SITE INFORMATION AND CORRESPONDENCE

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7-El Sven Store No. 17334 Page 2 of 3 4501 North Pershing Avenue December 2, 2013 Stockton, California 95207 and comment along with the list of agencies and owners/occupants who will receive the public participation letter. An example letter is available from the EHD, if requested. The public will have sixty days to comment. 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 )roperly 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 destrL ction permit, the proposal must address the concerns of the EHD and the San JoaqL in 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 are to be destroyed by removing all the contents of the well (conductor casing; well 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. • All 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 (conductor casing, well 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 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 form 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. • The EHD records indicate the presence of several 'nested' wells installed using ten- inch augers. The EHD has found destruction results of nested wells are best obtained when augers larger in diameter than the oriqinal augers are used and