Laserfiche WebLink
Peab o <br />Twentymile Coal Company U11 3 2009 <br />29515 Routt County Road #27 ? <br />Oak Creek, CO 80467 `??,atY1at10n, <br />970.879.3800 U;ve? <br />MinEng and Safety <br />July 28, 2009 <br />Ms. Tania Watson <br />Colorado Department of Public Health and Environment <br />Water Quality Control Division - Permits and Enforcement <br />4300 Cherry Creek Drive South <br />Denver, CO 80222-1530 <br />RE: PERMIT COG-850000. FACILITY NUMBER COG-850048 SECOND QUARTER 2009 DMR <br />SUBMITTAL <br />Dear Ms. Watson: <br />Please find attached the above referenced discharge monitoring report for the period April 1, <br />2009 through June 30, 2009, for Outfall 001A/001W (both site 10RT). Please forward to the <br />appropriate person. This is temporary emergency discharge permit. The discharge source is <br />groundwater, which is pumped from a portion our underground mine to prevent flooding. <br />Outfall 001A/001W discharged the first, third and fourth week of April. The pump experienced <br />problems in early May and was restarted briefly in mid-May allowing only one sample to be <br />collected. There has been no further discharge at this site to date. See further discussion below. <br />WET testing for 001W indicated that the effluent was not acutely toxic to Cerodaphnia. Laboratory <br />results are attached. <br />An exceedance was noted for the daily max of TSS (74 mg/L vs. the permit limit of 70 mg/L) in <br />April. Note that the 30 day TSS average in April was 35 mg/L, and the first sample collected in <br />May had a TSS of 10 mg/L. The elevated result may be from early snow melt entering the <br />discharge area. Twentymile Coal Company (TCC) will continue to monitor this parameter. <br />An exceedance was also noted for the 30 day average of total recoverable iron (1035 ug/L vs. the <br />permit limit of 1000 ug/L) in April. Note that analytical results for the one sample collected in May, <br />was 320 ug/L). <br />As a result of historic exceedances at this site, TCC has elected to discontinue all discharge until <br />we can evaluate the construction of a treatment pond with aeration as an initial phase for <br />treatment for Outfall 001A/001 W. TCC has received proposals for water treatment from multiple <br />consultants. Initial proposals are now under consideration.