Laserfiche WebLink
TRAPPER MINING INC. <br />January 9, 2015 <br />Mr. Jared Ebert <br />Environmental Protection Specialist <br />Colorado Division of Minerals and Geology <br />1313 Sherman Street, Room 215 <br />Denver, CO 80203 <br />Dear Mr. Ebert: <br />Re: Notification of effluent discharge exceedance <br />On December 9th, 2014 a routine monthly List A -1 sample was taken at each discharging NPDES <br />site on the mine site. At NPDES site 011 a resultant value of 97.0 mg /L was recorded for Total <br />Suspended Solids, (TSS). Per the NPDES permit for Trapper Mine, the TSS value may not <br />exceed 35 mg /L unless a precipitation event or snowmelt is occurring, in that situation TSS is <br />waived and the Settleable Solids standard of less the 0.5 mL /L /h is enforced. I requested that <br />ACZ Laboratories re -test this parameter to rule out any error. They reported a re -test value of <br />99.0 mg /L on January 5, 2015. The original value will be used to report on the DMR. <br />The reason for the high result is not entirely known. I did notice a slight turbidity to the water as <br />it was collected. The sample was taken just above the Parshall flume used to record flows at <br />NPDES 011. The pond system itself had minimal flow, the bulk of the flow at the flume was <br />from East Pyeatt Spring, a natural spring below the dam of East Pyeatt #3. The mine site and <br />region had received a moderate snowfall of nearly 4inches prior to Thanksgiving on the 24th of <br />November. Temperatures ranged from 30 to 56 for daytime highs during this period and lows in <br />the high 20's. The snow did persist for several days, but was mostly gone by the 9th, except at <br />higher elevations of the mine. <br />The colder weather also appeared to cease the growth of thick patches of water cress present in <br />the waterway at NPDES 011. Prior to the snow the plants were still mostly green and erect. <br />During sampling on the 91h I noticed the plants had collapsed into the water and turned brown. <br />Either of the above scenarios may have contributed to the high result either due to lagging <br />snowmelt, or detritus and debris from the thick vegetative die -off. An animal may have even <br />disturbed the water prior to sampling, again the exact reason is not known. There were no other <br />issues noted by myself on that day, or in your monthly inspection in the following days. No <br />industrial activities are known to have occurred above these ponds such as pit pumping and <br />nearly the entire watershed for NPDES 011 is reclaimed. <br />Observations of the discharge on January 6t' appeared clear, no discharge could be discerned <br />from the pond and was not therefore sampled. I will continue to monitor the site for any <br />irregularities. <br />P.O. Box 187 Craig, Colorado 81626 (970) 824 -4401 <br />