95-6 Evaluating Legacy Wellbores for Class VI Permits in Wyoming

Session: Sustainable Subsurface Pore Space Utilization: Site Selection, Characterization, and Modeling

Presenting Author:

Authors:

Abstract:

Class VI permits require evaluating legacy wellbores in the Area of Review (AOR), which is critical for assessing potential risks to groundwater resources.

Our presentation details the process of gathering information and assessing data from hundreds of legacy wellbores at the Northern Powder River Basin Carbon Sequestration Hub in Wyoming for Class VI permit requirements and as part of the CarbonSAFE program. We introduce a novel, phased corrective action plan that combines prioritized well plugging with a tailored monitoring program. Due to limited regulatory guidance, we developed well-specific evaluation criteria informed by plugging records and pressure rise analyses. This customized approach applied to a large AOR creatively meets compliance standards, reduces corrective action costs, and reduces operational risks.

The presentation demonstrates how a strategic, phased wellbore evaluation methodology can streamline regulatory compliance, enhance environmental protection, and provide cost-effective corrective action solutions for operators. This work offers actionable insights for regulators, environmental professionals, and industry stakeholders to lay the groundwork for improved best practices in managing legacy wells and corrective action requirements under the underground injection control (UIC) Class VI framework.

Geological Society of America Abstracts with Programs. Vol. 57, No. 6, 2025

doi: 10.1130/abs/2025AM-6354

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