Effective Date: December 30, 1992

5-1.50 Applicability and responsibility.

Subpart PUBLIC WATER SYSTEMS; MAXIMUM CONTAMINANT LEVELS; MONITORING REQUIREMENTS; NOTIFICATIONS REQUIRED

The provisions of sections 5-1.50 through 5-1.52 of this Subpart shall apply to all public water systems. The supplier of water of a public water system is responsible for completion of the monitoring requirements set forth in such sections and for performing all analyses in accordance with the analytical requirements set forth in Appendix 5-C of this Subpart. At the discretion of the State, analyses performed by the State may be used for monitoring purposes.

Effective Date: November 9, 2011

5-1.51 Maximum contaminant levels, maximum residual disinfectant levels and treatment technique requirements.

(a) The maximum contaminant levels, maximum residual disinfectant levels and treatment technique requirements are listed in section 5-1.52 tables 1 through 7 of this Subpart. In the case where a MCL, MRDL, or treatment technique requirement is exceeded, notwithstanding anything to the contrary contained in section 5-1.12 of this Subpart, the supplier of water will take the necessary steps to comply with this section, to ensure the protection of the public health, including the undertaking of remedial feasibility studies and the installation of a suitable treatment process. Compliance with the MCLs, MRDLs and treatment technique requirements shall be determined by the procedures contained in section 5-1.52 tables 1 through 7 of this Subpart.

(b) The minimum monitoring requirements for each contaminant are listed in section 5-1.52 tables 8A through 12 and 15A of this Subpart, except for public water systems with fewer than 15 service connections and which serve fewer than 25 persons, where monitoring will be at State discretion. For this section, State discretion shall mean requiring monitoring when the State has reason to believe an MCL, MRDL, or treatment technique requirement has been violated, the potential exists for an MCL, MRDL, or treatment technique violation or a contaminant may present a risk to public health.

(c) Each system must develop and implement a monitoring plan that includes all monitoring requirements specified in this Subpart. This plan must be completed by January 31, 2012. The system must maintain the plan and make it available for inspection by the State and the general public. After review, the State may require changes in any plan elements. Failure to monitor in accordance with the monitoring plan is a monitoring violation. Systems may only use data collected in accordance with the monitoring plan to qualify for reduced monitoring. The monitoring plan must include at least the following elements, as applicable:

(1) specific locations and schedules for collecting samples for all applicable parameters listed in section 5-1.42, section 5-1.43, Tables 8A-12 of section 5-1.52, and section 5-1.61 of this Subpart;

(2) how the system will calculate compliance with MCLs, MRDLs, and treatment techniques;

(3) if the system is a consecutive system, or it is providing water to a consecutive system, and has been approved for modified monitoring under the provisions of section 5-1.76 of this Subpart, the sampling plan must reflect the entire distribution system for any analytes approved for modified monitoring;

(4) consecutive ground water systems must define and implement a protocol for notifying the system from which they receive water of any total coliform positive samples so the source can be tested for fecal contamination, unless the wholesale ground water system provides 4-log virus treatment at peak flow before or at the first customer as confirmed through process compliance monitoring.

(d) The notification requirements for each contaminant are listed in section 5-1.52 table 13 of this Subpart.

(e) The CT values for inactivation of Giardia lamblia cysts by free chlorine at various pH and temperature levels are listed in section 5-1.52 tables 14A through 14F of this Subpart. The CT values for inactivation of Giardia lamblia cysts by chlorine dioxide and ozone at various temperature levels are listed in section 5-1.52 table 14G of this Subpart.

(f) The alternative disinfection monitoring frequency requirements using grab samples instead of continuous chlorine concentration monitoring is listed in section 5-1.52 table 15 of this Subpart.

EHM item PWS-35 from 1992-05-29 refers to 5-1.51(f). In the 90's that paragraph read (f) Monitoring and reporting frequencies for specific contaminants may be established at State discretion whenever the State believes that a potential exists for an MCL violation or the contaminant may present a risk to public health.

