Regulations last checked for updates: Oct 02, 2026

Title 40 - Protection of Environment last revised: Sep 29, 2026
§ 439.4 - General limitation or standard for pH.

The pH must remain within the range 6.0 to 9.0 in any discharge subject to BPT, BCT or NSPS limitations or standards in this part.

[68 FR 12271, Mar. 13, 2003]
source: 48 FR 49821, Oct. 27, 1983, unless otherwise noted.
cite as: 40 CFR 439.4