So – You Failed a RATA, Now What?

What’s a RATA?

A RATA is a Relative Accuracy Test Audit, and it’s typically performed as an annual audit on a continuous emissions monitoring system (CEMS). A third party brings an independently certified CEMS and hooks it up to your stack, and then you collect data at the same time and compare results between CEMS.  They need to be within a certain threshold – a relative accuracy (RA) – to pass.  If you don’t pass, then your CEMS is “out of control” and not gathering valid data from the hour that the RATA failed until the hour that you successfully pass a RATA.

You’ve scheduled your RATA, but it’s not going well.

The stack testers have mobilized and spent time setting up their equipment on the stack. They’ve spent hours collecting data, and it’s looking grim. Your relative accuracy has been outside the bounds of where it needs to be for a few runs, and It’s looking like your RATA is going to fail.  It’s getting dark and late, troubleshooting efforts aren’t going well, and the stack testers can’t continue. What do you do?

Should I abort my RATA?

Well – maybe, but probably not. You may be considering aborting the RATA to avert a failure, but depending on your applicable Federal and State Regulations, aborting a RATA might not actually spare you from your data being considered out-of-control. 40 CFR Part 75, for example, considers an aborted RATA as if it were failed. If you have reasonable confidence that the system will get within the acceptable relative accuracy in more runs, then it makes sense to keep going. If not – well, then it might be time to abort and look to the next steps. Aborting a RATA can be seen as evasive by environmental agencies, especially if there are not explicit rules regarding how to handle an aborted RATA. Most states have guidance around the issue, and generally, if the data is suspect enough to consider aborting the RATA, then the data collected during the RATA should be invalidated and investigated. While not all applicable regulations address how data are to be handled during these times, most states require invalidation of tests results. The next sections will assume that the RATA failed, or it was aborted and your CEMS is now considered to be out-of-control.

So, I failed my RATA. What now?

The first thing you should do is notify your respective administrator or agency. If someone from the agency is on site observing, it’s still a good idea to send notification from the facility itself. Investigate the issue, schedule corrective maintenance, and reschedule your RATA. It is important to have a plan of action. Once you have a plan, it can be helpful to call your regulator, let them know the situation, and ask for guidance if you feel it’s necessary. A regulator is much more likely to work with you and your facility if they are informed and involved.

Next, consider your timeline. Do you know what caused the system to have issues? Do you know how long it will take to complete troubleshooting?

Most facilities that have CEMS that require a RATA have data availability requirements. Downtime from a RATA will quickly eat into your data availability if it’s not resolved quickly, and there are a lot of things that could prevent a successful RATA from being completed quickly – lead time on parts, stack tester availability, complex troubleshooting. If the system will be down for an extended period, consider the following:

How will the downtime affect my data availability?

Be aware of how much the out-of-control status will affect your data availability. Often, insufficient data availability can result in a notice of violation and/or fines from the agency. Understand your data availability thresholds, where your availability stands as of right now, and worst-case data availability based on your tentative timeline.

Do I have another way of getting indicator data?

Indicator data is data that isn’t gathered by a certified continuous monitoring system. Indicator data cannot be used to report compliance averages, but it can be used to show general stack conditions while the system is out-of-control. For example, if your facility is required to monitor NO_X emissions and the monitor failed its RATA, process monitors or temporary replacements could potentially be used to collect data. If the intent is to convert a temporary CEMS into a permanent replacement, initial certification will have to be completed, which also ends with a RATA.

How well are we documenting our troubleshooting efforts?

For any event that might result in significant downtime – and a failed RATA is certainly one such event– it’s important to document every troubleshooting step that was taken to try to resolve the issue. In the event of a regulatory inquiry, having complete records can help paint a favorable picture for your facility.

Is my DAHS reflecting the situation correctly?

Most DAHS programs won’t invalidate data automatically following a failed RATA and sometimes may not even automatically recognize and flag a RATA. It is up to the facility’s personnel to identify the data that is affected by the failed RATA and invalidate appropriate time periods accordingly. We recommended you closely monitor the RATA results until the RATA is passed to ensure the data is flagged appropriately, as it will help show data availability correctly.

Conclusion

Understanding how to respond to monitoring issues can be overwhelming. Getting administrative tasks completed while your team is trying to troubleshoot, on top of all the other environmental health and safety tasks that need to be completed at the same time, can be difficult. If you have questions or would like guidance for navigating your RATA issues, please reach out to me at tcunningham@all4inc.com or 610-422-1106. ALL4 is here to answer your questions and assist your facility with any aspect of environmental regulatory compliance and our team of monitoring experts is ready to help you understand CEMS requirements.