DSHW-2011-007368 - 0901a068802545e1

Launch Systems Group
P.O. Box 707
Brigham City, UT 84302
www.atk.com
25 July 2011
8200-FYl 2-021
Scott T Anderson
Executive Secretary,
c/o UDEQ Division of Solid and Hazardous Waste
PO Box 144880
SALT LAKE CITY UT 84114-4880
RECEIVED
JUL 2 7 2011
UTAH DIVISION Ul^
SOLID & HAZARDOUS WASTt
JlOII.OIlH'l
Subject: Response to Additional Division Comments on Corrective Measure Pilot Test Reports Ex-
Situ Soil and In-Situ Groundwater ATK Launch Systems Promontory Facility, EPA ID
#UTD009081357
Dear Mr. Anderson
Enclosed, please find responses to the Division's July 7, 2011 comments on two ATK Launch
Systems Promontory reports, "Evaluation of the Enhanced Bioremediation Pilot Test" and
"Corrective Measure Pilot Test to Evaluate Ex-Situ Remediation of Perchlorate Contaminated Soil.
Please contact Paul Hancock at [phone] if you have any comments or questions.
Sincerely,
^^^^^ -l^ac^
David P. Gosen, P.E., Director
Environmental Services
Response to Division of Solid and Hazardous Waste July 7,2011 Comments on Evaluation
of the Enhanced Bioremediation Pilot Test/Corrective Measures Pilot Test to Evaluation
Ex-Situ Remediation of Perchlorate Contaminated Soil
1) Comment 1: The text states that ATK has developed the ex-situ process to greatly limit the
probability of a release of raw bioreactor effluent to natural waterways, even if the chemical
oxygen demand (COD) is elevated. Is this reduced probability quantifiable?
Response: The ex-situ process used sealed roll-off bins to totally contain the soil and liquid bio-
reactor effluent. The bins were also placed in an area with secondary containment. This
arrangement does not lend itself to a quantitative determination but rather a qualitative
detennination that it limited the potential for a release to a storm charmel.
2) Comment 5: The text states that ATK did not perform statistical significance testing on the
slope of the estimated equation because it was concluded that the decay rate had accelerated.
However, we recommend that, in the future, rigorous statistical testing be routinely conducted,
because such testing can diminish subjective interpretations of the data and serve as a
verification tool for planning of follow-up tests.
Response: We concur that statistical significance testing in the future should be included as part
of the process used to verify an injection program.
3) Comment 6: The text states that the Division was correct in mentioning that the intended
purpose of wells D-2, T-2, and C-2 was not clear. While we understand the purpose of wells C-2
and T -2, the inclusion of monitoring well D-2 is still unclear to us. Please provide further details
on the purpose of well D-2.
Response: Well D-2 was included in the evaluation because of its proximity to the test area. It
was not known if fracture patterns in the limestone would extend to this well but was assumed
that no impact would be seen. Well D-2 represents conditions not impacted by vegetable oil
injection and therefore showed no response to anaerobic degradation following injection of the
vegetable oil.
4) Comment 7: The text states if vinyl chloride is released to water, it will rapidly evaporate.
Do you mean surface water, or do you mean air? Please clarify.
Response: The text refers to surface water in the form of a river 1 meter deep. The text from the
EPA Fact Sheet was included to illustrate the volatile nature of vinyl chloride.