UNIVERSITI PUTRA MALAYSIA

HEAVY METALS IN SURFACE SOILS OF KOTA BHARU LANDFILL

SITE AND ITS RELATIONS TO THE GROWTH AND MACRONUTRIENTS UPTAKE OF ACACIA MANGIUM

NIK MOHD. SHIBLI BIN NIK JAAFAR

FSAS 2004 4

CONTENTS

PageAbstract I Abstrak IV Acknowledgements VII Approval sheet VIII Declaration form X LIST OF TABLES XI LIST OF FIGURES XII LIST OF ABBREVIATIONS XIII

Chapter 1: Introduction 1.1 Importance of landfill practice 1 1.2 Landfills in Peninsula Malaysia 3 1.3 Problems in solid waste management in Malaysia 6 1.4 Incineration and recycling 9 1.5 Objectives of study 11

Chapter 2: Literature Review 2.1 Landfill definition 13 2.2 Landfilling methods 14 2.3 Landfill siting 18 2.4 Conceptual design of a landfill 20 2.5 Biodegradation processes in landfills 23 2.6 Heavy metals in landfills 26 2.7 Mechanisms of heavy metals toxicity 30 2.8 Plant responses to heavy metal toxicity 32 2.8.1 Heavy metals exclusion by root 33 2.8.2 Heavy metals detoxification and compartmentalization in plant 36 2.9 Acacia mangium for landfill reclamation and phytoremediation 38

Chapter 3: Methodology 3.1 Description of study site 41 3.2 Acacia mangium study plot 46 3.3 Sampling of surface soil, water samples and A. mangium leaves 47 3.4 Sample preparations for heavy metals analysis: acid digestion 49 3.5 Sequential extraction analysis of soil sample 50 3.6 Sample preparations for macronutrients (N,P and K) analysis 52 3.7 Heavy metal contents analysis 53 3.8 Analysis of macronutrients (N, P and K) in leaves samples 54 3.8.1 Indophenol blue: Analysis of total nitrogen 54 3.8.2 Molybdenum blue: Analysis of total phosphorus 55 3.8.3 Analysis of total potassium 56 3.9 Data analysis 57

Chapter 4: Result and discussion 4.1 Heavy metals (Fe, Cr, Zn, Cu Cd) in surface soil 59 4.2 Fractionation of heavy metals in landfill soil 67 4.3 Heavy metals in water samples 73 4.4 Heavy metal accumulation in A. mangium leaves 80 4.5 Macronutrients (N, P, K) uptake by A. mangium 85 4.6 Transfer of heavy metals from soil into A. mangium 89 4.7 Growth of A. mangium 93

Chapter 5: Conclusion 99 References 105 Appendix A 115 Appendix B 121 Author’s biodata 125 127

Abstract of thesis presented to the Senate of Universiti Putra Malaysia in fulfillment of the requirement for the degree of Master of Science

HEAVY METALS IN SURFACE SOILS OF KOTA BHARU LANDFILL SITE AND ITS RELATIONS TO THE GROWTH AND MACRONUTRIENTS UPTAKE

OF ACACIA MANGIUM

By

NIK MOHD. SHIBLI BIN NIK JAAFAR

March 2003

Chairman: Associate Professor Dr. Ahmad Bin Ismail Faculty: Science and Environmental Studies A study of heavy metals distribution in landfill surface soil, surface water and

landfill leachate and its relations to Acacia mangium growth and macronutrients

uptake was conducted in a landfill in Kota Bharu, Kelantan. Five heavy metals,

particularly Fe, Cr, Zn, Cu and Cd was analyzed in this study and results shows

elevated heavy metals concentration level compared to the control surface soil.

