RADIATION LEVELS AT CARRYING OUT THE REFURBISHMENT
OF THE BULGARIAN RESEARCH REACTOR IRT 2000
I. S. Dimitrov, Tz. Nonova, Al. Mladenov, K. Krezhov
Received: 01 APR 2015, Received revised: 07 MAY 2015, Accepted: 08 MAY 2015, Published Online: 28 APR 2016
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The paper presents a summary of the main steps in carrying out the refurbishment of the research reactor IRT in Sofia. It was a 2 MW pool type light water cooled and moderated reactor which after the final shutdown was defueled and brought to a state of safe enclosure. According to a decision of the Bulgarian Government it undergoes a reconstruction into a low-power reactor. In this regard during the period 2008 - 2014 within the IRT-Sofia took place a number of activities with potential for radiation hazard such as shipping of the spent nuclear fuel, dismantling of the reactor internals and replacement of aged reactor equipment, categorization, sorting and packaging for temporary storage of dismantled equipment and the radioactive waste generated during the dismantling activities.
The report gives information on the organization and management of the activities and outlines some key technical aspects of the dismantling and removal of the contaminated/activated components. Also, the experience gained during this project is highlighted, particularly with a view to methods for the separation of radioactive waste from material to be cleared. The radiation measurements and site monitoring prior, for the period of all the activities and at present supplied comprehensive evidence that the work has been accomplished safely for the personnel and without radiation consequences for environment.
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