5 Colo. Code Regs. § 1002-11.55
Adoption of Amendments to Article 13 - Groundwater Rule, with amendments to Articles 1, 3, 5, 7, 9, and 10 of the Colorado Primary Drinking Water Regulations.
The Colorado Revised Statutes (CRS), § 25-1.5-202, provide specific authority for adoption of these regulatory amendments. The Commission also adopted, in compliance with § 24-4-103(4), CRS, the following statement of basis and purpose.
BASIS AND PURPOSE
All suppliers of drinking water in Colorado are subject to regulations adopted by the U.S. Environmental Protection Agency (EPA) under the Safe Drinking Water Act, (42 U.S.C. 300f et seq.) as well as by the Colorado Primary Drinking Water Regulations under the direction of the Water Quality Control Division (Division). Colorado has been granted primary enforcement responsibility (primacy) for the public water system supervision program under the federal Safe Drinking Water Act. However, in order to maintain primacy, states must also promulgate new regulations that are no less stringent than those adopted by the federal government. By retaining primacy, the Division is able to protect the public health by ensuring that public water systems provide safe drinking water to Colorado citizens and visitors.
Article 13 (Groundwater Rule) of the Colorado Primary Drinking Water Regulations was adopted on 12/08/2008. While the majority of the provisions in Article 13 were required to maintain primacy and are based on federal language, Section 13.2 does not contain federal requirements and Colorado's primary enforcement authority was not contingent upon its adoption. The substance of Section 13.2 covers Colorado rules on the disinfection of groundwater sources and the rules for granting public water systems a waiver from disinfection requirements.
The Center for Disease Control has called providing safe drinking water one of the greatest public health achievements of the 20th century. Prior to 1908, no U.S. municipal water systems chemically disinfected drinking water. Consequently, waterborne diseases exacted a heavy toll in illness and death. Without chlorination or other disinfection processes, the public is at great risk of contracting waterborne diseases. Meeting the goal of clean, safe drinking water requires a multi-barrier approach that includes protecting raw source water from contamination, appropriately treating raw water, and ensuring safe distribution of treated water to consumers' taps.
Water-borne disease outbreaks have been common in Colorado dating back to the 1800s. As a result, mandatory disinfection of all water served to the public, including groundwater sources, has long been recognized by both the Colorado Board of Health and subsequently the Water Quality Control Commission as necessary for the protection of public health. This recognition predates the federal Safe Drinking Water Act. Disinfection of groundwater sources has always been included in mandatory disinfection requirements and Colorado has a regulatory history that views untreated groundwater as a potentially significant health hazard.
In November 1967, the Colorado Board of Health recognized that mandatory disinfection of drinking water served to the public was necessary to protect public health and the Board amended then existing regulations to include the requirement that "a sufficient amount of chlorine shall be added to the water to maintain a measurable chlorine residual at all points in the distribution system." The Board also established, at that time, the ability of the Water Quality Control Division (WQCD) to grant groundwater systems a waiver from disinfection requirements if the system could demonstrate that their water was "reasonably safe and free from contamination."
In 1977, the Board further strengthened disinfection requirements by adopting amendments that required systems to maintain a "free available chlorine residual of at least 0.2 mg/L at the extremities of the distribution system." Amendments adopted in 1991, modified the requirement for maintaining a chlorine residual in the distribution system from 0.2 mg/L to maintaining a "detectable residual in at least 95% of the samples taken at the extremities of the distribution system." An amendment requiring a residual disinfectant concentration in the distribution system measured "at the same time as total coliforms are sampled" was also added.
Based on the regulatory authority established in the 1967 amendments, WQCD issued disinfection waivers dating back over several decades. Concerns with the ongoing appropriateness of some of these existing waivers prompted the initiation of a waiver review process in 2007. This process resulted in the withdrawal of a number of disinfection waivers due to concerns over the system's ability to provide safe drinking water to the public.
