Complaints about overuse of the new third runway are based on community misperceptions, Sea-Tac International Airport director Mark Reis said Jan. 8 at a special Highline Forum meeting.

Reiss cited the runway's final Environmental Impact Statement, which said, "Its primary purpose would be to enable two separate arrival streams to Sea-Tac during poor and good weather, thus increasing the efficient operating capability of the Airport during peak periods."

But Des Mayor Bob Sheckler, Forum cochairman, said community leaders had been told repeatedly that the third runway would be used primarily for arrivals during bad weather.

"I believed it and now you are saying something different," Sheckler declared. "To be honest with you, that's what was said."

The Highline Forum was formed by officials from the Port of Seattle, the Highline School District and the cities of Burien, Normandy Park, Des Moines, SeaTac, Tukwila and Federal Way to discuss subjects of mutual interest. The Port operates the runway.

The special meeting to discuss community concerns about the new runway had been set for Dec. 18 but was postponed because of snow.

Responding to questioning from Sheckler, Reis said the new runway will be used as a "fully functioning runway."

Reiss also said the Port considers mitigation for the runway is complete, pending a Federal Aviation Administration noise impact study.

The process, known as a Part 150 study, will begin in November when the Port has enough data to determine noise impacts from the runway, according to Reis.

Based on the findings, more money may become available for more noise insulation for homes, Reis said.

However, the airfield will be used differently from April through October when the first runway will be closed for repaving. That will add to the challenge of assessing noise impact, he noted.

Sheckler said it could take three years before the Part 150 process is completed and five years before additional mitigation is done.

Reis said some changes could be made before the study is completed. But receiving funds from the FAA for insulating homes will have to wait until the study is completed.

Based on projections of third runway noise, the Port bought 64 homes and relocated residents in the north approach transition zone, sound insulated 87 homes in the north, and directionally sound insulated 27 homes.

While the Port operates the airport, the FAA actually manages air traffic and the use of the runway, Reis noted.

Outlining the FAA's runway plan, Reis reported the third runway will be utilized minimally from 10 p.m. to 6 a.m.

During normal conditions, the first runway will be the primary runway while during low visibility conditions both the first and third runways will be used with the second runway used primarily for departures.

During heavy traffic periods, the third runway will also be utilized, Reis noted.

Officials had estimated the third runway would handle 27.7 percent of the air traffic throughout the year, according to Reis.

"There was never any commitment that would be the number," Reis added. "That was a best guess."

Even during last week's rainy weather, third runway usage was only been in the 30 percent range, Reis noted.

"We've seen an evolution with traffic controllers on how they use the runaway," he said.

As part of it's third runway action plan, the Port will establish a communication working group with the FAA, post runway use and noise data on the Port's Web site, use portable monitors to obtain noise data and implement a community outreach plan.

Tukwila Mayor Jim Haggerton noted that with so much public outcry over recent runway use, "I can't imagine what will happen April 1" when the first runway is shut down.

Haggerton said Port officials had never mentioned to local leaders that the first runway would be closed before commissioners voted to repave it.

Reis responded that the repaving had been in the Port's capital development plan for ten years.

Noting that the third runway was projected to open in 2001 and then again in 2004, Reis said the other runways had been used more than anticipated.

The first runway is in such bad shape, it needs to be repaired soon, Reis added.

Reis also noted that the second runway could be repaved in 2010 as part of a federal stimulus project.

State Sen. Karen Keiser (D-33) said the third runway permits were granted on the basis that it would be used primarily during bad weather.

"I'm concerned what this does to the process," Keiser declared. "Why go through it, when it will change?"