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statement that "Ditches will be constructed to take enough of the runoff from disturbed areas into the pit to comply with this section" is not adequate. g) Calculations of expected runoff and sediment storage must be shown separate- ly for each sediment pond. The drainage area of each pond must be shown on the map(s). h) The diversion ditch mentioned for years 1 and 2 must be shown on the maps. We will also need to know the size of this ditch. Will the ditch remain throughout the life of the mine? i) Runoff from the office/shop complex will also need to be diverted to the sediment ponds. j) Table 4 shows the total disturbed acreage decreasing each year, after year four. Presumably, what you have done is subtracted [hose areas which have been seeded. However, federal regulations (715.17a) require that drainage from revegetated areas shall continue to pass through sediment ponds until the vegetation requirements have been met. For this reason, acreage should not be dropped from the "disturbed" category for the purpose of calculating sediment pond volume. k) Runoff from Mann Draw and the small triangular area north of Mann Draw will still need to pass through a sediment pond even after the area has been back- filled and graded. Again, section 715.17(a) applies. 1) There are several areas which will probably need to be ditched in order to insure that runoff from these areas will be contained by the sediment ponds. This will be reviewed in greater detail in the near future. m) Please provide calculations to demonstrate that culverts on the access road (particularly in Mann Draw) have been sized td handle the peak runoff from a 10 year 24 hour event. n) These points constitute only a preliminary review of your proposed sediment control system. 07~ce the additional information requested in this letter has been~eviewed in depth by the hydrologist on our staff. S.:b,nif/ed, Your Bolan w;ll ~e VI. Wildlife a) The wildlife species list provided is not site specific, and hence is unac- ceptable. Please provide information specific to the Bourg property. b) The staff is pleased with the interest which Flatiron Paving Co. has shown in finding ways to reduce the impact of the mine on the sage grouse strutting ground located north of the permft area. As we learn more about these birds, the staff may have some additional suggestions, which we will pass along to you. c) During the spring months, it is important that Flatiron prevent employees, dogs, vehicles, etc. from entering the strutting ground. This type of distur- bance could be far more detrimental to the birds than the more distant noise of the mine. d) At what time of the year does the applicant intend [o fertilize the sage- brush? This obviously should not be done during the dancing season. Please provide documentation that the Colorado Division of Wildlife and the BLM have approved this. e) Information obtained during the yearly monitoring of the strutting ground should be submitted to this office, as a part of the annual report. VII. Soils a) Additional baseline soils information must be provided. This is (6)