Notwithstanding any other provision of the Rhode Island general laws to the contrary, whenever the council and the director have approved the beneficial use, dewatering or disposal of dredged material, the applicant, the site owner and/or the site operator, and any successors or assigns, shall not be responsible for any current and future liability that arises out of the approved beneficial use, dewatering or disposal and that is associated with the release or threatened release from the dredged material, provided there is compliance with the conditions imposed by the approval, and further provided that with regard to the beneficial use, dewatering or disposal, the site owner and/or the site operator, and any successors or assigns have acted in a responsible and prudent manner.