Unless a conservation or preservation easement is otherwise modified or terminated according to the terms of the easement or the provisions of sections 76-2,111 to 76-2,118, the owner of the subject real property or the holder of the easement may petition the district court in which the greater part of the servient estate is located for modification or termination of the easement. The court may modify or terminate the easement pursuant to this section only if the petitioner establishes that it is no longer in the public interest to hold the easement or that the easement no longer substantially achieves the conservation or preservation purpose for which it was created. No comparative economic test shall be used to determine whether the public interest or the conservation or preservation purpose of the easement is still being served. No modification shall be permitted which is in excess of that reasonably necessary to remedy the deficiency of the easement.