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Waste Manage Res 2007: 25: 234–240
Setting priorities for waste management strategies
in developing countries
This study aimed to determine whether the waste management
systems, that are presently applied in affluent countries
are appropriate solutions for waste management in less developed
regions. For this purpose, three cities (Vienna, Damascus
and Dhaka) which differ greatly in their gross domestic
product and waste management were compared. The criteria
for evaluation were economic parameters, and indicators as
to whether the goals of waste management (protection of
human health and the environment, the conservation of
resources) were reached. Based on case studies, it was found
that for regions spending 1–10 € capita–1 year–1 for waste
management, the ‘waste hierarchy’ of prevention, recycling
and disposal is not an appropriate strategy. In such regions,
the improvement of disposal systems (complete collection,
upgrading to sanitary landfilling) is the most cost-effective
method to reach the objectives of solid waste management.
Concepts that are widely applied in developed countries such
as incineration and mechanical waste treatment are not suitable
methods to reach waste management goals in countries
where people cannot spend more than 10 € per person for the
collection, treatment and disposal of their waste. It is recommended
that each region first determines its economic capacity
for waste management and then designs its waste management
system according to this capacity and the goals of waste
management.
Paul H. Brunner
Johann Fellner
Vienna University of Technology, Institute for Water Quality,
Resources and Waste Management, Vienna, Austria
Keywords: Developing countries, waste management strategies,
economic conditions, goal oriented evaluation, wmr 1165–9
Corresponding author: Johann Fellner, Vienna University of
Technology; Institute for Water Quality, Resources and Waste
Management, Karlsplatz 13/E226, A-1040 Vienna, Austria
Tel: +43 1 58801 22654; fax: +43 1 5042234;
e-mail: [email protected]
DOI: 10.1177/0734242X07078296
Received 12 January 2007; accepted in revised form 12 February 2007
Introduction
The main aims of waste management are: (1) to protect
human beings and the environment; and (2) to conserve
resources. Under the principles of sustainability, these goals,
which apply world-wide for any economy, should be achieved
in a way that does not impair the wellbeing of current as well
as future generations. Thus, waste management practice should
not export waste-related problems in space or in time, requiring,
for example, appropriate treatment capacities and aftercarefree landfills.
The first of these aims has been achieved in most countries
with affluent economies that can afford ∼100 € capita–1 year–1
for waste management. Hence these countries focus on aim
number two, introducing extended recycling strategies and
schemes. On the other hand, in developing countries which
spend 1–10 € capita–1 year–1, the health and wellbeing of people
still suffers due to inadequate waste management practice,
and thus protection of human health is still the number
one objective.
Conclusions
The main objectives of solid waste management are to protect
human health and the environment, and to conserve
resources. In affluent countries direct impacts of wastes on
humans and the environment have been eliminated; hence,
these countries focus on resources by introducing extended
recycling strategies and expensive pre-treatment technologies.
In countries with a low GDP (e.g. Syria and Bangladesh)
current practices of solid waste management still do
not meet the primary objective of protection of human
health. Thus, MSWM in these regions must focus on different
issues to those that apply in affluent countries. Most
important is the introduction of a complete collection service,
since this is the most effective way to protect human
health. In case of sufficient (internal) financial resources for
MSWM, this key measure is to be supplemented by upgrading
the current disposal practice to sanitary landfilling. This
measure will cost-effectively reduce environmental impacts.
The other measures investigated were either too expensive
(e.g. biological or thermal waste treatment), difficult to
implement or hard to accept by local stakeholders (e.g. separate
waste collection would cut the income of thousands of
scavengers). Before emphasis is placed on reaching the goal
of resources conservation, the main objective of waste management,
that is to protect human health and the environment,
must be fulfilled.
