Hazardous Waste

Introduction

Human activities create a continuous waste stream, amounting to around 600 million metric tons in the United States alone each year. Some of this waste material may present a hazard to either human health or to the environment. It may pose a fire risk, or be toxic. Waste of all kinds is dealt with by disposal, destruction, or recycling. Dumping it is no longer considered acceptable and poses the highest risk where hazardous waste is concerned.

Many countries have environmental legislation dealing with hazardous waste. Generally this requires those generating these wastes to keep track of them and prevent them from emerging into the public domain. There are many sites that were contaminated before legislation was put in place and present an ongoing hazard. Governments often have measures in place to force clean up of these locations. Meanwhile, alternative approaches to make industrial processes less hazardous are becoming increasingly popular.

Historical Background and Scientific Foundations

The U.S. Environmental Protection Agency (EPA) defines hazardous wastes as materials that are dangerous or potentially harmful to human health or the environment. The EPA further describes a hazardous waste as one that is ignitable, corrosive, reactive, or toxic. Some materials possess more than one of these properties. There are at least 265 million metric tons of hazardous waste produced in the United States every year. The petrochemical, chemical, metal, and mining industries are responsible for the majority of this waste, but it can also be generated by municipal sources in the form of cleaning materials, car oil, personal medical waste, and garden pesticides.

Hazardous waste comes from a wide variety of sources. It may consist of by products of industrial processes or discarded commercial products and could be in the form of solid, liquid, or gas. The EPA deals with this diversity by setting out lists of hazardous wastes in three different categories. The F-list refers to non-specific source wastes, coming from common manufacturing and industrial processes. A typical example of an F-list waste would be solvents used in degreasing operations.

The K-list covers wastes from specific industries, such as pesticide manufacturing or petroleum refining and refers to items such as wastewater or sludges that they would typically produce. The P-list and U-list include discarded commercial chemical products that can pose a hazard, such as pesticides or pharmaceuticals.

Impacts and Issues

Hazardous waste causes the most problems when it is merely dumped with no attempt to treat or contain it. This practice can be harmful in many ways. For instance, children may expose themselves to infection by playing with syringes in abandoned medical waste. Meanwhile, oil and other toxic chemicals can seep into groundwater and contaminate the water supply, maybe for many years to come. Vast as the oceans are, dumping here rather than on land is not the answer to the hazardous waste problem. Millions of bottles, tins, plastic containers, and fishing nets, among other things, are in the oceans. They may seem harmless in themselves, although unsightly, but when marine animals such as dolphins and seals become entangled in them and thereby drown or starve, then this waste also becomes hazardous.

WORDS TO KNOW

BIOREMEDIATION: The use of living organisms to help repair damage such as that caused by oil spills.

BROWNFIELD SITE: A site contaminated with hazardous waste.

GREEN CHEMISTRY: An approach to chemical manufacturing that reduces its negative impact on the environment.

Dumping is illegal in many industrialized nations. To get around this, some companies took to exporting hazardous waste to developing countries that were often ill equipped to deal with it. Most countries banned this practice in 1989, but it continues. In 2006, for example, 400 tons of petroleum waste were dumped in Abidjan, the capital of the Ivory Coast, killing ten people and producing severe symptoms among at least 100,000 others.

A growing problem is the export and dumping of so-called electronic waste in the form of old computers, cell phones, and television sets. The electronic components of these gadgets contain toxic heavy metals including nickel, mercury, and lead, as well as valuable metals like gold, silver, and copper. Around 80% of this waste is shipped to China and other countries in Asia and Africa where people, including young children, break them up to retrieve precious metals, often without the necessary protective gear. Exposure to these metals is particularly hazardous for children whose brain and nervous systems are still developing. Soil and water in the areas where electronic waste is processed are found to have levels of heavy metals far in excess of World Health Organization limits.

The most important step in dealing with hazardous waste is to identify it and keep it separate from other forms of waste. Thereafter, it may be stored or disposed of, recycled, or converted into a harmless form. The method of choice will depend on the exact nature of the waste and the hazard it poses.

Many countries have now put in place legislation to protect their populations and environment from the effects of hazardous waste. In the United States, the Resource, Conservation & Recovery Act was introduced in 1976, and it requires those who generate, ship, use, and dispose of hazardous waste to account for its treatment from “cradle to grave.” This lifecycle approach to managing hazardous waste is intended to minimize the risk it poses.

