APES Study Guide

Hazardous and Solid Waste

Mrs. Ashley

Waste is usually categorized as: Municipal solid waste (MSW), Hazardous Waste and Nonhazardous industrial waste. Garbage is the solid waste we produce directly. 98% of the world’s solid waste is from mines, factories, food growers, and businesses. 1.5% is municipal waste. Mining, oil and gas production is responsible for 75% of solid waste production in the U.S. U. S. has 4.6% of world’s population and produces 1/3 of the solid waste.

Much of the increase in MSW in the U.S. has grown due to excessive packaging and the use of disposable materials. One of the problems with disposal is that people throw away things with the attitude that they are gone forever (out of sight, out of mind).

U.S disposal is at this rate: 54.8% in landfills, 17% combustion, and 28% recycling

Composition of solid waste: 38% paper, 12% yard waste, 10% plastics, 10% food wastes, 7.6% metals, 7% rubber, 5.7% glass, %.4% wood, 3% other.

Open dumps More common in developing countries

Landfills: problems include: groundwater contamination, methane production, incomplete decomposition, and settling. Modern landfills are situated on high ground well above the water table; the floor is covered with plastic and contoured so that the water will drain into a leachate collection system. Above the plastic is compacted soil and porous gravel layer. The leached water is then collected and prevented from getting into the water table. The refuse is layered forming a mountain in a pyramid shape. The entire site is monitored by ground water monitoring wells.

As old landfills close, it becomes difficult to find locations for new landfills.

Combustion: Can reduce the weight of trash by over 70%. The ash must still be disposed of. Most modern combustion facilities generate electricity; some of the ash is recovered and can be reused in the formation of cinder blocks.

Disadvantages: Health effects, expensive to build, hazardous materials must be disposed of properly, may impede recycling.

Solutions: Waste management and waste reduction (refuse, reduce, reuse, or recycle)

Reuse means cleaning and reusing materials over and over. (returning soda bottles are an example. Stop making things that are throw away. Disposable diapers, Problems with e-waste

Source reduction

Recycling is reprocessing discarded solid material into new useful products. Primary recycling is taking something and reprocessing it into something very similar (newspapers to recycled paper). Secondary recycling or downcycling is taking a product and making something new out of the materials (used tired become part of a road).

Recycling: Paper (41.6% recovery); glass (25.5 recovery); plastic (5.4% recovery); metals (aluminum, 28% recovery saves up to 90% of the energy required to make aluminum from virgin ore); yard wastes 45.3% recovery; textiles (12.8% recovery); old tires (22% recovery)

Composting is a form of recycling of biodegradable wastes

Materials recovery facility (MRF) sorts mixed wastes for recycling, are expensive

Source separation approach –people separate materials at home. Pay-as-you-throw (PAUT) charges households for the amount of mixed wastes, but not for separated wastes.

Recycling plastics is difficult because it is hard to separate them and costs more to separate than to make new plastics

Why we don’t have more recycling and reuse:

§  market price of products do not include the price of harmful environmental health costs,

§  resource extracting companies receive more government tax breaks,

§  charges for depositing wastes are too low,

Product stewardship is required in E U. E waste is handled more efficiently in E.U.

Solutions as the sustainability six:

Consume less

Redesign industry to use less material and energy

Redesign industry to produce less waste and pollution.

Develop products that are easy to repair, reuse, remanufacture, compost or recycle

Design products to last longer

Eliminate or reduce unnecessary packaging

Ecoindustrial revolution—sell services instead of things. Change from a material flow economy to a service flow economy.

Hazardous waste:

These are waste products of homes, factories, businesses, military operations, and other facilities that pose a threat to people and the environment. They are toxic, carcinogenic or mutagenic. Heavy metals: lead, mercury, arsenic cadmium, tin chromium, zinc and copper.

Lead is a neurotoxin with no safe level in children.

Mercury: Found in high levels in some fish Used widely in industry, medicines and pesticides, paint pigments, batteries and electronics.

Dioxin: many forms are carcinogens. Are a by product of industrial processes and burning of municipal and medical wastes

The Resource Conservation and Recovery Act (RCRA) The following are not regulated by RCRA: Radioactive wastes, household wastes, mining wastes, oil and gas drilling, liquid waste with hydrocarbon compounds, from small businesses. Hazardous wastes- 72% of chemical and petroleum industry and 22% of mining industry.

Love Canal was an example of an area affected by hazardous waste. Love Canal near Niagara Falls, NY was to be a canal that was never finished. Instead the Hoover Chemical Company in 1946 went into an agreement with the canal’s owners to dump hazardous wastes into the abandoned canal. Extremely hazardous wastes were dumped including dioxin. The area was sold to Niagara Falls and a school was built on the site. The dump was covered with topsoil and clay once thought to be sufficient. This helped in creating the Superfund law—polluters are responsible for cleaning up the sites. (CERCLA of 1980)

Largest industrial accident occurred in Bhopal India in 1984 due to lack of updating and following safety.

Organic compounds: toxic because readily absorbed into the body. Halogens (PVCs, pesticides, solvents, )

Methods of dealing with Hazardous Wastes:

Physical methods—filtering out solids, distilling liquid mixtures, encapsulating and storing in deep underground wells or in drums. Some placed above ground in containment buildings. Each year there are 500,000 shipments of hazardous wastes

Chemical methods—use of cyclodextrin to soak up toxic substances

Biological methods—plants (phyto-remediation); bacteria and enzymes(bioremediation)

Plasma—use of heat to detoxify wastes

Burning

POP Treaty of 2001-to control 12 persistent organic pollutants (called the dirty dozen)