Class VI Case Study

The Illinois Basin Decatur Project injected approximately 1 million metric tonnes of CO2 derived from biofuel production into a saline reservoir in Decatur, Illinois. Operational injection started in November 2011 and was completed in November 2014. The project effort is currently conducting post-injection monitoring.

Map highlighting locations of field tests for early validation and development phases in the Illinois Basin Decatur Project., adapted from
Map highlighting locations of field tests for early validation and development phases in the Illinois Basin Decatur Project.

The wells injected CO2 into the Mount Simon Sandstone, the primary carbon storage resource in the U.S. Midwest with potential storage volumes in the range of 12 billion to 172 billion metric tonnes of CO2. The Eau Claire Formation serves as the primary cap rock preventing upward migration through the strata. The shallower Maquoketa and New Albany shale formations further separate the injection formation from the surface as secondary and tertiary confining zones.

Decatur project seismic
The Illinois Basin Decatur Project developed and implemented a rigorous and extensive monitoring, verification and accounting program, including high-fidelity induced seismicity monitoring, 3-D seismic surveying and 3-D vertical seismic profiling.

As part of a complete CO2 monitoring program, the facility combines subsurface and near-surface monitoring techniques. Geophysical surveys monitor the cap rock, and equipment monitors temperature and pressure in the injection zone. Near the surface, soil and groundwater sampling monitors for changes in dissolved CO2 in the area above the injection zone. Data collection covers 24 months of pre-injection baseline, 36 months of operational injection, and up to 10 years of post-injection monitoring.

Citations

1. Global CCS Institute. 2017. Illinois Industrial Carbon Capture and Storage Project. Retrieved 2/26/2017 from https://www.globalccsinstitute.com/projects/illinois-industrial-carbon-capture-and-storage-project

Images: “Emma Township pumpjacks” by Nyttend; “Decatur project seismic” by DOE