Everything You Should Know About Federal Methane Measurement Guidelines for MCWs

These guidelines set the federal standard for properly measuring methane emissions from Marginal Conventional Wells (MCWs) and dictate how proper measurement should be conducted for federal funding eligibility under the Inflation Reduction Act’s (IRA): Mitigating Emissions from Marginal Conventional Well (DE-FOA-0003109) — along with likely subsequent federal mandates and methane emission programs to be funded and conducted in the future.

Understanding Methane Measurement Guidelines for MCW

This is what grant recipients should know about the methane measurement guidelines for MCWs, including why they are being implemented, how they may affect your operations, and how you can comply with them.

Why were these guidelines created?

In December of 2023, as part of President Biden’s Investing in America agenda, the US Department of Energy and Environmental Protection Agency announced a partnership to fund Funding Opportunity Announcement DE-FOA-0003109. This funding opportunity distributes a total of $350 million in formula grant funding to 14 states.

The guidelines created for DE-FOA-0003109 are specific to MCWs. The announcement defines MCWs as “idle or producing onshore vertical or slightly deviated oil or natural gas wells (excluding highly deviated or horizontal wells) with a known owner/operator producing less than or equal to 15 barrels of oil equivalent per day (BOED) and/or 90 thousand cubic feet (Mcf) gas per day over the prior 12-month +period.”

MCWs are being targeted for environmental remediation because they contribute an outsized amount of methane emissions (an estimated 60% of US natural gas production emissions and 40% of US oil production emissions), despite only contributing 6.2% of oil and 5.8% of natural gas production. There is also significant evidence that loss rates from MCW sites increase as production declines, resulting in disproportionally high emissions from ultra-low producing wells. 

DE-FOA-0003109 is federal funding to be awarded to various States to assist well owners and operators  who voluntarily choose to permanently plug and abandon MCWs in their operations. By doing so, the Federal government hopes to accomplish the following goals:

• Mitigate, to the maximum extent possible, methane and other GHG emissions by assisting the states and owner/operators to voluntarily identify and permanently plug MCWs.
• Measure methane emissions to provide a preliminary screening of emissions from MCW sites as a mechanism to inform plugging prioritization.
• Measure methane emissions from MCW sites prior to and following the plugging and abandonment to quantify mitigated emissions.
• Support elements of environmental restoration required for full compliance with applicable state or federal well plugging and abandonment standards and regulations.

In order to be awarded State funding for these purposes, grant recipients must follow specific federal guidelines for the process of measuring methane emissions and plugging their MCWs. These are the guidelines released by the Department of Energy’s National Energy Technology Laboratory on June 14, 2024.

By following these guidelines, owners and operators who volunteer to permanently plug and abandon their MCWs can verify that they have adequately measured and monitored methane emissions prior to and following plugging to confirm that these plugged wells are no longer emitting methane. 

How do I need to measure methane emissions from MCWs according to these guidelines?

Grantees are required to measure methane emission rates both prior to and following their plugging and abandonment of MCWs, using one of the approaches specified in the guidelines.

You can choose any of the following techniques for measuring methane emissions before and after plugging that meet the method detection limit of 100 gram/hr (g/hr) required for MCWs. Which method will be right for your MCWs depends on a wide variety of factors including desired performance metrics and MCW site characteristics.

The techniques for methane measurement pre-approved by the guidelines fall into three categories:

Direct source emissions measurements

These approaches require personnel to sample directly from potential emission locations using portable analytical systems.

