Dr. Schnaar on Geologic Sequestration Permitting
The 2023 Carbon Capture, Utilization, and Storage event will take place on April 25-27, 2023 in Houston, Texas. Gregory Schnaar, PhD, PG, Principal Environmental Scientist, will present on “U.S. Environmental Protection Agency (EPA) Class VI Permit Application Development for Planned Saline Formation Injection Project in San Joaquin Valley, California”. DBS&A Staff Hydrogeologist Daniel Acevedo will also be in attendance.
The event will highlight issues related to subsurface geologic storage and site selection; CO₂ enhanced hydrocarbon recovery and utilization; reservoir modeling monitoring and risk assessment case studies; industry applications; economics, incentives, and policy; infrastructure; environmental, social and governance (ESG) and stakeholder engagement; and machine learning and data analytics applications.
Learn more about DBS&A’s expertise and experience with geologic sequestration, multi-phase fluid modeling, vadose zone and groundwater monitoring programs, and subsurface injection, here.
Abstract
By Gregory Schnaar (DBS&A), Daniel Schwartz (Daniel Schwartz LLC), Stefan Finsterle (Finsterle GeoConsulting, LLC)
San Joaquin Renewables will operate a facility in McFarland, California, that will convert agricultural waste biomass into natural gas and is one of the first facilities to submit a Class VI permit application to U.S. EPA Region 9 for a CO2 injection well. The facility will be located in the San Joaquin Valley in an area recognized by the U.S. Department of Energy (DOE) as an assessed Saline Formation for carbon storage. The planned injection formation is the Vedder Sandstone, which is located approximately 7,780 feet below ground at the project location and dips at a relatively constant four degrees to the west in the vicinity. The Freeman-Jewett, comprised of shale and mudstone, overlies the Vedder sandstone and will serve as the primary seal. Geologic data including acquired seismic profile data and laboratory analysis of archived core samples were used to develop a conceptual model of the proposed storage site and demonstrate non-endangerment of underground sources of drinking water. A three-dimensional static geologic model was developed integrating seismic data and geophysical well data on formation elevations and mapping faults to determine fault type, throw, and formation offset. Vertical fault sealing potential was evaluated based on analysis of the juxtaposition of reservoir and non-reservoir rock and calculation of shale gouge ratio. The conceptual model was used to develop a numerical model within the iTOUGH2 simulation-optimization framework to estimate plume and pressure-front migration and comply with Class VI “area of review” (AoR) delineation requirements. The numerical model incorporated the Vedder formation and several overlying formations, and specific layers were included to represent the separate Vedder shale and sand sub-units. A three-dimensional unstructured grid was developed that allowed for finer grid resolution in the vicinity of the proposed injection well and faults. Several sensitivity analyses were presented in the permit application to assess model assumptions. Supplementary geochemical modeling (PHREEQC) was used to demonstrate that CO2 injection will not cause significant reactions that affect injection or containment. This presentation will focus on lessons learned from implementation of the Class VI required methodologies for a Saline Formation including collection, interpretation, and synthesis of geologic data and modeling results, as well as supplemental analyses incorporated into the application based on EPA’s review.