uncontrol dumping waste.pdf

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Technical Committee on Geotechnics of Landfill EngineeringGerman Geotechnical Society (DGGT)

Technical Committee Sanitary LandfillsGerman Association for Water, Wastewater and Waste (DWA)

Association of Municipal Waste Management and City Cleaning (VKS in the VKU)

Working Group Landfill Technology

Toolkit Landfill Technology

Chapter 1.3

Health and Environmental Risks of Dumps and Landfills

Hans-Günter Ramke, Höxter, Germany

Reviewed by DGGT/DWA-VKS-Working Group

“Landfill Technology” and published in the internet

http://www.landfill-technology.info.

September 2007


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Chapter 1.3 Table of Contents

Table of ContentsPage

1 Introduction 1

2 Risks of Uncontrolled Dumping for Human Health 2

3 Complex of Problems with Waste Pickers on Landfills 3

4 Particular Emissions during Landfill Operation 4

5 Effects on Surface Water and Groundwater 6

6 Effects of Landfill Gas 8

7 Effects on Fauna and Flora 9

8 Emissions of Closed Landfills 11

9 Environmental Impact Assessment 12

10 Bibliography 13


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Chapter 1.3 1

1 Introduction

The objective of this chapter is to describe the most important health and environ-

mental risks which might be caused by disposal sites in order to illustrate the

necessity of adequate design, construction and operation of landfills. In each of thefollowing sections particular problems for human health and the different

environmental media, their causes, and mitigation measures are briefly explained.

Figure 1.1 shows the polluting emissions and other negative effects which must be

expected at uncontrolled dumps and poorly designed and/or operated landfills:

- leachate

- landfill gas

- surface runoff

- noise

- bad odour and smoke

- wind-blown litter and dust

- birds, vermin and insects.

Many negative effects such as noise, odour and smoke, wind-blown litter and dust or

accumulations of birds, vermin and insects can be minimised by appropriate landfill

operation, especially the runoff of contaminated surface water can be prevented

totally.

The most important emissions of dumps and landfills are leachate and landfill gas,

and even a closed (and restored) landfill will cause leachate and landfill gas for a

period of time.

Leachate and landfill gas generation cannot be avoided by landfilling of untreated

waste, but in opposite to an uncontrolled dump the environment can be protected

against pollution by liner systems, collection and treatment of emissions at a well

designed, constructed and operated landfill.

Figure 1.1:Schematic diagramof emissions ofdumps and landfills


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2 Environmental Risks

2 Risks of Uncontrolled Dumping for Human Health

Figure 2.1 describes the risks for human beings caused by uncontrolled dumping of

waste. Direct or indirect pathways for contaminants or negative effects from

uncontrolled disposal sites to human beings – especially for those living on or next tothe dumpsite – are

- the terrestrial food chain

- the aquatic food chain

- the chain of drinking water supply

- airborne emissions

- transfer of pathogens by biological vectors.

Many people living on or near dumps died during last years because of landslides of

waste bodies. These slides can destroy settlements some hundred metresdownwards the dumpsite.

A further serious problem is the co-disposal of municipal, hospital and industrial

waste, which is often practised in many countries. Particular hazards can be caused

e.g. by the following wastes:

- hospital wastes with pathogenic and infectious materials

- commercial wastes like used oil, batteries, and paints

- inorganic industrial wastes like acids, heavy metals, and asbestos

- organic industrial wastes like solvents, pesticides, pharmaceuticals.

Protection of human health means effective environmental protection, and adequate

waste disposal is one of its essential components.

Figure 2.1: Consequences of uncontrolled dumping of waste (OELTZSCHNER, 1996)


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Chapter 1.3 3

3 Complex of Problems with Waste Pickers on Landfi lls

One of the most serious problems in many countries all over the world is the practice,

that waste pickers and their families are living on dumpsites, picking recyclables out

of the waste without any protective equipment, and do not have any municipalinfrastructure (see Photo 3.1).

