SITE INFORMATION AND CORRESPONDENCE_FILE 2

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Fremont Shell Station Page 2 of 3 2494 East Fremont Street June 18, 2014 Stockton, California 95205 Concurrent with the public participation period, please provide the EHD certification in writing that all record owners of fee title to the above-referenced site have been notified of your request for closure. This is in accordance with Section 25297.15 of the California Health and Safety Code. Submit a complete list of record owners of fee title and their mailing addresses to the EHD. A form has been enclosed for this purpose. Please submit the information at your earliest convenience. During the sixty-day public participation period, it is necessary to plan and prepare to execute the destruction of all wells installed as part of your site investigation and remedial action so that once responses received during the sixty-day public participation period have been properly addressed, well destructions can commence. Please submit a scope of work proposal that details the conditions and construction of the wells and the methods and materials to be used to destroy them. To be issued a well destruction permit, the proposal must address the concerns of the EHD and the San Joaquin County Well Standards requirements, such as: • Wells that have laboratory data from the last sampling event that demonstrate the presence of any contaminants of concern remaining in groundwater are to be destroyed by removing all the contents of the well [well casing (except steel conductor casing), screen, filter pack, grout sealant]; the cleared borehole is then to be sealed with neat cement from the bottom upward to the depth of three to five feet below grade. • Wells with unknown construction and/or located in an area of known or suspected contamination are to be destroyed by removing all the contents of the well [well casing (except steel conductor casing), screen, filter pack, grout sealant]; the cleared borehole is then to be sealed with neat cement from the bottom upward to the depth of three to five feet below grade. • Wells that have laboratory data from the last groundwater sampling event that report non- detectable concentrations of contaminants of concern and with acceptable laboratory detection limits, and are not in areas of known or suspected soil contamination, may be destroyed by pressure grouting from the bottom upward, while leaving the well casing in place. The top three feet or more of the well shall be drilled out with an auger that is at least one foot larger in diameter than the auger originally utilized to install the well, and the soil around the cut-off casing removed to the depth of an additional six inches below the new `top' of the cut-off casing. The grout sealant shall spill out of the top of the well casing to form a mushroom cap seal with at least twelve inches of neat cement grout poured six inches above and six inches below the top of the cut-off casing. • All groundwater displaced to the surface during grout installation shall be pumped out of the excavation to allow for EHD inspection and verification that the well has been properly destroyed. Contaminated groundwater pumped out of the excavation shall be containerized for proper disposal.