Section 0400-45-01-.06 - MAXIMUM CONTAMINANT LEVELS(1) Inorganic Chemicals(a) The maximum contaminant level for fluoride applies to community water systems. The maximum contaminant levels for nitrate, nitrite and total nitrate and nitrite are applicable to both community water systems and non-community water systems. The maximum contaminant levels for the remaining inorganic chemicals apply only to community water systems and non-transient non-community systems.(b) The following are the maximum contaminant levels for inorganic chemicals: CONTAMINANT | LEVEL, MILLIGRAMS PER LITER |
1. Antimony | 0.006 |
2. Arsenic | 0.010 |
3. Asbestos | 7 million fibers/liter (longer than 10 microns) |
4. Beryllium | 0.004 |
5. Barium | 2.0 |
6. Cadmium | 0.005 |
7. Chromium | 0.1 |
8. Cyanide (as free cyanide) | 0.2 |
9. Fluoride | 4.0 |
10. Mercury | 0.002 |
11. Nickel | 0.1 |
12. Nitrate | 10.0 (as Nitrogen) |
13. Nitrite | 1.0 (as Nitrogen) |
14. Total nitrate and nitrate | 10.0 (as Nitrogen) |
15. Selenium | 0.05 |
16. Thallium | 0.002 |
(2) Organic Chemicals - The following are the maximum contaminant levels for organic chemicals. (a) The following maximum contaminant levels for organic contaminants apply to community water systems and non-transient non-community water systems. The maximum contaminant levels for volatile organic chemicals are given in paragraph (2) of Rule 0400-45-01-.25. CONTAMINANT | LEVEL MILLIGRAMS PER LITER |
1. Alachlor | 0.002 |
2. Atrazine | 0.003 |
3. Carbofuran | 0.04 |
4. Chlordane | 0.002 |
5. Dibromo chloropropane (DBCP) | 0.0002 |
6. 2,4 Dichlorophenoxyacetic acid | 0.07 |
7. Ethylene dibromide | 0.00005 |
8. Heptachlor | 0.0004 |
9. Heptachlor epoxide | 0.0002 |
10. Lindane | 0.0002 |
11. Methoxychlor | 0.04 |
12. Polychlorinated biphenyls | 0.0005 |
13. Toxaphene | 0.003 |
14. 2,4,5 Trichlorophenoxyproprionic acid | 0.05 |
15. Pentachlorophenol | 0.001 |
16. Benzo(a)pyrene | 0.0002 |
17. Dalapon | 0.2 |
18. Di(2-ethylhexyl) adipate | 0.4 |
19. Di(2-ethylhexyl)phthalate | 0.006 |
20. Dinoseb | 0.007 |
21. Diquat | 0.02 |
22. Endothall | 0.1 |
23. Glyphosate | 0.7 |
24. Hexachlorobenzene | 0.001 |
25. Hexachlorocyclopentadiene | 0.05 |
26. Oxamyl (Vydate) | 0.2 |
27. Picloram | 0.5 |
28. Simazine | 0.004 |
29. 2,3,7,8-TCDD (Dioxin) | 0.00000003 |
30. Endrin | 0.002 |
(3) Turbidity - The requirements of paragraph (3) of Rule 0400-45-01-.06 apply to filtered surface systems until June 29, 1993. The requirements in this paragraph apply to unfiltered systems that the Department has determined, in writing, must install filtration until June 29, 1993, or until filtration is installed, whichever is later. The maximum contaminant level for turbidity is applicable to public water systems using surface water source(s) in whole or in part. Furthermore, the maximum contaminant level for turbidity is applicable to those systems using ground water which are required to install turbidimeters pursuant to paragraph (11) of Rule 0400-45-01-.05. The maximum contaminant levels for turbidity in drinking water, measured at a representative entry point(s) to the distribution system are:
(a) One (1.0) turbidity unit, as determined by monthly average pursuant to Rule 0400-45-01-.08.(b) Two (2.0) turbidity units based on an average for two consecutive days pursuant to Rule 0400-45-01-.08. To meet the maximum contaminant level for turbidity, a public water system must meet both subparagraphs (a) and (b) of this paragraph.
