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may have bridged across underlying rocks, but eventually collapsed. There were no signs of flowing water having formed the holes (e.g., channel scour on the ground surface or sediment deposition in the holes). Regrading and seeding the azea of the holes was discussed with the mine operator. This work would use rubber-tired equipment for minimizing re-disturbance of the reclamation. Collapse of Mine No. 3 Portal Closure - The backfill closure of Mine No. 3 has collapsed, creating a concave depression on the ground surface measuring approximately 30 feet long X 20 feet wide X 8 feet deep. No structures or voids were visible in the bottom of the depression. Stan Muhr explained that last fall when he found the depression, he used a backhoe to knock down the sides of the depression in order to reduce the hazard to livestock. He said that in the bottom of the depression he could see what appeazed to be concrete sidewalls of the portal, which may have bridged the backfill, resulting in the collapse. We discussed backfilling the depression so that material is not bridged to ensure long-term stability. Subsidence There were no signs of subsidence from underground workings around the portal azeas. Snow cover precluded inspecting subsidence beyond the portal areas. These areas will be inspected in an upcoming aerial inspection and site visit, probably in June. Attendees on April 17 were offered the opportunity to participate in the site visit. Fish and Wildlife Although no wildlife other than birds was seen during the inspection, evidence of wildlife use of the reclaimed azeas was evident in the form of droppings (deer or elk), hoof prints, and browsed shrubs. The mine site appeared suitable for wildlife habitat with North Thompson Creek's riparian zone bisecting the area, and mixed aspen/conifer cover on adjacent hillsides. Adrake/hen pair of Mallard ducks was on the Long Pond on the last day of the inspection. Reveeetation The mine site in and around the Water Development Area and on the Mine No. #3 portal bench has good vegetative cover that is dominated by 4-5 foot tall Rubber Rabbitbrush, with Crested wheatgrass and fescue as the dominant herbaceous species. Cicer milkvetch is an abundant forb. Crested wheatgrass and fescue cover the refuse pile. The amount of cover appears adequate to control erosion. No species toxic to livestock or wildlife were found. Weed problems were not evident. General Mine Plan Comaliance Upon completion of the inspection, the operator appeared to be in compliance with all aspects of the mine plan. DRMS is reseazching compliance issues regarding the dischazge of Mine No. 3 water outside the pond treatment system. The operator appeared to have fulfilled all reclamation obligations, with the exception of the sinkholes on the refuse pile and the collapsed Mine No. 3 portal (see preceding discussion of Slides and Damage). 7