Underwood Broom Creek Storage Facility #1

The Blue Flint Underwood Broom Creek Storage Facility #1 is a Class VI carbon dioxide geologic storage project developed by Blue Flint Sequester Company, LLC in McLean County, North Dakota. The project is designed to permanently store CO₂ captured from the adjacent Blue Flint Ethanol (BFE) dry-mill ethanol facility near Underwood. The facility will utilize one Class VI injection well (MAG #1), converted from a stratigraphic test well and one dedicated monitoring well (MAG #2). Captured CO₂ from ethanol fermentation will be dehydrated, compressed, and transported via an approximately 3-mile dedicated flowline to the injection site. Annual injection is expected to average ~200,000 metric tons of CO₂, with a maximum anticipated rate of ~220,000 metric tons per year, subject to pressure constraints. CO₂ will be injected into the Broom Creek Formation at depths of roughly 4,700–4,800 feet, a saline formation demonstrated to have sufficient porosity and permeability for injection, while being bounded above and below by regionally extensive, low-permeability confining units (including the Lower Piper–Spearfish formations above and the Amsden Formation below). The approved storage facility covers approximately 4,954 acres, with no known hydrocarbon resources in the storage interval.