Page 165 - Beyond Decommissioning

146 Beyond Decommissioning

number of high-tech companies and research organizations. Following the delicensing
of 7 ha in 2010 and 11 ha in 2011, 20% of the original Harwell site had been
decontaminated and delicensed by February 2012. Fig. 6.5 shows two remaining reac-
tors (Dido and Pluto), which have been kept under safe enclosure for many years.
It should be noted that, unlike land, the redevelopment (adaptive reuse) of individ-
ual buildings is often impractical. At Harwell 70% of prenuclear buildings could
be reused for nuclear activities, but only 5% are expected to be reusable through/after
the delicensing process. This typically happens because of deterioration or damage
incurred during decontamination, difficult-to-remove residual contamination or the
difficulty of proving the lack of contamination in drains or underlying soil. One rel-
evant example from Harwell is Building 146. The following quotation from Atyeo
(2010) lists various phases in the lifecycle of this building.
l “RAF Sergeants Mess 1930s.
l Modified 1946 to be radiochemical labs, vent system, glove boxes, early shielded facilities,
alpha handling
Refurbished in 1980s—equipment removed, vent system sealed in position, fixed contam-
l
ination sealed in position and placed under management control
Reused as offices occupied by a tenant on the licensed site until 2006. Also part used as a
l
nonnuclear laboratory
Final decommissioning in 2008 included removal of vent system and fixed contamination,
l
sealed contaminated drains, asbestos
l Removal of these systems rendered the building clean but unusable and it was demolished.”
The 60-year-old Capenhurst site in the UK consisted previously of two segments. One
part—a former diffusion uranium enrichment plant that shut down in 1982—was

Fig. 6.5 Dido and Pluto reactors at Harwell.
Photo by M. Laraia.