[Code of Federal Regulations] [Title 40, Volume 28] [Revised as of July 1, 2006] From the U.S. Government Printing Office via GPO Access [CITE: 40CFR421.80] [Page 489] TITLE 40--PROTECTION OF ENVIRONMENT CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PART 421_NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY--Table of Contents Subpart H_Primary Zinc Subcategory Sec. 421.80 Applicability: Description of the primary zinc subcategory. Source: 49 FR 8808, Mar. 8, 1984, unless otherwise noted. The provisions of this subpart are applicable to discharges resulting from the production of primary zinc by either electrolytic or pyrolytic means.