5 Colo. Code Regs. § 1002-32.30
The provisions of sections 25-8-202(1)(b) and (2); 25-8-204; and 25-8-402, C.R.S., provide the specific statutory authority for adoption of the attached regulatory amendments. The Commission also adopted, in compliance with section 24-4-103(4), C.R.S., the following statement of basis and purpose.
BASIS AND PURPOSE
The Commission established site-specific metals standards for Arequa Gulch in 1998. At that time Cripple Creek and Victor Gold Mining Company also requested that the Commission adopt a site-specific standard for pH of 5.5 - 9.0. The Commission instead adopted a temporary modification of 5.5 - 9.0 and asked that "additional and appropriate studies be performed by CC&V to evaluate CC&V's claim that the 5.5 pH level is protective of aquatic life in Arequa Gulch." Since the 1998 hearing, CC&V performed additional biological studies and a Whole Effluent Toxicity study. CC&V submitted the study results to the Division and to the parties to this hearing. The parties and the Division agreed to postpone the Commission hearing on this matter to the Arkansas River Basin triennial rulemaking hearing scheduled for November 12, 2001. In order to accommodate these objectives, the Commission extended the temporary modification to June 30, 2002 in order to give the Division, the parties, and CC&V additional time to evaluate the study results; give EPA additional time to consult with its Office of Research and Development; identify additional studies, if necessary; and implement such studies.
PARTIES TO THE RULEMAKING HEARING
5 CCR 1002-32.30