Unwanted: 25 million tyres

People like John Green have had it up to here with illegal dumpers

Tyres are stacked high in front of John Green's warehouse in Rainham, Essex. That much you can see from the road, 200 yards away. Inside, you see the scale of the problem: tyres piled to the rafters, covering most of an area the size of two tennis courts.

The tyres are a big headache for Mr Green. All of them are useless, most with worn-out treads - and, more to the point, he didn't put them there. "People come in vans at night," he says. "Recently it's been truck tyres. Every time I come back here, there are more of them."

Mr Green is one of many victims of a waste-disposal scam that is thriving because old tyres, 25 million of which are scrapped in the UK every year, are extremely difficult to dispose of. They cannot be put in landfills because they are a fire risk. Nor can they be dumped in the sea, because they tend to leach heavy metals. And, although there is an incinerator in Wolverhampton, which burns them under controlled conditions, burning in the open air is not possible because they emit dangerous fumes.

Legal disposal companies tend to charge high prices for their services: as much as 40p for a car tyre and £5 for a truck tyre. At these prices, it is hardly surprising that when garage owners and tyre fitters are approached by less scrupulous operators with offers to dispose of them for as little as 20p for a car tyre and £3 for a truck, they often jump at the chance.

Illegal operators employ a variety of means to get rid of the tyres. Old airfields are a favourite - there is one near Grimsby that has more than a million stacked on it - but any unused space is viewed as an opportunity: empty office buildings, the land behind advertising hoardings, building sites, even rivers. "Recently, a bunch of tyres were spotted in the Thames," says a spokesman for the London Waste Regulation Authority (LWRA). "The woman who reported it said that at first she thought it was a monster."

The LWRA has a special squad, the Carriers Regulations Enforcement Team, that keeps tabs on all types of fly-tipping. Four undercover inspectors drive around the city day and night following suspicious vehicles and watching known dumping grounds. Tyres are an especially big problem because of the money that can be made from them. "There are some people out there who are earning as much as they would from running drugs," says one LWRA inspector. "It's not just fly-tipping, it's organised crime."

The number of prosecutions brought by the LWRA since January 1994 gives some idea of the scale of the problem. In total it has prosecuted 155 people for fly-tipping. Of those, 25 had committed tyre offences - involving 37 different incidents - and the LWRA says it knows of five tyre gangs operating in east London alone.

The squad says its limited powers are responsible for a failure to bring more people to book. It has to call the police to carry out arrests, and frequently people give them false addresses. "Even if we catch them at it, we can't do anything," says the LWRA inspector. "I've been in several situations where I've just had to stand by and watch while people continue tipping right in front of me."

Many of those convicted re-offend, because the fines imposed by the courts are minimal. One dealer, prosecuted last year for dumping tyres on four sites in east London, was fined £l,500 with £415 costs, and it is thought that he has now set up a similar business elsewhere. Another told the LWRA that he would be continuing to dump illegally, and said he regarded the inspectors as "an occupational hazard".

Meanwhile, the victims have to dispose of the tyres. The owner of the four sites in east London that were the subject of last year's court case says that clearing up costs currently stand at more than £7,000 - and the job isn't finished yet.

John Green, however, has given up thoughts of clearance at his Rainham warehouse. "What am I supposed to do?" he says. "I empty the site, and it fills up again. The only way to keep them out would be to build a large fence around the property - and I would have to foot the bill."

Mr Green believes the only way to stop the dumpers is for a levy to be charged on every tyre manufactured to pay for its ultimate disposal. (The Tyre Industry Council rejects this as too bureaucratic.) The LWRA inspector, on the other hand, argues that he should be given similar powers to those of his colleagues in other European Union countries, where environmental crime is taken very seriously. "In this country we hear that someone's been fly-tipping and we think it's a bit of a joke," he says. "If we were allowed to confiscate the vehicles of the people we catch, I guarantee that we would cut the problem by 60 per cent."

The situation, it seems, can only get worse. While tyre regulations throughout the EU permit 1.6mm of tread, people in other European countries generally renew their tyres when they get to about 2mm. As a result, more than 2 million part-worn tyres are imported into Britain every year. Owners of empty warehouses and offices had better beware.