(4) Microbiological - The maximum contaminant levels for microbiologicals are applicable to both community water systems and non-community water systems. (a) Until March 31, 2016, the total coliform maximum contaminant level (MCL) is based on the presence or absence of total coliforms in a sample, rather than coliform density. Beginning April 1, 2016, the MCL for total coliform shall no longer be in effect. The number of total coliform positive samples shall not exceed any of the following:
1. For a system which collects at least 40 samples per month, if no more than 5.0 percent of the samples collected during a month are total coliform-positive, the system is in compliance with the MCL for total coliforms.2. For a system which collects fewer than 40 samples/month, if no more than one sample collected during a month is total coliform-positive, the system is in compliance with the MCL for total coliforms.3. A public water system which has exceeded the MCL for total coliforms must report the violation to the Department no later than the end of the next business day after it learns of the violation and notify the public in accordance with the schedule of Rule 0400-45-01-.19 using the language specified in Rule 0400-45-01-.19.4. A public water system which has failed to comply with the coliform monitoring requirements, including a sanitary survey requirement must report the monitoring violation to the Department within ten (10) days after the system discovers the violation and notify the public in accordance with Rule 0400-45-01-.19.(b) Until March 31, 2016, any fecal coliform-positive repeat sample or E. coli-positive repeat sample, or any total coliform-positive repeat sample following a fecal coliform-positive or E. coli-positive routine sample, constitutes a violation of the MCL for total coliforms. For purposes of the public notification requirements in Rule 0400-45-01-.19, this is a violation that may pose an acute risk to health.(c) Fecal coliforms/Escherichia coli (E. coli) testing 1. If any routine or repeat sample is total coliform-positive, the system must analyze that total coliform-positive culture medium to determine if fecal coliforms are present, except that the system may test for E. coli in lieu of fecal coliforms. If fecal coliforms or E. coli are present, the system must notify the Department by the end of the day when the system is notified of the test result, unless the system is notified of the result after the Department office is closed, in which case the system must notify the Department before the end of the next business day.2. The Department has the discretion to allow a public water system, on a case-by-case basis, to forgo fecal coliform or E. coli testing on a total coliform-positive sample if that system assumes that the total coliform-positive sample is fecal coliform-positive or E. coli-positive. Accordingly, the system must notify the Department as specified in part 1 of this subparagraph and the provisions of subparagraph (b) of this paragraph apply.(d) A public water system must determine compliance with the MCL for total coliforms in subparagraph (a) and (b) of this paragraph for each month in which it is required to monitor for total coliforms.(e) No variance or exemptions from the maximum contaminant level for total coliforms are permitted.(f) Maximum contaminant level goals for microbiological contaminants. 1. MCLGs for the following contaminants are as indicated: Contaminant | MCLG |
(i) Giardia lamblia | zero |
(ii) Viruses | zero |
(iii) Legionella | zero |
(iv) Total coliforms (including fecal coliforms andEscherichia coli) | zero |
(v) Cryptosporidium | zero |
(vi) Escherichia coli (E. coli) | zero |
2. The MCLG identified in subpart 1(iv) of this subparagraph is no longer applicable beginning April 1, 2016.(g) Beginning April 1, 2016, a system is in compliance with the MCL for E. coli for samples taken under the provisions of Rule 0400-45-01-.41 unless any of the conditions identified in parts 1 through 4 of this subparagraph occur. For purposes of the public notification requirements in Rule 0400-45-01-.19, violation of the MCL may pose an acute risk to health.1. The system has an E. coli-positive repeat sample following a total coliform positive routine sample.2. The system has a total coliform positive repeat sample following an E. coli-positive routine sample.3. The system fails to take all required repeat samples following an E. coli-positive routine sample.4. The system fails to test for E. coli when any repeat sample tests positive for total coliform.(h) Until March 31, 2016, a public water system must determine compliance with the MCL for total coliforms in subparagraphs (a) and (b) of this paragraph for each month in which it is required to monitor for total coliforms. Beginning April 1, 2016, a public water system must determine compliance with the MCL for E. coli in subparagraph (g) of this paragraph for each month in which it is required to monitor for total coliforms.