5 Colo. Code Regs. § 1002-32.12
The provisions of 25-8-202(1)(a)(b) and (2); and 25-8-204 C.R.S. provide the specific statutory authority for adding the numeric standards that were proposed.
The Commission also adopted in compliance with 24-4-103(4) C.R.S. the following statements of basis and purpose and fiscal impact.
BASIS AND PURPOSE - ARKANSAS:
The basis and purpose for the changes by segment is given below:
Segment 1, Upper Arkansas River - Two wilderness areas, Mt. Massive and Collegiate Peaks, were designated after the 1980 hearings. Creation of a new segment with High Quality - Class 2 designation will protect these areas and is consistent with Commission actions in other basins.
Segment 2b, Upper Arkansas River - Present description does not define the segment because of a typographical error. New description will define the segment.
Segment 3, Upper Arkansas River - Typographical error in cadmium standard. Change to 0.001 mg/l reflects the adopted standard.
Segment 25, Upper Arkansas River - Cottonwood Creek has been identified by the Colorado Division of Wildlife as habitat of the greenback cutthroat trout which is a State threatened and Federally endangered species. Creation of a new segment with High Quality - Class 2 designation will provide protection to the creek and is consistent with Commission actions in other basins.
Segment 4, Middle Arkansas River - Present description does not except Segment 24, should the
Commission decide to create a new Segment 24. The change will be needed if Segment 24 is adopted.
Segment 15, Middle Arkansas River - Typographical error for zinc standard. Original testimony showed the ambient level of zinc to be 0.2 mg/l in this segment. Change will reflect the standard as adopted by the Commission in 1981.
Segment 24, Middle Arkansas River - The waters are the only known habitat in Colorado for the Southern Red Belly Dace, according to the Colorado Division of Wildlife. Creation of this new segment with a High Quality - Class 2 designation should protect this species.
Segment 2, Fountain Creek - Drinking water standard is for total cyanide. The change in cyanide description from free to total will reflect what is required to protect the domestic water supply use.
Segment 9, Lower Arkansas River - The standards reflect a classification of Cold Water Aquatic Life -
Class 1 for waters that are Warm water Aquatic Life - Class 1 habitat. The change will reflect the Commission's intent in adopting the classifications and standards for this segment.
Segment 10, Lower Arkansas River - The standard for dissolved oxygen (D.O.), unionized ammonia (NH3) and nitrite (NO2) are table numbers for a Cold Water Aquatic Life - Class 1 designation. The change in the standards will reflect the Commission's intent in adapting the standards in 1981 and will provide protection to the Warm Water Aquatic Life residents to the waters.
FISCAL IMPACT STATEMENT - ARKANSAS RIVER BASIN
These regulations more accurately reflect the protections necessary for wilderness areas and rare and endangered species. In some cases, the only known habitat for certain species is identified. It is not anticipated that these changes will impact dischargers, except as a future development potential, yet will afford the benefit of protection of beneficial uses. In view of these facts, the Commission expects these regulations to be economically reasonable.
ADOPTED: December 6, 1985
5 CCR 1002-32.12