Does Spokane’s Waste-to-Energy Plant fit into the city’s climate goals?

When Spokane’s Waste-to-Energy Plant was built in 1991, officials argued its construction was essential to stop harmful chemicals from aging landfills from entering the aquifer.

Thirty years later, as Spokane commits to ambitious climate goals on which it has made only marginal progress, city officials still argue that the trash incinerating, greenhouse gas -emitting power generator is better for the environment. Landfills are not only worse for the aquifer, they argue, but also for climate change.

The facility is under the microscope of state leaders, whose new climate-minded cap-and-trade program would hit the incinerator – but, notably, not landfills. When the facility starts having to pay into the cap-and-trade program in 2027, it could come with a cost of $2.5 to $8 million in additional costs for the city each year when it enters the program.

The city successfully lobbied the Legislature this year to fund an emissions life-cycle analysis comparing the facility to landfills, which local leaders believe will show that the incinerator is the most climate-friendly option available for dealing with the community’s garbage.

As waste in landfills decomposes, it produces methane, which is far more impactful on the climate, at least in the short term, according to the EPA. Waste-to-energy facilities, on the other hand, release carbon dioxide and reduce other emissions inside the plant using air scrubbers.

The state estimates that 1.5 million metric tons of carbon dioxide equivalents were produced by landfills in 2018.

Spokane’s Waste-to-Energy Plant is by no means emissions free. According to a recently published city-commissioned report on emissions from 2017-19, the facility is the largest source of emissions produced by Spokane’s municipal government.

The city of Spokane and the community within city limits produced nearly 2 million metric tons of carbon dioxide equivalents in 2019, including government operations, commercial, industrial and residential activities, and transportation. Of that, nearly 100,000 metric tons directly came from the waste-to-energy facility, according to the report.

The report excluded biogenic emissions, which include greenhouse gases that originated from organic materials such as food, plants and other biomass. The report’s authors said biogenic emissions were excluded because they will eventually cycle back to the atmosphere through the same natural processes that produced the vegetation in the first place, though they still contribute to global warming in the meantime.

Including biogenic emissions, the facility produced more than 234,000 metric tons of carbon dioxide equivalents in 2019, which has held steady in the years since, according to the state’s greenhouse gas reporting program.

Landfilling the 276,000 tons of garbage sent to the facility in 2019, generated primarily by Spokane city residents, instead of incinerating it would have directly produced 55% as much nonbiogenic greenhouse gases, according to the city’s report.

That report, however, also estimated the facility indirectly avoided the production of 58,000 metric tons of carbon dioxide equivalents by extracting magnetic metals for recycling and by generating power. That energy would otherwise be produced elsewhere with its own emissions cost, and metals unrecovered from a landfill would be replaced by newly mined material, Spokane Solid Waste Education Coordinator Kristine Major said.

Factoring in these emissions savings, the report found the Waste-to-Energy Plant led to a 24% reduction in life-cycle emissions versus a landfill.

There were other savings not factored in the report, such as the extraction of nonmagnetic metals from the waste ash produced by the facility, which is about 10% of the trash’s original volume and 30% of the original weight.

That ash is transported to a dedicated, lined cell at the Roosevelt Landfill in Klickitat County in south-central Washington, where an electrical current is used to sort the material by density. The metal deposits can then be mined, which is done by a European company, though the city has received a federal grant to explore the possibility of extracting the metal itself, city Public Works Director Marlene Feist said.

The plant produces other emissions that are potentially hazardous, such as fine particulates, carbon monoxide, mercury and dioxins, though at levels well below the permit limits for new facilities, and even further below what’s allowed under the facility’s operating permit.

Tests show emissions of potentially carcinogenic dioxins and furans, which had been a key, early health concern about the facility, at 5% of the EPA standards, and mercury at 2%. Even those low readings remain deceptively high, facility Environmental Manager Jennifer Lennon said, because during annual tests the facility adds half as much activated carbon, which can mitigate those particular emissions to simulate a problem with the system.

“There’s a pump that sucks the carbon out of a bag, and sometimes it gets clumped up, or there’s a bag change and that might get delayed,” Lennon said. “That’s why we test at a lower limit, so we are sure we’re controlling for that.”

The last time the facility was fined for failing an emissions test was in 2010, four years before the city took over operations of the plant. In that case, a facility manager attempted to prove that the facility could pass an annual inspection without any activated carbon, Lennon said. Previous to 2014, the city contracted operations of the city-owned plant to a subsidiary of Waste Management.

“It didn’t work out for him,” she added.

There is one kind of emission from the facility that regularly comes close to reaching permit limitations, however: nitrogen oxides, including nitrogen dioxide. Nitrogen oxides can impact human health, cause acid rain, and contribute to climate change.

In 2022, the facility emitted 83% of the allowable limit under the current permit, and 91% of newer permit standards.

