U.S. Code of Federal Regulations
Regulations most recently checked for updates: May 28, 2023
(a) Except as provided in 40 CFR 403.7 and 403.13, any existing source subject to this subpart must continue achieving the standards for cyanide specified in paragraph (c) of this section and must achieve the following standards by September 21, 2001:
Pretreatment Standards (PSES)
| Regulated
parameter | Maximum daily 1 | Maximum monthly average 1 |
|---|---|---|
| Ammonia (as N) 2 | 84.1 | 29.4 |
| Acetone | 20.7 | 8.2 |
| 4-methyl-2-pentanone | 20.7 | 8.2 |
| Isobutyraldehyde | 20.7 | 8.2 |
| n-Amyl acetate | 20.7 | 8.2 |
| n-Butyl acetate | 20.7 | 8.2 |
| Ethyl acetate | 20.7 | 8.2 |
| Isopropyl acetate | 20.7 | 8.2 |
| Methyl formate | 20.7 | 8.2 |
| Isopropyl ether | 20.7 | 8.2 |
| Tetrahydrofuran | 9.2 | 3.4 |
| Benzene | 3.0 | 0.7 |
| Toluene | 0.3 | 0.2 |
| Xylenes | 3.0 | 0.7 |
| n-Heptane | 3.0 | 0.7 |
| n-Hexane | 3.0 | 0.7 |
| Methylene chloride | 3.0 | 0.7 |
| Chloroform | 0.1 | 0.03 |
| 1,2-dichloroethane | 20.7 | 8.2 |
| Chlorobenzene | 3.0 | 0.7 |
| 20.7 | 8.2 | |
| Diethyl amine | 255.0 | 100.0 |
| Triethyl amine | 255.0 | 100.0 |
1 mg/L (ppm)
2 Not applicable to sources that discharge to a POTW with nitrification capability.
(b) Sources that discharge to a POTW with nitrification capability (defined at § 439.1(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), (f) and (g).
