The Democrat Party claimed cronyism was behind a telecommunications company winning a lucrative deal to dispose of waste.

The party alleged the International Civil Aviation Organisation (ICAO) had opposed the building of a waste-disposal and treatment plant at the airport.

Democrat anti-corruption crusader Alongkorn Pollabutr said he planned to demand answers from Airports of Thailand Plc (AoT).

Alongkorn alleged there were irregularities behind a Samart Corp-led consortium winning a Bt566-million contract to dispose of waste from the new airport. Two other companies in the consortium are Professional Waste Technology Plc and Siam Waste Management Consultant Co Ltd.

Alongkorn questioned how Samart, with no experience in handling waste disposal and treatment, could secure the contract.

There were questions hanging over the plant, too. Alongkorn claimed the ICAO, which has been an adviser to the AoT, was against the plant's construction.

In addition, the terms of the contract were suspicious, the party asserted. It required AoT to pay compensation to the consortium if the airport failed to generate 40 metric tons of waste each day.

Alongkorn suggested the consortium had close ties to the Wongsawat family.

Somchai Wongsawat is a brother-in-law of caretaker Prime Minister Thaksin Shinawatra and chaired a committee that appointed AoT executives.

He noted the same consortium won several information-technology projects from the Justice Ministry and Survarnabhumi Airport between 2004 and 2006.

Some executives of the consortium were former board members of Shin Corp, he added.

Last year, the consortium helped to purchase 20 million shares from a Wongsawat family media company.

The Democrats asserted AoT and the government refused to co-operate with investigations of allegedly suspicious Suvarnabhumi airport deals.