[Code of Federal Regulations]

[Title 40, Volume 22]

[Revised as of July 1, 2005]

From the U.S. Government Printing Office via GPO Access

[CITE: 40CFR141.64]



[Page 437-438]

 

                   TITLE 40--PROTECTION OF ENVIRONMENT

 

         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)

 

PART 141_NATIONAL PRIMARY DRINKING WATER REGULATIONS--Table of Contents

 

     Subpart G_National Primary Drinking Water Regulations: Maximum 

       Contaminant Levels and Maximum Residual Disinfectant Levels

 

Sec. 141.64  Maximum contaminant levels for disinfection byproducts.



    (a) The maximum contaminant levels (MCLs) for disinfection 

byproducts are as follows:



[[Page 438]]







------------------------------------------------------------------------

                                                                MCL (mg/

                    Disinfection byproduct                         L)

------------------------------------------------------------------------

Total trihalomethanes (TTHM)..................................     0.080

Haloacetic acids (five) (HAA5)................................     0.060

Bromate.......................................................     0.010

Chlorite......................................................     1.0

------------------------------------------------------------------------



    (b) Compliance dates. (1) CWSs and NTNCWSs. Subpart H systems 

serving 10,000 or more persons must comply with this section 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 section beginning January 1, 2004.

    (2) A system that is installing GAC or membrane technology to comply 

with this section may apply to the State for an extension of up to 24 

months past the dates in paragraphs (b)(1) of this section, but not 

beyond December 31, 2003. In granting the extension, States must set a 

schedule for compliance and may specify any interim measures that the 

system must take. Failure to meet the schedule or interim treatment 

requirements constitutes a violation of a National Primary Drinking 

Water Regulation.

    (c) The Administrator, pursuant to Section 1412 of the Act, hereby 

identifies the following as the best technology, treatment techniques, 

or other means available for achieving compliance with the maximum 

contaminant levels for disinfection byproducts identified in paragraph 

(a) of this section:



------------------------------------------------------------------------

         Disinfection byproduct             Best available technology

------------------------------------------------------------------------

TTHM...................................  Enhanced coagulation or

                                          enhanced softening or GAC10,

                                          with chlorine as the primary

                                          and residual disinfectant

HAA5...................................  Enhanced coagulation or

                                          enhanced softening or GAC10,

                                          with chlorine as the primary

                                          and residual disinfectant.

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.

------------------------------------------------------------------------





[63 FR 69465, Dec. 16, 1998, as amended at 66 FR 3776, Jan. 16, 2001]