(1) No later than 60 working days after a land use plan has been submitted to it, the commission shall, after public hearing and by majority vote of those members present, determine whether the land use plan, or a portion thereof applicable to an identifiable geographic area, raises no substantial issue as to conformity with the policies of Chapter 3 (commencing with Section 30200). If the commission determines that no substantial issue is raised, the land use plan, or portion thereof applicable to an identifiable area, which raises no substantial issue, shall be deemed certified as submitted. The commission shall adopt findings to support its action.