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<br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br />1 <br />previous year. Longwall Panel 1 (LW-1) was mined to within about 900 feet of this location in <br />February 1988. <br />Water level at monitor hole 4-20U dropped 2.3 feet from the previous year's reading. <br />Wells 29-4U, 30-8U, 32-7U and 33-8U are located within Federal leases C-8424 and C-8425. <br />Only B-Seam will be mined within these leases. No mining has taken place near these wells <br />except within 600 feet of well 32-7U (longwall development in B-Seam). Any fluctuation in the <br />water level is probably only seasonal. <br />The data collected during this water year continues to demonstrate that there is very limited <br />vertical permeability between the upper and middle monitoring zones. <br />The "siltstone-coal facies" monitoring holes are designated by an "M" following the hole <br />number. These monitor holes are open through the interval containing the D Seam and B <br />Seam. <br />Monitor hole TW2-17M was by-passed by mining first in November 1985 but was not <br />intercepted in the workings. It is apparently located in a pillar completely surrounded by open <br />workings. At that time it showed virtually no response to room-and-pillar mining. In February <br />1988 longwall panel 1 was mined to within about 900 feet of this hole. Obviously, longwall <br />mining disrupts the mined zone more than room-and-pillar mining, and the water level in <br />TW2-17M did show a response to mining at that time. The water level decreased 39.7 feet <br />during the 1998-1999 period showing a significant change probably due to the mining of LW- <br />12. <br />Well 29-4M showed a decrease of 4.4 feet in water level. This well is 1.5 miles away from the <br />' nearest mine working. Hence, the water level drop is probably only seasonal. No noticeable <br />water level change occurred in wells 30-8M, 31-7M and 32-7M. Well 33-8M showed an <br />' increase of 4.3 feet. <br /> <br />1 <br /> <br /> <br />The hydrographs of the "lower sandstone facies" are designated by the letter "L" following the <br />hole number. The original hole 2-17L was plugged in early fall 1985 as it was feared the mine <br />would intercept it. As it turned out, the hole was never encountered in the workings. As <br />required by DMG, a new hole was drilled and completed in the "lower sandstone facies". <br />From the time the new hole was completed, the water levels in this hole have fallen. During <br />May 1986, mining in gate road 2nd East intercepted an exploration hole, (21012-9) that had <br />been drilled in 1978. This hole had been plugged with heavy mud but leaked from both the <br />mine roof and floor when the hole was intercepted. Water flow from the hole in the roof <br />was about 3 gpm (gallons per minute) and was plugged with a packer. The flow from the <br />6 <br />1 <br />