Re: How much nuclear waste is in the U.S.?

Hi Corey, 
This is one of my favorite questions.  First off, in a broad sense, there
are two classifications for radioactive waste: low level and high level.  

First, we’ll cover low-level waste.  Low-level radioactive waste (LLRW)
accounts for ~90% of all radioactive waste in terms of total quantity. 
Typically, about 135,000 cubic feet of LLRW is generated in the US each
year.  Actually, the number has been going down at a steady rate since
about 1980 when the laws governing LLRW changed.  Essentially, it became
VERY expensive to dispose of it and space began to run out at the 3
facilities able to accept this type of waste for disposal.  Since then, the
nuclear industry has done everything it can to limit the amount of waste
produced through best engineering practices.  (That is a good thing.)  The
actual things that make up LLRW are widely varied.  They include,
contaminated clothing, gloves, tools, boxes, containers, certain types of
radiopharmaceuticals, rocks, even dirt (rarely).  The list goes on and on,
actually.   

Now we’ll cover high-level radioactive waste (HLRW).  HLRW is almost
entirely composed of spent nuclear fuel from nuclear power plants.  A
modest amount is from medical use and other commercial radiation devices. 
Since the first nuclear reactor (The Chicago Pile reactor, December 2,
1942) to present, the total mass of HLRW from power plants is about 40,000
tons.  (Currently, the rate of generation is about 2,000 tons per year.) 
If all of the fuel assemblies were stacked side-by-side and end-to-end on a
football field, the stack would be about 16 feet tall.  (Thanks to the
Nuclear Energy Institute for the volume comparison.)  While this seems like
an enormous amount, I would point out that amount of ash produced by all of
the coal fired power plants in the US happens at a rate of ~30 tons per
second.  That means that in about 23 minutes, coal plants create as much
waste as all of nuclear energy combined in the more than 40 years of large
scale commercial nuclear power plant operations.  Not only that, but the
ash from coal is radioactive and a hazardous solid chemical waste.  The
overwhelming majority of the ash goes to landfills.  What I find most
amusing is that they line the dump pits with plastic or clay to keep the
"harmful" things from seeping into the water we drink.  This does not work,
in case you were wondering.  

I hope this adequately answers your question!

Scott Kniffin
Radiation Effects and Analysis Group
Flight Electronics Branch
NASA Goddard Space Flight Center