DSHW-2008-025222 - 0901a068801e2220 (4)

November 3, 2008

Dave P. Gosen, P.E.
Director, Environmental Services
ATK Launch Systems – Promontory
P.O. Box 707
Brigham City, UT 84302-0707

RE: Operation and Maintenance Inspection
ATK Launch Systems – Promontory Facility, EPA I.D. #UTD009081357

Dear Mr. Gosen:

On May 22, 2008, staff members of the Division of Solid and Hazardous Waste (the Division) conducted an Operation and Maintenance Inspection (O&M) of the ATK Launch Systems – Promontory
(ATK) groundwater monitoring system. This inspection was conducted in order to evaluate ATK’s operation and maintenance of the groundwater monitoring system and compliance with the
Post-Closure Permit (the Permit). A copy of the inspection report is enclosed with this letter. Based upon our evaluation, the Division has identified four issues of concern. These
issues are discussed below.

1. Based on information provided by ATK, wells A-8, A-9, B-7 and C-4 are currently not operational since the dedicated pump for each well no longer works. Permit Condition IV.D.1.b.
states that existing monitoring wells shall be maintained in a fully operational condition for the duration of the permit. Please identify how ATK plans to address this issue. In addition,
please provide an evaluation of the condition of the screens for these wells.

2. Permit condition IV.D.2.a. states that well construction shall follow the techniques described in the EPA Technical Enforcement Guidance Document (TEGD). According to the TEGD, it
is recommended that monitoring well screens not exceed ten feet in length. Based on the “Monitoring Well X-5 Installation Report” that was submitted by ATK, well X-5 was completed with
a 20-foot well screen. Please explain why a 20-foot screen was used in well X-5.

3. Based on available potentiometric surface data, it is unclear which direction groundwater is flowing in the extreme northeast area of the facility. It appears that groundwater elevation
drops from 4.372 feet at well P-5 to 4,349 feet at well P-1 indicating an easterly flow of groundwater in the area. In the past, ATK has shown on potentiometric surface maps that groundwater
flows in a southerly direction in this area. Since ATK will be collecting current potentiometric surface data from the wells in this area this Fall, please ensure that ATK evaluates
this issue after the data is collected.

4. Significant contamination has been detected in well J-4. Based on the concentrations of TCE that have been detected, it appears that the concentrated plume observed at wells A-8,
B-1 and E-9 down-gradient of the M-136 burn grounds, may move in a southeasterly direction towards well J-4. It’s apparent that more information is needed for this area. The Division
and ATK personnel have discussed installing an additional well to help define the extent of contamination in the area. The Division is also aware that ATK has initiated a borescope
survey in the well to help determine the direction of groundwater flow. Please provide a proposal and schedule for evaluating the extent of contamination in this area.

Please submit to the Division, within 30 days of the date of this letter, responses to the four issues identified above. If you have any questions, please contact Jeff Vandel at 538-9413.

Sincerely,

ORIGINAL DOCUMENT SIGNED BY DENNIS R. DOWNS ON 11/03/08

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

DRD/JV/tjm

Enclosure

c: Eric Johnson, US EPA Region VIII
Paul Hancock, ATK Launch Systems
Lloyd Berentzen, Deputy Director, Bear River Health Department

File to: ATK Launch Systems - Promontory

November 3, 2008
Page 2
TN200800955

288 North 1460 West • Salt Lake City, UT
Mailing Address: P.O. Box 144880 • Salt Lake City, UT 84114-4880
Telephone [phone] • Fax [phone] • T.D.D. [phone]
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TN200800955 Printed on 100% recycled paper

State of Utah

JON M. HUNTSMAN, JR.
Governor

GARY HERBERT
Lieutenant Governor

Department of Environmental Quality

Richard W. Sprott
Executive Director

DIVISION OF SOLID AND HAZARDOUS WASTE
Dennis R. Downs
Director