[Code of Federal Regulations]

[Title 40, Volume 28]

[Revised as of July 1, 2006]

From the U.S. Government Printing Office via GPO Access

[CITE: 40CFR421.61]



[Page 479]

 

                   TITLE 40--PROTECTION OF ENVIRONMENT

 

         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)

 

PART 421_NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY--Table 

of Contents

 

                 Subpart F_Secondary Copper Subcategory

 

Sec.  421.61  Specialized definitions.



    For the purpose of this subpart:

    (a) Except as provided below, the general definitions, 

abbreviations, and methods of analysis set forth in 40 CFR part 401 

shall apply to this subpart.

    (b) For all impoundments constructed prior to the effective date of 

this regulation the term ``within the impoundment'' when used for 

purposes of calculating the volume of process wastewater which may be 

discharged shall mean the water surface area within the impoundment at 

maximum capacity plus the surface area of the inside and outside slopes 

of the impoundment dam as well as the surface area between the outside 

edge of the impoundment dam and any seepage ditch immediately adjacent 

to the dam upon which rain falls and is returned to the impoundment. For 

the purpose of such calculations, the surface area allowances set forth 

above shall not be more than 30 percent of the water surface area within 

the impoundment dam at maximum capacity.

    (c) For all impoundments constructed on or after the effective date 

of this regulation, the term ``within the impoundment'' for purposes of 

calculating the volume of process wastewater which may be discharged 

shall mean the water surface area within the impoundment at maximum 

capacity.

    (d) The term pond water surface area when used for the purpose of 

calculating the volume of wastewater which may be discharged shall mean 

the water surface area of the pond created by the impoundment for 

storage of process wastewater at normal operating level. This surface 

shall in no case be less than one-third of the surface area of the 

maximum amount of water which could be contained by the impoundment. The 

normal operating level shall be the average level of the pond during the 

preceding calendar month.