Regions of Highest Radiological Hazard

1 As with the AGR, when considering FWR decommissioning, there are three major sources of radiological hazard, namely, radioactive source materials, activated materials and contaminated materials. In the FWR these hazards can be Identified as follows  

These consist of the fuel assanblles dilch must be removed from the reactor via the existing fuel handling route before any decommissioning work can begin, after the reactor has been brought to a normal cold shutdown condition. 

These consist of materials which have been In the path of the neutron stream emanating from the reactor core during the normal operational life of the reactor. These materials absorb the 

2) The RPV Internal structures which support the core material and control rod mechanisms. 

3) The region of the primary shield wall adjacent to the active core. Ihe activated zone would extend approximately 1.0m to 1.5m radially into the wall from the reactor cavity face and similar dimensions above and below the active core region. See figures 48 to 52. 

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