[Code of Federal Regulations]
[Title 40, Volume 19]
[Revised as of July 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR141.22]

[Page 352-353]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 141--NATIONAL PRIMARY DRINKING WATER REGULATIONS--Table of Contents
 
            Subpart C--Monitoring and Analytical Requirements
 
Sec. 141.22  Turbidity sampling and analytical requirements.

    The requirements in this section apply to unfiltered systems until 
December 30, 1991, unless the State has determined prior to that date, 
in writing pursuant to section 1412(b)(7)(iii), that filtration is 
required. The requirements in this section apply to filtered systems 
until June 29, 1993. The requirements in this section apply to 
unfiltered systems that the State has determined, in writing pursuant to 
section 1412(b)(7)(C)(iii), must install filtration, until June 29, 
1993, or until filtration is installed, whichever is later.
    (a) Samples shall be taken by suppliers of water for both community 
and non-community water systems at a representative entry point(s) to 
the water distribution system at least once per day, for the purposes of 
making turbidity measurements to determine compliance with Sec. 141.13. 
If the State determines that a reduced sampling frequency in a non-
community will not pose a risk to public health, it can reduce the 
required sampling frequency. The option of reducing the turbidity 
frequency shall be permitted only in those public water systems that 
practice disinfection and which maintain an active residual disinfectant 
in the distribution system, and in those cases where the State has 
indicated in writing that no unreasonable risk to health existed under 
the circumstances of this option. Turbidity measurements shall be made 
as directed in Sec. 141.74(a)(1).
    (b) If the result of a turbidity analysis indicates that the maximum 
allowable limit has been exceeded, the sampling and measurement shall be 
confirmed by resampling as soon as practicable and preferably within one 
hour. If the repeat sample confirms that the maximum allowable limit has 
been exceeded, the supplier of water

[[Page 353]]

shall report to the State within 48 hours. The repeat sample shall be 
the sample used for the purpose of calculating the monthly average. If 
the monthly average of the daily samples exceeds the maximum allowable 
limit, or if the average of two samples taken on consecutive days 
exceeds 5 TU, the supplier of water shall report to the State and notify 
the public as directed in Secs. 141.31 and subpart Q.
    (c) Sampling for non-community water systems shall begin within two 
years after the effective date of this part.
    (d) The requirements of this Sec. 141.22 shall apply only to public 
water systems which use water obtained in whole or in part from surface 
sources.
    (e) The State has the authority to determine compliance or initiate 
enforcement action based upon analytical results or other information 
compiled by their sanctioned representatives and agencies.

[40 FR 59570, Dec. 24, 1975, as amended at 45 FR 57344, Aug. 27, 1980; 
47 FR 8998, Mar. 3, 1982; 47 FR 10998, Mar. 12, 1982; 54 FR 27527, June 
29, 1989; 59 FR 62466, Dec. 5, 1994; 65 FR 26022, May 4, 2000]