Hazardous waste can pose a threat for many years, and there is a legacy of contamination dating from before legislation was introduced. Brownfield sites are places where industries or facilities generating hazardous waste were once located. People are often reluctant to build on or otherwise develop Brownfield sites in case local populations are then affected by health problems. A famous example is Love Canal in Niagara Falls, New York, where more than 20,000 tons of toxic chemical waste were buried under what was to later become a housing development. Local residents noted a high incidence of miscarriage and birth defects and campaigned to link these to the presence of the waste. Eventually, President Jimmy Carter declared a national emergency at the site and had the residents relocated and compensated. There is an ongoing study into their health.

The United States introduced the Comprehensive Environmental Response, Compensation and Liability Act, also known as the Superfund Act, in 1980, following the Love Canal incident. This legislation deals with the treatment and liability for these contaminated sites, the most seriously polluted of which are designated as Superfund sites. The level of cleanup obviously depends on the use intended for the land. There are various new technologies for remediation of such land. For instance, bioremediation uses microbes or plants to convert or absorb toxic materials. Aquatic plants like water hyacinth have been used in this way, and there are many species of bacteria that can render long-lasting toxic wastes such as polychlorinated biphenyls harmless by breaking them down.

Both industry and the general population can make a contribution to reducing the amount of hazardous waste in circulation. The chemical industry is investing in so-called green chemistry, where they look for chemical reactions that can be carried out in an aqueous, rather than organic, solvent, thereby reducing the amount of flammable and toxic waste. People can opt for less hazardous household chemicals for cleaning and pest control. They should also be sure to dispose of metals in batteries and old electronic equipment as advised by local environmental authorities.

Primary Source Connection

The catastrophe of Love Canal described in the article that follows exemplifies the dangers of unrestricted dumping of hazardous waste.

Love Canal is symbolic of the havoc that unregulated chemical disposal can cause. Although much suffering and death came from Love Canal, the disaster did galvanize opposition to the unregulated environmental disposal of dangerous compounds. In the wake of Love Canal, the U.S. Congress enacted the Superfund legislation holding polluters accountable for cleanup of high-priority sites. Under the Superfund program, over 10,000 toxic dumpsites have been identified across the United States.

THE LOVE CANAL TRAGEDY

Quite simply, Love Canal is one of the most appalling environmental tragedies in American history.

But that’s not the most disturbing fact.

What is worse is that it cannot be regarded as an isolated event. It could happen again—anywhere in this country—unless we move expeditiously to prevent it.

It is a cruel irony that Love Canal was originally meant to be a dream community. That vision belonged to the man for whom the three-block tract of land on the eastern edge of Niagara Falls, New York, was named—William T. Love.

Love felt that by digging a short canal between the upper and lower Niagara Rivers, power could be generated cheaply to fuel the industry and homes of his would-be model city.

But despite considerable backing, Love’s project was unable to endure the one-two punch of fluctuations in the economy and Louis Tesla’s discovery of how to economically transmit electricity over great distances by means of an alternating current.

By 1910, the dream was shattered. All that was left to commemorate Love’s hope was a partial ditch where construction of the canal had begun.

In the 1920s the seeds of a genuine nightmare were planted. The canal was turned into a municipal and industrial chemical dumpsite.

Landfills can of course be an environmentally acceptable method of hazardous waste disposal, assuming they are properly sited, managed, and regulated. Love Canal will always remain a perfect historical example of how not to run such an operation.

In 1953, the Hooker Chemical Company, then the owners and operators of the property, covered the canal with earth and sold it to the city for one dollar.

It was a bad buy.

In the late 1950s, about 100 homes and a school were built at the site. Perhaps it wasn’t William T. Love’s model city, but it was a solid, working-class community. For a while.

On the first day of August, 1978, the lead paragraph of a front-page story in the New York Times read:

NIAGARA FALLS, N.Y.—Twenty five years after the Hooker Chemical Company stopped using the Love Canal here as an industrial dump, 82 different compounds, 11 of them suspected carcinogens, have been percolating upward through the soil, their drum containers rotting and leaching their contents into the backyards and basements of 100 homes and a public school built on the banks of the canal.

In an article prepared for the February, 1978 EPA Journal, I wrote, regarding chemical dumpsites in general, that “even though some of these landfills have been closed down, they may stand like ticking time bombs.” Just months later, Love Canal exploded.

The explosion was triggered by a record amount of rainfall. Shortly thereafter, the leaching began.

