About 200 homes in County Antrim may have been built near contaminated land on the site of a former textiles factory.
Householders are being informed about the situation
Environment Minister Angela Smith says precautionary site investigations are to begin on the land at the old Courtaulds site in Carrickfergus.
She said Akzo Nobel, the company that acquired Courtaulds in 1998, told them of possible contamination in December.
Mr Smith said householders in the area are being informed of the situation.
The houses involved were built in the early 1990s after the factory closed. Before building took place, the land was checked for contamination but was found to be clear of any problems.
Six years ago, all of Courtaulds' operations in the UK were bought by the Dutch company Akzo Nobel.
They told the BBC that when they were going through some of Courtaulds' old documents, they discovered that there was a possibility that chemicals could have been dumped on one part of the land.
They stress that the houses involved are not built on the site where the material was dumped.
Although Akzo Nobel do not own the land nor have responsibility for it, they decided nevertheless to make the DOE aware of the situation and gave them the files.
As a result, the homes involved will be advised that chemical testing will take place in the area in due course.
The chemical thought to be involved, carbon disulphide, disperses in the open and its thought very unlikely that any traces of it would remain after all these years.
'Purely agricultural land'
The town's mayor, David Hilditch, said the council had written to residents in the Brackenridge and Ashbourne Manor areas and would keep them informed.
"It's only precautionary and hopefully within a few weeks things will pan out and any fear will be negated," he said.
"Everybody is going to work together - myself, my fellow councillors and the officials - for the well-being of the residents of Carrick."
Chemical testing will take place in the area in due course
Independent councillor Billy Hamilton, who used to work at Courtaulds, said many of the houses had been built on purely agricultural land.
Tom McDowell, who has lived in the Brackenridge estate for three years, said there had been no sign of a problem in the area.
"This is the first we have heard of this and as long as it is done correctly, and everything is above board, and the results come out okay, then I would be fine with that," he said.