DSHW-2003-004103 - 0901a0688013f479

ATK
ALLIANT TECHSYSTEMS
Thiokol Propulsion Corp, Tel [phone]
RO, Box 707 Fax [phone]
Mav 22, 2003 Brigham City, UT 84302-0707
.00-PV04-ST0n rtfcCEIVfcL
Dennis R. Downs, Executive Secretary nANO D&dA\j^fiB\>
Division of Solid and Hazardous Waste Control Board xira A i ^
Department of Environmentai Quality DivisionoTSoil?i WA.. -yas
P. O. Box 144880 !,h r>tnarf::ipntnf rnuJfnnmi>i.r=, .', -•
Salt Lake City, Utah 84114-4880
Dear Mr. Downs
Subject: Response to Comments on Revised Soil Gas Survey, ATK Thiokol Propulsion
- Promontory Facility, # UTD009081357, dated April 21, 2003
In a letter dated April 21, 2003, the Utah Division of Solid and Hazardous Waste provided
comments to Thiokol Propulsion conceming a passive soil gas survey work plan. The
purpose ofthe comments was to settle a fe'w unresolved issues before plan approval by the
Division. Enclosed are our responses to those comments. We hope that these explanations
adequately address your concems, and that the Division will act swiftly to approve the plan ,
so that field work may be completed this Summer.
Thank you for your prompt consideration ofthis request. Ifyou have questions or need
additional information, please call John Holladay at 863-6895.
Sincerely
(w/{/ Kpwt/iib^
Paul V. Hancock, Manager
Environmental Remediation
Enclosure
The Division ofSolid and Hazardous Waste (the Division) has reviewed your responses to
our comments on the Passive Soil Gas Survey Work Plan. These responses were received
at our office on March 20, 2003. There are still a few unresolved issues that the Division
would like to settle before approving the Work Plan. These issues are addressed below:
3.2 Use and Limitations of Data
In your response to our original comment on this section ofthe plan, it is stated that "If the
technology is applicable to this location, we will likely first use soil gas as a screening
tool, and second with a tighter grid to search for locations for sampling of soils (hot
spots)." How will Thiokol determine "if the technology is applicable" at the SWMUs?
The technology will be considered applicable if positive values are reported by the
laboratory. The extent of applicability can only be determined from the reported results, and
how useful the tool is in helping locate contaminant hotspots. The technology is not
applicable if no or few positive values are reported.
If VOC soil gas is not detected, how will Thiokol differentiate between the absence of soil
gas and failure of the technology?
Soil gas will be used as a screening tool, and not as a compliance tool. If no or few positive
results are reported by the laboratoiy report, we will not assume that contamination is
absent, rather that the method is not applicable or the set-up and planning were inadequate.
Thiokol will also have QA/QC blanks to reduce some types of potential error.
4.1 Sampling Protocoi
Do drawings (constmction plans) exist for the septic drainfields at SWMU #625 that show
the drain lines, spacing, length etc.? If so, please submit them with you response.
We have included a copy ofthe soil gas survey plan drawing ofSWMUM25 with drainlines
and RFI boreholes imposed upon the proposed grid. However, the old drawings these were
adapted from are not precise enough to be certain ofthe exact placement of drainfield lines
or boreholes.
Please submit your response to these questions within 30 calendar days ofthe date ofthis
letter. Ifyou have any questions regarding this letter, please contact Jeff Vandel at 538-9413.
Thank you for you cooperation.
RDCKET DISPLA
• RFI SAMPLE BORING LDCATIDN
ENVIRONMENTAL
SERVICES
SEPTIC DRAINFIELDS
SOIL GAS GRID
SWMU #625
FED ND, SCALE
l"=200'i
DRAWING ND, REV,
625-1 A.DWG