Photo 3.1:Waste pickers on a landfill inLatin America

Photo: P. Schnittger, Hamburg, Germany

The health hazards for waste pickers and their families are obvious:

- injuries or death caused by accidents with haulage trucks and compactors

- injuries caused by sharp waste components

- infections by direct ingestion of food waste

- infections caused by insects and rats

- poisoning by polluted water and gas.

Therefore waste picking should be prohibited, but it has to be considered, that

“recycling” is often the only source of income of the poor.

The whole problem can only be solved by a complex of measures like:

- permitting of waste picking

- improving of working conditions

- improving of living conditions “on site”.

Every local situation requires specific solutions and demands a close co-operation of

all the stakeholders in waste management.

The opening of a new landfill is a good opportunity to establish new rules and to offer

better working conditions for the waste pickers.


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4 Particular Emissions during Landfill Operation

Five types of emissions are typical for dumps and landfills during operation, because

they are partly caused by tipping and placement of waste:

- noise

- bad odour and smoke

- wind-blown litter and dust.

All of these emissions can be minimised by suitable landfill operation, while non-

organised dumping creates and increases the problems.

Noise is generated by the haulage trucks and the mobile equipment of the landfill like

compactors and bulldozers. The best measure to protect the neighbourhood against

noise is proper siting of a landfill. This includes access roads out of settlements as faras possible. Further measures of noise protection or reduction are bordering dams

around the tipping area and encased engine compartments.

The typical “bad odour” of landfills is a consequence of unavoidable biological

degradation processes. The in-situ biodegradation can only be reduced by pre-

treatment, but apart from these measures, which belong to a framework of modern

waste management, some simple measures can diminish bad odour emissions:

- no open dumping of sludges and other fast degradable wastes like wastes

from slaughter houses

- reduction of open tipping areas down to the necessary minimum space for

tipping and compaction

- collection and treatment of landfill gas parallel to the development of the

landfill body.

Further typical problems are fires – and the resulting smoke – on uncontrolled dumps

and sometimes on landfills (see Photo 4.1). Reasons for beginning of fires are

different:

- auto-ignition of non-compacted waste with high degrees of organics and

combustible materials

- waste-induced ignitions caused e.g. by hot ashes or chemically reacting

materials (like carbide)

- setting of fire to the wastes by the workers in order to minimise waste volume

or to destroy commercial waste like oil filters

- arson “just for fun” caused by people not belonging to the landfill.

Auto-ignition of waste and waste induced ignitions often cause “hidden” fires which

smoulder inside the waste body. Also burning waste heaps at the top or the edges of

a dumping area can turn into a smouldering fire inside the waste body.


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Chapter 1.3 5

Photo 4.1:Burning dump in theMiddle East

Photo: H.-G. Ramke, Braunschweig, Germany

These fires are difficult to extinguish and often they gleam for many months. Under

unfavourable conditions a fire can get out of control and ignite the whole dumpsite.

Next to the uncontrolled release of toxic gases burning waste generates a lot of

smoke. Smoke of burning waste is sometimes a dominant factor of the atmospheric

load with particulate matters in cities of developing countries.

Self-ignition of waste can be reduced by waste compaction, which is decreasing the

air supply inside the waste body. This also prevents the turn of open fires into

smouldering fires. Intentional waste fires can be stopped by good landfill practice and

site control.

Wind-blown litter consists of paper and plastic sheets. These sheets can affect the

neighbourhood of a landfill in a range up to some hundred metres. The sheets are

blown both during unloading of haulage trucks and from the surface of the tipping

area. Dust becomes a problem when municipal waste contains a lot of ashes and if

waste is covered with soil which desiccates in dry periods.

The problem of wind-blown litter and dust during unloading can be reduced by

preparation of tipping areas sheltered from the wind (not at the top of the landfill,

construction of higher bordering dams). Compaction of waste significantly reduces

blowing of paper and plastic sheets, and in addition paper catching fences or

hedgerows are useful. Sprinkling of earth covers and sandy roads prevents dust

emissions.


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5 Effects on Surface Water and Groundwater

The effects of polluted surface run-off and leachate on surface water and

groundwater are the most serious pollution in the mid- and long-term perspective

brought about by dumps and landfills.