(i) The EPA Administrator, pursuant to section 1412 of the Federal Safe Drinking Water Act, hereby identifies the following as the best technology, treatment techniques, or other means available for achieving compliance with the maximum contaminant level for total coliforms in subparagraphs (a) and (b) of this paragraph and for achieving compliance with the maximum contaminant level for E. coli in subparagraph (g) of this paragraph: 1. Protection of wells from fecal contamination by appropriate placement and construction;2. Maintenance of a disinfectant residual throughout the distribution system;3. Proper maintenance of the distribution system including appropriate pipe replacement and repair procedures, main flushing programs, proper operation and maintenance of storage tanks and reservoirs, cross connection control, and continual maintenance of positive water pressure in all parts of the distribution system;4. Filtration and/or disinfection of surface water, as described in Rules 0400-45-01-.17, 0400-45-01-.31 and 0400-45-01-.39, or disinfection of ground water, as described in Rule 0400-45-01-.40, using strong oxidants such as chlorine, chlorine dioxide, or ozone; and5. For systems using ground water, compliance with the requirements of an EPA-approved State Wellhead Protection Program developed and implemented under section 1428 of the Federal Safe Drinking Water Act.(j) The EPA Administrator, pursuant to section 1412 of the Federal Safe Drinking Water Act, hereby identifies the technology, treatment techniques, or other means available identified in subparagraph (i) of this paragraph as affordable technology, treatment techniques, or other means available to systems serving 10,000 or fewer people for achieving compliance with the maximum contaminant level for total coliforms in subparagraphs (a) and (b) of this paragraph and for achieving compliance with the maximum contaminant level for E. coli in subparagraph (g) of this paragraph. (5) Radionuclides- (a) The following maximum contaminant levels for radium-226, radium-228, and gross alpha particle radioactivity are applicable to all community water systems:1. Combined radium-226 and radium-228: The maximum contaminant level for combined radium-226 and radium-228 is 5 pCi/L. The combined radium-226 and radium-228 value is determined by the addition of the results of the analysis for radium-226 and the analysis for radium-228.2. Gross alpha particle activity (including radium-226 but excluding radon and uranium): The maximum contaminant level for gross alpha particle activity (including radium-226 but excluding radon and uranium) is 15 pCi/L.(b) Maximum contaminant levels for beta particle and photon radioactivity from man- made radionuclides in community water systems shall be as follows:1. The average annual concentration of beta particle and photon radioactivity from man-made radionuclides in drinking water shall not produce an annual dose equivalent to the total body or any internal organ greater than four (4) millirem/year.2. Except for the radionuclides listed in Table A, the concentration of man-made radionuclides causing four (4) mrem total body or organ dose equivalents shall be calculated on the basis of a two (2) liter per day drinking water intake using the 168 hour data listed in "Maximum Permissible Body Burdens and Maximum Permissible Concentration of Radionuclides in Air or Water for Occupational Exposure," NBS Handbook 69 as amended August, 1963, U.S. Department of Commerce. If two or more radionuclides are present, the sum of their annual dose equivalent to the total body or to any organ shall not exceed four (4) millirem/year. Table A
Average Annual Concentrations Assumed to Produce a Total Body or Organ Dose of a 4 mrem/yr.
Radionuclide | Critical Organ | pCi per Liter |
Tritium Strontium-90 | Total Body Bone Marrow | 20,000 8 |
(c) MCL for uranium. The maximum contaminant level for uranium is 30 micrograms per liter.(d) Compliance dates. 1. Compliance dates for combined radium-226 and -228, gross alpha particle activity, gross beta particle and photon radioactivity, and uranium: Community water systems must comply with the MCLs listed in subparagraphs (a), (b), and (c) of this paragraph, beginning December 8, 2003 and compliance shall be determined in accordance with the requirements of Rule 0400-45-01-.11. Compliance with reporting requirements for the radionuclides under Appendix A to Consumer Confidence Reports (Rule 0400-45-01-.35 ) and Appendices A and B to Public Notification (Rule 0400-45-01-.19 ) is required on December 8, 2003.(e) Best Available Technologies The Department hereby identifies as indicated in the following table the best technology available for achieving compliance with the maximum contaminant levels for combined radium-226 and -228, uranium, gross alpha particle activity, and beta particle and photon radioactivity.
