Class VI Permitting, CARB Certification, and Monitoring Program
As part of a multi-organization team, Trihydro supported permitting efforts and led baseline environmental monitoring for a carbon capture and sequestration (CCS) project in EPA Region 7.
Working with PureField Ingredients, an ethanol producer, our role included preparing a Class VI underground injection well (UIC) permit application and a California Air Resources Board (CARB) certification package. We developed the surface and shallow monitoring program and are actively conducting monitoring to establish a clear understanding of site conditions.
Implementing the Testing and Monitoring Program
The monitoring program includes eco-vegetation, soil efflux, soil gas, passive seismic, and groundwater sampling. The eco-vegetation survey, supported by remote sensing, is based on a digital vegetation map verified by field ecologists. Soil efflux measurements establish baseline CO₂ flux rates across the project site. Soil gas and groundwater programs combine routine grab samples analyzed in laboratories with continuous sensor data collected remotely. Annual satellite imagery also tracks vegetation changes that could indicate potential CO₂ leakage.
Developing the Class VI UIC Permit Application and CARB Certifications
Trihydro worked with PureField Ingredients and mutipel other stakeholders and project developers over four years to usher the Class VI permit through multiple rounds of revisions, responding to EPA comments, and being present for the public comment period. Additionally, Trihydro is helping draft the California Air Resources Board (CARB) certification packages.
Permit Approval and Injection Commencement
On April 10, 2026 the EPA Region 7 granted PureField Ingredients the authorization to inject (ATI) at their Russell, KS ethanol facility. On April 13, 2026, injection began, marking PureField Ingredients as the first project in EPA Region 7 to be granted an ATI for a Class VI CO2 injection well, the first of its kind in Kansas, and among the first tied to a food and biofuels platform. Trihydro continues to be a part of the ongoing shallow monitoring and CO2 injectate sampling as required by the permit conditions.
Now that the Class VI permit is approved, monitoring data, combined with CO₂ injection information, will be used to meet multiple regulatory and reporting requirements, including Class VI standards, the Subpart RR monitoring plan, the IRS 45Q tax credit program, and CARB’s low-carbon fuel standard (once CARB is approved. Trihydro is integrating this data into a secure web-based management system to support long-term tracking and compliance.
