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well points, reaming out the temporary wells, and installing and sampling the ' permanent EMP monitoring wells. 4.4.1 Drilling, Logging, and Sampling ' Three permanent wells (MW-9A, MW-10A, and MW-11A) were constructed within the easement north and south of Interstate Highway 580 at the locations shown on Figure 3. 1 Construction practices were as approved in the EMP Workplan and in accordance with procedures summarized in Department of Water Resources Bulletin 74-90 (California 1 Well Standards) and the regulations outlined in the permit for well construction obtained from the San Joaquin Department of Environmental Health. All work was performed under the direct supervision and was documented by a California State Certified Engineering Geologist. Lithologic sampling and geologic logging followed the procedures used during Phase I field work (Section 4.2). Borehole drilling and well installation services were provided by Gregg Drilling. ' 4.4.2 Phase II Temporary Well Construction ' As with the Phase I temporary wells, once the Corcoran Clay was reached, the driller was instructed to advance the borehole five to ten feet below the first appearance of ' groundwater. A one-inch diameter Schedule 40 PVC casing with 0.010-inch slots was installed at this depth, and the borehole was backfilled with No. 2/12 sand until the perforated section of the casing was surrounded by the sand pack. A two- to three-foot ' thick bentonite chip seal was placed above the filter pack and hydrated with five gallons of water. The temporary wells were secured at the ground surface using a steel borehole cover weighted down with sand bags. ' 4.4.3 Phase II Temporary Well Sampling and Analysis Samples were collected from the Phase II temporary wells on February 24, 2012, to further assess the distribution of VOCs in groundwater. Grab samples were collected from each of the three Phase II temporary wells using disposable polyethylene bailers. At each well, the bailer was lowered down the temporary well casing using nylon twine. Once filled, the bailers were retrieved, and a bottom-emptying device was inserted into ' the bottom of the bailer to transfer the water into laboratory-supplied 40-milliliter (mL) VOAs with hydrochloric acid preservative. The filled VOAs were capped and then inverted to check for air bubbles, labeled, and then placed in a chilled cooler. After all ' samples were collected, the chain-of-custody form was completed, and the cooler was delivered to the laboratory courier for transport to the laboratory. ' Samples were analyzed for VOCs by EPA 8260B, and yielded the following results. EMP Report—Phase II Geo-Logic Page ■ 10 ' Corral Hollow Sanitary Landfill ASSOCIATES August 21,2012