I visited the canal area at that time. Corroding waste-disposal drums could be seen breaking up through the grounds of backyards. Trees and gardens were turning black and dying. One entire swimming pool had been popped up from its foundation, afloat now on a small sea of chemicals. Puddles of noxious substances were pointed out to me by the residents. Some of these puddles were in their yards, some were in their basements, others yet were on the school grounds. Everywhere the air had a faint, choking smell. Children returned from play with burns on their hands and faces.

And then there were the birth defects. The New York State Health Department is continuing an investigation into a disturbingly high rate of miscarriages, along with five birth-defect cases detected thus far in the area.

I recall talking with the father of one the children with birth defects. “I heard someone from the press saying that there were only five cases of birth defects here,” he told me. “When you go back to your people at EPA, please don’t use the phrase ‘only five cases.’ People must realize that this is a tiny community. Five birth defect cases here is terrifying.”

A large percentage of people in Love Canal are also being closely observed because of detected high white-blood-cell counts, a possible precursor of leukemia. When the citizens of Love Canal were finally evacuated from their homes and their neighborhood, pregnant women and infants were deliberately among the first to be taken out.

“We knew they put chemicals into the canal and filled it over,” said one woman, a long-time resident of the Canal area, “but we had no idea the chemicals would invade our homes. We’re worried sick about the grandchildren and their children.”

Two of this woman’s four grandchildren have birth defects. The children were born and raised in the Love Canal community. A granddaughter was born deaf with a cleft palate, an extra row of teeth, and slight retardation. A grandson was born with an eye defect.

Of the chemicals which comprise the brew seeping through the ground and into homes at Love Canal, one of the most prevalent is benzene—a known human carcinogen, and one detected in high concentrations. But the residents characterize things more simply.

“I’ve got this slop everywhere,” said another man who lives at Love Canal. His daughter also suffers from a congenital defect.

On August 7, New York Governor Hugh Carey announced to the residents of the Canal that the State Government would purchase the homes affected by chemicals. On that same day, President Carter approved emergency financial aid for the Love Canal area (the first emergency funds ever to be approved for something other than a “natural” disaster), and the U.S. Senate approved a “sense of Congress” amendment saying that Federal aid should be forthcoming to relieve the serious environmental disaster which had occurred.

By the month’s end, 98 families had already been evacuated. Another 46 had found temporary housing. Soon after, all families would be gone from the most contaminated areas—a total of 221 families have moved or agreed to be moved.

State figures show more than 200 purchase offers for homes have been made, totaling nearly $7 million.

A plan is being set in motion now to implement technical procedures designed to meet the seemingly impossible job of detoxifying the Canal area. The plan calls for a trench system to drain chemicals from the Canal. It is a difficult procedure, and we are keeping our fingers crossed that it will yield some degree of success.

I have been very pleased with the high degree of cooperation in this case among local, State, and Federal governments, and with the swiftness by which the Congress and the President have acted to make funds available.

But this is not really where the story ends. Quite the contrary.

We suspect that there are hundreds of such chemical dumpsites across this Nation. Unlike Love Canal, few are situated so close to human settlements. But without a doubt, many of these old dumpsites are time bombs with burning fuses—their contents slowly leaching out. And the next victim cold be a water supply, or a sensitive wetland. The presence of various types of toxic substances in our environment has become increasingly widespread—a fact that President Carter has called “one of the grimmest discoveries of the modern era.”

Chemical sales in the United States now exceed a mind-boggling $112 billion per year, with as many as 70,000 chemical substances in commerce.

Love Canal can now be added to a growing list of environmental disasters involving toxics, ranging from industrial workers stricken by nervous disorders and cancers to the discovery of toxic materials in the milk of nursing mothers.

Eckardt C. Beck

BECK, ECKARDT C. “THE LOVE CANAL TRAGEDY.” EPA JOURNAL (JANUARY 1979).

See Also Chemical Spills; Electronics Waste; Industrial Pollution; Medical Waste; Superfund site; Toxic Waste; Waste Transfer and Dumping

BIBLIOGRAPHY

Books

Cunningham, W.P., and A. Cunningham. Environmental Science: A Global Concern. New York: McGraw-Hill International Edition, 2008.

Web Sites

U.S. Environmental Protection Agency. “The Love Canal Tragedy: EPA History.” January 1979. http://www.epa.gov/history/topics/lovecanal/01.htm (accessed March 17, 2008).

