Counties and towns whose equipment has been deployed by the commissioner for the cleanup and removal of petroleum discharges may apply to the commissioner for reimbursement of all costs incurred in such cleanup and removal, including the reasonable costs of equipment usage and the salaries and overhead of the operators. Reimbursement of such costs, where applicable, shall be based upon the equipment rates and such other approved rates which may have been or which may be established by the department. The commissioner shall examine such claims and certify such claims as are just to the administrator for payment.