The distribution of the heavy metals in the surface soil from the landfill varies

throughout the study site. The concentration decreased prominently in the river

sediment adjacent to the landfill. The concentration of Fe was the highest that

ranged between 1993.4 – 2404.6μg/g, followed by Zn, 18.08 – 54.10 μg/g; Cr,

2.67 – 62.10 μg/g; Cu, 5.21 – 18.60 μg/g and Cd, 0.70 – 1.52 μg/g of soil dry

weight. However, compared to DOE soil threshold concentration, this landfill

was only slightly contaminated with Cd that exceeds the threshold with an

average of 0.94 μg/g. Heavy metals speciation by sequential extraction of

landfill surface soil shows that the surface soil was not yet contaminated with

heavy metals as the anthropogenic fraction is less than 30% of the total

concentration of heavy metals of the surface soil and mainly attached to the

organic matter. Concentration of heavy metals in landfill leachate shows higher

level than the surface water. However, the levels of heavy metals in both water

samples were still considered as low compared to other landfills due to dilution

by rain and river nearby. Cu concentrations in water samples were generally

higher than other heavy metals that ranged between 0.03 – 6.14 mg/L whereas

Cd and Cr were generally very low, below detectable limits. The level of

accumulation in A. mangium leaves was highest for Fe that ranged between

139.5 – 537.6 μg/g, followed by Cr 45.54 – 357.3 μg/g, Zn 29.36 - 57.23μg/g, Cu

6.88 - 15.61μg/g and Cd 1.63 - 3.48μg/g. However, Fe shows no significant

difference in the level of accumulation between landfill and control plants. Heavy

metals accumulation level in A. mangium leaves have very wide range

dependent on the leaves sampled. However, from the soil-plant concentration

ratio, heavy metals uptakes by A. mangium in landfill site were found higher than

control plants especially for Cr and Cd. Generally the concentration of heavy

metals was found so much higher in the plants tissues rather than in the landfill

surface soil and landfill leachate or surface water. Relation between heavy

metals accumulation in A. mangium and growth and macronutrient uptake was

not demonstrated this study as the N, P, K level in control and landfill site do not

show any significant correlation with heavy metals concentrations. Uptakes of N

and P in landfill A. mangium were found higher than control but on the contrary,

K was found higher in control plants. Growth of A.mangium in landfill was slightly

different with control plants as there are tendency of A. mangium in landfill site

to produce many branches, leaves and incisive increase of trunk diameter

whereas, control plants tends to gained heights very quick. This is due to

different soil type and climatic factors influence rather than heavy metals level in

the plants’ tissue. This study also proposed A. mangium is tolerant to Cd and Cr

however the use of A. mangium as general bioindicator for heavy metals was

not probable as only Cd and Cr was highly accumulated. A. mangium can be

used for phytoremediation of low contaminated soil as shown in his study.

Furthermore, landfill site is this study found it suitable to be used as A. mangium

culture site.

Abstrak tesis yang dikemukakan kepada Senat Universiti Putra Malaysia sebagai memenuhi keperluan untuk Ijazah Master Sains

KANDUNGAN LOGAM BERAT DIPERMUKAAN TANAH KAWASAN PELUPUSAN SAMPAH DI KOTA BHARU DAN KAITANNYA TERHADAP

PERTUMBUHAN SERTA KANDUNGAN MAKRONUTRIEN ACACIA MANGIUM

oleh

NIK MOHD. SHIBLI BIN NIK JAAFAR

Mac 2003

Pengerusi: Professor Madya Dr. Ahmad Bin Ismail Fakulti: Sains dan Pengajian Alam Sekitar

Kajian kandungan logam berat di permukaan tanah, air di permukaan dan air

dari sampah serta kaitannya terhadap pertumbuhan dan kandungan

makronutrien Acacia mangium telah di jalankan di tapak pelupusan sampah di

Kota Bharu, Kelantan. Lima logam berat yang dikaji iaitu Fe, Zn, Cr, Cu dan Cd

menunjukkan kandungan logam berat lebih tinggi di permukaan tanah di tapak

pelupusan sampah berbanding dalam tanah kawalan. Tahap kandungan logam

berat di permukaan tanah pelupusan sampah juga didapati sangat berbeza-

beza untuk setiap sampel dari seluruh kawasan kajian. Namun, kandungan

logam berat dalam sedimen sungai yang bersebelahan kawasan kajian ini

didapati lebih rendah dari permukaan tanah tapak pelupusan yang dikaji.

