[Code of Federal Regulations]
[Title 40, Volume 22]
[Revised as of July 1, 2006]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR141.83]

[Page 440-442]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 141_NATIONAL PRIMARY DRINKING WATER REGULATIONS--Table of Contents
 
                  Subpart I_Control of Lead and Copper
 
Sec.  141.83  Source water treatment requirements.

    Systems shall complete the applicable source water monitoring and 
treatment requirements (described in the referenced portions of 
paragraph (b) of this section, and in Sec. Sec.  141.86, and 141.88) by 
the following deadlines.
    (a) Deadlines for completing source water treatment steps--(1) Step 
1: A system exceeding the lead or copper action level shall complete 
lead and copper source water monitoring (Sec.  141.88(b)) and make a 
treatment recommendation to the State (Sec.  141.83(b)(1)) within 6 
months after exceeding the lead or copper action level.
    (2) Step 2: The State shall make a determination regarding source 
water treatment (Sec.  141.83(b)(2)) within 6 months after submission of 
monitoring results under step 1.
    (3) Step 3: If the State requires installation of source water 
treatment, the system shall install the treatment (Sec.  141.83(b)(3)) 
within 24 months after completion of step 2.
    (4) Step 4: The system shall complete follow-up tap water monitoring 
(Sec.  141.86(d)(2) and source water monitoring (Sec.  141.88(c)) within 
36 months after completion of step 2.
    (5) Step 5: The State shall review the system's installation and 
operation of source water treatment and specify maximum permissible 
source water levels (Sec.  141.83(b)(4)) within 6 months after 
completion of step 4.
    (6) Step 6: The system shall operate in compliance with the State-
specified

[[Page 441]]

maximum permissible lead and copper source water levels (Sec.  
141.83(b)(4)) and continue source water monitoring (Sec.  141.88(d)).
    (b) Description of source water treatment requirements--(1) System 
treatment recommendation. Any system which exceeds the lead or copper 
action level shall recommend in writing to the State the installation 
and operation of one of the source water treatments listed in paragraph 
(b)(2) of this section. A system may recommend that no treatment be 
installed based upon a demonstration that source water treatment is not 
necessary to minimize lead and copper levels at users' taps.
    (2) State determination regarding source water treatment. The State 
shall complete an evaluation of the results of all source water samples 
submitted by the water system to determine whether source water 
treatment is necessary to minimize lead or copper levels in water 
delivered to users' taps. If the State determines that treatment is 
needed, the State shall either require installation and operation of the 
source water treatment recommended by the system (if any) or require the 
installation and operation of another source water treatment from among 
the following: Ion exchange, reverse osmosis, lime softening or 
coagulation/filtration. If the State requests additional information to 
aid in its review, the water system shall provide the information by the 
date specified by the State in its request. The State shall notify the 
system in writing of its determination and set forth the basis for its 
decision.
    (3) Installation of source water treatment. Each system shall 
properly install and operate the source water treatment designated by 
the State under paragraph (b)(2) of this section.
    (4) State review of source water treatment and specification of 
maximum permissible source water levels. The State shall review the 
source water samples taken by the water system both before and after the 
system installs source water treatment, and determine whether the system 
has properly installed and operated the source water treatment 
designated by the State. Based upon its review, the State shall 
designate the maximum permissible lead and copper concentrations for 
finished water entering the distribution system. Such levels shall 
reflect the contaminant removal capability of the treatment properly 
operated and maintained. The State shall notify the system in writing 
and explain the basis for its decision.
    (5) Continued operation and maintenance. Each water system shall 
maintain lead and copper levels below the maximum permissible 
concentrations designated by the State at each sampling point monitored 
in accordance with Sec.  141.88. The system is out of compliance with 
this paragraph if the level of lead or copper at any sampling point is 
greater than the maximum permissible concentration designated by the 
State.
    (6) Modification of State treatment decisions. Upon its own 
initiative or in response to a request by a water system or other 
interested party, a State may modify its determination of the source 
water treatment under paragraph (b)(2) of this section, or maximum 
permissible lead and copper concentrations for finished water entering 
the distribution system under paragraph (b)(4) of this section. A 
request for modification by a system or other interested party shall be 
in writing, explain why the modification is appropriate, and provide 
supporting documentation. The State may modify its determination where 
it concludes that such change is necessary to ensure that the system 
continues to minimize lead and copper concentrations in source water. A 
revised determination shall be made in writing, set forth the new 
treatment requirements, explain the basis for the State's decision, and 
provide an implementation schedule for completing the treatment 
modifications.
    (7) Treatment decisions by EPA in lieu of the State. Pursuant to the 
procedures in Sec.  142.19, the EPA Regional Administrator may review 
treatment determinations made by a State under paragraphs (b) (2), (4), 
or (6) of this section and issue Federal treatment determinations 
consistent with the requirements of those paragraphs where the 
Administrator finds that:
    (i) A State has failed to issue a treatment determination by the 
applicable deadlines contained in Sec.  141.83(a),

[[Page 442]]

    (ii) A state has abused its discretion in a substantial number of 
cases or in cases affecting a substantial population, or
    (iii) The technical aspects of a State's determination would be 
indefensible in an expected Federal enforcement action taken against a 
system.