EVERETT, Wash. (AP) - Just north of a Washington state residential development is an old Everett landfill. At either end of the decommissioned landfill are two fans, sucking methane gas emitted from the decomposing site, and pushing it through steel pipes.
Nearby is a six-phase development along the Snohomish River which includes 1,250 multi-family units, a theater, grocery, hotel, office building and potentially a medical clinic.
The city operated the landfill from the early 1900s until 1974, when the area was decommissioned and covered by a 12-inch (30-centimeter) layer of soil.
"It was your run-of-the-mill landfill site that accepted all kinds of man-made waste," Everett Associate Engineer Randy Loveless said.
Developer Shelter Holdings bought the land and began building on the site in 2019.
"It seems crazy," Loveless said. "But it’s one of those deals where with careful design and planning you can do it in a way that’s not just safe but restores that area to a condition that’s better than when it was left."
The property is expected to release small amounts of methane for years, but the production rate has slowed substantially and likely will continue to diminish over time.
The landfill currently generates methane at about 15% of its peak in the 1970s. By 2030, the amount is expected to drop to 10%.
In December, the city council approved a $150,000 contract funded by Everett and the state Department of Ecology to maintain the fan system for the next three years.
Much of the system has been in place for nearly 20 years, but the city is improving and adding capacity as the development grows.
"It’s a way of sort of recycling a part of our community that has been discarded," Loveless said.
This article has been updated to identify the precise location of the former landfill.