Kandungan Fe di permukaan tanah tapak pelupusan adalah yang tertinggi,

berjulat antara 1993.4 – 2404.4 μg/g diikuti oleh Zn;18.08 – 54.10 μg/g, Cr; 2.67

– 64.10 μg/g, Cu; 5.21 – 18.60 μg/g dan Cd; 0.70 – 1.52 μg/g berat kering

tanah. Walaubagaimanapun, secara umumnya tahap kandungan logam berat di

kawasan kajian adalah di bawah piawaian tahap kritikal tanah tercemar yang

digunapakai oleh Jabatan Alam Sekitar Malaysia. Hanya Cd didapati melebihi

aras tercemar dengan purata kandungan sebanyak 0.94 μg/g. Kandungan

logam berat yang diekstrak secara bersekuen dari permukaan tanah tapak

pelupusan sampah menunjukkan bahawa sekitar 30% sahaja logam berat

berpunca dari punca antropogenik dan kebanyakannya bergabung dengan

bahan organik. Sampel air dari sampah mempunyai kandungan logam berat

yang tinggi berbanding sampel air di permukaan tanah. Walaupun begitu,

kandungan ini boleh dianggap rendah berbanding sampel dari tapak pelupusan

lain kerana telah berlaku pencairan oleh air hujan dan sungai berdekatan.

Kepekatan Cu di dalam sampel air didapati tinggi berbanding logam berat yang

lain dengan julat antara 0.03 – 6.14 mg/L, manakala kepekatan Cd dan Cr

adalah amat rendah dan biasanya tidak dapat dikesan. Tahap pengumpulan

logam berat dalam daun A. mangium menunjukkan Fe yang tertinggi

kandungannya dengan julat antara 139.5 – 537.6 μg/g, diikuti oleh Cr; 45.54 –

357.3 μg/g, Zn; 29.36 – 57.23 μg/g, Cu; 6.88 – 15.61 μg/g, dan Cd 1.63 – 3.48

μg/g. Walaubagaimanapun, kandungan Fe tidak menunjukkan perbezaaan yang

bererti antara daun dari pokok yang ditanam di kawasan tapak pelupusan

sampah dan kawalan. Namun, hasil dari pengamatan nisbah kandungan logam

berat antara tanah dan daun A. mangium, pengambilan logam berat didapati

tinggi pada pokok yang ditanam di kawasan kawalan, terutamanya untuk logam

Cd dan Cr. Julat kandungan pengumpulan logam berat amat luas di dalam daun

A. mangium di mana kandungannya dipengaruhi oleh keadaan daun semasa

sampel diambil. Kandungan logam berat lebih tinggi dalam tisu tumbuhan

berbanding dari kandungannya dalam tanah dan air di persekitaran. Kaitan

antara logam berat dan kandungan makronutrien dalam daun dan pertumbuhan

A. mangium tidak kelihatan di mana tiada kaitan yang bererti dapat diperolehi

antara kandungan N, P, K dan kandungan logam berat. Namun begitu, secara

umumnya, kandungan N dan P di dalam daun A. mangium di kawasan

pelupusan sampah didapati lebih tinggi dari kawalan tetapi sebaliknya bagi K.

Pertumbuhan A. mangium di tapak pelupusan sampah berbeza sedikit dari

pertumbuhan pokok di tapak kawalan kerana dipengaruhi oleh faktor cuaca dan

jenis tanah yang berbeza bukannya akibat kandungan logam berat dalam yang

terkumpul dalam tisu. A.mangium di tapak pelupusan sampah lebih cenderung

mengeluarkan banyak daun dan dahan serta menambah diameter batang

manakala pokok di tapak kawalan lebih cepat menambah ketinggian. Hasil

kajian ini mencadangkan penggunaan A. mangium sebagai agen pemulihan

tanah yang sederhana tercemar tetapi penggunaan tumbuhan ini sebagai

penunjuk biologi umum adalah tidak sesuai kerana tumbuhan ini menimbun Cd

dan Cr yang terlalu tinggi. Tapak pelupusan sampah dari kajian ini sesuai

dijadikan kawasan penanaman pokok A. mangium.

