Ethylene oxide: Technical Reviews and Outreach to Potentially Affected Communities

Status Report — Evonik Corporation, Milton, Wisconsin.

As EPA pursues its mission to protect public health and the environment, addressing ethylene
oxide (EtO) remains a major priority for the Agency. EPA's National Air Toxics
Assessment (NATA), released in August 2018, identified a number of areas (census tracts) with
potentially elevated risk from continuous exposure, over 70 years, to EtO in the outdoor air.
NATA estimated these risks based on EtO emissions from 2014, which were the most recently
available at the time.

NATA is a screening-level analysis that is intended to identify pollutants or areas for closer
examination. Because of this, additional work is needed to better understand emissions in
areas that NATA identified as potentially having elevated risk. EPA has been supporting its state
air agency partners as they conduct that work and identify opportunities for reducing EtO
emissions from individual facilities, while the Agency reviews its national regulations for
industrial facilities that emit EtO. Actual risks today may be higher or lower than NATA
estimated due to several factors, including updated or more refined facility emissions
information, or recent facility changes such as the installation of pollution controls.

The information below describes the technical analyses conducted for Evonik Corporation,
located in Milton, Wise., as part of the follow-up work conducted since NATA was issued in
August 2018. It also summarizes outreach to nearby communities about the NATA results. EPA
is providing this information, in part, in response to the EPA Office of Inspector General's March
31, 2020, Management Alert which called on EPA to provide information to the 25 communities
that NATA identified as potentially having the highest risk from EtO emissions.

Technical reviews conducted

Evonik Corporation, located in Milton, Wise., is a chemical manufacturing plant. It makes
specialty chemicals that are used in household, industrial and institutional cleaners, as well as
mining, roof coatings, asphalt and other industrial applications.

•	Emission reductions: The Wisconsin Department of Natural Resources (WDNR) has been
working with Evonik and the previous owner since 2010 to reduce emissions. From
2014 to 2019, reported emissions dropped 85% from 792.4 to 111.45 pounds per year.
This reduction is the result of emissions verification, removal of equipment, and
installation of emission-reducing components.

•	Compliance Inspection: On June 25-26, 2019, WDNR and EPA conducted a joint
inspection of the facility, which included leak detection using Method 21. The purpose
of the inspection was to ensure compliance with the Clean Air Act. WDNR did not find
violations.


-------
Outreach conducted:

• Website: On June 17, 2020, WDNR created a website about Evonik. The website gives
background on the facility, including its reported EtO emissions since 2012.

2


-------