The applicant, any affected state, any affected interstate agency, any affected country, the regional administrator, or any interested agency or person may request a public hearing with respect to a draft permit determination. Any such request for a public hearing shall be filed within the thirty-day period prescribed in WAC 173-220-050(2) and shall indicate the interest of the party filing such request and the reasons why a hearing is warranted. The department shall hold a hearing if it determines there is a significant public interest. Instances of doubt will be resolved in favor of holding the hearing. Any hearing brought pursuant to this subsection shall be held at a time and place deemed appropriate by the department.