A site plan approval shall lapse and shall become void one year following the date on which approval by the Planning Director, Planning Commission or City Council became effective unless, prior to the expiration of one year, a building permit is issued by the Building Official and construction is commenced and diligently pursued toward completion of the site or structures which were the subject of the site plan. Approval may be extended for an additional period or periods of one year upon written application to the Planning Director before expiration of the first approval. (Ord. 527, 8-4-1997)