Northern Hills Homeowner's Association

60 dnL to be Used as Mitigation Noise Level at MAC

Sep 07, 2000

Published Wednesday, September 6, 2000

MAC begins studying expanded noise, building programs Dan Wascoe Jr. / Minneapolis Star Tribune

The schedule for public comments on proposals for expanded jet-noise mitigation in the Twin Cities area will kick off Oct. 6.

That's when the public will be able to review a proposal that recommends new flight paths, new takeoff and landing procedures and expanded zones where houses might qualify for insulation to muffle jet noise.

If federal aviation officials approve, the proposal could lead to many millions of dollars in additional noise-abatement efforts near
Minneapolis-St. Paul International Airport. About 5,800 houses already have been insulated against jet noise, at an approximate cost of $143 million.

The proposal is being drafted by the Metropolitan Aircraft Sound Abatement Council, which advises the Metropolitan Airports Commission (MAC). A MAC
committee heard a summary of the proposal Tuesday.

It's not yet clear how information about the recommendations will be disseminated, but the advisory group will hold public hearings Nov. 8 and 9 before sending its final report to the MAC. The commission then will send the proposal to the Federal Aviation Administration (FAA), where its fate is uncertain.

Two parts of the proposal will draw particularly close FAA scrutiny because of their potential to set national precedents.

One would expand the area qualifying for insulation from the current average annual noise level of 65 decibels to an area that receives an average of 60 decibels. [ dNL day Night Avg Level ]

The second would seek approval to provide help to buildings exposed to low-frequency noise -- the rumbling vibrations caused by planes on the
runway. Such noise is expected to be a problem when a new north-south runway opens near Cedar Avenue on the airport's western boundary in 2003.

Meanwhile, the MAC is beginning consideration of a $1.2 billion building program for 2001 to 2007. Executive Director Jeff Hamiel said most of the
projects are part of the current $2.6 billion to expand the airport. Other items include pavement repair and other maintenance that would have been
needed even without expansion.

The most expensive items include about $325 million to develop the new north-south runway, $259 million for noise mitigation and $187 million
for a new parking ramp near the Humphrey terminal for passengers and employees.
The structure also is expected to hold a light-rail station for the proposed Hiawatha line, one of two stations that would serve the airport. The
other will be underground at the main Lindbergh terminal.