Maximum Contaminant Levels and Monitoring Requirements

PURPOSE: This rule establishes sampling and monitoring requirements for public water systems and criteria for significant defiencies at surface water systems. (1) The rules in this chapter contain maximum contaminant levels (MCLs) permissible in public water systems and describe associated monitoring requirements. A supplier of water must collect or have collected samples of the water and shall provide for analysis of these samples for designated contaminants. Nothing in this chapter shall preclude a duly designated representative of the department from taking samples or from using the results from the samples to determine compliance by a supplier of water with applicable provisions of these rules. (2) Laboratory services required by this chapter to determine contaminant levels are available from the Department of Natural Resources (DNR) or the Department of Health according to the fee schedule set out in 10 CSR 60-16.030. (A) Samples must be collected at no less than the required frequency and in accordance with schedules established by the department when samples are submitted to the DNR or the Department of Health laboratory for analysis. (B) A supplier of water which submits samples to the DNR or the Department of Health laboratory must collect and submit samples using containers provided by the department in accordance with the instructions enclosed. (C) A supplier of water not using the DNR or the Department of Health laboratory must have the analysis done by a laboratory certified by the department. (3) Samples taken to determine compliance with the requirements of this chapter shall be taken at representative points of the public water system, as approved by the department. The supplier of water shall provide satisfactory sampling taps. Samples for microbiological analysis must be received in the laboratory for analysis within thirty (30) hours of collection. (4) All analytical results must be accurate to at least the same number of significant figures as the applicable MCL. (5) All analyses must be consistent with the methods and procedures described in 10 CSR 60-5.010 and 10 CSR 60-5.020. The results of all analyses must be used to determine compliance with the MCLs unless the analytical results are invalidated for technical reasons, such as obvious sampling errors. (6) When a public water supply system supplies water to one (1) or more other public water supply systems, the department may modify the monitoring requirements imposed by these rules to the extent that the interconnection of the systems justifies treating them as a single system for monitoring purposes. Any modified monitoring must be conducted pursuant to a schedule specified by the department. (7) Inspections and Sanitary Surveys of Surface Water Systems. (A) Sanitary surveys of all surface water systems and systems using groundwater under the direct influence of surface water will be conducted at least every three (3) years for community systems and every five (5) years for noncommunity systems. Sanitary survey as used in this section (7) means an on-site review, under the supervision of an engineer, of the water source (identifying its sources of contamination using the results of source water assessments where available), facilities, equipment, operation, maintenance, and monitoring compliance, in order to evaluate the adequacy of the system, its sources and operations and the distribution of safe drinking water. It also includes a review of the disinfection profile for systems that are required to comply with disinfection profiling requirements. (B) For community water systems determined by the department to have no significant deficiencies (for example, defects or inadequacies that increase risk from waterborne disease, such as deficiencies involving the removal, inactivation or reintroduction of pathogens or prevention or removal of chemical contamination) in two (2) consecutive sanitary surveys, the frequency of sanitary surveys may be decreased to once every five (5) years. Upon finding a significant deficiency, the department may return the community water system to the three (3)-year schedule. (C) Public water systems must respond in writing to significant deficiencies outlined in sanitary survey reports no later than fortyfive (45) days after receipt of the report. The response must indicate how and on what schedule the system will address significant deficiencies noted in the survey. Failure to respond within forty-five (45) days is a violation. Public water systems shall take necessary steps to address significant deficiencies identified in sanitary survey reports if such deficiencies are within the control of the public water system and its governing body. (D) The department, at its discretion, may conduct routine inspections of any public water system or make other necessary inspections to determine compliance with these rules. If, after investigation, the department finds that any public water system is incompetently supervised, improperly operated, inadequate, of defective design or if the water fails to meet standards established in 10 CSR 60, the water supplier must implement changes that may be required by the department. (8) The provisions of this rule are declared severable. If any fee fixed by this rule is held invalid by a court of competent jurisdiction or by the Administrative Hearing Commission, the remaining provisions of this rule shall remain in full force and effect, unless otherwise determined by a court of competent jurisdiction or by the Administrative Hearing Commission. AUTHORITY: section 640.100, RSMo Supp. 2003.* Original rule filed May 4, 1979, effective Sept. 14, 1979. Amended: Filed April 14, 1981, effective Oct. 11, 1981. Amended: Filed Aug. 13, 1982, effective Jan. 13, 1983. Amended: Filed June 2, 1988, effective Aug. 31, 1988. Amended: Filed Dec. 4, 1990, effective July 8, 1991. Amended: Filed April 14, 1994, effective Nov. 30, 1994. Amended: Filed Dec. 15, 1999, effective Sept. 1, 2000. Amended: Filed April 15, 2003, effective Jan. 30, 2004. *Original authority: 640.100, RSMo 1939, amended 1978, 1981, 1982, 1988, 1989, 1992, 1993, 1995, 1996, 1998, 1999, 2002.