The rural committee that ordered the illegal excavation of hundreds of tonnes of boulders from the Tung Chung river on Lantau will next week be consulted by the government on how to repair what green groups have labelled an environmental disaster. Island district lands officer Lau Chi-ming said yesterday that as the damage was done by the Tung Chung Rural Committee, it was its responsibility to restore the river. He said authorities would meet the committee and wait for its report before deciding how the river should be restored. 'The way they do it must meet our standard, that is the reason why they have to prepare a report for us,' Mr Lau told Commercial Radio's Teacup in a Storm. But Green Power, the environmental group that exposed the scandal, said restoration should begin immediately. Its chief executive, Man Chi-sum, said: 'This is a very unusual case and a terrible environmental disaster. The government has to act immediately.' Some 400 tonnes of boulders were excavated illegally from the Tung Chung river between Shek Mun Kap and Shek Lau Po by Tung Chung villager and contractor Wong Yat-wah, who claimed the works were for flood prevention. Rural committee head Law Kam-fai hired Mr Wong for the job. Dr Man warned that the river had been badly damaged and said a thunderstorm would result in the banks' total collapse and cause flooding. He also questioned whether the rural committee had the expertise to restore the river. 'The Agricultural, Fisheries and Conservation Department should assemble all the relevant experts to study how the river could be restored,' he said. In addition to the removal of 400 tonnes of boulders, thousands of tonnes of soil were excavated from the river bed and piled up to create an illegal access road next to the river, reduced to a trickle as a result. The boulders were sold to a subcontractor involved in the creation of a lake near the Penny's Bay Disney site, but the rocks were rejected because of their suspicious origin.