---
kind: "section"
citation: "15 U.S.C. § 8911"
title: "15"
title_heading: "Commerce and Trade"
number: "8911"
heading: "Monitoring and detection"
release: "119-102"
date: "2026-07-12"
url: "https://uscodex.org/usc/15/8911"
units:
  - "Chapter 115 — Perfluoroalkyl and Polyfluoroalkyl Substances and Emerging Contaminants"
  - "Subchapter I — Drinking Water"
---

# §8911. Monitoring and detection

- (a) **Monitoring program for unregulated contaminants—**
  - (1) **In general—** The [Administrator](/usc/15/636e.md?p=1) shall include each substance described in [paragraph (2)](#a-2) in the fifth publication of the list of unregulated contaminants to be monitored under [section 300j–4(a)(2)(B)(i) of title 42](/usc/42/300j–4.md?p=a-2-B-i).
  - (2) **Substances described—** The substances referred to in [paragraph (1)](#a-1) are perfluoroalkyl and polyfluoroalkyl substances and classes of perfluoroalkyl and polyfluoroalkyl substances—
    - (A) for which a method to measure the level in drinking water has been validated by the [Administrator](/usc/15/636e.md?p=1); and
    - (B) that are not subject to a national primary drinking water regulation.
  - (3) **Exception—** The perfluoroalkyl and polyfluoroalkyl substances and classes of perfluoroalkyl and polyfluoroalkyl substances included in the list of unregulated contaminants to be monitored under [section 300j–4(a)(2)(B)(i) of title 42](/usc/42/300j–4.md?p=a-2-B-i) under [paragraph (1)](#a-1) shall not count towards the limit of 30 unregulated contaminants to be monitored by public water systems under that section.
- (b) **Applicability—**
  - (1) **In general—** The [Administrator](/usc/15/636e.md?p=1) shall—
    - (A) require public water systems serving more than 10,000 [persons](/usc/15/7a.md?p=6) to monitor for the substances described in [subsection (a)(2)](#a-2);
    - (B) subject to [paragraph (2)](#b-2) and the availability of appropriations, require public water systems serving not fewer than 3,300 and not more than 10,000 [persons](/usc/15/7a.md?p=6) to monitor for the substances described in [subsection (a)(2)](#a-2); and
    - (C) subject to [paragraph (2)](#b-2) and the availability of appropriations, ensure that only a representative sample of public water systems serving fewer than 3,300 [persons](/usc/15/7a.md?p=6) are required to monitor for the substances described in [subsection (a)(2)](#a-2).
  - (2) **Requirement—** If the [Administrator](/usc/15/636e.md?p=1) determines that there is not sufficient laboratory capacity to carry out the monitoring required under subparagraphs [(B)](#b-1-B) and [(C)](#b-1-C) of paragraph (1), the [Administrator](/usc/15/636e.md?p=1) may waive the monitoring requirements in those subparagraphs.
  - (3) **Funds—** The [Administrator](/usc/15/636e.md?p=1) shall pay the reasonable cost of such testing and laboratory analysis as is necessary to carry out the monitoring required under subparagraphs [(B)](#b-1-B) and [(C)](#b-1-C) of paragraph (1) using—
    - (A) funds made available pursuant to subsection (a)(2)(H) or subsection (j)(5) of [section 300j–4 of title 42](/usc/42/300j–4.md); or
    - (B) any other funds made available for that purpose.

## Source credit

(Pub. L. 116–92, div. F, title LXXIII, § 7311, Dec. 20, 2019, 133 Stat. 2276.)