On February 1, 2008, the FAA released a new guidance document: Management of Acquired Noise Land: Inventory – Reuse – Disposal. The document contains information on airport sponsor compliance with Grant Assurance 31, Written Assurances on Acquiring Land. The document includes information on the management, retention and disposal of land acquired for noise compatibility purposes, including criteria for determining whether disposal is required. This guidance follows a 2005 DOT Office of Inspector General audit finding significant violations of Grant Assurance 31.  Kaplan Kirsch & Rockwell has prepared a summary of the guidance.