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Memo to Wally Erickson 2 April 15, 2008 <br />Amendment AM-03 Water Issues Permit No. M-1988-112 <br />Applicant must provide a demonstration that any leakage through the geomembrane will not escape the capture <br />zone of the west pit dewatering wells. <br />The Applicant has provided information in the Application relative to the fate and transport of Fluoride and <br />Manganese in west pit water applied to the Salazar Ranch irrigated lands. Total Dissolved Solids (TDS) in the <br />west pit water also exceeds the applicable ground water standard. Therefore, the Applicant must provide an <br />evaluation of the fate and transport of high TDS water. <br />In accordance with Rule 3.1.7(6)(b)(ii), points of compliance for ground water must be established at the west <br />edges of both irrigated fields at the principle axis of ground water flow. Because the points of compliance will <br />be immediately adjacent to the irrigated lands there is little space available to provide early warning that <br />fluoride, manganese, or TDS levels in the affected ground water might be approaching the limits allowed in <br />ground water standards. Therefore, the DRMS will require that the irrigation of crops using west pit water be <br />implemented in a stepwise manner with the contingency to return to the existing system of west pit water <br />management if it is observed that compliance with ground water standards cannot be achieved. The stepwise <br />procedure must include: <br />1. High frequency of sampling and analysis of ground water during irrigation, initially weekly and to <br />continue until otherwise approved by the DRMS. <br />2. Calibration of the ground water model contained in Appendix F midway through and at the end of each <br />irrigation season until a lesser calibration frequency is approved by the DBMS. <br />3. Sufficient bond to drill capture wells and construct any other infrastructure necessary to remove <br />potentially contaminated ground water down gradient of the irrigated lands, return and treat the captured <br />ground water at the treatment plant. <br />Because of the close proximity of the points of compliance to the irrigation activity, and because the model <br />included in Appendix F predicts that fluoride levels in the ground water below the irrigated lands will increase to <br />with 0.58 mg/L of the applicable standard, the ground water compliance plan previously approved in this permit <br />and.proposed for the Salazar Ranch in this amendment is not appropriate. Actions to immediately respond to <br />information that ground water standards have been or will be exceeded must be described by the Applicant. <br />Clearly, immediate cessation of irrigation using west pit water would be the first response action. The Applicant <br />must provide a proposal to implement the stepwise procedure for DRMS review, including: <br />1. A proposal for locations, construction, development, and monitoring additional wells, including <br />provisions to control and assure the quality of the data generated. <br />2. Response and contingency plans, and an estimate of their cost. <br />It is critical that no west pit water be allowed to runoff the irrigated lands and enter waters of the State. The <br />Applicant must provide a plan that will assure runoff does not occur. <br />cc: David Bird, DRMS (via email) <br />Tony Waldron, DRMS (via email) <br />Carl Mount, DRMS (via email) <br />c:\acs files\btl mm am3\Water Management and Water Quality Issues.doc <br />