South Metro Airport Action Council
** S M A A C **

Public Announcement/Press Release Dateline: 24 February 2003 Minneapolis, MN
Citizen's Group Says New Noise Map Lacks Credibility

The South Metro Airport Action Council (SMAAC) found that the new "mitigated noise exposure map" released last week by the Metropolitan Airports Commission (MAC) glosses over misstatements and undisclosed assumptions. "Technical terms, and common terms interpreted differently than ordinary usage, challenge public debate about airport noise." SMAAC announced. "MAC falsely represents past, present, and future noise exposure as is apparent by simply comparing their own maps." The public often hears that aircraft noise is being abated by manufacturers and by airline retirements of older airliners. While it is true that new aircraft are somewhat less noisy, the gains forecast were not realized. More and different operations than forecast resulted in far more noise exposure than either the "official 1996" forecast map or the new 2007 forecast map show. "Actual noise exposure maps prepared for the 1998 EIS and the Part 150 Update withdrawn for 2001 prove that forecasts and other inputs to the computer model missed, literally, by a mile." SMAAC said. "We were rebuffed by MAC when we noted that maps based on actual operations showed airliner changes, which rarely occurred when forecast anyway, were overwhelmed by more flights and more variations in where they flew." Noise exposure counts the people overflown, and more flights require approachin g and departing aircraft to fly over new areas. And so will the new runway. "The noise map based on 2002 use and an unlikely operations plan for 2007 undoubtedly misrepresents noise exposure and arbitrarily makes thousands of people ineligible for any relief." according to SMAAC. "Noise exposure has increased, not abated, around MSP by increased daily use of Stage 2 aircraft and more flights of all kinds since 1996, the last time noise exposure was mapped." Homes in the new 60 DNL areas were projected in 63 DNL areas in the old map and shown fairly often in, or on the fringe of 65 DNL areas in EIS maps. Some residents in Mendota Heights also noted that the 1996 forecast map (analogous to the 2007 base map this go-around) did not correctly model MSP operations, and therefore could not predict noise exposure even within its margin of error (resolution). SMAAC says this situation is similar and familiar.

"Hidden in the computer inputs, in both cases, is a hoped-for at best, lied-about at worst, plan for runway uses and operations." SMAAC said. "Commissioners did not discuss this aspect of drawing the noise exposure maps, nor consider that historically operational assumptions were impossible to implement." In a letter to FAA, endorsed by Senator Dayton, SMAAC asked if Federal regulations required Part 150 plans to be based on "safe and feasible" operational plans. The answer was neither "Yes." or "No." FAA said that because by regulation "significant (increasing or decreasing noise exposure) operational changes" require noise exposure plans (Noise Compatibility Programs) to be amended to the new situation. SMAAC is contesting the process for maintaining, as well as the propriety of, the Minneapolis-St. Paul Airport (MSP) Noise Compatibility Program. Thousands of people were exposed to excessive noise because noise abatement measures were not realized or, more likely, falsely projected. Public attention has been drawn to the noise mitigation projects undertaken since the requirement for a MSP Noise Compatibility Program was imposed on the Metropolitan Airports Commission (MAC) by the Minnesota legislature in 1996; and, on the Federal Aviation Agency and the MAC by the Final Environmental Impact Statement (FEIS) in 1998. The current update would be a relatively minor adjustment, focused on any excess noise and non-compliant use of MSP compared to operations during 2001. It isn't, because the for-2001 (1996 base year) noise exposure map was withdrawn. Noise abatement was, is, and likely will be, far less than projected in the now 10-year-old plan. Non-compliant use was, and will be, far greater than projected. In the case of the just-released Update, the MSP Noise Compatibility Program over-estimates noise reduction under the parallels, because it will be extremely difficult to impossible to divert as many aircraft as projected onto the new runway. Stated as per cent of all flights, diversion is, of course, as wrong as the projection of total flights.

For further information, contact Jim Spensley at 612/824-9988 or email

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