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storage facilities and were not specifically designed or constructed as impoundments, the applicable requirements
<br />of Rule 4.05.9 are addressed in this context by the following descriptions and the referenced existing configuration
<br />drawings:
<br />Area 1 Pit Temporary Water Storage Basin (TROS-47) -The Area 1 Pit is a remnant surface mine pit adjacent to
<br />the Run-of--Mine Coal Stockpile), as shown on Map 24, Surface Facilities, and by Figure EX8v-1 in Exhibit 8V.
<br />Impoundment design, operation, maintenance, and reclamation information is provided in Exhibit 8v. The remnant
<br />pit area is a totally incised excavation, enclosed by undisturbed natural ground and backfilled surface mine spoils,
<br />with an estimated maximum water storage capacity of approximately 200 acre-feet. The pit area is used for
<br />temporary storage of excess mine water, as part of the closed-loop mine dewatering and recycle system. Water
<br />inputs to the pit are limited to spoil spring discharge from the adjacent reclaimed spoils areas, excess dewatering
<br />flows from the mine dewatering systems, and minor incident precipitation. An upgradient diversion ditch (Ditch D-
<br />3) intercepts any surface runoff from upgradient reclaimed surface mine areas and routes it around the Area 1 Pit to
<br />Pond D. While a small culvert outlet at the low point on the crest of the pit allows for minor discharge flow to
<br />Pond D if the water reaches this level, the temporary storage basin is normally managed to keep water levels well
<br />below the discharge pipe. A fixed pumping station is used to control water level, with discharge to a de-sander,
<br />located at an old well site, and then to Washplant I or the mine water recycling system, or directly to Pond D for
<br />discharge to Foidel Creek. Management of the Area 1 Pit storage basin involves regular inspection and
<br />maintenance of water levels and pumping systems, and reduction of water levels prior to spring discharge to
<br />provide additional water storage capacity for any minor increases in subsequent spoil spring discharge.
<br />With implementation of operations for Washplant II, the Area 1 Pit is also utilized as the primary source for plant
<br />make-up water. An additional pump will be placed in the Area 1 Pit and connected to the new 8-inch water-line.
<br />Either a float or submersible pump will be utilized, with pump control and access from the existing pump-station access
<br />in the Area 1 Pit. A manhole with manual valves or automated control valves will be used to control flow to the
<br />Washplant. In order to address increased mine dewatering requirements, transfer pipelines from the Fish Creek and
<br />l ORT dewatering boreholes have been established, with discharge directly to the Area 1 Pit.
<br />Washplant I Thickener Overflow Sump (TROS-47, Superseded by TR07-59, Washplant II) -The Washplant 1
<br />Thickener Overflow Sump, located adjacent to the Thickener Tank in the Washplant I area, as shown on Map 24,
<br />Surface Facilities, and by Figure EX8w-1 in Exhibit 8w was excavated during Washplant construction to serve as a
<br />catch basin for the contents of the Thickener, if required for maintenance or under upset conditions. Impoundment
<br />design, operation, maintenance, and reclamation information is provided in Exhibit 8w. While it has not been
<br />necessary to utilize the basin for this purpose, it is occasionally used to collect and retain minor quantities of
<br />Washplant wash-down water. As an incised and closed basin (ie: no outlet) the only inputs are thickener overflow,
<br />wash-down water from the Washplant, or minor incident precipitation, which are subsequently pumped back into
<br />the system by a portable floating pump installation. Water level in the sump is monitored and managed as part of
<br />the ongoing plant operations.
<br />Washplant II Thickener Overflow Sump (TR07-59, Washplant II) -For discussion of Washplant II Thickener
<br />Overflow Sump please refer to previous discussion under Rule 2.05.3(3), Mine Facilities.
<br />FCB Treatment Facility (Revised - MR07-216)
<br />Three treatment cells were constructed for treating mine discharge water from the Fish Creek Borehole. The cells
<br />location and cross-sections are shown on Maps 26 and 32, Fish Creek Borehole Area Facilities, and Access Road,
<br />and Fish Creek Settling Pond Plan View and Cross Sections. The design for the culverts for the Fish Creek
<br />Borehole Access Road is presented in Exhibit 8R.
<br />The facility originally consisted of two adjacent dewatering wells. A water treatment system consisting of three
<br />treatment cells, chemical feed stations (sodium hydroxide and sulfuric acid), a substation, access road and
<br />powerlines, was subsequently added. The facility was modified in 2006, to replace the sodium hydroxide treatment
<br />system with an electro-coagulation unit. In 2007, the inactive Fish Creek Ventilation Shaft was converted to a
<br />dewatering installation to replace the inoperable Fish Creek South Dewatering Borehole. The water supply pumps
<br />are set within the dewatering wells immediately above the top of the coal seam in sealed mine workings in the
<br />Western Mining District. Electricity is supplied by the powerlines shown on Map 39, Powerline Location. Each
<br />TR09-66 2.05-79 04/11/09
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