An arbitrator to whom a dispute is referred under this subchapter may—
(1)
regulate the course of and conduct arbitral hearings;
 
(2)
administer oaths and affirmations;
 
(3)
compel the attendance of witnesses and production of evidence at the hearing under the provisions of section 
7 of title 
9 only to the extent the agency involved is otherwise authorized by law to do so; and