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q The wells of concern are MW3, MW4, and MWS, where the depth-to- bottom measurements are between 57.35 and 59.6 feet. Low water levels over the period July 1989 - February 1990 had made it impossible to sample any water from MW4 and MW5. 'yells MW1 , MW2, and MW3 were all sampled in July 1989 and December 1989 (Table 1 ) . EA personnel visited the site on 7 February and agaiL on 14 February 1990. Gauging data from these site visits indicate that MW4 and MW5 now contain water. Water levels at the site have i risen so that the current ( 14 February 1990) depth to water at the site is 56-57 feet below� the surface (Appendix B) . In the week that passed between the two si e 7vsits, there was a 0. 1 foot increase in groundwater elevation in all wells. It appears that groundwater levels in Stockton are rising again after i reaching a low point in the summer of 1989 (Table 2) : Groundwater samples were collected from all five of the wells on the site , on 14 February. Wells MW1 , MW2; and MW3 all contained € enough water to bero erl 1 A P Y purged before the samples were Col- lected. Wells .MW4 and MW5 could not be properly purged before sample collection, as the water column was too short and the wells did not recharge at- a fast enough rate for the hand bailing method to .be effective. EA personnel will continue to monitor the water level in the wells on a weekly� basis. If the groundwater elevation: n continues to rise, there should be enough water in MW4 and MW5 to permit proper purging and sampling of these wells before the .end of the spring rains. EA will collect .water samples i p es from these wells as soon-as it_ is_possible -to -Properly-dorso. - - - As long as sufficient water remains, in the well screen to permit proper purging. procedure s, there may be an advantage to using the rS Present wells for groundwater monitoring. Recent studies have 41 suggested that the maximum contaminant concentrations inan r � . e35/71.050/2-90/tx 3 . ---