Dumping of waste in the neighbourhood of surface waters like creeks, rivers, and

lakes without any protective measures must result in water pollution caused by

surface run-off from the dumping area. The type of pollution depends on the types of

waste disposed of. The contaminants can range from oil, toxic inorganic and organic

chemicals, and pathogenic germs to inorganic salts and organic constituents washed

out of the wastes disposed of. Toxic substances, salts and organic pollutants can

interfere with the aquatic fauna seriously and spoil the surface water for human

purposes.

Volume or height of surface run-off from disposal areas is determined by:

- intensity of rainfalls

- geometry of the site

- properties of soils and wastes.

Surface run-off can become a problem especially in countries with very high annual

rainfalls or in arid countries with very intensive rainfalls in a few weeks of the year.

Protective measures against pollution by surface run-off from waste disposal areas

are simply to realise:

- clear definition of disposal areas

- bottom and bordering dams around the disposal areas

- ditches around the disposal areas for surface run-off collection.

These measures represent good landfill practice and will reliably prevent pollution by

surface run-off.

Leachate is generated when precipitation seeps into a landfill body. The water

percolates the waste and solutes inorganic and organic waste compounds. Leachate

from landfills for municipal waste is often 10 – 100 times higher loaded with organic

compounds than municipal sewage. In addition to the organic constituents, which are

often easily degradable, leachate contains ammonia in high concentrations, which is

toxic for fishes. Furthermore many other contaminants are found in leachate from

dumpsites and landfills, due to the types of waste disposed of.

Photo 5.1 shows an unsealed leachate pond at the foot of a dumpsite in the Middle

East. The pond with a surface of some hectares does not disappear despite high

evaporation rates and the missing bottom liner. The neighbourhood suffers from the

bad odour emitted from this pond.


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Chapter 1.3 7

Photo 5.1:Uncontrolled leachate pond atthe foot of a dumpsite in theMiddle East

Photo: H.-G. Ramke, Braunschweig, Germany

Photo 5.2:Pollution of surface- andgroundwater by leachate froman uncontrolled dump inLatin America


Photo 5.2 demonstrates surface- and groundwater pollution directly at the foot of an

uncontrolled dump.

The height of leachate generation is determined by climatic conditions and waste

characteristics. In Central Europe climatic conditions determine the height of

leachate, in developing countries with arid climates very often leachate is dominantly

generated by consolidation processes (squeezing out of water from wet waste).

Groundwater pollution prevention is the main task of design and construction of

landfills, in opposite to non-sealed dumps. Landfills have to have a bottom liner, a

leachate collection system, and a leachate management.


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6 Effects of Landfi ll Gas

Anaerobic degradation of organic materials in landfills produces biogas, called landfill

gas. Landfill gas mainly consists of methane and carbon dioxide, and in addition a lot

of trace gases are included.

Landfill gas generation rates depend on the amount of waste disposed of, the content

of organics, and abiotic conditions like moisture and temperature. Approximately

200 l/kg municipal waste can be produced within a period of 20 years. Fresh waste

generates more landfill gas than older materials.

Methane is inflammable and explosive in air in a range of concentration of 5 % (lower

explosion limit) to 15 % (upper explosion limit). Carbon dioxide affects the respiratory

centre of human beings, and even if oxygen concentration is sufficient, more than

5 % of carbon dioxide in air lead to headache and vertigo, more than 8 % are lethal.Many trace gases are extremely odour intensive (like mercaptans), others are toxic

(like hydrogen sulphur) or carcinogenic (e.g. chlorinated hydrocarbons).

On site the main risk caused by landfill gas is the risk of explosions when landfill gas

and air are in an explosive mixture. Furthermore fires, especially at the outlet of drain

pipes or gas wells and at cracks in cover layers, can flare back into the waste and set

the landfill body into fire.

In the surrounding areas problems are caused by landfill gas, if the gas migrates in

soil layers of high conductivity or in trenches backfilled with coarse material. The

horizontal emission in the subsoil can accumulate landfill gas below neighboured

residential and commercial buildings, especially in cellars. When methane

concentration exceeds the lower explosion limit in those rooms one spark – e.g. by

switching on lights – will let the buildings explode.

