[Code of Federal Regulations] [Title 40, Volume 27] [Revised as ofJuly 1, 2003] From the U.S. Government Printing Office via GPO Access [CITE: 40CFR436.140] [Page 357] TITLE 40--PROTECTION OF ENVIRONMENT CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PART 436--MINERAL MINING AND PROCESSING POINT SOURCE CATEGORY--Table of Contents Subpart N--Potash Subcategory Sec. 436.140 Applicability; description of the potash subcategory. Authority: Sec. 306, Federal Water Pollution Control Act, as amended. The provisions of this subpart are applicable to the processing of potash. Potash obtained from brine lakes is regulated in the saline from brine lakes subcategory (subpart L of this part).