UNIONS have reacted with anger after construction firms announced details of a compensation scheme for workers whose names were on a blacklist, saying the amount being offered was "grossly inadequate".

Eight companies said that following months of talks, the scheme had been finalised and was now open to applications.

Compensation will range from £4,000 where "minimal information" was held, to £20,000 for those whose entries included more details. The companies involved are Balfour Beatty, Carillion, Costain, Kier, Laing O'Rourke, Sir Robert McAlpine, Skanska UK and Vinci PLC. The blacklist, containing more than 3,200 names of mainly building workers, was discovered five years ago when offices of the Consulting Association were raided by the Information Commissioner.

The two sides are due in court next week, while unions maintain talks had broken down because of the "inadequate" amount of compensation being offered.

Steve Murphy, general secretary of UCATT, said: "This is a deeply cynical attempt by the blacklisting companies to try to prevent workers, who have had their lives ruined, getting justice."

Justin Bowden, GMB national officer, said: "To try and present such a grossly inadequate sum of money as meaningful compensation suggests they are sorry only they got caught."

A spokeswoman for the construction companies said: "The eight companies that have created The Construction Workers Compensation Scheme (TWCS) are disappointed the unions have chosen to take a negative stance on the development of the scheme which now reflects many of the changes they had called for."