ACKNOWLEDGEMENTS

The preparation of this thesis is a complex process that involves various

steps, beginning from planning, execution of the plan, data collection, data

analyses, writing reports and editing the thesis manuscript. In the process to

meet the requirements for the Master degree, a number of individuals have been

so helpful throughout the process and without their help this thesis would not be

realized. Supervisory committee chairman, Associate Professor Dr. Ahmad

Ismail, has played a major role throughout the process. His advice and support

has made the preparation of this thesis the most exciting experience a post-

graduate ever need. Members of the supervisory committee consist of Professor

Datuk Dr Nik Muhammad Nik Abd Majid, Associate Professor Dr. Mohd. Kamil

Yusoff and Dr. Muhammad Azani Alias have been so helpful in the preparation

of the thesis especially in term of moral support and financial aid. Nevertheless, I

also thanked my colleagues in the Ecology laboratory, Dr Yap Chee Kong, Ms.

Shahrizat, Wan Siti Fatimah, Syaizwan, Ferdaus, Jazlina and foremost, Siti Nor

Suriani. In addition, for those who have been helpful directly or indirectly in the

process, their help and support are duly acknowledged.

Approval

I certify that an Examination Committee met on 30st January 2004 to conduct the final examination of the Graduate Student on his Master of Science thesis entitled “Heavy metals in surface soils of landfill site and its relations to the growth of Acacia mangium and macronutrients uptake” in accordance with Universiti Pertanian Malaysia (Higher Degree) Act 1980 and Universiti Pertanian Malaysia (Higher Degree) Regulations 1981. The Committee recommends that the candidate be awarded the relevant degree. Members of the Examination Committee are as follows: Ahmad Bin Ismail, Ph.D. Associate Professor, Faculty Of Science and Environmental Studies, Universiti Putra Malaysia, (Chairman) Datuk Nik Muhamad Bin Nik Abd Majid, Ph.D. Professor, Faculty Of Forestry, Universiti Putra Malaysia (Member) Mohd. Kamil Bin Yusoff, Ph.D. Associate Professor, Faculty Of Science and Environmental Studies, Universiti Putra Malaysia (Member) Mohamad Azani Alias, Ph.D. Faculty Of Forestry, Universiti Putra Malaysia (Member) -------------------------------------------------------------

Professor Dr. Shamser Mohamad Ramadili Mohd. Deputy Dean of Graduate School,

Universiti Putra Malaysia Date:

This thesis submitted to the Senate of Universiti Putra Malaysia has been accepted as fulfillment of the requirement for the degree of Master of Science. --------------------------------- Professor Dr. Aini Ideris Dean of Graduate School Universiti Putra Malaysia

Date:

DECLARATION I hereby declare that the thesis is based on my original work except for quotations and citations that have been dully acknowledge. I also declare that it has not been previously or concurrently submitted for any other degree at UPM or other institutions. -------------------------------------------------- NIK MOHD. SHIBLI BIN NIK JAAFAR

Date: 1st April 2004

LIST OF TABLES

Title Page Table 1.1 Generation of waste in Kuala Lumpur in two decades 2 Table 1.2 Existing landfills condition in Peninsula Malaysia 4 Table 1.3 Present siting of landfills in Peninsula Malaysia 5 Table 1.4 Problems reported in landfill sites (%) 8 Table 1.6 Waste composition in Kuala Lumpur (in %) 10 Table 2.1 Siting limitation guidelines by the Department of

Environment adopted from USEPA. 19

Table 2.2 Configurations of landfill cover systems 22 Table 3 AAS instrument settings 53 Table 4.4 Comparison of heavy metals mean concentration in

surface soil and river sediment with threshold level guideline by DOE

66

Table 4.5 Heavy metal concentrations in leachate and surface water 76 Table 4.6 Correlation factors, r, between soil heavy metal

concentration and accumulation in A. mangium leaves. 89

Table 4.7 Heavy metals concentration ratio in soil and A. mangium leaves 91

Table 5 Mean concentration (ppm) of heavy metals in landfill soil (P1 to P10) and river sediment (S1 and S2). 121