Table B
BAT for Combined Radium-226 and Radium-228, Uranium, Gross Alpha Particle Activity , and Beta Particle and Photon Radioactivity
Contaminant | BAT |
1. Combined radium-226 and radium-228 | Ion exchange, reverse osmosis, lime softening. |
2. Uranium | Ion exchange, reverse osmosis, lime softening, coagulation/filtration |
3. Gross alpha particle activity (excluding Radon and Uranium) | Reverse osmosis |
4. Beta particle and photon radioactivity | Ion exchange and reverse osmosis |
(f) No variance or exemption for compliance with the MCLs listed in paragraph (5) of this rule are allowed.(g) Small systems compliance technologies list for radionuclides. Table C
List of Small Systems Compliance Technologies for Radionuclides and Limitations to Use
Unit Technologies | Limitations (see footnotes) | Operator skill level required1 | Raw water quality range and considerations.1 |
1. Ion Exchange (IE) | (a) | Intermediate | All ground waters. |
2. Point of use (POU2) IE | (b) | Basic | All ground waters. |
3. Reverse osmosis (RO) | (c) | Advanced | Surface waters usually require pre-filtration. |
4. POU2RO | (b) | Basic | Surface waters usually require pre-filtration. |
5. Lime softening | (d) | Advanced | All waters. |
6. Green sand filtration | (e) | Basic | |
7. Co-precipitation with Barium Sulfate | (f) | Intermediate to Advanced | Ground waters with suitable water quality. |
8. Electrodialysis/ electrodialysis reversal | | Basic to imtermediate | All ground waters. |
9. Pre-formed hydrous Manganese oxide filtration | (g) | Intermediate | All ground waters. |
10. Activated alumia | (a) (h) | Advanced | All ground waters; competing anion concentrations may affect regeneration frequency. |
11. Enhanced coagulation/filtration | (i) | Advanced | Can treat a wide range of water qualities |
1 National Research Council (NRC). Safe Water from Every Tap: Improving Water Service to Small Communities. National Academy Press. Washington, D.C. 1997.
2 A POU, or "point-of-use" technology is a treatment device installed at a single tap used for the purpose of reducing contaminants in drinking water at that one tap. POU devices are typically installed at the kitchen tap. See the April 21, 2000 NODA for more details.
Limitations Footnotes: Technologies for Radionuclides:
(a) The regeneration solution contains high concentrations of the contaminant ions. Disposal options should be carefully considered before choosing this technology.(b) When POU devices are used for compliance, programs for long-term operation, maintenance, and monitoring must be provided by water utility to ensure proper performance.(c) Reject water disposal options should be carefully considered before choosing this technology. See other RO limitations described in the SWTR Compliance Technologies Table.(d) 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.(e) Removal efficiencies can vary depending on water quality.(f) 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.(g) This technology is most applicable to small systems that already have filtration in place.(h) Handling of chemicals required during regeneration and pH adjustment may be too difficult for small systems without an adequately trained operator.(i) Assumes modification to a coagulation/filtration process already in place. Table D
Compliance Technologies by System Size Category for Radionuclide NPDWR's
Contaminant | Compliance Technologies1 for system size categories (population served) |
| 25-500 | 501-3,300 | 3301-10,000 |
1. Combined radium-226 and radium-228 | 1,2,3,4,5,6,7,8,9 | 1,2,3,4,5,6,7,8,9 | 1,2,3,4,5,6,7,8,9 |
2. Gross alpha particle activity | 3.4 | 3.4 | 3,4 |
3. Beta particle activity and photon activity | 1,2,3,4 | 1,2,3,4 | 1,2,3,4 |
4. Uranium | 1,2,4,10,11 | 1,2,3,4,5,10,11 | 1,2,3,4,5,10,11 |
Note:1 Numbers correspond to those technologies found listed in Table C.
(6) Disinfectant Residuals and Disinfectant Byproducts(a) Bromate and chlorite. The maximum contaminant levels (MCLs) for bromate and chlorite are as follows: Disinfection by-product | MCL (mg/L) |
Bromate | 0 .010 |
Chlorite | 1 .0 |
1. Compliance dates for CWSs and NTNCWSs. Subpart H systems serving 10,000 or more persons must comply with this subparagraph beginning January 1, 2002. Subpart H systems serving fewer than 10,000 persons and systems using only ground water not under the direct influence of surface water must comply with this subparagraph beginning January 1, 2004.2. The Administrator, pursuant to section 1412 of the Federal Safe Drinking Water Act, hereby identifies the following as the best technology, treatment techniques, or other means available for achieving compliance with the maximum contaminant levels for bromate and chlorite identified in this subparagraph: Disinfection by-product | Best available technology |
Bromate | Control of ozone treatment process to reduce production of bromate |
Chlorite | Control of treatment processes to reduce disinfectant demand and control of disinfection treatment processes to reduce disinfectant levels |
