[Code of Federal Regulations]
[Title 40, Volume 27]
[Revised as ofJuly 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR440.132]

[Page 433-434]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 440--ORE MINING AND DRESSING POINT SOURCE CATEGORY--Table of Contents
 
              Subpart L--General Provisions and Definitions
 
Sec. 440.132  General definitions.

    (a) ``Active mining area'' is a place where work or other activity 
related to the extraction, removal, or recovery of metal ore is being 
conducted, except, with respect to surface mines, any area of land on or 
in which grading has been completed to return the earth to desired 
contour and reclamation work has begun.
    (b) ``Annual precipitation'' and ``annual evaporation'' are the mean 
annual precipitation and mean annual lake evaporation, respectively, as 
established by the U.S. Department of Commerce, Environmental Science 
Services Administration, Environmental Data Services, or equivalent 
regional rainfall and evaporation data.
    (c) ``Appropriate treatment of the recycle water'' in subpart J, 
Sec. 440.104 includes, but is not limited to pH adjustment, settling and 
pH adjustment, settling, and mixed media filtration.
    (d) ``Groundwater infiltration'' in Sec. 440.131 means that water 
which enters the treatment facility as a result of the interception of 
natural springs, aquifers, or run-off which percolates

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into the ground and seeps into the treatment facility's tailings pond or 
wastewater holding facility and that cannot be diverted by ditching or 
grouting the tailings pond or wastewater holding facility.
    (e) ``In-situ leach methods'' means the processes involving the 
purposeful introduction of suitable leaching solutions into a uranium 
ore body to dissolve the valuable minerals in place and the purposeful 
leaching of uranium ore in a static or semistatic condition either by 
gravity through an open pile, or by flooding a confined ore pile. It 
does not include the natural dissolution of uranium by ground waters, 
the incidental leaching of uranium by mine drainage, nor the 
rehabilitation of aquifiers and the monitoring of these aquifiers.
    (f) ``Mill'' is a preparation facility within which the metal ore is 
cleaned, concentrated, or otherwise processed before it is shipped to 
the customer, refiner, smelter, or manufacturer. A mill includes all 
ancillary operations and structures necessary to clean, concentrate, or 
otherwise process metal ore, such as ore and gangue storage areas and 
loading facilities.
    (g) ``Mine'' is an active mining area, including all land and 
property placed under, or above the surface of such land, used in or 
resulting from the work of extracting metal ore or minerals from their 
natural deposits by any means or method, including secondary recovery of 
metal ore from refuse or other storage piles, wastes, or rock dumps and 
mill tailings derived from the mining, cleaning, or concentration of 
metal ores.
    (h) ``Mine drainage'' means any water drained, pumped, or siphoned 
from a mine.
    (i) ``Ten (10)-year, 24-hour precipitation event'' is the maximum 
24-hour precipitation event with a probable recurrence interval of once 
in 10 years as established by the U.S. Department of Commerce, National 
Oceanic and Atmospheric Administration, National Weather Service, or 
equivalent regional or rainfall probability information.
    (j) ``U'' (Uranium) is measured by the procedure discussed in 40 CFR 
141.25(b)(2), or an equivalent method.