Campaigners have welcomed a stiff penalty handed out to a fly-tipper who desecrated a Somerset woodland.

Andrew Austwick, aged 41, of Taunton, was ordered to complete 70 hours of unpaid community work and pay £500 in clean-up and legal costs. He had admitted dumping the contents of a closed post office on land at 20 Acre Plantation, near Cothelstone, on the Quantock Hills, in August last year.

Last night the Country Land and Business Association, the CLA, said the penalty should sound a very loud warning to other would-be fly-tippers.

But, it said, it still believed not enough was being done to stamp out a problem which government figures suggest is costing farmers and landowners about £50 million a year.

Mr Austwick was prosecuted by Taunton Deane Borough Council after leaving the rubbish lying on part of an Area of Outstanding Natural Beauty.

Council prosecutor Maria Casey told the court a Quantock Hills warden had found items including a glass-fronted display fridge and a cash register.

She said the waste had been cleared away by council staff at a cost of £280. The authority's environmental protection team started inquiries which eventually led to Austwick's home and the prosecution was launched after he failed to respond to requests to meet the officers.

Austwick told the magistrates: "It was my own fault. I should have gone by the rules and I did not. I'm sorry."

After the case Cllr Mel Mullins, executive member for environmental services, said he was pleased the court had recognised the seriousness of the offence and awarded a substantial penalty.

"We live in a beautiful part of the country and we want to keep it that way," he said.

"Let anyone who may be thinking of fly-tipping be in no doubt of the council's determination to gather evidence and prosecute cases of this environmental crime".

Fly-tipping has become one of the greatest problems facing farmers and landowners, particularly those on the urban fringes, in recent years. Farmers say the introduction of the landfill tax has only exacerbated the problem, and many are now regularly left to deal with abandoned fridges and furniture dumped in gateways or in ditches. In October, Defra published figures suggesting incidents of illegal waste dumping were declining. But the CLA says the figures are misleading because they exclude private land. It says reports from its members suggest there is little sign of any such decline happening.

Spokesman Paul Millard said even the official estimate of £50 million that fly-tippers are said to cost landowners was probably on the low side.

But, he said, the penalty handed out by Taunton magistrates was exactly the kind of approach that was needed.

"We have been campaigning for many years to persuade the authorities, particularly the police and Environment Agency, to take stronger action against these criminals – because criminals is what they are," he said. "However, all too often fly-tipping is a criminal offence which no-one really wants to take ownership of, while for years landowners have been left with both the costs and the job of clearing up.

"Our argument has always been that we should adopt the principle of 'the polluter pays' and that these people should be pursued as vigorously as possible.

"Ideally, we would like to see a change in the law which would make it easier to pursue offenders and bring them to court, and which allows courts to impose penalties which really reflect the scale of desecration that offences like this all too often involve."

Penalties for fly-tipping are fines of up to £20,000 and six months' imprisonment. Fines are unlimited if the case goes to the Crown Court, where jail terms can be increased to two years – five if hazardous waste is dumped.

Where fly-tipping involves the use of a vehicle, the driver can be prosecuted, as well the owner, and police have powers to seize vehicles used for fly-tipping.

Official Home Office advice to farmers and others is never to approach anyone they see fly-tipping as they may become violent. The waste should be left untouched and containers unopened in case they contain hazardous material.

But the date, time and place of the occurrence, what the waste looks like and how much of it there is, and a description of any vehicle involved along with the registration number should be reported to the local authority or to the Environment Agency.