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Noise Management and Public Response 109 More recently, the FAA has become more rigid in its evaluation of noise abatement proce- dures for the ability to mitigate noise impacts within the 65 DNL contour. For example, a mea- sure may have the substantial benefit of removing low level overflights from a residential area just beyond the 65 DNL contour if the traffic that created those overflights were turned 15 degrees away from the runway heading. Although many might benefit at a level just below 65 DNL and experience many fewer direct overflights, the measure may not be justified if one addi- tional person is exposed to 65 DNL or more as a result of the turn. This situation has been the crux of the evaluation arguments on a number of Part 161 study cases that have been presented to the FAA for review. Local Response The reduction of the size of the 65 DNL contour has led communities into a dilemma of land management and compatibility controls. Two principal ways this has occurred have been through 1) the modification of public expectations for sound insulation programs for those who were within the contour of definition at some time in the past and have come to believe they are entitled to sound insulation that will "fix up" their homes; and 2) the release of areas of vacant and undeveloped land from within the controlled contour area that becomes either eligible for development of, or much more difficult to justify the prevention of, noise-sensitive uses. In the first case, and depending upon the number of units that remain to be sound insulated, airports may choose to continue a preexisting program at their own expense or abandon the pro- gram for those areas that no longer are eligible for federal reimbursement. When programs are abandoned, there is usually a public relations crisis and hard feelings develop that may continue for years. It is usually a better practice to publish only the programmatic boundaries of sound insulation programs that are actively underway and to emphasize in every news release about the program that additional areas may be added as federal funding becomes available. Should the airport sponsor choose to continue a program beyond the 65 DNL contour, only limited federal funding for immediately contiguous areas may be available and the bulk of the excess cost will fall on the sponsor. In the second case, land that has been prevented from incompatible development, but is sub- sequently removed from within the 65 DNL contour by area shrinkage, will often become the focus of new opportunities for the development of noise-sensitive uses. Around many airports, residential developers build up to the contour line. When the contour line retracts, proposals often soon follow to develop additional new residential lands to the new contour line, and so forth. Then, if the character of the airport changes, or if only a couple of new nighttime opera- tions by loud aircraft are introduced, the contour may expand and the new residential develop- ment is again within the contour and the airport often faces a public relations crisis of increasing noise over residential areas and public demand for abatement. Two widely used controls avail- able to the airport to manage this situation are either outright ownership of all the land within the larger 65 DNL contour, or public land use jurisdictional control for non-noise sensitive uses within an area surrounding the 65 contour for the expected worst case condition. Self Assessment Tools for Noise Management Programs As airport managers face the question of whether or not to implement a noise management program, or if one is in place, what its status may be, it is helpful to have an organized way to think through the issues. The preceding sections have provided an overview of the rules, the roles, the responsibilities, and the issues involved in noise abatement and land use mitigation planning efforts, and have discussed the involvement of the public in those efforts. This section