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<br />Additional monitoring will be necessary over the next 3-6 months [o make any determination whether <br />[he sealing of these wells has had any effect on the methane concentrations in the soil. <br />OBSERVATIONS AND FINDINGS <br />Mining operations replace topsoil, when available, over reclaimed areas prior to re-seeding. In [he <br />case of the Golden Eagle mine, many of [he facility areas were disturbed prior [o August 1977 and <br />topsoil was not stripped and stockpiled for later use. Map 13-B of the approved permit depicts areas <br />where topsoil was re-distributed upon site reclamation. The Division verified topsoil replacement <br />depths in July 1997 in three areas; Pond 5, tipple area of facilities area, and [he development waste <br />pile. Topsoil was replaced as required by [he Golden Eagle reclamation plan and in accordance with <br />Rule 4.06.4. Revegetation success can also be an indication of adequate soil replacement. <br />The applicant submitted detailed vegetation sampling data as part of the bond release application. <br />This data was collected in June 2000 using approved and accepted methodologies. The approved plan <br />calls for comparison to reference areas to determine revegetation success. Herbaceous production <br />was measured on reclaimed pastureland (areas A and R on Figure A-] of the application) and <br />compared to [he AVF reference area east of area R. Vegetative cover and species diversity were <br />evaluated on the reclaimed rangeland (areas B - Q on Figure A-1) and compared to the Rangeland <br />reference area located west of area H. <br />The measured production on the reclaimed pastureland was measured at 95.2% of the value measured <br />on the AVF reference area. This exceeds the requirement of Rule 3.03.1(2)(b) and 3.03.1(3)(b). The <br />mean absolute cover on the reclaimed rangeland exceeds the mean absolute cover measured on the <br />rangeland reference area by 3.6% (24.8% vs. 21.2% respectively). <br />Field inspection indicates no evidence of on-going erosion. Terrain in the steepest portions of [he <br />reclaimed lands shows no evidence of significant erosion. Surface water runoff is routed efficiently <br />through and around the reclaimed areas. The mine continues [o conduct surface and ground water <br />monitoring in accordance with the approved hydrologic monitoring program. No surface or sub- <br />surface water pollution due [o mining at this site has been identified through review of pas[ or present <br />monitoring data. Mine flooding is anticipated, but at this time has not reached a level that can be <br />measured by one of three water monitoring points, GEM-l, GEM-2, and GEM-3. GEM-1 is the <br />Intake Shaft location labeled Sotrth /make on Map 18 and GEM-2 is the site labeled 3N /make. No <br />gravity drainage from the portal or any other mine borehole or sealed opening is anticipated. <br />The area of methane in the soil profile is located east of the permit boundary on private land owned in <br />part by Mr. John Toupal. Methane concentrations in the soil in this area are sufficient to replace <br />oxygen and cause vegetation die-out over an area approximately 5 acres, more or less. This problem <br />was first inspected by the Division as a result of a citizen complaint in September of 1996. BRI is <br />investigating the extent of the contamination as well as possible sources for the methane in the soil. <br />Two gas wells in the area were recently cemented and abandoned. The COGCC does not believe [he <br />gas wells are the source of the methane. <br />Based upon data collected to-date, there is sufficient evidence to determine conclusively that the cause <br />of the vegetation die-out is due to the lack of oxygen in the soil profile, leading to suffocation of plan[ <br />