Susan Aldridge

Hazardous Waste

The Resource Conservation and Recovery Act (RCRA), enacted in 1976, defines hazardous waste as a liquid, solid, sludge, or containerized gas waste substance that due to its quantity, concentration, or chemical properties may cause significant threats to human health or the environment if managed improperly. U.S. legislation considers a waste hazardous if it is corrosive, flammable, unstable, or toxic. Sources of hazardous waste may include industry, research, medical, household, chemical producers, agriculture, and mining, as well as many others.

Most hazardous waste comes from industrial sources. The EPA specifies four different categories of hazardous waste that are subject to regulation: hazardous wastes from nonspecific sources involved in industrial processes such as spent halogenated solvents; hazardous wastes from specific industrial sources, such as untreated wastewater from the production of the herbicide 2,4-dichlorophenoxyacetic acid (2,4,-d); commercial chemical products that may be discarded (such as benzene) used in the manufacture of drugs, detergents, lubricants, dyes and pesticides; and wastes that are classified as toxic, such as vinyl chloride. Hazardous waste from many industrial processes include solvents such as methylene chloride, a probable carcinogen that is commonly used in paint removers. Trichloroethylene, a solvent that has been found in groundwater is monitored and regulated in drinking water in the United States. Drinking or breathing high levels of trichloroethylene can lead to damage of the liver, lung, and nervous system. In many industries the sludge remaining after treatment of wastewater accounts for much of the generated hazardous waste. Sludges and wastewater from electroplating operations commonly contain cadmium, copper, lead, and nickel. These heavy metals are found in the sediment of Lake Huron and have been associated with degradation of benthos and planktonic communities. Heavy metals can impact the health of humans and wildlife in a variety of ways: lead interferes with the nervous system and can lead to learning disabilities in children and cadmium accumulates in humans and animals and can lead to kidney disfunction. Household products that contain hazardous ingredients are not regulated under RCRA but should be disposed of separately from municipal garbage following label instructions. Household hazardous waste (HHW) can include used motor oil, paint thinners and removers, wood preservers, batteries, fluorescent lights that contain mercury, and unused pesticides.

The U.S. Environmental Protection Agency (EPA) and state regulatory agencies collect information about the generation, management, and final disposal of hazardous wastes regulated under RCRA. This report gives detailed data on hazardous waste generation and waste management practices for treatment, storage, and disposal facilities.

Waste Minimization and Recycling

Recycling and waste minimization may be the best ways to deal with hazardous waste. Waste minimization reduces the volume of waste generated, whereas recycling means that less hazardous waste requires disposal. Techniques for waste minimization may include audits, better inventory management, production process/equipment modifications, and operational/maintenance procedures. Raw material changes, volume reductions, nonhazardous material substitutions, reuse, or recovery also reduce hazardous waste production. For example biodegradable, nontoxic lactate esters are solvents manufactured from renewable carbohydrate sources that can be substituted for toxic halogenated solvents.

The EPA's Industrial Toxics Project is a nonregulatory program initiated in 1990 to achieve, voluntarily, overall reductions for seventeen toxic chemicals reported in the government's Toxics Release Inventory (TRI), including cadmium, lead, mercury, trichloroethylene, and toluene. The recycling of waste through waste exchanges is one aspect of industrial ecology and another way to address the issue of hazardous waste disposal. For example the sludge that accumulates in scrubbers removing sulfur dioxide from power plant smokestacks contains calcium sulfate, which can be recycled in wallboard. Waste exchange also promotes the use of one company's waste as another company's raw material. Waste exchanges typically list both available and desired materials. Several regional waste exchanges exist, as well as exchanges within small geographic regions. Some exchanges charge for their services, whereas others are supported by grants.

Disposal Options and Problems

Disposal options for hazardous waste include landfills, injection wells , incineration, and bioremediation , as well as several others. The greatest concern with the disposal of hazardous waste in landfills or injection wells is that toxic substances will leak into surrounding groundwater. Groundwater is a major source of drinking water worldwide and once it is contaminated, pollutants are extremely difficult and costly to remove. In some instances, it is impossible to remove groundwater contamination. The ideal disposal method is the destruction and conversion of hazardous waste to a non-hazardous form. New technology for hazardous and mixed low-level radioactive waste conversion includes a high-temperature plasma torch that converts low-level radioactive wastes to environmentally safe glass. Conversion to environmentally safe substances can be very expensive for some types of hazardous wastes and technically impossible for others, creating the need for alternative disposal methods.

