[Code of Federal Regulations]
[Title 40, Volume 29]
[Revised as of July 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR436.52]

[Page 350-351]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 436_MINERAL MINING AND PROCESSING POINT SOURCE CATEGORY
--Table of Contents
 
                      Subpart E_Gypsum Subcategory
 
Sec. 436.52  Effluent limitations guidelines representing the degree of effluent
reduction attainable by the application of the best practicable control 
          technology currently available.

    Except as provided in Sec. Sec. 125.30 through 125.32, any existing 
point source subject to this subpart shall

[[Page 351]]

achieve the following effluent limitations representing the degree of 
effluent reduction attainable by the application of the best practicable 
control technology currently available (BPT):
    (a) For operations not employing wet air emissions control scrubbers 
there shall be no discharge of process generated waste water pollutants 
into navigable waters.
    (b) Only that volume of water resulting from precipitation that 
exceeds the maximum safe surge capacity of a process waste water 
impoundment may be discharged from that impoundment. The height 
difference between the maximum safe surge capacity level and the normal 
operating level must be greater than the inches of rain representing the 
10-year, 24-hour rainfall event as established by the National Climatic 
Center, National Oceanic and Atmospheric Administration for the locality 
in which such impoundment is located.

[40 FR 48657, Oct. 16, 1975, as amended at 60 FR 33967, June 29, 1995]