Abandoned Wells: Not Dead Yet

California recently completed plugging operations for two oil previously plugged wells at Summerland Beach at an estimated cost of $900,000. The wells were part of an eight well re-abandonment effort in Santa Barbara County by the California State Lands Commission and its subcontractors.

The California coastline may have over 200 legacy wells, relics of oil and gas operations of the late 1800s and early 1900s. These vestiges of early oil production in California have no known owners and predate any regulatory oversight, recordkeeping, and plugging standards.

Plugging Problem: Expensive & Extensive

According to Geologic Energy Management (CalGEM), costs for plug and abandonment can vary drastically, ranging from $25,000 to +$1,000,000 per well, depending on location, depth, technical expertise, and equipment needed to decommission the well.

California’s oil production began in the late 1800s. CalGEM maintains well records from the early 1900s, and is responsible for nearly a quarter million wells, with over 37,000 listed as idle (nonproductive, owners identified). There are also some 17,000 wells idle for 15+ years, and over 5,000 listed as orphaned (operator insolvent) or deserted/potentially deserted (no operator found/not operational/not in financial or legal compliance).

Some 66% of unplugged California wells may be emitting methane, says a 2020 study. As these wells age, cement fails and other downhole barriers degrade, requiring more intensive remediation.

​Funding for state P&A:

• Oil, Gas, and Geothermal Administrative Fund (OGGA) – operator assessment fees, expenditure capped $5 million/year
• Hazardous and Idle-Deserted Well Abatement Fund (HIDWAF) – operator idle well fees for hazardous well P&A
• California State General Fund – $100 million FY 2023 & FY2024 for orphan/deserted well P&A
• Initial August 2022 federal grant funding – $25 million, $140 million potential future grants

Doing More with Less: New Technology Changing the Game

​​​​​​​​Previously abandoned wells with compromised barriers in the wellbore and/or annulus are typically dealt with via re-entry, an expensive solution requiring a rig to drill out existing barriers and facilitate replacement which may require multiple attempts. With so many wells to plug, finding efficient and economical solutions is paramount.

The latest innovation in biomineralization technology, NanoSeal™, enables existing barriers to be restored instead of replaced. NanoSeal™ is the only sealant capable of accessing sub-micron leaks and is capable of penetrating over 1,000 ft into compromised barriers. Utilizing a Deep Penetrating Annular Surface (DPAS™) BioSqueeze® to inject NanoSeal™ riglessly into previously plugged wells with gas/fluid flow provides a more effective solution than standard re-entry at a fraction of the cost.