Spokane’s Waste-to-Energy Plant under scrutiny for greenhouse gas emissions

The mound of trash is piled four stories high, filling one of the bays at the city of Spokane’s Waste-to-Energy Plant.

The bulging garbage bags, tattered textiles, discarded food, and broken furniture and toys represent about four days’ worth of trash from Spokane-area residents.

“I think a lot of people put it out at the curb and forget about it,” said Gina Dempsey, the plant’s manager. The garbage ends up at a West Plains incinerator, where it’s burned to produce electricity.

City officials say the Waste-to-Energy Plant performs a valuable service, consuming 800 tons of trash daily and generating enough electricity to power 13,000 homes. But Spokane’s Waste-to-Energy Plant also has a darker side: It’s one of Washington’s top emitters of greenhouse gases.

In 2014, the plant released more than 105,000 metric tons of carbon dioxide into the atmosphere. It ranks on the lower end of a list of 35 Washington factories, oil refineries, power plants and other facilities that are jointly responsible for 60 percent of the heat-trapping gases released in the state.

Under new rules being developed by the state Department of Ecology, the city would have to cut carbon emissions at the Waste-to-Energy Plant by 5 percent every three years beginning in 2017, or find other ways to offset the emissions.

That’s a tall order for Spokane, which doesn’t have a lot of options for garbage disposal, said Marlene Feist, a spokeswoman for the city’s utilities division.

“I don’t anticipate that we would build another landfill for this community,” Feist said.

The $110 million Waste-to-Energy Plant opened in 1991. It was built to replace a leaking landfill and help protect the Spokane Valley/Rathdrum Prairie Aquifer, the sole source of drinking water for more than 500,000 of the region’s residents, Feist said.

Trucking the city’s waste to a distant landfill would create its own carbon footprint. And there are trade-offs to burying garbage versus burning it, she said. Landfills produce methane, a greenhouse gas that has 25 times the heat-trapping potential of carbon when measured over a 100-year period.

While city officials support the state’s goal of environmental stewardship, Spokane also needs a practical, cost-effective way to dispose of garbage, Feist said.

Given the number of low-income households in the community, “we’d like to keep utility rates affordable,” she said.

The state rules are being developed under Washington’s Clean Air Act at the direction of Gov. Jay Inslee, who has made climate change a centerpiece of his administration but failed to get a cap-and-trade system and carbon tax approved by last year’s Legislature.

State officials said the new rules would gradually reduce carbon dioxide, methane and five other heat-trapping gases that contribute to global warming. Washington is already experiencing the effects of a changing climate through smaller snowpacks, increased flooding and rising sea levels, according to a 2015 report by the University of Washington’s Climate Impacts Group.

The proposed rules apply to facilities that release more than 100,000 metric tons of greenhouse gases annually. In the future, smaller polluters would also have to comply. Beginning in 2020, the compliance threshold would drop by 5,000 metric tons every three years until it reaches 70,000 metric tons in 2035.

The approach isn’t as sweeping as Inslee’s earlier legislation, but the proposed rules still face hefty opposition from Sen. Doug Erickson, R-Ferndale, chairman of the Senate Energy, Environment and Telecommunications Committee. He’s the author of Senate Bill 6173, which would prohibit the Department of Ecology from restricting carbon emissions without legislative action. The bill passed out of Erickson’s committee last week.

Meanwhile, the city has asked the Department of Ecology for flexibility in complying with the proposed rules.

Spokane’s Waste-to-Energy Plant is one of only two in the Northwest, Feist said. The other is in Salem.

Waste-to-energy plants are more common on the East Coast, where there is less space for large landfills.

By virtue of what they burn, the plants are high carbon emitters, said Wayne Krafft, an Ecology Department section manager in Spokane. Items such as carpets, shingles, and the foam found in cast-off couches and mattresses contain high amounts of fossil fuels. Burning food waste, such as bacon grease, also releases carbon, he said.

In terms of greenhouse gas emissions, burning waste is better than burying it, city officials wrote in a letter to the Ecology Department. They cited models developed by the U.S. Environmental Protection Agency, which estimated that sending municipal garbage to a waste-to-energy plant instead of a landfill actually reduced greenhouse gas emissions.

State officials don’t disagree with the models, but said it’s hard to make direct comparisons. Burning garbage releases greenhouse gases into the atmosphere immediately, while landfills release emissions over decades.

In addition, “it really depends on how they manage the methane,” said Neil Caudill, the Department of Ecology’s greenhouse gas reporting specialist.

Many landfills are required to flare the methane produced from the decaying garbage, which reduces greenhouse gas outputs, he said. Some landfills also generate electricity from the methane, which also lowers the impact.

Under the proposed rules, the city has several options for bringing the Waste-to-Energy Plant into compliance, Caudill said. Stepping up recycling efforts to reduce the amount of garbage burned might be the simplest way to reduce carbon emissions, he said.

The city could also buy credits from other polluters who cut their carbon emissions to levels below what the state requires, Caudill said. The Department of Ecology would also accept credits from several out-of-state carbon trading markets.

Earlier this month, crane operator Eric Vangemert sorted the wet garbage out of the refuse coming into Spokane’s Waste-to-Energy Plant. After the garbage dried out, it was headed for nine-story-tall boilers, where it would be burned at temperatures reaching 2,500 degrees. Steam produced by the boilers is forced through turbines, creating electricity.

Employees at the Waste-to-Energy Plant take quite a bit of pride in the work of turning trash into energy, said Dempsey, the plant manager.

“I would love it if more people knew what we do and why we do it,” she said.

This story was updated to correct a figure on the proposed rate of carbon reductions.