Tender documents stipulate a buffer area to which access can be restricted The government wants to build a moat or other kind of buffer zone around its new headquarters at Tamar to help keep out the public when it deems necessary. Tender documents issued yesterday call on the contractors to provide a strip of 'amenity' space between the public area and the buildings, to which access 'may be restricted from time to time'. The strip should be 'water surface (preferably), and/or grassland, and/or fountain features etc'. It should be less than 10 metres wide and designed to 'promote visual enjoyment and to discourage unscrupulous intrusion'. The rest of the open space, including a 500-square-metre piazza and waterfront promenade, will be designated for public use. The documents also call on the contractors to carry out a site investigation to ascertain the nature of its soil and marine sediment, including the level and extent of contaminants. Opponents of the project have claimed the soil and seabed are heavily polluted after decades of use as a naval base by the British. The buildings should not encroach on marine sediment and should not require the disposal of a large quantity of contaminants, the documents say. A government spokeswoman said: 'The assessment report is to ensure the buildings will not encroach on the seabed.' In June, the government won a battle over funding for the new headquarters, with legislators voting 40-10 in favour of a HK$5.16 billion funding request for the project. The funding was approved despite suggestions that dioxin had been found at the Tamar site. The government denied this, saying only that there were heavy metals and organic chemicals in the soil. Four contractors were selected in May to bid for the project. They are a joint venture between China State, Leighton and Yau Lee; the DHK-CRCC Tamar Joint Venture; a Gammon and Hip Hing joint venture; and another between Paul Y and Shui On. The tender deadline is January 26 and the government expects construction will be completed by the end of next year. The public will be allowed to see the proposed designs after the tender closes. Their views will be presented to the Special Selection Board headed by Chief Secretary Rafael Hui Si-yan, which will consider the project consultant's analysis in assessing the submissions. The documents say 60 per cent of the scores that will be awarded to bidders will be based on design and aesthetics; planning, sustainability and environmental aspects; function and technical factors. Price accounts for the other 40 per cent. Paul Zimmerman, convenor of the group Designing Hong Kong Harbour District, said public opinion should have a role in the scoring system. 'The government missed an opportunity to showcase it by genuinely listening to the public's views,' he said.