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. 4 v P.O. Box 187 April 3, 2017 TRAPPER MINING INC. Craig, Colorado 81626 Colorado Department of Public Health and Environment Water Quality Control Division WQCD-P-132 4300 Cherry Creek Dr. South Denver, CO 80246-1530 (970)824-4401 RECEPVEo RECr11.#1!0 APR 112017 APL? ; , 1017 DMSION OF RECLAMATION DMININO AND SAFE ;KN MINING AND SAFETY Subject: First Quarter 2017 Colorado Wastewater Discharge Monitoring Reports Permit No. CO -0032115 To Whom It May Concern: Enclosed are Trapper Mine's First Quarter 2017 Colorado Wastewater Discharge Monitoring Reports for the period 01/1/17-03/31/17. During this quarter, three NPDES outfalls were active. Outfalls 001, 002 and 011 discharged routinely throughout the quarter. Outfalls 008, 009, 017, 018, 019, 020, 021, 022, 023 and 024 did not discharge during the quarter. Values reported on the enclosed DMRs represent the maximum (or minimum as applicable) monthly/daily values generated at each outfall during the quarter. The TDS is reportable on a quarterly basis per our permit. The TDS values are as follows for each active outfall: 001 002 011 3660 mg/L 2480 mg/L 3640 mg/L Also enclosed are monthly NOAA weather summaries for the reporting period. The enclosed NOAA weather summary reports show the temperatures and precipitation measurements for the period monitored. Daily precipitation measurements are recorded at 7:00 a.m. as well as daily maximum and minimum temperatures from the previous 24 hours. Primary effluent limitations were exceeded at one outfall during the quarter. These exceedances were in direct response to snowmelt and or precipitation events resulting in snowfall on the site. Due to the nature of melting snow, the runoff can vary quite a bit from one watershed to the next. Samples taken March 7, 2017 showed an exceedance of TSS at outfall 011 due to winter snow pack melting. This exceedance followed a warm weekend after a significant snowstorm on February 28th brought over ten inches of snow to the site. The enclosed weather summaries show how the snow diminished quickly over the weekend as temperatures warmed, an additional two inches of snow fell the day prior to sampling and had melted some by the day of sampling. The attached photos show the site on the day of sampling, the fresh snow is evident in the photos. Lingering snowpack is evident at the higher elevations, as is some evidence of melting. The alternate limitations for Settleable Solids, applicable in the event of discharge caused by precipitation (or snowmelt) less than or equal to the 10 -year, 24-hour precipitation event, was met at all outfalls. No exceedances of primary effluent limitations for pH occurred during the quarter. Trapper is required to maintain sediment levels in ponds at or below 60% of the pond volume. All outfalls have been properly maintained and no ponds exceeded the 60% threshold for sediment accumulation.