5 Colo. Code Regs. § 1002-93.16
The provisions of C.R.S. 25-8-202(1)(a), (b) and (i), (2) and (6); 25-8-203; 25-8-204; and 25-8-401; 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
This regulation updates Colorado's List of Water-Quality-Limited Segments Requiring Total Maximum Daily Loads (TMDLs) to reflect additional water quality information available since the Regulation was last updated. This change was prepared to fulfill section 303(d) of the federal Clean Water Act (Act) which requires that states submit to the U.S. Environmental Protection Agency (EPA) a list of those waters for which technology-based effluent limitations and other required controls are not stringent enough to implement water quality standards.
The Section 303(d) Listing Methodology - 2016 Listing Cycle ("Listing Methodology") provides the listing process, the criteria for listing, and the criteria for determination of TMDL priority. The Listing Methodology was developed through a public process and finalized as a policy at a Water Quality Control Commission (Commission) administrative action hearing in March 2015.
This Listing Methodology sets forth the criteria that generally were used to make decisions regarding which waters to include on the 2016 Section 303(d) List and the 2016 M&E List. However, this methodology was not adopted by the Commission as a rule. The Commission therefore has the flexibility to take into account other appropriate factors in making site-specific listing decisions.
To determine whether Sand Creek, a portion of segment COUCNP04a, should be included on the 303(d) List rather than the M&E List, the Commission considered existing and readily available data, which includes the data used to prepare the identification processes, calculations and models referenced in 40 CFR § 130.7(a)(5)(i), (ii) and (iv), and data that was presented by Cody Resources LP/State Line Ranch.
Cody Resources LP/State Line Ranch proposed that Sand Creek be listed as impaired for sediment due to impacts to a beneficial use at the Commission's December 2015 303(d) Rulemaking. The Commission, however, placed Sand Creek on the Monitoring & Evaluation List effective March 1, 2016 based on the State Line Ranch's proposal submitted as part of written public comment. While the Commission found the evidence submitted to be persuasive and compelling evidence of impairment, the Commission was reluctant to list the segment as impaired because the proposal was made late in the process and the Division had not had an opportunity to review and evaluate the proposal. In addition, potentially affected parties were not able to participate in the process. This was the first time a segment has been listed for sediment impairing a beneficial use, and so the Commission wanted to proceed thoughtfully to establish precedent about the factors considered in such a decision. The Commission, however, stated that a proposal could be made for a special hearing to consider the sediment listing proposal. State Line Ranch subsequently requested and the Commission granted and scheduled this special hearing.
In support of listing Sand Creek as impaired, State Line Ranch submitted engineering reports prepared by Hydros Consulting, work logs from the Ranch's irrigator, and presented testimony of the Ranch President and Ranch Manager. The Commission found that Hydros appropriately analyzed the four factors required to find sediment impairment using Policy 98-1, and that State Line Ranch established with clear and convincing evidence:
The Commission has accordingly updated Colorado's List of Water-Quality-Limited Segments to move Sand Creek, a portion of Segment COUCNP04a, onto its 303(d) list from its M&E list.
The Commission considered the Division's recommendation to establish quantitative benchmarks to assess conditions on Sand Creek for future listing/delisting decisions. The Commission adopted the benchmarks proposed by Cody Resources/State Line Ranch:
For both of these recommended benchmarks, the period of assessment will need to cover several years (due to movement of existing sediment downstream and past the headgate) and include years with wet hydrologic conditions. The Commission anticipates that the Division will work with Cody Resources/State Line Ranch to implement these benchmarks because this is the first instance in which the Commission has applied Section V of Policy 98-1 since it made revisions in November 2014.
The Commission recommends that the Bureau of Land Management evaluate the impacts of off highway vehicle use in the North Sand Hills Special Recreational Management Area to water quality and sediment impairment during the next update to the Kremmling Resource Management Plan and any related Environmental Impact Statement.
PARTIES TO THE RULEMAKING HEARING
5 CCR 1002-93.16