4. The right of several fishery conferred by article 3 is subject to the following restrictions–
(a)the harvesting of scallops shall be carried out manually by divers; and
(b)the applicant shall not permanently moor within the limits of the area of the fishery any boat or other floating structure used by it in exercising its right of several fishery and any boat or other floating structure so used shall be moved from the area of the several fishery at the conclusion of each operation.