Finally a lingering poisoning of landfill workers and residents in the neighbourhood

cannot be excluded if landfill gas contains a lot of toxic compounds, especially on

landfills with high amounts of industrial waste in conjunction with biodegradable

putrescibles.

Apart from damages from landfill gas the influence of methane on the greenhouse

effect should be considered. The effect of methane on the global warming is fifty

times higher than the effect of carbon dioxide.

After landfill restoration non-collected landfill gas migrates through the restoration

layer and displaces soil air. This damages the plants due to the missing oxygen in the

root zone.

Most of the effects described above can be coped by engineering methods like

installation of liners after closure of landfills, gas collection, and gas treatment as

early as possible after beginning waste dumping.


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Chapter 1.3 9

7 Effects on Fauna and Flora

Dumps and landfills influence both the fauna and flora on the site and in its

neighbourhood.

Especially the rapid development of vermin and birds on landfills is a serious

problem, because insects, rats and birds are vectors of diseases.

Three examples shall demonstrate the effects on the fauna on the site.

Birds on Landfills all over the World

Landfills are very attractive for many types of birds all over the world. Especially

omnivores like seagulls and scavengers like some types of crows find a lot of food in

newly tipped wastes (see Photo 7.1).

Typical are colonies of one or two species, which dominate the landfill in huge and

dense flocks. The unloading haulage trucks are surrounded by excited birds, and the

whole surface of non compacted or non covered waste is overcast with them.

In addition to omnivores in Germany rare raptors could be found on landfills. Again

the broad offer of food ensures the surviving of this endangered species.

Overpopulation of birds on landfills can be controlled by adequate landfill operation

(small tipping areas, compaction, and earth cover) and by hunting.

Rats and Snakes on a Control led Dump in the Middle East

The particular dumpsite was placed in a semi-desert area; the distance to residential

zones was about 30 km. The waste, which typically contained a lot of organics, was

not compacted, just spread with a bulldozer.

The high content of food waste attracted small mammals, especially rats, living in the

semi-desert. Optimal living conditions resulted in a rapid development of rats’

quantity, and landfill workers and waste pickers, living on the landfill, were affected bythese aggressive rodents.

As a consequence of this abnormal rat population in the semi-desert snakes

discovered the dumpsite as habitat, and once again due to the optimal living

conditions a normally small population increased rapidly.

This huge risk for health and life of the landfill workers and waste pickers living on the

site required urgent measures. A compactor was bought, and after compacting the

waste both the rat population and the snake population totally broke down.


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Photo 7.1:Flock of birds on a dump inLatin America


Cockroaches on a Landfill in Germany

A specific example for rapid development of a population of insects was observed at

a landfill in Germany. At the end of the seventies first experience was made in

Germany with mechanical-biological pre-treatment. On one of the landfills operated

as “rotting landfill” with aerobic biological decomposition of waste in windrows before

compacting an explosion of the population of cockroaches occurred.

The cockroaches were released from a wood processing factory, which delivered

weekly wood shavings to the municipal landfill. All of the deliveries of wood shavings

contained some cockroaches, which normally would not have created problems on a

normally operated landfill. The windrows on the other hand guaranteed all the abiotic

factors for a perfect environment for the cockroaches: shelters, warmth, good oxygen

supply, and a lot of organic food. The result was an extremely fast development of a

population of cockroaches with millions of specimens.

The population broke down – like the populations of rats and snakes in Jordan –

again after compacting the windrows. This special case shows, that rotting landfillsare easily to protect against vermin by compacting the windrows after an intensive

attack of insects. In addition the rotting technique was improved, and one of the

reasons for covering the rotting windrows with pre-treated material is the protection

against vermin (less food, worse living conditions).

These three examples demonstrate the necessity of good landfill operation to prevent

infestations with vermin and birds. Quickly covering of easily biodegradable wastes

like sludge and food waste, compaction of all wastes and small tipping areas will

reduce the problems.


