4. Source severity evaluation of the informal landfill
(1) Pollution source hazardous classification
① Indicators, weights and scores
Based on the evaluation method described in Sect. 3.2.2.1, the capacity scale (Y1) of
the informal landfill is 23.7 Â 10
4 m
3 and given a score of 4; the buried period (Y2)
is 8 years, given a score of 8; the leachate production volume (Y3) is [blank]: the
waste type (Y4) is mixed domestic refuse and construction waste, given a score of 6;
the anti-seepage condition (Y5) is natural soil layer, rated with a score of 10; the
leachate treatment status (Y6) is without any collection system, given a score of 10;
The weighted sum of the above factors is the overall hazardous index of the
domestic refuse landfill:
S ¼ b 1 Â Y1 þ b 2 Â Y2 þ b 3 Â Y3 þ b 4 Â Y4 þ b 5 Â Y5 þ b 6 Â Y6
S ¼ 0:3130 Â 4 þ 0:2049 Â 8 þ 0:1707 Â blank
½
þ0:1262 Â 8 þ 0:0993
 10 þ 0:0861  10
Case 10 Groundwater pollution survey, source severity assessment and risk
assessment of an informal landfill in Beijing
1. Overview of the study area
(1) Natural geography overview
① Natural geographical conditions
Beijing is located at the northern end of the North China Great Plain, 150 km from
the west shore of the Bohai Sea, facing mountains on one side and the sea on the
other. The city has a total area of 16,410.54 km
2 and is divided into 16 administrative districts. Geographical coordinates: 115° 25′–117° 30′ E, 39° 28′–41° 05′ N.
The Beijing Plain is formed mainly by the alluvial and deluvial effects of rivers
such as Yongding River, Wenyu River and Chaobai River; It is adjacent to
mountains on the east, west and north sides and an inclined plain on the southeast.
Alluvial fan is well-developed on the piedmont. Depressions, rivers, natural dikes
and river terraces are widely distributed in the plain area. The average elevation of
Beijing is 43.5 m. The altitude of the plain area is between 20 and 60 m, and that of
the mountainous areas is generally between 500 and 1500 m.
② Weather
The Beijing-Tianjin-Hebei region is located on the eastern side of the mid-latitude
Eurasia. Its climate is typical warm temperate semi-humid semi-arid continental
monsoon climate: dry and windy in the spring with quick bouncing back of temperature; hot and rainy in the summer; sunny and cool in the autumn; cold and dry
in winter, with much wind and little snow. The annual average temperature is
11–12 °C, and the monthly average wind speed is the largest in April in the spring.
262
5 Application Cases
(1) Pollution source hazardous classification
① Indicators, weights and scores
Based on the evaluation method described in Sect. 3.2.2.1, the capacity scale (Y1) of
the informal landfill is 23.7 Â 10
4 m
3 and given a score of 4; the buried period (Y2)
is 8 years, given a score of 8; the leachate production volume (Y3) is [blank]: the
waste type (Y4) is mixed domestic refuse and construction waste, given a score of 6;
the anti-seepage condition (Y5) is natural soil layer, rated with a score of 10; the
leachate treatment status (Y6) is without any collection system, given a score of 10;
The weighted sum of the above factors is the overall hazardous index of the
domestic refuse landfill:
S ¼ b 1 Â Y1 þ b 2 Â Y2 þ b 3 Â Y3 þ b 4 Â Y4 þ b 5 Â Y5 þ b 6 Â Y6
S ¼ 0:3130 Â 4 þ 0:2049 Â 8 þ 0:1707 Â blank
½
þ0:1262 Â 8 þ 0:0993
 10 þ 0:0861  10
Case 10 Groundwater pollution survey, source severity assessment and risk
assessment of an informal landfill in Beijing
1. Overview of the study area
(1) Natural geography overview
① Natural geographical conditions
Beijing is located at the northern end of the North China Great Plain, 150 km from
the west shore of the Bohai Sea, facing mountains on one side and the sea on the
other. The city has a total area of 16,410.54 km
2 and is divided into 16 administrative districts. Geographical coordinates: 115° 25′–117° 30′ E, 39° 28′–41° 05′ N.
The Beijing Plain is formed mainly by the alluvial and deluvial effects of rivers
such as Yongding River, Wenyu River and Chaobai River; It is adjacent to
mountains on the east, west and north sides and an inclined plain on the southeast.
Alluvial fan is well-developed on the piedmont. Depressions, rivers, natural dikes
and river terraces are widely distributed in the plain area. The average elevation of
Beijing is 43.5 m. The altitude of the plain area is between 20 and 60 m, and that of
the mountainous areas is generally between 500 and 1500 m.
② Weather
The Beijing-Tianjin-Hebei region is located on the eastern side of the mid-latitude
Eurasia. Its climate is typical warm temperate semi-humid semi-arid continental
monsoon climate: dry and windy in the spring with quick bouncing back of temperature; hot and rainy in the summer; sunny and cool in the autumn; cold and dry
in winter, with much wind and little snow. The annual average temperature is
11–12 °C, and the monthly average wind speed is the largest in April in the spring.
262
5 Application Cases