2019-01-31_REVISION - M1988108 - Laserfiche WebLink

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Ards,, ant ARCOSA Exhibit D—Mining Plan Shale feed for the lightweight aggregate plant is mined from an existing quarry located in Section 5, TIS, R70W. Prior to the initial issuance of Mining Permit No. 1988-108, the quarry was last mined by Great Western Aggregate Company in 1975 and was left unreclaimed as it was a prelaw operation. As reserves are depleted, the mining proceeds to the south by removing overburden to expose additional shale to feed the process plant. The removed overburden will be used directly in reclaiming the mined out portion of the quarry. Later, when mining operations cease, overburden that was previously stripped and stockpiled will be used to reclaim the area last mined. Mine Operations Mining progresses to the south incrementally. Each southward increment involves stripping overburden to expose additional reserves and placing this overburden on slope and the bottom of the mined out portion of the quarry. Then the newly exposed section is mined out to the ultimate quarry depth prior to stripping the next increment. The ultimate depth of the quarry floor elevation is 5,860 feet above mean sea level. Existing overburden stock-pile will be reserved for use in reclaiming the portion of the quarry last mined. Additional reclamation details are discussed in Exhibit E. Shale will be mined using an excavator to rip the material from the quarry floor and load it directly into off-highway trucks of 35-to 50-ton capacity. The trucks, in turn, haul the shale to a primary crusher (feeder-breaker)located at ground-level above the quarry along a haul road on the western side of State Highway 93 that traverses beneath the highway from west to east.After reduction to a nominal minus 5-inch size, the shale is transported by conveyor underneath SH 93 to the processing plant for further size reduction and storage. Subsequently, the material is fed into a rotary kiln where it is heated to 2,0000 F to produce lightweight aggregate. The mining plan currently calls for excavation of 1,200 to 1,400 tons of shale per day. The quarry will operate seven days per week beginning mining at 5:00 AM at the earliest to midnight at the latest, dependent upon operational demand and the safety of operating conditions. The lightweight aggregate plant will produce at least 200,000 cubic yards of aggregate annually for up to 30 years, depending on market and operational conditions. Runoff Control Precipitation runoff and any water which originates from seeps at the overburden-shale interface will be intercepted by a ditch and will be channeled around the pit to catchment ponds on the quarry floor. The location of this ponds will be shifted from time to time to permit uniform deepening of the quarry floor. Approximately 30,000 gallons per day of water will be pumped from the quarry to the processing plant for various purposes including dust suppression and scrubber water.