Resources, Conservation and Recycling 39 (2003) 193_/210
Garbage, work and society
Hector Castillo Berthier *
UNAM Institute for Social Research, Circuito Mario de la Cueva s/n, Ciudad de las Humanidades, Ciudad
Universitaria, C.P. 04510 Mexico, D.F., Mexico
Containment landfills: the myth of sustainability
A. Allen*
Department of Geology, University College Cork, Cork, Ireland
Engineering Geology 60 (2001) 3±19
www.elsevier.nl/locate/enggeo
Garbage, work and society
Hector Castillo Berthier *
UNAM Institute for Social Research, Circuito Mario de la Cueva s/n, Ciudad de las Humanidades, Ciudad
Universitaria, C.P. 04510 Mexico, D.F., Mexico
Received 1 June 2002; accepted 1 September 2002
Abstract
This paper reviews the contribution of the book ‘The Garbage Society: Caciquismo in
Mexico City’; written 20 years ago when no official statistics on garbage production were
available, to the development of sustainable waste management practice in Mexico. At that
time public information was extremely difficult to obtain and environmental pollution was not
regarded as an important research area for many disciplines, including social sciences. The
objective of ‘The Garbage Society’ was to provide a detailed description of all the stages
involved in garbage disposal from the time when it is discarded, until it resurfaces in recycled
products. This process can be summarized as Garbage_/Working force_/Merchandise. The
garbage problem in Mexico City is an accurate reflection of the Mexican political system that
has traditionally supported corporatism in which caciques (a person who exercises absolute
power over a group) play a key role. Current data are used to verify the events of that first
study and through reflection on the historical process, to indicate the requirements for ongoing
research as a means of clarifying and categorizing the inherent problems associated with
sustainable waste management in Mexico.
2003 Elsevier Science B.V. All rights reserved.
* Tel.: _/52-5-5622-7400x302; fax: _/52-5-5665-2443.
E-mail address: [email protected] (H. Castillo Berthier).
Resources, Conservation and Recycling 39 (2003) 193_/210
www.elsevier.com/locate/resconrec
0921-3449/03/$ - see front matter # 2003 Elsevier Science B.V. All rights reserved.
doi:10.1016/S0921-3449(03)00027-2
Keywords: Garbage; Society; Recycling; Solid waste; Participatory research; Marginalization
1. Introduction
Garbage workers throughout the world have different names: packs and teugs (the
latter belonging to an inferior social breed) in Dakar (Communaute´ Urbaine de
Dakar, 1986), wahis and zabbaleen in Cairo (Neamatalla, 1981), gallinazos in
Colombia (Birkbeck, 1978), chamberos in Ecuador, buzos in Costa Rica, cirujas in
Argentina, catadores in Brazil, scavengers or garbage pickers in English speaking
countries and pepenadores or resoqueadores in Mexico.
Studies on the recovery and recycling of materials taken from garbage have been
carried out for several decades now. One of the most important early studies,
concerning an industrial zone in Akron, Ohio, briefly analyzed the materials
recovered, the public collection system, the use of convicts as a work force for the
selection of materials and the commercialization of these products (Baldensparger,
1919). In addition, ‘The Manual of the Community’s Recycling Programs’ (Hoy and
Robinson, 1979), traces the history of garbage recycling in the United States from
1840 to 1945. This work includes an analysis of the New York system under the
direction of George Waring. In early 1890, Waring created a program for waste
recovery, street cleaning and public health improvement, which reduced administrative
costs for solid waste management. This program was subsequently
implemented in other American cities.
During the first half of the 20th century, several isolated studies were conducted
on this issue. It was not until the end of the 1950s, however, that waste management
and public sanitation was seriously addressed in developing countries. Studies and
reports submitted by a number of specialists (Gotaas, 1956; Andrews, 1957; TIES,
1959) attest to this but, in fact, the real acceptance of the studies concerning the
problems derived from garbage began in the early 1970s, with attention given to the
situation of non-industrialized countries like Thailand, Sri Lanka, Senegal, Egypt,
Taiwan, Peru, China and Colombia etc (World Bank, 1984).
