There’s no quiet way to remove a bridge from over Interstate 405 or to move 200,000 yards of dirt to make way for a new freeway onramp.

And all that dirt has to go somewhere. In this case, it’s going just a short distance away – by conveyor belt – to a steep hillside above the freeway near City Hall.

The alternative was taking 10,000 trips by truck to move the earth.

To do that work and much more, the design and build team of what’s known as Stage 2 of the major congestion-relief projects on I-405 has asked for permission to make more noise than is legally allowed under the city’s Noise Ordinance for 319 nights.

The team, I-405 Corridor Design Builders, a joint venture of CH2M Hill and Gary Merlino Construction, has requested the noise variance for the roughly 2 1/2-year lifespan of the project. The dates when the contractor will use those 319 nights weren’t specified, but city officials have indicated they want such information.

A handful of residents voiced their concerns and were given a chance to ask questions of the team at an administrative hearing last week, which was conducted by Neil Watts, the city’s Development Services director.

The neighborhoods that will bear the brunt of noise are in the Talbot Hill area, Rolling Hills, south Renton near City Hall and the edge of Renton Hill just across I-405 from City Hall.

“This is going to be a difficult time for parts of our city,” testified Don Persson, who lives on the part of Renton Hill that likely won’t hear much of the ruckus. He said he’s concerned for his neighbors.

Watts has 10 days to make his decision on the variance; he’ll likely grant the variance, but the tough part is what conditions to place on the work to protect the public’s eardrums and still get the work done in a timely fashion.

Broadly, noise walls will protect two neighborhoods, Talbot Hill and Rolling Hills, from much of the noise. The walls really are designed to block freeway noise, but their construction schedule has been sped up to do double-duty as barriers to the project’s noise.

The builders took pains to explain the project at the hearing and met with residents in the field to outline what they will see over the next few months.

What Susan Giger heard didn’t make her feel particularly comfortable. She has lived in her house on Cedar Avenue since 1973. The builders are documenting through photos any existing cracks in the foundation of her home and others on the street.

She was told this is in the event of the “worst-case scenario” and the fill work damages the foundations. Big machines will compact the soil.

Besides some peace of mind, the Giger and her neighbors will lose something else precious – a wall of maples and other trees on that steep slope that breaks the noise from I-405.

“We are going to lose all our trees and the wildlife,” Giger said. It’s not unusual to see deer, raccoon, possums and the occasional eagle in the woods.

But what happens next to the slope also concerns some residents, including the possibility that new homes will be built.

The fill will come level to Cedar Avenue – a dead-end street – and extend out more than 100 feet.

“It doesn’t take a rocket scientist to figure out this one,” said Terry Stange. “It will be developed.”

Gary Merlino Construction, the main construction contractor for the I-405 Stage 2 project, had a preliminary plat to build homes on two tiers on the hillside a few years ago. However, that project never got off the ground, Watts said.

Now, as part of the I-405 project, the company will get another chance, by filling in the hillside. Merlino is doing the work without city oversight because the hillside is in the I-405 right of way and thus within the jurisdiction of the state transportation department, according to Watts.

The state now owns the hillside but will move the line designating the right of way closer to the freeway once the I-405 project is complete and likely transfer the property back to Merlino so that it can be developed, Watts said. The city then would have control over how the hillside is developed, he said.

First, the builders, in cooperation with the Washington state Department of Transportation, have a major multimillion-dollar project to complete.

I-405 through Renton is the most-congested stretch of freeway in the state, with backups occurring for about 12 hours a day.

The Stage 2 project will add an offramp from southbound I-405 to Talbot Road and an onramp from Talbot Road to northbound I-405. The work will require replacing the Benson Road bridge over I-405 so a new lane can be added to the freeway in each direction. Benson Road will undergo a major overhaul, too.

Benson Road won’t close during the project, but some lanes will close during the day.

The I-405 project team made its case for the variance at a July 7 hearing. Anyone who disagrees with Watts’ decision must file an appeal within 14 days.

Much of the presentation was done by Alan Brown, project manager for

I-405 Corridor Design Builders. Work will begin this month and the entire project will be completed in August 2011.

Brown explained that the team originally planned to ask for 353 days in the noise variance. The number of days was reduced after reviewing the workflow, but still keeping an eye on doing work at night that if done during the day could make congestion worse on the freeway.

The freeway will close totally at night on a weekend to allow for the removal of the Benson Road bridge and then again when new bridge girders are placed.

The builders offered a number of ways they plan to control noise and to handle citizen complaints, if they occur. Besides the noise walls, the mitigation measures include:

• Communication with the public through direct mail or at community meetings.

• A noise hotline that a supervisor will answer. The team is promising an individual response to each complaint, rather than taking a “broad-brush” approach.

• Secure tailgates

• Turn off equipment

• Leave up natural barriers, such as trees.

The No. 1 complaint is the incessant beep beep beep that’s heard when equipment backs up. There’s a way to tone down that noise, too.

“If it’s noticeable and causes a problem, we will deal with it,” said Gene Peterson, an environmental compliance officer with I-405 Corridor Design-Builders.

Persson, also a member of the Renton City Council, offered some other ideas, including:

• Specific days for when the variance is needed. Typically, the variance is required between 10 p.m. and 7 a.m.

• Work stoppage if certain noise levels are reached.

• Motel voucher for those particularly disturbed by the noise.

• Flaggers instead of the back-up beeper.

• A variance of one year but renewable.

• A penalty if the noise exceeds what’s allowed in the variance.

Dean A. Radford can be reached at 425-255-3484,ext. 5050.