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sodium/bicarbonate down gradient. Well 3WC displayed the only case of elevated iron levels within the Wolf Creek coal. Well 2WC located down gradient has the lowest levels of TDS and sulfate, indicating that the sulfate is being precipitated from the water as it moves down gradient. Two wells were established to monitor water levels and quality in the seam within the south extension area, down-gradient of mining areas (4WC and WWC24). Water levels at 4WC are generally over a hundred feet deeper than the adjacent Wadge Coal Well 4W, indicating no hydraulic communication between the two units. 4WC was sampled 1983 to 1985 to establish baseline conditions, and sampling was resumed in 1997 for monitoring purposes. The well displays a MgCa-HCO,SO, type water with average TDS value of 812 mg/1. Due to safety concerns because of proximity to the highwall, the well was abandoned in 2003 and will be replaced in 2004. Well WWC24 was drilled in August 2001 but was damaged by landslide in the spring of 2003, and subsequently abandoned. A replacement well was drilled in the summer of 2004. WWC24 was a flowing well. Initial samples displayed a Na-HCO, type water with TDS values of 640 and 820 mg/1. Wolf Creek/Wadge Interburden Seneca installed one well (3EI) to monitor the interburden within the original permit area. The interburden consists of 165 to 215 feet of interbedded sandstone, shale, siltstone and coal, thus forming a relatively impermeable zone between the underlying Wolf Creek coal and the overlying Wadge coal. Monitoring data for the well were presented in the permit application. Depth to water measurements at this well were made for about 22 months. This data not only shows very little seasonal fluctuation, but that the interburden at this site is under unconfined or water table conditions. This is not an expected characteristic because both the Wolf Creek coal and the Wadge coal, at least seasonally, exhibit artesian head at this site. It is possible that this well was no[ properly completed, or that a perched aquifer was intercepted by the well. Seneca Coal Company has subsequently abandoned this well. Based on analysis of the Wolf Creek and Wadge coal, it is expected that water within the interburden, as in the other units, will exhibit confined conditions downdip of the Sage Creek anticlinal axis. No water quality sampling was done in the interburden, in the original permit area. Refer to discussion related to Sage Creek overburden and Wolf Creek overburden regarding sampling of strata below the Wadge seam within the south extension area. Seneca II-W Findings Document 31 November 17, 2004 Permit Revision No. 4