How to Choose the Right Alternative Technology for Methane Monitoring

With the introduction of OOOOb and OOOOc, the Environmental Protection Agency (EPA) has established a streamlined process for approving new technologies without undergoing a full rulemaking procedure. Over the last couple of weeks, the EPA approved a handful of alternative technologies, including ChampionX’s Aerial Optical Gas Imaging (AOGI) platform. This marks a significant step forward in enabling the adoption of innovative methane detection methods in place of AVO methods, OGI and Method 21.  

What does it take to get EPA approved as an alternative technology? 

The approval pathway requires applicants to demonstrate the scientific rigor of their methods, ensuring they are both repeatable and auditable. The EPA has defined two primary technology pathways: one for continuous monitoring systems and another for periodic screening processes, paving the way for innovative approaches to methane detection and compliance. 

The approval process requires technology providers to outline the scientific background, the methodological steps and calculations they use to develop their minimum detection level of methane. This MDL needs to be rigorously proven with in-field experiments and trials to demonstrate the operating envelope of the method. The operating envelope is  the range of conditions a method can successfully detect methane at their described minimum detection level with a 90% probability of detection.  

The alternative test method needs to have a method or protocol document that describes how to perform the method in a repeatable fashion. This aids operators, regulators and other interested parties in auditing the method and ensures that they remain in compliance when using the alternative method. 
 

Why use an alternative method? 

With the adoption of OOOOb and OOOOc, the number of regulated facilities under these rules has increased significantly. Previously, OOOOa was the only rule regulating methane and included new or modified sites from September 2015 through December 2022. OOOOb rules only affect sites built after December 2022. However, OOOOc compels states to make equivalent or stricter plans for ALL eligible sites constructed before December 2022.  

Including sites that were previously grandfathered into older regulations has drastically increased the number of sites from around 80,000 to close to 1 million. For the oil and gas industry, this results in increased demand for LDAR programs to monitor the almost tenfold increase in regulated sites, driving up operational costs and work for operators. 

Alternative methods, however, can increase the productivity of LDAR teams. Many methods that have been approved or are in the application process offer oil and gas operators technologies that can cover many more sites than a traditional LDAR team using OGI or Method 21. ChampionX Aerial OGI, for example, can cover over 150 sites daily, whereas a typical OGI technician could cover around 5 sites.  

What should I know about the alternative methods for periodic screening? 
 
Technologies are classified in two different ways. First, the minimum detection level of the technology determines how frequently it must be used to monitor a site. Second, the spatial resolution of the site determines how much area the follow-up inspection needs to cover. 

Detection threshold 

The minimum detection level is the emission rate where the technology will detect 90% of leaks of that size, i.e., the probability of detection. The two tables below show a spectrum of thresholds and how each level has a separate surveying frequency. For some levels, an annual OGI inspection is also included.  These different minimum detection thresholds help operators select the right technologies for their operations. 

Table 1 to Subpart OOOOb of Part 60—Alternative Technology Periodic Screening Frequency at Well Sites, Centralized Production Facilities, and Compressor Stations Subject to AVO Inspections With Quarterly OGI or EPA Method 21 Monitoring 

Table 2 to Subpart OOOOb of Part 60—Alternative Technology Periodic Screening Frequency at Well Sites and Centralized Production Facilities Subject to AVO Inspections and/or Semiannual OGI or EPA Method 21 Monitoring

These thresholds were selected through modeling. The EPA ran mitigation models to determine which thresholds and surveying frequencies were necessary to achieve equivalent mitigation as routine Method 21 and OGI inspections.  

Spatial resolution 

The spatial resolution is the ability of each technology to pinpoint a leak on a site. The EPA created three different levels: 

1. Facility-level – The ability of a technology to identify a leak within the bounds of a facility. Facility-level methods require a follow-up inspection of the whole facility. 

1. Area-level – The ability of a technology to identify a leak within 2 meters of the source. Facility-level methods require a follow-up inspection of each fugitive component and closed vent system with a 4-meter radius of the predicted source. 

1. Component-level. The ability of technology to identify a leak within 0.5 meters of the source. Component-level methods require a follow-up inspection of each fugitive emission component and closed vent system within a 1-meter radius. 

The follow-up inspection must be done using OGI or Method 21 techniques.  

What should I choose as an alternative method? 

Ultimately, it depends on the operations of the company. Some questions that need to be answered are: 

1. How equipped is my team to use this new method? 

1. Do I have the capacity to respond to these leaks in the allotted window? 

1. What frequency will I have to do inspections? 

1. What is the associated cost of doing these inspections? 

Some technologies are better than others, though. The higher the spatial resolution, the less follow-up inspection time there is. Given that follow-up inspection must include all fugitive emission components and the entire close vent system, even if the vent system continues outside of the specified area, the spatial resolution of technology significantly impacts the cost and time needed to complete the appropriate follow-up.  

Why choose AOGI? 

AOGI is fast and efficient. The most significant benefit, however, is that it is built upon tried-and-true OGI camera technology. Given how prevalent OGI technology is in the oil and gas industry, every LDAR team has already worked with OGI videos and has them integrated into their workflows. Unlike other advanced technologies, interpreting the results has no learning curve for an experienced LDAR crew. 

In addition, ChampionX AOGI has a component-level resolution, meaning operators can quickly inspect the location and find the leak. As the AOGI is based on OGI camera technology, operators even get a crystal-clear high-definition video of the leak itself, meaning diagnosis of many leaks can happen before even arriving at the site.  Unlike other technologies, OGI allows operators to know where a leak is, not just in two-dimensional space, but they can also determine how high the leak is off the ground. An overlay of a plume on a map cannot compare to a video of the leak. 

Learn more about ChampionX’s AOGI system: https://www.championx.com/products-and-solutions/emissions-technologies/aerial-optical-gas-imaging/