---
kind: "section"
citation: "42 U.S.C. § 7651k"
title: "42"
title_heading: "The Public Health and Welfare"
number: "7651k"
heading: "Monitoring, reporting, and recordkeeping requirements"
release: "119-102"
date: "2026-07-12"
url: "https://uscodex.org/usc/42/7651k"
units:
  - "Chapter 85 — Air Pollution Prevention and Control"
  - "Subchapter IV–A — Acid Deposition Control"
---

# §7651k. Monitoring, reporting, and recordkeeping requirements

- (a) **Applicability—** The [owner](/usc/42/13641.md?p=4) and operator of any source subject to this subchapter shall be required to install and operate CEMS on each [affected unit](/usc/42/7651a.md?p=2) at the source, and to quality assure the data for sulfur dioxide, nitrogen oxides, opacity and volumetric flow at each such [unit](/usc/42/7651a.md?p=15). The [Administrator](/usc/42/7602.md?p=a) shall, by regulations issued not later than eighteen months after November 15, 1990, specify the requirements for CEMS, for any alternative monitoring system that is demonstrated as providing information with the same precision, reliability, accessibility, and timeliness as that provided by CEMS, and for recordkeeping and reporting of information from such systems. Such regulations may include limitations or the use of alternative compliance methods by [units](/usc/42/7651a.md?p=15) equipped with an alternative monitoring system as may be necessary to preserve the orderly functioning of the [allowance](/usc/42/7651a.md?p=3) system, and which will ensure the emissions reductions contemplated by this subchapter. Where 2 or more [units](/usc/42/7651a.md?p=15) utilize a single stack, a separate CEMS shall not be required for each [unit](/usc/42/7651a.md?p=15), and for such [units](/usc/42/7651a.md?p=15) the regulations shall require that the [owner](/usc/42/13641.md?p=4) or operator collect sufficient information to permit reliable compliance determinations for each such [unit](/usc/42/7651a.md?p=15).
- (b) **First phase requirements—** Not later than thirty-six months after November 15, 1990, the [owner](/usc/42/13641.md?p=4) or operator of each [affected unit](/usc/42/7651a.md?p=2) under [section 7651c of this title](/usc/42/7651c.md), including, but not limited to, [units](/usc/42/7651a.md?p=15) that become [affected units](/usc/42/7651a.md?p=2) pursuant to subsections [(b)](#b) and [(c)](#c) and eligible [units](/usc/42/7651a.md?p=15) under [subsection (d)](#d), shall install and operate CEMS, quality assure the data, and keep records and reports in accordance with the regulations issued under [subsection (a)](#a).
- (c) **Second phase requirements—** Not later than January 1, 1995, the [owner](/usc/42/13641.md?p=4) or operator of each [affected unit](/usc/42/7651a.md?p=2) that has not previously met the requirements of subsections [(a)](#a) and [(b)](#b) shall install and operate CEMS, quality assure the data, and keep records and reports in accordance with the regulations issued under [subsection (a)](#a). Upon commencement of commercial operation of each new [utility unit](/usc/42/7651a.md?p=17-A), the [unit](/usc/42/7651a.md?p=15) shall comply with the requirements of [subsection (a)](#a).
- (d) **Unavailability of emissions data—** If CEMS data or data from an alternative monitoring system approved by the [Administrator](/usc/42/7602.md?p=a) under [subsection (a)](#a) is not available for any [affected unit](/usc/42/7651a.md?p=2) during any period of a calendar year in which such data is required under this subchapter, and the [owner](/usc/42/13641.md?p=4) or operator cannot provide information, satisfactory to the [Administrator](/usc/42/7602.md?p=a), on emissions during that period, the [Administrator](/usc/42/7602.md?p=a) shall deem the [unit](/usc/42/7651a.md?p=15) to be operating in an uncontrolled manner during the entire period for which the data was not available and shall, by regulation which shall be issued not later than eighteen months after November 15, 1990, prescribe means to calculate emissions for that period. The [owner](/usc/42/13641.md?p=4) or operator shall be liable for excess emissions fees and offsets under [section 7651j of this title](/usc/42/7651j.md) in accordance with such regulations. Any fee due and payable under this subsection shall not diminish the liability of the [unit](/usc/42/7651a.md?p=15)’s [owner](/usc/42/13641.md?p=4) or operator for any fine, penalty, fee or assessment against the [unit](/usc/42/7651a.md?p=15) for the same [violation](/usc/42/2000e–16a.md?p=c) under any other section of this chapter.
- (e) **Prohibition—** It shall be unlawful for the [owner](/usc/42/13641.md?p=4) or operator of any source subject to this subchapter to operate a source without complying with the requirements of this section, and any regulations implementing this section.

## Source credit

(July 14, 1955, ch. 360, title IV, § 412, as added Pub. L. 101–549, title IV, § 401, Nov. 15, 1990, 104 Stat. 2624.)

## Notes

### Statutory Notes and Related Subsidiaries

### Information Gathering on Greenhouse Gases Contributing to Global Climate Change

Pub. L. 101–549, title VIII, § 821, Nov. 15, 1990, 104 Stat. 2699, provided that: Monitoring.—The Administrator of the Environmental Protection Agency shall promulgate regulations within 18 months after the enactment of the Clean Air Act Amendments of 1990 [Nov. 15, 1990] to require that all affected sources subject to title V of the Clean Air Act [probably means title IV of the Clean Air Act as added by Pub. L. 101–549, which is classified to section 7651 et seq. of this title] shall also monitor carbon dioxide emissions according to the same timetable as in section 511(b) and (c) [probably means section 412(b) and (c) of the Clean Air Act, which is classified to section 7651k(b) and (c) of this title]. The regulations shall require that such data be reported to the Administrator. The provisions of section 511(e) of title V of the Clean Air Act [probably means section 412(e) of title IV of the Clean Air Act, which is classified to section 7651k(e) of this title] shall apply for purposes of this section in the same manner and to the same extent as such provision applies to the monitoring and data referred to in section 511 [probably means section 412 of the Clean Air Act, which is classified to section 7651k of this title]. Public Availability of Carbon Dioxide Information.—For each unit required to monitor and provide carbon dioxide data under subsection (a), the Administrator shall compute the unit’s aggregate annual total carbon dioxide emissions, incorporate such data into a computer data base, and make such aggregate annual data available to the public.”