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'000, <br />I/` <br />OXBOW MINING, LLC <br />3737 Hwy 133 P.O. Box 535 Somerset, Colorado 81434 USA Tel (970)929 -5122 Fax <br />(970)929 -5177 <br />October 3 2013 R'E�OVED <br />Octo , <br />OCl 0 � 2013 <br />Ms. Tapia Watson <br />Colorado Department of Health, WQCD p�VISION OF 77,C L*AATION <br />Permits and Enforcement Section MINING AN:) SAFETY <br />WQCD -PE -B2 <br />4300 Cherry Creek Drive South <br />Denver, CO 80246 -1530 <br />Re: CDPS Permit No. COG850064, July - September, 2013 Discharge Monitoring Reports, <br />Oxbow Mining, LLC., Elk Creek Mine. <br />Dear Ms. Watson: <br />Enclosed is the quarterly June - September, 2013 Discharge Monitoring Report (DMR) for the <br />Oxbow Mining, LLC., Elk Creek Mine Permit COG850064. <br />The enclosed DMR indicate only one issue relative to the routine non -WET testing parameters. <br />The alternative Outfall 015B showed a 30 day average (June) Total Recoverable Iron <br />concentration of 1,410 ug/1 vs. a limit of 1,000 ug /l. The Division should recall that Outfall 015B <br />is an alternate discharge location for the original 015A Outfall location found in Permit <br />C00000132 where the limit is 3,000 ug/1 for the 30 -day Average and 6,000 ug/1 for the Daily <br />Maximum. We believe the TR Iron limit in COG850064 is in error and should be similar to the <br />original Outfall 015A location. <br />As expected, due to high levels of alkalinity, the Chronic WET test of the test species <br />Ceriodaphnia dubia failed at the 100% effluent level. The % survival of the C. dubia at the 50% <br />dilution level was 100 %. Please see our previous DMR report correspondence to the Division <br />dated August 8, 2013 for the details regarding the Wet Test. <br />Pumping Update <br />The Division is aware that the pumping of the mine workings from the alternate Outfall 015B <br />location was made necessary to recover the mine after an unforeseen event where the mine had <br />to be sealed due to elevated carbon monoxide levels indicating spontaneous combustion in a <br />mined out section of the mine. Oxbow had been pumping water from the Mine at Outfall 015B <br />since June 3, 2013. On September 9, 2013 the Outfall 015B pumps were shut down. Oxbow re- <br />entered the mine, and established mine ventilation. Later the spontaneous combustion in the <br />mine re- ignited and the mine had to be re- sealed. Oxbow has now determined that the longwall <br />can not be recovered safely and that portion of the mine will be permanently sealed. Oxbow is <br />• Page 1 <br />