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Subsidence Field Observations <br />West Elk Mine <br />July 22-24, 2003 <br />• Traversed above the un-mined part of longwall Panel 17, which is locally within the area of <br />influence of the longwall pillar line. As of the date of traverse, the longwall pillaz line is 300 <br />to 500 feet east of the traverse line. <br />• This drill road exposes primarily colluvium and soil. <br />• The overburden thickness to the B-Seam ranges from 1,550 to 1,650 feet. <br />• No subsidence cracks or bulges were observed. <br />4.2.8 Traverse M-M' <br />The traverse begins at Drill Hole SOM-54 (Point J') and ends at Methane Drainage Well Site <br />MDW-17-08. <br />• This pre-mining traverse goes westwazd 1,200 feet thence northward 2,700 feet to the <br />western, un-[Wined part of longwall Panel 17. The last 500 feet of the traverse is located <br />above the un-mined part of longwall Panel 17. <br />• Soil and colluvium occur in the drill road cut. The soil is a rich, brownish color. <br />• Overburden thickness to the B-Seam ranges from 1,350 to 1,450 feet. <br />• No pre-mining cracks (pseudo-subsidence features) were observed. <br />831-032.610 Wright Water Engineers, Inc. Page 24 <br />September 2003 <br />