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Michael Boulay May 21.2008 <br />According to Rule 4.10.3(5), "an alternative subdrainage system may be utilized <br />after approval by the Division upon a thorough analytical demonstration that such <br />an alternative will ensure the applicable static safely factor, stability of the fill and <br />protection of the surface and groundwater in accordance with the requirements of <br />these Rules." Such an analytical demonstration has not been provided for the <br />Division's review. In fact, the Stability Evaluation prepared for the operator by <br />Buckhom Geotech, Inc. states that, "Foundation under-drains should be <br />designed and constructed to keep the near surface foundation soils drained. We <br />understand these drains are to be designed by others." <br />Please provide for inclusion in the application, either: 1) an analytical <br />demonstration in accordance with the requirements of Rule 4.10.3(5); or 2) <br />a design for a subdrainage system in accordance with the requirements of <br />Rule 4.10.3(1). <br />CAM: The Operator believes Rule 4.09.1(13) was applied correctly, please refer <br />to Rule 4.10.1(1)(a). Please see the attached Stability Evaluation prepared by <br />Buckhom Geotech. It appears an older version was sent out in the original <br />technical revision application. The new version included in this adequacy review <br />does not recommend that foundation under-drains should be designed as part of <br />the Coal Mine Waste Pile. It is important to also note, when water was <br />encountered during drilling, the shallowest was at 23.5'. The operator stands by <br />the initial application submittal that no springs or seeps have been discovered <br />and therefore an underdrain is not required, according the aforementioned Rule. <br />26. DRMS: Placement and compaction of the Coal Mine Waste, as described <br />on 2-27ii, is in general compliance with Rule 4.10.4, Construction Requirements. <br />There is however no basis presented for the proposed compaction testing <br />intensity of "a minimum of 1 compaction test for every other compacted lift". <br />Please include rationale/justification for the proposed compaction testing <br />intensity, including considerations such as the equipment to be employed <br />in grading and compaction operations, equipment operator experience and <br />consistency, projected rate of waste material accumulation and projected <br />variability with regard to waste material source, physical characteristics <br />and moisture content. (1 didn't address the highlighted areas) <br />CAM: Please see the Munger Canyon Permit Volume I, page 2-18 and the <br />Bowie No.2 Mine Volume IX, page 9. It is assumed by the operator since "a <br />minimum of 1 compaction test for every other compacted lift" is part of at least <br />two approved permits, to be a generally accepted practice by the Division. Also, <br />please see updated page 2-27ii regarding the type of equipment to be used and <br />operator experience. <br />27. DRMS: Rule 4.10.4(5) states that "following grading of the coal mine waste <br />bank, the site shall be covered with a minimum of 4 feet of-material." The <br />11