The most common form of hazardous waste disposal in the United States is landfilling. Hazardous waste landfills are highly regulated and are required to include clay liners, monitoring wells, and groundwater barriers. The 1984 Hazardous Solid Waste Amendments require the monitoring of groundwater near landfills for thirty years. Injection wells may be used to inject hazardous waste deep into the earth, but problems result with aquifer contamination and the ultimate fate of the hazardous waste after injection is unknown.

Incineration may be an effective way to convert hazardous waste into a nonhazardous form while greatly decreasing its volume. The waste is burned and converted into carbon dioxide, water, and inorganic by-products. The problems associated with incineration are high capital and operating costs, and the disposal of ash, which may contain hazardous substances. In addition, incinerating wastes can cause mercury and dioxin air pollution. Bioremediation may also be used in situ or ex situ to convert hazardous wastes to nontoxic by-products using microorganisms and natural degradation processes. Biodegradation requires very long treatment times and it may be difficult to control or enhance natural degradation processes. Phytoremediation, the process by which plants absorb and in some cases degrade hazardous substances in the environment, is being investigated as an emerging cleanup technology. For example poplar trees have been shown to break down the herbicide atrazine, mustard plants will remove lead from soil, and the alpine pennycress plant will take large amounts of heavy metals and also uranium from soil.

When hazardous waste is to be transported off-site for disposal, the waste generator prepares a shipping document called a manifest. This form must accompany the waste to its final destination and is used to track the waste's movements from "cradle to grave."

Hazardous Waste Production in the United States

Facilities that produce hazardous waste, usually as a result of an industrial process, are considered large-quantity generators (LQG) or small-quantity generators (SQG) depending on the quantities produced. Hazardous waste may be transported to alternate locations to be treated, stored, or disposed of, or may be managed at the place of generation.

In 1995, 20,873 LQGs produced 214 million tons of hazardous waste regulated by RCRA. There were 3,489 fewer LQGs and a reduction of 44 million tons of waste by 1995 compared to 1993. The five states generating the largest amount of hazardous waste were Texas (69 million tons), Tennessee (39 million tons), Louisiana (17 million tons), Michigan (13 million tons), and Illinois (13 million tons), accounting for 70 percent of the national totals.

The industrial trade of hazardous waste has become an extensive problem. Many third world countries accept large volumes of hazardous waste for disposal in return for sizable financial compensation. Unfortunately, the large profits reaped by such poor countries do not compensate for the long-term environmental impacts from improperly managed hazardous waste. Many wastes have also been dumped illegally on international shores where environmental regulation and controls are often lacking.

see also Abatement; Brownfield; Cleanup; Green Chemistry; Incineration; Industrial Ecology; Injection Well; Landfill; Medical Waste; Radioactive Waste; Resource Conservation and Recovery Act; Waste, Transportation of.

Bibliography

Davis, Mackenzie L., and Cornwell, David A. (1998). Introduction to Environmental Engineering. Boston: McGraw-Hill.

Graedel, T.E., and Allenby, B.R. (1995). Industrial Ecology. Upper Saddle River, NJ: Prentice Hall.

La Grega, Michael D.; Buckingham, Philip L.; Evans, Jeffrey C.; and Environmental Resources Management. (2001). Hazardous Waste Management. Boston: McGraw-Hill.

Vesiland, P. Aarne; Worrell, William; and Reinhart, Debra. (2002). Solid Waste Engineering. Australia: Brooks/Cole.

Watts, Richard J. (1998). Hazardous Wastes: Sources, Pathways, Receptors. New York: John Wiley & Sons.

Margrit von Braun and Deena Lilya

Hazardous waste

Of the thousands of millions of tons of waste generated in the United States annually, approximately 60 million tons are classified as hazardous. Hazardous waste is legally defined by the Resource Conservation and Recovery Act (RCRA) of 1976. The RCRA defines hazardous waste as any waste or combination of wastes, which because of its quantity, concentration, or physical,chemical, or infectious characteristics may: A) cause, or significantly contribute to, an increase in mortality or an increase in serious irreversible or incapacitating illness; or, B) pose a substantial present or potential hazard to human health or the environment when improperly treated, stored, transported, disposed of, or otherwise managed.

In the Code of Federal Regulations, the Environmental Protection Agency (EPA) specifies that a solid waste is hazardous if it meets any of four conditions: 1) It exhibits ignitability corrosivity, reactivity, or EP toxicity; 2) has been listed as a hazardous waste; 3) is a mixture containing a listed hazardous waste and a nonhazardous waste, unless the mixture is specifically excluded or no longer exhibits any of the four characteristics of hazardous waste; 4) is not specifically excluded from regulation as a hazardous waste.

