Solid Radioactive Waste Strategy Report.pdf - UK EPR

EPR UK
N° NESH-G/2008/en/0123
REV. A PAGE 98 / 257
8.1.2.3 Other Equipment (Nuclear Steam Supply System (Except Primary Circuit),
Nuclear Island, Maintenance)
Classifications of waste of the Nuclear Steam Supply System and Balance of Nuclear Island
inventories are indicated respectively in Table 18 and Table 19. Contaminated concrete
(excluding the activated concrete of the reactor pit) is classified LLW for 75t and VLLW for
455t.
8.1.3 Dismantling and waste management options
Techniques for safely decommissioning and dismantling an EPR already exist and have
been demonstrated on previous decommissioning projects.
Four main factors will have influence on the decommissioning strategy adopted by a utility:
· Acceptance for disposal of ILW to the proposed UK deep geological disposal facility;
· Acceptance for disposal of LLW to a Low Level Waste Repository;
· Legal and regulatory framework at the time of decommissioning;
· Radiological status of the plant after 60 years of operation.
Strategic options will be refined during the operational phase of the EPR through dialogue
with relevant regulators. Experience gained from other decommissioning and dismantling
projects will be considered.
At the present time, the baseline scenario for decommissioning and dismantling is:
Dismantling methodologies considered for the EPR is as follows:
· Dismantling of strongly and moderately activated components remotely under water.
These components are located in the reactor pit which is designed to be flooded to
enable work to be carried out on reactor core components. The reactor core
components, especially the neutron shield, have been designed for ease of
dismantling and removal;
· Dismantling of contaminated components and slightly activated components in
contact with air;
· Dismantling will make maximum use of the EPRs static and dynamic containment.
The access routes to the reactor containment building have been designed to allow
import of dismantling equipment and export of large components;
· Use of auxiliary buildings erected for the dismantling. Once the reactor has been shut
down and fuel removed from the nuclear island, redundant auxiliary buildings can be
refurbished to support decommissioning and waste management;
· Cutting of components will be completed to separate and categorise waste with
respect to radiological classification and to provide size-reduced pieces which are
compatible with the designated packaging;
· Main Coolant Pipes and Reactor Coolant Pumps are removed from their location
inside the Reactor Building to a workshop at the building floor service in order to be
size reduced for packaging;
· Removal of Steam Generators as complete units from their respective shielded
enclosures (“pillboxes”) to a treatment building outside of the reactor building;
· The polar crane within the reactor building has been designed for the handling of
heavy equipment and reactor components during decommissioning. Lighter
components can be handled by other means specific to the task.