2001-01-29_INSPECTION - M1977493

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MINE ID # OR PROSPECTING ID #: M- 1977 -493 PAGE: 10 INSPECTION DATE: 9 -26 -00 INSPECTOR'S INITIALS: ACS this area is poor to nonexistent as a result. DMG will require that plant growth medium be spread in this area and that the area be reseeded; this task to be accomplished prior to the end of the 2001 construction season. This small scale corrective action requirement need not affect the DMG decision on the request for surety reduction for the 3 -Dam project. Completion of this project is a major step in the reclamation of the Climax Mine. Upon receipt of adequate documentation of 3- Dam cover material thickness DMG will release the bond held for sloping and capping of 3 -Dam and for grading and topsoiling of the borrow pits. The Mayflower Tailing Pond flats were inspected. The beach area of the Mayflower impoundment (124 acres) was capped in a project that was completed in 1990. The capping material was borrowed from a pit to the east of the impoundment, which is the right bank of the former Ten Mile Creek valley though this reach. The free water pool of the Mayflower impoundment covers approximately 222 acres and is used as the primary water treatment pond for the Climax Mine. Climax Process water is treated by the addition of slaked lime and is routed via the tailing delivery pipeline to both Ten Mile and Mayflower ponds. Alkaline precipitation of dissolved metals occurs in the tailing ponds and the sludge settles out in the base of the ponds. Treated water is dosed with acid below 5 -Dam to meet pH requirements at the discharge point in Ten Mile Creek. A number of test borings were attempted on the capped area of Mayflower Pond. The two borings that penetrated into the tailing displayed capping material thicknesses of 16 and 19 inches. Based on these measurements, observation of the rock cap as a whole, review of the permit requirements as for reclamation of Mayflower pond, and discussions with Climax held in the field, the following clarification is provided to eliminate potential confusion in section 3.4 of the SR -03 application. Reading of section 3.4 could leave the impression that an 18 inch cap of borrowed rock capping material was applied to the Mayflower tailing surface followed by the application of an additional 18 inches of plant growth medium, for a total of 36 inches. Section 3.4 describes the plant growth medium as a clean sandy loam with an average of 2.8 percent organic content. It appears that the thickness of the capping material on the Mayflower Pond flats averages in the range of 18 inches total and that an effort was made to place the best available borrow material for plant growth at the surface of the fill. Even with this effort, the capping material is very rocky, exhibits some sulfide mineralization, and contains chunks of asphalt. The actual topsoil from the Mayflower borrow pit is reported to have been placed in the Mayflower topsoil stockpile. Subsoil and rocky borrow material from the pit was used to cap the tailing surface and outslope of 5 -Dam, and direct seeding was applied to the regraded borrow area as will be further discussed below. Given the permit requirement to apply a 1 foot to 3 foot variable cover to tailing pond flats, the DMG determines that the capping requirement has been fulfilled for 124 acres of the Mayflower impoundment as outlined in the SR -03 application. Revegetation of this acreage is not a component of the SR -03 surety reduction request, but based on observations made during this and previous inspections (see report dated 8/30/99) revegetation of the Mayflower impoundment shows great potential. In particular, the areas where biosolids have been applied, approximately 33 acres, have established a diverse stand of essentially weed free grass and forbs. An effort was made during and following the inspection to determine the status of the borrow area on the right bank of the Mayflower impoundment as it relates to the SR -03