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• Ditch D-2 was relocated to the south, pazalleling the Refuse Haulroad, two culverts were added under the Washplant II yard-area access, and the eastern inlet to Sedimentation Pond D was shifted to the south and • west. Contributing watershed areas and conditions did not change significantly, ditch and culverts sizes were maintained, and ditch condition and configuration were improved, therefore, revised drainage calculations were not necessary. • Washplant construction would encroach on the existing Pond D emergency spillway, so the spillway was relocated to the center of the Pond D embankment, neaz the principal spillway. This location also improves pond function by increasing the distance between the pond inlets and emergency spillway and improving routing. As part of the design process, four soil borings were completed for design of the foundation structures for the major Washplant facilities (refer to Washplant II Foundation Design Report in Exhibit 25). Site backfill and grading work for Washplant II involved removal of potentially unsuitable soil materials, ripping and scarification of the entire Washplant pad area, cut and fill grading, and controlled placement and compaction. Cut volumes were approximately 24,000 cy, and approximately 12,000 cy of suitable fill and 10,000 cy of graded rock material were placed and compacted, consistent with the foundation design recommendations. Backfilled and compacted pad areas were then graded to direct surface runoff flows to the designed drainage and sediment control structures, and (except for building foundation aeeas) graveled to control erosion, dust, and surface drainage. Graveled aeeas will be utilized as yard-area driveways for equipment and operations/maintenance access to the Crushing/Sceening Building, Washplant, thickener, and Refuse Bin. Based on the foundation design recommendations, reinforced concrete caissons were poured to support building foundations and conveyor supports. Reinforced concrete floor slabs and grade walls were then formed and poured to connect to the concrete caisson support system. The initial segment of the existing Overland Conveyor was replaced with an inclined Cmshing/Screening Feed Conveyor (48-inch belt w/2,200 tph capacity) extending 920 feet from the Raw Coal Stockpile reclaim to the new Screening Tower. The inclined conveyor segment is supported by two steel support bents, and typical conveyor construction consists of a steel rail framework supporting the troughing and return idlers, with an adjacent cat-walk • and railings for maintenance, and'/< coverage galvanized steel covers to control dust and noise. The conveyor bents set on reinforced concrete caissons, as previously described. From the Crushing/Screening Feed Conveyor, the coal discharges through a chute and feeders to double-deck screens which sepazate the coal feed into three size fractions; an undersize fraction (-''/z" x 0") which passes through and discharges directly to the Overland Conveyor; an intermediate fraction (%z" x 2") which transfers to the Washplant Feed Conveyor; and the screen oversize (+2") which dischazges to aroll-crusher, with the crushed product transferring to the Washplant Feed Conveyor. By-pass chute-work allows the intermediate and crushed products to be diverted directly to the Overland Conveyor, if plant feed coal quality precludes the need for washing. The crushing and screening equipment, along with associated chute-work, and control, monitoring and dust collection systems, are housed in the Crushing/Screening Building, a steel frame building with steel siding and roof (50 x 60 x 80 feet high), which sets directly over the Overland Conveyor. The building sets on a reinforced concrete slab floor (52 x 62 x 1 foot thick) with grade walls connected to the concrete caisson support system, as previously described. A two-flight Washplant Feed Conveyor (48-inch belt w/2,200 tph capacity) and Transfer Tower (20 x 20 x 40 foot high) transfer the intermediate and crushed coal products from [he bottom of the Crushing/Screening Building to the top of the new Washplant II Building. The Washplant Feed Conveyor system is designed to handle current requirements of 1,300 tph, as well as possible futwe system expansion. Each of the two conveyor flights is supported by a single steel support bent, and utilize the typical conveyor construction. The conveyor bents set on reinforced concrete caissons, as previously described. The intermediate Transfer Tower is a steel frame building with steel siding and roof which contains minor chute-work and a dust collection system. The Transfer Tower sets on a reinforced concrete slab floor (22 x 22 x 1 foot thick). TR07-59 2.05-32.2 03/26/07