Laserfiche WebLink
vials and fitted with Te/7on7m-lined screw caps. Care was taken to ensure that no air space <br /> existed in the vials by inverting, tapping, and checking for bubbles. Each container was <br /> properly labeled in the field and refrigerated for transport to Sherwood Labs in Hilmar for TPH- <br /> g by EPA Method 503018015-mod; TRPH-d analysis by EPA Method 351018015-mod; and <br /> BTEX analytes by EPA Method 602. Appropriate chain-of-custody procedures were adhered <br /> to at all times during sample procurement and handling. The samples were extracted and <br /> analyzed within the lifespan limits set forth by EPA guidelines for the specified analyses. <br /> Samples of the surface waters in Fourteen-Mile Slough to the west of MW-6 were collected on <br /> January 13, 1995. The sampling methodology was similar to that utilized when sampling <br /> monitoring wells, except that a bailer was not used. The geologist filled the containers directly <br /> from the shore of the slough, just upgradient of MW-6 (see Figure 3F). Care was taken to <br /> ensure that no air space existed in the hand-filled vials by inverting, tapping, and checking for <br /> bubbles. Each container was properly labeled in the field and refrigerated for transport to <br /> Sherwood Labs in Hilmar for TPH-g by EPA Method 503018015-mod; TRPH-d analysis by EPA <br /> Method 351018015-mod;and BTEX analytes by EPA Method 602. Appropriate chain-of-custody <br /> procedures were adhered to at all times during sample procurement and handling. The samples <br /> were extracted and analyzed within the lifespan limits set forth by EPA guidelines for the <br /> specified analyses. <br /> 4.3 Analytical Results <br /> Ground-water samples collected from the five wells were received at Sherwood Labs on July 7, <br /> rsr 1995. The analytical results have revealed nondetectable concentrations of TRPH-d, TPH-g, and <br /> BTEX in samples collected from wells MW-4 and MW-5 on all sampling occasions; MW-7 and <br /> MW-8 have now also yielded unimpacted samples. The results of the analyses of the samples <br /> collected from MW-6 indicate that the ground water underlying that vicinity remains impacted <br /> with TPH-g and benzene analytes above the Maximum Contaminant Levels (MCLs) set by the <br /> California Department of Health Services. The analytical results for these sampling activities <br /> are summarized in Table 3. The Sherwood Labs analytical reports and chain-of-custody are <br /> included as Appendix E. <br /> W.W Irvin,Inc. <br /> —_ - Project No. 33016.05&.06 <br /> August 1995 12 <br />