22 Dec Activity, Progress, and Creativity Characterized 2011
DD has had a demanding year, encompassing three major projects and numerous smaller assignments. Progress on the projects has been notable, despite occasional procurement challenges that necessitated innovative problem-solving.
22011 has been both a busy and exciting year for DD, with primary focus on three major projects: the Hot Cell facility, the DR 3 research reactor, and preliminary studies for a final repository for radioactive waste. The year presented both progress and challenges, requiring flexibility and creative solutions.
One of the major milestones for 2011 was the dismantling of the peripheral systems of the DR 3 research reactor. This milestone was achieved when the last facility, BOE (which purified helium cover gas for the reactor), was removed on December 13, 2011. The reactor now stands 'bare' and ready for the second phase, which involves the removal of the reactor's internal components (reactor tank, top shield, etc.) and the demolition of the heavy water room and the reactor block itself.
Throughout the year, the DR 3 group concurrently prepared the comprehensive project description for phase two. The project description was approved by the nuclear regulatory authorities in December 2011, thereby giving the green light for the continued decommissioning of Denmark's last research reactor.
The second major project, the decommissioning of the Hot Cell facility, proved more challenging than anticipated, and furthermore necessitated the use of unconventional tools.
A Tank in the Hot Cells
According to the plan, the cleaning of the six highly radioactively contaminated concrete cells should have commenced in 2011. However, acquiring the appropriate customized and remote-controlled equipment proved more difficult than initially assumed. Consequently, the project team had to re-prioritize, focusing instead on tasks that were originally scheduled for a later stage, rather than cleaning the cells.
One of these tasks, the removal of the conveyor channel, required an alternative solution and assistance from the toy industry. In the Hot Cell facility, the approximately 30-meter-long channel runs beneath the tables, traversing the cells. The channel served for transporting smaller items between the six cells. Transport was carried out by a conveyor trolley, which could be moved back and forth within the conveyor channel using a chain drive.
In preparation for the removal, characterization studies were conducted to determine the extent of radioactive contamination in the channel, including the presence of any 'hot spots' (very small particles with high radioactivity content). As the channel is difficult to access due to both its size and its location within the contaminated cells, the project had to resort to unconventional methods to assess the degree of contamination. For this purpose, DD's workshop purchased a remote-controlled toy tank, which was small enough to navigate through the channel.
The tank was equipped with an extra-long cable, camera, light, and radiation detector, and sent through the channel. The tank's reconnaissance revealed several 'hot spots' in addition to the one indicated in the old documentation. This information will be used to determine the necessary safety measures when the channel is subsequently removed from the facility.
Preliminary Studies for Final Repository Published
Another milestone achieved by DD in 2011 was the publication of preliminary studies for a final repository for radioactive waste. On Wednesday, May 4, 2011, the sub-reports were presented to political parties and subsequently published on the Ministry of Health's website. The identification of 22 suitable and six recommended areas for the location of the final repository garnered considerable attention from both the media and the affected municipalities. Subsequently, DD was busy inviting the media to showcase the radioactive waste and explain the background of the preliminary studies.
All indications suggest that 2012 will be equally busy for the company. The DR 3 project's first task will be the demolition of the heavy water room beneath the reactor block. For the Hot Cell project, the focus will be on preparing and executing the remote-controlled sandblasting of paint from the cells' internal surfaces, as well as procuring equipment to extract the used abrasive and paint and transfer it to DD's waste drums.