The EPA established two criteria for selecting the characteristics given above. The first criterion is that the characteristic is capable of being defined in terms of physical, chemical, or other properties. The second criterion is that the properties defining the characteristic must be measurable by standardized and available test procedures. For example under the term ignitability (Hazard code label "I"), any one of four criteria can be met: 1) A liquid with a flash point less than 60°F (16°C); 2) If not a liquid, then it is capable under standard temperature and pressure of causing fire through friction, absorption of moisture, or spontaneous chemical changes, and when ignited, burns so vigorously and persistently that it creates a hazard; 3) It may be an ignitable compressed gas; 4) It is an oxidizer.

Similarly under the characteristics of corrosivity, reactivity, and toxicity, there are specifically defined requirements which are spelled out in the Code of Federal Register (CFR). Further examples are given below:

• Corrosivity (Hazard code "C") has either of the following properties: an aqueous waste with a pH equal to or less than 2.0 or greater than 12.5; or a liquid which will corrode carbon steel at a rate greater than 0.25 in (0.64 cm) per year.
• Reactivity (Hazard code "R") has at least one of the following properties: a substance which is normally unstable and undergoes violent physical and/or chemical change without being detonated; a substance which reacts violently with water (for example, sodium metal); a substance which forms a potentially explosive mixture when mixed with water; a substance which can generate harmful gases, vapors, or fumes when mixed with water; a cyanide- or sulfide-bearing waste which can generate harmful gases, vapors, or fumes when exposed to pH conditions between 2 and 12.5; a waste which, when subjected to a strong initiating source or when heated in confinement, will detonate and/or generate an explosive reaction; a substance which is readily capable of detonation at standard temperature and pressure.
• Toxicity (Hazard code "E") has the properties such that an aqueous extract contains contamination in excess of that allowed (e.g., arsenic >5 mg/l; barium 0.100 mg/l; cadmium >1 mg/l; chromium >5 mg/l; lead >5 mg/l). Additional codes under toxicity include an "acute hazardous waste" with code "H": a substance which has been found to be fatal to humans in low doses or has been found to be fatal in corresponding human concentrations in laboratory animals. Toxic waste (hazard code "T") designates wastes which have been found through laboratory studies to be a carcinogen , mutagen ,or teratogen for humans or other life forms.

Certain wastes are specifically excluded from classification as hazardous wastes under RCRA, including domestic sewage, irrigation return flows, household waste , and nuclear waste. The latter is controlled via other legislation. The impetus for this effort at legislation and classification comes from several notable cases such as Love Canal , New York; Bhopal, India ; Stringfellow Acid Pits (Glen Avon, California); and Seveso, Italy ; which have brought media and public attention to the need for identification and classification of dangerous substances, their effects on health and the environment, and the importance of having knowledge about the potential risk associated with various wastes.

A notable feature of the legislation is its attempt at defining terms so that professionals in the field and government officials will share the same vocabulary. For example, the difference between "toxic" and "hazardous" has been established; the former denotes the capacity of a substance to produce injury and the latter denotes the probability that injury will result from the use of (or contact with) a substance.

The RCRA legislation on hazardous waste is targeted toward larger generators of hazardous waste rather than small operations. The small generator is one who generates less than 2,205 lb (1,000 kg) per month; accumulates less than 2,205 lb (1,000 kg); produces wastes which contain no more than 2.2 lb (1 kg) of acutely hazardous waste; has containers no larger than 5.3 gal (20 l) or contained in liners less than 22 lb (10 kg) of weight of acutely hazardous waste; has no greater than 220 lb (100 kg) of residue or soil contaminated from a spill, etc. The purpose of this exclusion is to enable the system of regulations to concentrate on the most egregious and sizeable of the entities that contribute to hazardous waste and thus provide the public with the maximum protection within the resources of the regulatory and legal systems.

[Malcolm T. Hepworth ]

RESOURCES

BOOKS

Dawson, G. W., and B. W. Mercer. Hazardous Waste Management. New York: Wiley, 1986.

Dominguez, G. S., and K. G. Bartlett. Hazardous Waste Management. Vol. 1, The Law of Toxics and Toxic Substances. Boca Raton: CRC Press, 1986.

U.S. Environmental Protection Agency. Hazardous Waste Management: A Guide to the Regulations. Washington, DC: U.S. Government Printing Office, 1980.

