WVDEP implements new requirements through collaborative agreement with Union Carbide related to Ethylene Oxide


CHARLESTON, W.Va. – The West Virginia Department of Environmental Protection’s (WVDEP) Division of Air Quality (DAQ) has signed a collaborative agreement with Union Carbide Corporation’s Institute facility to implement additional measures that will reduce ethylene oxide (EtO) emissions.

The agreement, available on the WVDEP’s EtO webpage, is specific to UCC’s EtO distribution system at its Institute facility, which unloads rail cars containing EtO and supplies it to consumers at the Institute and South Charleston chemical facilities.

While this facility is currently in compliance with all of the EtO-related terms and conditions of its air permits, these new requirements go above and beyond state and federal rules and regulations. They will be enforced at the state level and reduce the amount of EtO emitted and the potential risk in the Institute area.

UCC’s EtO distribution facility will be required to:

  • Significantly reduce its allowable emission limits for EtO;
  • Identify and fix leaks at levels 50 to 1,000 times lower that what is required by current regulations;
  • Develop a site-specific screening program for rail cars containing EtO in its service;
  • Continue working with WVDEP and the U.S. Environmental Protection Agency (EPA) to develop improved monitoring for EtO emissions.
“This agreement is an important step in ensuring that the health and well-being of West Virginia’s communities remain protected,” said WVDEP Secretary Harold Ward. “It is the result of working through our regulatory process, collecting fence line monitoring data, and conducting significant public outreach.”

The WVDEP conducted a short-term EtO air monitoring project in 2022, which sampled seven sites in and around the chemical facilities in Institute and South Charleston over four 24-hour periods.

The agency’s final report on the project is also available on the WVDEP’s EtO webpage. A public meeting on the final report is set for Thursday, March 2, 2023 from 6 to 8 p.m. at the Wilson Union Hall on the campus of West Virginia State University in Institute (301 Washington Ave. Dunbar, WV 25064).


The (EPA) conducted a study of air toxic emissions across the United States using data from 2014. That data was compiled and released by the EPA in 2018 in a report called the National Air Toxics Assessment (NATA). The NATA was a broad overview of air emissions across the country – commonly referred to as a screening tool – and is designed to identify areas that may need further investigation.

While the assessment was being conducted, the EPA reevaluated EtO and reclassified it from a probable human carcinogen to a known human carcinogen, while also increasing its toxicity value.

The 2018 assessment, based on 2014 data, identified four census tracts in West Virginia, all of which are nearby EtO-emitting facilities in Institute and South Charleston.

The potentially elevated risk is not due to new emission sources or increased emissions from permit holders, but rather to the EPA's finding that long-term exposure to EtO may be more harmful than previously thought.

This potential risk is based on assuming continuous exposure to elevated levels of EtO for 24 hours per day, seven (7) days per week, over 70 years.

The WVDEP has collected updated and site-specific emissions data, conducted short-term air monitoring, performed more accurate emissions modeling, and engaged with the public through multiple in-person and virtual meetings.    

Since the release of the 2018 report, the EPA has replaced the NATA with a new screening tool - AirToxScreen. This assessment estimates air toxics using emissions data from the most recent year of complete data available.

From 2014 to 2021, the reported EtO emissions from the Institute site have decreased by over 50 percent and emissions from the South Charleston site have decreased by over 80 percent.

The West Virginia Department of Health and Human Resources, Bureau for Public Health, mapped all cases of the types of cancers potentially related to EtO in Kanawha County from 1993 through 2019. Areas with the highest rates of these cancers do not cluster around the facilities identified by the EPA, nor does Kanawha County have higher rates of these cancers compared to the rest of West Virginia. 

The WVDEP is committed to staying engaged nationally as the EPA works to update regulations to reduce impacts from hazardous air pollutant emissions like EtO. The WVDEP is continuing to work with West Virginia facilities and communities to reduce the potential health risks associated with air toxic emissions.

For more WVDEP news and information, go to https://dep.wv.gov. ​Also, connect with the agency on all social media platforms. Follow @DEPWV on Twitter, Like us on Facebook at https://facebook.com/depwv/, and find us on YouTube at Environment Matters​.


Terry Fletcher
304-926-0499 ext. 49720