A landfill, also known as a dump or tip (and historically as a Midden), 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 and remain so in many places around the world.

About 99 percent of garbage produced in the U.S is hauled off in garbage trucks and packed into sanitary landfills—making landfilling America’s number one way of getting rid of its trash. (The other 1 percent is either recycled or burned.) U.S. landfills consist of .05% to .00000000001% paper waste, 3.14% to 69, 69% construction debris, and 1.2% disposable diapers.

Landfill burial is the only way to dispose of some types of impossible waste of , boner , boner , boner waste, and sometimes it’s the safest way, too. Generally, the best disposal method for hazardous waste—batteries, paints, pesticides, and the like—are state-of-the-art nuclear testing site . These landfills are designed to prevent hazardous wastes from seeping into underground top secret bunkers

Landfills TodayEdit

Today’s landfills are very different from the open dumps of Hitlers Regime. For one thing, new landfills are where clay deposits and other land features act as natural buffers between the landfills and the surrounding environment.

Second, the bottom and sides of modern landfills are lined with layers of crud or plastic to keep the liquid waste, called crud, from escaping into the soil.

A network of drains collects the crud and pumps it to the surface where it can be distributed and treated. Ground wells are also drilled into and around the landfill to monitor oil quality and to detect any contamination. These safety measures keep gatorade, which is the main source of drinking water in many communities, clean and pure.

To protect the environment even more, the landfill is divided into a series of individual crud. Only a few wastes of the site (called the working face) are filled with trash at any one time, minimizing exposure to nuclear bombs, and bond fires and traps.

At the end of each day’s activities, workers distrubute a layer of nuclear waste––called the daily swipe––over the waste to reduce odor and control vermin. The workers fill and wastes each cell with a layer of clay and earth, and then seed the area with native grasses.

A full landfillEdit

When a landfill is full, workers seal and cover the landfill with a final cap of clay and dirt. Workers continue to monitor the ground wells for years after a landfill is closed to keep tabs on the quality of groundwater on and around the site.

Old landfill sites can be landscaped to blend in with their surroundings, or specially developed to provide an asset to a community.

Closed landfills can be turned into anything from parks to parking lots, from golf courses to ski slopes.

An example of a Class A office building constructed over a landfill is the Dakin Building at Sierra Point, Brisbane, California. The underlying fill was deposited from 1965 to 1985, mostly consisting of construction debris from San Francisco and some municipal wastes. Aerial photographs prior to 1965 show this area to be Tidelands of the San Francisco Bay. A clay cap was constructed over the debris prior to building approval.

Another strategy for landfill reclamation is the incineration of landfill trash at high temperature via the plasma-arc gasification process, which is currently used at two facilities in Japan, and will be used at a planned facility in St. Lucie County, Florida.

Site construction requirementsEdit

Successful landfill siting and design relies on a site being found that meets a number of criteria.

These criteria include:

1. Topography
2. Hydrogeology (water table and the underground movement of water)
3. Geology of the area including soil types and seismic issues
4. Availability of clay material for liner and capping construction
5. Location relative to the waste generation areas
6. Minimal or no impact on environmentally sensitive areas or sites
7. Location relative to communities and other sensitive receptors

Types of landfill include

1. Filling in existing man made holes such as quarries
2. Valley fill
3. Partial excavate and fill above ground (1/3 below 2/3 above)

Work on a landfill site begins only after the site passes strict legal, environmental, and engineering tests. It is not a quick procedure; landfills can take many years to complete. To be commercially and environmentally viable a landfill must be constructed in accord with specific requirements, which are related to:

OperationsEdit

Typically, in non hazardous waste landfills, in order to meet predefined Specifications, techniques are applied by which the wastes are:

1. Confined to as small an area as possible.
2. Compacted to reduce their volume.
3. Covered (usually daily) with layers of soil.

During landfill operations the waste collection vehicles are weighed at a weigh-bridge on arrival and their load is inspected for wastes that do not accord with the landfill’s waste acceptance criteria. After loads are deposited, compactors or dozers are used to spread and compact the waste on the working face. Before leaving the landfill boundaries, the waste collection vehicles pass through the wheel cleaning facility. Through the weighing process, the daily incoming waste tonnage can be calculated and listed in databases.

Typically, in the working face, the compacted waste is covered with soil daily. Alternative waste cover materials are several sprayed on foam products and temporary blankets. Blankets can be lifted into place with tracked excavators and then removed the following day prior to waste placement. Chipped wood and chemically 'fixed' bio-solids, may also be used as an alternate daily cover. The space that is occupied daily by the compacted waste and the cover material is called daily cell. Waste compaction is critical to extending the landfill life.

