It ranges from R100,000 to R500,000.
The accused include government officials and business owners as well as the director of Blackhead.
The company was paid R255-million for work that was never done.
It made R200-million to manage the project which was subcontracted.
Edwin Sodi, the director of Blackhead, was granted R500,000 bail.
All seven have had to surrender their passports.
They face charges of corruption, money laundering and theft.
Investigations are continuing and more arrests are expected.