Two hundred workers at the ESB Moneypoint station in Co Clare have lost their jobs with immediate effect after the Polish sub-contractor they worked for was found not to be in compliance with employment law in Ireland.
The ESB said the decision to terminate the contract with ZRE Katowicz (Ireland) Construction was taken after monitoring of the company following a controversy over payments last year.
In May ZRE owned up to underpaying workers on the site.
The Technical, Engineering and Electrical Union (TEEU) claimed the company was paying workers €5.20 an hour, less than a third of the legally binding construction industry rate. The figures were disputed by the company but it admitted that an audit had uncovered "limited" underpayments.
A statement from ESB late last night said that Lentjes, the German-based main turnkey contractor on the upgrade of the coal-burning plant had taken the decision "in accordance with their contract with ZRE and the requirements of Irish labour and employment law".
The ESB said it was aware of a "number of outstanding issues" in relation to ZRE's compliance with labour and employment law in Ireland as a result of its monitoring service operated by Contractor Auditing Services (CAS).
CAS were brought in at the beginning of the €300 million project in 2005.
The decision was announced to workers at the plant yesterday evening.
An ESB spokesman said every attempt would now be made to repatriate the Polish workers with ZRE who are likely to have work in other agencies run by the company.
"We're dealing with Lentjes to ensure that everything is done properly and the workers are treated as fairly as possible.
Lentjes are endevouring to find an alternative contractor.
The spokesman added: "We have always striven to ensure that our contractors and sub-contracters are fully compliant, and this shows we take our responsibilities seriously in that regard.
"From the tendering process, we make sure that we pay our turnkey contractor sufficiently so that they can pay their sub-contractors properly".