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Title 40

Displaying title 40, up to date as of 6/09/2026. Title 40 was last amended 6/08/2026.
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§ 421.94 Standards of performance for new sources.

Any new source subject to this subpart shall achieve the following new source performance standards:

Subpart I—Metallurgical Acid Plant—NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per/million pounds) of 100 pct sulfuric acid capacity
Arsenic 3.550 1.584
Cadmium 0.511 0.204
Copper 3.269 1.558
Lead 0.715 0.332
Zinc 2.605 1.073
Fluoride 1 89.390 50.820
Molybdenum 1 [Reserved] [Reserved].
Total suspended solids 38.310 30.650
pH (2) (2)
1 For Molybdenum acid plants only.
2 Within the range of 7.5 to 10.0 at all times.

[50 FR 38343, Sept. 20, 1985, as amended at 55 FR 31697, Aug. 3, 1990]