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£� 011, �. v V- i and for BTEX by EPA Method 8020. Table 2 summarizes the analytical results of groundwater sampling from September 1986 to May 199I. Table 3 summarizes the well gauging and LPPH monitoring from August 1987 to May 1991. 2.6 BAIL TESTS In October 1988,EA conducted several bail tests in the wells on the site in anticipation of their use as recovery wells(EA 1989). Four wells (MW 1,MW2,MW3,and MW6)were tested. The tests were accomplished by quickly extracting 2.1 gallons of water using a PVC bailer and allow- ing the aquifer to rebound to its initial water level. Recovery data were monitored and collected with a HERMIT Model SE 100013 Environmental Data Logger and a 10-psi pressure transducer. The transmissivity value for each test was esti- mated using the Well Hydraulic Interpretation Program(WHIZ') of Hydro-Geo Chem.,Inc. The average values of transmissivity(T)ranged from 10.9 (MW6) to 80 ft2/day (MW3) (Table 4); values of hydraulic conductivity calculated front these values ranged from about 3 ft/day(MW6) to 28 ft/day(MW3). The results obtained from wells MW3 and MW6 were probably affected by the presence of LPPI-I in those wells: a decrease in transmissivity in three consecutive tests of MW3,from 80 to 12 ft2/day,might have been caused by fuel replacing the,water in the pores of the soil and gravel pack around the well when bailing lowered the water level, decreasing the ability of soil and sand to conduct water. In addition, screen slots covered with petroleum hydrocarbons can considerably decrease a well's efficiency and affect the results of the test. Values of transmissivity and hydraulic conductivity derived from these tests are in Table 4. On 3I May 1990 several bail tests were conducted in the new monitoring/recovery wells to determine hydraulic properties of this deeper saturated zone and potential capacity of the wells. Bail test results are presented in Table 4. 2.7 PUMPING AND INJECTION TESTS To better determine the hydraulic properties of the saturated zone under former Exxon RS 7-3142 and to more accurately size the treatment system,EA conducted pumping tests in wells RW 1 and RW2, On 18 September 1990 a preliminary pump test was conducted in well RW 1 to establish a sus- tainable pumping rate for this well. The test lasted about 1.2 hours and determined that a pump- ing rate of 3.6 gpm should be used for the actual pump test. Wells RW2 and RW3 were moni- tored during the preliminary test, but no significant drawdown (move than 0.01 feet) was ob- served. The total drawdown observed in well RW 1 during this initial test was 6.26 feet. On 19 September,a long-term pumping test was conducted in well RWI; a submersible pump pumped from the well to a temporary storage tank. The test was started at 0804 hours, after all c62/..Q7394Vj-91A. 4