US Code

Public Law 119-102 (07/12/2026)

42 U.S.C. § 300j–13

Source water quality assessment

Section text and notes

(a)

Source water assessment

(1)

Guidance

section 300g–7(b) of this titleWithin 12 months after , after notice and comment, the Administrator shall publish guidance for States exercising primary enforcement responsibility for public water systems to carry out directly or through delegation (for the protection and benefit of public water systems and for the support of monitoring flexibility) a source water assessment program within the State’s boundaries. Each State adopting modifications to monitoring requirements pursuant to shall, prior to adopting such modifications, have an approved source water assessment program under this section and shall carry out the program either directly or through delegation.

(2)

Program requirements

A source water assessment program under this subsection shall—
(A)
delineate the boundaries of the assessment areas in such State from which one or more public water systems in the State receive supplies of drinking water, using all reasonably available hydrogeologic information on the sources of the supply of drinking water in the State and the water flow, recharge, and discharge and any other reliable information as the State deems necessary to adequately determine such areas; and
(B)
identify for contaminants regulated under this subchapter for which monitoring is required under this subchapter (or any unregulated contaminants selected by the State, in its discretion, which the State, for the purposes of this subsection, has determined may present a threat to public health), to the extent practical, the origins within each delineated area of such contaminants to determine the susceptibility of the public water systems in the delineated area to such contaminants.
(3)

Approval, implementation, and monitoring relief

section 300h–7(c) of this titlesection 300g–7(a) of this titlesection 300g–7(b) of this titleA State source water assessment program under this subsection shall be submitted to the Administrator within 18 months after the Administrator’s guidance is issued under this subsection and shall be deemed approved 9 months after the date of such submittal unless the Administrator disapproves the program as provided in . States shall begin implementation of the program immediately after its approval. The Administrator’s approval of a State program under this subsection shall include a timetable, established in consultation with the State, allowing not more than 2 years for completion after approval of the program. Public water systems seeking monitoring relief in addition to the interim relief provided under shall be eligible for monitoring relief, consistent with , upon completion of the assessment in the delineated source water assessment area or areas concerned.

(4)

Timetable

section 300j–12 of this titleThe timetable referred to in paragraph (3) shall take into consideration the availability to the State of funds under (relating to State loan funds) for assessments and other relevant factors. The Administrator may extend any timetable included in a State program approved under paragraph (3) to extend the period for completion by an additional 18 months.

(5)

Demonstration project

The Administrator shall, as soon as practicable, conduct a demonstration project, in consultation with other Federal agencies, to demonstrate the most effective and protective means of assessing and protecting source waters serving large metropolitan areas and located on Federal lands.

(6)

Use of other programs

To avoid duplication and to encourage efficiency, the program under this section may make use of any of the following:
(A)
Vulnerability assessments, sanitary surveys, and monitoring programs.
(B)
Delineations or assessments of ground water sources under a State wellhead protection program developed pursuant to this section.
(C)
section 136a(d) of title 7 Delineations or assessments of surface or ground water sources under a State pesticide management plan developed pursuant to the Pesticide and Ground Water State Management Plan Regulation (subparts I and J of part 152 of title 40, Code of Federal Regulations), promulgated under .
(D)
Delineations or assessments of surface water sources under a State watershed initiative or to satisfy the watershed criterion for determining if filtration is required under the Surface Water Treatment Rule (section 141.70 of title 40, Code of Federal Regulations).
(E)
33 U.S.C. 1251 Delineations or assessments of surface or ground water sources under programs or plans pursuant to the Federal Water Pollution Control Act [ et seq.].
(7)

Public availability

The State shall make the results of the source water assessments conducted under this subsection available to the public.

(b)

Approval and disapproval

section 300h–7(c) of this titleFor provisions relating to program approval and disapproval, see .

July 1, 1944, ch. 373 Pub. L. 104–182, title I, § 132(a)110 Stat. 1673 (, title XIV, § 1453, as added , , .)

Editorial Notes

References in Text

act June 30, 1948, ch. 758 Pub. L. 92–500, § 286 Stat. 816 section 1251 of Title 33The Federal Water Pollution Control Act, referred to in subsec. (a)(6)(E), is , as amended generally by , , , which is classified generally to chapter 26 (§ 1251 et seq.) of Title 33, Navigation and Navigable Waters. For complete classification of this Act to the Code, see Short Title note set out under and Tables.