The Office of Environmental Enforcement and Meath County Council are to examine the contents of two illegal dumps near Duleek and Drumconrath in a bid to identify the waste collector involved.
The two dumps at Drumconrath near Ardee, and Tymoole near Duleek, each contain an estimated 10,000 tonnes of mixed household and construction waste.
The office said the focus of the initial investigations would be to gather sufficient evidence to establish who was responsible and to prosecute those involved for what the agency described as an "environmental crime".
Test drilling at both sites has already begun to determine the quantity and type of the waste, but also to ascertain drainage conditions and soil types which will influence the remedial measures required.
Meath County Council would not confirm the ownership of either site yesterday, but it has emerged that the illegal landfill near Duleek is owned by the Fingal Harriers Hunt which bought the land about four months ago.
Fingal Harriers has told investigators that it first became aware something was amiss when methane gas started to emanate from the ground.
The hunt immediately called in Meath County Council which identified an illegal dump which, it estimated, contained about 10,000 tonnes of household and construction waste.
The Drumconrath dump also contained a similar amount of household and construction waste.
The director of environmental services for Meath County Council, Mr Joe Fahy, said yesterday that Section 55 notices had been served on both landowners notifying them of the find and of the subsequent investigation.
Tests will also be carried out to determine if there is any risk to human health involved, he said.
In Mr Fahy's opinion, the amount of waste uncovered would suggest that the dumps had been in operation for less than a year.
But he could not say if their discovery had interrupted an ongoing business. "These things may be stop-start operations" he commented.
A spokesman for the Department of Environment said that under the Waste Management Act, landowners were responsible for unauthorised dumps on their land.
Where a landowner was not aware of the presence of the dump, the Protection of the Environment Act placed the burden of proof of that lack of knowledge on the landowner, the spokesman said.
Most residents around the Duleek site were unwilling to comment publicly yesterday, but some said they had been aware of the dumping and had even complained to the council about the number of lorries in the area.
Outside the Fingal Harriers Hunt premises at Tymoole, a sign gave both mobile and landline telephone numbers for the club, but nobody was available at either number.
In nearby Duleek, the Labour party candidate in the Meath by-election, Mr Dominic Hannigan, said the latest discoveries represented only a fraction of the amount of holes in the ground and fly-tipping in the county.
