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_' t- • (Page 2) MINE ID ~` OR PROSPECTING ID ~# M-77-493 INSPECTION DATE 9 15 94 INSPECTOR'S INITIALS ACS OBSERVATIONS A monitoring inspection of the Climax Mine site located in Lake, Summit and Eagle counties was conducted. All surface areas of the site were visited with the exception of the open pit and the Arkansas Lake locations. The Robinson tailing impoundment was inspected first. The free water pond on the Robinson impoundment tails has been drawn down with a submersible pump to facilitate placement of a rock cover over the tailing surface. Placement of the rock cover is an approved component of the reclamation plan. Approximately 200 acres of the Robinson tailings had been covered at the time of thin inspection. An estimated total of 350 acres will be covered as part of the current project. The capping material is being windrowed by dump trucks and is being spread in a single 18 inch lift by dozers. The free water pond will be surrounded by the rock cap, and will be utilized as a process water pond. As a result, the entire Robinson tailing surface will be covered with a rock cap, or will be submerged, which will significantly reduce the potential for duet generation. The operator ie obtaining permits for biosolide application to the Robinson impoundment rock cap in order to build soil for revegetation. Piezometera are being installed in No. 1 and No. 2 dame, which impound the Robinson tails. Piezometera are also being installed in No. 5 dam. Installation will be completed this fall. The Moly-Oxide pond AKA Eagle Park reservoir, and No. 4 Dam were inspected. Over the last year, the oxide tails have been reslurried and pumped to the Tenmile tailing pond in accordance with the terms of approved technical revision TR-005. To date, approximately 15 to 20 percent of the total 1 million cubic yards of oxide tails have been transported by the reslurry method. On July 4, 1994 a pump feed tank on the oxide tailing slurry line overflowed, with approximately 900 gallons of the slurry entering the Lower North Interceptor Canal which ultimately flows into the Eagle River. This incident was reported to the Water Quality Control Division and to the Division of Minerals and Geology (DMG) when it occurred. The steps taken to prevent a recurrence were described at the time of the reporting, and were judged by DMG to be adequate. The steps taken are: 1) A switch has been installed to automatically shutdown the slurry pumps when a feed tank high level is indicated, 2) The Lower North Interceptor Canal has been diverted into the Moly-Oxide pond by construction of an earth cofferdam within the canal. The cofferdam was inspected and found to be adequate to prevent releases to the Eagle River from the canal. Since the cofferdam will have to be removed to allow conveyance of spring runoff in the canal, the~Diviaion will specify that the Blurry transport of Oxide tails approved in TR-005 may only proceed when the cofferdam is in place and functioning. The operator indicated that most of the remaining 800,000 cubic yards of Oxide tails will likely be transported to the Tenmile pond by truck. No revision to the permit will be required for the change to truck transport, however a letter report must be submitted describing the operation and describing any environmental protection measures to be implemented. The No. 1 Dam face was inspected. Revegetation efforts on No. 1 Dam have been only very marginally successful with a few areas of fairly vigorous growth surrounded by large areas of little or no establishment. Prior to the second seeding, the operator should analyze the soil in both the successful and unsuccessful areas to determine if soil amendments for pH adjustment or fertilization are needed. Also, lack of available moisture on thin south facing elope could be the chief difficulty, and the operator's consideration of straw mulch application may be the best approach, if the straw can be held in place on the exposed slope. No. 3 dam was viewed and photographed from an overlook on the west aide of the valley. This dam face is scheduled to be rock capped during the 1995 construction season. The Mayflower Pond and No. 5 dam reclamation was observed. Rock capping and biosolids application in this area has resulted in a good stand of grass. Diversity and self- suatainability of this reclaimed area will have to be monitored and assessed over time. The next atop was at the "E" ore stockpile. The lower west slope of the "E" stockpile adjacent to Highway 91 is the borrow source for the capping material going to the Robinson tailing pond. The borrow area is being sloped to 4:1 and covered with a thin layer of topsoil. The topsoil utilized is from some small piles located near the work area that were not included in the topsoil inventory in the Reclamation Permit. As a result, none of the documented topsoil resource is being depleted for this reclamation effort.