DSHW-2007-007590 - 0901a0688016327d (4)

David P. Gosen, P.E.
Director, Environmental Services
ATK Thiokol-Promontory
P.O. Box 707
Brigham City, UT 84302-0707

Subject: Hazardous Waste Management Unit (HWMU) I-10
Closure Certification Report
ATK Launch Systems-Promontory Facility, EPA I.D. #UTD009081357

Dear Mr. Gosen:

The final closure certification report for HWMU I-10 is hereby verified. HWMU I-10 was a small burn cage used to treat small amounts of waste. At the time of closure, the burn cage
and residual waste were removed. Following the removal, confirmation samples were collected and analyzed for explosives, volatile organics, metals and perchlorate, but semi-volatiles
were not a sample parameter. Following confirmation sampling at closure, the site was covered with soil fill.

Upon review of the closure certification report, the Division identified the data gap related to semi-volatile (SVOC) sample data as indicated above. To fill this data gap and resolve
outstanding issues related to possible releases of poly aromatic hydrocarbons (PAHs) from burning at this small site, the Division collected four soil samples. Two samples were analyzed
for SVOCs by EPA Method 8270 and two samples were analyzed for total metals by EPA Method 6010. The sample results are enclosed with this letter.

A historical photo was used to re-locate the burn cage and burn area, and a shovel was used to remove the fill material in the area of the former burn cage. After removing the fill,
a small amount of black stained soil was observed, and samples were collected in the area of the stained soil. The sample results show that PAH and other SVOC contamination was not
detected and metals contamination was not detected at concentrations above the EPA Preliminary Remediation Goals (see http://www.epa.gov/region09/waste/sfund/prg/).

This site now qualifies for residential use or No Further Action (NFA) as described in R315-101.

The closure process is now complete for HWMU I-10.

If you have any questions, please contact Jeff Vandel or Dave Larsen at [phone].

Sincerely,

ORIGINAL DOCUMENT SIGNED BY DENNIS R. DOWNS ON 11/02/07

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

DRD/DCL/tjm

Enclosure: F:\WP\Thiokol Burn area samples.xls

c: Lloyd C. Berentzen, MBA, Health Officer, Bear River Health Department
Tom Burns, Region 8 USEPA
Kathy Barker, DSHW

November 2, 2007
Page 2

November 2, 2007

TN200701142
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

State of Utah

Department of Environmental Quality

Richard W. Sprott
Executive Director

DIVISION OF SOLID AND HAZARDOUS WASTE
Dennis R. Downs
Director

JON M. HUNTSMAN, JR.
Governor

GARY HERBERT
Lieutenant Governor