R 325.10308b Best available technology.

Rule 308b. (1) The department identifies the following as the best technology, treatment technique, or other means generally available for achieving compliance with the MCL: (a) For organic contaminants in R 325.10604b, R325.10604d, and R 325.10604g the best available technologies, treatment techniques, or other means available for achieving compliance with the MCLs are granular activated carbon (GAC), packed tower aeration (PTA), or oxidation (OX), as listed in table 1 of this rule. Table 1 Best available technologies for organic contaminants Contaminant GAC PTA OX Alachlor x Aldicarb x Aldicarb sulfone x Aldicarb sulfoxide x Atrazine x Benzene x x Benzo(a)pyrene x Carbofuran x Carbon tetrachloride x x Chlordane x Dalapon x 2,4 D x Di (2 ethylhexyl)adipate x x Di (2 ethylhexyl)phthalate x Dibromochloropropane (DBCP) x x o Dichlorobenzene x x para Dichlorobenzene x x 1,2 Dichloroethane x x 1,1 Dichloroethylene x x cis 1,2 Dichloroethylene x x trans 1,2 Dichloroethylene x x Dichloromethane x 1,2 Dichloropropane x x Dinoseb x Contaminant GAC PTA OX Diquat x Endothall x Endrin x Ethylbenzene x x Ethylene Dibromide (EDB) x x Glyphosate x Heptachlor x Heptachlor epoxide x Hexachlorobenzene x Hexachlorocyclopentadiene x x Hexafluoropropylene oxide dimer acid (HFPO- DA) x1 Lindane x Methoxychlor x Monochlorobenzene x x Oxamyl (Vydate) x Pentachlorophenol x Perfluorobutanesulfonic acid (PFBS) x1 Perfluorohexanesulfonic acid (PFHxS) x1 Perfluorohexanoic acid (PFHxA) x1 Perfluorononanoic acid (PFNA) x1 Perfluorooctanesulfonic acid (PFOS) x1 Perfluorooctanoic acid (PFOA) x1 Picloram x Polychlorinated biphenyls(PCB) x Simazine x Styrene x x 2,3,7,8 TCDD (Dioxin) x Tetrachloroethylene x x Toluene x x Toxaphene x 2,4,5 TP (Silvex) x 1,2,4 Trichlorobenzene x x 1,1,1 Trichloroethane x x 1,1,2 Trichloroethane x x Trichloroethylene x x Vinyl chloride x Xylene x x 1Best available technology is GAC or an equally efficient technology. (b) For inorganic contaminants in R 325.10604c, the best available technologies, treatment techniques, or other means available for achieving compliance with the MCLs are listed in table 2 of this rule. The affordable technology, treatment technique, or other means available to supplies serving 10,000 or fewer people for achieving compliance with the maximum contaminant level for arsenic are listed in table 3 of this rule. Table 2 Best available technologies for inorganic contaminants Chemical name Best available technologies Antimony 2,7 Arsenic4 1,2, 5,6,7,9,115 Asbestos 2,3,8 Barium 5,6,7,9 Beryllium 1,2,5,6,7 Cadmium 2,5,6,7 Chromium 2,5,62,7 Cyanide 5,7,10 Mercury 21,4,61,7 1 Nickel 5,6,7 Nitrate 5,7,9 Nitrite 5,7 Selenium 1,23,6,7,9 Thallium 1,5 1Best available technology only if influent Hg concentrations are 10 µg/l or less. 2Best available technology for chromium III only. 3Best available technology for selenium IV only. 4BATs for Arsenic V. Pre-oxidation may be required to convert Arsenic III to Arsenic V. 5To obtain high removals, iron to arsenic ratio must be at least 20:1. Key to best available technologies in table: 1 = activated alumina 2 = coagulation/filtration (not BAT for supplies with fewer than 500 service connections) 3 = direct and diatomite filtration 4 = granular activated carbon 5 = ion exchange 6 = lime softening (not BAT for supplies than 500 service connections) 7 = reverse osmosis 8 = corrosion control 9 = electrodialysis 10 = alkaline chlorination (pH greater than or equal to 8.5) 11 = oxidation/filtration Table 3 Small supplies compliance technologies (SSCTs) for arsenic1 Small supply compliance technology Affordable for listed small supply categories.2 Activated alumina (centralized) All size categories. Small supply compliance technology Affordable for listed small supply categories.2 Activated alumina (point-of-use)3 All size categories. Coagulation/filtration 501-3,300, 3,301-10,000. Coagulation-assisted microfiltration 501-3,300, 3,301-10,000. Electrodialysis reversal 501-3,300, 3,301-10,000. Enhanced coagulation/filtration All size categories. Enhanced lime softening (pH more than 10.5) All size categories. Ion exchange All size categories. Lime softening 501-3,300, 3,301-10,000. Oxidation/filtration4 All size categories. Reverse osmosis (centralized) 501-3,300, 3,301-10,000. Reverse osmosis (point-of-use)3 All size categories. 1 SSCTs for Arsenic V. Pre-oxidation may be required to convert Arsenic III to Arsenic V. 2Three categories of small supplies are: (i) those serving 25 or more, but fewer than 501, (ii) those serving more than 500, but fewer than 3,301, and (iii) those serving more than 3,300, but fewer than 10,001. 3POU must not be used to obtain a variance. 4To obtain high removals, iron to arsenic ratio must be at least 20:1. (c) For radionuclide contaminants in R 325.10603, the best available technologies, treatment techniques, or other means available for achieving compliance with the MCLs are listed in table 4 for all size supplies. The affordable technology, treatment technique, or other means available for achieving compliance with the maximum contaminant level are listed in table 5 for supplies serving 10,000 or fewer people as categorized in table 6. Table 4 Best available technologies for radionuclide contaminants Contaminant Best available technologies. Combined radium 226 and radium 228 Ion exchange, reverse osmosis, lime softening. Uranium Ion exchange, reverse osmosis, lime softening, coagulation/filtration. Gross alpha particle activity (excluding radon and uranium) Reverse osmosis. Beta particle and proton radioactivity Ion exchange, reverse osmosis. Table 5 List of small supplies compliance technologies for radionuclides and limitations to use Unit Technologies Limitations (see footnotes) Operator skill level required * Raw water quality range and considerations. 