Wet Cake Is Next Phase in AltEn Cleanup

MEAD, Neb. (DTN) -- The company leading the environmental cleanup at a closed Nebraska ethanol plant on Tuesday detailed plans for a pilot project to move as much as 24,000 tons of contaminated piles of distillers grain to a landfill.

NewFields, an environmental cleanup firm overseeing the AltEn ethanol plant, will start a new phase of cleanup in September to remove the distilled grain, or wet cake, after consolidating roughly 115,000 tons of wet cake still stored on the ethanol plant's property. The sheer volume of wet cake has been a major challenge in cleaning up the site.

The AltEn ethanol plant just south of Mead has been shut down since February 2021 following numerous environmental violations reported by the Nebraska Department of Environment and Energy. AltEn promoted the idea of accepting unsold treated corn seed from major companies but began stockpiling the contaminated wet cake on site after it was considered unfit for livestock feed or as a soil conditioner. The wet cake and ponds filled with pesticide-contaminated water on the site combined to create an environmental disaster for the neighboring residents.

WHAT HAS BEEN DONE

NewFields has consolidated the wet cake and constructed a berm around it. NewFields also covered it with a "post-shell" to reduce stormwater runoff from the wet cake and to reduce odors from the wet cake that had sparked some of the initial complaints against AltEn going back to 2019. In placards detailing their project, NewFields stated the wet cake has a high volume of water, but total pesticides equal only 0.025% of the actual weight of the wet cake.

"The wet cake is non-hazardous waste, in accordance to a regulatory definition," said Bill Butler, a senior engineer with NewFields, adding testing on the wet cake is done by a third party.

NEXT PROCESS

The wet cake will go through a "solidification" process, which includes blending it with a clay material in a large horizontal mixer. The solidification will reduce the moisture content and make it easier to haul and store in the landfill.

The pilot project will lead to hauling the 24,000 tons to a Waste Management Inc. landfill about 24 miles away. The objective is to determine if processing and hauling the wet cake to a landfill is the long-term solution for removing all the wet cake on the site.

"There are a lot of things we need to learn -- how much to mix, how variable is the material, how quickly can we mix it, how quickly can we load and transport, and how quickly can get it to the landfill," Butler said. "We're going to get a lot of information. While our target is to get 24,000 tons, we may get less than that, depending on how things go."

Asked about other ways to possibly destroy or remove the wet cake, Butler said NewFields had looked at incineration as an option, but no companies are doing that now.

STORMWATER, DUST AND ODOR MANAGEMENT

As part of opening up the wet cake piles and churning them around, Butler said the project will require close attention to stormwater management, as well as keeping down the dust and odor that will come from loading and moving high volumes of material. Odor could remain one of the biggest challenges, and area residents could notice that as soon as the moving begins. Butler said the company will be applying an odor suppressant to try to manage it.

"We know as soon as we start moving this material around, disturbing everything again, we're going to get odors, and it's very challenging. There's not a lot we can do to manage the odors," Butler said.

Workers at the site who will be moving the wet cake every day will wear personal protective equipment (PPE). He said that will be done mainly for personal hygiene reasons.

Don Gunster, a partner and environmental scientist with NewFields, added that the company will look to halt hauling material during Friday night football games at the local school and other events as well to avoid conflicts with the community.

There are multiple air monitors around the site that will test the air quality.

Waste Management also conducted its own testing to ensure they can accept the wet cake. Mike Hey, an area manager for Waste Management, said the company's local landfills are used to accepting wet cake. The challenge here is the sheer volume involved.

OTHER PREPARATIONS TO MOVE THE MIX

Waste trucks hauling the wet-cake mix will have plastic liners inside them and will be covered as well. The trucks will then be washed before they leave AltEn to avoid getting any material on public roadways.

Asked about the layers of protection to handle the wet cake and haul it, Butler said a few requirements were set by state regulators largely around managing stormwater risks. "A lot of it is just taking precautions just like you do with any of these types of cleanup projects," Butler said.

It will also require a lot of frequent hauling back and forth to the landfill about 24 miles away. Hey said each truck would haul 20-24 tons, and he expects there will be 60 loads a day that will come out of the AltEn facility. If the project goes as planned, that would come out to about 1,000 loads.

NewFields and FRG will haul the wet cake until sometime likely in November when temperatures become too cold to manage the materials. Then they would start back up next spring, Butler said.

AltEn's owners walked away from the cleanup, leaving major seed companies that delivered treated corn seed to the plant to form the AltEn Facilities Response Group (FRG) to clean up the distilled grain and wastewater ponds on the site. Those companies include AgReliant, Bayer, Becks, Corteva Agriscience, Syngenta and Winfield United.

Since FRG and NewFields took over, the companies have worked to reduce the volumes of water in storage ponds, treated as much as 49 million gallons of water, and applied 30 million gallons of that water on area farm fields.

GROUNDWATER TESTING

Talking about groundwater testing, Butler said testing done off-site has not discovered any groundwater contamination. On the AltEn site, one well has tested positive for two pesticides, which Butler said likely come from one of the lagoons. The pesticide levels are "below EPA levels."

Representatives from the group met with reporters Tuesday afternoon and planned to hold a presentation and open house with residents around Mead on Tuesday evening as well.

As DTN reported earlier, FRG so far has spent more than $28 million on the cleanup and has filed a lawsuit to freeze assets for AltEn and some related companies tied to the original owners. Bayer, in a recent court filing, accused Tanner Shaw, the former president/owner of AltEn, of moving assets around to try to avoid paying for the cleanup.

See "Bayer Fights to Force Owners of Defunct Ethanol Plant to Cover Cleanup Costs" here: https://www.dtnpf.com/….

Chris Clayton can be reached at Chris.Clayton@dtn.com

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