SITE INFORMATION AND CORRESPONDENCE FILE 2

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• Former George's Service Page 2 1600 Durham Ferry Road August 22, 2014 Tracy, California 95376 • Observe soil samples for moisture content, and petroleum hydrocarbon contamination by noting soil discoloration and recording readings from a photo ionization detector (PID) used to detect petroleum hydrocarbon concentrations. The EHD and GZA have discussed GZA's proposals presented in the work plan during a telephone conversation on 04 August 2014. Consideration was given to the limited vadose zone since first groundwater is currently at approximately fourteen-and-a-half feet bsg. The EHD and GZA concluded that an AS/SVE pilot test should be performed and based on the findings, the pilot test may be followed by submittal of a Corrective Action Plan (CAP) by GZA. To this end, the EHD approves the installation of only one of the two proposed AS wells and only four of the eight proposed SVE wells. Specifically, the EHD approves the installation of the proposed AS and SVE wells that are clustered under the northern section of the building as illustrated on Figure 3 of the work plan. The EHD also approves the advancement of the three proposed soil borings for site assessment, collection of the proposed soil samples from the three borings, one AS and four SVE wells for lithologic and chemical analyses, and field observations as presented in the above-bulleted items. The EHD directs that an AS/SVE pilot study work plan be submitted to this agency by 17 October 2014 that defines the AS/SVE parameters to be collected and duration of the pilot test. Proceed with installing the one AS and four SVE wells and advancing the three soil borings. Submit a Well and Boring Permit Application, Licensed Contractors' Declaration (LCD) form, Master File Record (MFR) form, and appropriate permit/inspection fees to the EHD. Please note that the EHD fees have increased effective 01 August 2014. The permit fee for the installation of each well is $130; the total fee for all three borings is $130; and the Inspection/Activity fee is $390 per parcel. A fee of$1,170.00 ($130 x 5 + $130 + $390) will be required for the well installation and borings. In 15t Semi-Annual Groundwater Monitoring & Remedial Effectiveness 15t & 2"d Quarters 2014, dated 04 August 2014, GZA recommends performing "quarterly depth-to-water measurements from wells MW-101, MW-201, MW-107, MW-2x and MW-202 in order to calculate vertical groundwater gradients as requested in the SJCEHD letter dated June 4th, 2014." To clarify, by letter dated 04 June 2014, the EHD recommended dispensing with the time and effort to calculate and report vertical gradient as the information derived is fairly redundant and does not appear to be needed for proper management of the plume of impacted groundwater. If GZA can demonstrate that significant changes in the vertical gradient are likely to occur and that the information is required to make specific adjustments in managing the groundwater contaminant plume, then EHD will reconsider this recommendation. The EHD approves continuation of: • Bi-monthly AS/SVE system operation and monitoring activities of the existing system; • Monthly groundwater monitoring of selected wells to assess the performance and effectiveness of the existing AS/SVE system; • Quarterly groundwater monitoring and sampling that includes an annual event and three quarterly remedial performance groundwater monitoring events; and