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<br /> <br /> <br /> <br /> 8 <br />The North Thompson Creek Mines filed for temporary cessation of operations on July 31, 1984 <br />and for permanent cessation status on August 15, 1986. <br /> <br />Reclamation of the mine and loadout facilities have involved two phases: an interim and a final <br />phase. The interim reclamation phase was ongoing and was designed to add to stability and <br />aesthetics during mining and to provide an opportunity for testing and improving revegetation <br />techniques. The specified goals of interim reclamation at the mine site were to stabilize slopes <br />and prevent erosion, improve wildlife habitat, and beautify the area. The interim plan at the <br />mine site included incremental seeding of the refuse area as the pile was constructed. The first <br />increment was seeded in 1979. <br /> <br />The goals of the interim reclamation plan for the loadout were to minimize visual impact and to <br />prevent the topsoil pile from becoming contaminated. Visual impact was minimized through <br />revegetation which involved the planting of native and exotic ornamental species. Revegetation <br />commenced in 1980 and was in a state of maintenance by 1982. Topsoil was protected from <br />possible sources of contamination by relocating the pile to a protected area. In 1981, the topsoil <br />stockpiles were reshaped, fertilized and planted to protect them against erosion and <br />contamination. Additional protective measures, including drainage control and dust suppression, <br />were used to protect stockpiles located near coal loading structures. <br /> <br />Final reclamation of the refuse area was completed in 1986. The reclamation included regrading <br />the top bench and covering the refuse with one foot of cover. Some of the soil used to cover the <br />refuse pile was imported, because topsoil was not saved during the early years of mine operation. <br /> <br />In 1987, the rest of the mine site was reclaimed. The surface facilities were removed and the <br />portals, shafts, exploration holes, and wells were sealed. On April 28, 1988, a discharge of iron- <br />laden water was discovered entering the creek. The discharge was traced back to the No. 1 Mine <br />portal seal and adjacent airshaft, which were leaking as a result of increased hydrostatic <br />pressures as the ground water was allowed to return to its equilibrium level following the <br />cessation of pumping. <br /> <br />The backfill in front of the No. 1 Mine portal seal was excavated to expose the seal and airshaft. <br />Two valved pipes were installed in the portal seal to control the seepage and route it to several <br />treatment ponds via a French drain. The seepage water entering the treatment ponds was treated <br />with sodium hydroxide in order to increase the pH and allow the iron to precipitate before the <br />water discharged to the creek. The treatment system was later modified to increase the residence <br />time of the seepage water in the treatment ponds. This was accomplished by elongating the <br />treatment ponds to increase their volume. The longer residence time resulted in the iron <br />precipitating out of the water, to below the NPDES effluent limits, without the sodium hydroxide <br />treatment. The chemical treatment was then discontinued. Currently, a three pond passive mine <br />water treatment system remains in operation in the Developed Water Resources Area on <br />approximately 4.1 acres of land near the portal of the No. 1 Mine. <br /> <br />The water rights for the water produced from the mine workings and subsequent treatment in the <br />Developed Water Resources area were previously obtained by the mine operator. Water <br />Division No. 5, Case No. W-2979 granted the No. 1 Mine a water right for 101 gpm with an