---
kind: "section"
citation: "40 C.F.R. § 124.20"
title: "40"
number: "124.20"
heading: "Computation of time."
url: "https://uscodex.org/cfr/40/124.20"
---

# §124.20. Computation of time.

- (a) Any time period scheduled to begin on the occurrence of an act or event shall begin on the day after the act or event.
- (b) Any time period scheduled to begin before the occurrence of an act or event shall be computed so that the period ends on the day before the act or event.
- (c) If the final day of any time period falls on a weekend or legal holiday, the time period shall be extended to the next working day.
- (d) When a party or interested person may or must act within a prescribed period after being served and service is made by U.S. mail, EPA's internal mail, or reliable commercial delivery service, 3 days shall be added to the prescribed time. The prescribed period for acting after being served is not expanded by 3 days when service is made by personal delivery, facsimile, or email.

## Notes

### Amendments

[48 FR 14264, Apr. 1, 1983, as amended at 82 FR 2237, Jan. 9, 2017]

### Authority

Authority: Resource Conservation and Recovery Act, 42 U.S.C. 6901 et seq.; Safe Drinking Water Act, 42 U.S.C. 300f et seq.; Clean Water Act, 33 U.S.C. 1251 et seq.; Clean Air Act, 42 U.S.C. 7401 et seq.

### Source

Source: 48 FR 14264, Apr. 1, 1983, unless otherwise noted.

### Amendments

[48 FR 14264, Apr. 1, 1983, as amended at 82 FR 2237, Jan. 9, 2017]