2007-11-20_REVISION - M1982015 ‎(12)‎

• Permit No: M1982015
• IBM Index Class Name: REVISION
• Doc Date: 11/20/2007
• Doc Name: Integrated Corrective Action Plan
• From: E-21 Engineering, Inc.
• To: DRMS
• Type & Sequence: TR3
• Media Type: D
• Archive: No

t results from the test pit sampling are summarized in Table 3. The laboratory
reports are included in Appendix 3.
Waste Characterization Sampling
On December 19, 2006, E-21 re-sampled the contents of the SHT and collected
' a sample of free water from the top of the slurry. This was performed to
determine the waste disposal strategy. The water sample was collected using 40
milliliter VOA vials. The slurry sample was collected as a composite of material
' as best as possible from the lower portion of the SHT from four locations. The
samples were placed in a cooler with ice and were submitted to ECS for BTEX
and TVPH analysis by EPA Method 8260B.
Based on the lab results, the benzene concentration in these samples was 400
mg/Kg in the slurry phase and 30,000 ug/L in the water phase. At the time of the
sampling, there was approximately 6 to 12 inches of water covering most of SHT
with a relatively thin ice layer covering it. The slurry contained a strong gasoline
odor and exhibited a sheen in most places. The slurry sample was analyzed for
TCLP to determine waste disposal acceptance at various landfills in the area.
' The result was 12 mg/L. The results of the SHT and water sampling are
summarized in Table 5 and 5A. The laboratory reports are included in Appendix
3.
' The SHT was approximately 400 feet in length and ranged in depth from 3 feet
on the east end to over 8 feet to the west in places. It was approximately 4 feet
in width. Approximately 70,000 gallons of petroleum-impacted slurry and water
' was estimated to be present in the holding trench. Detail of the Slurry Holding
Trench is illustrated on Figure 3
' Contaminated Slurry Removal and Disposal Activities
On January 9, 2007, E-21 contracted ThermoFluids to pump out and transport
' the water/slurry to Arvada Treatment Center in Arvada, Colorado. However, due
to heavy snow falls and low temperatures since December 23, 2006, there was a
thick layer of ice and snow on the SHT. The ice and snow was cleared by an
excavator provided by GeoCon and pumping was attempted. Approximately
1,500 gallons of water/slurry mixture was removed by the vac truck. But due to
the ice and snow in the trench, pumping of free water was slow and difficult. The
liquids were transported to Arvada Treatment Center. After unloading the
' water/slurry liquids, 3,000 pounds of silt and sand was present in the bottom of
the vac truck. This material was returned to the SHT the next day by
ThermoFluids. In addition, Arvada Treatment Center would not accept further
' shipments of the water from the site due to the high particulate content. Thus,
pumping was discontinued.
Soil Stabilization and Sampling Activities
' On January 9, 2007, soil and slurry stabilization efforts began. In the effort to
move water and slurry to the west end of the SHT for pumping, an excavator
' provided by GeoCon pushed slurry from the east end of the trench to the west.
Approximately 50% of the slurry was moved from a 100-foot length of the east
end of the SHT between station markers 23+00 to 22+00, thus, leaving
' approximately 8,000 gallons of slurry in the trench. This material was
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