A PLAN to destroy 15kg of a lethal chemical in the Wicklow Mountains has sparked public safety fears.

South Dublin County Council has confirmed the waste hydrogen cyanide will be destroyed by explosion later this month.

The operation is being overseen by the Army, Department of Defence, Garda, the Health and Safety Authority, the HSE, and the council's health and safety team, the council said.

The chemical is a once commonly-used agricultural poison and a concentration of 300mg per cubed metre of air is lethal to humans within minutes.

It is listed in Schedule 3 of the UN Chemical Weapons Convention as a potential weapon of mass destruction.

The material is no longer used as a fumigant in countries which are signatories to the convention.

The council said it was approached by pest-control company Rentokil about the safe destruction of its stock of hydrogen cyanide which has been on site for decades.

Advice

Advice from the council's own health and safety team, chemical experts and the chemical manufacturer was that cylinders containing the material -- including seals and valves -- were intact and safe.

The plan is being risk-assessed by international contractors who are experts in chemical destruction.

The Environmental Protection Agency said it accepted assurance from experts that the explosion and burning methods involved are acceptable.

The destruction will involve the material being taken by road to Kilbride military camp, near Brittas in west Co Wicklow by June 23.

Seven canisters will be involved in the operation, five of which are empty and two of which are partially empty.

The canisters will be placed in a larger container of diesel. An explosive charge will be used to blow open the canisters while the burning diesel will then burn off the hydrogen cyanide.

A council spokesman admitted there is no doubt the material is dangerous. "It can kill, it is dangerous, but the destruction is as safe as we can make it," he said.

Councillor John Brady said he is unhappy with the process and the site. He said locals had not been told of the plans.

Mr Brady (SF) added that there is a risk to hill walkers, livestock and the local river, which, he said, drains into the Blessington reservoir.

- Cormac Murphy