The transport and storage of water, which led to the collapse of several mining pillars, was the "probable reason for the subsidence" that caused a sinkhole to open up near Carrickmacross, Co Monaghan.
A preliminary report into the event found the sinkhole was caused by “unique and complex” factors.
It said recent operations in an old part of a mine involving the transport and storage of water led to the collapse of the pillars, the report said. The section of the mine had not previously been used to store water.
Gyproc is an Irish plaster and plasterboard manufacturer that has mining operations in the area. The company met with officials from Monaghan County Council on Wednesday, to discuss the independent report into the sinkhole.
“The report indicates that these circumstances do not appear to be present elsewhere in the vicinity, though naturally the company is taking all precautions and conducting further investigations to ensure this is the case,” the firm said in a statement on Wednesday night.
Earthquake trench
The subsidence has a radius of 120 metres, with the appearance of an earthquake trench, and was discovered at Magheracloone Mitchell’s GAA club on Monday morning. It damaged two pitches, the GAA clubhouse and community centre building, and led to the indefinite closure of the building due to safety concerns.
We currently can't say when the families can move back or when we can give sufficient reassurances to allow them return to their homes.
“Outside of the actual disturbance zone, an area of investigation including five houses and two stretches of public road has been identified,” the company said.
“Gyproc has been in regular contact with the families in the affected houses to ensure they have appropriate support and have also appointed an experienced family liaison officer from the company to ensure the families have as much help from Gyproc as possible,” the statement said.
The company said it was also in contact with Magheracloone GAA Club and the Community Centre, and had offered financial support to replace the damaged clubhouse.
The company said it had a “long and respected mining history in the area for over 80 years” and operated to the highest professional standards.
Earlier on Wednesday, the chief executive of Monaghan County Council, Eamon O'Sullivan, said it was unclear when families could move back to their homes which were damaged by the sinkhole.
Monitoring
Monitoring and measurement of conditions will continue over the coming days, Mr O'Sullivan told RTÉ's News at One.
“We currently can’t say when the families can move back or when we can give sufficient reassurances to allow them return to their homes.”
Mr O’Sullivan said until the results of investigations are verified independently, the council “will have to maintain, in the interests of public safety and road safety, a precautionary approach.
“So the existing exclusion zone is currently in place and will remain. The R179, Carrickmacross to Kingscourt road, will continue to remain closed and local primary road 4900 to the school will also remain closed.”
Mr O’Sullivan said the families who had to leave their homes are being accommodated in local hotels by the mining company. That was obviously not satisfactory in the long term, he added, but said nothing could be done until the root cause of the problem was determined.
