DSHW-2003-007132 - 0901a068801603c1

September 29, 2003

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

RE: Indoor Air Sampling at the ATK Thiokol Propulsion – Promontory Facility, #UTD009081357

Dear Mr. Hancock:

In March of 2003, ATK Thiokol Propulsion (Thiokol) provided the Division of Solid and Hazardous Waste (the Division) with analytical data for indoor air samples that were collected at
the bottom of the pit at the north end of the M-508 high bay. The sample results indicated that TCE vapor was present in the pit at concentrations up to 1.4 mg/m3. The concentrations
detected, in eight out of a total of eleven samples, are significant and depending on the extent of vapor in the building, could pose a risk to human health. It appears that OSHA standards
do not apply in this case since TCE based solvent is no longer used at M-508 and workers could be exposed to the vapor (without their knowledge) simply by being in the building.

It is understood that workers rarely enter the pit at M-508 where the air samples were collected. In April of this year, staff members for the Division and Thiokol discussed collecting
additional indoor air samples in areas at M-508 where workers are commonly present to assess the potential for worker exposure to TCE vapor in the building. In addition, Thiokol was
asked to propose a plan for collecting indoor air samples in an e-mail sent by Jeff Vandel to you and John Holladay on April 30, 2003. This letter is written to remind Thiokol that
this potential threat to human health needs to be investigated.

The Division requests that Thiokol submit a plan for collecting indoor air samples that is designed to assess this potential health risk at Building M-508 by October 31, 2003. The Division
also recommends that Thiokol consider performing indoor air sampling at other buildings near or within the confines of the contaminant plume, such as E-519, where organic vapors may
be a concern. Guidance for indoor air sampling and methods of sampling and analysis were discussed in April.
If Thiokol needs to revisit the guidance, please contact Jeff Vandel at 538-9413. Thank you for your cooperation.

Sincerely,
Original Document Signed by Dennis R. Downs on 9/29/03

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

DRD\jv\kk

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

TN200302047
file to: ATK Thiokol Propulsion – Promontory

September 29, 2003
Page 2

Michael O. Leavitt
Governor
Dianne R. Nielson, Ph.D.
Executive Director
Dennis R. Downs
Director

Department of Environmental Quality
Division of Solid and Hazardous Waste
288 North 1460 West
P.O. Box 144880
Salt Lake City, Utah 84114-4880
[phone]
[phone] Fax
[phone] T.D.D.
www.deq.utah.gov