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manholes to stock tanks and the water will be used for stock watering. A float device, or other type of control, will
<br />be installed at the stock tank to control flows to the tank. The locations of the manholes were determined in the
<br />• field based on topography and stock water distribution needs. The segment of the line which traverses the former
<br />surface mine area required that available topsoil be salvaged, and then replaced on the trench excavation. For this
<br />segment, topsoil was salvaged and placed to one side of the trench and subsoil excavated and placed on other side
<br />of trench, the waterline was bedded and placed in the trench, the trench backfilled with subsoil, then topsoil was
<br />replaced over the footprint of trench, and the area was broadcast seeded with the approved seed mixture.
<br />In 2007, (MR07 -216) the Fish Creek Ventilation Shaft was converted to a dewatering well to replace the Fish Creek
<br />South Dewatering Well, where a defective dewatering pump became stuck down -hole in the well and could not be
<br />retrieved for repair or replacement. The original Fish Creek Dewatering System consisted of two adjacent dewatering
<br />installations. Each of the two 12.75 -inch O.D. Fish Creek North and South Wells house a 6 -inch discharge pipe,
<br />electrical cable, and a 300 -600 gpm capacity submersible pump. Electrical power is supplied by the distribution
<br />powerline depicted on Map 39, Foidel Creek Mine Powerline Location. The substation location for the dewatering
<br />wells is shown on Maps 26 and 39. At this location, after topsoil removal, a fence was constructed around the
<br />perimeter of the site, enclosing an area of approximately 48 x 24 feet. Within the fenced area, a 12 x 12 x 1.5 foot
<br />concrete pad was poured and a four -pole structure was constructed. The general layout of this site is shown on Figure
<br />18. A gravel blanket, approximately 6 inches deep, has been placed around the concrete pad and extends to the fence.
<br />During the life of the facility, weeds will be controlled within the fence using selective herbicides. As previously noted,
<br />the Fish Creek South Well has been replaced by the Fish Creek Ventilation Shaft Dewatering Well.
<br />Pumped mine water from the Fish Creek North Dewatering Borehole, and Fish Creek Ventilation Shaft Dewatering
<br />Well is transferred to either buried 8 -inch HDPE connector lines and a distribution point (to water treatment system), or
<br />to a 12 -inch pipeline which transfers water back to the Area 1 Pit Mine Water Storage Reservoir. At the distribution
<br />point, the flow is metered and regulated to discharge a desired quantity of water to the electro- coagulation system and
<br />treatment ponds, and to return any excess flow to the mine through a recirculation line that discharges into the Fish
<br />• Creek Ventilation Shaft Dewatering Well. The recirculation line allows the borehole pumps to run at rated capacity,
<br />while regulating discharge from the treatment ponds at a lower rate. The recirculation line is a 4 inch HDPE pipe,
<br />buried underneath the road on the east side of the east cell. The recirculation line ties into the mine water discharge line
<br />in a manhole placed in the north berm of the eastern cell. Also within the manhole are valves to direct flow to the
<br />recirculation line, and flow meters for monitoring the mine water discharge line and the recirculation line. When the
<br />line and manhole are no longer needed, they will be removed from the site as part of the final reclamation process.
<br />In the Spring of 2006, an electro - coagulation system replaced the existing sodium hydroxide (caustic) system for
<br />treatment of water pumped from the Western Mining District at the Fish Creek Borehole. Safety, maintenance, and
<br />cost benefits were the primary reasons for replacing the existing caustic treatment system. The electro - coagulation
<br />system applies a constant electrical charge to the incoming mine water, ionizing particulates in the water feed
<br />stream, and causing the charged particles to agglomerate (coagulate), and drop -out. The existing treatment ponds
<br />will still be used to capture the precipitates from the treatment process. The system is essentially a modular system,
<br />housed in two metal shipping containers; the equipment is housed in a 40 x 8 x 10 foot high container mounted on
<br />poured concrete piers; the other 25 x 25 x 24 foot container, containing the process tank, valves, and flow metering
<br />equipment sets on a 6 -inch thick monolithic concrete pad. The containers housing the system are located
<br />immediately east of the electrical control building. An 8 x 19 foot, 5,000 gallon water tank is installed in one
<br />corner of the second container. Power for the EC system is supplied from the adjacent substation. One powerpole
<br />was previously installed adjacent to the caustic building, an additional powerpole may be necessary, which can be
<br />used with one or more drop -lines to provide power to the EC buildings. Please refer to the attached Exhibit 49G
<br />drawings, depicting the layout of the proposed buildings and associated piping, as well as the supporting text for
<br />construction details. Map 24 (sheet 3 of 3) also shows the general EC facility location.
<br />A treated product line discharges from the EC water tank to the first settling pond, with the treated water routing
<br />• through the baffled 3 -cell treatment ponds to assure adequate retention time to allow settlement of the agglomerated
<br />solids prior to discharge. In order to handle both normal discharge and any potential overflow from the treatment
<br />settling ponds, a 200 -foot 12 -inch PVC pipe is attached to the discharge culvert from the third and final treatment
<br />TR09 -70 2.05 -50.1 11/16/09
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