Landfill sites closed

Campbell, D J.V. (1991b) The monitoring and control of landfill gas migration, in Proc. Symp. Containment of pollution and redevelopment of closed landfill sites, Leamington Spa, Construction Marketing, 2.2/1 - 2.2/11. 

Barry D. L., Summersgill I. M., Gregory R. G. and Hellawell E. (2001) Remedial engineering for closed landfill sites. CIRIA Report C557, CIRIA, London, UK. 

In the U.S. about 8% of the energy is provided by biomass and almost 90% of this comes from the combustion of wood and wood residues. The use of biomass increased from an installed capacity of 200 megawatts in 1980 to over 7,700 megawatts in 1990. The search for cleaner fuels and landfill restraints are the main reasons for increased biomass utilization. The cost of waste disposal has soared and landfill sites are closing faster than new ones are opening up. The Environmental Protection Agency (EPA) estimated that between 1978 and 1988, 70% of the nation s landfills, about 14,000 sites closed. 

The cost of waste disposal has soared and landfill sites are closing faster than new ones are opening up. The Environmental Protection Agency (EPA) estimated that between 1978 and 1988, 70% of the nation s landfills, about 14,000 sites closed. 

Veterinary medicines are also known to leach from landfill sites. In Denmark, high concentrations (mg/kg) of numerous sulfonamides were found in leachates close to a landfill site where a pharmaceutical manufacturer had previously disposed of large amounts of these drugs over a 45-year period. Concentrations dropped off significantly tens of meters down gradient, most probably due to microbial attenuation. Although this is recognized as a specific problem, disposal of veterinary medicines to landfill should nevertheless be considered a potential route for environmental contamination. 

The means by which gas control is achieved is dependent upon the local conditions. For example, the type and extent of controls for buildings at some distance from a landfill are likely to be quite different from those in buildings constructed on the site of a closed landfill. 

LEW is generated from hospitals, laboratories and industry, as well as from the nuclear fuel and defense program cycle. It comprises paper, rags, tools, clothing, filters, and other lightly contaminated materials that contain small amounts of mostly short-lived radionuclides. It is not dangerous to handle, but must be disposed of more carefully than normal garbage. Often it is buried in shallow monitored landfill sites. To reduce its volume, it can be compacted or incinerated (in a closed container) before disposal. Worldwide it constitutes 90% of the volume but only 1% of the radioactivity associated with all radioactive waste. 

There is a high-risk landfill site nearby and gas migration is known to be occurring from it close to the property being considered. 

Shredded tyres can be used in the construction of landfill sites as a replacement for other construction materials. The areas that they are used in include lightweight backfill in gas-venting systems, leachate collection systems and operational liners. Shredded waste tyres can also be used to cap, close or daily cover landfill sites [75]. Their use as a backfill material and cover material can be more cost-effective than the use of other fill materials, as they can be shredded on site rather than being transported in for that particular purpose. 

The primary purpose of the HELP model is to provide water balance data with which to compare design alternatives for conventional barrier-type covers installed on landfills with bottom liners. It provides a tool for both designers and permit writers and is applicable to open, partially closed, or fully closed sites. 

In relation to the obvious environmental pollution potential of landfilling of MSW, few new landfills are now sited. Additionally, the U.S. Environmental Protection Agency (EPA), in a report to Congress, projected that 40% and 82% of the current landfills in operation today will be closed by the year 1993 and 2013, respectively (11). Therefore, as the standard route of disposal shrinks, new avenues for disposal must be identified and quickly commercialized to meet the disposal demand. 

Fresh Kills had many of the same problem as other landhlls, however. At one point, authorities reported that it was leaking up to 2 million gallons (7.6 million liters) of liquid wastes into the ground each day. Finally, in 2001, Fresh Kills had reached capacity there was no more room for wastes, and New York City s last landfill closed down on March 22 of that year. The city was forced to find another site to dump its solid wastes. 

Subtitle D of RCRA covers nonhazardous solid waste generators, transporters, treatment facilities, storage facilities, and disposal sites. Extensive rules governing municipal solid waste landfills (MSWLs) have been developed, including how to design, construct, operate, monitor, and close a landfill, as well as leachate systems and caps. The nonhazardous waste regulation is left for the states. 

Exempt Waste. Waste classified as exempt would be regulated as if it were nonhazardous, and would be generally acceptable for disposition as nonhazardous material (e.g., disposal in a municipal/ industrial landfill). As noted in Section 1.4.1, disposal is the only disposition of exempt materials considered in this Report. Limits on concentrations of hazardous substances in exempt waste would be derived based on an assumption that the risk or dose to a hypothetical inadvertent intruder at a disposal site should not exceed negligible levels. The use of a negligible risk or dose to determine exempt waste is based on an assumption that a disposal facility for nonhazardous waste could be released for unrestricted use by the public soon after the facility is closed. 

In summary, transport and spreading of dissolved landfill leachate pollutants in aquifers are governed by advection/dispersion. The local hydrogeology at the site in terms of water table mounds and seasonal variation in flow field may enhance the spreading horizontally and vertically. Density effects due to high concentrations of inorganic compounds may increase vertical transport, but the understanding of density transport in leachate plumes is poor. Density transport is likely to be most important close to landfills but less so as dilution of the plume increases. 

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