The site of an aluminium factory in Enniscorthy, Co Wexford, which is due to close in July, is contaminated by a chemical solvent and will have to be monitored for up to 10 years, the Environmental Protection Agency has confirmed.
The ground around the Wexal factory, which manufactures radiators for the European motor industry, is contaminated by trichlorethylene which was used as a de-greasing agent during production in the 1970s and 1980s and now poses a threat to local water supplies.
Trichlorethylene or tricholor ethylene is a solvent used for degreasing metal parts and cleaning electrical and electronic equipment. Exposure to high concentrations can cause headaches, tremors, nausea and eventually unconsciousness and possibly death. It is also a strong irritant to eyes and skin.
The International Agency for Research on Cancer has concluded there is limited evidence for trichlorethylene being a cancer-causing agent, with liver and kidney tissues particularly susceptible. The US Environmental Protection Agency has yet to include it on its books as a cancer causing agent.
It regularly affects wells and nearby water supplies when allowed to drain into soils. There are hundreds of sites around the US where trichlor ethylene pollution has forced the closure of local wells.
It is a stable compound and so can remain in ground water and soils for some time, according to a chemist at University College Dublin. A US research study has shown, however, that bacterial action does break down the chemical over time.
Before Wexal leaves Enniscorthy it will be required to take out an insurance policy to cover the cost of providing alternative water supplies in the event of any of the existing supplies in the area becoming contaminated.
The problem, which came to light when the EPA assessed the plant for an Integrated Pollution Control licence in 1999, is expected to be a major stumbling block in efforts by the IDA to find a replacement industry for the site.
The EPA has carried out tests on farmland and properties near the factory, and no traces of the chemical have been found in groundwater.
An EPA spokesman said the company was asked as a condition of its licence to produce an investigation and remediation programme. It hired specialist environmental consultants, Dames and Morgan of Dublin and Cork, to compile reports and make recommendations.
Last week Wexal wrote to the EPA announcing the planned closure and undertaking to continue monitoring the contamination to ensure it did not cause groundwater pollution at any stage in the future.
"The company has undertaken to comply with the licence and to decommission the plant properly and safely," said the EPA spokesman, adding that the IPC licence in respect of Wexal would remain effective for some years.
In the event of the site being sold, the licence obligations would pass to the new owner. Depending on how the contaminant broke down or travelled in the soil, the site would have to be kept under scrutiny for as long as 10 years. "It needs to be managed. There is a sufficient amount of the material there that it could flow off," he said.
"However, I don't think it's a major scare," the EPA spokesman said. "The owners have been very responsible about it and are managing it with the support of the EPA, and all the reports are there for any potential buyer to see."
The managing director of Wexal, Mr Patrick d'Helft, said the rules governing the use of chemicals were not as strict 20 years ago. "It is not really very harmful but it is not going away," he commented.