Table 6 Mean concentration (ppm) of heavy metals in control soil 122

Table 7 Mean concentration (ppm) of heavy metals accumulation by Acacia mangium leaves 123

Table 8 Heavy metals threshold level specified by different country to indicate desirable maximum concentration in uncontaminated soil

124

LIST OF FIGURES

Title Page Figure 2.1 Trench method filling 17 Figure 2.2 Area method filling 17 Figure 2.3 Proposed degradation scheme for the organic fraction in

landfill 24

Figure 2.4 Schematic illustration of the redox potential, pH, and gas composition during different phases in a landfill

30

Figure 2.5 Heavy metals exclusion mechanism in roots 35 Figure 3.1 Map of study site in Kelantan 43 Figure 3.2 Lay out of landfill and water sampling points 44 Figure 4.1 Cd concentration in landfill surface soil 61 Figure 4.2 Cr concentration in landfill surface soil 61 Figure 4.3 Cu concentration in landfill surface soil 61 Figure 4.4 Zn concentration in landfill surface soil 61 Figure 4.5 Fe concentration in landfill surface soil 61 Figure 4.6 Zn concentration in control surface soil 62 Figure 4.7 Fe concentration in control surface soil 62 Figure 4.8 Cd concentration in control surface soil 62 Figure 4.9 Cr concentration in control surface soil 62 Figure 4.10 Cu concentration in control surface soil 62 Figure 4.11 Fractionation of Zn in four different fractions; (in %) from

the total concentration in landfill surface soil 72

Figure 4.12 Fractionation of Cu in four different fractions; (in%) from the total concentration in landfill surface soil

72

Figure 4.13 Fractionation of Cd in four different fractions; (in %) from the total concentration in landfill surface soil

72

Figure 4.14 Percentage difference between non-resistant and resistant fraction in landfill soil

72

Figure 4.15 Concentration of Cr in A. mangium leaves 83 Figure 4.16 Concentration of Cd in A. mangium leaves 83 Figure 4.17 Concentration of Cu in A. mangium leaves 83 Figure 4.18 Concentration of Fe in A. mangium leaves 83 Figure 4.19 Concentration of Zn in A. mangium leaves 83 Figure 4.20 N, P and K average content (in % per g dry weight) in A.

mangium leaves samples 87

Figure 4.21 Height increment of A. mangium for the period from December 2001 to April 2002.

98

Figure 4.22 Diameter increment of A. mangium for the period from December 2001 to April 2002.

98

Figure 5.1 Metal pile dumped in the landfill 115 Figure 5.2 Landfill cover used in this landfill consisting of sand and

gravel. 115

Figure 5.3 Waste spread in the landfill left without soil cover 116 Figure 5.4 Drain that has been dug through the study site flowing 116

into the river Figure 5.5 A. mangium planted in study plots with a distance of 3m

apart 117

Figure 5.6 River located beside the landfill and Sabak Beach 117 Figure 5.7 A. mangium grown in control site show a tendency to gain

high fast. 118

Figure 5.8 A. mangium grown in landfill site tends to produce more branches and leaves even have been trimmed several times.

118

Figure 5.9 Perkin Elmer AAnalyst 800 atomic absorption spectrophotometer

119

Figure 5.10 Jenway 8581 flame photometer 119 Figure 5.11 Shimadzu 160A UV spectrophotometer 120

LIST OF ABREVIATION

AAS Atomic Absorption Spectrophotometer ATP Adenosine Tri Phosphate DNA Deoxyribose Nucleic Acid DO Dissolved Oxygen DOE Department of Environment DOM Dissolved Organic Matters EFLE Easily, freely, leachable and exchangable EIA Environmental Impact Assessment MMS Malaysia Meteorological Services MT Metallothionein PC Phytochelatin ppm Part per million TOC Total Organic Contents TSS Total Suspended Solid USEPA United States Environmental Protection Agency UV Ultraviolet

CHAPTER 1

INTRODUCTION

1.1 Importance Of Landfill

Landfill is a land disposal of waste that has been practiced for centuries.

