Maximum contaminant levels, action levels, treatment technique requirements, and maximum residual disinfectant levels

1. Inorganic chemicals. The maximum contaminant levels, action levels, and treatment technique requirements for inorganic chemical contaminants excluding disinfection byproducts shall be as prescribed by the department and set forth under title 40 Code of Federal Regulations, part 141 subpart G. CONTAMINANT MAXIMUM CONTAMINANT LEVEL MILLIGRAM(S) PER LITER ACTION LEVEL MILLIGRAM(S) PER LITER TREATMENT TECHNIQUE REQUIREMENTS Antimony 0.006 Arsenic 0.010 Asbestos 7 million fibers per liter (longer than ten micrometers) Barium 2 Beryllium 0.004 Cadmium 0.005 Chromium 0.1 Copper The 90th percentile level must be less than or equal to 1.3 Source water and corrosion control treatment Cyanide (as free cyanide) 0.2 Fluoride 4.0 Lead The 90th percentile level must be less than or equal to 0.015 Source water and corrosion control treatment, public education, and lead service line replacement Mercury 0.002 Nickel 0.1 Nitrate (as N) 10 Nitrite (as N) 1 Selenium 0.05 Thallium 0.002 Total Nitrate and Nitrite (as N) 10 At the discretion of the department, nitrate levels not to exceed twenty milligrams per liter may be allowed in a noncommunity water system if the supplier of water demonstrates to the satisfaction of the department that: a. Such water will not be available to children under six months of age; b. There will be continuous posting of the fact that nitrate levels exceed ten milligrams per liter and the potential health effect of exposure; c. Local and state public health authorities will be notified annually of nitrate levels that exceed ten milligrams per liter; and d. No adverse health effects shall result. 2. Organic chemicals. The maximum contaminant levels and treatment technique requirements for organic chemical contaminants excluding disinfection byproducts and disinfection byproduct precursors shall be as prescribed by the department and set forth under title 40 Code of Federal Regulations part 141, subpart G. CONTAMINANT MAXIMUM CONTAMINANT LEVEL MILLIGRAM(S) PER LITER TREATMENT TECHNIQUE REQUIREMENTS Nonvolatile Synthetic Organic Chemicals: Acrylamide The combination (or product) of dose and monomer level may not exceed 0.05 percent dosed at 1 part per million (or equivalent) Alachlor 0.002 Atrazine 0.003 Benzo (a) pyrene 0.0002 Carbofuran 0.04 Chlordane 0.002 Dalapon 0.2 Dibromochloropropane (DBCP) 0.0002 Di (2-ethylhexyl) adipate 0.4 Di (2-ethylhexyl) phthalate 0.006 Dinoseb 0.007 Diquat 0.02 Endothall 0.1 Endrin 0.002 Epichlorohydrin The combination (or product) of dose and monomer level may not exceed 0.01 percent dosed at 20 parts per million (or equivalent) Ethylene dibromide (EDB) 0.00005 Glyphosate 0.7 Heptachlor 0.0004 Heptachlor epoxide 0.0002 Hexachlorobenzene 0.001 Hexachlorocyclopentadiene 0.05 Lindane 0.0002 Methoxychlor 0.04 Oxamyl (Vydate) 0.2 Polychlorinated biphenyls (PCBs) 0.0005 Pentachlorophenol 0.001 Picloram 0.5 Simazine 0.004 Toxaphene 0.003 2,3,7,8-TCDD (Dioxin) 0.00000003 2,4-D 0.07 2,4,5-TP Silvex 0.05 Volatile Synthetic Organic Chemicals: Benzene 0.005 Carbon tetrachloride 0.005 p-Dichlorobenzene 0.075 o-Dichlorobenzene 0.6 1,2-Dichloroethane 0.005 1,1-Dichloroethylene 0.007 cis-1,2-Dichloroethylene 0.07 trans-1,2-Dichloroethylene 0.1 Dichloromethane 0.005 1,2-Dichloropropane 0.005 Ethylbenzene 0.7 Monochlorobenzene 0.1 Styrene 0.1 Tetrachloroethylene 0.005 Toluene 1 1,2,4-Trichlorobenzene 0.07 1,1,1-Trichloroethane 0.2 1,1,2-Trichloroethane 0.005 Trichloroethylene 0.005 Vinyl chloride 0.002 Xylenes (total) 10 3. Filtration and disinfection treatment. a. General requirements. All subpart H systems that utilize surface water sources shall provide filtration and disinfection treatment. All subpart H systems that utilize ground water sources deemed by the department to be under the direct influence of surface water shall provide disinfection treatment and shall either comply with filtration avoidance criteria or provide filtration treatment. b. Treatment technique requirements. The department hereby identifies filtration and disinfection as treatment techniques to protect against the potential adverse health effects of exposure to giardia lamblia, cryptosporidium, legionella, viruses, heterotrophic plate count bacteria, and turbidity. The treatment techniques apply only to subpart H systems. Subpart H systems that serve ten thousand or more persons shall be deemed to be in compliance with the treatment techniques if the requirements set forth under title 40 Code of Federal Regulations part 141, subparts H and P, are met. Subpart H systems that serve fewer than ten thousand persons shall be deemed to be in compliance with the treatment techniques if the requirements set forth under title 40 Code of Federal Regulations part 141, subpart H, are met. 4. Radioactivity. The maximum contaminant levels for radioactivity are as follows: CONTAMINANT MAXIMUM CONTAMINANT LEVEL (MCL) Combined radium-226 and radium-228 5 picocuries per liter (pCi/L) Gross alpha particle activity (including radium-226, but excluding radon and uranium) 15 picocuries per liter (pCi/L) Uranium 30 micrograms per liter (ug/L) 5. Microbiological. The treatment technique triggers, treatment technique violations, E. coli maximum contaminant level violations, and monitoring violations are as follows: a. Treatment technique triggers. A system must conduct assessments, in accordance with the requirements under title 40 Code of Federal Regulations part 141, subpart Y after exceeding the following treatment technique triggers: (1) Level 1 treatment technique triggers. (a) A system, which collects forty or more samples per month, exceeds 5.0 