This project is designed to show that it is possible to
implement safeguards around a program like North Korea's. The size
of the program is small compared to other safeguarded programs, and
showing that it is possible to safeguard a program of this size and
scope would give diplomatic discussions another route to deal with
nations who pursue these programs. This project follows the fuel
cycle of the North Korean program from the time Uranium (in the
form of yellow cake U3O8) enters the fuel fabrication facility all
the way through the reconversion of PuO2 at the Radiochemical
We start by analyzing how much raw material they need to make
enough fuel for their lone production reactor, the 5 MWe reactor.
The fuel fabrication facility is actually large enough to provide
enough fuel for both the 5 MWe reactor and a larger version, the 50
MWe reactor which was partially constructed but never finished.
However, because both use natural Uranium as the fuel, the total
amount of U-235 will be fairly small compared to domestic fuel
fabrication facilities. The 5 MWe reactor requires 50 metric tons
of natural Uranium fuel to be run, so that is the amount that we
will analyze. We will be looking to see if we can detect a
significant quantity of U-235, which is 75 kg according to the IAEA
in this form, being diverted for other purposes. To do this, we
will calculate the amount that comes in and the amount the goes out
and hopefully prove that any material unaccounted for is less that
the 75 kg significant quantity threshold.
After the fuel fabrication, the 5 MWe reactor must be analyzed.
Two things must be known about the reactor, how much Pu is produced
per core load at the stated power level of operation and what is
the maximum power they can run the reactor at. It is called the 5
MWe reactor due to its electrical output, but its thermal output is
rated at 20 MWth. Using a program called TransLAT, the reactor core
will be modeled in 2-d to determine total Plutonium production as a
function of burnup. After that, we will need to follow the known
power history of the reactor from open source materials to
calculate how much Plutonium has been made in that reactor. A
thermodynamics analysis will also ensure that the reactor cannot be
run at a much higher power than the North Korean's have claimed.
Higher power levels would allow them to make more Plutonium and
perhaps to hide some of that Plutonium production by switching out
fuel in between normal refueling operations.
The final step in the fuel cycle analysis comes from the
Radiochemical Laboratory. This is where they reprocess the spent
fuel from the 5 MWe and create either Plutonium metal or PuO2 for
use in the weapons program. It is known that they do not re-use the
Uranium also separated in this process. The Radiochemical
Laboratory uses a version of the PUREX process that is used in most
commercial and state-run reprocessing plants. The throughput of
fuel is low compared to other facilities, but that makes this job
actually a little easier. The total amount of Plutonium going
through the facility per core load is measured in kilograms, and
the detectors and sensors we would use to measure it would be able
to measure the amount to within a few grams, which should enable
the material unaccounted for in Plutonium to remain below the 8 kg
significant quantity threshold set by the IAEA. Proving this will
prove that this fuel cycle, and those with similar size and design,
are capable of having safeguards implemented.
Power profile of the core for Thermodynamic Analysis