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(~ on site and passed through a settling pond. This pond has been sized to contain the 10-year, 24-hour storm with a spillway designed to handle any flows greater than that caused by such a storm (Appendix B). The pond also has the capacity to hold the sediment generated over a three-year period. The pond will be dewatered by evaporation and percolation, and anon-clogging dewatering device will be available. The entire site has been enclosed by a berm to prevent upstream flows From entering the site, as well as preventing site generated flow from leaving. The pond will be cleaned when sediment elevation reaches 7100.7. This '. • sediment will be placed within this disturbed area. In October of 1980, Northern requested a small area exemption for the topsoil stockpile and the equipment storage area. These two sites were downstream of the sediment pond.The sediment control method proposed for the sites was to constuct a ditch around the area and install 2" by 4" wood frames with wire mesh and filter fabric in the ditch. The minor revision was granted as MR-A. The topsoil stockpile has now been reclaimed and the pad site was left at the request of the landowner. In November of 1981, Northern requested a minor revision to expand the capacity of the sediment pond at the Northern 111 Mine to 1.9 acre-feet. This was done in order to improve efficiency and detent- ion time. The minor revision was granted as MR-C. In April of 1985, as reclamation was underway at the Northern 111 Mine complex, Northern requested a minor revision to remove the small sediment pond at the office-bathhouse site during reclam- ation. Northern stated that if the pond was left in after re- seeding, additional disturbance would be neccessary after seeding establishment, and that the small 2.3 acre area could be handled by heavy mulching and by placing a sediment fence in the spot now occupied by the dam. The revision was granted as MR-02. C~3.5