The figures emerge as the Department of Education starts handing back the first €10m of unspent funds previously made available to retrain former Waterford Crystal, SR Technics, and Dell staff.
The 377 ex-construction workers who availed of grants up to the end of April are among just 808 who made inquiries to the department about accessing the European Globalisation Adjustment Fund (EGF).
The department applied two years ago for funding on behalf of 9,089 workers made redundant between Jul 2009 and Mar 2010.
Following approval for EGF support last October, it wrote to 8,779 with Irish addresses before Christmas, and the scheme closed three weeks ago. The Government is set to provide 35% of the cost of the scheme.
Last October, Education Minister Ruairi Quinn said he had concerns about the maladministration of the scheme under the previous government.
In the Dáil last week, Sinn Féin finance spokesperson Pearse Doherty asked Ciarán Cannon, minister of State, what has been done since then to avoid similar failures, with at least €10m going back to Europe.
Mr Doherty called for an independent probe into the operation of the funds “to establish where administrative and political responsibility lies”.
He said the €55m scheme for ex-construction workers, with €35m coming from the EU, is probably the worst organised as eligible workers were not contacted until 10 months after the Government took office.
Mr Cannon said he started a review of the application process immediately after taking office, but that it was never the intention of the process that all the approved money would be spent.
“EU statistics indicate that the average reimbursement is of the order of 46%. We are currently under that figure, at 44.5%,” he said.
He said the full spend and amount to be reimbursed will not be known until after final reports are due back to the European Commission in early December.