40 C.F.R. § 425.60
Applicability; description of the through-the-blue subcategory.
Cite as 40 C.F.R. § 425.60 (2026)
The provisions of this subpart are applicable to process wastewater discharges resulting from any tannery which processes raw or cured cattle or cattle-like hides through the blue tanned state by hair pulp unhairing and chrome tanning; no retan-wet finishing is performed.