5 Colo. Code Regs. § 1002-84.23
The provisions of sections 25-8-205(1) and 25-8-308(1)(h) C.R.S. provide the specific statutory authority for adoption of amendments to this regulation. The Commission also adopted, in compliance with section 24-4-203(4), C.R.S., the following statement of basis and purpose.
BASIS AND PURPOSE
On February 14, 2005, the Water Quality Control Division and the Joint Water Reuse Committee of the Rocky Mountain Section American Water Works Association and Rocky Mountain Water Environment Association ("Joint Committee") requested that the Commission review Regulation No. 84 for the purpose of considering additional uses of reclaimed water and other changes to the regulation. On August 8, 2005, the Commission held a rulemaking hearing during which several modifications and additions to the regulation were adopted.
As a result of this rulemaking, the Commission amended Regulation No. 84 to continue to promote the use of reclaimed water. The regulation, as amended, extends its framework to include additional uses or reclaimed water and accompanying requirements to ensure protection of public health and the environment. Specifically, the Commission is requiring reclaimed water to meet minimum standards commensurate with the risks associated with the new uses. Also, treaters and users are required to employ appropriate best management practices and to oversee the use of reclaimed water for such uses.
The Commission concludes that these amendments to Regulation No. 84 are reasonable considering the economic, environmental, and public health costs, benefits and impacts of the water reuse program.
The term "reclaimed domestic wastewater" was changed to "reclaimed water" throughout the Regulation. "Reclaimed water" is the term used in the water reuse regulations of most other states and is also used in EPA's 2004 Guidelines for Water Reuse. It is desirable to use a common term for this highly treated water as this will assist with public education efforts.
The Commission modified section 84.4 to delete provisions that are no longer applicable and relocated the exemption for irrigation at wastewater treatment facilities to the definition of Landscape Irrigation. The Commission also added, deleted, and modified definitions to increase clarity and to achieve consistency with earlier revisions to this regulation and with other regulations. The definition of "Agricultural Use" was deleted since the regulation does not address this use at this time. The definition of "Agronomic Rate" was expanded to include watering requirements of plants in order to reinforce the Commission's intent that passage of nutrients below the root zone be strictly minimized. This change operates in conjunction with revisions to sections 84.6 and 84.9 . Specific uses such as Closed Loop Cooling System, Dust Control, and Fire Protection - Non Residential were deleted from section 84.8 and are now defined in section 84.5 . The definition of "Closed Loop Cooling System" added to Section 84.5 parallels the language currently found in section 84.8 of the rule. It is the Commission's intent that all types of closed loop cooling systems falling within this definition are authorized to use reclaimed water. This includes re-circulating evaporative cooling systems and associated cooling water storage facilities that may be employed in the electric generation industry where public access is not allowed such as the use that has been in place at Platte River Power Authority since 1981. Definitions for "Resident-Controlled Landscape Irrigation" and "Fire Protection - Residential" were also added. For purposes of this regulation, residential areas are land use planning areas zoned for residential use, or otherwise designated for residential use by the applicable local land use planning authority.
The Commission revised section 84.6 to require a specific analysis, prior to issuance of a Notice of Authorization, to demonstrate that reclaimed water will be applied at agronomic rates. This was done to ensure that land application done under Regulation No. 84 is protective of ground water quality in light of the Commission's adoption of revisions to Regulation No. 61 that provide an exemption from the requirement to obtain a discharge permit, in such situations. Similarly, the Commission revised the best management practice at section 84.9 to add additional protections for ground water.
In situations where there are applicable limitations on concentration or loading of phosphorus or nitrogen under a control regulation or TMDL, the Commission modified sections 84.6 and 84.6 to provide an option, at the request of the treater, to have such limitations addressed in the Notice of Authorization. Otherwise, such limitations must be included in a discharge permit issued pursuant to Regulation No. 61.
The Commission refined section 84.6 regarding the requirement for a treater to request an amendment to the Notice of Authorization.
