rigid landfill pit can capture leakage information within about 1a, and one pollution
monitoring well on the eastern side of the southern end can capture leakage
information in about 5a.
From the above calculation, it can be seen that as the target aquifer of the typical
site is characterized by poor permeability and weak dispersion, the pollution range
of the landfill due to groundwater immersion is small. Only when the pollution
control monitoring well is close to the point of failure can the typical pollutants in
the landfill pit enter the monitoring well under the convection or dispersion of
groundwater. If the pollution control monitoring well is far away from the point of
failure, no pollution information can be captured.
In order to find out the groundwater pollution caused by the damages of the
landfill pit timely and effectively, the monitoring wells must be arranged near the
location where the damage is most likely to occur. Then, determining where the
monitoring wells shall be arranged actually requires the probability distribution of
damages at different locations of the landfill pit. However, it is not clear where the
leakage may occur in the landfill except that there is extremely rich statistical data.
In this way, it can only be considered that the probability of damages of the landfill
pit at each location is the same. Therefore, the pollution control wells can monitor
pollution as long as they are close enough to the landfill.
For the typical site selected this time, we shall consider the physical properties of
its rigid structure, and analyze from the perspective of structural mechanics, and
arrange the pollution control monitoring wells at the location with the highest
probability of damages, as shown in Figs. 5.86, 5.87 and 5.88.
(3) Analysis of water quality items of existing monitoring wells
According to the requirements of the Technical Guide for Survey and Assessment of
Basic Environmental Conditions of Groundwater of the Hazardous Waste Disposal
Site (Draft), groundwater monitoring items have two major categories, including
required test items and optional test items. The required test indicators are:
① Natural background ions (required)
Potassium, calcium, sodium, magnesium, sulfate, chloride ion, carbonate,
bicarbonate
② Regular indicators (required)
pH value, dissolved oxygen, redox potential, conductivity, color, smell and taste,
turbidity, visible substances, total hardness, total dissolved solids, iron, manganese,
volatile phenols, anionic synthetic detergents, permanganate index, nitrate nitrogen,
nitrite nitrogen, ammonia nitrogen, fluoride, selenium and total escherichia coli.
③ Characteristic indicators (required)
Hexavalent chromium, zinc, copper, nickel, cadmium, lead, mercury, arsenic and
cyanide
According to the National Catalogue of Hazardous Wastes, the selected indicators are screened according to the characteristic pollution components of each
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319
monitoring well on the eastern side of the southern end can capture leakage
information in about 5a.
From the above calculation, it can be seen that as the target aquifer of the typical
site is characterized by poor permeability and weak dispersion, the pollution range
of the landfill due to groundwater immersion is small. Only when the pollution
control monitoring well is close to the point of failure can the typical pollutants in
the landfill pit enter the monitoring well under the convection or dispersion of
groundwater. If the pollution control monitoring well is far away from the point of
failure, no pollution information can be captured.
In order to find out the groundwater pollution caused by the damages of the
landfill pit timely and effectively, the monitoring wells must be arranged near the
location where the damage is most likely to occur. Then, determining where the
monitoring wells shall be arranged actually requires the probability distribution of
damages at different locations of the landfill pit. However, it is not clear where the
leakage may occur in the landfill except that there is extremely rich statistical data.
In this way, it can only be considered that the probability of damages of the landfill
pit at each location is the same. Therefore, the pollution control wells can monitor
pollution as long as they are close enough to the landfill.
For the typical site selected this time, we shall consider the physical properties of
its rigid structure, and analyze from the perspective of structural mechanics, and
arrange the pollution control monitoring wells at the location with the highest
probability of damages, as shown in Figs. 5.86, 5.87 and 5.88.
(3) Analysis of water quality items of existing monitoring wells
According to the requirements of the Technical Guide for Survey and Assessment of
Basic Environmental Conditions of Groundwater of the Hazardous Waste Disposal
Site (Draft), groundwater monitoring items have two major categories, including
required test items and optional test items. The required test indicators are:
① Natural background ions (required)
Potassium, calcium, sodium, magnesium, sulfate, chloride ion, carbonate,
bicarbonate
② Regular indicators (required)
pH value, dissolved oxygen, redox potential, conductivity, color, smell and taste,
turbidity, visible substances, total hardness, total dissolved solids, iron, manganese,
volatile phenols, anionic synthetic detergents, permanganate index, nitrate nitrogen,
nitrite nitrogen, ammonia nitrogen, fluoride, selenium and total escherichia coli.
③ Characteristic indicators (required)
Hexavalent chromium, zinc, copper, nickel, cadmium, lead, mercury, arsenic and
cyanide
According to the National Catalogue of Hazardous Wastes, the selected indicators are screened according to the characteristic pollution components of each
5.5 North China
319