Owners can claim special allowances for up to two flats in the event their premises must be torn down under the newly endorsed slum-clearance law. The new Urban Renewal Authority, empowered to acquire an area for demolition as it deems appropriate, will be set up next year to take over operations of the Land Development Corporation. Some 200 projects in Yau Ma Tei, Kwun Tong, Tsuen Wan and Wan Chai have been targeted, and it is hoped clearance can be completed in 20 years. Affected tenants who meet the conditions for public housing will be rehoused in Housing Authority or Housing Society rental flats. Landlords will be paid the market value of their flats plus an allowance to enable them to buy a comparable flat, up to 10 years old, nearby. Those with two or more flats will be paid - for the second unit - its market value and an allowance about half the value of a flat of similar size, up to 10 years old. Special payouts will not be considered for a third flat. Democrat Lee Wing-tat sought to amend the proposal to allow more lenient compensation, arguing buyers had paid full market value for their flats and should not receive less. But his amendment was voted down. With passage of the law yesterday, a provisional urban renewal authority is to be set up to supervise transfer of the corporation's assets. When the corporation was set up 12 years ago, many people believed it could rejuvenate some cramped older districts. It failed because of financial and legal constraints. Lengthy compensation negotiations had also delayed a number of projects. The Government then decided to create a new authority with more powers of acquisition and eviction. At present, about 8,500 urban blocks are more than 30 years old, of which 2,200 require urgent redevelopment.