This article has been corrected to reflect that the contract signed was with Ameresco, the general contractor that contracted for the entire $26 million facility, and which provided other services. Ecoremedy LLC is the subcontractor and supplier of the equipment for the gasification technology, which was supplied to Ameresco under a contract between Ecoremedy and Ameresco.

Contractors hired to help upgrade Edmonds’ wastewater solids handling system are back on site after a five-month hiatus following contractual disputes with the city and state. Nearly two years after the initial expected completion date, city officials say the Edmonds wastewater treatment plant’s new gasification system needs more time – and money – before full completion. 

The City of Edmonds is in the process of drafting an Operations and Management Contract with Ecoremedy, the company providing “Fluid Lift” gasification technology to finalize replacing the city’s 30-year-old sewage incinerator that went offline in 2023. If approved, Edmonds will pay Ecoremedy staff for an additional six months at $149,000 a month, a total sum of $894,000.

This is in addition to a $26 million contract approved by the Edmonds City Council in 2020 with the Washington Department of Enterprise systems, who hired Ameresco to put the Edmonds treatment plant on a path toward more sustainable solid waste disposal. Ameresco then chose Ecormedy to provide the gasification technology. 

Edmonds wastewater treatment plant staff need additional training, Edmonds Public Works Director Phil Williams told members of the city council at a public works committee meeting in October. This is why Williams and others overseeing the project for the city want to keep experts from Ecoremedy around through the rainy season, ensuring technical backup in case things go south during peak flow times. 

The $894,000 price tag pays the salaries of four Ecoremedy employees as they provide Edmonds treatment plant staff with more training, according to city documents. The contract also pays for the city to run additional tests on the gasification system as it goes through changing peak flow seasons. 

These final moves put Edmonds in the home stretch of the project, officials say. On Nov. 30, the Washington Department of Enterprise Systems (DES) determined the commissioning phase to be complete, issuing a “Limited Substantial Completion” letter to Ameresco, Williams wrote via email on Dec. 9. This happens when the new technology runs seamlessly for 120 hours for four consecutive weeks without any interruptions or breakdowns. 

According to previous reporting, the new gasification system initially went online in September 2023, about a year after it was initially supposed to. During commissioning in Dec. 2023, the plant encountered a series of issues including problems with air filters, the conveyance system, dust control issues and leaks in the chemical feed system, according to the city’s Carbon Recovery Project updates. In a domino effect, the gasification system would need to be powered off as other issues were solved.

While the system was down, Edmonds continued to haul its solid waste via rail to a landfill in Oregon, as the old sewage incinerator was no longer in use. In total, Edmonds has spent over $5.2 million on sludge hauling since the project began in 2020, Williams said. 

“It was initially thought that we’d have six months of hauling and we’ve had well over two years,” he told councilmembers at a public works meeting in October. 

In early 2024, there was “little substantial progress towards steady running of the new equipment,” Ross Hahn, Edmonds wastewater treatment plant manager wrote in a January update. 

These issues persisted through April 2024 when “Ecoremedy/Ameresco demobilized from the project due to several contractual disputes and believing they had adequately met project commissioning criteria,” city documents read. “The City and the Dept. Of Enterprise Systems (DES) disagreed with them on these issues.”

Williams didn’t say exactly what those disputes were. 

“It should be noted that as a subcontractor to Ameresco, Ecoremedy contractually satisfied all performance requirements of the project and left with a signed commissioning certificate from Ameresco,” Ecoremedy President and Chief Technology Officer Dave Mooney told MEN. 

During public works meetings, Williams alluded to financial matters being at the root of some of the disputes. 

Throughout construction, Ameresco and the city faced a series of changes to the original contract. However, the initial contract the city entered included a guaranteed maximum price the city was ordered to pay. Any fluctuations in the guaranteed price come out of a contingency fund. 

“We got a bit sideways over some questionable claims that they thought we [the city] should have to pay,” Williams told city councilmembers in October. “…That will all get sorted out at some point,” he said. “Right now that’s not our immediate focus. Our immediate focus is getting the plant started.” 

