# 18 CFR § 1318.103: Supplements

> Federal · Regulations · In force

URL: https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.103

## Section

- **Citation:** 18 CFR § 1318.103
- **Heading:** Supplements
- **Jurisdiction:** Federal
- **Kind:** Regulations
- **Status:** In force
- **Text as of:** September 22, 2026
- **Source:** Publisher's official text
- **Location:** Title 18—Conservation of Power and Water Resources > CHAPTER XIII—TENNESSEE VALLEY AUTHORITY > PART 1318—IMPLEMENTATION OF THE NATIONAL ENVIRONMENTAL POLICY ACT OF 1969 > Subpart B—Initiating the NEPA Process

## Text

(a) After completion of an environmental document, if TVA makes substantial changes in the proposed action that are relevant to environmental concerns or there is substantial new circumstances or information about the significance of the adverse effects that bear on the proposed action or its impact, and important components of the proposed action remain to be implemented, TVA will determine how the environmental document should be supplemented or modified. TVA may supplement an environmental document by issuing a new document that addresses changes in the proposed action or new circumstances or information or may modify the existing document so that revisions and edits to the original document are apparent. A supplemented or modified environmental document will be published.
(b) After completion of an environmental document, if TVA determines that changes to the proposed action that are relevant to environmental concerns are not substantial or new circumstances or information are not significant or relevant to environmental concerns, and therefore supplemental analysis is not warranted, TVA will document this determination consistent with § 1318.102.

## Nearby sections

- [18 CFR § 1318.10 § 1318.10 Purpose and policy.](https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.10.md)
- [18 CFR § 1318.20 § 1318.20 Abbreviations.](https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.20.md)
- [18 CFR § 1318.30 § 1318.30 Definitions.](https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.30.md)
- [18 CFR § 1318.100 § 1318.100 Determining when NEPA applies.](https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.100.md)
- [18 CFR § 1318.101 § 1318.101 Determining the appropriate level of NEPA review.](https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.101.md)
- [18 CFR § 1318.102 § 1318.102 Determination of NEPA Adequacy.](https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.102.md)
- [18 CFR § 1318.103 § 1318.103 Supplements.](https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.103.md)
- [18 CFR § 1318.104 § 1318.104 Reliance on existing environmental documents.](https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.104.md)
- [18 CFR § 1318.105 § 1318.105 Lead and cooperating agency determinations.](https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.105.md)
- [18 CFR § 1318.106 § 1318.106 Schedule for the NEPA process.](https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.106.md)
- [18 CFR § 1318.107 § 1318.107 Scoping process.](https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.107.md)
- [18 CFR § 1318.200 § 1318.200 Purpose and scope.](https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.200.md)
- [18 CFR § 1318.201 § 1318.201 Extraordinary circumstances.](https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.201.md)
- [18 CFR § 1318.202 § 1318.202 Public notification.](https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.202.md)

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Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/ecfr-18-1318.103. Check the current official text before relying on it. Not legal advice.