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1` ~ • • Water Ouantitv and Oualitv (includes 1993 analvsis 1. Water levels and flow volumes were generally within established ranges during 1994. Presently subsidence impacts to undermined hydrologic features are not apparent. Two interesting observations are worthy of note regarding groundwater quality. First, well B07 near the east portals is completed in the Mancos Shale and until early 1993 had measured conductivity values in the range 100-300 umhos/cm. However, since that time, 13 measurements indicate a conductivity averaging near 1000 umhos/cm. Although it is indicated that the 1994 values were within the range previously established, they only fall within the previously established range due to a sudden and dramatic increase in conductivity occurring in 1993. The operator should attempt to explain this apparent mine related impact. Second, a noticeable and sudden drop in conductivity values since 1990 is noted in the East Roatcap Creek and Stevens gulch colluvial wells. Is Bowie Resources aware of any phenomena that may account for this noted change in EC? Subsidence Renort 1. The subsidence monitoring plan as approved in the permit may not meet the requirements of Rule 2.05.6(6)(c). Monuments are being surveyed semi-annually and reported annually rather than quarterly and semi-annually, respectively, as the Rules require. Furthermore, the operator is reporting to the Division each year which stations will be surveyed the following year. Clearly, by Rule, the Division needs to approve of any reduction of monitoring (Technical revision definition 1.04(136)). The operator should monitor quarterly, submit data semi-annually, and stick to a set monitoring site schedule until changed or modified by an approved technical revision. 2. The operator seems to have difficulty surveying the required stations with a reliable degree of accuracy. Three station survey discrepancies are explained by potential errors in surveying or changes in survey techniques. It is important that the operator collect and submit valid and accurate data. No conclusions or determinations of mining impact can be made using data which contains the magnitude of errors presented by this report. The Division recommends that an independent, professional surveyor be obtained by the mine to collect data which the Division can rely upon as baseline or at minimum compare to the existing data for accuracy. 3. In a related issue, stations 94, 96, 97, and 98 all show different data for the same date when compared to the data reported in 1993. These are important sites and no explanation or identification of these discrepancies is made by the operator. The operator should explain this occurrence