[Code of Federal Regulations] [Title 40, Volume 20] [Revised as of July 1, 2003] From the U.S. Government Printing Office via GPO Access [CITE: 40CFR142.21] [Page 596] TITLE 40--PROTECTION OF ENVIRONMENT CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PART 142_NATIONAL PRIMARY DRINKING WATER REGULATIONS IMPLEMENTATION--Table of Contents Subpart C_Review of State-Issued Variances and Exemptions Sec. 142.21 State consideration of a variance or exemption request. A State with primary enforcement responsibility shall act on any variance or exemption request submitted to it, within 90 days of receipt of the request.