SITE INFORMATION AND CORRESPONDENCE FILE 1

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i California Tank Lines, Inc. Page 2 3105 South EI Dorado Street July 21 , 2010 Stockton, California 95206 The EHD approves the submittal of an evaluation of the potential for natural attenuation to degrade petroleum hydrocarbon contaminants in the area of MW-4. Taber proposes to use the data collected during the advancement of cone penetration test (CPT) borings P-1 through P-4 and S-5 in October 2007 in this assessment; however, report this evaluation as part of a corrective action plan (CAP) that includes evaluations of several methods for site remediation . The EHD had directed the submittal of a CAP by letters dated 12 January 2009 , and 03 March 2010, and directed that contaminant mass estimates , supported by calculations, for sorbed and dissolved TPH quantified as gasoline (TPH-G ), benzene , 1 ,2-dichloroethane (1 ,2-DCA), TPH-D, and TPH quantified as motor oil (TPH-MO) be included in the CAP as well as an analysis for cost-effectiveness for recommended remedial technologies . To date, the EHD has not received the CAP and now directs that the CAP be submitted by 01 November 2010. The EHD approves the advancement of two proposed soil borings to total depth of approximately 50 feet bsg , one north and one south of MW-4 as illustrated on Figure 3 of Work Plan. Soil samples will be collected at five-foot intervals for litholgical evaluation and screened in the field for visual signs of petroleum hydrocarbon contamination and for volatile organic compounds using an organic vapor meter with a photo-ionization detector. One grab groundwater sample will be collected from each borehole and analyzed for benzene , toluene, ethylbenzene, and total xylenes (BTEX), TPWG , TPH-D, TPH-MO, methyl tertiary-butyl ether (MTBE) , tertiary-amyl methyl ether (TAME), tertiary-butyl alcohol (TBA) , di-isopropyl ether (DIPE) , and 1 ,2-DCA. (Based on the boring logs generated at this site, please confirm with the driller that a Geoprobe® is capable of advancing to a total depth of approximately 50 feet bsg on this site and , if necessary, modify the drilling method in Work Plan.) Please submit an encroachment permit issued by the City of Stockton for the advancement of the two proposed borings in the City right-of-way on the west side of EI Dorado Street, along with a boring permit application and permit/inspection fee of $434 to the EHD and complete the fieldwork by 27 September 2010. Notify the EHD at least a week prior to the scheduled fieldwork. (Please note that the County will be raising permit and inspection fees effective 01 August 2010.) The EHD approves the use of specialized bailers and/or socks filled with Carphene or Peakwick to continuously remove the oil detected in MW-2. Begin immediately testing each of the proposed methods to determine the most effective for removing the oil from MW-2 and submit a report of findings to the EHD by 01 November 2010. Confirm the total depth of MW-1 during the next sampling event and redevelop this well if measurements indicate that there is a significant amount of silt at the bottom of this well. The EHD has reviewed the Sensitive Receptor Survey report dated 07 June 2010, in which three domestic wells are listed within a 2, 000 foot radius of this site . Of concern is the omission of eleven domestic wells previously reported within a 2, 000 foot radius of this site in Work Plan — Determination of the Extent of Contamination Affecting MW-4, dated 01 August 2006. Please notify the EHD if wells Dated at 3531 and 3060 Turnpike Road, 418 Downing Avenue., 2943 South Harris, 3267 McKinley Avenue , 646 South California Street, 3607 Harvey, and 3236 and 3377 Fairmont Avenue have been destroyed . Also, the EHD believes the closest surface water is Walker Slough and not McLeod Lake located approximately three miles north of the site.