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i Number 3 Monterey sand was used as filter pack and was placed to extend from the bottom of =h' the wells to approximately one foot above the screened interval in the annular space of each well (30-9 feet bsg). The bentonite seals at 9 to 71/z feet bsg were hydrated with five gallons of potable water. Portland cement was pumped into the remaining annular space above the bentonite seals to extend from 71/2 feet to 1 foot bsg in each well. Locking caps were placed on top of the well casings inside 8-inch, water-tight street boxes cemented into place at the surface. Monitoring wells MW-4, MW-5, and MW-6 were developed on June 20, 1994 using a stainless steel bailer. Bailing removed turbid water from the wells until clear water appeared. The monitoring wells were sampled after a minimum of 50 gallons were bailed and the ground-water levels had recovered to at least 90% of their static levels. Monitoring wells MW-4, MW-5, and MW-6 were first sounded on June 24, 1994. Utilizing a Keck' interface probe, the W.W. Irwin, Inc. staff technician intercepted the piezometric surface in each well at a depth averaging 14.82 feet bsg. The soundings were converted using well casing-top elevations established on June 13, 1994 by Duane Kimball, a Modesto-based, California-licensed land surveyor. The elevation data were used to calculate the present ground- water flow direction and gradient by the three-point method. Ground-water samples collected from MW-4, MW-5, and MW-6 were received at Sherwood Labs on June 21, 1994. The analytical results revealed wholly nondetectable concentrations of TRPH-d analytes and nondetectable results for TPH-g and BTEX analytes in samples collected = � from wells MW-4 and MW-5. The results of the analysis of the sample collected from MW-6 V- indicated that the ground water underlying that vicinity was significantly impacted with TPH-g and BTEX analytes well above the Maximum Contamination Levels (MCLS) set by the California Department of Health Services. 2.4 Interim Ground-Water Monitoring Activities The SJCPHS EHS then required that ground-water monitoring be undertaken for six months, from August 1994 through January 1995. Samplings of MW-4, MW-5, and MW-6 were performed in September and December of 1994. Soundings were performed monthly. Local tidal influences (clock-times and heights) at Stockton were converted monthly from available tidal table information on the dates of soundings of the three wells. The Project Status Report of Ground-Water Monitoring (W.W. Irwin, Inc., January 30, 1995) contained data which, until now, was the most recent regarding site conditions at Village West Marina. W.W. bwin, Inc. f. :• Project No. 33016.05&.06 ' August 1995 5