A specialist team has been brought in to clear up asbestos lagging which fell off a heat exchanger at the Chapelcross nuclear plant in Dumfriesshire.
A specialist team has been called in to the Annan plant
About 20kg of the material crashed onto a staircase after becoming waterlogged during the weekend storms.
Air samples showed levels of asbestos remained within safe limits but the area was sealed off as a precaution.
The plant stopped producing electricity in 2004 and is currently going through the decommissioning process.
All decommissioning work in the vicinity of the incident has been suspended.
Specialist contractors have been drafted into the Chapelcross site to clear up the affected area.
The work is expected to be complete within the next few weeks.
The remaining asbestos lagging on the plant's heat exchangers is scheduled to be removed next year as part of the site clean-up programme.
Asbestos fibres - if inhaled - can have very serious effects on health.