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storage facilities and were not specifically designed or constructed as impoundments, the applicable requirements of Rule
<br />4.05.9 are addressed in this context by the following descriptions and the referenced existing configuration drawings:
<br />Area 1 Pit Temporary Water Storage Basin (TR05-47) — The Area 1 Pit is a remnant surface mine pit adjacent to the Run -
<br />of -Mine Coal Stockpile), as shown on Map 24, Surface Facilities, and by Figure EX8v-1 in Exhibit 8V. Impoundment
<br />design, operation, maintenance, and reclamation information is provided in Exhibit 8v. The remnant pit area is a totally
<br />incised excavation, enclosed by undisturbed natural ground and backfilled surface mine spoils, with an estimated
<br />maximum water storage capacity of approximately 200 acre-feet. The pit area is used for temporary storage of excess
<br />mine water, as part of the closed-loop mine dewatering and recycle system. Water inputs to the pit are limited to spoil
<br />spring discharge from the adjacent reclaimed spoils areas, excess dewatering flows from the mine dewatering systems,
<br />and minor incident precipitation. An upgradient diversion ditch (Ditch D-3) intercepts any surface runoff from upgradient
<br />reclaimed surface mine areas and routes it around the Area 1 Pit to Pond D. While a small culvert outlet at the low point
<br />on the crest of the pit allows for minor discharge flow to Pond D if the water reaches this level, the temporary storage
<br />basin is normally managed to keep water levels well below the discharge pipe. A fixed pumping station is used to control
<br />water level, with discharge to a de -sander, located at an old well site, and then to Washplant I or the mine water recycling
<br />system, or directly to Pond D for discharge to Foidel Creek. Management of the Area 1 Pit storage basin involves regular
<br />inspection and maintenance of water levels and pumping systems, and reduction of water levels prior to spring discharge
<br />to 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 make-
<br />up water. An additional pump will be placed in the Area 1 Pit and connected to the new 8 -inch water -line. Either a float or
<br />submersible pump will be utilized, with pump control and access from the existing pump -station access in the Area 1 Pit. A
<br />manhole with manual valves or automated control valves will be used to control flow to the Washplant. In order to address
<br />increased mine dewatering requirements, transfer pipelines from the Fish Creek and IORT dewatering boreholes have been
<br />established, with discharge directly to the Area 1 Pit.
<br />Washplant I Thickener Overflow Sump (TR05-47, Superseded by TR07-59, Washplant II) — The Washplant 1 Thickener
<br />Overflow Sump, located adjacent to the Thickener Tank in the Washplant I area, as shown on Map 24, Surface Facilities,
<br />and by Figure EX8w-1 in Exhibit 8w was excavated during Washplant construction to serve as a catch basin for the
<br />contents of the Thickener, if required for maintenance or under upset conditions. Impoundment design, operation,
<br />maintenance, and reclamation information is provided in Exhibit 8w. While it has not been necessary to utilize the basin
<br />for this purpose, it is occasionally used to collect and retain minor quantities of Washplant wash -down water. As an
<br />incised and closed basin (ie: no outlet) the only inputs are thickener overflow, wash -down water from the Washplant, or
<br />minor incident precipitation, which are subsequently pumped back into the system by a portable floating pump
<br />installation. Water level in the sump is monitored and managed as part of the ongoing plant operations.
<br />Washplant II Thickener Overflow Sump (TR07-59, Washplant II) — For discussion of Washplant II Thickener Overflow
<br />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 location
<br />and cross-sections are shown on Maps 26 and 32, Fish Creek Borehole Area Facilities, and Access Road, and Fish Creek
<br />Settling Pond Plan View and Cross Sections. The design for the culverts for the Fish Creek Borehole Access Road is
<br />presented in Exhibit 8R.
<br />The facility originally consisted of two adjacent dewatering wells. A water treatment system consisting of three treatment
<br />cells, chemical feed stations (sodium hydroxide and sulfuric acid), a substation, access road and powerlines, was
<br />subsequently added. The facility was modified in 2006, to replace the sodium hydroxide treatment system with an
<br />electro -coagulation unit. In 2007, the inactive Fish Creek Ventilation Shaft was converted to a dewatering installation to
<br />replace the inoperable Fish Creek South Dewatering Borehole. The water supply pumps are set within the dewatering
<br />wells immediately above the top of the coal seam in sealed mine workings in the Western Mining District. Electricity is
<br />supplied by the powerlines shown on Map 39, Powerline Location. Each
<br />TR18-91 2.05-79 08/20/18
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