1. Average person produces 1700 lbs of MSW per year
Solid Waste
Any unwanted material that is not liquid or gas
98.5% is from mining, oil & gas production, industry, sewage sludge and agriculture
1.5% is known as municipal solid waste (MSW) from homes and businesses (aka garbage)
Average person produces 1700 lbs of MSW per year

2. How do we deal with solid waste?
1. Burn/Incinerate
Advantages
Reduced trash volume
Less need for landfills
Low water pollution
Disadvantages
High cost
Air pollution (especially toxic dioxins)
Produces a highly toxic ash
Encourages waste production
16% of MSW is burned in mass-burn incinerators

3. 2. Land disposal
Sanitary landfill  solid wastes are spread out in thin layers, compacted and covered daily with a fresh layer of clay or plastic foam
In modern landfills the bottom is covered with an impermeable liner to collect leachate
Rainwater contaminated as it percolates through the solid waste
Collected leachate is pumped from the bottom, stored in tanks and sent to a sewage treatment plant
More than half of the MSW in the U.S. is buried in sanitary landfills

4. Methane produced by anaerobic bacteria must have a way to escape the landfill or be collected.
Monitoring wells surround the landfill to check the groundwater and make sure no contamination is occurring.
Some landfills collect the methane produced and use it to generate electricity  cogeneration

5. Hazardous Waste Any discarded solid or liquid that . . . .
contains one or more toxic, carcinogenic,
mutagenic, or teratogenic compounds at
levels that exceed limits
catches fire easily
is reactive or unstable enough to explode or release
toxic fumes
is capable of corroding tanks, drums, or barrels

6. Official US definition does NOT include
radioactive waste
hazardous materials discarded by
households
mining and oil drilling wastes
This means 95% of hazardous waste is not regulated by hazardous waste laws

7. 80% of hazardous waste is incinerated
How do we deal with hazardous waste?
1. Burn/Incinerate
80% of hazardous waste is incinerated

8. 2. Detoxify * Bioremediation  using microorganisms and enzymes to
convert toxic or hazardous substances to harmless compounds
effective for organic wastes,
pesticides, liquid fossil fuels, PCBs,
and organic solvents
* Phytoremediation 
using plants as ”pollution sponges” to filter and remove contaminants
effective for organic solvents, radioactive metals and toxic metals such as lead and mercury

9. 3. Land disposal * Deep underground wells
wastes are pumped under pressure through a pipe into dry, porous geologic formations far below aquifers
* Surface Impoundments
excavated depressions such as ponds or pits into which liquid hazardous waste are drained and stored
* Secure landfill
* Above ground buildings
two-story buildings of reinforced concrete

10. Resource Conservation and Recovery Act
Hazardous waste LAWS
Resource Conservation and Recovery Act
aka RCRA (RICK-ra)
Requires the EPA to identify hazardous wastes and set
standards for their management by states
Firms that store, treat or dispose of more than 100kg
(220 lbs) of hazardous waste per month have to have
a permit
Permit holder keep track of waste from point of
origin to disposal facility

11. aka CERCLA or Superfund Act
Comprehensive Environmental Response,
Compensation, and Liability Act
aka CERCLA or Superfund Act
identifies abandoned hazardous waste dump sites
and underground tanks leaking toxic chemicals
protects and if necessary cleans up groundwater near such
sites
cleans up the sites
when they can be found, requires responsible parties to
pay for the cleanup
the worst sites are put on a National Priorities List (NPL)

12. Brownfields are abandoned industrial and
commercial sites that are in most cases contaminated