In the case of developed countries, waste management or garbage studies tended
to focus on technological development, involving either the collection, transport and
eventual disposal of these waste materials, or their recovery, processing and
industrialization. In cities where scavengers or garbage pickers were found, the
general recommendation was to ‘exclude them from the recovery processes’ (SCS,
1974) so that the system could be as mechanized as possible. Despite having the
approval of the United Nations, this recommendation should be reconsidered when
analyzing the cases of Third World countries. There, situations range from the total
mechanization of systems to the extensive use of labour in city dumps, all of which
are directed towards reusing the waste of modern society. Not all the studies,
however, refer exclusively to ‘technological advances’. Studies on Third World
countries tend to focus on scavengers’ or garbage pickers’ modes of organization,
their type of work, living conditions, income and the social and political interaction
they engage in with other groups.
The analytical sections of these studies often contain references to the ‘informal
sector’, ‘marginality’, ‘job independence’ or ‘low productivity’ in the manual
recovery of discarded products, as well as the economy’s ‘duality’ with its consequent
‘social exclusion’. As a result, their proposals are more oriented towards proposing
the modernization of these systems, which incidentally promotes the sale of the
technology produced in the First World, incinerators, compost plants, metal
foundries, sanitary fills etc.
H. Castillo Berthier / Resources, Conservation and Recycling 39 (2003) 193_/210 194
Thus, on the one hand, there has been technological progress in garbage
management that seeks to achieve clean cities, with maximum reuse of waste
products and community ecological awareness. On the other hand, the Third World
with its huge city dumps, has hundreds of thousands of people making a living from
waste, thereby polluting the environment and creating more poverty and marginalization.
Moreover, the land available for managing and storing waste is reduced,
while the problem of waste management is pushed into the background due to the
recurrent economic crises in these countries.
Despite this, a Manichean reductionism that regards the First World as a place of
‘technological marvels’ and underdeveloped countries as being on ‘the edges of
civilization’, would be false. Not everything is right about the former or wrong about
the latter. It is useful not to view technology as a miraculous panacea that solves
problems such as this. One has to consider the multiplicity of social relationships
that take place between the various human groups participating in the same activity.
In order to illustrate the complexity of the social relationships involved in solid
waste management and disposal in a Third World country, the case ofMexico City is
described below.
2. A social perspective
Perhaps all societies can be evaluated through a study of their management of
waste. This is particularly true of the large, heterogeneous community living in
Mexico City, since the perennial problem of garbage constitutes an accurate
reflection of the traditional Mexican political system. Thus, the visible functionality
of solid waste management conceals complicated relationships of power groups for
which the garbage has been and still is an enormous political and economic booty.
These have posed a serious threat to the development of long-term strategies in the
area of solid waste management but, paradoxically, each group is crucial to ensuring
that ‘everything functions efficiently and the city is kept clean’.
The first systematic study on the social problem of garbage in Mexico was
published in 1983. At that time, there were no official statistics on the subject, no
sources of public information, the environment was neither a fashionable nor a
serious problem and, generally speaking, environmental pollution was not considered
a viable area of research within the social sciences.
This study, ‘Garbage Society: Caciquism in Mexico City’ (Castillo Berthier, 1983),
provides a detailed description of all the steps involved in garbage disposal, from its
being discarded by the public, to, after many steps, when we acquire it again in the
form of new products.
The lack of available information for undertaking this project required the author
participating via direct involvement in the system; first as a temporary borough
street sweeper and then as a garbage collector and eventually obtaining scavengers’
access to the legendary Santa Cruz Meyehualco city dump. This ‘little town’ of
scavengers that at that time housed over ten thousand garbage pickers (including
H. Castillo Berthier / Resources, Conservation and Recycling 39 (2003) 193_/210 195
men, women, children, and the elderly) covered an area of more than 165 hectares.
Until its closure in 1984, it handled the city’s garbage for over 22 years.
As a result of this participatory research,or participant observation as it is known
in Anthropology, and the information obtained first hand, the main statements
gathered in that first investigation have since served as essential references for the
development of further studies related to the subject of garbage. A brief summary of
the main ideas and conclusions obtained is given below to provide a general overview
of the problem and to gauge the progress achieved since this initial study.