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Chapter 1.3 11

The effects on the flora are of less importance. At first damages of plants could be

caused by landfill gas, even in the surrounding of dump sites. Landfill gas collection

and liners can mitigate most of these damages.

A further risk is farming on uncontrolled or abandoned dumps. This may lead to anuptake of contaminants by the plants. Organisational measures can prevent people

from ingestion of polluted food.

8 Emissions after Landfil l Closure

The environmental impacts caused by landfill operation like traffic noise and tipping

related litter and dust have ceased after the end of landfill operation, but a dumpsite,

which is not restored, is still an open wound in the landscape.

Furthermore dumps and landfills are long-term sources of emissions:

- precipitation and consolidation processes produce leachate

- ongoing degradation processes generating landfill gas.

Every disposal site – a dump as well as a landfill – has to be covered at least with an

earth layer to mitigate most of the direct problems caused by a heap of open waste:

- to prevent direct contact of human beings to waste

- to prevent direct contact of livestock to waste- to prevent spreading of litter and dust

- to integrate the dumpsite into the landscape.

The characteristics of the site, the properties of wastes disposed of, and the

sensitivity of the environment define the quality of the cover of the dumpsite:

- At minimum a cover with soil is necessary, too, to prevent pollution of surface

run-off, to reduce leachate generation, and to improve gas collection.

- A full surface capping system might become indispensable if the effectiverainfall is quite high, and leachate generation has to be minimised.

Last but not least a landfill needs aftercare:

- emission treatment plants must be operated for a limited period

- walk-over controls are important to ensure suitable land use

- especially groundwater needs regular monitoring.

Finally the dumpsite has to be registered to ensure the knowledge about its existence

for the future.


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9 Environmental Impact Assessment

Despite the fact, that every disposal site - and in particular an uncontrolled dump –

has environmental impacts, a landfill can be designed, constructed and operated in

such a way that negative impacts on the environment are reduced to a minimum.

Therefore Environmental Impact Assessments (EIAs) are an integrated part of all

phases of landfill design. Their objective is to develop the solution with environmental

disadvantages as little as possible in the frame of the local conditions.

Most of the important direct impacts of dumpsites were mentioned in the previous

sections, and some mitigation measures were touched. In addition indirect impacts

like land use conflicts and visible degradation of the urban environment are to be

considered in an EIA.

The EIA should be performed in two stages:

- Stage 1: Site selection

In the course of selection of a suitable site for a landfill an accompanying EIA

is the most appropriate instrument to compare the ecological sensitivity and

the consequences of project related impacts at different sites.

- Stage 2: Landfill design

During the phase of landfill design the EIA is a valuable tool to adapt the

basic design, the barrier systems, and emission treatment plants to the

specific situation of the site selected.

It should be an objective for every party involved in landfill planning to integrate

design and environmental impact assessment as close as possible. The development

of mitigation measures should be understood as a common activity of the design

team and the EIA team.

The EIA has to cover the construction phase, the operation phase, and the post-

closure phase of a landfill. Main topics of an EIA are:

- description of the project

- description the environment

- description of potential impacts of the project

- comparison of alternatives (including the “to-do-nothing-alternative”)

- development of mitigation measures.

A detailed overview of potential negative impacts and mitigation measures is given by

the Sectoral Guidelines of the Environmental Assessment Sourcebook of the WORLD

B ANK, 1991. Chapter 2.1 explains how to integrate the EIA-approach into the tasks of

the phase of site selection.


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Chapter 1.3 13

10 Bibliography

OELTZSCHNER, H.; MUTZ, D., 1996: Guidelines for an Appropriate Management of SanitaryLandfill SitesDivision Water, Waste Management and Protection of Natural ResourcesDeutsche Gesellschaft für Technische Zusammenarbeit (GTZ), Eschborn,Germany

WORLD B ANK, 1991: Environmental Sourcebook, Volume II – Sectoral GuidelinesWorld Bank Technical Paper Number 140The World Bank, Washington, D.C., USAInternet-Download, dated 02.08.2006

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