StacksVerified U.S. regulatory reference

40 CFR §421.295

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
Except as provided in 40 CFR 403.7 and 403.13, any existing source subject to this subpart which introduces pollutants into a publicly owned treatment works must comply with 40 CFR part 403 and achieve the following pretreatment standards for existing sources. The mass of wastewater pollutants in secondary tin process wastewater introduced into a POTW must not exceed the following values:
  1. (a)Tin smelter SO2 scrubber.
  2. (b)Dealuminizing rinse.
  3. (c)Tin mud acid neutralization filtrate.
  4. (d)Tin hydroxide wash.
  5. (e)Spent electrowinning solution from new scrap.
  6. (f)Spent electrowinning solution from municipal solid waste.
  7. (g)Tin hydroxide supernatant from scrap.
  8. (h)Tin hydroxide supernatant from plating solutions and sludges.
  9. (i)Tin hydroxide filtrate.