This can largely be blamed on organic waste that could have been composted but was instead thrown into the garbage, Feist said.

Statewide, a bit over 33% of all residential trash between 2020 and 2021 was organic material, according to a state-commissioned survey of a dozen facilities by Cascadia Consulting Group, a Seattle-based firm which also was recently produced Spokane’s latest greenhouse gas inventory.

Of all residential garbage statewide, nearly 11% was once edible food waste, versus about 8.1% inedible food waste such as bones and rinds. Yard and garden waste makes up about 3%.

These proportions weren’t changed dramatically by the pandemic, though recyclable paper disposal soared while wood and construction debris tumbled during that time.

In the report’s eastern region, which included a survey of Spokane’s Waste-to-Energy Plant and a waste transfer station near Pullman, more than 32% of all residential garbage was organic material. This includes about 16% edible food waste, 6% inedible food waste and 4% yard and garden waste.

But the average resident in the eastern region produced more organic waste than anywhere else in the state, throwing away about 170 pounds per person each year, according to Major.

Food waste not only produces nitrogen oxides, it tends to be wet and burn at lower temperatures than other materials, reducing the energy produced per pound, said Kara Odegard, former manager of sustainability for the Spokane City Council.

The city is working to reduce the amount of organic materials that end up at the incinerator, primarily with education campaigns, Feist said. Spokane residents can receive curbside bins for green waste that is composted, but the service is optional and costs residents and about $19 a month from March through November. City officials have considered making the service mandatory.

“We’ve talked about that, but we’re also price sensitive in the city, so the question is, how do we have an affordable service that serves all of our customers?” Feist added.

There could be alternative rate structures to encourage adoption of compost bins, she noted, including by offering a smaller garbage bin paired with an organic waste container for the same price as a larger garbage can.

“We’ve used rate incentives to change habits about water use,” Feist said. “How can we use that model on the solid waste side?”

A better way?

Waste-to-energy is not without its detractors.

Relatively few such facilities exist in the United States compared to densely populated countries such as in Europe, where land constraints make landfills less economically viable. Spokane’s is the only such incinerator in Washington.

Organizations like Zero Waste Europe have urged nations in that continent to move away from waste-to-energy facilities and instead emphasize trash reduction and recycling.

Marco Castaldi, a professor of chemical engineering at The City University of New York and the lead author of the 2021 study “Scientific truth about waste-to-energy,” agrees that reducing, reusing and recycling garbage should be the highest priority, though he argues that waste-to-energy facilities are part of the solution.

“It’s correct that recycling is absolutely preferred over waste-to-energy and over landfilling,” Castaldi said. “No doubt, recycling everything is better, but how feasible is it? Right now, and for the foreseeable future, it is not.”

Zero Waste Europe argues that trash incinerators provide a financial incentive to governments to simply burn recyclable material.

But Castaldi’s study directly contradicts these concerns. Data showed that communities with the facilities, including Spokane, tended to recycle as much or more than their state as a whole.

“We get a bad rap for having this facility and that, ‘Oh, you don’t care about recycling,’ ” Kris Major said. ” ‘You don’t care about it because you need to feed the beast, you want everything to go in the garbage.’

“And it’s like, no, we have always had an excellent recycling program. We recycle things where we’re probably paying more than if we just made it new.”

In the short- to midterm, the choice remains, Castaldi argues: waste-to-energy or landfill.

“It’s great that there are people who are thinking about how to sustainably manage the waste,” he said. “But until we have zero landfilling, all options should be on the table, including waste-to-energy and other new technologies that come up.”

Newer landfills can be designed to capture methane emissions, which also can be used for energy production.

This is still a relatively less commonly used technology, and of 2,600 municipal landfills monitored by the EPA, less than 500 collect methane for energy production.

The EPA estimates another 466 could cost-effectively convert their systems to capture methane.

But even so, landfilling remains the worse option, Castaldi argues, because of the likelihood that not all of the methane could be captured.

Odegard, who expressed concerns about the sustainability of waste-to-energy systems, noted that Spokane’s particular concerns about contaminating its aquifers with landfills remain.

“The way I see waste-to-energy, it’s a bridge technology” on the path to something better, Odegard said.

Evolving technologies could also be used to further limit the emissions from the city’s incinerator, Lennon said.

Practical uses for the waste ash are being explored, such as possibly extracting salts for use in road maintenance. Carbon capture technology potentially could be better implemented at the Waste-to-Energy Plant than in other circumstances, though this prospect is still far off.

“We haven’t hit on that perfect thing, but because our waste-to-energy is a single collection point for a lot of this stuff, we have the ability to use a lot of these technologies,” Lennon added. “We just have to be ready for it.”

Everyone, from those working at the facility, to those who oppose waste-to-energy altogether, agree on one point: The best garbage is the kind that isn’t produced in the first place.

“There is no good way of dealing with garbage, except not to make it,” Major said.