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Water Quality Standazds. Of course, the DMG does not set or enforce water quality standards. However, the DMG does require that as a condition of minimization of impacts to the hydrologic balance that operators meet all other Local, State, and Federal requirements. In that regazd, the criterion upon which the DMG must measure effluents generated within the mine permit boundary is surface and ground water quality standazds. Thus, until the CDPHE indicates otherwise, process waters that do not meet water quality standards must be controlled by the operator, either from forming or from dischazging." Dr. Posey's discussion is flawed in two respects. First in the selection of water-quality criteria upon which to judge the acceptability of runoff and second in the use of the term "process waters." CC&V assumes that Dr. Posey's position translates to a requirement to treat natural springs and associated ground water, as well as natural surface waters to meet "Table Value Standards" ("TVSs"). (TVSs aze obtained through site-specific application of the information contained in the Water Quality Commission's regulations §3.1.16(1). Dr. Posey appears to ignore ambient-based water-quality standards and the fact that Arequa Gulch is not classified. As one result, he has selected a set of Table Values Standards and applied them to a stream whose water quality is poorer than these arbitrary "Table Value Standazds." With experience in water quality regulations, one recognizes that one can not be held to controlling anon- point source discharge of water to standards that the receiving stream cannot meet. Water- quality standazds aze, of course, site-specific and TVSs aze not assigned everywhere if ambient water quality is poorer. We point out that under the Water Quality Commission's regulations, specifically at §3.1.7(1)(b)(ii), "Ambient Quality-Based Standards" are defined as follows: "For State surface waters where the natural or irreversible man-induced ambient water quality levels are higher than specific numeric levels contained in Tables I, II, and III, but are determined adequate to protect classified uses, the Commission may adopt site-specific chronic standards equal to the 85th percentile of the available representative data. Acute standards shall be based on table values or site-specific-criteria-based standards, and in no case may an ambient chronic standard be more lenient than the acute standard." Thus it is abundantly clear that in situations such as Arequa Gulch, ambient water quality standards, when standards are established (see below), are justified. Further, the Commission's regulations, at §3.1.6(1)(e), specify: "Classifications should be for the highest water quality attainable. Attainability is to be judged by whether or not the use classification can be attained in approximately twenty (20) years by any recognized control techniques that are environmentally, economically, and socially acceptable as 6