It is possible to begin by saying that waste is worthless. When it is discarded many
consider it worth nothing, but from the moment it is collected, transported, stored,
classified, cleaned, sold and recycled/reused, it is transformed into merchandise. This
means its inherent value and initial exchange value can be recovered if human labour
is incorporated. This can be expressed in the following formula: Garbage_
/
Labour_ Merchandise, which although apparently simplistic, implies a long,
/
complex process of economic circulation.
In this respect, waste is the link that allows the Merchandise Cycle to close:
In Mexican society, garbage is regarded as something that has already lost its use
and exchange value, something that is useless and that society has to get rid of. This
way of thinking about what garbage means has hampered society’s ability to see it in
different ways and to determine its real meaning and value in our lives. To begin
with, if it is true that different products and goods are transformed into garbage
when they lose their utility for us as consumers, then it is also true that, from the
start of its collection and recycling these former consumer goods gradually acquire
new value through these activities.
Nevertheless, this new ‘merchandise’ is permeated by a complicated web of social
relationships that largely define its future use and eventual forms of disposal. To
begin with, Article 10 of the Current Regulations for the Federal District’s Cleaning
Service states that: ‘The collection of domiciliary solid waste will be free’. Although
subsequent reference is made to certain forms of regulation of merchandising
establishments, this fact has contributed to a series of interpretations that have made
waste collection ‘free’ by law but ‘expensive’ in fact.
Containment landfills: the myth of sustainability
A. Allen*
Department of Geology, University College Cork, Cork, Ireland
Engineering Geology 60 (2001) 3±19
www.elsevier.nl/locate/enggeo
Abstract
A number of major problems associated with the containment approach to landfill
management are highlighted. The fundamental ¯aw in the strategy is that dry entombment
of waste inhibits its degradation, so prolonging the activity of the waste and delaying,
possibly for several decades, its stabilisation to an inert state. This, coupled with
uncertainties as to the long-term durability of synthetic lining systems, increases the
potential, for liner failure at some stage in the future whilst the waste is still active, leading
to groundwater pollution by landfill leachate. Clay liners also pose problems as the smectite
components of bentonite liners are subject to chemical interaction with landfill leachate,
leading to a reduction in their swelling capacity and increase in hydraulic conductivity.
Thus, their ability to perform a containment role diminishes with time. More critically, if
diffusion rather than advection is the dominant contaminant migration mechanism, then no
liner will be completely imperme¬able to pollutants and the containment strategy becomes
untenable.
There are other less obvious problems with the containment strategy. One is the tendency to
place total reliance on artificial lining systems and pay little attention to local
geological/hydrogeological conditions during selection of landfill sites. Based on the attitude
that any site can be engineered for landfilling and that complete protection of groundwater
can be effected by lining systems, negative geological characteristics of sites are being
ignored. Furthermore, excessive costs in construction and operation of containment
landfills necessitate that they are large scale operations (superdumps), with associated
transfer facilities and transport costs, all of which add to overall waste management costs.
Taken together with unpredictable post-closure maintenance and monitoring costs, possibly
over several decades, the economics of the containment strategy becomes unsustainable.
Such a high-cost, high-technology approach to landfill leachate management is generally
beyond the financial and technological resources of the less wealthy nations, and places
severe burdens on their economies. For instance, in third world countries with limited
water resources, the need to preserve groundwater quality is paramount, so expensive
containment strategies are adopted in the belief that they offer greatest protection to
groundwater. A final indictment of the containment strategy is that in delaying degradation
of waste, the present generations waste problems will be left for future generations to deal
with.