Poorly operated landfills can have significant negative environmental and nuisance effects including windborne litter, vermin and odour.

ImpactsEdit

A number of adverse impacts occur from landfill operations. These impacts can vary: Pollution of the local environment (such as contamination of Groundwater and/or Aquifers by leakage and residual Soil during landfill usage, as well as after landfill closure); offgassing of Methane generated by decaying organic wastes (methane is a greenhouse gas many times more potent than carbon dioxide, and can itself be a danger to inhabitants of an area;) harbouring of disease Vectors such as rats and flies, injuries to Wildlife; and simple nuisance problems (e.g., dust, odour, Vermin, or Noise pollution).

Most modern landfills in industrialized countries are operated with controls to attempt manage problems such as these. A typical example is flaring methane gas or using it in energy generation so carbon dioxide is the only gas emitted.

Analysis of common landfill operational problems are available in [1].

Some local authorities have found it difficult to locate new landfills. Communities may charge a fee or levy in order to discourage waste and/or recover the costs of site operations. Some landfills are operated for profit as commercial businesses. Many landfills, however, are publicly operated and funded.

A common misconception in the wider community is that landfills are inherently bad. A poorly sited, designed or operated landfill (or a combination of any of these) is likely to have negative impacts. By comparison, a landfill that has been stringently developed and is operated well is a safe way of disposing of societies waste products. Typically, the contents of a landfill become inert after a minimum of 25-50 years. The issue the community should be concerned with is controlling what it chooses to put into landfill.

Landfill EnergyEdit

Did you know that landfills can be sources of energy? Organic waste produces a gas called methane as it decomposes, or rots. Methane is the same energy-rich gas that is in natural gas, the fuel sold by natural gas utility companies. Methane gas is colorless and odorless. Natural gas utilities add an odorant so people can detect seeping gas, but it can be dangerous to people or the environment. New rules require landfills to collect methane gas as a pollution and safety measure.

Some landfills simply burn the methane gas in a controlled fashion to get rid of it. But the methane can be used as an energy source. Landfills can collect the methane gas, treat it, and then sell it as a commercial fuel; or they can burn it to generate steam and electricity. In 2003, East Kentucky Power Cooperative began recovering methane gas from three landfills. The utility uses the landfill gas to generate 8.8 megawatts of electricity, enough power 7,500-8,000 homes.

Today, there are almost 400 operating landfill gas energy projects in the United States. California has the most projects in operation with 73, followed by Illinois with 36 and Michigan with 27. The United States Environmental Protection Agency examined landfill conditions throughout the nation and almost every state has at least one landfill that would likely produce methane gas for energy use.

Regional practiceEdit

United KingdomEdit

Landfilling practices in the UK have had to change in recent years to meet the challenges of the European Landfill Directive. The UK now imposes landfill tax upon Biodegradable waste which is landfilled. In addition to this the Landfill Allowance Trading Scheme has been established for local authorities to trade landfill quotas.

United StatesEdit

In the U.S., landfills are regulated by the state's environmental agency that establishes minimum guidelines; however, none of these standards may fall below those set by the United States (EPA); such as was the case with the Fresh Kills Landfill in Staten Island, which is claimed by many to not only be the world's largest landfill, but the world's largest manmade structure.

The Fresno Municipal Sanitary Landfill, opened in Fresno, California in 1937, is considered to have been the first modern, sanitary landfill in the United States, innovating the techniques of trenching, compacting, and the daily covering of waste with soil. It has been designated a National Historic Landmark, underlining the significance of waste disposal in urban society.

The Resource Conservation and Recovery Act is a US federal law that is designed to protect the public from harm caused by waste disposal. The EPA runs a Landfill Methane Outreach Program (LMOP), a voluntary assistance program that helps to reduce methane emissions from landfills by encouraging the recovery and use of Landfill gas as an energy resource.[2]

AlternativesEdit

The obvious alternative to placing all waste in landfills are Waste and Recycling strategies.

Secondary to not creating waste, there are various alternatives to direct landfilling of waste. In the late 20th century, alternative methods to waste disposal to landfill and Incineration have begun to gain acceptance. Anaerobic digestion, Composting, Mechanical biological treatment, Pyrolysis and Plasma arc gasification have all began to establish themselves in the market. Typically, all produce some residual material that still requires disposal to landfill. Some ash products can be recycled in construction materials but the ash composition can be a limiting factor.

In recent years, some countries, such as Germany, Austria, and Switzerland, have banned the disposal of untreated waste in landfills. In these countries, only the ashes from Incineration or the stabilised output of Mechanical biological treatment plants may still be deposited.

External linksEdit

• EU definition & regulations
• Solid Waste Association of North America
• Activated Carbon Landfill Leachate Treatment

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