The job of recovering the fissile material which accidentally spewed on to the floor of a shielded cell in September 2005 has been much tougher than initially envisaged. A failure of management systems led to intermediate-level active liquid waste spilling over a steel drum after an automatic mechanism to release its lid failed to activate.
Before the flow was stemmed, 58 gallons had poured out, much of it mixing with a separate feed of cement powder.
It has also halted operation at the plant where the highly-active liquor – viewed as the site's highest hazard – is cemented in drums before being put in long-term storage.
Those dealing with the clean-up initially envisaged having the plant back in action in the summer of last year at a cost of about £1 million. But it has proved much trickier than anticipated.
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