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2007. The report is to be inserted into Volume XI. <br />20. Rule 4.09.1(!4) requires the submittal of a foundation investigation and laboratory testing of <br />foundation materials to show what designs are needed to ensure the stability of the coal waste pile <br />foundation. However, as mentioned in question no. 19 above, no foundation investigation and <br />laboratory testing of foundation materials has been performed. Please include the findings of a <br />foundation investigation and laboratory testing offoundation materials to support the design report <br />mentioned in the previous comment above. <br />The Division has no further concems. In the submittal dated April 4, 2007, BRL provided the <br />"Stability Evaluation of Proposed Coal Wastepile No. 3" by Buckhorn Geotech, dated Mazch 29, <br />2007. The report is to be inserted into Volume Xl. <br />21. Rule 4,10.4(2) requires that coal mine waste piles achieve a minimum static factor of safety of I.S. <br />A minimum static safety factor of 1.5 is demonstrated, but with assumed material characteristics <br />as mentioned in questions nos. 19 and 20 above. Please modify the application so as to <br />demonstrate applicability of the stability analysis provided. <br />The Division has no further concems. [n the submittal dated April 4, 2007, BRL provided the <br />"Stability Evaluation of Proposed Coal Wastepile No. 3" by Buckhorn Geotech, dated Mazch 29, <br />2007. The report is to be inserted into Volume XI. <br />22. Rule 4.09.1(13) requires that an appropriate underdrain be installed ifseeps, springs or waterways, <br />natural or manmade, are in the coal waste disposal footprint area. Even though there is no indication <br />in dhe application that springs, natural or manmade watercourses, or wet-weather seeps exist in the <br />footprint of the proposed pile, BR proposes, without cause, an underdrain. Please confirm if such <br />seeps, springs or waterways exist in the coal refuse footprint area. <br />The Division is prepared to approve the underdrain as proposed, even though there is no indication <br />that one is needed or serves any useful purpose. However, ifseeps, springs and waterways are not <br />present and if BRL prefers, the application can be worded such that the site is to be inspected for <br />springs or seeps as work progresses, and the drain installed only for cause. This would be an <br />alternate design as permitted under Rule 4.09.1(3) and 4.10.3(5). <br />Please consider the under drain design to be a contingency, based upon the inspection ofa certified <br />engineer ofthe prepared embankment footprint. Ifthere are no groundwater springs or seeps and no <br />natural drainage ways, then no under drain would be placed. If any are identified, the under drain <br />would extend from the toe of the embankment to the source of the seep. <br />The Division has no further concerns. Map 21-I, Map 21-3, Figure 1 and page 5 of Volume XI <br />were revised in the January 3, 2007 submittal to show that an underdrain is not required. <br />23. Rule 4./0.3(2) requires that any surface runofffrom the crest and face of the waste disposal area be <br />diverted in accordance with 4.09.1(7). However, the top surface ofthe pile as proposed is not diverted <br />