Kouli_etal_2008_Groundwater modelling_BOOK.pdf - Pantelis ...

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Sabrina Saponaro, Sara Puricelli, Elena Sezenna et al.
Surface sealing
Fig. 15(b) shows results at stationary conditions about the simulation where the surface
sealing was applied, and only P SVE was operating with an extraction flow rate Q V,SVE,pil . Air
pressure range in the color scale is set to let a direct comparison with Fig. 9(d), even if lower
values (up to 1.0113 10 5 Pa) are obtained with sealing. Atmospheric air is sucked no more
into soil; beneath sealing (continuous horizontal green line), air flows along X direction,
without crossing the impermeable layer. At half depth of the screen (-8.5 m g.s.) in the
monitoring wells PZ SVE1 , PZ SVE2 and PZ SVE3 [Fig. 16(a)], the air pressure [Fig. 16(c)] is lower
than without sealing [Fig. 16(b)]; at this depth, the amplitude of ZOT SVE (ΔP g ≥ 25 Pa) is 5.1
m, about twice the value obtained without sealing (2.6 m).
Figure 16. Air pressure P g at steady state over a section parallel to the XY plane passing at half depth of
the screen in the monitoring wells PZ SVE1 , PZ SVE2 and PZ SVE3 [(a)], when P SVE is operating at Q V,SVE,pil .:
(b) without surface sealing; (c) with surface sealing.
Figure 17. Air saturation S g at stationary conditions over horizontal sections parallel to the XY plane
(a). The simulated plant is composed by four AS wells, each one operating at Q V,AS,pil , screened as P AS ,
and 4.5 m far. Sections show results at different planes: α at -23 m g.s. (b), β at -22.3 m g.s. (c), γ at -
18.5 m g.s. (d) and δ at -15.0 m g.s. (e). The dashed brown rectangle delimits pollution in soil.