NRL responds to
the Boston Globe
Below is the NRL response to
the 29 December 2009 Boston Globe article entitled "Potent
Fuel at MIT Reactor Makes Uneasy Politics" by Bryan Bender of the
Globe Washington DC office.
Certain basic facts were available to the Globe prior to publication
of the article, but did not appear clearly in the article.
One premise of the article was that the MIT Reactor (MITR)
could be converted immediately to low-enriched uranium (LEU) fuel if
only MIT were willing to accept a small (~10%) decrease in the reactor's
performance. While this statement is true for many low-power university
reactors, it is not true for the MITR. Also comments in the article on
the security of our fuel inventory are highly misleading. In particular,
the following should be noted:
1. The MITR has a very compact core, as do several
of the other high performance research reactors including the ones at
Missouri-Columbia, NIST, and at Oak Ridge National Laboratory. These
reactors can NOT attain criticality using the LEU fuel that has been
developed by the Department of Energy (DOE). It is not a question of
accepting a small decrement in performance. Conversion with the existing
LEU would mean that the MITR could no longer operate. The existing LEU
has a density of 4.8 grams/cc. For the MITR to maintain criticality and
a reasonable fuel cycle, a density of about 14 grams/cc is required.
DOE has candidate fuels that will achieve this density under development.
However, efficacy has yet to be shown -- tests of the material's properties
are still underway at the Advanced Test Reactor in Idaho.
2. MIT is committed to convert to LEU and has been
so committed in writing with the Nuclear Regulatory Commission since
the mid 1980s when the LEU conversion effort was initiated in the U.S.
We have not, as the article stated, blocked or delayed the program.
We have pointed out the need for a high-density LEU fuel that would enable
all the high performance reactors to maintain criticality. Conversion
planning is currently a major activity at the MIT Nuclear Reactor
Laboratory, but again it hinges on the DOE development of a suitable fuel,
followed by NRC certification. We strongly concur with current plans
to implement the new fuel in 2014.
3. Our existing highly-enriched
uranium (HEU) fuel is safe from diversion. The MITR has always had excellent
security and is constantly evaluating and upgrading security. Fresh
fuel is brought in the day of a planned refueling under enhanced security,
and immediately placed in the reactor core for irradiation. Thus, there
is almost never any fresh fuel on site, and it is limited to much less
than the amount needed to make a weapon. As regards irradiated fuel,
it is highly radioactive. NRC defines fuel to be "self-protecting" in
the sense that it is sufficiently radioactive so that anyone stealing
it would suffer serious health consequences if it exceeds 100 rads per
hour at one meter. One can debate the adequacy of this level. For someone
who does not value their life, it is not a deterrent. However, MITR
fuel greatly exceeds this level and would cause serious, often debilitating,
illness and/or death if anyone were to remove it without massive shields
that could not be concealed.