SITE INFORMATION AND CORRESPONDENCE FILE 2

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0aw '% " California Tank Lines, Inc. Page 2 of 3 3105 South EI Dorado Street November 6, 2014 Stockton, California 95206 • Submittal of up to twenty-four soil samples for analysis of total petroleum hydrocarbons (TPH) as gasoline (TPHg), TPH as diesel (TPHd) and TPH as motor oil (TPHo); and submittal of one soil sample that exhibits the highest TPHg concentrations from each boring for analysis of benzene, toluene, ethylbenzene and total xylenes (BTEX); methyl tertiary-butyl ether (MTBE), ethyl tertiary-butyl ether (ETBE), tertiary-amyl methyl ether (TAME), di-isopropyl ether (DIPE) and tertiary-butyl alcohol (TBA); • Installation of two wells (DW-6 and DW-7) on the west side of South EI Dorado Street using four-inch-diameter polyvinyl chloride (PVC) casing and one well (DW-8) on the east side of South EI Dorado Street using two-inch-diameter PVC casing with screen intervals between approximately twenty and thirty-five feet bsg in all three wells, dependent on geologic/hydrogeologic conditions encountered during drilling; • Following the installation of the well casing, construction of the wells with a gravel pack placed in the annular space from total depth of the boring to two feet above the 0.020- inch slotted PVC casing, followed by development of the well using a surge block, then installation and hydration of three feet of bentonite chips, followed by installation of bentonite grout from above the bentonite chips to three feet bsg; • Collection of groundwater samples quarterly from the three newly installed wells (DW-6, DW-7 and DW-8) and five existing wells for analysis of TPHg, TPHd, TPHo, BTEX, MTBE, ETBE, TAME, DIPE and TBA; (If product is present in the groundwater, the well will not be purged and a grab groundwater sample will be collected under the product for analysis of TPHg, TPHd, TPHo, BTEX, MTBE, ETBE, TAME, DIPE and TBA.) • Survey of the existing and newly-installed wells and update of the site map based on the survey data; and • Submittal of Site Assessment Report prepared by DES that includes all documentation signed by facilities receiving waste generated during the well installations. The EHD approves the work plan with the following conditions: • Submittal of soil samples collected at five and ten feet bsg from each of the three borings for analysis of TPHg, BTEX and MTBE if justified by odor, staining or elevated organic vapor readings; • Hydrate the bentonite chips for at least thirty minutes before installing the grout; • "Bentonite grout" may only contain five percent bentonite; the EHD prefers using neat cement; • Quarterly monitor and sample only the three newly-installed wells and only for one year; the existing wells should be monitored and the groundwater collected for analysis based on the EHD directives by letters dated 9 September 2014, and 30 October 2013; and • Identification of the three new wells as MW-6, MW-7 and MW-8 instead of DW-6, DW-7 and DW-8 for consistency in well nomenclature and the elimination of future potential confusion of these wells for domestic wells or deep wells.