Landfilling problems

The concept of biodegradable synthetic polymers was first proposed in the 1960s as a potential solution to the problem of plastics litter. This was initially welcomed by environmentally aware public, particularly in the USA, since it was perceived to be a possible solution to the landfill problem. Packaging producers in collaboration with corn growers were quick to respond to the public mood by adding corn starch to polyethylene. Carrier bags made from this material were claimed, without experimental evidence, to be biodegradable but the... 

New York City, with its 15,(XX) tons of trash daily, has now turned to recycling to alleviate its landfill problems. By 1995 at least 25 percent of its trash is expected to be recycled. 

Environmental The landfill problem and greenhouse gas emissions are reduced. It is a desirable process as energy is obtained from renewable sources like MSW or sewage sludge. 

Scavenging plastic-derived chemicals in landfills problems with plastics in terrestrial environments... 

In the past, removing metal and metalloid contaminants from soil has been impossible, and site clean-up has meant excavation and disposal in a secure landfill. An exciting new approach to this problem is phytoextraction, where plants are used to extract contaminants from the soil and harvested. Immobilization and Toxicity-Minimization. 

The principal disadvantage of absorption bleaching is the problem of disposal of spent bleaching clay. Oil absorbed on the clay is exposed to air and is generally too oxidized to recover. Furthermore, spontaneous combustion of the oil-laden clay is a possibiUty in a landfill. Incineration of the spent clay along with sohd municipal waste to recover otherwise wasted energy is an attractive possibiUty. 

Tines discarded in landfills tend to float on top of the ground mosquito infestation and illegal tine disposal cause problems which can be alleviated by recycling. Approximately 45% of scrap mbber, primarily as tines, is discarded in landfills (2). Private landfills may charge up to 3 per tine, and disposal costs at municipal landfills are ca 0.30—0.60 per tine (3,4), encouraging illegal disposal. As the tine piles grow, mbber recovery becomes more economical... 

Landfills in wet areas. Because of the problems associated with contamination of local groundwaters, the development of odors, and structural stabihty, landfills must be avoided in wetlands. If wet areas such as ponds, pits, or quarries must be used as landfill sites, special provisions must be made to contain or ehminate the movement of leachate and gases from completed cells. Usually this is accomplished by first draining the site and then lining the bottom with a clay liner or other appropriate sealants. If a clay uner is used, it is important to continue operation of the drainage facility until the site is filled to avoid the creation of uplift pressures that could cause the liner to rupture from heaving. 

I. Gas movement. In most cases, over 90 percent of the gas volume produced from the decomposition of sohd wastes consists of methane and carbon dioxide. Although most of the methane escapes to the atmosphere, both methane and carbon dioxide have been found in concentrations of up to 40 percent at lateral distances of up to 120 m (400 ft) from the edges of landfills. Methane can accumulate below buildings or in other enclosed spaces on or close to a sanitaiy landfill. With proper venting, methane should not pose a problem. 

Polychlorinated biphenyls (PCBs) zero 0.0005 Skin changes thymus gland problems immune deficiencies reproductive or nervous system difficulties increased risk of cancer Runoff from landfils discharge of waste chemicals... 

Styrene 0.1 0.1 Liver, kidney, and circulatory problems Discharge from rubber and plastic factories leaching from landfills... 

For question 9, the municipal landfill has had public relations problems with the community. There has been concern over both odor issues and possible groundwater contamination. Taking these concerns into consideration, can you develop addional arguments that make the investment more finacially attractive ... 

Attention must be given to the long term protection of people or the environment from hazards from abandoned equipment. Equipment that meets the criteria for disposal in a landfill—that is, it has been properly cleaned—may not be suitable for other uses. Problems such as the one related in the following example can be avoided by making the abandoned equipment unusable if it cannot be cleaned adequately. 

Where there is a landfill gas-generation problem, active (i.e. pumped) or passive venting, by way of stone-filled trenches at least 3 feet deep, may be needed. Where active... 

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