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2006 Subsidence and Geologic Field Observations <br />Box Canyon, W est Flatiron, Apache Rocks, and South of Divide Mining Areas <br />4.7 Traverse H-H' <br />Traverse H-H' begins at the fork in the drill roads (at G'}, follows a winding drill road, and ends <br />at MDWs 17-08-b and 17-08-c (now abandoned). The drill road trends south, then west, and <br />then northward above mined longwall panels 14 through 17. The overburden thickness varies <br />from 1,450 to 1,600 feet (see Map 1). <br />The material observed in roughly the first half of the traverse was weathered and fractured <br />siltstone, claystone, and sandstone of the Barren Member of the Mesaverde Formation. The <br />~ bedrock in the road cut appeared similar to pre-mining conditions, except that it looked more <br />weathered. colluvium and light gray to brown soil, an estimated 3 to 5 feet deep, were exposed <br />in the road cut in the last part of the traverse. No subsidence features were observed. <br />' 4.$ Traverse I-I' <br />Traverse I-I' begins at the fork in the drill roads (at G' and H) above the southern edge of mined <br />longwall panel 14 and ends at well site E-Seam Methane Exploration Well (ESM) No. 1. ESM-1 <br />' and ESM-2 (located along traverse J-J') were drilled since July of 2005 to determine the presence <br />of methane in the E-Seam <br />Traverse I-I' winds its way above mined longwall panels 14, 15, 16, 17, 13-A, and 13. Light <br />' gray to brown soil, colluvium, and local outcrops of siltstone and sandstone of the Barren <br />Member of the Mesaverde Formation occur in the road cuts. Overburden depth to the B-Seam <br />t varies from 1,000 to 1,650 feet. No subsidence features were observed. <br />4.9 Traverse J-J' <br />' Traverse J-J' begins at ESM-1 (and point I' of traverse I-I'), goes past ESM-2, and ends near <br />Apache Rocks. This traverse switchbacks above mined longwall panels 13, 13-A, and then 13 <br />again. <br />This traverse is on a road that transects gray to light brown soil, colluvium, and sandstone of the <br />' Barren Member of the Mesaverde Formation. The overburden depth to the B-Seams varies from <br />' 831-032.750 Wright Water Engineers, Inc. Page 23 <br />December 2006 <br />