5 Colo. Code Regs. § 1002-61.39
STATUTORY AUTHORITY
The provisions of 25-8-202(1)(d) and (1)(i) and (2); and 25-8-501 to 504 C.R.S. (1989 Repl. Vol. 11A and 1992 Supp.) provide the specific statutory authority for this amendment to the Colorado Regulations for State Discharge Permit System, adopted by the Commission. The Commission has also adopted, in compliance with 24-4-103(4) C.R.S. (1988 Repl. Vol. 10A and 1992 Supp.), the following statement of Basis and Purpose.
BASIS AND PURPOSE
As a result of this hearing, the Commission has:
Repeal and Recodification:
The following statement of basis and purpose was adopted in conjunction with the original adoption of regulation 3.10.0:
The subject regulations are for implementation of the "Water Quality Standards for Salinity" for the Colorado River. These standards were adopted by the Water Quality Control Commission on May 4, 1976 and set numeric criteria for salinity in the Colorado River as follows:
Below Hoover Dam - 723 mg/l
Below Parker Dam - 747 mg/l
Below Imperial Dam - 879 mg/l
The standards are required by the Federal Water Pollution Control Act, 33 U.S.C. Section 303, and the Colorado River Basin Salinity Control Act, 43 U.S.C. Section 1571.
The Plan of Implementation is comprised of a number of Federal and non-Federal projects and measures to maintain the flow-weighed average annual salinity in the Lower Colorado River at or below numeric criteria at the three stations as the Upper and Lower Basin states continue to develop their compact-apportioned waters. One of the components of the Plan consists of the placing of effluent limitations, through the National Pollutant Discharge Elimination System (NPDES) permit program, on industrial and municipal discharges.
The purpose of the regulation is to provide more detailed guidance to those municipal and industrial dischargers who wish to establish the non-feasibility of a no-salt-return to the Colorado River as is required by the adopted plan.
Since the standard of "No salt return where practicable," has already been adopted by the Commission, the scientific or technological issues involved in this regulation are limited to the type of technical data that must be submitted for the Department of Health, to determine the type of permit condition that will be included in each discharge permit.
Upon review, the Commission believes that it is more logical for these regulatory provisions to be a part of the overall state discharge permit regulations, rather than a free-standing regulation. This should make these regulatory provisions more accessible to those in the public, including the regulated community, who are likely to have occasion to be concerned with these issues.
Addition and Revisions:
The majority of the revisions to the regulation involve reformatting and editorial changes that make several terms used in the salinity regulation consistent with those used in the permit regulations. Other revisions include deletion of the "Purpose" section of the salinity regulation as well as the definition of "New Construction" which is now out of date. The major additions are the inclusion of two policies, for intercepted ground water and fish hatcheries, that were adopted by the Colorado River Basin Salinity Control Forum in 1982 and 1988, respectively. The Division has been informally using these policies, where applicable, to establish permit conditions.
The provisions for intercepted ground water can be applied to discharges from mines and construction dewatering activities and also allow infiltration of saline ground water into municipal wastewater collection systems to be taken into account. Their use allows for a much simpler application of criteria for determining permit conditions related to salinity which minimizes the burden on the permittee and the Division. The provisions that apply to fish hatcheries allow for a 100 mg/l increase in salinity through the facility in recognition of the fact that they are "flow through" systems and very little salinity is added. The Commission finds that it is appropriate to formally include these policies in the regulation.
5 CCR 1002-61.39