Continuous wall (plan view)
Groundwater flow
Reactive media
Groundwater-monitoring well
Reactive media
Screening location of
groundwater well
Reactive
media
Groundwater-monitoring well
A
A
B
B
C
C
E
E
E
D
D
Groundwater flow
Funnel-and-gate (plan view)
Section view
52
Permeable Reactive Barrier
between the caisson gate and the funnel wall in a funnel-and-gate system is
an important consideration.
3.2.4 Performance Monitoring
Performance monitoring GW well locations for the PRB are generally focused
on the PRB system itself rather than on the entire site or the compliance
boundaries (Figure 3.5). Traditional GW sampling approaches often result in
withdrawal of a large volume of water that might compromise the PRB sampling objective. Consequently (Gavaskar et al. 2000), passive or semi-passive
GW sampling approaches are recommended (Powell and Puls 1997). The
performance monitoring program should be designed to detect changes in
FIGURE 3.5
Locations of the performance monitoring groundwater well for continuous and funnel-andgate PRBs configurations. (Reproduced with permission from Carey, M.A. et al. 2002. Guidance
on the use of permeable reactive barriers for remediating contaminated groundwater. National
Groundwater and Contaminated Land Centre report NC/01/51 P.69.)