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Doc Date:12/11/2001 <br />I ~ / 899 --- <br />!' ~/ <br />• SECTION 3.0 Drainages Reconstruction, Improvement and <br />Repairs at Trapper Mine in 1993. <br />3.1 Drainage reconstruction 1987-93 <br />At Trapper Mine, all or portions of five major drainageways (Coyote, Johnson, E. Buzzard, E. No-Name <br />and W. No-Name) and their tributaries have been regraded and appropriately treated to reduce the erosion <br />rate and assist in permanent channel stabilization from 1987, through 1993. At the conclusion of the <br />1993 field season, approximately 50,450 linear feet (9.55 miles) of permanent drainages reconstruction <br />had been completed at Trapper Mine (see attached "Drainage Reconstruction" map). Drainage reconstruc- <br />tion totaling 3,000 linear feet was successfully completed in Johnson and West No Name drainages in <br />1993. For a complete discussion of Trapper's erosion control procedures and past monitoring results, refer <br />to Section 3.0 of TR-63, 1992 Annual Report. <br />3.2 Drainage Improvements and Repairs <br />Drainages improvements and repairs were performed to provide benefits to all drainages treated in 1987- <br />93, as well as portions of undisturbed drainage segments. Drainage improvements included dozer basin <br />construction in newly stripped topsoil areas and on regraded spoils. Drainage repairs and enhancement <br />were conducted in all previous reconstructed drainageways (87-92). Essentially no downcutting in <br />drainage bottoms occurred. <br />• Rock structures were installed at an average frequency of 100' throughout the reconstructed Johnson <br />Gulch and West No Name drainages in 1993. <br />3.3 Reconstructed Drainages Profiles (As-Built) <br />As agreed with the Division in Trapper's 1989 Annual Report (D.A. Berry Corres 6/8/90) Trapper is no <br />longer required to provide as-built drainage profiles as part of the annual report. <br />3.4 Coyote Gulch Monthly Peak Flows <br />There was no recordable discharge in Coyote Drainage during 1993 (Table 1). Excellent establishment of <br />vegetation on reclamation upstream of the flume as well as effective erosion control structures have com- <br />bined to create a hydrologically stable watershed. <br />FVL(6 3/94 <br />IDMG\93REPT31 <br />• <br />