[Code of Federal Regulations] [Title 40, Volume 27] [Revised as ofJuly 1, 2003] From the U.S. Government Printing Office via GPO Access [CITE: 40CFR436.20] [Page 350] TITLE 40--PROTECTION OF ENVIRONMENT CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PART 436--MINERAL MINING AND PROCESSING POINT SOURCE CATEGORY--Table of Contents Subpart B--Crushed Stone Subcategory Sec. 436.20 Applicability; description of the crushed stone subcategory. Source: 42 FR 35849, July 12, 1977, unless otherwise noted. The provisions of this subpart are applicable to the mining or quarrying and the processing of crushed and broken stone and riprap. This subpart includes all types of rock and stone. Rock and stone that is crushed or broken prior to the extraction of a mineral are elsewhere covered. The processing of calcite, however, in conjunction with the processing of crushed and broken limestone or dolomite is included in this subpart.