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<br /> <br />Mr. James Cowart <br />December 17, 1997 <br />Page 4 <br />proposes to remove the liner beneath the tailings, bulldoze <br />the berm into the pond, and fill the remainder of the <br />depression with useable waste rock material within the permit <br />area and/or clean fill from off site. This would be followed <br />by a 12 inch layer of plant growth material. The DMG is not <br />clear if the 'berm' to be bulldozed refers to the two foot <br />high temporary berm placed on the dam crest in 1995, the pond <br />dam, or both. Please clarify. <br />The staff believes that reclamation will be most successful <br />under the currently approved plan. This includes leaving the <br />liner in place, maintaining the tailings dam embankment, <br />covering the tailings with geotextile, placing well graded <br />rock and topsoil. Any variation such as removing, cutting, or <br />folding the liner, regrading the dam embankment, deleting the <br />geotextile layer or reducing the thickness of the rock cover <br />would first need to be considered and approved in a revision <br />to the permit. You should be aware that a portion of the <br />reclamation plan may have already been completed. In a letter <br />dated July 18, 1995, the operator committed to implementing <br />the approved reclamation plan on the downstream face of the <br />tailings dam after the embankment construction was completed. <br />This was an erosion prevention measure and as such, should <br />have already been completed. <br />Please describe how the tailings will be mixed with the liming <br />agent and the measures employed to ensure that the liner will <br />not be damaged during application. At what pH or acid-base <br />potential will the treated tailings be considered neutralized? <br />Past analytical data has shown that flyash can contain <br />hazardous constituents. Before using flyash to treat the <br />tailings, you will need to demonstrate with analytical data <br />that it is non-hazardous. Please state the operator's <br />commitment to do so and submit a plan to accomplish this. <br />The conceptual plan discusses filling the pond depression with <br />fill material from useable waste rock piles within the permit <br />area and clean fill from offsite as necessary. Please refer <br />to section 6 of DMG representative Allen Sorenson's letter <br />dated May 19, 1997 requiring chemical and physical <br />characterization of on-site waste rock. The operator is <br />reminded that the criteria established in Mr. Sorenson's <br />