(g) Monitoring and reporting frequencies for specific contaminants may be established at State discretion whenever the State believes that a potential exists for an MCL or MRDL violation or a contaminant may present a risk to public health.

(h) Notwithstanding anything to the contrary in subdivision (a) of this section, the Commissioner may recommend values lower than the MCLs if sufficient valid information based on commonly accepted scientific standards and principles demonstrates an increased public health concern. Within one year from the date of such recommendation, the State shall hold a public hearing regarding the justification for the lower value, and whether a new MCL is warranted.

(i) Notwithstanding anything to the contrary in section 5-1.52 table 3, the Commissioner may in specific cases except specific organic chemicals from the MCLs for general organic chemicals if the supplier of water can demonstrate that sufficient valid scientific information exists to show that the organic chemical does not pose an unreasonable risk to human health, the organic chemical is present at a level and under circumstances not indicative of contamination, and the cost of compliance is unreasonable in light of the risk to human health.

(j) Notwithstanding anything to the contrary in section 5-1.52 table 3 of this Subpart, the Commissioner may, based on receipt and review of a justification submitted by the supplier of water, allow a higher MCL for a period of up to 60 days following application of a paint or lining to a potable water structure, if he determines that an unreasonable risk to human health does not exist.

(k) Notwithstanding anything to the contrary in section 5-1.52 table 3A of this Subpart, systems may increase residual disinfectant levels of chlorine or chloramines (but not chlorine dioxide) in the distribution system to a level and for a time necessary to protect public health, to address specific microbiological contamination problems caused by circumstances such as, but not limited to, distribution line breaks, storm run-off events, source water contamination events, or cross-connection events.

(l) A system that is installing granular activated carbon (GAC) or membrane technology to comply with the trihalomethane and haloacetic acid MCLs listed in section 5-1.52 table 3 may apply to the State for an extension of up to 24 months past the compliance dates for those MCLs. Systems must comply with any interim measures and schedules of compliance set by the State.

(m) Each public water system must certify annually in writing to the State that when Acrylamide and Epichlorohydrin are used in drinking water systems, the combination (or product) of dose and monomer level does not exceed the levels specified as follows:

Acrylamide = 0.05% dosed at 1 ppm (or equivalent)

Epichlorohydrin = 0.01% dosed at 20 ppm (or equivalent)

Certification can rely on manufacturers or third parties, as approved by the State.

(n) For microbiological analysis, a standard sample size of 100 milliliters shall be used.

Effective Date: May 26, 2004

5-1.52 Tables.

MAXIMUM CONTAMINANT LEVEL DETERMINATION
1. Inorganic Chemicals and Physical Characteristics
2. Nitrate, Nitrite, Total Nitrate/Nitrite
3. Organic Chemicals
3A. Maximum Residual Disinfectant Level
4. Entry Point Turbidity
4A. Surface Water Turbidity
5. Distribution System Turbidity
6. Microbiological
7. Radiological

MINIMUM MONITORING REQUIREMENTS
8A. Asbestos
8B. Inorganic Chemicals
8C. Nitrates; Nitrites
8D. Other Chemicals
9A. Organic Chemicals - Disinfection Byproducts
9B. POCs, Vinyl Chloride and VOCs
9C. Pesticides, Dioxins and PCBs
9D. Specific POCs
10. Turbidity
10A. Turbidity
11. Microbiological Minimum Monitoring Requirements
11A. Microbiological/Filtration avoidance criteria
11B. Repeat Microbiological Sampling Requirements
12. Radiological

NOTIFICATION
13. Required Notification

CT DETERMINATION
14A-G. CT Values

MISCELLANEOUS
15. Entry Point Disinfection Monitoring
15A. Disinfection Residual Minimum Distribution System Monitoring
16. Additional Contaminants for which Reporting is Required Pursuant to 5-1.72(e)-(h)
17. Information Collection Rule Contaminant Reporting Requirements