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There is not an aluminum standazd applied to either Segment 21 or 22. Dr. Posey presumed a chronic silver standazd which is not the practice of the EPA nor, currently, the State. It must be noted that "process water" is not the appropriate term, in CC&V's view, to use to describe runoff from excess overburden or "waste" rock in view of the fact that the material has not, in the common sense of the term, been "processed." As is also explained in the section of this letter addressing reclamation and the lack of relationship of the deposition of excess overburden to RCRA-controlled management of wastes, the materials under discussion here aze not part of a process, rather they aze mineral beneficiation wastes. As Dr. Posey's associates who deal with inactive mine sites are awaze, these types of drainage aze normally referred to as "nonpoint" sources and dischazges. Controls to Protect Ground and Surface Water. The last phrase of Dr. Posey's second paragraph states that "process waters that do not meet water quality standards must be controlled by the operator, either from forming or dischazging." CC&V has proposed to control the formation of acid and subsequent leaching of metals through selective handling and placement of the overburden. The rock with higher concentrations of sulfur (pyrite) will, in lazge-part, be moved to existing mines (the Ironclad and Globe Hill Pits) and thus runoff will be eliminated. Surface azeas of these materials, as well as the rest of the overburden, will be graded, covered with suitable plant growth material, and planted with native and adapted vegetation. This cover will reduce both infiltration and entrance of oxygen into the overburden piles. These controls have been assessed as effective in controlling acid generation and subsequent leaching of metals in other situations. Dr. Posey, after summarizing CC&V's conclusions, critiques CC&V's proposal as follows (page 2 of his memorandum): "There is no proposal to protect surface or ground water from contamination, even though the leach tests indicate that the waste rock ("overburden") has the potential to generate acid and metals in concentrations exceeding water quality standazds. Thus the proposal outlined above cannot meet the requirements of the Amendment 6 Commitments to which it is meant to apply." The Amendment No. 6 commitment to which Dr. Posey refers is, we believe, that which states: "37. CC&V will provide the results of the long-term metals leaching and acid generation tests developed in concert with the OMLR (see Volumes VII and VIII of this Application) before any of the material from the additional test azea is loaded on the leach pad or placed in the waste rock storage azea. The Cazlton tailings must be tested for cyanide, metals leaching and acid generation prior to material disturbance. A report delineating the test results of the long-term leaching and acid will be submitted to the Office within ten working 13