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C, j lrolo TRAPPER MI[IIA6INC. July 21, 2009 CERTIFIED RECEIVED JUL 2 9 2009 Division of Reclamation, Colorado Department of Public Health and Environment Mining and Safety WQCD-PE-B2 4300 Cherry Creek Dr. South Denver, CO 80222-1530 Subject: Second Quarter 2009 Colorado Wastewater Discharge Monitoring Reports Permit No. CO-0032115 To whom it may concern: Enclosed are Trapper Mine's Second Quarter 2009 Colorado Wastewater Discharge Monitoring Reports for the period 04/1/09-06/30/09. During this quarter, five NPDES outfalls were active. Outfalls 001, 002, 011 and 020 discharged throughout the quarter. Outfall 021 discharged during the beginning of April due to precipitation events in the form of snow and subsequent melting. Outfalls 005, 008, 009, 012, 013, 014, 015, 016, 017, 018, 019, 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. Also enclosed are monthly NOAA weather summaries for the reporting period and WET test report forms as applicable. Three outfalls were sampled for WET analyses during the quarter. Two species acute tests were completed at outfalls 011, 020 and 021. No exceedances of WET test limitations were observed at any tested outfalls. Primary effluent limitations were exceeded at three outfalls during the quarter. Two of these exceedances were in direct response to snowmelt and or precipitation events resulting from snowfall on the site. Due to the nature of melting snow, the runoff can vary considerably from one watershed to the next. Samples taken April 7, 2009 showed an exceedance of TSS at outfalls 020 and 021 due to winter snow pack melting and a wet snow storm the previous day. 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. A single exceedance of primary effluent limitations for pH occurred at outfall 001 during the quarter. A reading of 9.2 was recorded on June 90. The outfalls at Trapper mine are direct discharges from sediment control ponds on the site. Watersheds and individual pond systems vary considerably across the site encompassing nearly 30 ponds. Outfall 001 is located at the final pond of a series of five settling ponds. Each pond discharges to the next until discharging from the final pond at the NPDES sampling site. The ponds are very mature and have developed rich and diverse plant and animal communities. Aquatic vegetation has continued to increase in the system, including rich algal blooms, especially in summer. As natural systems, the vegetative communities are not altered by the operator. Nor have these ponds required cleaning of sediment in recent years due to the majority of this watershed being reclaimed. Vegetative growth and other microorganisms flourish in these ponds. There is a multitude of factors that contribute to pH levels in a pond. Not all factors can be controlled or fully understood in a pond setting such as this one. Historically, pH has risen in this system each summer. The typical treatment for high pH has been the addition of CO2 gas at the discharge point. When it was discovered that pH was slightly higher than the standard, COZ treatment was immediately initiated and the condition was corrected. Treatment is continuing at this outfall. A contributing factor this spring for higher pH may be above normal precipitation in late May and during the entire month of June. Dilution of the ponds natural calcium levels due to rainfall and mixing of the ponds temperature zones may have contributed to the P.O. Box 187 Craig, Colorado 81626 (970) 824-4401