More than 780,000 applications have been awarded compensation under the plans.
The schemes have now closed to new claimants but the level of compensation paid is expected to keep rising - possibly to more than £7bn once all claims have been settled, Newsquest Newspapers reported.
Court judgements in the late 1990s found British Coal was negligent in failing to take appropriate measures to preserve the health of former pitmen. The Government then agreed to take on the subsequent liabilities, setting up the two compensation schemes.
