THE controversial mid-stream container project in Tuen Mun will be put out for tender next month after the Government managed to win support from the District Board. The site will accommodate boats which unload cargo from large ocean-going vessels - now based in Tsing Yi, where the land is to be cleared for Container Terminal 9. District Board members walked out in protest over the plan in February, saying container trucks entering and leaving the site would worsen the traffic on the Tuen Mun Highway. The Environmental Protection Department also warned of possible noise disturbance to nearby residential estates. The proposal eventually won a one-vote majority last month when it was tabled for the second time with a government promise that container trucks would not be allowed to enter the site and only sea traffic would be allowed. Strict noise mitigation measures have also been imposed. The United Democrats remain sceptical that the requirements will be observed and will set up a special group to monitor the situation. ''We don't believe the operator can work without using container trucks,'' Willy Ng Wai-cho said. The Principal Marine Officer of the Port Development Board, Tsang Man-ching, pledged to closely monitor the operators. He said the operators might risk having their tenancy terminated if they did not observe the requirements. Mr Tsang said the site could be in operation by late next month, adding it would be able to handle about 400 containers a day.