(b) An aircraft operator must demonstrate to the satisfaction of the FAA that there has been a change in the noise environment of the affected airport and that a review and reevaluation pursuant to the criteria in §161.305 is therefore justified.
(1) A change in the noise environment sufficient to justify reevaluation is either a DNL change of 1.5 dB or greater (from the restriction's anticipated target noise level result) over noncompatible land uses, or a change of 17 percent or greater in the noncompatible land uses, within an airport noise study area. For approved restrictions, calculation of change shall be based on the divergence of actual noise impact of the restriction from the estimated noise impact of the restriction predicted in the analysis required in §161.305(e)(2)(i)(A)( 1 )( ii ). The change in the noise environment or in the noncompatible land uses may be either an increase or decrease in noise or in noncompatible land uses. An aircraft operator may submit to the FAA reasons why a change that does not fall within either of these parameters justifies reevaluation, and the FAA will consider such arguments on a case-by-case basis.
(2) A change in the noise environment justifies reevaluation if the change is likely to result in the restriction not meeting one or more of the conditions for approval set forth in §161.305 of this part for approval. The aircraft operator must demonstrate that such a result is likely to occur.
(c) A reevaluation may not occur less than 2 years after the date of the FAA approval. The FAA will normally apply the same 2-year requirement to agreements under subpart B of this part that affect Stage 3 aircraft operations. An aircraft operator may submit to the FAA reasons why an agreement under subpart B of this part should be reevaluated in less than 2 years, and the FAA will consider such arguments on a case-by-case basis.
(d) An aircraft operator must demonstrate that it has made a good faith attempt to resolve locally any dispute over a restriction with the affected parties, including the airport operator, before requesting reevaluation by the FAA. Such demonstration and certification shall document all attempts of local dispute resolution.
[Docket No. 26432, 56 FR 48698, Sept. 25, 1991; 56 FR 51258, Oct. 10, 1991]