Solid Radioactive Waste Strategy Report.pdf - UK EPR

EPR UK
N° NESH-G/2008/en/0123
REV. A PAGE 124 / 257
9.1.2 Thermal Characteristics
The EPR reactor is designed to use both MOX and uranium oxide fuels. For the purposes of this
report it is assumed that the reactor uses uranium oxide fuel only. The uranium oxide fuel is
designed with a variety of enrichments, the maximum being 5%. The isotopic composition of the
spent fuel depend upon the initial enrichment, whether the fuel has been produced from natural
uranium only or whether reprocessed uranium has been used and the fuel management regime
conditions to which it is subject in the reactor. The average core region fuel burnup is less than
65,000 MWd/tU.
Spent fuel assemblies are discharged from the reactor and placed into the spent fuel pool to
cool and decay for a period of about 10 years before being moved to an interim storage facility.
The decay heat generated by an EPR spent fuel assembly (fuel manufactured with natural
uranium) which has undergone four 13 month reactor cycles and 10 years of cooling in the
Spent Fuel Pool is approximately 1,400 Watts at the time of interim storage. A spent fuel
assembly manufactured from reprocessed uranium, under the same conditions, would have a
heat output of 2000 Watts.
9.1.3 Spent Fuel Quantities
The UK EPR is designed for an operational life of 60 years. At any given time the operational
reactor will contain around 127 tonnes of enriched uranium fuel. Reactor refuelling will take
place at the end of reactor cycles which can range between 12 and 22 months depending on
the fuel management regime adopted. The quantities of spent fuel discharged from the reactor
during refuelling can be up to 80 assemblies. The EPR produces between 40 and 60 spent fuel
assemblies per year of operation. The number of fuel assemblies produced over the operation
of the EPR is 3400 (this equates to 1794 te of uranium).
9.2 Summary of Core Activated Components
During the operation of the UK EPR, a number of core components used to control or measure
neutron activity will need to be replaced during outages. These components when removed
from the reactor are highly activated and transferred to the Spent Fuel Pool where they are left
to radiologically decay.