Laserfiche WebLink
• (Page 3) • <br />MINE ID # OR PROSPECTING ID # M-77-215 <br />INSPECTION DATE 6-1-98 INSPECTOR'S INITIALS SSS <br />the best contact surface possible for the second section to adhere to. The cement pumping <br />pipes and grout injection pipes were in place similar to the layout described in the 4-8-98 <br />inspection report for the first section of the plug. The stainless steel drainage and tracer <br />injection pipes were lengthened using stainless steel unions. <br />Some water seepage was observed coming from the foot of the rib where it intersects the first <br />plug section. The seepage flow was almost imperceptible. The ribs and back adjacent to the <br />plug were not wet. The origin of the seep is unclear, but may indicate a leak past the first <br />section of the plug. <br />The adit, from the portal to the plug, is now fairly dry with only an occasional drip from <br />the back. Homestake personnel indicated that discharge from behind the plug has decreased <br />significantly in the last few days. Some of the flow is directed to the infiltration trench <br />while the majority is directed to the evaporation sprinkler system. <br />Homestake personnel were changing the location of the evaporation sprinklers when the <br />inspector arrived at the site. When walking the area where the sprinklers had been <br />operating, it was noted that a couple of small rills had formed and terminated at Windy <br />Gulch. This is the second time that the Division has had to caution Homestake about <br />directing too much flow to the evaporation system, resulting in probable discharges to Windy <br />Gulch. Measures must be taken to ensure that this condition does not occur again. Upon <br />closure of the adit seal valve, the Division will not be inclined to allow future evaporative <br />control of any mine discharge, temporary or otherwise, should it become necessary. <br />Windy Gulch was walked from approximately the 9100 foot elevation, up to the 9360 bench. <br />Flow from upper Windy Gulch is channeled through the waste rock dump bypass culvert. There <br />is no flow over the emergency spillway. No trash rack was in place at the culvert inlet. <br />The inlet was clear of debris. <br />Two springs were observed at the toe of the 9360 waste rock dump. The upper spring is <br />located approximately two-thirds of the way down from the culvert inlet. This spring was <br />flowing an estimated .5 - 2 g.p.m, This spring emerges from the waste rock dump at a point <br />above the bottom of the Windy Gulch channel, Therefore, it appears that this flow is not <br />from Windy Gulch, but may be a point discharge from the 9360 waste rock dump. Flow from a <br />second spring emerged approximately 10 yards below the outlet of the bypass culvert. Windy <br />Gulch has two flow paths at this point. The flow from the culvert was in the east channel <br />where flows were swift and the rocks lining the channel were clean. The spring is located <br />in the west channel, adjacent to the toe of the 9360 waste rock dump. Flows from this spring <br />were estimated at 20-30 g.p.m.. The rocks in the channel were ringed with white staining at <br />the contact with the water surface. The sub-surface portions of the rocks were coated with <br />an apparent algal growth. <br />Conditions at the site will be reported to the Colorado Department of Public Health and <br />Environment, Water Quality Control Division. <br />T ~ E Contact Address cc: Tom Gillis, DMG <br />^ CE <br />NAME Alan Cox ^ BL <br />OPERATOR Homestake Mining Comnanv ^ FS <br />STREET 6 0 a~+fo n+a ¢ ^ HW <br />CITY/STATE/ZIP San Francisco. CA 94108 ^ HMWMD (CH) <br />^ SE <br />WQCD (CH) - Sarah Johnson <br />^ OTHER <br />