Agenda - Council - 09/13/1982 - Special

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I I I I I I I I I I I I I I I I I I SUMMARY Solid waste disposal facilities, especially landfills, can adversely affect the environment and cause the host community other problems as well. There are basicalqy two approaches to dealing with such impacts. The first is to reduce or mitigate the negative effects as much as possible. The second is to provide some form of compensation to local residents and the host community for impacts that cannot be eliminated altogether. Potential environmental impacts from waste disposal facilities are many and varied: surface water and groundwater pollution; air pollution; truck traffic, noise and litter; and loss of vegetation or wildlife. Of all waste disposal facilities, landfills pose perhaps the greatest water pollution threat. Rain and snowmelt can seep into a landfill, picking up contaminants, then flow over land into surface waters or seep through the soil into lakes and streams° The risk is highest during the operation of a landfill rather than after closure. Groundwater contamination can result if leachate (water contaminated by land- fill refuse) seeps into the underground water table or aquifer, a porous layer.. of rock often used as a source of well water. Contamination of the groundwater can occur during a landfill's operation but it remains a serious risk even after closure. The best method to deal with the threat of surface water and groundwater pol- lution is to find an environmentally suitable location for the facility and design it to avoid such problems. For example, a site should have adequate but not excessive drainage, and underlying soils that inhibit the seepage of leach- ate into the groundwater. Also, controlling surface water runoff can help reduce the threat of surface water pollution. Methods include covering refuse with a layer of soil immediately after it is dumped in the landfill, and chan- neling and storing runoff to prevent it from flowing into nearby lakes or streams. To head off groundwater contamination, two methods are often used. One is to install an impervious layer of material under the landfill site to reduce the risk of leachate seepage into the groundwater. Another method involves use of a leachate collection system. Such a system uses underground collection devices and pumps to remove the leachate from the ground and bring it to the surface for disposal. Preventing hazardous wastes from being dumped in the landfill is important to ensure that risks of leachate leakage are kept to a minimum. In short, the less dangerous the refuse, the less threatening the leachate would be. Air pollution is another by-product of sanitary landfills. Such pollution includes exhaust emissions from trucks, dust and gases. In addition, if gas recovery systems are installed at sanitary landfills to collect and process methane gas (produced by the decomposition of organic matter), various pollut- ants may be emitted. Dust can be controlled by oiling or watering access roads to the landfill, by keeping the working part of the landfill away from the wind, and by using trees, shrubs and other vegetation for windbreaks. Exhaust emissions can be reduced by controlling truck traffic on access routes and by keeping vehicles properly tuned.