Context Corner Edition 2 – BTEX
Providing relatable context regarding Volatile Organic Compounds as part of CNX’s environmental monitoring and disclosure concept "Radical Transparency."
December 20, 2023
By Carrie Crumpton, CNX Vice President of Environmental Strategy
I hope you’ve had a chance to review the newest information available on our Radical Transparency website, the addition of monitoring results for a group of volatile organic compounds (VOCs), collectively known as BTEX (benzene, toluene, ethylbenzene, and xylene) for our NV110 pad. Moving forward, you’ll find BTEX results on pages 5 and 6 of the site monitoring details as data become available for each location that we are monitoring. I have received a few questions on this new information that I’d like to answer for you – keep the questions coming!
Hey Carrie, what is BTEX and why measure?
BTEX is an acronym for a group of VOCs that are often found together as a natural component of crude oil, gasoline, diesel fuel, and heating oil. Some of these compounds are also used extensively in various manufacturing processes, including the production of synthetic materials, fuel additives, and consumer products, but can also be found in sea water, emissions from volcanoes, and forest fire smoke. In addition to these industrial and natural sources, some studies suggest that cigarette smoke accounts for nearly 50% of the country’s passive exposure to benzene.
So, why measure? Because prolonged exposure to high concentrations of BTEX can lead to mild to severe health effects. That is why CNX is measuring and comparing to the Inhalation Minimum Risk Level (MRL), which is an estimated level of daily human exposure that is not expected to result in adverse effects to human health.
BTEX is a straightforward and useful suite of compounds to monitor because it provides a well-rounded picture of all potential VOCs in an area by using the 4 measured components as indicators. And that’s the approach we are taking with our realtime monitoring effort.
The BTEX suite is useful for assessing the potential impact of industry in an area. Monitoring BTEX will allow quantification of these compounds, demonstrate compliance with local regulations, and even help identify if there are leaks in storage or processing infrastructure.
Hey Carrie, how is BTEX measured?
To measure potential concentrations of BTEX, CNX is utilizing EPA Reference Method 325. This method describes the passive sampling procedure for collecting and analyzing air samples that are collected onto sorbent tubes. This sampling approach exposes the tubes, which are located at four sampling stations surrounding the pad, to the air for 14-day periods. At the end of the 14-day period, the tubes are collected and sent to a qualified laboratory where the material inside is analyzed using gas chromatography to detect the concentration of BTEX. The sample results provide us with an average concentration in the air for the 14-day exposure period for each sampling station. The results from those 14-day samples are presented on our website charts where the results are compared to the (MRL) I mention above.
You’ll note BTEX results you may see on these charts are often lower than the detection limit of the compound (which is the lowest quantity of a substance that can be distinguished from the absence of the substance in a laboratory setting).
Continue to check back in as we add new data and locations to our Radical Transparency Monitoring Sites and enhance the interactive viewing experience.
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