Environmental Engineering Reference
In-Depth Information
tive materials will remain at reactor sites nationwide. As of January 2008, hundreds of tons of
spent fuel and other high-level radioactive wastes were stored in this manner at twenty-four
decommissioned nuclear reactors and 104 operating power plants throughout the United States
(USEIA 2011a).
Radioactive wastes are the leftovers from the use of nuclear materials for the production of
electricity, diagnosis and treatment of disease, and other purposes (USNRC 2002). The United
States in April 2008 had about 56,000 metric tons of spent fuel and 20,000 canisters of solid
defense-related waste; these amounts are expected to increase to 119,000 metric tons by 2035
(Physicians for Social Responsibility 2009, 1; Olesky 2008). Lacking a central repository, spent
fuel continues to accumulate in temporary storage at each of the 104 operating reactor sites. In
the United States, radioactive materials and the wastes produced from using them are subject
to regulatory control by the federal government or federally approved programs in thirty-two
states (USNRC 2002).
The U.S. Department of Energy (DOE) is responsible for radioactive waste related to
national defense, including nuclear weapons production and certain research activities. The
NRC and some states regulate commercial radioactive waste produced by electricity genera-
tion and other nonmilitary uses of nuclear material. The Environmental Protection Agency,
the Department of Transportation, and the Department of Health and Human Services also
have smaller roles in regulation of radioactive material (Fentiman and Saling 2002). Com-
mercial radioactive waste is of three basic types: mill tailings (discussed above), low-level
waste, and high-level waste.
Low-Level Radioactive Waste
Commercial radioactive wastes that are not high-level wastes or uranium and thorium milling
wastes are classified as low-level radioactive waste. Low-level waste includes items that have
become contaminated with radioactive material or have become radioactive through exposure
to neutron radiation. This waste typically consists of contaminated protective shoe covers and
clothing, wiping rags, mops, filters, reactor water-treatment residues, equipment and tools, lu-
minous dials, medical tubes, swabs, injection needles, syringes, and laboratory animal carcasses
and tissues. Low-level waste is typically stored on-site by licensees, either until it has decayed
away and can be disposed of as ordinary trash or until amounts are large enough for shipment to
a low-level waste disposal site in containers approved by the U.S. Department of Transportation
(USNRC 2011d). Three low-level waste facilities located in the United States are in Barnwell,
South Carolina, Richland, Washington, and Clive, Utah. They accept waste only from certain
states or only limited types of low-level wastes (USNRC 2002). Facilities licensed by NRC take
steps to reduce the volume of radioactive waste after it has been produced. Common means are
compaction and incineration. Approximately fifty-nine NRC licensees are authorized to incinerate
certain low-level wastes, although most incineration is performed by a small number of commercial
incinerators (USNRC 2002).
Radioactive waste with a short half-life is often stored temporarily before disposal in order to
reduce potential radiation doses to workers who handle and transport the waste, as well as to reduce
radiation levels at disposal sites. NRC authorizes some licensees to store short-half-lived material until
the radioactivity is indistinguishable from ambient radiation levels and then dispose of the material
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