(a) 
         If construction is not commenced within two (2) years after date of right-of-way grant, the right-of-way may be canceled by the Director of the U.S. Fish and Wildlife Service at his discretion.
     
    
        
        (b) 
         Proof of construction: Upon completion of construction, the applicant shall file a certification of completion with the Regional Director.
     
    [42 FR 43919, Aug. 31, 1977]