CLINTON — Officials of Navigator C02 addressed the county board Feb. 23 about their planned Heartland Greenway carbon dioxide sequestration project, which will include DeWitt County.

James Prescott, of Heartland Greenway, Steve Whittaker, Vault 44.01 geologist and vice president of subsurface, Jennifer O’Keefe, Vault 44.01 manager of land and stakeholder engagement, and Danielle Anderson, of Navigator CO2, presented information about the project to county board members.

Board members Dan Matthews and Terry Ferguson arranged earlier for Navigator to make the presentation.

A pipeline would carry liquified CO2 as a bi-product of ethanol plants located in the Midwest to three wells in DeWitt County, where it would be injected into the ground.  DeWitt County is identified as an area containing optimal geological conditions for CO2 mitigation.

The concept of injecting liquified carbon dioxide into the Earth is one plan to help mitigate the climate change effects of CO2 rather than releasing it into the atmosphere. 

Prescott said extensive geological tests confirmed the Mt. Simon sandstone formation would allow safe, secure and permanent CO2 storage.  Space in DeWitt County will cover about 30,000 acres and include 3-6 injection wells and 6-15 monitoring wells.  The CO2 in injected to a depth of about one mile.

Vault was brought on as part of the project because of the company’s broad depth of experience with carbon sequestration, said Jennifer O’Keefe. 

“We will be injecting over one million tons a year, so we have a lot of experience with other sequestration sites,” O’Keefe said.

Danielle Anderson, with Navigator CO2, said the project’s original route development began in 2020.  The company currently is working on the landowner agreements.

“We, at no time, own the land,” Anderson said.  “We will have a 50-foot permanent easement.”

Landowner agreements will include a permanent easement as well as a temporary easement for construction purposes.  The agreement also will include the company’s response to any issues with the pipeline, including compensation for the landowners.

The company refiled its paperwork for the project with the Illinois Commerce Commission on Feb. 24.  Anderson said the goal was to have one ICC docket open with one timeline filed.

“That starts an 11-month process when the Illinois Commerce Commission will then give us the AOK to construct our pipeline,” Anderson said.

The team said their biggest interest was in ensuring well and storage integrity.

The U.S. Geological Survey (USGS) released a comprehensive assessment of geologic carbon sequestration in 2013, which estimated a mean storage potential in the U.S. of 3,000 metric gigatons of carbon dioxide and a likely storage range of from 2,400-3,700 metric gigatons.

“Illinois has been a focal point for this kind of research for about 20 years,” said geologist Steve Whittaker.  “Archer Daniels Midland has an active site injecting CO2 right now.”

Whittaker said Vault also has worked with several other CO2 wells around the state.

“So, we know quite a bit about the geology here,” he said.

Preliminary site work involves the taking of core samples, seismic surveys, and other evaluations.

“We use all the information to get a picture of what the earth is like below us,” Whittaker said.

The process of drilling the wells includes installing a concrete casting lined with a steel sleeve that will surround each well down to the storage site.

“There are ways of ensuring the wells, and it involves ongoing maintenance,” Whittaker added.