(289g) Research and Development of Carbon Capture and Storage in the Illinois Basin

The Illinois Basin has hosted numerous research and commercial carbon capture and storage (CCS) projects over the last two decades, many led by the Illinois State Geological Survey (ISGS). These projects include the world-renowned Illinois Basin – Decatur Project (IBDP), multiple U. S. DOE-funded Carbon Storage Assurance Facility Enterprise (CarbonSAFE) projects across Phases I, II, and III, and several commercial projects of varying scale. Current CCS research in the Illinois Basin is focused on further geospatial and petrophysical characterization of recognized storage reservoirs and sealing horizons, as well as identification of additional units with potential storage and sealing properties. While the geological and industrial setting appears favorable for commercial-scale CCS development, remaining challenges include underdeveloped transportation infrastructure, fledgling regulatory frameworks at the municipal, county, and state levels, and negative public perception.

The Illinois Basin is a structural and sedimentary basin underlying approximately 80,000 square miles of Illinois, southwestern Indiana, and western Kentucky. It is elliptical, with the long axis trending NW-SE and deepest in southeastern Illinois and southwestern Indiana. The Illinois Basin is situated favorably for CO₂ supply, being in the heart of ethanol production in the Midwest U. S. and is near three major metropolitan areas and their associated industries: Chicago, St. Louis, and Indianapolis. However, capture and storage studies are not limited to ethanol. For example, the UIC Class VI permits issued to Wabash Carbon Services (WCS) are for storage of CO₂ from the Wabash Valley Resources (WVR) ammonia gasification plant near Terre Haute, IN. The ISGS is also currently studying storage potential for sites at or near coal-fired power plants and cement production.

Geologically, the Illinois Basin comprises multiple storage complexes suitable for carbon storage, particularly in the Cambrian and Ordovician strata deposited atop the Precambrian basement rock. These storage complexes leverage several units with favorable reservoir characteristics, including the Mt. Simon Sandstone, the Potosi Dolomite, and the combined St. Peter Sandstone and Everton Dolomite. The Illinois Basin also has multiple sealing formations, including the Eau Claire Formation, Maquoketa Group, and New Albany Shale Group. Additional units are being characterized for storage or sealing properties, such as the New Richmond Sandstone as a potential storage reservoir.

To date, the U. S. EPA has granted four Underground Injection Control (UIC) Class VI permits to construct injection wells for the geologic storage of CO₂ in the entire U. S., all four of which are in the Illinois Basin and in EPA Region 5. Two permits were issued to Archer Daniels Midland Company (ADM) in Decatur, IL. The first was issued for CCS1, the CO₂ injection well for the IBDP, a demonstration project which successfully injected and stored one metric megaton of CO₂ in the Mt. Simon Sandstone from 2011 to 2014.

The IBDP site is now in its post-injection site care (PISC) period, continuing with a prescribed monitoring program detailed in the Class VI permit. The Illinois Industrial Carbon Capture and Storage (IL-ICCS) project built off the learning from the IBDP and was issued a Class VI permit to install an injection well (CCS2) roughly 0.6 miles from CCS1. The IL-ICCS project is active and to date has stored over two metric megatons of a permitted six metric megatons of CO₂ in the Mt. Simon Sandstone. The primary seal for both wells is the Eau Claire formation, and the Maquoketa Group, a regionally continuous and thick caprock unit which acts as a secondary seal.

Two Class VI permits were issued by the U. S. EPA in January 2024 to WCS to allow the construction of injection wells for the injection and permanent storage of up to twenty metric megatons of CO₂ in Vermillion and Vigo counties in Indiana. Now in its “pre-operation” phase, the WCS project intends to inject into the Cambrian Potosi Dolomite, which demonstrates significant vugular porosity and is a known potential lost circulation zone in the Illinois Basin. The primary seal is the Maquoketa Group. In addition to the permits granted to ADM and WCS, twenty-two additional permit applications are under review by the U. S. EPA, e. g., three Class VI permits applied for by One Earth Sequestration for CO₂ storage near their ethanol production facility in Gibson City, IL.

The geological and industrial advantages of the Illinois Basin present a uniquely promising environment to develop commercial-sale CCS to an extent that can help mitigate climate change. However, challenges to acceptance and implementation remain, particularly in the areas of regulation and public approval. Ongoing research by the ISGS is focused on identifying and characterizing new geologic formations suitable for the permanent storage and containment of CO₂, providing risk-based assessment of capture, transport, and storage potential, and increased stakeholder education and interaction.