The decommissioning of old mortars took place in 1999. The mortars, 200 in all, were purchased from Brandt, a French company, in the period 1936 to 1955.
On the recommendation of a military board of survey, the mortars were converted to scrap in Clancy Barracks in Dublin. The scrapped mortars were removed to the Irish Steel plant, ISPAT, in Haulbowline, County Cork in October 1999 for reprocessing.
When the scrapped mortars arrived in the Irish Steel plant, the radiation detection alarm on the premises was activated. Irish Steel, as required by law, alerted the Radiological Protection Institute of Ireland and the scrap was not accepted.
A technical expert from the RPII was requested to investigate the source and extent of the radiation and to advise on procedures. He identified the source of the radiation as the radionuclides, radium 226 and radium 228. The radium is found in the luminous strip on the cross levelling bubble located on the bipod of the mortar. It is understood that wrist watches which were manufactured around the same period were luminised with similar radioactive material.
The RPII has stated that a person would have to be in very close proximity to the illuminating bubble of a mortar stand for a minimum of 4,000 hours to be subjected to the safe allowable annual amount of radiation. Taking into account the level of usage of this type of equipment in the Defence Forces, it is impossible for members of the Defence Forces to be subjected to anything near to the safe allowable annual amount of radiation.
The task of isolating those cut mortar bipod sections which were radioactive was undertaken by ordnance personnel on 19 October 1999. All personnel involved were adequately protected using disposable overalls, face masks, gloves and personal dosimeters. The non-radioactive scrap was handed over to Irish Steel for reprocessing. The isolated segments were returned to Clancy Barracks in Dublin.
The isolated radioactive segments are stored in steel bins in Clancy Barracks in a special radioac tive materials storage facility. This facility is constructed in accordance with international requirements for the storage of such items and comes under the RPII for audit and inspections. The material will remain in this facility until a new one is built in the new Defence Forces logistics base in the Curragh. The facility is operated in accordance with RPII guidelines. Should the RPII guidelines change, the military authorities will update their instructions as required.
It is mandatory for the Department of Defence and the Defence Forces to maintain a register and inventory of all radioactive substances and to be licensed by the RPII in that regard. The Department and the Defence Forces meet all the requirements of the RPII in that regard. The Defence Forces has carried out a full audit of the ordnance materials and systems under its control and none presents any hazard from radiation.
