EPA Issues Regulations for Oil and Natural Gas Sector Tank Emissions

On March 8, 2024, the United States Environmental Protection Agency (EPA) promulgated Standards of Performance for New, Reconstructed and Modified Sources and Emissions Guidelines for Existing Sources: Oil and Natural Gas Sector Climate Review (40 CFR 60 subparts OOOO, OOOOa, OOOOb and OOOOc, often referred to as “Quad O”). Tanks with the Potential to Emit (PTE) greater than 20 tons/year of methane are now required to capture and reduce emissions by at least 95%. This is directly applicable to affected facilities that began construction, reconstruction, or modification after December 6, 2022.

Owners and operators have until May 2025 to achieve compliance with the revised tank standards. Closed vent systems must be designed and operated to capture and route all gases, vapors and fumes to a process or a control device. EPA’s goal is to achieve no identifiable emissions. Designs must be certified by an engineer.

Compliance Requirements Focus on Reducing Emissions

Under the final rule, production tanks with a PTE of 6 tons/yr of VOC or 20 tons/yr of methane are now required to capture emissions and route to a process or a control device. In addition to control devices, operators are also required to install hatches that provide an appropriate seal to reduce emissions.

EPA has also clarified the definition of a modification to an oil storage facility. A facility is considered to be modified if any of these conditions are met:

• Adding a storage tank
• Replacing an existing storage tank that results in an increase in capacity
• Receiving additional throughput from production well(s)
• Receiving additional fluids which cumulatively exceeds throughput used in the most recent determination of the facility’s PTE

EPA defines reconstruction to mean the replacement of at least half of the storage vessels in an existing tank facility that consists of more than one storage vessel.
If a tank facility is modified or reconstructed, it is considered an affected facility under 40 CFR 60 OOOOb and requires a combustion system if the PTE is greater than 6 tons/yr of VOC or 20 tons/yr of methane.

Next Steps: TRC Can Help

TRC’s team of engineers can review your process operations and conditions to help you determine the compliance status of your existing equipment. We will model your facility’s operations and provide recommendations to achieve compliance. We have decades of oil and gas engineering experience and the depth of staff to help operators meet the compliance deadline.