Recently, two disease outbreaks associated with groundwater systems occurred in Colorado - the 2008 salmonella outbreak in Alamosa and the Skyline Ranch norovirus outbreak in 2007. The Alamosa outbreak was particularly serious due to the large number of people who were sickened and one death associated with this particular disease outbreak. Alamosa had a disinfection waiver at the time of the outbreak (which has since been withdrawn) and, as a result, the city's drinking water was not being disinfected. An extensive report was developed in the wake of the Alamosa outbreak. This report outlined a combined failure of physical, regulatory and human infrastructure all of which contributed to the outbreak.
After careful consideration, in particular, of the history of disinfection in Colorado, of the historical issuance of disinfection waivers, of the reality of continued disease outbreaks, and of growing concerns with the clarity of regulatory language, the amendments as described in this article (Article 25) were developed and adopted. These amendments reflect several conclusions. Retention of waivers is not appropriate except for systems that have shown a consistent, long-term history of operating in a manner that is fully protective of public health without the barrier of disinfection and can demonstrate continuing adherence to high standards of source and distribution system protection. Increased requirements and oversight of systems that continue to operate under disinfection waivers is appropriate. The issuance of waivers to new water systems poses too high a risk to public health given that new systems cannot clearly demonstrate a long-term history of being able to successfully operate without disinfection. Furthermore, it is not appropriate for systems that are currently providing chemical disinfection to discontinue such disinfection thereby removing a demonstrably effective primary barrier to microbial contamination. Systems serving populations susceptible to microbial contamination, specifically schools and day care centers, are unsuitable to operate without chemical disinfection due to the increased health risks these types of populations face.
For those systems that are required to disinfect, further conclusions were reached. Clarification of continuous chemical disinfection requirements was needed. Clarification of entry point and distribution system monitoring and compliance requirements was needed. It was recognized that systems providing only ultraviolet treatment as a means of disinfection are not providing sufficiently protective disinfection due to the inability of ultraviolet treatment to maintain a disinfection residual. It was recognized that there are inherent difficulties requiring hand pumped wells to maintain continuous disinfection due to their typically remote locations. Therefore, there was a need to establish criteria for proper operation, maintenance and monitoring of such wells. Finally, it was concluded that amendments clarifying the recordkeeping, reporting and public notice requirements for groundwater systems were needed.
These amendments clarify and expand upon long standing requirements of the Colorado Primary Drinking Water Regulations, and are in line with requirements that are already part of existing guidance and/or policy. The overall goal of these amendments is to further protect the public from microbial contamination and to enhance Article 13 regarding specific regulations that apply to groundwater systems. These amendments primarily revise the previously adopted Section 13.2 and add a recordkeeping section (Section 13.5) and a reporting section (Section 13.6).
Summary
Groundwater Disinfection Amendments. The Commission has amended the Colorado Primary Drinking Water Regulations concerning minimum treatment technique requirements for groundwater systems in the following ways. Requirements in Article 1 were redesignated to Article 9, a requirement to Article 5 was added and requirements were revised and added to Articles 9 and 13.
Primary Enforcement Responsibility Amendments.The Commission adopted amendments to the Colorado Primary Drinking Water Regulations in order to remain consistent with provisions of the National Primary Drinking Water Regulations which were amended to include revisions concerning approved analytical methods and revisions concerning compliance monitoring requirements. The federal provisions were published in the following Federal Registers:
The federal regulations as published in the Federal Register, Volume 74, Number 123, June 29, 2009, pages 30953 through 30959, National Primary Drinking Water Regulations: Minor Correction to Stage 2 Disinfectants and Disinfection Byproducts Rule and Changes in References to Analytical Methods
The federal regulations as published in the Federal Register, Volume 74, Number 216, November 10, 2009, pages 57908 through 57918, Expedited Approval of Alternative Test Procedures for the Analysis of Contaminants Under the Safe Drinking Water Act; Analysis and Sampling Procedures
The federal regulations as published in the Federal Register, Volume 74, Number 230, December 2, 2009, pages 63069 through 63070, Expedited Approval of Alternative Test Procedures for the Analysis of Contaminants Under the Safe Drinking Water Act; Analysis and Sampling Procedures
The revised analytical methods concerned microbial contaminants, surface water minimum disinfectant residuals, maximum disinfectant residuals, disinfectant byproducts, disinfectant byproducts precursors, and secondary maximum contaminates. These amendments added language to sections 3.4 , and multiple sections of Article 10.
