of “when one boundary of the disposal site is perpendicular to the groundwater flow
direction or the minimum included angle between them is less than 10°” and “one
borehole shall be located 80–120 m downstream of the groundwater flow direction
of the disposal site”.
(2) Rationality and effectiveness analysis of existing monitoring wells
A total of 6 monitoring wells shall be provided at the typical site for monitoring the
groundwater environment of the target aquifer, including 1 full-field background
monitoring well, 1 full-field diffusion monitoring well, 1 landfill background
monitoring well and 3 landfill pollution monitoring wells.
According to the analysis of the distribution of hazardous waste disposal units of
the typical site, the existing monitoring wells at the typical site only monitor
leakage from the rigid landfill pit, without considering other disposal units that may
pollute the groundwater environment. On the other hand, the background monitoring wells and diffusion monitoring wells of the typical site do not take into
account the flow field conditions of the target aquifer. Therefore, the layout of
existing monitoring wells of the typical site is not very reasonable. This section will
briefly and generally analyze whether the existing monitoring wells can effectively
monitor and capture the pollutants in the landfill after they enter the target aquifer.
With the help of the calculation function of numerical simulation software, the
collected aquifer permeability coefficient, porosity and dispersion coefficient are not
adopted for the parameter calibration, but substituted into the numerical model
based on the flow field in June 2015, so as to briefly analyze the capture of the
particular pollutant Pb by the existing groundwater monitoring, and demonstrate
and showcase the effectiveness and rationality of existing monitoring wells. The
technical route of numerical simulation and analysis is shown in Fig. 5.79. The
distribution of locations of the existing monitoring wells at the site is shown in
Fig. 5.80.
① Conceptual hydrogeological model of groundwater pollution migration
The generalization of hydrogeological conditions is to generalize a complex
hydrogeological unit to one that can be simulated by existing mathematical methods
based on the conceptual model of the groundwater system and through certain
synthesis and induction. The generalized model shall reflect the main functions of
hydrogeological prototype and shall be feasible and economical in mathematical
treatment. We generalize the study area into a conceptual model of inhomogeneous isotropy, spatial three-dimensional structure and stable groundwater
flow. The steady flow field is set at the fixed head boundary, and the
water-resisting boundary is perpendicular to the groundwater contour.
Atmospheric precipitation infiltration and evaporation are not considered on
the boundary.
312
5 Application Cases
direction or the minimum included angle between them is less than 10°” and “one
borehole shall be located 80–120 m downstream of the groundwater flow direction
of the disposal site”.
(2) Rationality and effectiveness analysis of existing monitoring wells
A total of 6 monitoring wells shall be provided at the typical site for monitoring the
groundwater environment of the target aquifer, including 1 full-field background
monitoring well, 1 full-field diffusion monitoring well, 1 landfill background
monitoring well and 3 landfill pollution monitoring wells.
According to the analysis of the distribution of hazardous waste disposal units of
the typical site, the existing monitoring wells at the typical site only monitor
leakage from the rigid landfill pit, without considering other disposal units that may
pollute the groundwater environment. On the other hand, the background monitoring wells and diffusion monitoring wells of the typical site do not take into
account the flow field conditions of the target aquifer. Therefore, the layout of
existing monitoring wells of the typical site is not very reasonable. This section will
briefly and generally analyze whether the existing monitoring wells can effectively
monitor and capture the pollutants in the landfill after they enter the target aquifer.
With the help of the calculation function of numerical simulation software, the
collected aquifer permeability coefficient, porosity and dispersion coefficient are not
adopted for the parameter calibration, but substituted into the numerical model
based on the flow field in June 2015, so as to briefly analyze the capture of the
particular pollutant Pb by the existing groundwater monitoring, and demonstrate
and showcase the effectiveness and rationality of existing monitoring wells. The
technical route of numerical simulation and analysis is shown in Fig. 5.79. The
distribution of locations of the existing monitoring wells at the site is shown in
Fig. 5.80.
① Conceptual hydrogeological model of groundwater pollution migration
The generalization of hydrogeological conditions is to generalize a complex
hydrogeological unit to one that can be simulated by existing mathematical methods
based on the conceptual model of the groundwater system and through certain
synthesis and induction. The generalized model shall reflect the main functions of
hydrogeological prototype and shall be feasible and economical in mathematical
treatment. We generalize the study area into a conceptual model of inhomogeneous isotropy, spatial three-dimensional structure and stable groundwater
flow. The steady flow field is set at the fixed head boundary, and the
water-resisting boundary is perpendicular to the groundwater contour.
Atmospheric precipitation infiltration and evaporation are not considered on
the boundary.
312
5 Application Cases