15 Dec Watch video: Rough cleaning of Hot Cells underway

Following several years of planning and preparatory work, the highly radioactively contaminated Hot Cells are now undergoing decontamination.

TThe Hot Cell facility comprises six interconnected concrete cells, which were utilized from 1964 to 1989 for processing radioactive materials. Given the elevated radiation levels, prolonged access to these cells is currently unfeasible; consequently, the initial radioactive decontamination is carried out using remote-controlled sandblasting.

Work inside the cells is performed through a series of openings in the 1.7-meter-thick concrete walls. As these openings progressively narrow closer to the cell's interior, it has not been feasible to utilize existing robotic arms available on the market. Instead, DD's employees have independently developed the primary components of the rough decontamination equipment.

One mechanical arm handles sandblasting with steel particles, guided by a pair of laser beams for aiming. Another arm carries the camera, which personnel outside the cell use for orientation. From the ceiling, a so-called light lance provides both illumination and an additional perspective on the work. A third arm is used for the subsequent vacuuming of spent steel particles and flakes of contaminated paint from the cell's walls and floor. A custom-built ventilation system ensures a constant negative pressure within the cells, while a separate system of pipes, hoses, and a large cyclone funnel directs the vacuum cleaner's stream of steel particles and paint into drums.

All equipment and work processes were thoroughly tested in a so-called mock-up cell, a 1:1 replica of the actual cells, before full-scale implementation.

Note: The video has no sound.