More cost-effective landfill management strategies take advantage of the natural
hydrogeological characteristics and attenua¬tion properties of the subsurface. The `dilute
and disperse' strategy employs the natural sorption and ion exchange properties of clay
minerals, and it has been shown that in appropriate situations it is effective in attenuating
landfill leachate and preventing pollution of water resources. Operated at sites with thick
clay overburden sequences, using a permeable cap to maximise rainfall infiltration and a
leachate collection system to control leachate migration, `dilute and disperse' is a viable
leachate management strategy. Hydraulic traps are relatively common hydrogeological
situations where groundwater ¯ow is towards the landfill, so effectively suppressing
outwards advective ¯ow of leachate. This approach is also best employed with a clay liner,
taking advantage of the attenuation properties of clays to combat diffusive ¯ow of
contaminants. These strategies are likely to guarantee greater protection of groundwater in
the long term.
1. Introduction
The concept of sustainability with respect to landfill management has been frequently
propounded recently
(e.g. Derham, 1995; Driessen et al., 1995). As with other environmental issues, the
attainment of sustain¬ability in the sphere of waste management has become the common
aspiration of legislators, regulators, local government and the waste industry at large.
Sustain¬ability, however, is a somewhat nebulous term, often used with a less than complete
understanding of its full import. In the context of landfills, it is here defined as `the safe
disposal of waste within a landfill, and its subsequent degradation to the inert state in the
shortest possible time-span, by the most financially efficient method available, and with
minimal damage to the environment'. The critical clause of the above defini-tion is the
reference to degradation of the waste over the shortest possible time-span, as this not only
controls the economics of the waste disposal process, but deter¬mines the potential for
environmental accidents during the period of activity of the waste. Furthermore, from a
purely moral standpoint it is important that this genera¬tions waste is rendered inactive as
precipitously as possible, so that our waste problems are not left for future generations to
deal with.
A sustainable waste management philosophy should encompass the following basic
principles:
² Reduction in the generation of waste.
² Waste streaming at source.
² Recycling and reuse.
² Pre-treatment of waste to minimise quantity and
volume. ² Landfilling of residual waste. ² Aftercare and rehabilitation of landfills after
closure. ² Each generation to deal with all of its own gener¬ated wastes.
The latter two principles may be the most proble¬matic, since realisation of both is
dependent upon the rapid degradation of waste going to landfill. Current EU landfill
management policies and legislation, favour the containment strategy of emission control as
an environmental protection measure. However, this is an extremely expensive option
which, as will be argued below, is likely to create more environmen¬tal problems in the
long term, than it supposedly resolves in the short term.
Landfill is critical to most waste management stra¬tegies, because it is the simplest,
cheapest and most cost-effective method of disposing of waste. In 1989, proportions of waste
going to landfill, ranged from about 60% in OECD countries (Stanners and Bour¬deau,
1995) to 100% in developing countries. Although in the future, waste minimisation and
recy¬cling programmes will reduce waste volumes, and other waste treatment options may
be developed, at the end of the day landfills will still be required to accommodate residual
wastes (Allen et al., 1997). In the developing world, a general lack of education and social
and technological infrastructure mitigates against the initiation of waste reduction
programmes or the development of alternative waste treatment options, thus ensuring that
in these regions, for the foreseeable future, landfills will continue to be the major method of
waste disposal (Allen, 1998).
In developing waste management policies, it is incumbent upon the richer nations to take
cognisance of the resources of poorer nations so that universal standards can be applied
that are within the technolo¬gical and financial capabilities of the poorer nations. Pollution
transcends national boundaries, and given the recent trend of economic groupings such as
the EU to develop standard pollution control legislation, it would seem logical to attempt,
where possible, to develop standards that, whilst being acceptable to the more developed
nations, are relatively simple and inexpensive to implement, thus making them achievable
by third world nations.
In the light of the foregoing, the trend of the more developed nations towards the
containment strategy of landfill management, which embodies an expensive highly
technological approach to the design and operation of landfills, is critically examined.
Evidence
and arguments are presented to suggest that this strat¬egy cannot bring about
sustainability in landfilling, but on the other hand could lead to serious future
environmental degradation of the type that the landfill industry would seek to avoid.
