PERMFILE129522 - Laserfiche WebLink

Home Browse Search

topsoil. This leaves roughly 113,000 cubic yards of topsoil to be sold or used as fill. It is the division's overall experience that the thinner the topsoil, the poorer the reclamation. Sometimes this cannot be helped due to the lack of topsoil prior to mining, however, this site has adequate topsoil available to enhance the final reclamation product. From review of the baseline soils information, and the fact that there will be a major surplus of topsoil available, the replacement depths should be increased to 12-18 inches with a minimum replacement depth of 12 inches. Please identify the amount of topsoil that will be stripped and show the locations of the stockpiles on the mine plan or extraction plan maps. This should include the proposed locations of the visual screens, other topsoil stockpiles, and overburden stockpiles. WATER Potential impacts to the surrounding surface and groundwater users have not been adequately evaluated at this point. Rule 3.1.6 requires disturbances to the prevailing hydrologic balance, of the affected land and surrounding area, and to the quality and quantity of water in surface and groundwater systems both during and after mining and during reclamation, to be minimized. The division is awaze that the operator is working with adjacent landowners to address concerns that have been raised and offers the following comments for consideration and or compliance with the act. The mine plan calls for dry-mining the site meaning that the "active pit" will be de- watered during mining. Absolutely no information has been submitted to indicate how this mining method will minimize groundwater impacts to adjacent landowners as stated in the application. It seems rather obvious that this activity will cause a cone of depression to radiate out from the pit and under adjacent property. The resulting potential impact to domestic wells, irrigation wells, wetlands, and surrounding vegetation has not been cleazly projected. In order for the division to determine that potential disturbances to the hydrologic balance will be minimized, the applicant must provide additional information demonstrating what the impacts could be and how they will be mitigated. This will likely involve gathering existing data or obtaining new data in order to conduct some modeling that will project the behavior of the surface and groundwater regimes in the azea once mining has reached its maximum disturbance. In addition, once these projections have been made, there should be a plan which will quantify the damage threshold that will initiate remedial actions and what those remedial actions will be for each potential impact. For instance, for a neazby domestic well, the plan may include static well level monitoring with a remedial plan of providing drinking or irrigation water if the static level drops below a certain point. This would probably continue until mining is completed and the static level has re-established to its pre-mine condition. The tolerance threshold and remedial actions will obviously be different for different structures such as an irrigation well versus wetlands. This will need to be done for each structure or system that is determined to be potentially impacted based on the information that will be forthcoming. Once these damage pazameters aze set, the operator should probably enter into damage agreements with the affected owners similar to the damage