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Coal refuse from both the coarse and fine coal circuits is de-watered and <br />transferred to the respective fine and coarse refuse storage hoppers. <br />Fine coal refuse is difficult to dewater using conventional methods. As <br />a consequence, Dorchester installed a belt filter press to remove excess <br />moisture prior to disposal. <br />Coal preparation activities are graphically illustrated by Figure 17, <br />Preparation Plant Flow Sheet. In addition, coal preparation systems, <br />methods, and equipment are described later in this section under the <br />subtitle, "Mine Facilities". <br />Coal Refuse Disposal. Coal processing waste including both coarse and <br />fine size fractions is collected in hoppers located in the preparation <br />plant area. Periodically, rear dump haulage trucks remove coal refuse <br />materials from these hoppers and haul refuse materials to a permanent coal <br />refuse stockpile located west of the mine facilities and portal area as <br />shown by both the Mine Plan Map (Map 17) and Mine Surface Facilities Map <br />(Map 18). Coarse and fine refuse materials are dumped, placed, and <br />• compacted in successive lifts approximately 24 inches thick. An expanded <br />discussion of design, construction and reclamation of the coal refuse pile <br />is presented later in this section under the subtitle, "Mine Facilities". <br />Water Treatment. Process water from the coal preparation plant may <br />exhibit elevated TSS, TDS and levels of certain chemical constituents. <br />With elevated values which may exceed applicable effluent limitations, <br />process water is contained within a closed loop circuit and is not allowed <br />to discharge to the surface drainage system. The closed loop process <br />water circuit includes the preparation plant process water system, <br />clarifier, and Water Treatment and Recycle Pond No. 2. Primary treatment <br />of process water occurs in the clarifier where fine coal material is <br />removed from the process water stream. Clarified process water is then <br />transferred to Water Treatment and Recycle Pond No. 2. Pond No. 2 is a <br />lined non-discharging pond where flocculants or other chemicals may be <br />added as necessary to cause remaining suspended solids to settle out and <br />to modify pH or reduce concentrations of specific chemical constituents. <br /> <br />C:\WORI(\PRf9W8N1fR15 REV <br />a~~~~ 2.05.3-14R Revised - April 1993 <br />