[Code of Federal Regulations] [Title 40, Volume 28] [Revised as of July 1, 2004] From the U.S. Government Printing Office via GPO Access [CITE: 40CFR439.4] [Page 401] TITLE 40--PROTECTION OF ENVIRONMENT CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PART 439_PHARMACEUTICAL MANUFACTURING POINT SOURCE CATEGORY --Table of Contents Sec. 439.4 General limitation or standard for pH. The pH must remain within the range 6.0 to 9.0 in any discharge subject to BPT, BCT or NSPS limitations or standards in this part. [68 FR 12271, Mar. 13, 2003]