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Water Quantity and Quality (includes 1993 analysis 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 the operator indicates 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. What phenomena accounts for this noted change in EC? Subsidence Report 1. Once again, as previously stated in past reviews, I do not agree with the subsidence monitoring plan as approved in the permit nor do I believe that it meets 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. When a review is conducted in August, and the Division may not agree with the reduction in subsidence monitoring posed by the operator, one can see that it is a little late to speak up since 7 months of the monitoring year have passed. Clearly, by Rule, the Division needs to approve of any reduction of monitoring (Technical revision definition 1.04(136)). Simply stated, 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 unable to survey 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 absolutely essential, not to mention required by the Rules, 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. You may want to speak to Jim Pendleton about "second order" surveys and the accuracy which we require. I would recommend 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