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Phenols (EPA Method 604), polynuclear aromatic hydrocarbons (PAH) (EPA Method 610), and TPH/D None of these constituents were detected (Table 2) The monitoring wells installed by JHK were sampled by Dames & Moore in June 1988 and the samples analyzed for PAHs and TPHID No detectable constituents were reported During a subsequent sampling round in January 1989 only one well could be sampled, since the other two were dry, the water levels having dropped approximately 10 to 15 feet since the wells were installed in July 1987 The sample collected was analyzed for TPHID and VOCs No detectable constituents were reported The January 1989 sampling round was described in a letter report to the PHS-EHD (Dames & Moore, February 1989) The JHK wells were abandoned and four new groundwater monitoring wells (DMW-1, DMW-2, DMW-3, and DMW-4) were installed in July 1990 Following the workplan (Dames & Moore, April 1990) these wells were sampled in August 1990, December 1990, March 1991, and July 1991 Two reports describing these groundwater monitoring rounds have been submitted to the RWQCB (Dames & Moore, March 1991, and Dames & Moore, January 1992) Samples collected during these four rounds were analyzed for TPHID, VOCs, and PAHs No detectable levels of these constituents were reported (Table 2) 3 3 2 Groundwater Levels Groundwater levels elevations measured in the JHK and Dames & Moore monitoring wells during the eight rounds conducted between July 1987 and May 1994 are plotted and contoured in Figures 6 and 7 These figures show that groundwater gradients measured between July 1987 and July 1991 were very flat, from 0 0015 to 0 0019 feet per lmear foot, that the direction of the gradient tended towards the north/northwest Water level measurements from the four Dames & Moore monitoring wells in May 1994 show an even flatter gradient, 0 00056 feet per foot, in a westerly direction During that time there has been a net decrease in the groundwater level of about 26 feet This decline in water levels appears to be partly the result of a series of years of less than normal recharge to the groundwater system together with a general downward trend in groundwater levels regionally as a result of groundwater overdraft According to the San Joaquin County Flood Control and Water Conservation District, the eastern San Joaquin County Groundwater Bann has been under a condition of overdraft(groundwater withdrawal exceeding recharge) and water levels have been trending downward for several decades Superimposed on this downward trend are periods of temporary recovery followed by greater than normal rates of decline which occur during temporary periods of greater than normal and less than SAC116 47 6 AUGUST 1994 DAMES &MOORE