Wentz, C. A. Hazardous Waste Management. New York: McGraw-Hill, 1989.

HAZARDOUS WASTE

HAZARDOUS WASTE is a by-product, usually of manufacturing, medical and scientific research, and consumer detritus (disintegrating materials), that is dangerous to human health and wildlife. The substances defined as hazardous received their initial analysis in the industrial hygiene movement between 1900 and 1930, which focused on substances in the workplace. The movement's concern with hazardous industrial substances seldom extended beyond the factory walls. Although public health authorities in the late nineteenth century considered industrial pollution a major problem, the focus shifted after the acceptance of the germ theory of disease. Public health officers and sanitary engineers focused on bacterial wastes as the primary threat to human health. When they considered industrial wastes, they concentrated on their non-pathogenic effects. It was only after World War II that professionals began to pay greater attention to health and the environment.

The first federal legislation regarding hazardous waste was the 1970 Solid Waste Disposal Act. Section 212 required that the Environmental Protection Agency (EPA) investigate the storage and disposal of hazardous wastes. The resulting 1974 report to Congress on the disposal of hazardous wastes led to the passage in 1976 of the Resource Conservation and Recovery Act (RCRA), which defined hazardous wastes that can cause illness or pose a hazard to health and to the environment when improperly stored, transported, or managed. In 1980, the EPA announced regulations implementing cradle-to-grave controls for handling hazardous wastes.

RCRA did not touch on the dangers of wastes buried in industrial and municipal landfills. For decades, industries had disposed of hazardous materials in landfills. Land disposal of wastes increased in the post-World War II period, as states put limits on water disposal. These older sites, in many cases abandoned or closed, posed a threat to groundwater supplies. The case of Love Canal, a chemical waste dump formed by the Hooker Chemical and Plastics Corporation in Niagara Falls, New York, and from which toxic chemical wastes migrated to endanger neighboring residential areas, focused public and govern-mental attention on the problem in the late 1970s.

Congress responded to the perceived danger of these sites in 1980 by approving the Comprehensive Environ-mental Response, Compensation, and Liability Act (CERCLA), or Superfund, which provided $1.6 billion for the cleanup of toxic wastes. Under CERCLA, the EPA established procedures of site-specific risk assessments to determine whether the hazardous wastes were a threat to human health. The Superfund Amendments and Reauthorization Act in 1986 increased the fund to $9.6 billion. The Superfund Act and its amendments sought to cover the costs of cleanup by requiring retrospective liability. That is, it made those people and companies responsible for creating hazardous waste sites liable for the costs of cleanup. The amendments also required that firms that imported, processed, or produced more than 50,000 pounds per year of any of the EPA's listed chemicals and compounds, register them in the EPA's annual Toxics Release Inventory. The slow pace of cleanups, however, as well as cumbersome procedures, convinced many experts that Superfund was not only underfunded but imposed unreasonable standards of cleanliness, given future site uses.

One of Superfund's main tools was a trust fund that contained money contributed by corporations that were taxed to help pay for cleanup operations at Superfund sites. In 1995, that legislation expired. In the following years, Democratic President Bill Clinton annually attempted to renew the legislation, but the Republican-controlled legislature consistently blocked his efforts. Once Republican President George W. Bush came into office, the White House ceased to agitate for renewal. Many critics see the Superfund program as fundamentally flawed because it spends too much money in court battles to determine who is responsible for cleaning up hazardous sites. Furthermore, they argue that taxing the chemical and petrochemical industries to clean up sites that they did not pollute is unfair. In 2001, $860 million was available for Superfund cleanup, but that amount was projected to fall to $28 million by 2003.

BIBLIOGRAPHY

Anderson, Terry L., ed. Political Environmentalism: Going Behind the Green Curtain. Stanford, CA: Hoover Institution Press, 2000.

Barnett, Harold C. Toxic Debts and the Superfund Dilemma. Chapel Hill: University of North Carolina Press, 1994.

Hird, John A. Superfund: The Political Economy of Environmental Risk. Baltimore: Johns Hopkins University Press, 1994.

Mazur, Allan. A Hazardous Inquiry: The Rashomon Effect at Love Canal. Cambridge, Mass: Harvard University Press, 1998.

Switzer, Jacqueline Vaughn. Environmental Politics: Domestic and Global Dimensions. New York: St. Martin's Press, 1994; 1998.

Joel A.Tarr/a. e.

