2010-03-17_REVISION - M2000156 (6)

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6.4.5 Exhibit E - Reclamation Plan stabilizes (approximately 24 hours) before stripping and placing clay liner material. Field testing shall be performed during construction by a qualified geotechnical engineer as specified in the Construction Quality Assurance Plan (CQAP) (see below). The weathered shale borrow material shall be excavated by ripping 8 inches at a time of weathered shale off the bottom of the mined areas using a D8 ripper, or equivalent. The ripped weathered shale shall be spread and the dry density and moisture content shall be measured using ASTM D2922 and D3017 - Standard Test Method for Density and Water content of Soil and Rock in Place by Nuclear Methods. The dry density and moisture content measurements shall be used in the following equation to estimate the volume of water to add to the ripped material to obtain the specified moisture content: Vwater add - Vsoil [0.08*Pin place - 0.43*Winitial * 7 in place Where: Vwater add = volume of water to add (ft) Vso;i = volume of soil (ft) 7 in place = in-place density of soil (pcf) Winitial = in-place moisture content The water shall be added using a water truck that evenly distributes water across the excavated material. The moisture treated excavated material shall be disked to prevent clods from forming. The preparation and moisture conditioning process shall be repeated until optimum moisture content is achieved. Once optimum moisture content has been achieved the borrow material shall be collected by a scraper or equivalent vehicle Compacted Clay Liner Construction A backhoe will be used to dig a trench or keyway into bedrock. Weathered shale will be backfilled and compacted into the keyway as described below. The compacted clay liner material shall be placed to meet design lines, grades, and dimensions, as shown in Exhibit F, Typical Cross Section. The compacted clay liner material shall be placed using a scraper or equivalent vehicle in lifts with a maximum loose lift thickness of 9 inches. The maximum loose lift thickness may be increased to that recommended by the compaction equipment manufacturer as long as adequate compaction based on in-place density tests is met throughout the entire lift thickness, or as approved by the CQAP Monitor. The compacted clay liner loose lifts shall be compacted by tracking a minimum of six passes with a sheep's foot roller (Caterpillar 316 or similar) or CQAP Monitor