[Code of Federal Regulations]
[Title 40, Volume 26]
[Revised as of July 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR422.51]

[Page 649]
 
                TITLE 40-PROTECTION OF ENVIRONMENT
 
      CHAPTER I-ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 422-PHOSPHATE MANUFACTURING POINT SOURCE CATEGORY--Table of Contents
 
       Subpart E-Defluorinated Phosphoric Acid Subcategory
 
Sec. 422.51  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) The term process waste water means any water which, during 
manufacturing or processing, comes into direct contact with or results 
from the production or use of any raw material, intermediate product, 
finished product, by-product, or waste product. The term 
``process waste water'' does not include 
contaminated non-process waste water, as defined below.
    (c) The term contaminated nonprocess waste water shall mean any 
water including precipitation runoff, which during manufacturing or 
processing, comes into incidental contact with any raw material, 
intermediate product, finished product, by-product or waste product by 
means of:
    (1) Precipitation runoff, (2) accidental spills, (3) accidental 
leaks caused by the failure of process equipment and which are repaired 
or the discharge of pollutants therefrom contained or terminated within 
the shortest reasonable time which shall not exceed 24 hours after 
discovery or when discovery should reasonably have been made, whichever 
is earliest, and (4) discharges from safety showers and related personal 
safety equipment, and from equipment washings for the purpose of safe 
entry, inspection and maintenance; provided that all reasonable measures 
have been taken to prevent, reduce, eliminate and control to the maximum 
extent feasible such contact and provided further that all reasonable 
measures have been taken that will mitigate the effects of such contact 
once it has occurred.
    (d) The term ten-year 24-hour rainfall event shall mean the maximum 
precipitation event with a probable recurrence interval of once in 10 
years as defined by the National Weather Service in technical paper no. 
40, ``Rainfall Frequency Atlas of the United 
States,'' May 1961, and subsequent amendments or 
equivalent regional or State rainfall probability information developed 
therefrom.
    (e) The term 25-year 24-hour rainfall event shall mean the maximum 
precipitation event with a probable recurrence interval of once in 25 
years as defined by the National Weather Service in technical paper no. 
40, ``Rainfall Frequency Atlas of the United 
States,'' May 1961, and subsequent amendments or 
equivalent regional or State rainfall probability information developed 
therefrom.

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