It is known that waste buried will eventually diminish thus enriching the soil with

the most wanted nutrients for plants. Until now, in rural area where no proper

waste collection services available, wastes are simply buried in a hole dug in the

garden or dumped in any open space nearby. However, if larger volumes of

wastes disposed in this manner, it has the potential to impose hazard to human

well-being. Solid waste disposal becomes a concern especially in urbanized

society, as waste produced daily cannot simply be buried in each own yard.

Solid wastes have to be collected and disposed in a designated area selected

for the purpose.

Malaysia nowadays has come so far to produce and consume so much in

this ever-growing economy. Better education, entertainment and employment

opportunities have also stimulated migration into urban areas, putting stress on

the infrastructure and municipal services including sewage disposal and solid

waste collection. In Kuala Lumpur, record shows that, the amount of waste

generated is increasing each year (Table 1.1) with an average of 1.5kg of waste

produced by each person. A total of more than 15,000 tonnes of waste are being

produced daily by Malaysian and disposed in all of the 230 official landfills,

which were already overflowing (Hassan et al., 1999).

Solid waste management is a major challenge for municipal and local

authorities, constituting more than 40% of their operating budgets. For example,

in 1998, Petaling Jaya Municipal Council spent RM1.8million a month for waste

management, 40% of its operating budget. With the increasing volume, solid

waste management merits urgent attention (Maseri, 2001).

Table 1.1: Generation of waste in Kuala Lumpur in two decades

Year Amount of waste generated

(Tonnes/day) 1980 700 1985 1350 1990 2000 1998 3510

Source: Hassan et al., 1999

1.2 Landfills In Peninsula Malaysia

By the end of 1970’s, solid waste management in Malaysia was still

primitive where municipal councils then could only managed to collect and

dumped all the waste in a designated land. There were virtually no sanitary

landfills ever existed in Malaysia and no respectable post-closure programs ever

made to handle the pollution arise from landfill (Nakamura, 1999). There were a

few documented reports on waste generation rates from urban and rural areas,

as studies concentrate on waste collection rates rather than waste generation

(Abdul et al., 1996). However, by mid 1990’s the public became more aware of

the ever-growing magnitude of solid waste generated and risks associated with

landfill. Hence, the government has implemented proper management programs

to cope with the problems including venturing into privatization of landfill

management.

From past records, the most common type of landfill was open dumping

(Table 1.2) where wastes were dumped in a deserted open space. Most of the

district councils in rural or sub urban areas with low population practiced open

dumping. Wastes are spread on a land without any preparation of the site before

landfilling and waste are seldom covered. Most of the landfill sites do not have

adequate facilities and equipment for managing or to operate the landfills, and

usually lack of supervision. These landfills are only able to support a minimal

volume of wastes and reclamation of these sites was almost impossible as it

takes a long period for the sites to stabilize. As for now this method was

accepted by the authority and the locals, where vacant land is always available

these dumpsites operate with minimal operating cost compared to others

methods.

Table 1.2: Existing landfills condition in Peninsula Malaysia

Methods Municipal councils District councils Count (%) Count (%)

Sanitary landfill 4 (33) 1 (2) Controlled tipping 4 (33) 19 (38.8)

Open dumping 3 (25) 29 (59.2) Dumping into water body 1 (9) 0 (0)

Number of data 12 sites 49 sites Source: Hassan et al., 1999

Sanitary landfills usually operate under privatization scheme and the

landfills located in urban areas This type has the most advanced landfill

technology with monitoring and post-closure programs have been designed

even before the landfill begins its operation. In developed countries this method

of landfills are also known as bioreactor where waste decomposition is

enhanced for faster stabilization of the site. This method needs big investment

for setting up the operation but in long term, it is still considered as low cost

practices due to fast site stabilization and minimum pollution problems arises.

Hence, closed landfills can be developed in short period.

Most landfills were located on a flat ground however, other landscapes

such as swamps, riversides, mountain areas and canyons that are not suitable

for development had been turned into landfills (Table 1.3). Location of landfills is

usually determined by political needs. Land with low economic value has the

highest priority to be converted into landfills. Nowadays, there are limitations for

allocating land as landfills with certain technical criteria plus acceptance by the

society has to be considered.

