SITE INFORMATION AND CORRESPONDENCE FILE 1

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a Fernando's Place 1201 S. Center St. Stockton, CA 95206 You and your consultant should discuss these reductions and reduction in sampling wells and chemical analysis should be days of the date of this letter. February 24, 2009 Page 2 others and a specific proposal for submitted to the EHD within 30 In correspondence dated July 21, 2005, the EHD concurred with your consultant's conclusion that the dissolved petroleum ground water plume was not vertically or laterally defined and in correspondence dated October 19, 2006, the EHD provided the following concerns they had with the site data: 1. A lack of vertical ground water plume delineation near MW -4 and MW -5; 2. A lack of lateral ground water plume delineation in all five hydrological units (HU), particularly toward the north and the east and toward the residential areas; 3. A lack of monitoring wells with screened intervals between 40 feet below ground surface (' bgs) and 100' bgs; 4. The potential for vapor intrusion to the nearby residences located around the site has not been evaluated. Some of those houses appear to have either half or full basements and are very close to monitoring wells with elevated levels of dissolved petroleum in the ground water; 5. The lack of sorbed and dissolved contaminant mass estimates for the site, and 6. The apparent instability of the dissolved plume. In the October 2006 correspondence the EHD also requested the submittal of cross sections that show ALL of the wells and screen intervals, with the lithological units identified in the boring logs correlated. The EHD is concerned that the monitoring of sand units that may serve as contaminant migration pathways has not been demonstrated. In addition, the EHD has some concerns with groundwater data from CMT well casings (currently installed at your site) at other sites and a satisfactory method of destroying these wells has not been found, so installation of single cased wells in the lithological units identified must be performed on future well installations. The above items must be addressed and a work plan should be submitted to the EHD within 45 days of the date of this letter that proposes the installation of additional monitoring wells. The soil vapor extraction/ground water extraction unit has still not been fully constructed (no electrical hookup) and a completion date has not been provided. The groundwater plume from your site is large, undefined and unstable and has high contaminant concentrations, so interim remediation is a necessity. The EHD directs you to complete the remedial unit installation and place the system online as soon as other agency approvals are given. You may direct your submittals and any questions 468-34549. -o you may have to Michael Infurna, at (209) Michael J. Infurna Jr., REHS Senior Registered Environmental Health Specialist Margar�o, RENS Program Coordinator ca James Barton, CVRWQCB Mark Owens, SWRCB CUF— William Little, Advanced GeoEnvironmemal, Inc., 837 Shaw Rd., Stockton, CA 95215