Content of lecture
18.1 Waste Composition 18.2 Site Selection
18.3 Groundwater
18.4 Slope/topography
18.5 Distance to settlement/ Public Involvement 18.6 Impact assessment
18.7 Legal Requirement
18: Planning a landfill
General
• Up to 1970s
– waste was a non-issue on political agenda, – unnoticed even by environmentalist groups.
• Proximity to waste producers was the most important criterion for selection of a site for a waste disposal. No
consideration was given to public health or environmental issues.
• In the 1970s
– cases of adverse health effects near waste dumps occurred.
18: Planning a landfill
Response from Authorities
• Setting up policy regarding waste management in
order to protect human health and environment in the future
– Regulatory requirements to reduce contaminant emissions from waste disposal/treatment facilities • Allocating resources to clean up abandoned
Nowadays siting is
very much of an issue
• Due to opposition from the general public, we often see that almost any site is taken if readily available!
• It seems that the siting process focuses
exclusively on getting public consent, rather than include consideration of any other relevant
aspect.
18.1 Waste Composition
18.1 Waste Composition
Waste from industrialized countries
Characteristics: high content of packaging made of paper, plastic, glass and metal
Moisture Content: Low Density: Low
Waste from developing countries
Characteristics: large amounts of inerts such as sand, ash, dust and stones and high moisture levels because of the high usage of fresh fruit and vegetables.
Moisture Content: High Density: High
18.2 Site Selection
18.2 Site Selection
… is the most important decision in developing and
implementing a waste management plan
A poorly chosen site will require high cost on:
waste transport
site development
site operations
environmental protection
18.2 Site Selection
18: Planning a landfill
Chronological development
18.2 Site Selection
18: Planning a landfill
Stages of a siting process
• Introductory stage
– making key decisions about • area to be served
• type and composition of waste to be landfilled • target lifetime (minimum 10 years)
– developing a work plan for site selection • Main stage
– Preliminary site selection
– Identification of the selection criteria
– Decision of relative importance of the selection criteria – Establishing a ranking of the sites
18.2 Site Selection
18: Planning a landfill
Making the key decisions • Establish current situation
– review existing facilities
– calculate remaining capacity & find waste composition
• Define future needs
– estimate future waste quantities
– estimate future (changes of) waste composition
Introductory Stage
Work plan for site selection
Elements of the plan are dictated by legal and administrative procedures and requirements in force within the area.
Preliminary site selection
- Define search area based on
natural and administrative constraints hauling distances.
- Make use of maps and visit the sites. - Apply preliminary selection criteria.
- Estimate costs involved (economies of scale play a role). - Prepare a list of sites, along with their pros and cons
- Size of the site and access
- Safety (proximity of airport etc.)
-Country planning constraints (drinking water aquifer, protected nature area etc. )
- ……
Final site selection criteria
18: Planning a landfill
18.2 Site Selection•Geological aspects
•Hydrogeological aspects
•Public health/public acceptance -near residential area
-near places of religious, cultural or historical importance
-near agricultural sites land
-near drinking water wells, ponds, river (in criteria of country planning as well)
18.3 Groundwater
18.3 Groundwater
Depth of the water table
Permeability of Geological strata
Type of Geological strata
Toxicity of the leachate contaminants
Groundwater flow direction
The groundwater contamination by landfill is determined by following factors
18.4 Slope/Topography
18.4 Slope/Topography (Geological aspects)
- extreme topography
- unstable subsoil areas
- geologically active faults
- seismic impact zones
Following potentially unstable geological conditions are to be avoided by Landfill developers
Ranking the sites
Constraint mapping (using selection criteria)
Walkover surveys using a checklist
Conceptual design for each site
Site investigations
Feasibility report and EIA (environmental impact
assessment)
• Homogeneous geology with no fractures • Geotechnically stable subsoil
• Base of the site naturally impermeable • Thick unsaturated layer below the base • Site far from an aquifer
• Site far from surface water bodies (sea, lake, river) • Site that people accept
What is an ideal site
18.5 Distance to Settlement
18.5 Distance to Settlement/Involvement of
public
• Nuisance caused by a landfill – nuisance by lorry traffic
– nuisance by odours, birds, littering, scavengers • Economic impacts - decrease of economic value of
houses near a landfill
• Health and environmental impacts
• Social impacts - diminished quality of life
18.5 Public Involvement
18: Planning a landfill
Involvement of public:
objectives
• Public understands needs and proposals.
• Issues raised by public are heard and addressed. • Authority is responsive to public.
18.5 Public Involvement
18: Planning a landfill
Disadvantages of public involvement
• Public may become completely consumed by some details or issues of relatively lesser
importance.
• Disinformation can be spread. • It can cause damaging delays.
18.5 Public Involvement
18: Planning a landfill
Advantages of Public Involvement
• People can express their concerns and get answers to their questions.
• It effectively ensures that authorities take opinions of public into account.
• Important information may be gathered from people, that may otherwise be missed.
18.6 Pollution risk
18.6 Impact Assessment/Pollution risk
Pollution risk impact assessment is a process of estimating the likelihood of occurrence of harmful effects by landfills
Example
Risk analysts say:
At 0.1µg/L of certain chemical in drinking water (e.g. heavy metal) risk of adverse effect on human health is 10-6.
18.6 Pollution risk
HAZARD PATHWAY RECEPTOR / TARGET
WASTE MIGRATION PEOPLE AND through soil, water, air ENVIRONMENT
Basic concept of risk
18.6 Pollution risk
Risk of pollution by landfills depends on site characteristics, landfill technology and waste composition.
Landfills can cause pollution if waste constituents
(or products of their decomposition and reactions)
reach the environment. This occurs mainly by
migration of
– liquid (leachate) into subsoil, groundwater and adjacent surface water bodies
– gas (landfill gas, biogas) into atmosphere.
18.6 Impact Assessment
• Risk source release assessment
– What is the risk of failure of landfill control measures? • Exposure assessment
– How can contaminant migration take place? • Consequence assessment
– What effects might an exposed individual experience? • Risk estimation
– How can results of previous stages be integrated? – What are the uncertainties?
18.7 Legal Requirements- JOKO?
•Landfill planning involves the most important
decision to reduce cost of waste disposal and
environmental impacts
•The potential impact on the groundwater is one of the most important aspects
•Landfill planning and site selection are best carried out as a systematic stepwise process