The revised compliance monitoring requirements concerned stage 2 disinfection byproducts routine monitoring. These amendments had to be adopted to maintain primary enforcement authority. These amendments revised Tables 7-29 and 7-33.
Additionally, the Commission adopted amendments removing Section 1.9.1 concerning consecutive public water systems in order to remain consistent with and at least as stringent as regulations adopted by the federal government.
Other Amendments to the Colorado Primary Drinking Water Regulations. The Commission adopted amendments to the Colorado Primary Drinking Water Regulations that added, corrected, removed or revised obsolete references and dates, spelling, typographical and reference errors. This was done to provide clarity and accuracy.
Groundwater Disinfection Requirements.
The Commission amended Articles 1, 5, 9 and 13 of the Colorado Primary Drinking Water Regulations to include the following requirements as summarized below:
- Groundwater disinfection requirements
- Groundwater Source (13.1(a)(7-8), 13.2(a)(1),13.2(a)(2)(i), 13.2(b)(1), 13.2(b)(3) and 13.2(c)(1))
- Establishes minimum treatment techniques requiring groundwater systems to disinfect a groundwater source at all times that the source is serving water to the public. The disinfection must include chemical treatment resulting in at least 0.2 mg/L residual disinfectant concentration in water entering the distribution system at the entry points.
- Establishes weekly residual disinfectant concentration monitoring at all entry points serving groundwater to the public. The monitoring requirement increases to every 24 hours while the residual disinfectant concentration is below 0.2 mg/L.
- Establishes a timeframe of 72 hours to correct a residual disinfectant concentration that is discovered to be below 0.2 mg/L, otherwise a treatment technique violation occurs.
- Establishes that a groundwater system in violation of the treatment technique must resolve and document the situation, keep records, notify the Department and issue public notice.
- Establishes when a system that is chlorinating needs to begin compliance with monitoring requirements.
- Establishes when a system disinfecting with only ultra violet light must begin additional required chemical disinfection.
- Groundwater distribution system (13.2(a)(2)(ii), 13.2(b)(2), 13.2(b)(3) and 13.2(c)(2))
- Establishes at least a detectable residual disinfectant concentration throughout the distribution system to be measured at the same point and time as total coliform.
- Establishes residual disinfectant concentration cannot be undetectable in more than 5 percent of the measurements taken each monitoring period for any two consecutive monitoring periods, otherwise a treatment technique violation occurs.
- Establishes that a groundwater system in violation of the treatment technique must issue public notice.
- Groundwater disinfection waiver requirements (9.2.12, 13.1(a)(1)(i), 13.1(a)(9), 13.1(a)(14), 13.2(d) and 13.5(a)(3))
- Establishes that groundwater systems with a disinfection waiver prior to November 30, 2010, will continue to have a disinfection waiver and are not subject to groundwater disinfection requirements in 13.2(a-c).
- Establishes that a groundwater system with a disinfection waiver that is determined to be a school or a daycare center will no longer have a disinfection waiver.
- Establishes Department authority to revoke disinfection waivers from groundwater systems with susceptible populations.
- Establishes that the Department will no longer issue new disinfection waivers.
- Establishes that a groundwater system with a disinfection waiver must comply with the following:
- Provide public notice that the system operates under a disinfection waiver.
- Ensure that the system is operated by a certified operator.