Additionally, Williams implied that the city and Department of Enterprise Systems believed Ameresco did not sufficiently complete their first shot at commissioning. 

“In April when they left, they felt like they had completed commissioning,” Williams said at another meeting on Oct.18. “That’s likely still their belief today. Luckily it was not our belief and not the belief of the DES.”

During that time, there was back and forth between the parties involved. Eventually DES “layed down the law,” informing Ameresco that their commissioning job wasn’t up to standard. 

In September, “Ecoremedy/Ameresco return for 3-days of Project Chartering meeting with the city and (DES),” according to city documents. “Agreements are reached to recommission the equipment.”

After chartering, Ecoremedy returned to recommission the plant for four weeks. 

“Ecoremedy did so successfully as evidenced by the Limited Substantial Completion from DES and supported by the global engineering firm Jacobs,” Mooney said. “This was done during a bomb cyclone with 12 power outages and during Thanksgiving week, the highest loading week of the year.” 

Williams spoke to the environment at the treatment plant following the hiatus. 

“The mood is a lot better, the vibe is a lot more positive,” Williams told council members at a public works meeting. “I don’t hear people arguing, I hear them problem solving more often than not, and that’s the way it should have been all along. I think we got off track for a bit and people have, you know, bruised egos about that, all of us do, but we’ve got to get over it and deliver.” 

The details of the disagreements will likely be made available to the public once the city and Ameresco wrap up the financial loose ends with the city council at a later date, Williams said in a later interview with My Edmonds News.

ince Ecoremedy’s return in August, the company and the city have run into operational problems having little to do with the aforementioned disputes. In October, a broken chain delayed the project once again before it was fixed a few weeks later, Williams said. 

“The pressure has been on for quite some time now,” Williams said in October. “We’re well behind where we were supposed to be.”

Williams says the complexity of using gasification to handle solid waste at such a grand scale is one of the reasons why the project is taking longer than expected. 

“It’s a proven technology,” Williams said. “Based on all of our comparisons of other possible approaches, it was the cheapest, and initially it promised to save operation and maintenance costs long term.” Over time, the new system will cost less to run on an annual basis than the aging incinerator did, he added. 

Upon completion, Edmonds will be the first municipality in the U.S. to use gasification to dispose of its solid waste on a city-wide level. The cutting-edge technology comes with the promise of almost completely eliminating PFAs, also known as “forever chemicals” commonly found in the air emitted after incinerating solid waste. 

Gasification is the process of feeding incoming solid waste to a high temperature without using oxygen. In the absence of oxygen, the waste breaks down into “energy rich” syngas. Inside the Ecoremedy chamber, the solid waste “self-scrubs” pollutants, resulting in emissions cleaner than those coming from natural gas and propane, according to Ecoremedy’s website. 

The syngas then goes into an oxidizer, beginning a combustion that produces high-temperature, clean thermal energy. After gasification takes place, all that’s left of the solid matter is a charcoal known as biochar. Biochar is high in carbon and can be used as a fertilizer. 

The City of Edmonds is in the early stages of finding ways to sell its leftover biochar, Williams told My Edmonds News  during a tour of the plant in November. 

Screen of the fully automated touchscreen control system that is part of the smart technology used in the new system.After two years of investigation into Ecoremedy’s process, the Environmental Protection Agency ruled in 2022 that the gasification technology did not count as incineration. This officially classified the remaining biochar as a renewable product, which eventually will exempt Edmonds from the EPA’s sewage sludge incineration regulations, according to previous MEN reporting. 

Despite the disputes, Williams deems Ecoremedy as experts in the field and believes the company’s technology will set Edmonds on the path to pioneering the nation into a new age of sewage treatment. 

“The only people that could really teach us how to run their equipment that they developed is them,” Williams said in an interview. “They are exactly the right people to give us the training and the expertise we need to operate at this time… I think they’re exactly the right people to do that. I don’t think anyone else could.” 

— By Ashley Nash