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Mr. Ron Rowe November 24, 1997 Page 2 �. to Superior Analytical Laboratory(Superior)in Martinez,California,a state-certified laboratory with a completed chain-of-custody record. Six soil samples were analyzed for total petroleum hydrocarbons as gasoline(TPHg) and benzene, toluene, ethylbenzene, and xylenes (BTEX) and methyl tertiary butyl ether (MTBE) by EPA Methods 8015(modified)and 8020,respectively. Two soil samples were analyzed by North State Environmental (North State)in South San Francisco,California for methanol,ethanol,tertiary butyl alcohol(TBA),MTBE,di isopropyl ether (RIPE), ethyl tertiary butyl ether (ETBE), and tertiary amyl methyl ether (TAME) by EPA Method 8260. The laboratory analytical results for the analyses are included in Table 1 and the laboratory analytical reports and chain-of-custody records are included as Attachment A. Four soil samples were selected for physical analyses and were delivered to Cooper Testing Laboratories (Cooper)in Mountain View,California,with a completed chain-of-custody record. Each of the four samples were tested for porosity,bulk density,moisture content,and fraction organic carbon. Vertical permeability testing was initially proposed;however,due this test could not be performed because the sample tubes were not the correct diameter. The results of the physical analyses are included in Table 2 and the laboratory analytical reports and chain-of-custody records are included as Attachment A. Discrete,grab,groundwater samples were collected froth the soil boring at two depths. After the driller reported the first encountered ,groundwater upon reaching the borehole depth of 35 feet, the hollow-stem augers were pulled up approximately five feet to allow groundwater to enter the borehole. The grab groundwater sample was then collected through the augers using a disposable bailer. A second discrete groundwater sample was collected by driving a Hydropunch sampling toot to a depth of 44 feet, exposing the Hydropunch screen from approximately 41 to 44 feet bgs,and using a clean stainless steel bailer to collect groundwater from within the Hydropunch sampler. Both groundwater grab samples were transferred directly from the bailers into laboratory- supplied glassware, labeled, sealed in plastic bags, and placed in a cooler containing ice. Samples were transported to Superior along with completed chain-of-custody records and were analyzed for TPHg and BTEX and MTBE by EPA Methods 8015, modified and 8020, respectively. The groundwater samples were also analyzed by North State for methanol,ethanol,TBA,MTBE,DIPE,ETBE,and TAME by EPA Method 8260. The laboratory analytical results are included in Table 1 and the laboratory analytical reports and chain-of- custody hain-ofcustody records are included in Attachment A. Well Installation,Development,and Sampling After rheeming the original 85 foot borehole to the total depth of 90 feet using 10-inch augers, the borehole (MW-7)was converted to a dual completion groundwater monitoring well. Detailed well construction designs are included with the boring log(Attachment B). Groundwater monitoring well MW-7-D was completed at a depth of 85 feet bgs with 5 feet of capped, flush- threaded,2-inch diameter Schedule 40 PVC 0.020-inch machine slotted well screen from the base of the borehole and completed with blank casing to the surface. Filter sand was placed in the annular space between the wall of the borehole and casing to a height of three feet above the screened interval. Two feet of coated bentonite pellets were placed above the sand. A volclay-grout was placed into the remaining annular space to 67 feet bgs followed by another 2 feet of coated bentonite pellets and 2 feet of filter pack sand. Groundwater monitoring well MW-7-S was completed at a depth of 63 feet bgs with 8 feet of capped,flush-threaded,2-inch diameter Schedule 40 PVC 0.020-inch machine slotted well screen from 63 feet bgs and completed with blank casing to the surface. Filter sand was placed in the annular space between the wall of the borehole and two casings(wells MW-7-S and MW- 7-D)from 65 feet bgs to one and a half feet above the screened interval. Two and a half feet of bentonite pellets were placed above the sand and hydrated. A cement-grout mixture(5%bentonite)was placed into the remaining annular space to ground surface. A flush-mounted,protective water-tight monument cover was then grouted slightly above ground surface to complete the well installation. Both of the dual completion wells were fitted with locking water-tight well caps. H:1.SPFBISTOCKTONIW KP2.RPT