Human Health Risk Assessment of Heavy Metals from Bhalaswa Landfill, New Delhi, India - Management of Natural Resources in a Changing Environment - page 212

Table 1 Zoning of t he landfill area
Zones Radialdistance(inmetres) Pb maximum concentration (mg/L)

Zone I 0-2,520 m 0.053

Zone II 2,520-3,740 m 0.027

Zone III Beyond 3,740 m ND

Table 2 Risksforthezones

Carcinogenic risk

Non-carcinogenic risk
(HQ) Zones Lead acetate Lead sub-acetate Decision

Zone I 5.3 1.742 × 10 −4 2.364 × 10 −5 Risk

Zone II 2.7 8.874 × 10 −5 1.204 × 10 −5 Risk

Zone III NA NA NA NoRisk

HQ Hazard quotient, NA Not applicable

as shown in Table 1 . These risks are calculated for each stated zone as discussed for
Zone I above and are presented in Table 2 .

Risk Management and Communication

After completing the risk characterization process, various regulatory options need
to be evaluated in a process called risk management which includes consideration
of social, economic and political issues. One important step of risk management is
risk communication which is interactive process of information and opinion
exchange at personal, group and institutional level. Main focus should be transfer of
the valuable information from experts to non-experts i.e. local residents in the vicin-
ity of the landfill in a balanced nature. This would help in minimizing the impact of
the risk in an effective manner, thus completing the risk assessment study
successfully.

Limitations and Recommendations

This study is indicative, and there is a need to carry out a more detailed study, with
a larger number of samples being taken. There are currently no linings in the land-
ill.Itisamajorcauseforleachingofheavymetalsintothegroundwater.Stepshave
to be taken to ensure a clean water supply to the residents, and also to ensure that
thelandilldoesnotleadtofurthercontaminationofthegroundwater.Regularmon-
itoring of groundwater for heavy metals needs to be implemented.