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10 <br />within the permit to promptly repair any depressions, swells, or cracks if any were to develop on the <br />alluvial valley floor, as a result of subsidence. Subsidence monitoring conducted by the operator between <br />1982 and 1989 dztected a maximum of 0.3 feet of residual vertical subsidence. No disruption of <br />irrigation structures or other possible surface effects of subsidence interfering with farming on the alluvial <br />valley floor have been observed by the Division, or brought to the attention of the Division or the <br />operator by landowners or the public. <br />Based on review of subsidence and hydrologic monitoring records, and hydrologic impact evaluation <br />conducted in association with the bond release process, the Division has determined that the Red Canyon <br />Mine has been operated and reclaimed so as to preserve the essential hydrologic functions of alluvial <br />valley floors within and adjacent to the permit area. <br />Protection of the Hydrologic Balance <br />During the bond release review, the Division noted rising water levels in coal seam monitoring well E-1, <br />and questioned whether this could be indicative of rising water levels in the abandoned workings. If this <br />were the case, the concern was that there would likely be discharge from the sealed portals in the future. <br />These issues were satisfactorily resolved, allowing the Division to conclude that rising water levels in <br />monitoring well E-l, were not indicative of rising water levels in the abandoned workings, and that <br />permit projections which indicate that the sealed portals will not discharge water to the surface are valid. <br />Increasing water level in well E-1 appears to be due to recharge from the surficial glaciaUalluvial aquifer, <br />rather than due to inflow from the abandoned mine workings, because the quality of water in the well is <br />not degraded, as would be expected if there was inflow from abandoned workings. Water quality data <br />for Ward Creek, within the permit area, have shown effects of mining to have been less severe than worst <br />case permit projections, and well below the Division's suspect levels for material damage. Additional <br />detail regarding the hydrologic evaluation is included in the Division's letter of May 27, 1999, and an <br />inter-office memorandum enclosed with that letter. No apparent impacts to surface or groundwater <br />resources were observed during the bond release inspection. <br />Based on review of monitoring records and annual hydrologic reports, and additional information <br />provided by the operator during the bond release evaluation, the Division finds that the Red Canyon Ivline <br />has been operated and reclaimed so as to protect the hydrologic balance in the permit and adjacent areas. <br />Reclamation of monitoring wells <br />Reclamation of all monitoring wells in the permit area, with certain exceptions, was conducted in June <br />and July, 1998, and is documented in a piezometer abandonment report dated July 27, 1998, submitted <br />to the Division on August l2, 1998. The only wells not reclaimed prior to the bond release inspection <br />were four wells requested by the Division to be left open to allow for additional sampling prior to bond <br />release if necessary, and one well which was apparently damaged by road construction that could not be <br />located. <br />