SURAT THANI: The mountain of garbage, 45,000 tonnes of it, that is polluting Koh Tao island is to finally be removed with the signing of a contract with a new firm that has promised to properly dispose of it all.

"We'll certainly clear it up and make Koh Tao a perfect, pollution-free tourist attraction," Surat Thani governor Witchawut Chinto said on Wednesday during a visit to inspect the mess on the island.

The spreading eyesore of foul-smelling garbage has authorities worried it could seriously damage the island's reputation as a divers' paradise.

The 21-square-kilometre island in the Gulf of Thailand is not far from Koh Phangan, an island which has earned notoriety for its Full Moon parties.

The garbage piled up after the company previously hired to dispose of it was fired, its contract not renewed due to its failure to fulfil the terms, Mr Witchawut said.

This left the only garbage incinerator on the island idle, with nobody to operate it.

A new company has now been hired to remove the rubbish, the governor said.

They will also introduce better waste management over the long term, including recycling. 

Koh Tao is one of the tourist magnets of southern Thailand, drawing about 3 million visitors a year and revenue around 10 billion baht annually. Its reputation has been damaged following a number of deaths of tourists on the island, in particular the brutal murder of two British tourists in 2014 and the subsequent charging of two Myanmar nationals, who many believe to be scapegoats.