Table 1.3: Present siting of landfills in Peninsula Malaysia Municipal councils District councils River side 2 10 Swamp 5 8 Flat ground 1 19 Mountain area 3 9 Tin mine pool 2 3 Sea side 0 1 Others 1 3

Number of data 14 sites 53 sites Source: Hassan et al., 1999

1.3 Problems In Solid Waste Management In Malaysia

The problems of environmental pollution and disposal of solid and liquid

wastes are not new. Landfill sites, particularly those improperly managed have

numerous impacts to the environment. Activities such as uncontrolled disposal

of wastes, accidental spillage, use of herbicides and insecticides, and migration

of contaminants in the form of vapor, dust or leachate through the soil from

contaminated land into neighboring non-contaminated land contribute to

contamination of our ecosystems. The two most significant impacts are leachate

generation and the released of gas.

Landfill leachate is the main source of pollutants from landfills and affects

groundwater quality. A number of researches have indicated that the

groundwater is greatly affected by leachate. Among the contaminants that affect

our underground water quality is heavy metals. Elevated heavy metals levels

were observed in underground water receiving leachate from landfill sites (e.g.:

Loizodou and Kapetanios, 1983, Puziah, 1999a). Groundwater pollution is the

main concern of leachate effects since groundwater is our major sources of

water supply. From Table 1.4, it is clear that groundwater pollution by landfill

leachate is serious though moderately affecting the surface water.

Leachate has adverse effects on flora and fauna in the surrounding area.

It is known that diversity of shrubs and other ground cover plants is low in

landfills with high level of contamination and leachate production. Plant growth in

landfills is affected with the quality of leachate (Saberi, 1999). Leachate

contamination may result in high mortality rates of trees (Menser et al., 1983,

Wong and Leung, 1989).

Fauna diversity in landfills varies while active and after ceased operation.

In active landfills, fewer animals inhabit the site due to lack of vegetation. Landfill

operation will result in the destruction of existing vegetation and natural balance

between plants and animals within the habitat. Scavengers such as crows and

dogs dominate fauna species in landfills while insects mainly dominated by flies.

Closed landfills however attracted more animals. Animals inhabit the landfills are

usually infested with parasites and viruses and act as vectors for causing

disease to human (Jambari, 1999).

An additional problem that is significant to landfills is gas emission. Gases

such as methane (CH4), carbon dioxide (CO2), hydrogen sulfite (H2S) and other

type of greenhouse gases are the products of decomposition processes in

landfills. Landfill gas effected plant growth (Leone et al., 1983) but the main

concern of landfill gas emission is methane, which is highly flammable that

causes fire hazards in landfills (Abdullah and Awang, 1999). In countries like

United States and several others Europeans countries methane gas are

recovered from the landfills has become an economical assets of landfills as it is

used as fuel (Lisk, 1991). Landfills also have the potential to jeopardize human

health by the release of toxic chemical substances and inorganic contaminants

such as aromatic hydrocarbon and heavy metals that have carcinogenic effects

or poisoning due to decomposition of toxic containing wastes (Puziah, 1999b).

Table 1.4: Problems reported in landfill sites (%) Serious Not so serious No problem M D M D M D Ground water pollution

71.4 12 28.6 76 0 12

Leachate 57.2 7.2 42.8 78.5 0 14.3 Scavengers 50.0 8.6 37.5 74 12.5 17.4 Water pollution 37.5 12 50 72 12.5 16

Cover material 25 50 25 26.9 50 23.1

Littering 25 37.5 37.5 58.3 37.5 4.2 Open dumping 25 48 50 48 25 4.0

Odor 22.2 40 77.8 60 0 0 Fly 12.5 45.8 62.5 54.2 25 0 Air pollution 12.5 21.7 50 74 37.5 4.3 Crow 0 4.2 36.4 37.5 63.6 58.3 Noise 0 0 37.5 29.2 62.5 70.8 M= municipal councils: 9 councils D= district councils: 26 councils

Source: Hassan et al.,1999