An official investigation is to take place into claims that Polish workers employed by a contractor at the ESB power station in Moneypoint are being paid less than a third of the legal minimum rate.
The Technical, Engineering and Electrical Union (TEEU) said the 66 workers, employed on a €350 million refurbishment of the power plant, were being paid just €5.20 an hour.
However, both the ESB and the main contractor involved, German company Lentjes, said yesterday they had already uncovered the problem and steps had been taken to rectify it.
Officials from the TEEU are to meet the workers' Polish-owned employer, ZRE Katowice (Ireland) Construction, tomorrow.
The company could not be contacted yesterday but its industrial relations consultant, John Kennedy, said he had not been notified of any problems regarding its pay rates.
In a statement, however, the ESB confirmed that a breach of agreed pay rates had been identified at the site.
It said "possible irregularities" involving a sub-contractor, understood to be ZRE Katowice, had been highlighted following an independent audit, commissioned by the ESB, in early February.
It said the sub-contractor had agreed to rectify the situation, and a further audit would be carried out this month to ensure it had done so. It is understood the Polish company's contract could be cancelled if it is found not to be in compliance with labour laws when the next audit takes place.
A separate investigation, meanwhile, is to be undertaken by the labour inspectorate of the Department of Enterprise, Trade and Employment. A spokeswoman said last night the inspectorate had been in contact with both the ESB and the TEEU and would be pursuing the matter immediately.
The matter came to light yesterday at a press conference called by the union, which said it was concerned that a "Gama-type scenario" could exist at the Co Clare power station.
Gama Construction was accused last year of grossly underpaying its migrant workers.
As fitters/welders, the Polish workers are entitled to a minimum wage of €18.97 an hour under the construction industry's registered employment agreement (REA).
They are also entitled to a subsistence allowance of €157.09 per week, the TEEU said.
In this case, however, the workers were being paid just over €1,000 a month for a 52-hour week, with no overtime premiums. This amounted to €5.20 an hour. It said the company had claimed there were additional benefits such as accommodation, which is provided, and travel costs, but these were not itemised on pay slips.
TEEU general secretary Owen Wills claimed the fact that the ESB was the client, showed that "even in the public sector" assurances that labour laws were being complied with "are not worth the paper they are written on".
Mr Wills rejected any suggestion that the TEEU had timed its press conference to put maximum pressure on employers in the current talks on a national partnership agreement, at which unions are seeking a tightening of labour laws.
ZRE Katowice has been operating in Ireland since 2003. It reports to Lentjes, the main contractor involved in the Moneypoint Environmental Retrofit Project.
In a statement last night, Lentjes said the anomalies had been identified in the wages paid to employees of the Polish firm, but these had been "addressed fully" in the past two weeks.