HEAVY METAL
POLLUTION IN SOIL, GROUNDWATER AND SURFACE WATER OF SEVEN SELECTED LANDFILL
SITES OF KUALA LUMPUR
Md. Mizanur
Rahman1, Mohd. Nasir Hassan2, Puzia Abdul latif3, Mohd. Daud4, and Mohd.
Zohadie Bardaie5
1 Researcher, ESEIA Research
project, Faculty of Engineering
2,3 Faculty, Department of
Environmental Science
4,5 Faculty, Department of
Biological and Agricultural Engineering,
Universiti Putra Malaysia,
43400 UPM, Serdang,
Selangor, Malaysia.
1e-mail: mmr2660@hotmail.com
ABSTRACT
This
paper discusses the status of some selected heavy metals (Ni, Cu, Cr, Cd, Hg,
Se, Ag, As, Ba and Pb) of seven landfill sites in the Federal territory of
Kuala Lumpur, Malaysia. Except for one all the landfill site have been closed
for operation before 1990. None of the landfill site was covered with lined
material for prevention of leachate percolation to ground water and soil. Heavy metal concentrations have been
investigated for soil and ground water inside the landfill site and surface
water flowing along the site. The concentration of these pollutants
were then compared with the
relevant guidelines of the Department of Environment(DOE), Malaysia. The
results indicated that the extent of pollution of soil by heavy metals can be
considered low. In the case of
groundwater pollution, three sites namely Taman Beringin, Taman Rekaresi(TR)
and Jinjang Utara(JU) were found to be heavily polluted by Pb, Ba, Cu and
Cd. In the case of surface water, Taman
Beringin and Jinjang Utara sites were found to be heavily polluted by mercury
and cadmium.
Landfill leachates have been reported to contain a
wide range of heavy metals (Francies and Dodge, 1990). Composition of the solid
wastes disposed in a landfill determines the amount of heavy metals (Thayer,
1989) in the leachate and the composition varies with the sources of wastes
generation (Campbell, 1976; Alter, 1989) and with the composting process of the
landfill i.e. acidic or methanogenic phase. Soils and groundwater quality in
and around the landfill site is mainly affected due to infiltration or disposal
of leachates while surface water quality may be affected if untreated leachate
is discharged or due to leachate contaminated surface run-off into the nearby
water body (Christensen, 1992).
As for Malaysia, the information on common values of
heavy metals in soil is limited and therefore it is not possible to make an
accurate assessment on soil contamination. A study by Ramlan and Badri (1989)
reported that concentrations of heavy metals in soils and street dust contain
significantly higher amounts of Fe, Mn, Zn, Pb, Cu and Cd compared to the soil
underneath it. Major heavy metal pollutants in surface water in Malaysia
includes Hg, Cd, Cr, Cu, As, Zn and Se (DOE, 1997). DOE identifies industrial
and municipal wastes effluent discharges as the main reasons for high level of
trace metal pollution of water.
The objectives of the study was to examine the heavy
metal pollution in soil, groundwater and surface water due to landfill
activities and also to determine the critical sites based on the heavy
pollution level.
2.1
Operating Conditions of the
Landfill Sites
Both active and closed landfill sites were
considered for heavy metal analysis.
Landfills studies were Taman Beringin (TB), Taman Rekreasi (TR), Jinjang
Utara (JU), Sugei Besi (SB), Sri Petaling (SP), Kampung Paka 1 (KP1), and
Kampung Paka 2 (KP2). Unfortunately, information on the quantity and the type
of wastes being disposed at the
landfill sites selected was not available. Taman Beringin is the only active
landfill under consideration and it contains mainly household, commercial and
building construction wastes and also wastes from nearby light industries. Other landfills were situated in the sub-urban
part of Kuala Lumpur and was assumed to be filled with mainly municipal wastes.
Taman Beringin, Sungei Besi, Paka2 and Jinjang Utara landfill sites were
located in the ex-mining land.
2.2
Sampling Method
Three boreholes were drilled at each of the landfill
sites. Soil samples from each borehole were collected at two selected depths,
i.e. 1 meter above and below groundwater level. Plastic containers were used
for storing water samples for inorganic pollutants and major ions analysis. All
samples collected were stored in ice at 4oC during transportation to
the laboratory or until analysis were performed. Three samples were taken at
each sampling location.
Groundwater /leachate samples were collected from
three boreholes drilled at each of the landfill site selected for screening.
The collection of groundwater from the boreholes was conducted after the
groundwater has reached its original static water level. The groundwater or
leachate was collected after allowing at least one borehole volume have been
pumped out. Surface water samples were collected from the river located close
to the landfill sites. Standards procedures were followed for laboratory
analysis.
2.3
Evaluation of Heavy Metal
pollution
Assessment on the extent of heavy metal
contamination of soil and groundwater in and around the landfill sites was done
by comparing the detected concentration of the pollutants with the target and
intervention level concentrations suggested in the guidelines of soil /
groundwater quality criteria of the Malaysian EIA Guidelines for water Supply
(DOE, 1997). For assessing heavy metal
pollution of surface water, Interim Water Quality Standards (INQWS) (Pillay,
1993; DOE, 1997).
