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6394314 
Book/Book Chapter 
Design and construction of a jet-grouted barrier wall 
White, DM; Koelling, M; Ashcom, DW; Kurrus, J 
1999 
GEOTECHNICAL SPECIAL PUBLICATION 
90 
1027-1038 
WOS:000084506700083 
An innovative application of jet-grouting technology has been successfully used to construct a below-grade barrier wall to contain petroleum hydrocarbon contamination in Spokane, Washington. The wall was constructed to intercept the flow of groundwater and Bunker C fuel. Bunker C, a heavy petroleum hydrocarbon flowed slowly downgradient over a period of years from underground storage tanks at a steam plant operated by a Spokane utility. A 540-foot-long hydrocarbon plume was delineated, hydrocarbons and groundwater flow through a permeable sand and gravel formation within troughs in relatively impermeable bedrock and fine silt. A 280-foot-long wall was constructed as a hydraulic barrier to intercept hydrocarbons and control groundwater flow. The wall consisted of overlapping columns of jet grouted Soilcrete, which reduced the permeability of the sand and gravel formation by approximately four orders of magnitude. The wall was anchored into the bedrock and silt, with a base elevation at depths ranging from 26 to 52 feet below grade and with a top elevation at 25 feet below grade. The height of the wall was varied to provide a level top, with the exception of an area left 2 feet lower to serve as a below-grade weir. A subsurface pumping system (hydraulic control system) allows the removal and treatment of the groundwater on the upgradient side of the barrier and disposal of the treated water into the municipal wastewater-collection system. Instrumentation associated with the pumping system allowed documentation of the effectiveness of the wall at maintaining the negative head differential. A SCADA system allows monitoring and control of this system from remote locations. Jet grouting allowed the wall to be constructed with a minimum of disruption to traffic on a busy downtown street, while working within an area of multiple utilities. The paper documents construction of the barrier wall and early operation of the hydraulic control system to verify the functionality of the wall. Additional data concerning the time-related strength gain characteristics of the soil-cement-flyash-bentonite mix that forms the Soilcrete also is presented.