5. Any claim by any injured person in for the costs of cleanup and removal and direct and indirect damages based on the strict liability imposed by this section may be brought directly against the person who has discharged the petroleum, provided, however, that damages recoverable by any injured person in such a direct claim based on the strict liability imposed by this section shall be limited to the damages authorized by this section.
6. Notwithstanding any other provision of this section, a volunteer firefighter, volunteer fire company, volunteer fire district, volunteer fire protection district, or volunteer fire department shall not be strictly liable for discharged petroleum when such discharge results from such volunteer firefighter, volunteer fire company, volunteer fire district, volunteer fire protection district, or volunteer fire department performing his, her, or their firefighting duties and there is not a showing of willful or gross negligence. This subdivision shall not be construed to provide an exemption from liability for a discharge of petroleum on or from real or personal property owned, leased, or operated by any such volunteer fire company, volunteer fire district, volunteer fire protection district, or volunteer fire department.