The Commission adopted standards and other requirements for Category 3 reclaimed water to apply to two newly authorized uses of reclaimed water. Specific Category 3 uses authorized include the use of reclaimed water for fire protection in residential areas and for landscape irrigation where a single-family resident has control of the plumbing and/or the time of irrigation. When compared with those uses where Category 1 or Category 2 reclaimed water is allowed, uses requiring Category 3 water may present an increased risk of consumption of reclaimed water due to the fact that the number of entities (e.g., single family residents) who control connections after initial construction will significantly increase and these individuals will also control the time and manner in which irrigation takes place. This increases both the possibility of a cross-connection between the reclaimed water and potable water systems and the risk of public contact with reclaimed water. Given this increased risk, the Commission adopted a standard for Category 3 reclaimed water that requires that E. coli not be detected in 75% of samples collected in any 30-day period, with a single-sample maximum for E. coli of 126 colony forming units (cfu) per 100 milliliters (ml) or a most probable number (MPN) of 126 per 100 ml, depending upon the analytical enumeration method used. This standard recognizes that it is not practical to meet a no detect standard for an indicator organism at all times and is consistent with regulatory requirements used in other states (e.g. Florida) and with the recommendations of the EPA. The rationale for selecting 126 cfu (or MPN) per 100 ml as the single sample maximum standard is consistent with the rationale supporting the E. coli standard for Category 1 and 2 reclaimed water. The Commission found that the E. coli standard is protective of the public health and environment where Category 3 reclaimed water is used in a manner compliant with the other requirements contained in the regulation.
The Commission exercised its discretion, pursuant to Citizens for Free Enterprise v. Department of Revenue, 649 P.2d 1054 (Col. 1982) to adopt these requirements based upon policy considerations about the possible increased risks to public health associated with the Category 3 uses as opposed to specific scientific evidence to that effect.
In addition to compliance with the E. coli standard, treaters and users of Category 3 reclaimed water are required to develop and implement appropriate additional best management practices, including public education, to strictly reduce the risk of cross-connections between the reclaimed water and potable water systems. Additional conditions required for Category 3 uses are listed in sections 84.8 and 84.9(A).
As revised, section 84.8(A) requires that at a minimum, the numbered conditions indicated in the last column of Table A are required for the corresponding uses. In addition, in accordance with the authority provided in section 84.6 , the Division may require additional conditions listed in section 84.8 for individual reuse activities as it determines appropriate.
The Commission decided not to include specific requirements for continuous disinfection of Category 3 reclaimed water but notes that the requirements for monitoring to determine the quality of all categories of reclaimed water should include frequent determinations to assure that disinfection is being provided prior to use.
The Commission deleted section 84.10 and added provisions to section 84.9 regarding the mechanisms that users of Category 1 reclaimed water must employ to restrict access to areas when irrigation is taking place.
In order to avoid the need to commit an excessive amount of Division resources for regulatory oversight when Category 3 reclaimed water is used, section 84.9 requires the treater to assume responsibility for the numerous residential users inherent when reclaimed water is used for resident-controlled landscape irrigation and there is not an acceptable entity (e.g., homeowners' association) to assume said responsibility.
The Commission moved the provisions of section 84.11 to subsection (B) of new section 84.10 and also added a specific requirement to report violations pursuant to new section 84.10(C)(1).
At the time the Commission initially adopted the Variance provision in Section 84.12 , it excluded authorization to the Division to provide a variance for the E. coli standards. The Commission now concludes that it is appropriate to provide a variance from the "235/100 ml single sample maximum" standard on a case-by-case basis. For example, testimony was received from the City of Fort Collins and the Platte River Power Authority concerning a use that has been in effect since 1981 without incident. Some of the effluent from the city's Drake facility is pumped 27 miles in an underground pipeline for ultimate addition to Platte River's 16,000 acre foot, 500 surface acre long term carryover storage reservoir for recirculating cooling water use at the Rawhide energy station. There is no public access to any part of the process and as a result, there is no public exposure to reclaimed water and potential worker exposure is adequately limited and controlled with safety procedures and best management practices. To avoid the necessity for capital and operational costs for investments associated with meeting the single sample maximum standard in the regulation, Fort Collins and Platte River requested a limited change in the Division's authority to grant a variance from this aspect of the E.coli standard. When Regulation 84 was adopted in 2000, the Commission noted in its Statement of Basis that reclaimed domestic wastewater systems had been constructed and been in operation prior to the adoption of the regulation. It was emphasized that this regulation is not intended to force existing systems to make capital improvements solely for assuring standardization if they accomplish the objectives of this regulation. The Commission has determined it is appropriate to provide authority to the Division to grant a variance from the single sample maximum standard when it concludes that the cost of compliance does not bear a reasonable relationship to the environmental or public health benefits.
As noted in the Statement of Basis when the Commission added E.coli to the Basic Standards for Surface Waters in 2000, there is great variability in individual bacteriological samples because bacteria are not uniformly distributed in water samples. A single sample may give a false impression of potential risk of violation of a standard based on a geometric mean. In cases where there is limited or no public exposure and potential worker exposure is controlled by best management work place standards, the resulting lower risk warrants the option for the Division to consider a variance from the single sample maximum standard.
The Commission also corrected references to "E coli" in Regulation No. 84 to the italicized E coli.
PARTIES TO THE RULEMAKING HEARING
5 CCR 1002-84.23