of fissure water and has low depth to water table, so it is prone to leakage of landfill
leachate. Once the groundwater is contaminated, pollutants migrate, transform, and
spread through groundwater flows.
– Receptors
According to the landfill use and the surrounding population, groundwater pollutants will pose hazards to the exposed workers of the site and residents of the
surrounding areas, so workers inside the site are considered as in situ sensitive
receptors considered and residents around the site as off-site sensitive receptors.
• Exposure pathway analysis
Since the site contamination plume involves groundwater-based drinking water
sources, the exposure pathways for in situ receptors include indoor and outdoor
inhalation of vapor from groundwater and groundwater intake. For off-site receptors, there are four pathways of exposure: indoor inhalation of off-site vapor from
groundwater, outdoor inhalation of off-site vapor from groundwater, outdoor
inhalation of off-site vapor from groundwater, and groundwater intake (Fig. 5.13).
(d) Risk characterization
The risk characterization is based on the observed content of pollutants in the
groundwater. Human exposure parameters (mainly for adults) are selected in
China’s context and calculated separately with reference to the values for sensitive
and non-sensitive land recommended in the Technical Guidelines for Risk
Assessment of Contaminated Sites (HJ25.3–2014). The parameters include phosphorus and fluorine.
Using the HERA model for risk assessment, the hazard quotient through adult
exposure pathways is calculated, and the results are as shown in Table 5.35.
• Pollutant-specific results of hazard quotient
As shown in Table 5.35, the hazard quotient of both phosphorus and fluorine
exceed the acceptable level (1). Therefore, it is necessary to calculate the health risk
control values of phosphorus and fluorine.
Table 5.33 Carcinogenicity
identification of focus
pollutants for the landfill in
Jiangxi Province
Focus pollutants
Carcinogenicity
Fluoride
No
Total phosphorus
No
5.1 Central China
145
leachate. Once the groundwater is contaminated, pollutants migrate, transform, and
spread through groundwater flows.
– Receptors
According to the landfill use and the surrounding population, groundwater pollutants will pose hazards to the exposed workers of the site and residents of the
surrounding areas, so workers inside the site are considered as in situ sensitive
receptors considered and residents around the site as off-site sensitive receptors.
• Exposure pathway analysis
Since the site contamination plume involves groundwater-based drinking water
sources, the exposure pathways for in situ receptors include indoor and outdoor
inhalation of vapor from groundwater and groundwater intake. For off-site receptors, there are four pathways of exposure: indoor inhalation of off-site vapor from
groundwater, outdoor inhalation of off-site vapor from groundwater, outdoor
inhalation of off-site vapor from groundwater, and groundwater intake (Fig. 5.13).
(d) Risk characterization
The risk characterization is based on the observed content of pollutants in the
groundwater. Human exposure parameters (mainly for adults) are selected in
China’s context and calculated separately with reference to the values for sensitive
and non-sensitive land recommended in the Technical Guidelines for Risk
Assessment of Contaminated Sites (HJ25.3–2014). The parameters include phosphorus and fluorine.
Using the HERA model for risk assessment, the hazard quotient through adult
exposure pathways is calculated, and the results are as shown in Table 5.35.
• Pollutant-specific results of hazard quotient
As shown in Table 5.35, the hazard quotient of both phosphorus and fluorine
exceed the acceptable level (1). Therefore, it is necessary to calculate the health risk
control values of phosphorus and fluorine.
Table 5.33 Carcinogenicity
identification of focus
pollutants for the landfill in
Jiangxi Province
Focus pollutants
Carcinogenicity
Fluoride
No
Total phosphorus
No
5.1 Central China
145