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VI. Ground Water Hydrology -Rules 2.04.5, 2.04.7, 2. and 5 Information pertaining to ground water hydrology can be found on pages 58-70 of the permit application. Two ground water systems exist within the permit and adjacent area: conventional bedrock ground water and the alluvial ground water to be discussed in Section VII, Alluvial Valley Floors of this document. The existence of conventional bedrock ground water can be ohserved three ways: ground water monitoring wells, springs and seeps, and flow into the underground workings. Monitoring wells controlled by adjacent mines show that the only regional ground water aquifer existing within this permit area is the Tow Creek Sandstone, As shown on Figure 1 of this document, the Tow Creek Sandstone is separated from the coal seam to he mined by 600 feet of interbedded sandstones, shales and siltstones. These units have a very low vertical permeability, except possibly where faulted, Sunland conducted a spring survey to observe other possible ground water aquifers in the permit and adjacent area. The spring survey (Map Exhibit P of the permit application) identified several springs in and adjacent to the permit area. These springs within the permit area and those to the northwest near Middle Creek do not appear to be fault or fracture controlled. Rather, they appear to be stratigraphically controlled, perched aquifers, This conclusion is substantiated by the lnw electro-conductivity indicating a short flow path hetween the recharge and discharge areas. These springs, located one-half mile northwest of the mine workings, are the only springs that could be impacted by mining, Some minor effects to the quantity of flow from these springs might be realized due to subsidence above the workings. To date, ne problems have been noted with these springs. If a worst-case analysis assumes that all of the flow from the springs would be interrupted, the resultant flow reduction in Middle Creek would be 0.02 cubic feet per second, This amount is insignificant to the flow of Middle Creek. A mine inflow study was also undertaken by Sunland. This information is provided on Map 1 of the permit application. This map shows that the mine inflow is restricted to floor seeps occurring in Fault Block Nn. 1 and the total rate of water production underground is 40 gallons per hour, An underground inspection of the mine was conducted by the Division which confirmed that absolutely no water was being made th m ugh the fault zones even in areas where the mine is lower than Trout Creek stream level, Amine sump water sample was taken and the analysis is presented on page 59 of the permit application. This analysis shows acceptable water quality as defined for the Trout Creek drainage by the Colorado Departrre nt of Health, Water Quality Control Commission, The mine inflow study and sump water analysis will be conducted on an annual -10-