FIGURE 16-1 Pathways for contamination.

FIGURE 16-2 Circumferential cutoff wall.

FIGURE 16-3 Upgradient vertical barrier.

FIGURE 16-4 Down-gradient vertical barrier.

FIGURE 16-5 Embedment of vertical barrier walls.

FIGURE 16-6 Soil-bentonite slurry trench cutoff wall construction schematic.

FIGURE 16-7 Slurry trench excavation.

FIGURE 16-8 Soil-bentonite backfill permeability test results.

FIGURE 16-9 Soil-bentonite backfill hydraulic conductivity.

FIGURE Grain size distribution for soil-bentonite backfill.

FIGURE Cement-bentonite permeability test results.

FIGURE Schematic of diaphragm slurry trench cutoff wall construction.

FIGURE Vibrated-beam cutoff wall.

FIGURE DSM augers used to construct a vertical barrier.

FIGURE Deep soil-mixed cutoff wall.

FIGURE Composite cutoff wall.

FIGURE Grouting of rock fractures.

FIGURE Potential defects in soil-bentonite slurry trench cutoff walls.

FIGURE Block displacement technique.

FIGURE Pump-and-treat performance data for Chem-Dyne Site,

FIGURE Single extraction well capture zone (not drawn to scale).

FIGURE Single extraction well capture zone (not drawn to scale).

FIGURE Partially penetrating single extraction well capture zone (not drawn to scale).

FIGURE Schematic of air sparging.

FIGURE NoVOCs well construction.

FIGURE Section of containment system at Love Canal.

FIGURE Biopolymer slurry trench.

FIGURE Schematic of SVE system.

FIGURE Schematic of soil/soil vapor model.

FIGURE An SVE system under construction.

FIGURE Effect of distance from vapor extraction well.

FIGURE Twin Cities Army ammunition plant ratio of withdrawal rate versus vacuum head.

FIGURE Twin Cities army ammunition plant vapor pressure drop versus distance.

FIGURE Effective radius of vacuum-influenced normalized pilot-test vacuum data plot.

FIGURE Trailer-mounted soil vapor extraction unit.

FIGURE Plume management for single extraction well, treatment wall curtain, and funnel-and-gate systems.

FIGURE Funnel and gate system configurations.