If there are practical difficulties or unnecessary hardships for an owner to comply with the rules under this act, the director may modify the application of those rules or if the spirit of the rules is observed and the public safety is secure. An owner may make a written request to the department stating its grounds and applying for a modification described in this section. Any authorization by the director under this section must be in writing and must describe the conditions under which the modification is permitted. The department shall keep a record of all modifications under this section that is open to the public.