Laserfiche WebLink
Protection of Hydrologic Balance <br />~s specifically requested during the Permit Renewal 03 adequacy review, CYCC has again updated the probable <br />hydrologic consequence section as found here under the Protection of Hydrologic Balance. <br />Groundwater Hvdrolo2ic System <br />A detailed discussion of groundwater hydrology is presented under Section 779.15. The Eckman Park Mine <br />permit area is located on the southwest flank of the Twentymile Park groundwater basin. The Twentymile Park <br />Basin is an enclosed groundwater basin. As a result, any mining-related impacts on the groundwater hydrologic <br />system will be confined within the basin. <br />Potential Minine-Related Impacts on Groundwater Ouantitv and puality <br />The mining and related operations at the Eckman Park operation have the potential to locally affect the water <br />levels, +vater chemistry, and dissolved solids concentrations of the groundwater contained in the Wadge <br />Overburden sequence and the Trout Creek Sandstone aquifer. The Wadge Overburden will be directly affected as <br />•t result of removal and replacement of overburden materials during extraction of the Wadge coal seam. The Trout <br />Creek Sandstone aquifer may be indirectly affected due to a small proportion of recharge to this aquifer passing <br />through overlying disturbed materials. <br />The major groundwater effects of the mining operation will be on water quality within the undisturbed Wadge <br />Overburden downdip of the operation. Recharge of these bedrock units through backfilled areas will result in <br />significantly higher concentrations of dissolved solids and a change in water chemistry type. <br />Typical baseline TDS concentrations in the Wadge sequence average 600 mg/1 and the +rater type is a sodium <br />bicarbonate type as sltowtt by Permit Renewal Figure 3, Triangular Diagram Plot, Bedrock Groundwater. This <br />compares +vitlt a TDS concentration of about 4,000 mg/I in the backfill and a dominant calcium-magnesium-sulfate <br />water quality type as shown by <br /> <br />1996 Permit Ren. Permit Renewal 780-144-1 Revised 3/18/97 <br />