5 Colo. Code Regs. § 1002-37.19
The provisions of C.R.S. 25-8-202 (1)(a), (b) and (2); 25-8-203; 25-8-204; and 25-8-402; provide the specific statutory authority for adoption of these regulatory amendments. The Commission also adopted in compliance with 24-4-103(4) C.R.S. the following statement of basis and purpose.
BASIS AND PURPOSE
The Water Quality Control Commission completed a thorough review of Regulation No. 37 in July 2001, coincident with Regulation Nos. 34 and 35. To balance the workload and provide continuity with the upper basin, the Lower Colorado basin was moved to the cycle with the Upper Colorado basin (Regulation No. 33). This hearing addressed issues that had arisen since the 2001 hearing.
Some renumbering and/or creation of new segments was made in the basin due to information which showed that:
Lower Yampa segment 22
Lower Yampa segment 22a
Lower Yampa segment 22b
White River segment 9
White River segment 9a
White River segment 9c
White River segment 10a
Lower Colorado segment 4a
Lower Colorado segment 4b
Lower Colorado segment 9a
Lower Colorado segment 9b
Lower Colorado segment 13a
Lower Colorado segment 13b
Lower Colorado segment 19
In a continuation of the Commission's efforts to comply with the requirements contained in the federal Clean Water Act that all waters of the nation should be suitable for recreation in and on the water (known as the "swimmable" goal), the Commission reviewed several Recreation Class 2 segments. In Colorado, the "swimmable" goal translates into Recreation Class la, with the 200/100 ml fecal coliform and 126/100 ml E. Coli standard, and Class lb with the 325/100 ml fecal coliform and 205/100 ml E. coli standard. Class la indicates waters where primary contact uses have been documented or are presumed to be present. Class 1 b indicates waters where no use attainability analysis has been performed demonstrating that a recreation class 2 classification is appropriate, but where a reasonable level of inquiry has failed to identify any existing class 1 use. To maintain the existing Recreation Class 2 with the 2000/100 ml fecal coliform and 630/100 ml E. coli. standard on a segment, it must be shown that there is not reasonable potential for Recreation Class 1 uses to occur within the next 20-year period (e.g.: ephemeral or small streams that have Insufficient depth to support any type of Recreation Class 1 use or very restricted access).
A recreation class la classification of a segment is not intended to imply that the owner or operator of property surrounding a waterbody in a segment would allow access for primary contact recreation. The application of recreation classifications to state waters pursuant to these provisions does not create any rights of access on or across private property for the purposes of recreation in or on such waters. A recreation class 1 a classification is intended to only affect the use classification and water quality standards of a segment, and does not imply public or recreational access to waters with restricted access within a segment.
For segments changing to recreation Class la because no information was available about actual recreational uses, the last paragraph of section 31.6 will apply to future changes to the recreation classification where a proper showing is made through a use attainability analysis that a recreation Class 2 classification is appropriate, without application of the other downgrading criteria in this section. Moreover, the Commission is relying in part on the testimony from EPA that completion of a use attainability analysis showing that a lower recreation classification is appropriate satisfies applicable downgrading criteria. Based on these factors, the Commission intends that in a future rulemaking hearing, the test for adopting a recreation Class 2 classification would be the same as if it had been considered in this hearing
Based on the information received that showed Recreation Class 1 a uses are in place or are presumed to be present in at least a portion of the segment, the Commission changed the following segment from Class 2 to Class 1 a with a 200/100 ml fecal coliform and 126/100 ml E. coli standard on a seasonal basis:
White River segment 9b from 6/1 to 8/31
Based on the information received that showed Recreation Class la uses are in place or are presumed to be present in at least a portion of the segment, the Commission designated the following segments Class la with a 200/100 ml fecal coliform and 126/100 ml E. coli standard:
White River segment 10a
Lower Colorado segment 4b
Lower Colorado segment 9b
Lower Colorado segment 19
Lower Yampa 22b
Based on evidence presented, the Commission changed the following from Recreation Class 2 classification to Recreation Class 1b with a 325/100 ml fecal coliform and 205/100 ml E. coli standard:
Lower Colorado segment 6
The following segments retained their Recreation Class 2 classification with 2,000/100mL fecal coliform and 630/100 ml E. coli standard after sufficient evidence was received that a Recreation Class 1 a or 1 b use was unattainable.
Lower Yampa segment 21
Lower Yampa segment 22a
Lower Colorado segment 4a
White River segment 9a
White River segment 9b from 9/1 to 5/31
The Commission adopted a temporary modification for selenium of existing quality and a goal qualifier of TVS for Johnson Gulch from the confluence of Johnson Gulch and Pyeatt Gulch to the confluence with the Yampa River based on uncertainty.
Johnson Gulch is one of sixteen gulches included in Segment 3b of the lower Yampa River. This temporary modification was adopted pursuant to Regulation 31.7(3)(a)(iii) and data collected in the lower portion of Johnson Gulch near the Yampa River which showed selenium standards higher than aquatic life TVS. The Commission made no changes to the agriculture based selenium standard of 50 µg/l that was previously adopted in Segment 3b for upper Johnson Gulch, Pyeatt Gulch or any of the other fourteen gulches included in Segment 3b.
Water supply standards were modified at the July 2001 hearing to conform to the changes made by the Commission in the 2000 revisions to the Basic Standards (see Regulation No. 31 at 31.11 (6)). The Commission modified the water supply standards for iron, manganese, and sulfate that are based on secondary drinking water standards (based on esthetics as opposed to human-health risks). The numeric values in the tables were changed to Fe(ch) = WS (dis), Mn(ch) = WS (dis), and SO4 = WS. These abbreviations mean that for all surface waters with an actual water supply use, the less restrictive of the following two options shall apply as numerical standards, as discussed in the Basic Standards and Methodologies at 31.11 (6): either (i) existing quality as of January 1 2000; or (ii) Iron = 300 µg/L (dissolved); Manganese = 50 µg/L (dissolved); Sulfate = 250 mg/L (dissolved). For all surface waters with a "Water Supply" classification that are not in actual use as a water supply, no water supply standards are applied for iron, manganese or sulfate, unless the Commission determined as the result of a site-specific rulemaking hearing that such standards are appropriate.
White River segment 21
The Commission also clarified several segment descriptions.
PARTIES/MAILING LIST TO THE JULY, 2003 RULEMAKING HEARING.
5 CCR 1002-37.19