Environmental Data Management: Simple Strategies for Missing Emissions Data

Handling last-minute data gaps in emissions reporting and environmental data management

A healthy environmental data management system requires accurate greenhouse gas (GHG) emissions data and is crucial for organizations aiming to meet environmental regulations, achieve sustainability targets, and build trust with stakeholders. Reliable data allows for informed decision-making, reduces risks of non-compliance, and contributes to a transparent environmental footprint. However, even with the best efforts, data gaps can occur—whether due to technical limitations, complex reporting requirements, or human error. Recognizing that missing emissions data is a common challenge, this blog provides practical strategies to help you identify, manage, and mitigate these gaps effectively. Read on to explore simple yet effective methods for enhancing your emissions data reporting and maintaining compliance.

Missing emissions data

If you are missing a piece of data for the year, don’t panic. The important thing is to identify these missing data points as soon as possible so you can select the best strategy for managing the situation.

Assess alternative calculation methods

First, review the different calculation methodologies for a given source. Required data is calculation-method specific, so if you are missing one piece of information, it is often possible to check an alternate method against the data you have available. For instance, there are 4 methods of calculating GHG emissions for amine units under 40 CFR 98, Subpart W:

• Method 1: CEMS 
• Method 2: Volume and CO2 composition in vent/stack gas 
• Method 3: CO2 composition in plant inlet and plant residue gas and amine throughput volume 
• Method 4: Simulation software

If a processing facility did not collect any source-specific data for a particular amine unit at a processing location, you may still be able to utilize the following data already reported for the facility to perform calculation method 3. 

• You may assume that the amine unit throughput is equivalent to the total volume of gas entering the facility. If there is more than one amine unit, then the total throughput can be evenly split under each amine unit. 
• You may assume that the amine unit inlet gas composition is equivalent to the inlet gas composition measured for the facility. 
• You may assume that the amine unit outlet gas composition is equivalent to the residue gas composition measured for the facility. 

Using an alternative calculation methodology is an acceptable practice that provides accurate emission results and does not require disclosure of missing data procedures. 

Employ missing data procedures

If there are still data gaps after assessing alternative calculation methods, EPA procedures specify practices that ensure reports maintain high accuracy and reliability, even when data points are missing. These procedures include:  

1. Standards set by the rule, such as using an emission factor,
2. The average of other measurements,  
3. Best engineering estimates, or  
4. A value that was used in the previous year. 

The EPA’s Greenhouse Gas Reporting Program sets forth specific guidelines for calculating and reporting emissions from the oil and gas sector. When the program began, it allowed facilities and suppliers to use the Best Available Monitoring Method (BAMM) to estimate emissions from specific sources in cases where it was challenging for a facility to acquire, install, and operate all of the required monitoring equipment by the required date. This temporary allowance enabled facilities to continue reporting while gradually acquiring the necessary equipment. 

This changed in 2017, however, and BAMM is no longer an accepted method. Instead, facilities must follow strict missing data procedures to account for any gaps in measurements. Under the Subpart W, these procedures require you to document specific information within the Subpart W Spreadsheet, including: 

• What piece of data was estimated? 
• At what frequency is the data usually measured?  
• How many times were measurements missed?  
• What procedure was used to estimate the missing data? 

Verify recordkeeping procedures

Beyond resolving instances of missing data, it is critical to ensure your data is being properly recorded. Operations are required to maintain records on-site that document how the data provided in their annual GHG reports were developed. These records include a monitoring plan describing where and when samples were collected, methods used to analyze samples, and the procedures used for quality assurance and quality control.

Verifying data is collected and maintained as required (for example, records must be kept for at least 3 years following the respective reporting period in a format that is readily available for inspection and review) improves the quality of your reports and will help prevent future data gaps.

Environmental consulting services to streamline your emission reporting 

Partnering with Montrose can greatly simplify and enhance your emissions reporting process. Our EH&S Management Information Solutions provide companies with strategy, selection, setup, and support in implementing robust data management tools, ensuring accurate tracking, integration, and reporting of critical emissions data. With comprehensive support for identifying and filling data gaps, automated tracking features, and user-friendly dashboards, we help you stay on top of complex compliance requirements while reducing the risk of missed information. Trust Montrose to streamline your emissions data management and empower your team with insights for better decision-making and transparent reporting.