CHAPTER 21: SOLID, TOXIC AND HAZARDOUS WASTE

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

OPEN DUMP

“Smokey

mountain” in

Manila,

Philippines where

20,000 people

live and work

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

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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