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. .' J INSPECTION REPORT - PAGE 2 FILE N0. 77-215 DATE: August 2, 1985 OBSERVATIONS OF IMPORTANCE: 1. The inspectors were accompanied by Mr. Jerry Danni and Mr. Richard Bolling during this inspection. There was no active mining at this site during this inspection. 2. Prior to the field inspection, Mr. Bolling gave a presentation on the construction activities related to the cut-off trench in the tailings dam. This dam has been evaluated for stability (D'Appolnia report May 1983). A soil-bentonite slurry wall cut-off trench was installed during the 1983 construction season to control seepage. The methodology and approach implemented by Homestake to resolve problems concerning the structure are to be commended. 3. This is a flotation mill process which includes Pachuca tank cyanide leaching of mill tailings slime. The tank area was inspected and has adequate spill prevention control; a 3.5 foot concrete wall is constructed around the tanks to contain any possible spills. Possible leaks from the piping and p]umbing of the system are either within the mill building. Solutions from exterior plumbing would be contained by the spill preventia concrete berm. 4. Chemical barrel storage in the mill area is well contained. Cyanide barrels are stored within the building. Activated carbon drums are stored outside adjacent to the Pachuca tank area. The inspectors noted some chemical barrels are poorly stored on the west side of the mill building. In addition, numerous empty chemical and oil barrels were observed at the crest of the waste rock dump. See recommendations no. 1 and no. 2. 5. The Windy Gulch waste rock dump area was inspected. Some minor trash has been mixed in this dump and is visible on the outslope face. Presently, mine refuse is being disposed in a small pit on the top of the waste rock dump (north of mill building). This plan is adequate but is not addressed in the permit. It was discussed that trash disposal at mines is of concern and that mine refuse should be disposed using good engineering judgment. See recommendation no. 2. 6. A technical revision was submitted and approved to construct a culvert diversion near the toe of the dump to control drainage. This has not been fully constructed due to the lack of further wasterock disposal. 7. The Bulldog Mine portal area was inspected both the millsite and minesite have upland drainage control. 8. Discharge for the portal is approximately 300 qpm and is treated at the Windy Gulch water treatment plant. Sludge from the treatment plant is pumped to the tailings pond. The treated water is discharged into the Windy Gulch waste rock pile drainage control culvert. (Continued on page 3)