(a) In any case in which the fund has paid benefits, including medical benefits, on behalf of an operator or other employer which is determined liable therefore, or liable for a part thereof, such operator or other employer shall simultaneously with the first payment of benefits made to the beneficiary, reimburse the fund (with interest) for the full amount of all benefit payments made by the fund with respect to the claim.

(b) In any case where benefit payments have been made by the fund, the fund shall be subrogated to the rights of the beneficiary. The Secretary of Labor may, as appropriate, exercise such subrogation rights.