APPCOR12155 - Laserfiche WebLink

Home Browse Search

:" . i • Two intermittant, or perennial?). What was the basis for the projected avail- ability of 2 cfs from Hubbard Creek? Was Case No. W-3051 decided partly on the basis of available streamflow data for Hubbard Creek? Provide a statement concerning the availability of flow data for the small tributary entering Hubbard Creek from the northeast. If no data is avail- able, describe observed flow frequencies. Provide a statement concerning the prese_.nce or absence of wells or springs above the mine. If wells or springs do exist, they should be assessed as potential sources of usable water and as being subject to possible im- pacts from subsidence. See 783.15. Provide a copy of NPDES permit CO-0033533, reservoir storage permit, and water well permit. Provide a monitoring plan for the collection of surface and ground water quality and quantity data. Both Hubbard Creek and the alluvial well being used as a water supply should be monitored. Monitor- ing stations should be set up on Hubbard Creek just upstream and downstream of the disturbed area. Monitoring at these stations should be on a monthly basis or during Portions of the year when flow is intermittant, monitoring should be done during each runoff event. Parameters to be analyzed each time a sample is taken are: quantity, temperature, total and dissolved iron, total manganese, TSS, TDS, pH, acidity (alkalinity), Ca, Mg, Na, K, HCO CO SO and C1. Parameters to be sampled on a one time basis (or3more3if h4gh concentrations are found) are nitrate nitrogen, ortho- phosphate, and trace elements (i.e., Pb, Cd, As, Hg, Mo, Se, etc.) The alluvial well (W-3050) should be monitored quarterly for the same parameters listed above. Sediment Control ~. Provide a map showing the seven drainage areas described in the sediment pond calculations. Provide a readable copy of page 206 of the application. Clarify which of the four ponds (1, 2, 3, and 4) shown on Exhibit A cor- respond to the pond calculations (ponds 25A, North Sediment Pond, South Storm Water Pond, Pond 1, Pond 2) given in the application. ~_.Provide specific dewatering pipe and overflow weir designs for each of the four ponds. 3 Provide pond embankment cross-sections showing top widths, heights, slopes, locations of dewatering and overflow devices, locations of rip-rap, placement of fine and coarse materials, seepage barriers, cutoff trenches, etc. lr. Provide the results of any geotechnical investigations, construction ma- terials investigations, etc. done to provide data for design and con- struction requirements. This is especially pertinent to the 25 acre-foot pond. Provide a more detailed description of the inspection, maintenance and oper- ation procedures to be used for the 25 acre-foot pond. Describe (and show plans and locations for any diversions) how 2 cfs of flow is diverted from Hubbard Creek for use at the mine.