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• points. Monitoring point NF-3 was established in September of 1997 to monitor any mining- related impacts from the West Valley Fill. It should be noted that NF-3 is also downstream from [he Town of Somerset and monitoring results for this station may reflect impacts from domestic water use, leakage from sanitary sewers, and other factors. Colorado School of Mines was contacted to conduct an aquatic impairment study for the Sanbom Creek Mine requested by the Colorado Department of Health. The purpose of the study was to investigate possible impacts of the mine discharge on the aquatic habitats and organisms of the North Fork of the Gunnison River. On January 30, 1995 [he Colorado School of Mines, Division of Environmental Science and Engineering issued the final report "Aquatic Impairment Study of the Sanborn Creek Mine Discharge, Somerset, Colorado." A Copy of the report is included as section 6. The conclusions of [he study are that the Sanbom Creek Mine has a minimal effect on stream macroinvertebrates in general, that the discharge has little, if any, effect on the overall food base for fish, and that the use of the river for fishing has not been impaired. Somerset Mining Company agreed, and Oxbow Carbon Minerals, Inc. agrees with the conclusions of the report. Further, as a result of the report, additional "WET" testing following the report, and a record of compliance during routine testing, the CDPS discharge permit was amended. Monitoring frequency has been reduced, and the "WET" test is now required for fathead minnows only. Spring monitoring points SP-1 through SP-11 are designed to monitor the springs and correlate [he data with the prior monitoring data presented on pages 2.04-29vii through 2.04- • 29xvii of the permit document. One year prior [o retreat mining under Springs 1 through 6, monitoring will recommence and the data will be interpreted and correlated. A significant change in the quality or quantity of flow from [he springs after retreat mining would indicate that [he mine may be having an impact on the springs. Springs 1 through 6 are located above the mine workings and are separated from the mine by over 2,000 feet of overburden. The spring monitoring data, Springs 1 through 11, interpretation and correlation with pas[ monitoring was submitted with the 1992, 1993, and with the 1994 annual hydrologic reports. No mining will be performed within the angle of draw of Springs 1 through 6 or Springs 10 and 11 until the baseline monitoring and interpretation of the data is complete and approved by the Division. Baseline monitoring was completed in June 1994. Interpretation and correlation of the data was submitted [o the Division on September 15, 1994. The 1996 letter to OCM regarding the 1995 AHR states that the data are acceptable as submitted, and the OCM should continue on the approved monitoring plan. Springs 1-6 have continued [o be monitored after approval of the report by the Division. When [he present spring monitoring was begun in June 1993, effort was made to locate the springs as marked on the Monitoring Location Map from Western Slope Carbon Hawk's Nest Mine included in the permit documents as page 2.04-SOxviii. The legend indicates the marking to be Approximate Spring Location. Actual monitoring locations have been marked on the ground, and monitored at the same locations since. Spring 1 is a depression near a grove of aspen trees. The depression may have contained water when it was monitored previous to 1993. Data have not recorded a flow. The other field parameters, pH, conductivity, and temperature would indicate monitoring of surface water collected in the depression. 6