INSPEC46334 - Laserfiche WebLink

Home Browse Search

COMMENTS -COMPLIANCE ~~,.,~ SI/'n~P/~,r~Q (.~v-0~' ~~~/s a~~n~~oi ~~ Below are comments on the inspection. The comments include discussion of observations made during the inspection. Comments also describe any enforcement actions taken during the inspection and the facts or evidence supporting the enforcement action. Phase II Bond Release for the 720 Pit (cont.) Vegetative Cover (cont.) -The Operator did use the reclaimed area for grazing in the summer of 2000. They had 400 head of cattle grazing for two weeks. This is equivalent to a 50% utilization rate. They indicated that they would use the reclaimed area for grazing again this summer (2001) at about the same rate. An excellent stand of Big Sagebrush has been established, with seed heads were observed on several of the shrubs. Some of the other dominant species observed were Yarrow and Fringed Sagebrush. The weed control measures that have been undertaken the last couple of years have proven to be very successful. Some Canadian Thistle was observed but to a much lesser extent than in the past several years. The Operator should continue weed control as necessary. Topsoil Replacement -The permit requires that a minimum of six inches of topsoil be replaced on the reclaimed 720 Pit. The Operator did not provide any data on topsoil replacement in the Bond Release Application so the Division took several field measurements. A total of six holes were dug to measure the topsoil replacement depth. The depths ranged from seven inches to eleven inches with an average depth of 9.7 inches. The first two of these holes were about 500 feet West of Pond A with depths of 10 and 11.5 inches; the second two holes were about 1000 feet North (of the first two holes), both having depths of 11 inches; the third two holes were about 300 feet North of Ditch PD2 and 250 feet East of the edge of the highwall with depths of seven inches and 7.5 inches. The field measurements of the topsoil replacement depths confirmed that the topsoil was replaced in accordance with the permit requirements. Hydrologic Reclamation (Sedimentation) -The Operator used sedimentation modeling to further demonstrate Phase II Bond Release criteria (Rule 3.03.1(3)(b)) have been met using the Revised Universal Soil Loss Equation (RULSE). These calculations were confirmed by the Division. The calculated (estimated) sediment yield for the reclaimed 720 Pit was 0.54 Tons/Acre/Year. The calculated (estimated) premining sediment yield was 1.12 Tons/Acre/Year. This gives an estimated postmining sedimentation yield of 48% of the premining yield. The criterion for sedimentation for this area has been met. The inspection confirmed the calculations. There was no noticeable erosion on the reclaimed 720 Pit and both of the ditches (PD1 and PD2) did not appear to contain any sediment. Both ditches appeared to be stable and were well vegetated. There did not appear to be any sediment being deposited at the inlet of Pond A. There did appear to be a small low spot (where water was pooled) in Ditch PD1 about 500 feet before it converges with Ditch PD2. This did not appear to be significant and did not appear to be causing any problems. Phase II Bond Release for Pit 1 The Operator is requesting a 25% ($217,298.00) Phase II Bond Release for Pit 1. The total cost for reclamation of Pit 1 was $869,195.00.