---
kind: "unit"
title: "40"
title_heading: "Protection of Environment"
key: "chI/subchD/part121"
level: "part"
label: "Part 121"
heading: "State Certification of Activities Requiring a Federal License or Permit"
release: "ecfr-current"
date: "2026-08-27"
url: "https://uscodex.org/cfr/40/chI-subchD-part121"
sections_count: 19
---

# Part 121 — State Certification of Activities Requiring a Federal License or Permit

Title 40 C.F.R. — Protection of Environment › Chapter I — Environmental Protection Agency › Subchapter D — Water Programs

## Contents

- [Subpart A — General](/cfr/40/chI-subchD-part121-subpartA.md)
- [Subpart B — Neighboring Jurisdictions](/cfr/40/chI-subchD-part121-subpartB.md)
- [Subpart C — Certification by the Administrator](/cfr/40/chI-subchD-part121-subpartC.md)
- [Subpart D — Review and Advice](/cfr/40/chI-subchD-part121-subpartD.md)
- [Subpart E — Severability](/cfr/40/chI-subchD-part121-subpartE.md)