Laserfiche WebLink
There is minimal potential for the operation to deplete the quantity of flow in Munger Creek <br />and East Salt Creek, due to the limited disturbance acreage, sealed status of the portals, and <br />existence of only a single small impoundment, with water storage of less than 1 acre-foot. <br />The pond will be dewatered following any major storm event, thereby returning stored runoff <br />to the system. Due to the low annual precipitation in the area, it is expected that very little to <br />no water will be stored in the impoundment most of the time. <br />Very little ground water was encountered during exploratory drilling in and adjacent to the <br />permit area. There has been no discharge of mine water, due to the limited extent of mine <br />workings and the sealed status of the mine. Some depletion of surface water by infiltration <br />into the mine workings through natural and mine-induced fractures may occur. The amount <br />of depletion would be minor due to the steep local topography and low precipitation. The <br />slope varies from 2v:1 h to 6v:1 h. <br />The very low amount of surface water runoff that does occur is concentrated in periods of <br />snowmelt and thunderstorm events. These events produce short duration, high volume <br />runoff which, when coupled with the steep topography, greatly favors surface water runoff <br />over the infiltration of water. <br />No wells or springs were identified in Munger Canyon and no ground water rights have been <br />adjudicated within a three-mile radius of the Munger Canyon Mine. There is, therefore, no <br />potential for damage to the quality and quantity of ground water in the mine plan and general <br />areas. <br />The Loma loadout is situated within the D&RGW Railroad right-of-way. It occupies an area <br />historically used for loading sugar beets onto railroad cars. The disturbed area of the loadout <br />is approximately 2.9 acres. <br />All surface water at the loadout drains to a depression at the southeast corner of the disturbed <br />area. The disturbed area is bermed, with a small a silt fence installed adjacent to the low area <br />for filtering of any overflow. Due to the low precipitation experienced in the area (8.8 inches <br />annually), runoff is infrequent, and the small area exemption sediment controls described <br />have proven effective. <br />Due to the small area and low precipitation, little effect on the local hydrologic balance is <br />anticipated. There are also no operations in the area of the loadout that would produce a <br />cumulative effect on the hydrologic balance (the facility is approximately nine miles from <br />any mines). <br />Surface water is monitored upstream and downstream of disturbances in the Munger Canyon <br />drainage and along East Salt Creek above and below the confluence with Munger Canyon. <br />Monitoring locations are shown on Figure 2.3-5 of the permit application. Alluvial ground <br />water will be monitored downgradient of the proposed waste disposal pile in Munger Canyon <br />and in the Salt Creek alluvium upgradient and downgradient of the Munger creek confluence. <br />The monitoring program will indicate if any change in surface water and ground water <br />28