---
kind: "section"
citation: "40 C.F.R. § 439.16"
title: "40"
number: "439.16"
heading: "Pretreatment standards for existing sources (PSES)."
url: "https://uscodex.org/cfr/40/439.16"
---

# §439.16. Pretreatment standards for existing sources (PSES).

- (a) Except as provided in 40 CFR [403.7](/cfr/40/403.7.md) and [403.13](/cfr/40/403.13.md), any existing source subject to this subpart must continue achieving the standards for cyanide specified in [paragraph (c)](#c) of this section and must achieve the following standards by September 21, 2001:
- (b) Sources that discharge to a POTW with nitrification capability (defined at [§ 439.1(i)](/cfr/40/439.1.md?p=i)) are not required to achieve the pretreatment standard for ammonia (as N).
- (c) The limitations for cyanide are the same as specified in § [439.12(e)](/cfr/40/439.12.md?p=e), [(f)](/cfr/40/439.12.md?p=f) and [(g)](/cfr/40/439.12.md?p=g).

## Notes

### Amendments

[68 FR 12272, Mar. 13, 2003]

### Authority

Authority: 33 U.S.C. 1311, 1314, 1316, 1317, 1318, 1342 and 1361.

### Source

Source: 48 FR 49821, Oct. 27, 1983, unless otherwise noted.

### Amendments

[68 FR 12272, Mar. 13, 2003]