IMPLEMENTING MANUAL LIQUID UNLOADING PRACTICES
Seneca Resources Company, LLC (Seneca), the upstream segment of National Fuel Gas Company (NFG), explores for and produces natural gas wells in the Appalachian Basin in Pennsylvania. Seneca has taken a proactive approach to emissions management, including setting a methane intensity reduction target, which can be explored further in our Corporate Responsibility Report available on National Fuel Gas Company’s website. Since joining The Environmental Partnership (TEP) in 2018, Seneca has committed to:
• Implementing best practices to minimize emissions associated with removal of liquids that can build up and restrict gas flow as wells age;
• Conducting Leak Detection and Repair (LDAR) surveys, and promptly repairing on all active assets; and
• Replacing, removing, or retrofiting high-bleed pneumatic controllers.
Recognizing the need to manage liquid unloading events, which can be a significant source of emissions as wells age, Seneca began tracking these events and implemented manual unloading practices for well management as a best practice recommended by TEP. The Seneca team also installed plunger lubricators as part of its wellhead design on new wells, allowing for minimized downtime and expedited plunger deployment when necessary. Seneca continues to look for ways to optimize and improve strategies, technologies, and techniques for managing and mitigating well liquid unloading emissions. After trialing different technologies and operational best practices, Seneca’s current strategy to mitigate manual well unloading events to atmosphere includes implementing well pressure builds (i.e., shut-in periods to allow for pressure increase), using capillary strings, installing plungers, and deploying mobile unloading compressors. These efforts have led to an 84% decrease in vented emissions from liquids unloading compared to our 2020 baseline. The Seneca team remains focused on identifying additional opportunities and design changes to further reduce and prevent emissions in this category.