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subject to revision in the future based upon more accurate data. Should the actual swell <br />factor be significantly greater or less than the current estimated, then the mine and <br />reclamation plans will be amended and submitted to the Division. The profile survey will <br />be conducted on an annual basis, when mining resumes. <br />Prior to placement of material in the permanently reclaimed spoils area (box cut spoil), and <br />after the removal of soil materials, the applicant placed a sandstone underdrain in the <br />bottom of the spoil. The size of the underdrain was as designed with no less than I S feet <br />of sandstone, more than 2 feet m diameter, and had the following approximate size <br />distributions which were confirmed during placement: <br />2' - 1': 40% <br />4"-0:15% <br />As described in the hydrologic section, the sandstone which underlies most of the spoil has <br />no identifiable permeability. Consequently, no water will flow into the sandstone from the <br />spoil or into the spoil from the sandstone. There is no groundwater in the base of the spoil <br />as discussed in previous material and demonstrated by drilling data. <br />Surficial waters and infiltrate that exist along the drainage will be discharged via the <br />underdrain. Since construction of the underdrain, mine personnel have observed that the <br />underdrain is functioning as designed. Small flows have been observed in wet and spring <br />runoff periods. <br />Permanently Reclaimed Spoil Area <br />The permanently reclaimed spoil area is approximately 8.56 acres. The location of this <br />area is shown on Map 5-10. As described earlier, this azea consists of box cut spoil, <br />blasted sandstone, and overburden material (primarily alluvial terrace sands and gravels) <br />excavated to access the North Pit and the South Pit prior to achieving the steady-state pit. <br />As the spoil filled a segment of the original Carbon Junction Canyon drainage channel, <br />CDMG required OEI to design and construct the spoil area as if it was an engineered fill, <br />meeting all the requisite performance standazds. The final configuration of the <br />permanently reclaimed spoil area blends into the adjacent slopes of the permit azea and <br />provides complimentary topography for the adjacent golf course. Slopes are 3:1 (h:v) or <br />less and drain towazd Carbon Junction Canyon. Spoil placement was in four foot lifts <br />which were compacted to specified tolerances. Attainment of adequate compaction and <br />the grade and slopes involved will ensure that saturation and slope failure will not occur <br />(See Stability Study, Appendix 5-6). A designed underdrain was placed prior to spoil <br />deposition. <br />One ephemeral seep has been located southeast of the Permanently Reclaimed Spoils Area <br />and northwest of the South Pit, adjacent to the pit access road. Inspection of the seep in <br />TR08, TRl 1, TR12 (v1.0) 5-19 Revised 9/97, 08/02, 9/03 <br />