- Have emergency disinfection or an emergency disinfection plan.
- Keep records of all chlorination activities.
- Have a Monitoring Plan.
- Protect their distribution system (Distribution System Protection Plan).
- Protect their groundwater sources (Source Water Protection Plan).
- Establishes Department authority to:
- Evaluate any groundwater source or storage system using Department Design Criteria and CRS Well Construction Criteria.
- Require sampling of any groundwater source.
- Require sampling and proof that new groundwater sources are not contaminated.
- Perform a sanitary survey of the system at any time.
- Review the violation history of the system.
- Withdraw a waiver from a system with a fecally contaminated source.
- Withdraw the disinfection waiver.
- Establishes that the groundwater system has the right of appeal to a Department decision to withdraw a disinfection waiver.
- Groundwater systems with hand pumped well requirements (5.1.1(e)(6), 9.2.14, 13.1(a)(1)(ii-iii), 13.2(e))
- Establishes that groundwater systems with hand pumped wells must comply with the following:
- Operate according to Department guidance or Department approved alternative guidance.
- Disinfect hand pumped wells before opening for the season.
- Monitor for total coliform at least once a month.
- Take a hand pumped well out of service if it is contaminated. The system must eliminate the contamination and disinfect the hand pumped well before the well can be put back into service.
- Continuously post public notice whenever the hand pump well is available for public use. (9.2.14(b))
Primary Enforcement Responsibility Requirements.
The Commission amended Articles 1, 3, 7 and 10 of the Colorado Primary Drinking Water Regulations to revise or add the following requirements as summarized below:
- Consecutive System Requirements (1.9)
- Removed Section 1.9.1 . This section allowed for an exemption from regulation under the Colorado Primary Drinking Water Regulations for consecutive public water systems. This exemption made the Colorado Primary Drinking Water Regulations less stringent than regulations adopted by the federal government.
- Analytical methods (3.4, 10.1.3(c), 10.1.4(a))
- Standard Methods 21st Addition approved for multiple methods.
- Additional approved methods for residual chlorine analysis including On-Line Chlorine Analyzer EPA 334.0 and Test Strips Method D99-003.
- Stage 2 disinfection byproducts routine monitoring (Tables 7-29 and 7-33)
- Community and non-transient non-community water systems that serve only groundwater with a population less than 500 may take individual TTHM and HAA5 samples. Community and non-transient non-community water systems that serve surface water with a population less than or equal to 3,300 may take individual TTHM and HAA5 samples. All others must take dual sample sets.
Other Requirements of the Colorado Primary Drinking Water Regulations.
The Commission amended the Colorado Primary Drinking Water Regulations to add, correct, remove or revise the following requirements as summarized below:
- Monitoring Plan (1.12)
- Public water system must submit one copy of the monitoring plan instead of two.
- Additional Analytical Methods (Article 10)
- Section 10.12 and Table 10-30 was added.
- First paragraph reference to Tables10-23 and 10-24 is corrected to be 10-24 and 10-27
- Sanitary Survey Frequency and Response to Significant Deficiencies or Violations of Colorado Primary Drinking Water Regulations in a Sanitary Survey Written Notice (11.2 and 11.4)
- Language referencing December 1, 2009 is now obsolete and is removed.
Discussion Items.
These amendments to the Colorado Primary Drinking Water Regulations were developed in consultation with stakeholders. Stakeholders were provided opportunities to express concerns regarding particular provisions of the amendments and today's amendments have addressed many of those comments. The discussion below reflects conclusions of major comments.
Entry Point Monitoring:
These amendments were intended to achieve several levels of public health protection and required that all groundwater sources be disinfected at all times that they are used to serve water to the public and required that disinfection at least include one chemical treatment method. As a means to verify sufficient disinfection of the source entry point monitoring has been established. Since the amendments require the use of chemical disinfection, measurement of residual disinfectant concentration at each entry point to the distribution system ensures that chemical disinfection is being provided. Additionally, monitoring is required at entry points that have served water to the public during the monitoring period, meaning when water from a groundwater source is available to a consumer in any way, sampling is required at that source's entry point. Conversely, when no water enters the distribution system from a source or a number of sources that combine before entering the distribution system, then no monitoring is required to confirm that treatment is being delivered.
