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r , Mayo and Associates to assist in evaluating the probable hydrologic consequences of the inflow and to analyze the chemical composition of the water and other data to determine its age and origin. We were able to determine from the temperature of the water from the fault (89° F) and from tritium and Stable Isotope Ratio analyses of the water, that the water is quite old (aged at approximately 36,000 years), and therefore, is not directly connected to surface water. The water is moderately alkaline, contains sodium bi-carbonate, calcium carbonate, and exhibits high conductivity and total dissolved solids concentrations (i.e. >4000 µmhos/cm conductivity and 2950 mg/L TDS). These values are higher than the parameters associated with the fault we encountered in the B East Mains on March 16, 1996, leading us to believe that we had encountered a different fault conduit, or "vertical reservoir". As you know we worked hard to manage the inflow water in such as way as to minimize its impact on the North Fork of the Gunnison River. From the beginning, the inflow water was pumped both to our sedimentation ponds, MB-1 (discharge point 002) and MB-2R (discharge point 004), outside the mine, and to the N W Panels sealed sump. In anticipation that we would soon begin to discharge some of the mine inflow water either via the sedimentation ponds or dvectly to the river (upon approval of the WQCD), we began collecting water samples from above and below our discharge points to establish baseline water quality data. To supplement this data, we also had Wright Water Engineers conduct a biological assessment of the river before (and then after) discharging to the river. The assessment showed that there was no impact to the river. We were initially able to manage the inflow water that was pumped out of the mine by containing it within the two sedimentation ponds to allow the suspended solids as much time as possible to settle out. From January 20 until the aftemoon of January 24, we were able to store the inflow water and consequently achieve some reduction in suspended solids content. Late in the aftemoon of January 24, we began discharging through pond MB-2R. We continued [o discharge through MB-2R until some time Tuesday morning, January 28. Pond MB-1 was held until Sunday January 26 when it was also discharged until January 28. Based upon the analyses of "pre-discharge samples (that MCC routinely takes prior to discharging any pond) of the water to be discharged during this time period, we were out of compliance with respect to our TSS effluent limit for only a short period of time. The WQCD was contacted daily (as was CDMG) and kept apprised of the discharges, including the suspected non- compliance discharges. Tom Anderson of Oxbow Carbon and Minerals, who operate the water intake system for [he Town of Somerset, was also contacted to ensure [hat their water system was not impacted. We also maintained communication with a local environmental organization (WSERC) that later published an article about the inflow in their newsletter (see attached). On January 29, MCC began to directly discharge inflow water to the North Fork of the Gunnison River after receiving authorization to do so from WQCD. To ensure that the water being directly discharged was within our NPDES effluent limits for our sedimentation ponds, MCC began monitoring the Flow rates and chemistry of the discharged water and conducted Whole EfFluent Toxicity (WET) testing on both the discharged water and river water. The water quality analyses of the direct discharges to the river from January 29, 1997 to February 7, 1997 when we stopped directly discharging mine inflow water into the river, demonstrate that no NPDES parameters, including WET tests, were exceeded during that time. Details concerning the discharge of water to the surface and to [he river, as well as the results of our water quality analyses, were provided to Ms. Kathleen Sullivan of the WQCD and to you in a lever dated February 19, 1997. From the beginning of the inflow on January 20, 1997 through March 5, 1997, approximately 84 million gallons (258 acre-feet) of water have been pumped from the fault inflow. Of this amount, approximately 50.4 million gallons (I55 acre-feet) were pumped outside and 33.6 million gallons (103 acre-feet) were pumped to the Northwest Panels sealed sump. The dvect discharge to the North Fork of the Gunnison River accounts for 36 acre-feet and the remaining 119 acre-feet were passed through the sediment ponds MB-1 and MB-2R for "batch treating" prior to discharge into the North Fork of the Gunnison River. Since mid-March, the inflow has continued at I50 to 200 gpm. In the mean time, the B East Mains fault inflow has remained generally the same since August 1996, even after encountering this new fault inflow in the Ist Southeast Headgate. The inflow is approximately 80 gpm and the temperature is 84° F. This flow has been emanating from [he floor of Entry No. 2 near cross-cut No. 21, with the appearance of a perpetual puddle. In early January, a gravel drain was constmcted across this entry (and our main travelway) to intercept the flow and direct it to a "clean" water pipeline in [he mine. We plan to combine these