2020-12-21_PERMIT FILE - C1981010A (7)

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Annually, by March 15 of each year, Trapper will provide the Division a brief report, the Annual Reclamation Report, with an as -built postmine contour map showing the approximate postmine position of drainageways. However, the best resolution which may be obtained is a 10 -foot contour interval, and so the location shown on the annual map will be only accurate to +50 feet laterally. The report will also describe where drainageway sections have failed, and what actions were taken to repair the failed section. The points of failure will be shown on the annual postmine contour map. Failure will be defined as the loss of the erosion control treatment and excessive channel cutting. Appendix W will be updated to contain each year's report and map. Additionally, in the Annual Reclamation Report a summary of as -built parameters for reconstructed drainages will be included in Section 3.0. A table will summarize the watershed acreage, curve numbers and slopes utilized in the design of the drainage section(s) completed each year. Map 1 of the Annual Reclamation Report will indicate which sections of the drainage were constructed that year. A diagram in Section 3.0 will demonstrate the watershed areas included and the curve numbers applied to them. This information will satisfy the as -built design requirements of reconstructed drainages by demonstrating the parameters used to determine the required storage capacity of structures needed per the stabilization design model detailed in section 4.8.1.3 and Appendix Q, Section 37. Also, in order to estimate the impact of runoff events on reestablishing drainage treatments, Trapper will provide the Division measurable peak flows from Coyote drainage as part of the annual report (see Appendix W). Data will be provided from April 1 through September 30 of each year, starting in 1988 and ending in 1991. 4-1830 Revision: /W _G 7 Approved: app 012015