percent total coliform-positive samples per month. (b) A system, which collects less than forty samples per month, has two or more total coliform-positive samples per month. (c) A system fails to take all required repeat samples following a total coliform-positive sample. (2) Level 2 treatment technique triggers. (a) A system incurs an E. coli maximum contaminant level violation, as specified in title 40 Code of Federal Regulations part 141, subpart Y. (b) A system has a second level 1 trigger, as specified in title 40 Code of Federal Regulations part 141, subpart Y, within a rolling twelve-month period unless the department has determined why the samples that caused the first level 1 treatment technique trigger were total coliform positive and has determined that the system has corrected the problem. b. Treatment technique violations. A system has a treatment technique violation when any of the following conditions occur: (1) A system exceeds a treatment technique trigger and then fails to conduct the required assessment or corrective actions within the required timeframe as specified in title 40 Code of Federal Regulations part 141, subpart Y. (2) A seasonal system fails to complete a state-approved start-up procedure before serving water to the public. c. E. coli maximum contaminant level violations. A system is in violation of the maximum contaminant level for E. coli when any of the following conditions occur: (1) A system has an E. coli-positive repeat sample following a total coliform-positive routine sample. (2) A system has a total coliform-positive repeat sample following an E. coli-positive routine sample. (3) A system fails to take all required repeat samples following an E. coli-positive routine sample. (4) A system fails to analyze for E. coli bacteria when any repeat sample tests positive for total coliform bacteria. d. Monitoring violations. A system incurs a monitoring violation if any of the following conditions occur: (1) A system fails to take every required routine sample in a compliance period. (2) A system fails to analyze for E. coli following a total coliform-positive routine sample. e. The department hereby identifies the following as the best technology, treatment techniques, or other means generally available for achieving compliance with the treatment technique triggers and E. coli maximum contaminant level: protection of wells from contamination by appropriate placement and construction; maintenance of a disinfection residual throughout the distribution system; proper maintenance of the distribution system including appropriate pipe replacement and repair procedures, cross-connection control programs, main flushing programs, proper operation and maintenance of storage tanks and reservoirs, and continual maintenance of a positive water pressure in all parts of the distribution system; filtration and disinfection or disinfection of surface water and disinfection of ground water using strong oxidants such as chlorine, chlorine dioxide, or ozone; and the development and implementation of a department-approved wellhead protection program. 6. Disinfectants. The maximum residual disinfectant levels for disinfectants are as follows: DISINFECTANT MAXIMUM RESIDUAL DISINFECTANT LEVEL IN MILLIGRAMS PER LITER Chlorine 4.0 as free chlorine Chloramines 4.0 as combined chlorine Chlorine dioxide 0.8 as chlorine dioxide The department identifies the following as the best technology, treatment techniques, or other means available for achieving compliance with the maximum residual disinfectant levels: control of treatment processes to reduce disinfectant demand and control of disinfection treatment processes to reduce disinfectant levels. 7. Disinfection byproducts. The maximum contaminant levels for total trihalomethanes, haloacetic acids five, bromate, and chlorite are as follows: DISINFECTION BYPRODUCT MAXIMUM CONTAMINANT LEVEL IN MILLIGRAMS PER LITER Total trihalomethanes 0.080 Haloacetic acids five 0.060 Bromate 0.010 Chlorite 1.0 The department identifies the following as the best technology, treatment techniques, or other means available for achieving compliance with the maximum contaminant level for total trihalomethanes and the maximum contaminant levels for haloacetic acids five, bromate, and chlorite: for total trihalomethanes and haloacetic acids five, enhanced coagulation, enhanced softening, or granular activated carbon ten with chlorine as the primary and residual disinfectant; for bromate, control of the ozone treatment process to reduce production of bromate; and for chlorite, control of treatment processes to reduce disinfectant demand and control of disinfection treatment processes to reduce disinfectant levels. All best available technology and compliance shall be prescribed by the department and set forth under title 40 Code of Federal Regulations part 141.64. 8. Disinfection byproduct precursors. The department hereby identifies enhanced coagulation and enhanced softening as treatment techniques to control the level of disinfection byproduct precursors in drinking water treatment and distribution systems. The treatment techniques apply only to subpart H community and nontransient noncommunity water systems that use conventional treatment. Such systems shall be deemed to be in compliance with the treatment techniques if the requirements set forth under title 40 Code of Federal Regulations part 141, subpart L, are met. 9. Confirmation sampling. The department may require confirmation samples and average confirmation sample results with initial sample results to determine compliance. At the discretion of the department, sample results due to obvious monitoring errors may be deleted prior to determining compliance.