Carbon Capture & Storage (CCS) /
Carbon Capture, Utlization & Storage (CCUS) Consulting
A&A's Complete Carbon Capture, Utilization, and Storage Consulting Practice — CO₂ Enhanced Oil Recovery, Dedicated Geologic Storage Site Characterization, Well Integrity and Regulatory Support, and Monitoring, Reporting, and Verification — Worldwide
Assign your company's CCS/CCUS project — CO₂ enhanced oil recovery (EOR), dedicated geologic CO₂ storage in a depleted or depleting oil and gas field or a deep saline formation, Class II/Class VI well-integrity and regulatory support, or any combination of these — to A&A, and let the high-level, seasoned CO₂-EOR and CO₂-storage consultants of the A&A Consulting Team put more than five decades of hands-on CO₂ experience to work for you, around the world.
Avasthi & Associates, Inc. (A&A) is an independent petroleum engineering and geoscience consulting firm. A&A does not sell CO₂, injection equipment, monitoring technology, or carbon-credit/offset products — our only business is expert technical consulting, which means A&A's CCS/CCUS recommendations are never influenced by a stake in any particular vendor, technology, or carbon-market program.
Carbon Capture, Utilization, and Storage (CCUS) — and Carbon Capture and Storage (CCS), the subset of CCUS that does not include a utilization step — captures CO₂ from an industrial or power-generation source before it reaches the atmosphere, and either puts it to productive use or permanently stores it deep underground in a suitable geologic formation. Several high-level, seasoned consultants of the A&A Consulting Team are subject-matter experts (SMEs) on CO₂ injection for both EOR and CO₂ storage/geosequestration, and have been working on CO₂ projects, around the world, since the 1970s.
A&A's CCS/CCUS Consulting Services
A&A's CCS/CCUS practice is organized into the following four consulting services, each with its own dedicated page describing A&A's methodology, project experience, and deliverables in depth:
1. CO₂ EOR + Geosequestration (CCS/CCUS) Consulting
A&A's full CCS/CCUS practice service — site screening and storage characterization, CO₂ injection and storage engineering/modeling/simulation, Class II/Class VI well design and regulatory support, and monitoring, reporting, and verification (MRV) — covering CO₂-EOR, dedicated geologic storage, or both, from initial project feasibility through long-term project surveillance.
2. CO₂ Storage in Depleted / Depleting Oil and Gas Fields
Dedicated site characterization, legacy well-integrity evaluation, and storage-performance modeling for CO₂ geologic sequestration in a produced reservoir — a storage setting that offers a proven trap, extensive pre-existing subsurface data, and, in many fields, continuing CO₂-EOR synergy, but that requires careful evaluation of legacy well integrity.
3. CO₂ Storage in Deep Saline Formations
Regional-scale site characterization and storage-performance modeling for large-capacity CO₂ geologic sequestration in a deep saline formation — the storage setting offering the greatest capacity and widest geographic availability, generally starting from a less mature subsurface base, and requiring independent analysis of the four CO₂ trapping mechanisms (structural/stratigraphic, residual, dissolution, and mineral trapping) in the absence of a prior hydrocarbon accumulation.
4. CO₂ Injection Wells: Class II vs. Class VI Wells
Life-cycle well-integrity due diligence and regulatory comparison between the two U.S. EPA Underground Injection Control (UIC) well classes relevant to CO₂ projects — Class II (CO₂-EOR) and Class VI (dedicated CO₂ storage) — including well-status evaluation, workover assessment, and new-well program development, applicable to CO₂-EOR and dedicated-storage projects in either storage setting above.
How A&A's CCS/CCUS Services Fit Together
Every CCS/CCUS project ultimately turns on a small number of linked decisions, and A&A's four services are built to support them in sequence:
• CO₂-EOR versus dedicated storage: whether injected CO₂ is used to recover additional oil (CO₂-EOR, regulated as a Class II well) or stored with no utilization step (dedicated geosequestration, regulated as a Class VI well) — many projects pursue CO₂-EOR first and evaluate dedicated storage later in the same field, which A&A's CO₂ EOR + Geosequestration (CCS/CCUS) Consulting page addresses in full
• Choosing a storage setting: for a dedicated-storage (or eventual dedicated-storage) objective, whether the target formation is a depleted or depleting oil and gas field or a deep saline formation — each presents a distinct technical profile, addressed in A&A's two dedicated storage-setting pages
• Well classification and regulatory planning: regardless of storage setting, existing and planned wells need evaluation against Class II and/or Class VI construction and integrity standards, particularly where a project may pursue dedicated storage after starting as CO₂-EOR — addressed in A&A's Class II vs. Class VI Wells page
• Monitoring, reporting, and verification (MRV): every CCS/CCUS project needs an MRV plan consistent with applicable federal and state requirements, and ongoing reservoir, plume-migration, and wellbore-integrity surveillance through the project's injection and post-injection life — addressed within A&A's CO₂ EOR + Geosequestration (CCS/CCUS) Consulting page
A&A's CCS/CCUS Track Record
Dr. S. M. (Sam) Avasthi, P.E., Chairman and CEO of A&A, has been working on CO₂ projects since the 1970s, and has worked on some of the major CO₂ EOR and CO₂-storage projects in several regions of the United States, as well as around the world. To read more about it, please click here. This depth of hands-on CO₂ experience — spanning CO₂-EOR, dedicated storage in both depleted fields and saline formations, and the well-integrity and regulatory work common to both — means A&A's CCS/CCUS recommendations are grounded in direct project experience across the full range of project types, not just the pathway being proposed.
