APES 8

8.9: SOLID WASTE DISPOSAL

Types of solid waste: Municipal solid waste and E-waste

Municipal solid waste: solid waste such as trash, litter, and garbage from cities (households, businesses, schools, etc.)

E-waste: old computers, TVs, phones and tablets

Why is e-waste hazardous: due to metals like cadmium, lead, mercury, and PBDEs

Effect of e-waste being thrown away with Municipal solid waste: it can leach endocrine disrupting chemicals out of landfills; they should be disposed of at special facilities

Features of sanitary landfills: clay/plastic bottom liner, leachate collection system, methane recovery system, and clay cap

Clay/plastic bottom liner: layer of clay/plastic on the bottom of a hole in the ground; prevents pollutants from leaking out into soil/groundwater

Leachate collection system: system of tubes/pipes at bottom to collect leachate (water draining through waste and carrying pollutants) for treatment and disposal

Methane recovery system: system of tubes/pipes to collect that methane produced by anaerobic decomposition in the landfill; methane can generate electricity

Clay cap: clay-soil mixture used to cover the landfills once its full; keeps out animals, keeps in smell, and allows vegetation to regrow

Why do landfills generally have low rates of decomposition: low O2, moisture, and organic material combination

Things that should not be landfilled: hazardous waste (motor oil, cleaners, electronics, car batteries), metals like copper and aluminum, and old tires

Things that should be landfilled: cardboard/food wrappers that have too much food residue and can't be recycled, rubber, plastic films, Styrofoam

Things that should be recycled or composted: food, yard waste, and paper

Environmental impacts of landfills: groundwater contamination with metals, acids, and bacteria if leachate leaks through and GHG release from decomposition

What is waste in landfills incinerated for: to reduce the volume that needs to be landfilled

Drawbacks of waste incineration: releases CO2 and air pollutants