No person may excavate or remove any material from lands within 250 feet of the centerline of the Tanana Levee structure; except, that excavation and removal for the purpose of constructing foundations for buildings or other structures upon the excavation is permitted. Such excavation shall be backfilled to original ground elevation within 90 days from the date excavation began. (Ord. 2009-55 § 2, 2010; Ord. 85-124 § 3, 1985. 2004 Code § 15.04.130.)