SITE INFORMATION AND CORRESPONDENCE

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The Source Group dated May 31, 2006). The sampling and gauging should occur over several events spaced regularly over a period that extends into early fail when the deeper water supply well on the RFS site has historically demonstrated a significant seasonal nitrate impact to the deeper water- bearing zone. The sampling techniques should be the same for all the monitoring wells. 2. Other constituents associated with RFS operations that are in addition to nitrate and potentially contained in any spills that occur at the site should also be included in the sample analysis. The selection of these other constituents should be based on a review of the materials handled, both currently and historically, at the RFS site. The additional chemical analysis results may provide "fingerprint" information that may resolve the question as to whether RFS operations have impacted groundwater surrounding the site. If no other constituents are identified as good candidates for analysis, nitrogen/oxygen isotope analysis should be considered as a possible fingerprinting tool. 3. Additional nested (shallow and deeper) monitoring wells should be installed between the RFS site and City Well 12. Two wells might be installed on: a) the land within the interchange between Route 99 and Jack Tone Road, and b) the Southern Pacific Transportation Company corridor. 4. The top-of-casing elevations for the RFS monitoring wells, especially the newest well RMW-IS-R, should be verified so that the direction of groundwater flow can be determined with a reasonably level of certainty. Additionally, the City would like to note an issue regarding the data RFS presented to you during the meeting last week. As you may recall, the data provided by RFS consisted of averaged concentration data. While an average may be useful for certain purposes, it is essential that raw data be evaluated for purposes of site-specific evaluation, not averages. This is because the raw data shows trends and cycles, (i.e. those observed in the RFS water supply well) while averaging data obscures the analysis. The City is encouraged by the fact that during last week's meeting, the RWQCB discussed its continued desire to identify the amount of contamination that is being contributed by RFS' operations. Additional measures must be undertaken to quantify the extent of the contamination caused by RFS. In formulating future directives for RFS, the City respectfully requests that the RWQCB consider the comments stated in this letter, in my letter dated December 12, 2006, and in the report by The Source Group, dated May 31, 2006, and titled Evaluation of Potential Nitrate Sources near City of Ripon Well #12. As you may recall, The Source Group's report offered evidence that contradicted RFS' conclusion that there is a major alternate source of the contamination. Should you need copies of any of the foregoing