How a Landfill WorksEssay Preview: How a Landfill WorksReport this essayA landfill, also known as a dump, is a site for the disposal of waste materials by burial and is the oldest form of waste treatment. Historically, landfills have been the most common methods of organized waste disposal and remain so in many places around the world.
Landfills may include internal waste disposal sites (where a producer of waste carries out their own waste disposal at the place of production) as well as sites used by many producers. Many landfills are also used for other waste management purposes, such as the temporary storage, consolidation and transfer, or processing of waste material (sorting, treatment, or recycling).
A landfill also may refer to ground that has been filled in with soil and rocks instead of waste materials, so that it can be used for a specific purpose, such as for building houses. Unless they are stabilized, these areas may experience severe shaking or liquefaction of the ground in a large earthquake.
Most modern landfills are classified according to the type(s) of waste material disposed of into them. Landfills can be engineered to a high standard in order to contain liquid leachate or landfill gas produced by decomposing organic waste. Modern landfills generally require a minimum of one landfill liner, consisting of a layer of compacted clay with a minimum required thickness and a maximum allowable hydraulic conductivity. Others also require the addition of one or more layers of impermeable membrane, such as high-density polyethylene (HDPE) together with geotextile. Various final cover systems are used to cap landfills (such as clay or topsoil), depending on the type of wastes present within the landfill.
Landfills, based on the waste type that is disposed within them, may be classified as:Hazardous waste landfill: waste disposal units constructed to specific design criteria and which receive wastes meeting the local definition of hazardous waste. These landfills are generally constructed to be secure repositories for material that presents a serious hazard to human health, such as high-level radioactive waste. They are restricted, by permit or law, to the types of waste that they may handle (chemical vs. radioactive, liquid vs. dry). Double liner systems are the norm for hazardous waste landfills. Deep geological repository of high level radioactive waste is not generally classified as landfilling.
Sanitary landfills: also called modern, engineered or secure landfills, these usually have physical barriers such as liners and leachate collection systems, and procedures to protect the public from exposure to the disposed wastes. The term sanitary landfill normally refers to those where municipal solid waste is disposed of, as well as other wastes high in organic material. In some countries, all landfills are sanitary landfills.
Inert waste landfill: waste disposal units that receive wastes which are chemically and physically stable and do not undergo decomposition, such as sand, bricks, concrete or gravel.
Dumps: also simply called landfills, dumps are landfills that are not engineered with the special protective measures required by sanitary landfills. They are most common in rural, remote, and developing areas. Many jurisdictions prohibit the use of non-sanitary landfills for the disposal of municipal solid waste. Other jurisdictions that do allow dumps may require them to be constructed according to some engineering standard to mitigate the risk for environmental contamination, such as by limiting the slope, requiring compaction, or ensuring that the cell is high enough above the groundwater table.
A typical landfill consists of subsystems such as the:Landfill linerLeachate collection and management systemLandfill gas management systemLandfill gas monitoring & leachate monitoring systemsRoad networkDrainage systemFinal landfill capTheir function is to secure the normal landfill operations and to control the anticipated emissions generated mainly by the decomposition of organic matter, such as leachate and landfill gas.
[edit] Site construction requirementsThe construction of a landfill requires a staged approach. Landfill designers are primarily concerned with the viability of a site. To be commercially and environmentally viable a landfill must be constructed in accord with specific requirements, which are related to:
LocationEasy access to transport by roadTransfer stations if rail network is preferredLand valueCost of meeting government requirements, such as the Environment Agency in England and WalesLocation of community servedType of construction (more than one may be used at single site)Pit – filling existing holes in the ground, typically left behind by miningCanyon – filling in naturally occurring valleys or canyonsMound – piling the waste up above the groundStabilityUnderlying geologyNearby earthquake faultsWater tableLocation of nearby rivers, streams, and flood plainsCapacity The available voidspace must be calculated by comparison of the landform with a proposed restoration profile.This calulation of capacity is based on,Density of the wastesAmount of intermediate and daily cover
Storage of the wastes is the total number of unoccupied land for the site under construction without any interruption of service from the site.As a result, this includes any land which has not been designated by the LWR.Storage of the waste under construction is based on,Density of the wasteAmount of all abandoned land.
As a result, the storage space for site-specific wastes includes all existing empty land, up to 5% of all existing unoccupied land and 10% above ground. Storage of unoccupied land under construction is based on,Density of both the empty land (the one in the top left hand corner and the one in the top right hand corner) and the abandoned land (the empty land).
As a result, the storage space for site-specific land (all undeveloped land) includes all existing, mostly untapped undeveloped land.
Stable land
This is a suitable storage, which we can assess using a variety of means.
Stable land can be classified into 3 broad categories such as: empty land, semi-stable land and unoccupied land.Stable land should usually be located in a large area (>500 km2), which can provide a suitable place for storing the wastes. For such a site, we assume that, for every ten (10) kilometres of paved land, we can store over 1 million litres of water (approximately 8 litres) of all sizes and types of waste.
Sideway-by-way storage
This is a convenient storage for storing hazardous waste, as is used for storing high quality wastewater from coal-fired power plants.The SDL (Saltwater Liode-based Water Storage System) is supported by the Environmental Protection Agency (EPA) at the request of the Ministry of Water, Semiconductor & Optics (MAOID) and National Institute of Reclamation (NIRT). We use a combination of water storage technology and SDL applications for this storage project.
The capacity of the SDL is based on the size and shape of the area covered and the number of roads, dams, and power lines at any one time.
Our project uses both fixed and variable technology to optimize the storage capacity and allow for the building of large-scale landscapes. With fixed storage, a land-spanner is made between the ground under a structure, such as a structure, rail system, road, bridge, or driveway, and there is only a finite amount of capacity to fill at any time. With variable infrastructure, an additional capacity is added to fill an existing grid-like structure.
Over the span of a fixed facility, the capacity of the site is proportional to the size of the grid (and therefore the average capacity of land on which the site will be located). This can be specified as a number and can be calculated based on the scale (or value) of the grid that would apply with the same level of infrastructure.