1. Ion exchange (a) Intermediate All ground waters. 2. Reverse osmosis (RO) (b) Advanced Surface waters usually require pre- filtration. 3. Lime softening (c) Advanced All waters. 4. Green sand filtration (d) Basic 5. Co-precipitation and Barium sulfate (e) Intermediate to Advanced Ground waters with suitable water quality. 6. Electrodialysis/ electrodialysis reversal Not applicable Basic to intermediate All ground waters. 7. Pre-formed hydrous Manganese oxide filtration. (f) Intermediate All ground waters. 8. Activated alumina (a), (g) Advanced All ground waters; competing anion concentrations may affect regeneration frequency. 9. Enhanced coagulation/ filtration (h) Advanced Can treat a wide range of water qualities. * An operator with a basic skill level has minimal experience in the water treatment field and can perform the necessary system operation and monitoring if provided with proper instruction. The operator is capable of reading and following explicit directions. An operator with an intermediate skill level understands the principles of water treatment and has a knowledge of the regulatory framework. The operator is capable of making system changes in response to source water fluctuations. An operator with an advanced skill level possesses a thorough understanding of the principles of system operation. The operator is knowledgeable in water treatment and regulatory requirements. The operator may, however, have advanced knowledge of only the particular treatment technology. The operator seeks information, remains informed, and reliably interprets and responds to water fluctuations and system intricacies. Limitations Footnotes: Technologies for Radionuclides: a. The regeneration solution contains high concentrations of the contaminant ions. Disposal options must be carefully considered before choosing this technology. b. Reject water disposal options must be carefully considered before choosing this technology. c. The combination of variable source water quality and the complexity of the water chemistry involved may make this technology too complex for small surface water systems. d. Removal efficiencies may vary depending on water quality. e. This technology may be very limited in application to small systems. Since the process requires static mixing, detention basins, and filtration, it is most applicable to systems with sufficiently high sulfate levels that already have a suitable filtration treatment train in place. f. This technology is most applicable to small systems that already have filtration in place. g. Handling of chemicals required during regeneration and pH adjustment may be too difficult for small systems without an adequately trained operator. h. Assumes modification to a coagulation/filtration process already in place. Table 6 Compliance technologies by supply size category for radionuclide Requirements Contaminant Compliance technologies* for supply size categories (population served) 25-500 501-3,300 3,301 – 10,000 1. Combined radium 226 and radium 228 1, 2, 3, 4, 5, 6, 7 1, 2, 3, 4, 5, 6, 7 1, 2, 3, 4, 5, 6, 7 2. Gross alpha particle activity 2 2 2 3. Beta particle activity and photon activity 1, 2 1, 2 1, 2 4. Uranium 1, 8, 9 1, 2, 3, 8, 9 1, 2, 3, 8, 9 * Numbers correspond to those technologies listed in Table 5 of this rule. (2) The department shall require community water supplies and nontransient, noncommunity water supplies to employ a treatment method identified in subrule (1) of this rule as a condition for granting a variance, except as provided in subrule (3) of this rule. If, after the treatment method is installed in the system, the supply cannot meet the MCL, then the supply is eligible for a variance under this part and section 20 of the act, MCL 325.1020. (3) If a supply demonstrates through comprehensive engineering assessments, which may include pilot plant studies, that the treatment methods identified in subrule (1) of this rule may only achieve a de minimis reduction in contaminants, then the department may issue a schedule of compliance that requires the supply being granted the variance to examine other treatment methods as a condition of obtaining the variance. (4) If the department determines that a treatment method identified in subrule (3) of this rule is technically feasible, then the department may require the supply to use that treatment method in connection with a compliance schedule issued under section 20 of the act, MCL 325.1020. The department's determination must be based on studies by the supply and other relevant information. (5) The department may require a community or noncommunity supply to use point-of- use devices, point-of-entry devices, or other means as a condition of granting a variance or an exemption from the requirements of R 325.10603, R 325.10604b, R 325.10604c, R 325.10604d, or R325.10604g to avoid an unreasonable risk to health. The department may require a public water supply to use point-of-use devices or other means, but not point- of-entry devices, as a condition for granting an exemption from corrosion control treatment requirements for lead and copper in R 325.10604f(2) and (3) to avoid an unreasonable risk to health. The department may require a public water supply to use point-of-entry devices as a condition for granting an exemption from the source water and lead service line replacement requirements for lead and copper under R 325.10604f(4) and (5) to avoid an unreasonable risk to health, provided the supply demonstrates that the device will not cause an increased corrosion of lead and copper bearing materials located between the device and the tap that may increase contaminant levels at the tap. (6) Community or noncommunity water supplies that use point-of-use or point-of-entry devices under this rule shall meet the conditions in R 325.10313.