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SOLID WASTE
11 billion tons each year
Waste stream- the steady flow of varied wastes produced
In our dumping system processes mix & crush everything together separation is expensive
Toxic materials are dispersed throughout tons of miscellaneous garbage
WASTE DISPOSAL METHODSOPEN DUMPS
Predominant form in developing countries
Garbage is left in giant piles exposed to wind, rain, rats, flies, and other vermin
Illegal dumping in developed countries
Example- 200 million litres of waste motor oil is poured into sewers soak into ground water
Oil can pollute large quantities of water with a small amount
OCEAN DUMPING
Packaging-bottles, cans, plastic containers
Fishing gear- nets
Sewage sludge
80 million m3 of dredge soil is dumped
Contaminates with heavy metals and toxic compounds
LAND FILLS
Sanitary landfills- solid waste disposal is regulated and controlled
Compacted every day and covered with a layer of dirt, which helps control pollution
1994- land fills in US have to control hazardous materials
An impermeable layer underlies and encloses the storage areas
Drainage systems are around liner to catch drainage and monitor leaking chemicals
Location
Un-faulted rock formations
Away from rivers, lakes, floodplains and aquifer recharge zones
Becoming expensive disposal method because of rising land costs
Methane recovery-
Natural product of decomposing garbage deep in a landfill
Can be collected and burned
Could provide enough electricity for a city of 1 million people
SANITARY LAND FILL
A waterproof
lining is now
required to
prevent leaching
of chemicals into
underground
aquifers
EXPORTING WASTES
Poorer populates are more likely to be recipient of dumps, waste incinerators, and unwanted land uses
Often toxic wastes
“recycle” as asphalt- what happens when the road wears away?
“Land farmed”
Sold as fertilizers or soil amendments
Not subject to regulation because not intended for human ingestion
INCINERATION
Energy recovery/ waste-to-energy- burning
Heat derived from incinerated refuse is a useful resource
Can produce steam used directly for heating building or generating electricity
Reduces land fill need
Types of municipal incinerators-specially designed burning plants are capable of burning thousands of tons of waste per day
Refuse derived fuel- can be sorted to remove unburnable or recyclable meterials
Mass burn- dump everything, burn as much as possible Avoids expensive and unpleasant job of sorting
Causes greater problems with air pollution and corrosion of burner grates and chimneys
10%-20% of original mass
Contains toxic components environmental hazard if not disposed properly
Incinerator cost and safety
Initial construction- $100 -$300 million
Pay in long run lifetime of landfills will be extended
Environmental Safety
High levels of dioxin, furans, lead and cadmium in incinerator ash
Concentrated in fly ash( lighter, air borne particles capable of penetrating deep inside the lung
Problem: Enough Garbage?
