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(Page 21 • MINE ID Jl OR PROSPECTING ID aY M-82090 INSPECTION DATE 7-12-99 INSPECTOR'S INITIALS SSS OBSERVATIONS This was a partial inspection of the Camp Bird Mine, conducted to evaluate the reclamation activities completed to date in anticipation of a financial warranty reduction request. The reclamation was conducted to reduce the reclamation liability prior to July 9, 1999, the date that an increased bond amount was due. Prior to July 9, the operator submitted documentation indicating that the reclamation liability had been reduced to a level where the current 5100,000.00 bond was adequate to guarantee reclamation of the site. This inspection verified that documentation. ZMK Construction, Inc. had completed n=grading of the east and west tailings ponds, placement of a 4 to 6 inch layer of colluvium over the regraded tailing surfaces, and installation of drainage and erosion control structures. The east tailing pond was 90 percent regraded, with the east end requiring regrading when all colluvium is removed. The operator indicated that some areas of both tailing impoundments were soft. It is anticipated that the addition of the colluvium and establishment of vegetation will reduce the amount of moisture that infiltrates the tailings, thereby stabilizing these soft areas. The east tailing impoundment surface is now sloped at approximately a 6H:7 V grade and is covered with an average of 6 inches of colluvial material. There are some spots on the east tailing impoundment where a small amount of tailings mixed with the colluvium. These areas are minimal and occurred where the dozer had trouble moving around without getting stuck. A change to the current west tailing pond regrading plan was implemented resulting in pond surfaces draining away from the outslopes and to the east instead of the west. This plan required less tailing material to be moved, which was desirable, given the tough grading conditions where the tailings were soft. A 120 foot length of 18 inch diameter HDPE pipe was installed to carry drainage flows off the east end of the west tailing pond. The inlet is fitted with an HDPE apron with a rock armored drop slope leading to it. The operator was instructed to install sediment control around this inlet to minimize sediment discharge until vegetation is established. The surface of the regraded tailings was covered with an average of 6 inches of colluvial material. Very little mixing of tailings and colluvium was noted on this impoundment. The outslopes of this impoundment were not affected by the regrading. It is believed that the stability of these slopes would be adversely affected by any attempts to reduce their grade. However, the operator is considering options for establishing vegetation on these slopes to increase :stability against erosion. The portal closure and rehabilitation project was complete with a bat accessible locking gate installed. The drainage from the mine had been re-established in ttie side ditch. Collapsed timbers and earth were removed. The operator was instructed to add additional strapping and rebar to prevent access through gaps around the gate and to discourage opening of the gate by pulling with a chain or winch. The snowshed structure is 75 percent removed with the portal area being the last part to remove. The operator indicated this would be complete in the next two weeks. The machine and carpenter shops were completely removed except for the concrete pads and machine shop stem walls. The core storage building is approximately 50 percent dismantled and the scalehouse is completely dismantled with only the footers remaining. The oil storage pad timbers were being removed during this inspection and were 75 pera~nt removed. The oil storage elevated concrete pad still requires removal. All pads and footers that are on grade can be lelt in place if the operator covers them with adequate cover to allow for successful vegetation establishment. Release of financial warranty held for completion of the tailing impoundment regrading, drainage establishment, and cover with colluvium is recommended for approval. Release of warranty held for portal closure, and for scale house, machine shop and storage building demolition is recommended for approval. Also, release of appropriate percentages of warranty held for tasks partially complete, as described above, is recommended for approval. A few patches of Canada thistle were noted on site. The operator indicated that he would canvas the entire site and begin a noxious weed spraying program within the next few weeks. The most notable patches of thistle were located on the outslope of the east tailing impoundment seep dam and colluvium stockpile. With this patch being on the base of the colluvium stockpile, the operator is cautioned to closely watch the areas of colluvium replacement. Any thistle establishment on these areas should be treated with herbicide as soon as they are recognized.