ARCHIVED REPORTS_REPORT SUMMARIZING INSTALL OF MONITORING WELLS MW4,MW5,MW7,MW8 & SOIL BORING RDM1 & 4TH QTR 2013 GROUNDWATER SAMPLING

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Ms. Angela Lee Humbrook Holdings,LLC February 12,2014 Page 4 Since groundwater monitoring was initiated at the site in September 2011, measured depth to groundwater in the monitoring wells has ranged from approximately 47 to 50 fbgs. Additional Soil and Groundwater Assessment Based on review of the results from previous environmental investigations performed at the site by other consultants, the following scope of work for additional soil and groundwater assessment was proposed in RDM's Workplan that was approved by the CVRWQCB in its letter dated February 13, 2013 (Enclosure B): • Installation of five offsite groundwater monitoring wells (MW-4 through MW-8) to further assess the lateral extent of the volatile organic compounds(VOC) groundwater plume; • Advance one soil boring immediately adjacent to the suspected former dispenser island; • Advance one cone penetrometer test(CPT)boring onsite to a depth of approximately 100 feet • below ground surface (fbgs) and grab one groundwater sample to further assess the vertical extent of the VOC groundwater plume; • Installation of two nested soil vapor extraction (SVE) wells (SVE-IA/B and SVE-2A/B), each screened from 10 to 25 fogs and 35 to 50 fogs, and one air sparge (AS) well (AS-1) screened from 63 to 65 fogs; • Conduct a 24-hour(12 hours on each nested SVE well) SVE pilot test and a 96-hour AS pilot test. Even though RDM's Workplan had already been approved by the CVRWQCB, our proposed scope of work had to be revised following budget review by the State Water Resources Control Board (SWRCB), Technical Review Unit of the Underground Storage Tank Cleanup Fund (USTCF). The USTCF issued a cost pre-approval letter, dated April 30, 2013, which denied RDM's requested budgets associated with remedial pilot testing (installation of the remedial testing wells SVE-1A/B, SVE-2A/B, and AS-1; remedial pilot testing activities; remedial testing results report; and preparation of a Corrective Action Plan (CAP)/remediation system design). In its letter dated May 22, 2013 (Enclosure B), the CVRWQCB addressed its concems/issues with the USTCF's April 30, 2013 cost pre-approval letter and directed RDM to perform a phased approach to the approved Workplan. In the phased approach, the CVRWQCB directed RDM to install a soil boring rather than a nested soil vapor extraction well at proposed location SVE-1A/B,beginning soil sampling at 5 fbgs and at 5-foot intervals until there was no evidence of contamination or until groundwater was present. It also requested RDM collect a grab groundwater sample from the soil boring. Based on the laboratory analytical results from this soil boring,the CVRWQCB would evaluate the data and determine if pilot testing was necessary, or whether the site may meet the State Water Resources Control Board's Low Threat Underground Storage Tank Case Closure Policy (LTCP) for No Further Action Required (NFAR)as a low-risk groundwater site. In addition to the revised scope of work discussed in the preceding paragraph, RDM was unable to install monitoring well MW-5 because the property owners (3201 East Main Street) failed to respond to RDM's numerous requests (both via mail and personal visits to the residence at 3201 East Main Street) for a right-of-entry agreement. RDM informed the CVRWQCB of the failure to get an approved right-of-entry agreement for MW-5. The CVRWQCB directed RDM to proceed with the other proposed work and based on the results of the groundwater analytical results for monitoring wells MW-4, MW-6 and MW-7, a future determination would be made as to whether MW-5 would need to be installed.