What A&A Delivers
A CCS/CCUS engagement with the A&A Consulting Team is built around the practical decisions your company needs to make, including, but not limited to:
• A project feasibility/scoping study, covering site screening, CO₂-EOR versus dedicated-storage evaluation, and storage-setting selection (depleted field vs. deep saline formation)
• Site characterization and storage-performance modeling built to the level of rigor your project's storage setting requires
• A well-by-well life-cycle integrity assessment against Class II and/or Class VI requirements, and workover or new-well program recommendations
• Pilot-test or field-wide project design, evaluation, and optimization
• An MRV plan ready for regulatory submission, and ongoing project surveillance
• Regulatory permitting support, including federal 45Q tax-credit qualification documentation, and high-quality final reports and executive presentations
Related A&A Service: If your company's CO₂ originates from an industrial or power-generation source — cement, iron & steel, power generation, ethanol, bioenergy (BECCS), or direct air capture (DAC) — please see A&A's Industrial CO₂ Storage and 45Q Tax Credit Consulting page.
Related A&A Service: For A&A's site characterization, cavern/reservoir engineering, and well-design services for natural gas, hydrogen, and compressed-air storage in the same depleted-reservoir, saline-aquifer, and salt-cavern settings used for CO₂ storage, please see A&A's Underground (Subsurface) Gas Storage Consulting page.
Frequently Asked Questions
What is the difference between CCS and CCUS?
CCS (Carbon Capture and Storage) refers to capturing CO₂ and storing it underground with no intermediate use. CCUS (Carbon Capture, Utilization, and Storage) is the broader term, which also includes utilization pathways — most notably CO₂-EOR, where the injected CO₂ both recovers additional oil and is permanently stored.
Should our project start with CO₂-EOR or dedicated storage?
It depends on whether the target reservoir can still support economic oil recovery. Many mature and depleting oil and gas fields can support CO₂-EOR, which combines a revenue-generating recovery project with permanent CO₂ storage, and some later add a dedicated-storage phase once EOR operations conclude. A reservoir or formation not suited to EOR — most often a deep saline formation, and sometimes a fully depleted field — goes directly to a dedicated-storage evaluation. A&A's CO₂ EOR + Geosequestration (CCS/CCUS) Consulting page covers this decision in full.
How do we decide between a depleted oil and gas field and a deep saline formation for CO₂ storage?
A depleted or depleting field offers a proven trap and extensive pre-existing subsurface data, generally lowering site-characterization cost and uncertainty, but requires careful legacy well-integrity evaluation. A deep saline formation generally offers far greater storage capacity and wider geographic availability, but starts from a less mature subsurface base and requires independent analysis of its trapping mechanisms, since it has no prior hydrocarbon accumulation to draw confidence from. A&A's two dedicated storage-setting pages cover each in depth, and A&A's consultants can help evaluate which setting — or combination of settings — fits your project.
Do our wells need to be Class II or Class VI?
Class II is the well classification required for CO₂-EOR service; Class VI is required for dedicated CO₂ storage (geologic sequestration), with considerably more stringent construction and monitoring requirements. If your project may pursue dedicated storage in the same field later, it is worth evaluating candidate wells against both standards from the outset, since wells qualified only to Class II standards will not automatically qualify for Class VI service. A&A's CO₂ Injection Wells: Class II vs. Class VI Wells page covers the distinction in full.
Does A&A sell CO₂, injection equipment, monitoring technology, or carbon credits?
No. A&A is an independent consulting firm and does not sell CO₂, injection equipment, monitoring technology, or carbon-credit/offset products, so A&A's CCS/CCUS recommendations are never influenced by a stake in any particular vendor, technology, or carbon-market program.
If you need consulting support on your company's challenging CCS/CCUS projects — CO₂ enhanced oil recovery, dedicated geologic CO₂ storage, well-integrity and regulatory support, or monitoring, reporting, and verification, around the world — please contact us.
