positive drainage away from the wellhead. Equipment used for the advancing of the soil borings and the sampling of soils will be decontaminated (steam-cleaned, TSP, lab-grade detergents, etc.) before arriving on Site between each boring and sampling, and before leaving the Site each day, or as necessary to reduce the chances of cross- contamination. The decontamination fluids (rinsate) will be temporarily contained in Department of Transportation (DOT)-approved, appropriately labeled, steel 55-gallon sealable drums. The rinsate would be stored on-site and disposed pending analytical results using the procedure described above for transport and disposal of IDW. The monitoring wells will be developed with a vented surge block, and a bailer. The development will be conducted until each well is producing relatively sand-free groundwater with limited turbidity. Groundwater generated during well development will be temporarily stored in DOT-approved steel 55- gallon drums. The handling and disposal of well development water will be conducted in accordance with the procedures described for decontamination fluids and other IDW. 5.5.1 Proposed Groundwater Sampling Methodology Groundwater samples will be collected from the wells in approximately 48 hours following well development. Prior to collecting groundwater samples, The wells will be purged using a reduced-flow Sampling and Analysis Plan Tracy Corners Shopping Center 3225 North Tracy Boulevard Tracy,California 95376 Partner Project Number SM14-129814 Docket Number HAS-VCA 14/15-108 August 15,2016 Page 18