What is "Low-Level Radioactive Waste"
Over the years we have heard the phrase "low-level radioactive waste"
(LLRW) used in connection with the idea of establishing a "disposal site"
(i.e. dump) somewhere in West Texas take the wastes. Although originally the
idea was to have a state agency operate such a facility, the Legislature last
year made it possible instead for a private company to license a LLRW dump.
And, this dump will be allowed to accept waste from nuclear weapons facilities
all over the country. In other words, bringing radioactive waste into Texas
can now be a profit-making (and potentially very lucrative) business; the
more waste, the more money to be made.
Q: Low-level radioactive waste means stuff used in medical facilities, right?
A: Radioactive medical waste is indeed classified as LLRW, but so is, for example, cesium-137, a material which, under the regulations written for the Texas dump, could give a lethal dose of radiation to an unprotected person three feet away in eighteen minutes.
Q: So what is the definition of low-level radioactive waste?
A: The simple definition, in the United States, is: All nuclear waste that
is not legally high-level waste, some transuranics waste, or uranium mill
tailings. Not terribly useful, is it? A little simpler (though somewhat less
complete) would be to say that LLRW is everything radioactive in a nuclear
power plant, except the reactor fuel core. This includes pipes in contact
with highly radioactive water for decades, control rods from the core, filters
and sludge from cleaning the water in the reactor and fuel pool, and, finally,
the entire power plant if and when it is dismantled - thousands of tons of
contaminated concrete and reinforcing steel. None of the radioactive elements
(radionuclides) in high-level waste is prohibited from inclusion in low-level
waste. In fact, not a single radionuclide is barred from being dumped at the
proposed site in West Texas.
Q: What do you mean when you say LLRW is "highly radioactive?"
A: Radioactivity is measured in CURIES, which indicates how much radioactive
energy is being emitted. One curie is a lot - 37 billion emissions a second,
and any of those hitting your body can harm a cell and turn it cancerous.
Typically, all of the medical waste generated in a year in all of Texas would
give off a fraction of one curie. In contrast, a nuclear reactor generates
concentrated wastes that emit thousands of curies every year.
Q: Doesn't radioactive material become less dangerous over time as the radioactive elements decay?
A: Yes, this is true, but the real question is, how much time? For radionuclides, time is measured in "half-lives," which is the amount of time it takes for the element to give off half of its radioactivity. One reason that medical radioactive waste is not considered to be as much of a problem (besides its small amount) is that the half-lives of the vast majority of the elements used are counted in hours and days. The half-life of most elements found in nuclear reactor waste is measured in years, from dozens to thousands of years. Even worse, some of the waste expected to go to commercial LLRW sites from federal weapons facilities has half-lives of hundreds of thousands to millions of years.
Another time measurement for radioactive material is its hazardous life, the amount of time it should be monitored and controlled. The hazardous life is considered to be 10 - 20 half-lives. So, the cesium-137 mentioned at the beginning of these questions as being so deadly, has a half-life of only 30 years (though that is twice as long as the license for the dump), but is dangerous for 300 - 600 years. That's a pretty long lifespan for a business!
Q: So what happens to the radioactive waste at a commercial dump in Texas? And what happens if the company operating it goes bankrupt or disappears?
A: Here is how the new law answers these questions: