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. Navarra Site:Potable Wate3`upply Well Program Page 5 of 7 monitoring program. There is no hydrogeologic or geochemical data that has been gathered at the Navarra Site that would suggest that there is any risk that groundwater extracted from this well might be affected by components of fuel hydrocarbons released at the Navarra Site. Wells to be Included in Revised Monitoring Program Based on the recommended elimination of selected wells from the program, the revised potable water-quality monitoring program would include the following three wells: Well ID Location CasaM 7500 West Eleventh Street BCNC 23950 Chrisman Road Suburban 23901 Chrisman Road Monitoring Frequency The recently-completed potable water supply monitoring program provided for a quarterly sampling frequency. However, as noted above, the total absence of any detectable concentrations of any analytes of concern in any of the samples recovered from any of the six wells over the completed one-year monitoring period demonstrates that the risk of future contamination of those potable water supplies is very low. As was succinctly stated at the March 30, 2005 seminar on Long Term Monitoring Optimization (LTMO) for Groundwater that was arranged for regulatory agency personnel that was hosted by the California Environmental Protection Agency (CaIEPA) in Sacramento and presented by the United States Environmental Protection Agency (USEPA) Office of Superfund Remediation and Technology Innovation (Ellen Rubin PhD, P.E., seminar leader), there is no scientific basis for quarterly groundwater-quality monitoring schedules except at the initial stages of site investigation to provided an understanding of seasonal variations in groundwater quality at sites on the East Coast of the United States, where the climate produces a quarterly Spring, Summer, Fall, Winter climatic cycle. In climates such as prevail in the greater part of California, or where variations in groundwater elevations and/or flow directions are dominantly affected by agricultural irrigation, monitoring should be scheduled according to the site-specific changes in hydrogeologic condition that actually prevail. Consistent with our full agreement with the recommendations made by the USEPA personnel at that seminar (which our staff attended), SJC recommends that the revised monitoring program should call for sampling and analysis of the potable water wells in February and September of each year, which months coincide with the typical low and high water table elevations at the site. As demonstrated by data and discussion included