Landfills and Incineration

How do modern landfills protect the environment?

The purpose of solid waste management is to remove wastes from living areas in a way that protects human health and the environment. Landfills fulfill this mission by sealing wastes away from the surrounding environment with liners and keeping them covered by more than six inches of dirt.

By sealing in wastes, landfills also control biodegradation, limiting the risk of explosive methane emissions. Uncontrolled biodegradation could also result in a toxic sludge that, if leaked, would endanger groundwater supplies. Modern landfills almost "mummify" waste. Recent landfill excavations have turned up 35-year-old newspapers that were still perfectly legible and 15-year-old corn that was still recognizable.

Is waste-to-energy incineration safe?

Yes. In 1989, the U.S. Conference of Mayors convened an international blue-ribbon panel of experts to discuss the health and safety impacts of waste-to-energy incineration. The symposium participants concluded that a properly equipped, operated and maintained energy recovery facility can operate within existing regulatory standards for human health and safety. The Clean Air Act of 1991 provided for an additional margin of security with tightened emissions standards. Furthermore, many communities are recognizing the importance of removing recyclables, as well as items such as batteries and household hazardous wastes, before incineration to reduce toxic components in incinerator ash.

The symposium participants found that, contrary to popular misconception, there is no evidence to link the incineration of PVC with increased dioxin emissions. Similar conclusions have been reached in a number of sources, including a 1987 study for the New York State Energy Research and Development Authority. Generally speaking, electricity is generated as safely through waste-to-energy incineration as it is through a power plant.

How much waste-to-energy capacity is there?

There are 121 energy recovery facilities operating in the United States, with a designed capacity of nearly 97,000 tons per day. An additional five facilities are under construction and 31 are in the planning stages. If all of these facilities come on line as planned, 19 percent of the nation's MSW will be processed by energy recovery facilities by the year 2000.

How do plastics contribute to waste-to-energy incineration?

Plastics are derived from petroleum or natural gas, giving them a stored energy value higher than any other material commonly found in the waste stream. In fact, one pound of plastics can generate twice as much energy as Wyoming coal and almost as much energy as fuel oil. When plastics are processed in modern waste-to-energy facilities, they can help other waste combust more completely, leaving less ash for disposal in landfills