DAQ-2025-001337

195 North 1950 West • Salt Lake City, UT
Mailing Address: P.O. Box 144820 • Salt Lake City, UT 84114-4820
Telephone [phone] • Fax [phone] • T.D.D. [phone]
www.deq.utah.gov
Printed on 100% recycled paper
State of Utah

Department of
Environmental Quality

Kimberly D. Shelley
Executive Director

DIVISION OF AIR QUALITY
Bryce C. Bird
Director

SPENCER J. COX
Governor

DEIDRE HENDERSON
Lieutenant Governor
DAQC-224-25
Site ID 14178 (B1)

Madeline Fleisher
Owens Corning World Headquarters
One Owens Corning Parkway
Toledo, Ohio 43659

Dear Ms. Fleisher:

Re: No Further Action Letter – RE: Notification of Non-Compliance by Owens Corning
Insulating Systems, LLC Under the Utah Environmental Self-Evaluation Act

On December 28, 2023, the Utah Division of Air Quality (DAQ) received a self-disclosure
notification and request for full enforcement mitigation under the Environmental Self-Evaluation
Act, Utah Code §§ 19-7-101 through 19-7-109 (the Act) for potential non-compliance with
condition I.3 of Approval Order (AO) DAQE-AN141780008-23 for the unapproved installation of
one 800-900 horsepower (hp) diesel-fired emergency generator engine and one 200 hp diesel-fired
emergency fire pump engine.

The DAQ provided a response (DAQC-018-24) on January 8, 2024, acknowledging receipt of the
letter and concurring with Owens Corning’ request to waive all compliance actions and any
potential penalties associated with this instance of non-compliance conditional upon return to
compliance within 60 days of discovery or within a reasonable amount of time.

Owens Corning submitted a Notice of Intent (NOI) to the DAQ on February 29, 2024, to add
these unapproved diesel-fired engines to the AO and new AO DAQE-AN141780010-25,
including the engines, was issued on January 30, 2025.

Based on this information, the DAQ has determined that Owens Corning meets the criteria of the
Act and will waive civil penalties for these instances of noncompliance and pursue no further
action regarding this matter.

" / 2 / 6 Û á Û Ù Û Þ
DAQC-224-25
Page 2

If you have any questions regarding this letter, please contact me at [phone] or
[e-mail].

Sincerely,

Chad Gilgen, Manager
Minor Source Compliance Section

CG:rh

cc: Marina Thomas, Utah Attorney General’s Office