See alsoEnergy, Department of ; Energy Industry ; Environ-mental Business ; Environmental Protection Agency ; Times Beach ; Waste Disposal ; Water Pollution .

HAZARDOUS WASTE

All human activities generate some form of waste. In its most general sense, the term "hazardous waste" comprises toxic chemicals, radioactive materials, and biologic or infectious waste. Hazardous waste poses a threat to workers through occupational exposure and to the public through exposure in homes, communities, and the general environment. Exposure may occur near the site of generation, along transportation corridors, and near the ultimate disposal sites. Most hazardous waste results from industrial processes that yield unwanted intermediates, products that fail quality control, and spilled material.

Hazardous waste management is divided into two main areas: currently generated waste, which is regulated under the Resource Conservation and Recovery Act (RCRA) of 1976, and waste at abandoned sites, which is regulated under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980. The Environmental Protection Agency (EPA) has jurisdiction and responsibility for managing the "cleanup" of hazardous waste sites. The Agency for Toxic Substances and Disease Registry (ATSDR), a branch of the Centers for Disease Control and Prevention (CDC), evaluates and assists communities that have been exposed to hazardous waste.

Under RCRA, industries assume responsibility for all of the waste they generate. They may manage it on-site or ship it off-site. In the latter case they retain responsibility, even when it has reached a legal disposal site. This is termed "cradle-to-grave" responsibility. Under CERCLA (also known as the Superfund Act), states may petition the EPA to have a hazardous waste site listed on the National Priorities List. This makes the site eligible for federal cleanup assistance in the event that a responsible party is not identified or does not accept responsibility.

Under RCRA, solid waste is defined as hazardous if its "quantity, concentration, or physical, chemical, or infectious characteristic" leads to death or serious illness or otherwise poses a "substantial present or potential hazard to human health or the environment, when improperly treated, stored, transported, or disposed of, or otherwise mismanaged." Under the Toxic Substances Control Act, more than 55,000 individual chemicals can fit the definition of a hazardous waste.

The main types of hazardous wastes are depleted raw materials, reaction products, tank residues, filter cake, precipitates, and spent solvents. They may be disposed of in liquid or solid form, either contained or uncontained. Wastes must be listed on a manifest, hauled by a licensed hauler, and disposed of at an approved hazardous waste site.

It is estimated that hazardous chemical wastes have been stored at more than 50,000 sites in the United States alone, although only 1,500 are listed on the National Priorities, or Superfund, List. To be listed, a site must be assessed using the EPA Hazard Ranking System. Once the site is identified, a preliminary site assessment is performed to determine if there is a potential hazard. If a hazard exists, there may be emergency remediation, but typically the second phase is a remedial investigation/feasibility study that categorizes a site and identifies remediation options. Remediation may range from an enclosure and warning signs to complete removal of waste, capping, and treatment of groundwater.

The Hazard Ranking System yields three scores, involving: (1) the possibility of offsite migration; (2) the likelihood of human receptors coming in contact with contaminated air, water, soil, or organisms; and (3) the explosivity or fire hazard posed by the material.

The ten substances most often identified at Superfund sites are: trichloroethylene, toluene, benzene, lead, chloroform, polychlorinated biphenyls (PCBs), tetrachloroethylene, phenol, trichloroethane, and chromium. The receptor populations include not only neighbors living adjacent to industrial sources or waste sites, but emergency responders, public safety officials, regulatory agency personnel, and hazardous-waste remediation workers.

Pathways of exposure include: direct contact with contaminated soil from playing or working on or adjacent to a waste site, consumption of contaminated groundwater, inhalation of vapors or dust from a site, and consumption of contaminated food stuffs.

Michael Gochfeld

(see also: Agency for Toxic Substances and Disease Registry; Benzene; Environmental Determinants of Health; Environmental Protection Agency; Hazardous Waste; Landfills, Sanitary; Lead; Municipal Solid Waste; Nuclear Waste; Occupational Safety and Health; PCBs; Pollution; Toxic Substances Control Act; Toxicology )

Bibliography

Gochfeld, M. (1995). "Hazardous Waste." In Textbook of Occupational and Environmental Medicine, eds. L. Rosenstock and M. Cullen. Philadelphia, PA: W. B. Saunders.

Gochfeld, M., and Burger, J. (1995). "Assessment and Mediation of Hazardous Waste Sites." In Environmental Medicine, ed. S. Brooks et al. St. Louis, MO: Mosby.