Laserfiche WebLink
d <br /> Guardino and Crawford <br /> ji 517 West Fremont <br />,i Page 2 <br /> 9.6 ug/1 of benzene, and 1. 6 ug/1 of MTBE. Additional investigation to define the lateral <br /> and vertical extent of the groundwater contamination is required. <br /> The southern extent of the shallow zone of contamination is also not fully defined. <br /> Although the grab groundwater sample of P4 was non-detect, the P4 grab groundwater <br /> sample was collected in 1997, and the analytical results of the grab groundwater sample of <br /> P11 collected in 2000 were 660 ug/I TPH-g, 5.3 ug/1 MTBE, and 22 ug/1 tertiary butanol <br /> (TBA) . The sample in P4 is too far from Pl l and MW-5 to be considered as the southern <br /> delineation of the groundwater contamination. In addition a relatively large data gap (about <br /> 80 feet) exists between 1AW-1, MW-3, and MW-4. Since groundwater flow direction is to <br /> the northeast, additional investigation off-site is required to delineate the groundwater <br /> contamination in the northeast direction. <br /> Submit a wotk plan that will delineate the vertical extent and the lateral extent of the <br /> groundwater contamination to EHD by July 31, 2004. <br /> If you have any questions, please contact Jeffrey Wong at (209) 468-0335. <br /> Donna Heran, REHS, Director <br /> Environmental Health Department <br /> w <br /> Jeffrey Wong, Senior REHS Margo 'o, i <br /> LOP/Site Mitigation Unit N Supervisor <br /> c: RWQCB, Central Valley Region —James L. L. Barton, RG <br /> c: Advanced GeoEnvironmental, Inc. — Daniel W. Kalmbach <br />;I <br />