SITE INFORMATION AND CORRESPONDENCE

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Mr. James Taylor -2 - 30 December 2009 Project Description: This project adds a second recirculation system that will be operated concurrently with the first. The extraction well for the second system is located about 90 feet side-gradient of the first extraction well and the injection point is into an iron formation about 90 feet upgradient of the first injection point. The second recirculation system was installed and tested in 2008, but has not been operated continuously. Each recirculation system will operate at about 6 gpm. If the iron reactivity diminishes such that an average 70% reduction in carbon tetrachloride relative to 2006 levels is not achieved after one year of operating the dual recirculation system, a contingency plan will be implemented. The contingency plan includes adding a carbon substrate to the reinjected water in order to augment the chemical reductive capability of the iron with reductive biological reductions. Continental Grain Company will submit a work plan, Notice of Intent, and a chemical analysis of the carbon substrate. Central Valley Water Board staff will determine if a new or revised Notice of Applicability is appropriate. Public Notification: On 23 July 2009, Continental Grain circulated a fact sheet notifying interested parties of its proposal to expand the treatment system. No comments were received during or after the 30- day comment period. Conditions of Approval: 1. Pressure transducers installed in monitoring wells MW-5B, MW-313 and MW-10B shall continue to provide groundwater elevation data monthly for the first year of operation. 2. If the groundwater elevation data shows that the injected water is causing a groundwater mound that extends to MW-513 and persists for more than 48 hours, then the injection rate shall be decreased by 2 gpm within 48 hours and Central Valley Water Board staff shall be notified. 3. The extraction rate shall not exceed 10 gpm at any extraction well. 4. If the average concentration of carbon tetrachloride in monitoring wells MW-413, MW- 9B, MW-10B, and MW-13B does not decline to at least 70% of the 2006 average level in these wells, the Discharger shall implement the contingency plan, including providing an implementation-specific work plan, a chemical analysis of the carbon substrate, and a Notice of Intent. 5. The project will be operated in accordance with the requirements contained in the General Order and in accordance with the information submitted in the Notice of Intent. 6. The required annual fee (as specified in the annual billing you will receive from the State Water Resources Control Board) shall be submitted until this Notice of Applicability is officially revoked. 7. Failure to abide by the conditions of the General Order could result in an enforcement action as authorized by provisions of the California Water Code.