40 C.F.R. § 429.90
Applicability; description of the wood preserving—Boulton subcategory.
Cite as 40 C.F.R. § 429.90 (2026)
This subpart applies to discharges to waters of the United States and to the introduction of process wastewater pollutants into a publicly owned treatment works from wood preserving operations which use the Boulton process as the predominant method of conditioning stock.