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(Attachment A) <br />General Ore Pad Construction Criteria <br />These are general guidelines for uranium ore stockpile pads for storage of ore up to 180 days. If longer term <br />storage is anticipated please contact the Division of Reclamation, Mining and Safety (DRMS) for further <br />review. <br />Ore Pad Construction: DRMS requires compaction for soil liners to 95 percent of maximum dry density <br />based on the standard Proctor. The number of Proctor tests required depends on the size of the pad and on <br />variability of the source(s) for soil liner fill. At least one Proctor must be taken on representative samples of <br />each soil type to be used, and additional Proctors for each soil type may be required for very large pads. The <br />frequency of required moisture/density tests on soil following compaction depends on the size of the project. <br />For large projects, one test per 500 cubic yards is appropriate, for smaller projects, one test per lift. <br />In order for soil to be effective as a liner it must behave plastically. The upper twelve inches of soil to be <br />compacted on the ore pad must have a minimum plasticity index of 10 percent. If there are no onsite soils <br />that meet this criterion, the Operator must use imported soil or soil amendments to increase plasticity, or <br />propose other liner alternatives for DRMS review and approval. The testing frequency for Atterberg Limits <br />depends on the size of the project and the variability of the soil source(s). A geotechnical engineer should be <br />consulted in the development of the testing frequency. <br />Specifications and testing frequencies may also be established for moisture content at the time of compaction <br />(compaction slightly above optimum moisture is desirable for soil liners), grain size distribution, and <br />permeability. <br />The Operator may not use the pad for ore storage until the compaction is complete and the DRMS has <br />reviewed and accepted the soil test results. Also, the Operator must periodically inspect the pad for <br />indications of desiccation and freeze/thaw effects that will increase permeability. If these effects are <br />observed, the upper twelve inches of soil must be reworked, moisture conditioned as needed, and compacted. <br />The Operator must report on ore pad inspections and any reworking of the pad soil liner in each annual <br />reclamation report. <br />Placement of the soil liner should have a temperature limitation. No frozen soil liner materials shall be used as <br />liner fill. Preparation of the native area should be a major consideration prior to placement of the soil liner fill. <br />It must be reasonably smooth and void of large rocks and objects. <br />These are noted as general guidelines. Site specific conditions may require additional tasks and tests. Ore pad <br />design shall be submitted as a Technical Revision or as part of the permit application or permit amendment. <br />Review and written approval prior to initiation of any construction shall be required. DRMS shall be notified <br />in writing 10 working days prior to construction so that a pre-construction inspection can be conducted and, if <br />need be, construction oversight scheduled. <br />(end)