An official website of the United States government.

News Releases from Region 07

EPA Modifies SunEdison Semiconductor Facility Boundaries, Groundwater Monitoring at St. Peters, Mo., Facility

Contact Information: 
David W. Bryan, APR (

Environmental News


EPA seal(Lenexa, Kan., April 25, 2017) - The U.S. Environmental Protection Agency and SunEdison Semiconductor have agreed to a modification of groundwater monitoring requirements and a change of facility boundaries, as part of an Administrative Order on Consent for the SunEdison Semiconductor, LLC, facility, located in St. Peters, Mo.

The modification includes releasing a parcel of about 20 acres from the authority of the Order and terminating the requirement of sampling on that property. The modification also requires SunEdison Semiconductor to properly abandon wells on the parcel being released.

SunEdison Semiconductor operates a facility that produces silicon wafers. Its predecessor, MEMC Electronic Materials, Inc., entered into an Administrative Order on Consent with EPA in July 1996 to remediate and protect groundwater at the facility.

SunEdison Semiconductor will continue to perform groundwater remediation and protection on the remaining property included in the Order. The modification also includes an already-completed requirement for an Environmental Covenant restricting the use of groundwater on the released property.

EPA, in coordination with the Missouri Department of Natural Resources, determined that this modification meets federal and state regulatory requirements and is protective of human health and the environment.

Persons requesting more information about the modification to the Order can contact:

Mike Dandurand
U.S. Environmental Protection Agency, Region 7
Waste Remediation and Permitting Branch
Air and Waste Management Division
11201 Renner Blvd.
Lenexa, KS 66219

He may also be contacted by phone at 913-551-7504, toll-free at 800-223-0425, or via email at

# # #

Learn more about EPA Region 7

View all Region 7 news releases

Connect with EPA Region 7 on Facebook:

Follow us on Twitter: @EPARegion7