2. The containment strategy
Current EU landfill regulations, now enacted into law by all member states, have made the
installation of artificial lining systems and impermeable cappings mandatory for all
landfills, except for sites possessing
21
a suitable in situ low permeability (,1029ms ) natural liner, which can also ensure complete
contain¬ment of landfill emissions. Thus containment is now the only permissible landfill
management strategy within the EU. Other landfill management strategies, such as
hydraulic traps and `dilute and disperse', which take advantage of the natural
characteristics and properties of the subsurface, and which, in appro¬priate circumstances,
could be developed and oper¬ated at a fraction of the cost of a containment landfill, will not
in future even be considered by plan¬ners, since, under current legislation, they will no
longer be granted a licence. Thus the EU has favoured, to the exclusion of all other
strategies, an expensive purely technological approach to landfill management, at the
expense of cheaper natural solu¬tions.
The new EU regulations are based on the premise that artificial lining systems can wholly
contain all leachate produced during degradation of landfill waste, and so provide complete
protection to all groundwater, i.e. the concentrate and contain method of leachate control
(Gray et al., 1974). However, due to unremitting leakage problems, the requirement to
contain all leachate within the landfill, has necessi¬tated the design of more and more
elaborate liner systems, so that now it is standard to install composite two, three, or four
layer multibarrier clay-membrane systems (Tchobanoglous et al., 1993; Cossu, 1994, 1995).
These typically consist of sheets of synthetic membrane, most commonly high density
polyethy¬lene (HDPE), interlayered with clay mineral material, usually the smectite-rich
bentonite or a bentonite-enriched soil (BES). Two layer systems consist of a sheet of HDPE
overlying a 1 m thick mineral layer, three layer systems are composed of a 1 m thick
mineral layer sandwiched between two sheets of the synthetic membrane, whilst four layer
systems are represented by two sheets of membrane alternating with two 1 m thick mineral
layers. Leak detection and leachate collection systems are also generally built into the lining
designs. Daily covering of the waste with a clay-rich soil, in order to reduce wind¬blown
litter, odours, birds, vermin, ¯ies and visual intrusion, is a further requirement. On closure
of the landfill, an impermeable capping is installed to prevent infiltration of rainwater. The
cap commonly consists of a sheet of ¯exible membrane such as HDPE, or a sufficiently thick
layer of clay-rich soil
21
with a permeability of at least 1029 ms (Cossu, 1995). A landfill gas collection system is
usually installed immediately beneath the capping material, and completed cells are
generally landscaped, to ensure that virtually all rainwater runs off the surface.
The effective functioning of such a complex containment system is dependent on the careful
design and engineering of each site, strict quality control during installation of the liner
system, exces¬sive care during waste disposal operations, and high levels of maintenance
throughout the operational life of the landfill. Thus the containment strategy employs a
purely engineering solution to leachate manage¬ment, representing a high cost
technological approach, not only involving major expense in construction, but also costly
levels of maintenance (Mather, 1995).
3. Flaws in the containment strategy
3.1. Durability of artificial liner systems
3.2. Problems with clay liners
3.3. Unsuitability of sites
3.4. Impact on landfill waste degradation rates
3.5. Aftercare
3.6. Financial and social costs
3.7. Impact on third world economies
3.8. Failure of this generation to deal with all its generated waste
4. Alternative natural landfill management strategies
4.1. Dilute and disperse
5. Conclusions
Flaws in the current containment strategy, outlined above, are:
²
leakage problems and major uncertainties as to the long-term durability of synthetic
landfill lining systems;
²
chemical interaction of many clay liners, particu¬larly bentonite liners, with landfill
leachate, leading to an increase in hydraulic conductivity with time.
