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Recoverv/Production Wells-All active recovery wells (3A-SV, 3A-4H, lA-SHR, 4A-6V) <br />are completed with cement to surface. Shut-in recovery wells (91-1 V and 93-3) are <br />scheduled for P&A in 2004 or 2005 per permit requirements. NSI is proposing other <br />action for three shut-in wells: <br />88-1 was approved as a subsidence monitoring well in 1994 with radioactive bullets <br />installed to monitor ground movement. Well casing is cemented to surface. NSI <br />proposes to leave 88-1 as a monitoring well. <br />4-2V was never connected to a cavity, and casing is cemented to surface. This well will <br />require future horizontal drill hole connection for production. This well was never "shut- <br />in" as it has never been connected to a cavity and presents no possible risks. NSI <br />requests approval to remove this well from shut-in status, as it is neither shut-in nor <br />active. <br />2A-2V will be plugged to the A-Groove and re-completed as second raw water well <br />within 18-months, if planned activity is approved by the regulator agencies. <br />Monitoringwells- Monitoring wells (EX-3, 90-2, II2I-7, DS-2, 89-1, 90-3, IRI-6, BG-1, <br />89-2, 90-4, IRI-4, 89-3, IRI-1, IIti-5, IItI-8, DS-3, BG-4, 93-2M, 4A-1V, 4A-SM, 94-1M, <br />90-1) meet the minimum requirements for isolation of aquifers and preventing movement <br />of contaminated mine water into USDW aquifers. The only exception is 94-1M, which <br />has cement to isolate the A and B-Grooves and Dissolution Surface, but may not have <br />cement between the Perched and A-Groove Aquifers. No acfion is planned as the <br />Perched has minimal quantities of water at this location and Perched aquifer water quality <br />is of higher quality than the A-Groove. No evidence from Perched monitoring wells <br />indicates significant de-watering effects. Subsidence well 3M-TDR not included in <br />Tables 2 and 3 needs to be cemented to prevent water movement downward into the <br />Dissolution Surface Aquifer and cavities. Plugging of 3M-TDR is currently in progress. <br />NSI believes this letter addresses all the requirements for pazagraph #I, Pazt II (B). If <br />there are any questions, please contact Mr. Rod Storey, drilling engineer or myself. <br />Sincerely, G~ <br />~~"~ <br />Ed Baker, REM <br />EHS Manager <br />Cc: BLM <br />,i~Iv1G <br />