Percentage of municipal solid waste recycled, composted, incinerations and landfilled in some developing countries
Click icon to add picture
SHRINKING THE WASTE STREAM
RECYCLING The reprocessing of discarded materials in to new useful products
into same product( ie. New cans) or entirely new products (ie. Newspapers cellulose insulating)
Contamination- can cost more to remove contaminants that the material is worth
economic benefits-saves money, energy, raw materials and land
Money- many recycling programs cover their own costs with material sales
Lowers demand for raw materials
Reduces need for energy to create new materials Ex. Producing aluminum cans from scrap saves 95% of energy
Reduces litter
COMMERCIAL SCALE RECYCLING
Composting- a method in which natural aerobic decomposition reduces organic debris to a nutrient rich soil amendment
Save land fill space
Can make a profit
Ferment organic waste produce Methane sell energy and fertilizer
Can recycle building debris
Mulch, crushed stone, gypsum, recyclable metal and paper
Thermal conversion process- pressure cooks manure, plastics, paper processing waste, tires, sewage
Extreme heat and pressure reduce molecules to simple hydrocarbons-oil, gasoline, natural gas
DEMANUFACTURING
The disassembly and recycling of obsolete products such as TVs and computers
E-waste- computers, cell phones, TVs, printers
Reduces environmental costs
Cradle to grave- manufactures are responsible for taking care of what they produce
REUSING
Saves cost of remanufacturing
Ex. Selling from junkyards
Producers reusing glass containers (average 15 round trips before too scratched to use)
National companies not in favor of b/c would take too much energy
In some developing countries people make a living off of scavenging from city dumps
REDUCING
Packaging- 50% domestic waste (volume)
Reduce
No packaging
Minimal packaging
Reusable packaging
Recyclable packaging
When necessary can use
Photodegradable plastics- breakdown when exposed to UV radiation
Bio degradable plastics- incorporate such materials as cornstarch that can be decomposed by micro organisms Often don’t decompose completely
Largely eliminates recycling as an option
MOST IMPORTANT- REDUCE, REUSE, RECYCLE
HAZARDOUS AND TOXIC WASTESRECYCLED, CONTAINED OR DETOZIFIED
Hazardous waste- any discarded material, liquid or solid, that contains substances known to be
Fatal to humans or laboratory animals in small doses
Toxic, carcinogenic, mutagenic, or teratogenic to humans or other life forms
Ignitable with a flash point of less than 60°C
Corrosive
Explosive or highly reactive
Some materials can be exempt
In small quantities
In an approved waste treatement facility for the purpose of being beneficially used, recycled, reclaimed, detoxified or destroyed
Most is recycled, converted into non hazardous forms, stored or otherwise disposed of
Problem: orphan wastes-left behind by abandoned industries
FEDERAL LEGISLATION
Resource Conservation and Recovery Act (RCRA) 1976
Requires rigorous testing and management of toxic and hazardous substances
Requires generators, shippers, users and disposers of materials to keep meticulous account
Comprehensive Environmental Response, Compensation and Liability Act (CERCLA or Superfund)
1980, modified 1984 under the Superfund Amendment and Reauthorization Act (SARA)
Aimed at rapid contianment, cleanup or remediation of abandoned toxic sites
Authorized EPA to undertake emergency actions when threat exists, can bring auit against responsible parties
SARA- community has the right to know, and established state emergency response plans that gives citizens access to the toxins in their community Toxic Release Inventory- requires 20,000 facilities or report on releases of 300
toxic materials
SUPERFUND SITES
36,000 seriously contaminated in US
1997- 1,400 sites on National Priority List (NPL)
Superfund-
Provides immediate response to situations that pose imminent threats
Clean up
1993-2000- 757 of 1500 NPL sites cleaned
Greatest concerns-most often detected
Contamination sites-
Old industrial facilities-smelters, mills, petroleum refineries, chemical manufacturing plants
Mining districts
Railroad yards, bus repair barns
1. Lead2. Trichloroethylene3. Toluene4. Benzene5. PCBs6. Chloroform
7. Phenol8. Arsenic9. Cadmium10. Chromium
HAZARDOUS WASTE SITES
Hazardous waste sites
found usually around the
Great Lakes, the “Rust
belt” or the gulf coast
Here- on EPA priority
cleanup list, sites on
aquifer recharge zones are
an especially serious
threat because ground
water contamination can
be difficult and costly, and
some times impossible.
BROWNFIELDS
Large areas of contaminate land
Abandoned because of real or suspected pollution
Liability risks deter developers
Some people think the standards for clean up are too high-
Ex. Water contamination must be to drinking water standards
Former congressman Jim Florio, and principal author of the original Superfund Act says “ It doesn’t make any sense to clan up a rail yard in downtown Newark so it can be used as a drinking water reservoir.”
Developing contaminate sites can help-
Rebuild cities
Increase tax base
Prevent needless destruction of open space
In some places former Brownfields are being turn into “eco-industrial parks” that have environmentally friendly business and bring jobs to neighborhoods