²
the inability of either synthetic or natural liners to suppress diffusive transport of
contaminants which, rather than advection, is the dominant contaminant transport
mechanism
²
the total reliance placed on the lining system, with little account taken of
geological/hydrogeological characteristics of sites being selected, and commonly no
secondary geological barrier to protect groundwater in the event of liner failure;
²
encapsulation of waste in a synthetic lining/ capping system, so inhibiting waste
degradation and thus prolonging the activity of the waste, possi¬bly for many decades;
²
the financial burden of long-term, post-closure maintenance and monitoring of
landfills;
²
the failure to take advantage of natural hydrogeo¬logical solutions to leachate
migration, or the natural filtration, sorption and ion exchange prop¬erties of clay-rich
overburden in order to attenuate leachate;
²
excessive costs in development and operation of containment landfills, making the
whole strategy uneconomic and financially unsustainable;
²
the unsuitability of such a high-technology, high-cost waste management strategy to
the financial and technological resources of the less developed third world nations;
²
the present generations waste problems being left for future generations to deal with.
The alternative landfill strategies can be repre¬sented as, on the one hand, high technology
solutions offering favourable short-term protection to the envir¬onment, but less certainty
of long-term protection, possibly resulting in serious environmental pollution in the longterm, as opposed to natural solutions, which offer possibly less guarantee of environmental
protection in the short term, but less likelihood of serious long-term environmental
pollution. Earth scientists (e.g. Mather, 1995; Allen, 1998) favour the latter approach,
whereas the engineering commu¬nity, in the belief that an engineering solution is super¬ior
to a natural approach, have promoted the current policy Ð which is being followed without
due regard to long-term cost or environmental impact.
The containment strategy employs a purely techno¬logical approach to the management of
leachate, ignoring the potential of natural solutions based on the confinement and
attenuation properties of the subsurface. High technology engineering solutions to pollution
control are usually expensive and rarely completely successful, and frequently have
negative impacts, the tendency being that the more sophisti¬cated the solution, the greater
the cost and mainte¬nance that they entail (Mather, 1995). A much more sensible and cost
effective approach typically involves some form of enhancement of natural processes by the
integration of a cheap, simple technology.
The containment approach has led to increasingly more complex technologies being applied
to over¬come each succeeding problem. The fundamental ¯aw in the strategy is that dry
entombment of waste inhibits its degradation, so prolonging the activity of the waste and
delaying, possibly for several decades, its stabilisation to an inert state. Given the
uncertainty regarding the durability of artificial lining systems over long timespans, the
potential for environmental pollution in the long term is significant. Furthermore the costs
of construction and operation of containment landfills are excessive, and the post-closure
maintenance and monitoring costs are ulti¬mately unpredictable. If a universal approach to
pollution control is to be adopted, a strategy relying on complex technologies, beyond the
financial and technological resources of the less advanced nations, is unlikely to succeed.
Landfill management options are curtailed by the in¯exibility of the current EU landfill
regulations and national legislation of member states, which not only makes a containment
approach mandatory to the exclusion of all other strategies, but militates against the use of
natural geological liners in the form of clay-rich overburden. The current legislation re¯ects
the triumph of the engineering solution over the natural solution in landfill management
strategies and represents an extreme approach to the protection of groundwater.
Finally, it should be pointed out that the current regulations render protection of all
groundwater as a mandatory requirement, regardless of whether the groundwater being
protected constitutes a material resource or not. Not all groundwater can be regarded as a
substantive resource, since a real resource only exists where it is readily available and
extractable in sufficient quantity at an acceptable cost. Groundwater only constitutes a
resource provided the porosity and hydraulic conductivity of the subsurface are sufficient
to provide an adequate supply at a sufficient yield for the purpose for which the
groundwater is being sought, which at the lowest common denominator could represent the
household supply to a single dwelling. Commonly, subsurface characteristics do not fulfil
these requirements, so in many areas ground¬water cannot be regarded as a resource. If
the ground¬water does not constitute a resource, then protection of such groundwater
becomes a very costly and futile exercise.
In the light of the foregoing, the conclusion that must be reached, is that many of the
problems asso¬ciated with containment are insurmountable, and that the containment
strategy and sustainability in landfill-ing are incompatible. It is therefore hard to conceive
of sustainability in landfilling ever being achieved via the containment approach, and
conversely it can be argued that if sustainability is to be attained, the containment strategy
becomes untenable.
References
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