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On April 13, 1999, John P. Cummings of JPCA after taking water <br /> depth measurements from each wells purged the wells by pumping <br /> and collecting the purged groundwater in 55-gallon drums labeled <br /> awaiting analysis. Each of the wells was pumped to dryness. The <br /> wells were slow in recovering as they were in the three previous <br /> sampling events. This phenomenon of slow recovery is most likely <br /> caused by the silty clay soil at the screened section of the <br /> wells. Well data sheets are contained in Appendix C. <br /> Groundwater samples, one from each well, was collected by a clean <br /> dedicated bailer, placed in two 40 ml VOAs with Teflon septa, <br /> labeled, held in a cooled (4 Degrees C) ice chest and transported <br /> to a State Certified Laboratory, under COC documentation, for <br /> analyses. The samples from Mw-1 , MW-2 and MW-3 were collected <br /> on April 13 , 1999 . <br /> The groundwater samples collected were analyzed for Total <br /> Petroleum Hydrocarbons as Gasoline (TPHG) ; Benzene, Toluene, <br /> Ethylbenzene and Xylene (BTEX) and Methyl-Tert-butyl ether <br /> (MTBE) . The groundwater samples were analyzed for TPHG by EPA <br /> Method 8015 modified with purge and trap preparation 5030 <br /> (GC/FID) with detection limits of 50ug/l . EPA Method 602 was <br /> utilized for BTEX with a detection limit of 0 . 5ug/1 as required <br /> by the SJCEHD. EPA Method 8260 was utilized for MTBE with a <br /> detection limit of 1.0 ug/l as required by the SJCEHD. <br /> The results of the analysis of the groundwater samples, collected <br /> on April 13, 1999 as a part of this file closure document, .in <br /> parts per billion (ppb) are shown in Table 6 . The laboratory <br /> data sheets with detection limits and COC documentation are <br /> contained in Appendix E. <br /> TABLE 6 <br /> April 13, 1999 Groundwater Sample Analysis Results in ppb. <br /> Sample TPHG MTBE B T E X <br /> MW-1 ND ND ND ND ND ND <br /> MW-2 300 ND 5 . 5 . 60 ND 2 . 4 <br /> MW-3 170 ND ND ND . 72 1. 5 <br /> ND = < 1 <br /> The cumulative groundwater results for all the analysis reported <br /> by JPCA of the groundwater samples in parts per billion (ppb) are <br /> shown in Table 7 . <br /> • 7 <br />