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SPECIFIC COMMENTS. <br /> DOCUMENT TITLE: CMLRB Permit Application <br /> 1. The upper aquifer occurs in the basal Uinta Formation and in the upper part of the underlying <br /> Green River Formation, above the A-Groove marker. The application refers to the federal <br /> definition of an underground source of drinking water (USDW) in 40 CFR Part 144.3 and <br /> concludes that the only USDW in the project area is in the upper part of the upper Aquifer in <br /> the Uinta Formation (p. G-8). This conclusion relies in part on a TDS-conductivity <br /> relationship but evidence for this relationship was not supplied with the application materials. <br /> The evidence was also based on a qualitative assessment of actual TDS values for samples <br /> where TDS and conductivity did not agree due to analytical error. However, there are not <br /> enough data in the application to define changes in water quality, stratigraphically, with such <br /> precision that all of the upper Green River can be excluded as a USDW, or for that matter <br /> that all of the lower Uinta can be included as a USDW. <br /> The operator should provide more information on groundwater quality. There should be <br /> enough information to characterize the relationship between TDS and conductivity, and if <br /> conductivity is to be used to interpret TDS, and hence the stratigraphic limits of the USDW, <br /> then the conductivity logs should be part of the permit application. The operator reliance on <br /> qualitative judgements about TDS should be shored up with more quantitative measures. <br /> 2. Page D-13 forward. Although the mining plan appears to presume that the solution cavities <br /> will be mostly symmetrical around the solution well pipe in the Saline Formation, it is likely <br /> that fractures, faults, other lateral discontinuities, and inhomogeneities in some strata of the <br /> Saline Formation will lead to production of solution cavities that are laterally asymmetrical. <br /> Lithologic variations it is acknowledged will promote greater dissolution and calving in some <br /> zones than in others. Thus, the shape of the solution cavity cannot be determined from <br /> product volume alone, and hence the maximum lateral extent of each cavity cannot be <br /> determined from product volume. The operator should demonstrate what steps may be taken <br /> to preclude intraformational contact between solution cavities. <br /> 3. Page G-3 and forward. The text on page G-3 indicates that the lower aquifer has a variable <br /> TDS and metals content. The text on page G-4 however indicates that the lower aquifer <br /> "does not meet the standard for drinking water because of marginal pH and high <br /> concentrations of various elements. While it might be protective of the company's interests <br /> to identify what portions of the lower aquifer are potable and what portions are not, both in <br /> the vertical and aerial sense, we would ask that the mining and groundwater monitoring and <br /> compliance plans instead address how the potable portions will be protected. Please indicate <br /> what protective measures will be taken to prevent contamination, and how non-compliant <br /> monitoring results will be addressed. <br /> 4. Page D-6; section D.2.4.1. The text indicates that some evaporation will take place at the <br /> Piceance site prior to placement of process waters in the pipeline to the Parachute facility. <br /> Presumably, this will take place in the Piceance Site Pond. The DMG needs to know more <br /> about the Piceance Site Pond. What is its function? What types of fluids and solutes will it <br /> 3 <br />