DSHW-2006-010418 - 0901a0688016233e

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

RE: Pilot-Test Work Plan to Evaluate Enhanced Anaerobic Bioremediation of Perchlorate and Solvent Contaminated Groundwater, ATK Launch Systems - Promontory Facility, EPA I.D. #UTD009081357

Dear Mr. Gosen:

The Division of Solid and Hazardous Waste has completed its review of the ATK Promontory Pilot Study Work Plan, referred to above, that was prepared by EarthFax Engineering, Inc. and
submitted to our office on August 4, 2006. According to the Work Plan, the objective of the Pilot Test is to evaluate enhanced in-situ anaerobic bioremediation of perchlorate and solvent
contaminated groundwater at an area within the M-136 Burn Grounds.

The ATK Liquid Thermal Treatment Area (M-136 Burn Grounds) Post-Closure Permit requires that corrective action be taken to clean up contaminated groundwater at the facility. If the
Pilot Test is successful, this technology may be used to comply with this requirement.

Attached to this letter are several questions and comments that the Division has regarding the Work Plan. A written response to these questions and comments is needed before approval
for the Pilot Test can be given. Please provide your response within 30 days of receipt of this letter.

November 8, 2006
Page 2

If you have any questions, please contact Jeff Vandel at 801 538-9413.

Sincerely,

ORIGINAL DOCUMENT SIGNED BY DENNIS R. DOWNS ON 11/08/06

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

DRD\JV\tm

Enclosure

c: Lloyd C. Berentzen, M.B.A., Health Officer/Director, Bear River Health Dept.
Tom Aalto, USEPA Region VIII
Paul Hancock, ATK

File to: ATK Launch Systems – Promontory

PILOT TEST WORK PLAN COMMENTS

1.2 Site Conditions

Please provide the following additional information on wells A-1 and T-2 (as available): well logs, potentiometric surface, screen intervals, well development information, pump test
results, and current condition of the wells.

Pilot Test Design

Where did the figure for hydraulic conductivity (500 to 700 ft/day) come from? Please provide a reference.

In regard to the injection of sodium bromide tracer, will it continue to be mixed with pumped groundwater and injected after it is detected in well T-2?

Sampling and Analysis

The condition of all of the monitoring wells that are anticipated to be sampled during the pilot test should be checked prior to sampling and the wells should be redeveloped as needed.

The Work Plan states that selected samples will be collected during the test and analyzed for nitrate, sulfate and other compounds (second paragraph, page eight). What will the selection
of samples, that will be analyzed for these compounds, be based on?

Data Management, Analysis, and Interpretation

Please include a brief evaluation on the impact to water quality from the injection of soybean oil once the analytical data has been interpreted.

Residuals Management

Please be aware that any groundwater from the treatment zone that isn’t injected into the aquifer must be managed as hazardous waste due to the presence of listed constituents.

Appendix A

In regard to the calculations for estimating the quantity of soybean oil that will be required:

1) Is secondary porosity accounted for in the porosity figures used (shown under the heading “Hydraulic Characteristics”)?

2) Where did the concentrations for the background compounds (nitrate, etc.) come from that were used to determine the background hydrogen demand?

November 8, 2006

TN200601292
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

Dianne R. Nielson, Ph.D.
Executive Director

DIVISION OF SOLID AND HAZARDOUS WASTE
Dennis R. Downs
Director

JON M. HUNTSMAN, JR.
Governor

GARY HERBERT
Lieutenant Governor