Coterra conducts annual benchmarking of the company’s atmospheric emission performance to identify opportunities and challenges relating to various emission sources. At the federal level, greenhouse gases (GHGs) are regulated under two programs: Title 40, Part 98, Subpart W of the Code of Federal Regulations (CFR), “Mandatory Greenhouse Gas Reporting,” which mandates annual reporting of GHGs for subject facilities, and 40 CFR Part 60 Subpart OOOOa, “Standards of Performance for Crude Oil and Natural Gas Facilities,” which imposes emission standards, operation standards and control requirements, as well as recordkeeping and reporting requirements for operations resulting in the emissions of both GHGs and volatile organic compounds (VOCs). While Subpart OOOOa regulates how Coterra conducts our operations to reduce emissions and impacts on the ambient air, Subpart W mandates specific procedures for data gathering, integrity review and calculation methodology for annual reporting. In addition to these federal programs1, Coterra also implements internal processes and procedures to ensure our performance meets or exceeds requirements at all federal, state, and local regulatory levels.
Coterra’s commitment to operational excellence leads to the development of internal guidelines, processes and practices that comply with or exceed regulatory requirements. Coterra performs annual benchmarking of GHG emissions to identify opportunities for emission reduction. For oil and natural gas producers such as Coterra, the two key GHGs that make up the majority of our total emissions are carbon dioxide (CO2) and methane (CH4). The EPA and industry measure the impacts of GHGs in units of CO2 equivalents (CO2e), which is based on converting methane, nitrous oxides and fluorinated gases to CO2 using global warming potential factors (GWP)2.
The primary contributors to methane emissions are from the estimated methane venting during the pre-separation drill-out process of completion operations and natural gas venting associated with liquid unloading the operating of natural gas pneumatic bleed devices to control surface equipment, as well as the venting associated with liquids unloading. The primary contributor of carbon dioxide emissions is from combustion, such as the combustion of natural gas and diesel fuel to operate compressor stations, drilling rigs, generators and completions equipment. The comprehensive ongoing analysis of our emission profile enables us to track CO2 and CH4 emissions by each categorical source to identify equipment and/or emission sources with the most potential for emission reduction. Further, for Marcellus operations, within 180 days of plug drillout following well stimulation, all producing well sites are evaluated for compliance with state mandated emission criteria to demonstrate that they do not exceed exempt thresholds and thereby do not require an individual air permit for significant sources.
In our efforts to identify and minimize CH4 emissions, Coterra evaluates industry proven technologies and seeks to implement best management practices. The four categorical sources of methane emissions are:
Estimated methane venting during the pre-separation drill-out process of completion events
Pneumatic bleed devices
Fugitive emissions from components in service of natural gas such as valves, flanges, etc.
Leak Detection and Repair
Reducing Carbon Dioxide Emissions
Emission Reduction Programs and Achievements