DSHW-2004-007537 - 0901a06880160757 (4)

Paul Hancock, Environmental Remediation Manager
ATK Thiokol Propulsion – Promontory
P.O. Box 707
Brigham City, UT 84302-0707

RE: Class 2 Post-Closure Permit Modification #03.03906
ATK Thiokol Propulsion – Promontory
EPA ID #UTD009081357

Dear Mr. Hancock:

This letter is in response to Thiokol’s Monitoring Well Installation Plan and your request to modify the Post-Closure Permit (the Permit), which was received November 25, 2003. The
Permit modification is necessary in order to incorporate changes in Thiokol’s groundwater monitoring system. The Monitoring Well Installation Plan (the Plan) is required, in accordance
with Permit condition V.D.2.b., when new wells are installed.

The Plan is hereby approved. The Monitoring Well Completion Report needs tol be submitted to the Division within 90 days of completing well installations, as indicated in Section 2.6
of the Plan.

The Class 2 Permit Modification is also approved. A 60-day public comment period was held from November 13, 2003 to January 12, 2004, and a public information meeting was held on December
11, 2003. No comments were received from the public regarding the permit modification. The necessary changes to the Permit have been made, and the pages affected by the modification
are enclosed with this letter. Please replace the old pages of the Permit with those enclosed.

If you have any questions, please contact Jeff Vandel at 538-9413. Thank you for your cooperation.

Sincerely,

ORIGINAL DOCUMENT SIGNED BY DENNIS R. DOWNS ON 4/1/04

Dennis R. Downs, Executive Secretary
Utah Solid and Hazardous Waste Control Board

DRDJV\ts

Enclosure: Module V.Attachment 4

c: John C. Bailey, M.D., M.S.P.H., Health Officer/Director, Bear River Health Dept.
Linda Bowling, USEPA Region VIII

TN200400206
File to: ATK Thiokol Propulsion – Promontory

April 1, 2004
Page 2

State of Utah

Department of Environmental Quality

Dianne R. Nielson, Ph.D.
Executive Director

DIVISION OF SOLID & HAZARDOUS WASTE
Dennis R. Downs
Director

OLENE S. WALKER
Governor

GAYLE F. McKEACHNIE
Lieutenant Governor

April 1, 2004

288 North 1460 West • PO Box 144880 • Salt Lake City, UT 84114-4880 • phone [phone] • fax [phone]
T.D.D. [phone] • www.deq.utah.gov