8.9 Solid Waste Disposal

landfills

these must confront two large environmental porblems


1. leachate
2. Gases

leachate

contaminated water that passes through MSW into the soil and waterways

sanitary landfills

aim to contaminate the surrounding environment as little as possible


1. plastic or clay bottom layer
2. stormwater collection
3. leachate collection
4. methane recovery for energy use
5. clay and soil cap

decomposition depends on

1. composition of the trash
2. conditions needed for microbial decomp

incineration

burn waste to reduce volume and mass; sometimes can generate electricity or heat (waste-to-energy system)

* produces air pollution

ash

residual non organic material that does not combust

e waste

only 2% of the waste stream. contains toxic components

ocean dumping

* prohibited in 1972 by ocean dumping act
* animals ingest trash and become entangled

methane

anaerobic decomposition produces this