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Title 40

Displaying title 40, up to date as of 6/11/2026. Title 40 was last amended 6/11/2026.
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§ 439.16 Pretreatment standards for existing sources (PSES).

(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
o-Dichlorobenzene 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).

[68 FR 12272, Mar. 13, 2003]