More than half a million tonnes of material was buried without permission in and around a licensed recycling site at Campsie.Experts from the Northern Ireland Environment Agency (NIEA) disposed of high risk refuse and monitored water quality over the last seven months ahead of consideration of a longer term solution.SDLP Environment Minister Mark H Durkan said the scale of illegal dumping discovered was "like nothing we've ever seen before on this island or on these islands"."Therefore the cost of the clean-up, we can assume, is going to be colossal. It would be my ambition and my desire that we make the polluter pay for the clean-up of this site," he said.Most of the illegal landfill was buried in old sand and gravel excavation pits across a 1.4km site on Mobuoy Road near the River Faughan.Independent expert Chris Mills investigated and said clearance costs could ultimately be "tens of millions of pounds".Unfortunately, the penalties that currently are associated with waste crime are not a sufficient deterrent when compared with the vast and huge profits that can be gained from it.Environment Minister Mark H DurkanThe licence for the owner and operator of the recycling site was revoked and a criminal investigation launched, with two arrests made.Mr Mills was commissioned by former Environment Minister Alex Attwood to examine the case.He noted a history of non-compliance with regulations at the licensed site, but said it was still not known who deposited the illegal waste."However, this was a sophisticated operation which had been carried out over a number of years," he added.Mr Durkan told DUP MLA Gregory Campbell costs incurred to date by the Department of the Environment were around £800k."NIEA is engaging top-class experts to advise on longer term clean-up options at the Campsie site, including cost estimates," he added."Clean-up decisions will be based on this expert advice which will include detailed estimates of the likely costs and timescale."