(b) TTHM and HAA5. 1. Running Annual Average compliance (Rule 0400-45-01-.36 ) (i) Compliance dates. Subpart H systems serving 10,000 or more persons must comply with this part beginning January 1, 2002. Subpart H systems serving fewer than 10,000 persons and systems using only ground water not under the direct influence of surface water must comply with this this part beginning January 1, 2004. All systems must comply with these MCLs until the date specified for Locational Running Annual Average (Stage 2 Disinfection Byproducts Requirements (LRAA)) compliance in Rule 0400-45-01-.38. Disinfection by-product | MCL (mg/L) |
Total trihalomethanes (TTHM) | 0.080 |
Haloacetic acids (five) (HAA5) | 0.060 |
(ii) The Administrator, pursuant to section 1412 of the Federal Safe Drinking Water Act, hereby identifies the following as the best technology, treatment techniques, or other means available for achieving compliance with the maximum contaminant levels for TTHM and HAA5 identified in this part. Disinfection by-product | Best available technology |
Total trihalomethanes (TTHM) and Haloacetic acids (five) (HAA5) | Enhanced coagulation or enhanced softening or GAC10, with chlorine as the primary and residual disinfectant |
2. LRAA compliance (Rule 0400-45-01-.38 ) (i) Compliance dates. The Stage 2 Disinfection Byproducts Requirements (LRAA) MCLs for TTHM and HAA5 must be complied with as a locational running annual average (LRAA) at each monitoring location beginning the date specified for Stage 2 Disinfection Byproducts Requirements (LRAA) compliance in subparagraph (1)(c) of Rule 0400-45-01-.38. Disinfection by-product | MCL (mg/L) |
Total trihalomethanes (TTHM) | 0.080 |
Haloacetic acids (five) (HAA5) | 0.060 |
(ii) The Administrator, pursuant to section 1412 of the Federal Safe Drinking Water Act, hereby identifies the following as the best technology, treatment techniques, or other means available for achieving compliance with the maximum contaminant levels for TTHM and HAA5 identified in this part for all systems that disinfect their source water: Disinfection by-product | Best available technology |
Total trihalomethanes (TTHM) and Haloacetic acids (five) (HAA5) | Enhanced coagulation or enhanced softening or GAC10; nanofiltration and with a molecular weight cutoff of equal to or less than 1000 Daltons; or GAC20 |
(iii) The Administrator, pursuant to section 1412 of the Federal Safe Drinking Water Act, hereby identifies the following as the best technology, treatment techniques, or other means available for achieving compliance with the maximum contaminant levels for TTHM and HAA5 identified in this part for consecutive systems and applies only to the disinfected water that consecutive systems buy or otherwise receive: Disinfection by-product | Best available technology |
Total trihalomethanes (TTHM) and Haloacetic acids (five) - (HAA5). | Systems serving 10,000 or more: Improved distribution system and storage tank management to reduce residence time, plus the use of chloramines for disinfectant residual maintenance. Systems serving [LESS THAN] 10,000: Improved distribution system and storage tank management to reduce residence time. |
(c) Maximum residual disinfectant levels. 1. Maximum residual disinfectant levels (MRDLs) are as follows: Disinfectant residual | MRDL (mg/L) |
Chlorine ........................ ......... | 4.0 (as Cl2). |
Chloramines................................. | 4.0 (as Cl2). |
Chlorine dioxide.......................... | 0.8 (as ClO2). |
(d) Compliance dates. 1. CWSs and NTNCWSs. Subpart H systems serving 10,000 or more persons must comply with MRDLs beginning January 1, 2002. Subpart H systems serving fewer than 10,000 persons and systems using only ground water not under the direct influence of surface water must comply with MRDLs beginning January 1, 2004.2. Transient NCWSs. Subpart H systems serving 10,000 or more persons and using chlorine dioxide as a disinfectant or oxidant must comply with the chlorine dioxide MRDL beginning January 1, 2002. Subpart H systems serving fewer than 10,000 persons and using chlorine dioxide as a disinfectant or oxidant and systems using only ground water not under the direct influence of surface water and using chlorine dioxide as a disinfectant or oxidant must comply with the chlorine dioxide MRDL beginning January 1, 2004.(e) Best Available Control Technology1. The following are identified as the best technology, treatment technology or other means available for achieving compliance with the maximum residual disinfectant level:(i) Control of the treatment processes to reduce disinfectant demand and control of disinfection treatment processes to reduce disinfectant levels.Tenn. Comp. R. & Regs. 0400-45-01-.06
Original rule filed August 1, 2012; effective October 30, 2012. Rule was previously numbered 1200-05-01. Amendments and new rules filed November 24, 2015; effective February 22, 2016. Amendments filed March 7, 2016; effective 6/5/2016.Authority: T.C.A. §§ 68-221-701 et seq. and 4-5-201 et seq.