3.1.
Heavy Metal Pollutants
in Soil
Six metals were detected in the soil samples at
varying concentrations. They are nickel, chromium, cadmium, copper, silver and
lead. All the six metals were detected in the borehole soils of TB and TR
landfill sites. Four heavy metals, i.e. cadmium, copper, silver and lead were
detected in the borehole soils of JU and SP landfill sites. Three heavy metals,
i.e. copper, silver and lead were detected in the borehole soils of SB, KP1 and KP2 landfill sites. Table 2
shows the distribution of heavy metals found in the soil. Pollutant concentration
was measured in mg/kg.
Table 2. Distribution of Heavy Metal Concentrations
in the Soil Sample
|
LF/ HM |
Target Level |
TB |
JU |
TR |
SB |
KP1 |
KP2 |
SP |
Target exceeded by |
|
Ni |
35 |
23.1 |
0 |
72 |
0 |
0 |
0 |
0 |
|
|
Cu |
36 |
28.6 |
3.97 |
17.82 |
42.27 |
40.35 |
19.23 |
19.4 |
SB, KP1, |
|
Hg |
0.3 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
|
Cd |
0.8 |
3.32 |
3.97 |
7.28 |
0 |
0 |
0 |
4.13 |
TB, TR, JU, SP |
|
Se |
NA |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
|
Ag |
NA |
12.8 |
12.5 |
18.45 |
4.92 |
15.1 |
9.2 |
20.9 |
|
|
Cr |
100 |
39.23 |
0 |
133.6 |
0 |
0 |
0 |
0 |
TR |
|
Pb |
85 |
68.58 |
50.23 |
106.95 |
40.58 |
70.23 |
111.35 |
36.65 |
TR, KP2 |
|
Ba |
155 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
|
As |
29 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
Note: LF= Landfill sites, HM= Heavy Metals
Table 2 above shows that in general heavy metal
concentrations in the landfill soils were low except for cadmium and
silver. 4 out of 7 landfills were
heavily polluted by cadmium. Besides
all the landfills were also polluted by silver as the common range of silver in Malaysia is 0.1 to 8 mg/kg. Other
pollutants of concern were Cu, Cr, and Pb.
3.2.
Heavy Metals in the
Groundwater
The inorganic pollutants detected in the groundwater
samples from the boreholes and river
water sample are nickel, copper,
chromium, silver, cadmium, lead, barium, selenium, mercury and arsenic. Table 3
shows the distribution of heavy metals in the ground water surrounding the
sites.
Table 3: Heavy Metal Pollutants in Groundwater Samples (Concentrations in , Mg/L)
|
Landfills Pollutants |
Target
Value |
TB |
JU |
TR |
SB |
KP1 |
KP2 |
SP |
Landfills
exceeding the target level |
|
Ni |
0.015 |
0.03 |
0.075 |
0 |
0.014 |
0 |
0.007 |
0.043 |
TB, TR, SP |
|
Cu |
0.015 |
0.02 |
0.117 |
0.042 |
0 |
0 |
0 |
0.023 |
TB, JU, TR, SP |
|
Hg |
0.00005 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
|
Cd |
0.0004 |
0.004 |
0.069 |
1.824 |
0 |
0.074 |
0.001 |
0 |
TB, TR, JU, KP1, KP2 |
|
Se |
NA |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
|
Ag |
NA |
0.008 |
0.017 |
0.021 |
0.002 |
0 |
0 |
0.004 |
|
|
Cr |
0.001 |
0 |
0.019 |
0 |
0 |
0.004 |
0 |
0 |
KP1 |
|
Pb |
0.015 |
0.217 |
0.081 |
0.009 |
0 |
0 |
0.001 |
0 |
TB, JU |
|
Ba |
0.2 |
1.191 |
0 |
0 |
0 |
6.398 |
0 |
0 |
TB, KP1 |
|
As |
0.01 |
0 |
0.06 |
0.077 |
0 |
0 |
0 |
0 |
JU, TR |
Results shown in the Table 3 indicate that groundwater of Taman Beringin (TB) is
polluted by maximum number of
pollutants such as Ni, Cu, Cd, Pb, and Ba. And followed by TR, JU, KP1 and KP2
landfills. Out of 7 landfills, 5 were polluted by cadmium. Groundwater of SB landfill was found to be free from heavy
metal pollution. SP landfill was also not heavily polluted.
3.3
Distribution of Heavy Metal
in the Surface Water
The heavy metal pollutants detected in the surface
water samples from the river water sample were nickel, copper, chromium,
silver, cadmium, lead, barium, selenium, mercury and arsenic. Table5 shows the
distribution of heavy metals in the surface water surrounding the sites.
Table 4. Heavy Metal Pollutants in Surface Water Samples (concentration, mg/L)
|
LF/ HM |
Target Value |
TB |
JU |
KP1 |
KP2 |
SP |
Target exceeded by |
|
Ni |
0.015 |
0.12 |
0.075 |
0 |
0 |
0.007 |
TB, JU |
|
Cu |