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2.05.6 <br />The flooded mine workings could also affect the ground water quality and quantity in <br />the overlying Upper and Lower Perched Water Zones. However, as stated above, <br />the Mesaverde Formation transmits little water. Therefore, the impact the flooded <br />mine workings will have on the quantity and quality of the surrounding strata should <br />be minor. <br />The Rollins sandstone, as monitored in DH -34B, NM4X98 -29 and P- TC- 03 -01(R) <br />has pH in the range of 7.5 to 9.6, conductivity in the 1,200 to 7,900 umhos /cm range <br />and total recoverable iron in the 0.2 to 62.0 mg /I range. The Rollins sandstone is a <br />confined aquifer under piezometric head. The confining shale layers above the <br />sandstone and piezometric head should prevent any integration of water from either <br />the D -Seam or B -Seam into the Rollins sandstone. There are two drill holes G -15 <br />located near the mouth of Dove Gulch and DH 98 -57 located in the central portion of <br />the mine workings that provide documentation of the hydraulic isolation of the Rollins <br />sandstone from the B -1 Seam, the lowest coal seam to be mined. In G -15 and DH <br />98 -57 there are 77.0 and 85.1 feet respectively of identified shale, sandstone and <br />coal between the B -1 Seam to near the top of the Rollins Sandstone. In the western <br />mine plan area, drill holeTC -03 -03 documents the isolation between the Rollins <br />sandstone and the B -2 Seam, the lowest coal seam to be mined. In TC -03 -03 there <br />are 23 feet of mudstone, 28.3 of sandy mudstone, 4.0 feet of sandstone and 19.2 <br />feet of coal between the Rollins sandstone and the B -2 Seam. Map 08 provides drill <br />logs of the three drill holes that demonstrates the hydraulic isolation of the Rollins <br />Sandstone. The perched water below the D -Searn and above the B -Seam is or was <br />monitored by drill holes D -58a and DH- 67- D -Blw. The quality of water in this <br />perched water being zone, as reported in the 2007 AHR show pH in the range of 7.8 <br />to 11.6, conductivity ranges from 485 to 5030 umhos /cm and total recoverable iron <br />ranges from 0.03 to 31.4 mg /I. Based on the quality of the mine water discussed <br />above, mine water seepage into the perched water below the D -Seam and above the <br />B -Seam would improve the water quality in the perched water bearing zones. <br />The perched water above the D -Seam is or was monitored by drill holes D -58, 66 <br />and DH- 67- D -Abv. The quality of water in this perched water being zone, as <br />reported in the 2007 AHR show pH in the range of 6.9 to 13.5, conductivity ranges <br />from 652 to 5500 umhos /cm and total recoverable iron ranges from 0.08 to 17.7 <br />mg /I. Based on the quality of the mine water discussed above, mine water seepage <br />into the perched water above the D -Seam would improve the water quality in the <br />upper perched water bearing zone. <br />• <br />TR -65 2.05 — 75ii 02/10 <br />A Pppo VC 0 <br />L, #61,o <br />