It is recognized that some groundwater systems operate continuous chlorine analyzers at the entry points to the distribution system. With a minimum monitoring requirement of once per week per entry point, it is apparent that monitoring more frequently meets this requirement. The amendments require action on behalf of the groundwater system when the system discovers that the residual disinfectant concentration falls below the minimum disinfectant level and therefore the system must be aware of this event. At a minimum, these systems must make themselves aware of the residual disinfectant concentration once a week. Although this will meet the minimum monitoring requirement, systems are required to take proper follow up action any time they become aware of a residual disinfectant concentration measurement that falls below the minimum. Additionally, systems must keep records of entry point compliance monitoring. Chart recordings and data logs meet this requirement as long as they record all pieces of information required by the recordkeeping requirements of the amendments and make note of the recordings they will use for compliance.
Minimum Entry Point Residual Disinfectant Concentration:
The amendments identify a minimum level of disinfectant of 0.2 mg/L of chlorine that must be maintained at the entry points to the distribution system. This level is appropriate as demonstrated in the history of the Colorado Primary Drinking Water Regulations as well as in requirements of the Surface Water Treatment Rule of 1989. The Colorado Primary Drinking Water Regulations have previously required 0.2 mg/L of residual disinfectant concentration at all points in the distribution system. In addition, at least 7 other states require at a minimum 0.2 mg/L residual disinfectant concentration throughout the entire distribution system. Additionally, given that a large percentage of groundwater sources contain known chlorine measurement interferences, establishing an entry point free chlorine residual requirement that is well above method detection limits, ensures that systems will be providing an actual free chlorine residual at least at the entry points to the distribution system.
Entry Point Treatment Technique Violation:
The amendments establish the point at which a system has violated the groundwater source treatment technique. Upon discovery of the insufficient residual disinfectant concentration the system must begin sampling the entry point every 24 hours until the residual disinfectant concentration is restored to at least 0.2 mg/L. Additionally, upon observing a measurement of the residual disinfectant concentration below 0.2 mg/L the system has 72 hours to restore the residual to at least 0.2 mg/L before the system incurs a treatment technique violation. It is the system's responsibility to notify the Water Quality Control Division when a treatment technique violation has occurred. Regular reporting of weekly entry point sampling data is not required unless the Water Quality Control Division identifies the need to collect and maintain this information (pursuant to Section 1.6.4).
Considering that treatment technique violations require Tier 2 public notification, it is considered burdensome to require that level of notification when disinfection has failed for only a short period of time if the water has not been identified as contaminated. However, extended periods where disinfection is not being applied (longer than 72 hours) does constitute an elevated level of public health risk that warrants a Tier II public notification. The 72 hour time period does allow for the system to make progress towards resolving the issue concerning the insufficient level of disinfectant as well as time to contact the Water Quality Control Division to request assistance and guidance.
Waivered Systems Introducing New sources:
Systems that have maintained a waiver from disinfection, just like many other water systems in Colorado, face issues of water scarcity and growing populations and therefore may require the addition of new sources to the system. Although, the amendments identify that issuing new waivers is not appropriate, systems that have shown a history of operating in a manner that is fully protective of public health without the barrier of disinfection may continue that operation with the addition of new groundwater sources that are shown to be free of contamination and properly constructed.
Systems that wish to maintain a waiver from disinfection cannot add a groundwater source that is contaminated or comes from a well that has been improperly constructed. Furthermore, the addition of a source that is a surface water source or is identified as a groundwater under the direct influence of surface water source will result in immediate waiver withdrawal.
5 CCR 1002-11.55