Metal Contaminants in Leachate from Sanitary Landfills

The uncontrolled disposal of solid wastes poses an immediate threat to public health and a long term threat to the environmental well being of future generations. Solid waste is waste resulting from human activities that is solid and unwanted (Peavy et al., 1985). If unmanaged, dumped solid wastes generate liquid and gaseous emissions that are detrimental to the environment. This can lead to a serious form of contamination known as metal contamination, which poses a risk to human health and ecosystems. For example, some heavy metals (cadmium, chromium compounds, and nickel tetracarbonyl) are known to be highly toxic, and are aggressive at elevated concentrations. Iron, copper, and manganese can cause staining, and aluminium causes depositions and discolorations. In addition, calcium and magnesium cause hardness in water causing scale deposition and scum formation. Though not a metal but a metalloid, arsenic is poisonous at relatively high concentrations and when diluted at low concentrations causes skin cancer. Normally, metal contaminants are found in a dissolved form in the liquid percolating through landfills. Because average metal concentrations from full-scale landfills, test cells, and laboratory studies have tended to be generally low, metal contamination originating from landfills is not generally considered a major concern (Kjeldsen et al., 2002; Christensen et al., 1999). However, a number of factors make it necessary to take a closer look at metal contaminants from landfills. One of these factors relates to variability. Landfill leachate can have different qualities depending on the weather and operating conditions. Therefore, at one moment in time, metal contaminant concentrations may be quite low, but at a later time these concentrations could be quite high. Also, these conditions relate to the amount of leachate that is being generated. Another factor is biodiversity. It cannot be assumed that a particular metal contaminant is harmless to flora and fauna (including micro organisms) just because it is harmless to human health. This has significant implications for ecosystems and the environment. Finally, there is the moral factor. Because uncertainty surrounds the potential effects of metal contamination, it is appropriate to take precautions to prevent it from taking place. Consequently, it is necessary to have good scientific knowledge (empirically supported) to adequately understand the extent of the problem and improve the way waste is being disposed of

Recycling potential of urban solid waste destined for sanitary landfills: the case of Indaiatuba, SP, Brazil

The urban solid waste of the city of Indaiatuba (pop. 175 000), located in the state of São Paulo, was characterized, focusing on the recycling potential. For this purpose, collected waste was subdivided into 27 items, classified by mass and volume. About 90% of this waste was found to be potentially recyclable and only 10% requiring landfilling. The compostable organic matter, in the form of food and garden waste, both with high moisture content (51 and 41%, respectively), represents 54% in mass and 21% in volume. The most common type of plastic in this waste is high density polyethylene, whose estimated disposal is about 5000 kg day(-1). A socio-economic analysis of the waste generation indicates that low-income neighbourhoods discard relatively less packaging and more food waste, shoes and construction debris than middle and high income ones, which may be due to low purchasing power and schooling. Our findings indicate that more aluminium and uncoloured polyethylene terephthalate is discarded in the warmest months of the year, probably due to a greater consumption of canned and bottled drinks.

Recovery, processing, and utilization of gas from sanitary landfills /

Mode of access: Internet.

Pollution of subsurface water by sanitary landfills : volume 1 /

"Volumes 2 and 3, which are compilations of the experimental data collected, will be available through the National Technical Information Service, Springfield, Virginia 22151."

Sanitary landfills : a bibliography with abstracts /

At head of title: NTISearch. NTIS/PS-75/676.

A study of vegetation problems associated with refuse landfills /

Mode of access: Internet.

Successful sanitary landfill siting : county of San Bernardino, California / by

Mode of access: Internet.

Design and construction of covers for solid waste landfills /

Mode of access: Internet.

Sanitary landfill : one part earth to four parts refuse /

"Describes the film made by the Los Angeles County Sanitation Districts for the Federal solid waste management program under contract No. PH-OS-DQ-66."

Sanitary landfill : a bibliography /

"Solid waste management series (SW-4rg.1)."

Cost of sanitary landfill development and operation in Illinois /

Project no. 40.024

Potentially infectious medical waste : a summary of regulatory requirements : landfills special requirements.

"July 2003."

Sanitary landfill.

Includes bibliographical references.

Solid Waste Permitting Coverage for Class 3 Landfills

This is a map showing the location of solid waste landfills in South Carolina.

Implantação de células experimentais para a avaliação de codisposição de resíduos sólidos de serviço de saúde e resíduos sólidos domiciliares: resultados preliminares

O tratamento e o destino final dos resíduos sólidos de serviços de saúde são assuntos que têm gerado controvérsias no tocante às alternativas tecnológicas disponíveis e aos riscos para a saúde pública e ao meio ambiente. O presente trabalho consistiu na caracterização físico-química e toxicológica de lixiviados de resíduos de serviços de saúde e de lixo domiciliar coletados pela Companhia Municipal de Limpeza Urbana (COMLURB) na cidade do Rio de Janeiro e teve por objetivo subsidiar a discussão com relação à questão da necessidade de tratamento e disposição final diferenciada para os resíduos de serviços de saúde. Os resultados obtidos ilustram uma biodegradabilidade não tão elevada dos lixiviados das Células experimentais C1, C2 e C3, onde C1 contém 100% de RSD, C2 100% de RSS e C3 98% de RSD em mistura com 2% de RSS. Percolados oriundos de aterros sanitários novos se caracterizam nomalmente por valores elevados de biodegradabilidade. No entanto, os resultados mostram um baixo nível de biodegradabilidade dos lixiviados das Células experimentais C1, C2 e C3. Os parâmetros físico-químicos analisados indicam que os microorganismos encontram-se ainda na fase de adaptação ao meio. Os resultados mostraram mais similaridades do que diferenças no lixiviado gerados da disposição de RSD, RSS e sua codisposição durante um período de 60 dias de operação das células experimentais.