These are the most high-risk approaches to personnel on-site and should be conducted with by trained environmental professionals; however, these methods have been proven to provide the most accurate emission rate measurements. Direct source emission procedures include:

• High flow sampling, in which tests introduce a focused vacuum at high flow rate to potential leak points, completely capturing the leakage and analyzing its methane concentration.
• Flux chamber sampling, which uses sealed containers with a fixed volume that are placed over an identified leak in the MCWs. From there, the emission rate and concentration of methane within the container is measured over time by analyzing air samples from within the flux chamber at different points of time.
• Bag sampling — emission rate measurement, which is an alternative but similar approach to the rigid flux chamber method that uses flexible anti-static Mylar bags of various sizes to custom-fit a containment around a potential leak source.
• Bag sampling — flow rate measurement, which is used for the measurement of leak flow rate only. This technique involves placing anti-static bags of a known volume directly over a leak and recording the time it takes for the bag to be filled.
• Methods that combine methane concentration measurements with flow rate measurements, which involve calculating emission rate by combining data collected from two different instruments – one used to measure flow rate with the other measuring gas concentration.

Near-field measurements

Near-field measurement techniques involve placing analytical instruments a few meters from the well site. These instruments can collect data if they are either placed downwind from the well site or if they are capable of mobility via a surveying platform.

Near-field measurements are considerably less hazardous than direct source measurements because they don’t require personnel to be as close to the well, but plume dispersion can introduce uncertainty in the methane emission rate estimation. Near-field measurement techniques include:

• Ground-based/stationary surveys coupled with Gaussian plume dispersion modeling makes estimations of methane emission rates from point sources using downwind measurements of methane concentrations.
• Drone-based surveys are a strong alternative when accessibility is an issue. Drones can be equipped with methane sensors that work based on multiple principles. Combining the concentration measures derived from drone sensors with wind sensor measurements, either also on the drone or on the ground, can be used in plume dispersion modeling to estimate methane emissions.

Remote sensing

Though there are not currently aircraft or satellite-based methane sensors that meet the 100 g/h requirement for MCW methane measurement, this technology is rapidly evolving. If these technologies could be proven to meet the detection limit in the future, they could be reviewed by NETL and used to measure MCWs while complying with these guidelines.

Additional prerequisites for applicable approaches

No matter which approach grantees take to measuring methane emissions, they must also comply with the following guideline standards to be eligible for funding assistance:

MCW plugging requirements: Plugging and abandonment procedures must follow all applicable state or federal requirements.

GGRP quantification (when applicable): Facilities that report to the Greenhouse Gas Reporting Program are required to follow Subpart W quantification methodology to quantify the methane mitigated from plugging.

On-site reporting specialist: A measurement specialist must be at the site prior and subsequent to plugging and remediating a well. This specialist must:

• Have completed all required safety training (e.g., H2S, OSHA40/HAZWOPER) necessary to gain access to a site.
• Have completed a minimum of 20 hours of training specific to the equipment and methods described in the guidelines.
• Be familiar with reference documents in guidelines.
• Be able to recognize and avoid/mitigate safety hazards related to the oil and gas well field conditions.
• Be aware of and evaluate all potential leak, flare, and vent points at an MCW site.
• Be prepared to submit data and results in a format that can be easily incorporated into the relevant agency database tool

Submission of proposal to NETL: The specific measurement equipment and methodology proposed by the contractor or qualified measurement specialist conducting the measurement and plugging operation must be submitted for review by the NETL Federal Project Manager in advance of the field campaign in accordance with guidance within the Statement Project Objectives.

This proposal must contain the following information:

• Weather/environmental conditions
• MDLs for emission measurements that result in a non-detect classification must be no more than 100 g/h with a 90% probability of detection.
• A planned quality assurance/quality control program where the contractor or specialist makes a second set of measurements at ~5% of randomly chosen wells to verify the precision of the selected methodology. These repeat measurements must be conducted on the same day.

Data reporting: Award recipients will develop and maintain public websites that will include the following information:

• Wellhead location and American Petroleum Institute number of all MCWs.
• Estimated annual reduction of methane emissions from each plugged well.
• Total estimated annual reduction of methane emissions from all plugged wells.

These websites must be updated once per month.

If you’re interested in plugging MCWs, Antea Group can help you comply with these guidelines. Get in touch with our expert to learn more.

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