Laserfiche WebLink
The Division has no further concerns. Page 4 was revised in the October 1, 2009 submittal. <br />6. The fourth paragraph on Page 4 includes details regarding topsoil and coverfill quantities <br />salvaged for the CMWDA-2. Please provide similar details for CMWDA-4 in the fifth paragraph. <br />The Division has no further concerns. The October 1, 2009 submittal contained a revised page 4 <br />7. In the first paragraph of Page 13, the reader is referred to the November 2003 Lambert & <br />Associates study. Please modem this paragraph to reference the "various " geotechnical studies <br />following the section. <br />The Division has no further concerns. Page 13 was revised in the October 1, 2009 submittal. <br />8. CMWDA-4 has been designed with the intention offirst excavating native soils in order to create <br />an available area for placement of the coal mine waste. The Buckhorn Geotech report dated <br />February], 2007 evaluated overall excavation slopes of 2.5H.•I V and 2H.•I V. These slopes <br />resulted in acceptable upper waste fill slopes of 2.5H.•I V and 3H.•I V, respectively (page 3, 5"' <br />paragraph). The May 2009 Buckhorn Geotech report steepens the acceptable excavation slope <br />(assuming a 3:1 upper waste fill slope of 3H.•I V) from 2H.•I V to 1.3H.•I V. Presumably it is this <br />steepening of the acceptable excavation slope that accounts for much of the potential increase in <br />the volume of CMWDA-4. Section D-D' of Volume LV Figure 1 illustrates the relative locations of <br />the original ground surface and the proposed ground surface. Missing from this Section is aline <br />showing the proposed excavation surface. Please modify Section D-D' to represent the <br />approximate limits of excavation that have preceded or are expected to precede the placement of <br />coal mine waste in CMWDA-4. <br />The new location and information for Section D-D' on Figure 1 is appreciated. However, the <br />2H:1 V cut slope shown on the revised Section D-D' is shallower than what was determined to be <br />acceptable in the Buckhorn Geotech report. If the steeper (1.3H:1 V) cut slope was or will be <br />utilized, Section D-D' should be modified accordingly. <br />9. The map view of Volume IX Figure I seems to indicate that the northern portion of CMWDA-1 <br />has effectively been absorbed into CMWDA-4. This and other associated changes should be <br />reflected in Volume IV of the permit. <br />The Division has no further concerns. A reference to the location of the designs was added to page 5 <br />in Volume IV of the October 1, 2009 submittal. <br />Reclamation Cost Estimate Review <br />10. The operator is proposing to increase the size of Gob Pile #4 by increasing its maximum height, <br />lowering the elevation where it starts and increasing its acreage. Based on cross-section D-D, <br />the maximum height of the pile is being increased from 6,230' to 6,235' and the starting elevation <br />of the pile is being decreased from 6,110' to 6,080'. Asa result of these elevation changes, the <br />area of the pile is being expanded to the north and the south. Based on the Division's digitizing, <br />the area of Gob Piles #1 and #4 (taken together because they converge) increased from 10.3 acres <br />to 11.3 acres. The increases in area extend into what appears to be undisturbed lands both above <br />and below Gob Pile #4. BRL has not included any detail regarding the topsoil and subsoil <br />2