[Code of Federal Regulations]
[Title 40, Volume 22]
[Revised as of July 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR141.70]

[Page 445-446]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 141_NATIONAL PRIMARY DRINKING WATER REGULATIONS--Table of Contents
 
                  Subpart H_Filtration and Disinfection
 
Sec. 141.70  General requirements.

    Source: 54 FR 27527, June 29, 1989, unless otherwise noted.


    (a) The requirements of this subpart H constitute national primary 
drinking water regulations. These regulations establish criteria under 
which filtration is required as a treatment technique for public water 
systems supplied by a surface water source and public water systems 
supplied by a ground water source under the direct influence of surface 
water. In addition, these regulations establish treatment technique 
requirements in lieu of maximum contaminant levels for the following 
contaminants: Giardia lamblia, viruses, heterotrophic plate count 
bacteria, Legionella, and turbidity. Each public water system with a 
surface water source or a ground water source under the direct influence 
of surface water must provide treatment of that source water that 
complies with these treatment technique requirements. The treatment 
technique requirements consist of installing and properly operating 
water treatment processes which reliably achieve:
    (1) At least 99.9 percent (3-log) removal and/or inactivation of 
Giardia lamblia cysts between a point where the raw water is not subject 
to recontamination by surface water runoff and a point downstream before 
or at the first customer; and
    (2) At least 99.99 percent (4-log) removal and/or inactivation of 
viruses between a point where the raw water is not subject to 
recontamination by surface water runoff and a point downstream before or 
at the first customer.
    (b) A public water system using a surface water source or a ground 
water source under the direct influence of surface water is considered 
to be in compliance with the requirements of paragraph (a) of this 
section if:
    (1) It meets the requirements for avoiding filtration in Sec. 
141.71 and the disinfection requirements in Sec. 141.72(a); or
    (2) It meets the filtration requirements in Sec. 141.73 and the 
disinfection requirements in Sec. 141.72(b).
    (c) Each public water system using a surface water source or a 
ground water source under the direct influence of surface water must be 
operated by qualified personnel who meet the requirements specified by 
the State.
    (d) Additional requirements for systems serving at least 10,000 
people. In addition to complying with requirements in this subpart, 
systems serving at least 10,000 people must also comply with the 
requirements in subpart P of this part.
    (e) Additional requirements for systems serving fewer than 10,000 
people. In addition to complying with requirements in this subpart, 
systems serving fewer than 10,000 people must also comply

[[Page 446]]

with the requirements in subpart T of this part.

[54 FR 27527, June 29, 1989, as amended at 63 FR 69516, Dec. 16, 1998; 
67 FR 1836, Jan. 14, 2002]