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JUL-31-98 FRI 06 06 AM DMG:RRNGO FIELD OFFICE FAX N0. 9747+5104 P, 04 -'1 (Page 3) ~~ MINE ID # OR PROSPECTING ID # M-77-215 ~ INSPECTION DATE 6-1-98 INSPECTOR'S INITIALS ate. $_ the best contact surface possible for the second section to adhere to. The cement pumping pipes and grout injection pipes were in place similar to the layout described in the 4-8-98 inspection report for the first section of the plug. The stainless steel drainaa.; and tracer injection pipes were lengthened using stainless steel unions. Some water seepage was observed coming from the foot of the rib whez'e it intersects the first plug section. Tk1e seepage flow was almost imperceptible. The ribs and back adjacent to the plug were not wet. The origin o£ the seep is unclear, but may indicate a leak past the first section of the plug. Trie alit, from the portal to the plug, is now fairly dry with only an occasional drip from the back. Homestake personnel indicated that discharge from behind the plug has decreased significantly in the last few days. Some of the flow is directed to the infiltration trench while the majority is directed to the evaporation sprinkler system. Homestake personnel were changing the location of the evaporation sprinklers when the inspector arrived ae tha site. When walking the area where the sprinklers had been operating, it was noted that a couple of small rills had formed and tetminated at Windy Gulch. This is the second time that the Division has had to caution Homestake about directing too much flow to the evaporation system, resulting in probable discharges co windy Gulch. Measures must be taken to ensure chat this condition does not occur again. Upon closure of the odic seal valve, the Division will not be inclined to allow future evaporative control of any mine discharge, temporary or otherwise, should it become necessazy. Wi:1dy Gulch was walked from approximately the 9100 foot elevation, up to the 93G0 bench. Flow from upper Windy Gulch is channele3 through the waste zock dump bypass culvert. There is no flow over the emergency spillway. No trash rack was in place at the culvert inlet. The inlet was clear of debris. Two springs xere observed at the toe of the 9360 waste rock dump. The upper spring is located approximately two-thirds of the way down from L-iie culvert inlet. this spring was flowing an estimated .5 - 2 g.p.m. This spring emerges from the waste rock dump at a point above the bottom of the Windy Gulch channel. Therefore, it appears chat this flow is not f z'om Windy Gulch, but may be a point discharge from the 9360 waste rock dump, Flow from a second spring emerged approximately 10 yards below the outlet o£ the bypass culvert. Windy Gulch has two flow paths at this paint, TYte flow from the culvert was in the east channel where flows were swift and the rocks lining the channel were clean. The spring is located in the west channel, adjacent to the toe of the 9360 waste rock dump. Flows from this spring were estimated at 20.30 g.p.m.. The rocks in ttie channel were ringed with white staining at the contact with the water surface. The sub-surface portions of the rocks were coated with an apparent algal growth. Conditions at [he site will bo reported to [he Colorado Department of Public Health and environment, Water Quality Control Division. 7 ~~„~Qnr_a ce Addre~ NAME _Alan Cbx OPERATOR Homestake M;nino Comn env STREET _650 California S[ree t_ CITY/STATE/ZIP _San Francisrn. CA 9910$_ cc: Tom Gillis, DMG ^ CE ^ BI, ^ b'S ^ H'R ^ HMWMD (CH) ^ SE wQcD (CH) - Sazah Johnson GTHER