Technologies developed by the US military, such as satellite imagery and overflights by light aircraft using infra-red photography, are being used by Wicklow County Council to establish the extent of illegal dumps near Blessington.
The technologies are being deployed by environmental consultants investigating suspected dump sites on land owned by Roadstone and others in the area, according to Mr Michael Nicholson, the council's director of environmental services.
"The purpose is to pinpoint suspicious-looking areas, so that we're not floundering around in the dark," he told The Irish Times. "What the imagery does is to show up abnormalities in ground conditions where waste might be dumped."
Temperature differentials in the land are registered by the overflight infra-red photography and satellite imagery, which Mr Nicolson likened to the techniques used by water diviners. Sites containing decomposing material register a higher temperature.
Without such sophisticated technology, he said, trying to establish the location and extent of illegal dumps would be "a needle-in-a-haystack job".
But with work resuming yesterday on trial boreholes, "we should know a lot more by the end of this week". The work is being supervised by specialist environmental consultants engaged by the county council in October 2001, after the first of a spate of illegal dumps in Co Wicklow was discovered in a mainly disused quarry at Coolnamadra, south of Baltinglass.
Last July the council won a significant High Court action which resulted in the owner of the site and the directors of the company, Dublin Waste Ltd, being made personally liable for creating a pollution risk and for the costs of remediating the dump.
The site being investigated near Blessington extends to more than 500 acres in three separate ownerships, Roadstone, the Carnegie brothers and the Hudson brothers. All three have been engaged in quarrying there for many years.
Mr Nicholson said Roadstone had been co-operating fully in the investigation and had even supplied machinery to assist the council. The company, a subsidiary of CRH plc, has denied that it had any knowledge of illegal dumping on its lands. Boreholes are being dug to a depth of 15 metres, with monitors to detect the presence of methane gas. Where the gas reaches levels high enough to trigger an alarm, the site is vacated until it is ventilated, in accordance with normal practice.
Claims made by Mr Frank Corcoran, president of An Taisce and a resident of Blessington, that work had to be suspended before Christmas after dangerously high levels of methane were recorded have been denied by Mr Nicholson.
It is expected that the consultants will make an interim report on their findings at the end of this week, including the results of their environmental forensic examinations.