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Report: Grouiidwater-guality Monitoring—Jarzua+y 20,2003: 7500 West Eleventh Street, Tracy, CA. Page 15 -- did in our report on the October 25, 2002 round of groundwater-quality monitoring (The San Joaquin Company Inc. 2002a), we again strongly recommend that Monitoring Wells MW-3A, MW-3B and MW-12A be closed at the earliest possible date to eliminate the unnecessary risk to the quality of groundwater in the deeper aquifers beneath the site. f ! 3.2 Close Redundant Well MW-8 We also repeat our recommendation that Monitoring Well MW-8 be closed. That well =-A. has served its site characterization function and further groundwater sampling from it serves no current useful purpose. Continued monitoring of groundwater in that well unriecessarily adds expense, which has to be funded by the California Underground Storage Tank Cleanup Fund (USTCF), to the cost of the environmental management program for the site. . 3.3 Reduce Monitoring Frequency to Twice per Year Because no significant new information regarding the characteristics, distribution and movement of fuel hydrocarbons beneath the site are being generated from the quarterly rounds of groundwater-quality monitoring being conducted at the site, SJC repeats its recorn.mendation that to match the local cycle of rising and falling groundwater in the shallow aquifers beneath the site, which cycle is controlled by regional agricultural irrigation practices, future rounds of groundwater sampling and analysis be conducted only twice per year, in late February and late September. 3.4 Rcrnediate Area of Floating Product Across West Eleventh Street An issue of primary environmental concern at the 7500 West Eleventh Street site continues to be the high concentration of fuel hydrocarbons and floating product in groundwater on the north side of West Eleventh Street, directly down-gradient from the subject property. SJC again recommends, as was originally proposed in the report on the extended site characterization program that was completed in April 2002, that a program to remove floating product from the water table in the area around Monitoring Well MW- 7 be implemented as soon as it is practicably possible, and, while doing so, to excavate and dispose of soil containing high concentrations of fuel hydrocarbons that is also ,i located there (The San Joaquin Company Inc. 2002c). :I :a The remediation methods to be applied in the area of Monitoring Well MW-7 would be essentially the same as those that were employed in 1999 to remove floating product and i . remediate contaminated soil on the 7500 West Eleventh Street property itself, the efficacy of which have been clearly demonstrated by on-going monitoring of water quality in Monitoring Wells MW-3 and MW-4. 3.4.1 Recommended Remediation Process The following is a brief description of the proposed remediation process taken from the original proposal made by SJC (The San Joaquin Company Inc. 2002c). J sic