Laserfiche WebLink
The pilot passive treatment system will be constructed at the toe of the lower mine bench (waste- <br />rock dump). This is the preferred location for the treatment system because of better access <br />during winter months. In addition, retort water from the mine's retort drainage pipeline can <br />easily be accessed as the drainage pipeline trends directly through this area (see Figure 2). <br />A diagram of the proposed passive pilot treatment system is shown in Figure 3. To manage spill <br />containment and control, the SRB cell will be constructed in an excavation lined with 30-mil <br />polyvinylchloride (PVC). If deemed necessary, bedding material may be used to protect liner <br />integrity. The lined excavation will incorporate a drainage system that conveys any spill water <br />back to the main retort-water drainage pipeline. Leak or spill drainage will be accomplished <br />using pipe-boots in the liner. Retort-water raw feed will be piped from the existing 6-inch <br />diameter steel pipeline to the SRB cell by way of schedule 40 PVC 1-inch pipe. All pipe fittings <br />will have water-tight connections (compression or other suitable fittings). A valve will be <br />installed in the main retort-water line to regulate flow into the 1-inch feed line. In addition, a <br />valve will be installed in the 1-inch feed line to more accurately regulate flow into the SRB cell. <br />The SRB cell will consist of a polyethylene tank measuring 140-inches long by 64-inches wide <br />by 64-inches high, a volume of approximately 2,500 gallons. The SRB cell will be set in the <br />lined excavation such that the top of the tank will be near or up to 1-foot above grade. The sides <br />of SRB cell will be backfilled to prevent freezing. The influent (raw retort-water) will enter into <br />the bottom of the tank and percolate upwards through bioreactor media. The bioreactor media <br />will include the following materials in the approximate percentages by weight: 10% manure, 10% <br />alfalfa or hay, 30% crushed (sand size) siliceous aggregate, and 50% wood chips and sawdust. <br />Certain enhancements may be made to facilitate flow and mitigate clogging or blockage of inflow <br />and outflow lines. <br />Outflow from the SRB cell will exit the tank flow by way of a 2-inch PVC pipe (Schedule 40) to <br />the main retort-water drainage Line. Sampling ports will be constructed to facilitate sampling of <br />influent and effluent. The retort-water drainage line will convey the water to the evaporation <br />pond with any other retort discharge that is not treated in the passive treatment system. <br />5.0 Monitoring and Sampling and Analysis <br />Monitoring of the passive pilot treatment system will be conducted to observe and adjust <br />optimum flow rates into the cells, sample and analyze for water chemistry, and prevent system <br />