Hazardous and Radioactive Waste
HAZARDOUS AND RADIOACTIVE WASTE
The most toxic and dangerous waste materials produced in the United States are those classified by the government as hazardous or radioactive.
WHAT IS HAZARDOUS WASTE?
Hazardous waste is dangerous solid waste. The government's definition of solid waste includes materials one would ordinarily consider solid, as well as sludges, semi-solids, liquids, and even containers of gases. The vast majority of hazardous waste is generated by industrial sources. Small amounts come from commercial and residential sources.
Officially, hazardous waste is defined by the federal government as a waste that is either listed as such in regulations issued by the U.S. Environmental Protection Agency (EPA) or that exhibits one or more of the following characteristics: corrosivity, ignitability, reactivity, or contains toxic constituents more than the federal standards. (See Figure 8.1.) In 2007 the EPA had a list of over fifteen hundred hazardous wastes. The list is published in the Code of Federal Regulations (CFR; September 13, 2007, http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?cecfr&tpl%2Findex.tpl) under Title 40 §261.31–33.
Because of its dangerous characteristics, hazardous waste requires special care when being stored, transported, or discarded. Most hazardous wastes are regulated under Subtitle C of the Resource Conservation and Recovery Act (RCRA). The EPA has the primary responsibility for permitting facilities that treat, store, and dispose of hazardous waste. The states can adopt more stringent regulations if they wish.
Contamination of the air, water, and soil with hazardous waste can frequently lead to serious health problems. Exposure to some hazardous wastes is believed to cause cancer, degenerative diseases, mental retardation, birth defects, and chromosomal changes. Even though most scientists agree that exposure to high doses of hazardous waste is dangerous, there is less agreement on the danger of exposure to low doses.
INDUSTRIAL HAZARDOUS WASTE
Industrial hazardous wastes are usually a combination of compounds, one or more of which may be hazardous. For example, used pickling solution from a metal processor may contain acid, a hazardous waste, along with water and other nonhazardous compounds. (Pickling is a chemical method of cleaning metal and removing rust during processing.) A mixture of wastes produced regularly as a result of industrial processes generally consists of diluted rather than full-strength compounds. Often, the hazardous components are suspended or dissolved in a mixture of dirt, oil, or water.
Every two years the EPA, in partnership with the states, publishes the National Biennial RCRA Hazardous Waste Report (http://www.epa.gov/epaoswer/hazwaste/data/br05/national05.pdf). The latest report available was published in December 2006 and includes data from 2005.
The EPA distinguishes between large- and small-quantity generators of hazardous waste. A large-quantity generator is one that:
- Generates at least 1,000 kilograms (2,200 pounds) of RCRA hazardous waste in any single month
- Generates in any single month or accumulates at any time at least 1 kilogram (2.2 pounds) of RCRA acute hazardous waste
- Generates or accumulates at any time at least 100 kilograms (220 pounds) of spill clean-up material contaminated with RCRA acute hazardous waste
In 2005 there were 14,984 large-quantity generators and 1,207 small-quantity generators in the United States.
Together, they generated 38.3 million tons of RCRA hazardous waste. In 2005 the five states with the largest generation of hazardous waste were Texas (15.2 million tons), Louisiana (5.4 million tons), Ohio (2.1 million tons), Mississippi (1.5 million tons), and Kentucky (1.1 million tons). Together, these states accounted for more than two-thirds (66%) of the total quantity generated.
The chemical industry was by far the largest producer, responsible for 21.1 million tons of hazardous waste, or 56% of the total. Petroleum and coal products manufacturers were responsible for 5.1 million tons (13% of the total), followed by the resin, synthetic rubber, and artificial synthetic fibers and filaments manufacturing industry with 1.8 million tons (5% of the total).
METHODS OF MANAGING HAZARDOUS WASTE
Before the 1970s most industrial hazardous waste was dumped in landfills, stored on-site, burned, or discharged into surface waters with little or no treatment. Since the Pollution Prevention Act of 1990, industrial waste management follows a hierarchy introduced by the EPA that advocates source reduction first, followed by recycling or reuse, and then treatment. Source reduction is an activity that prevents the generation of waste initially—for example, a change in operating practices or raw materials. The second choice is recycling, followed by energy recovery. If none of these methods is feasible, then treatment before disposal is recommended.
For example, a paper mill that changes its pulping chemicals might reduce the amount of toxic liquid left over after the paper is produced. If that is not possible, perhaps the pulping liquid could be recycled and reused in the process. If not, perhaps the liquid can be burned for fuel to recover energy. If not, and the liquid requires disposal, it should be treated as necessary to reduce its toxicity before being released into the environment.
A variety of chemical, biological, and thermal processes can be applied to neutralize or destroy toxic compounds in hazardous waste. (See Table 8.1.) For example, microorganisms and chemicals can remove hazardous hydrocarbons from contaminated water. State and federal regulations require the pretreatment of most hazardous wastes before they are discarded in landfills. These treated materials can only be placed in specially designed land disposal facilities. Besides land disposal, hazardous wastes may be injected deep underground under high pressure in wells thousands of feet deep. (See Figure 8.2.) Hazardous waste can also be burned in incinerators. However, as waste is burned, hot gases are released into the atmosphere, carrying toxic materials not consumed by the flames. In 1999 the federal government imposed a ban on new hazardous waste incinerators.
FEDERAL REGULATION OF HAZARDOUS WASTES
The Toxics Release Inventory
The Toxics Release Inventory (TRI) was established under the Emergency Planning and Community Right-to-Know Act of 1986. Under the program certain industrial facilities using specific toxic chemicals must report annually on their waste management activities and toxic chemical releases. These releases are to air, land, or water. More than 650 toxic chemicals are on the TRI list. In addition, the Pollution Prevention Act of 1990 requires the EPA to collect data on toxic chemicals that have been recycled, treated, or combusted for energy recovery.
Manufacturing facilities (called original industries) have had to report under the TRI program since 1987. In 1998 the TRI requirements were extended to a second group of industries called new industries. These include metal and coal mining, electric utilities burning coal or oil, chemical wholesale distributors, petroleum terminals, bulk storage facilities, RCRA Subtitle C hazardous water treatment and disposal facilities, solvent recovery services, and federal facilities. However, only facilities with
|Technologies to neutralize or destroy toxic compounds in hazardous waste|
|SOURCE: Adapted from "Figure III-21. Excerpts from the 40 CFR 268.42 Technology-Based Standards Table," in RCRA Orientation Manual, EPA530-R-02-016, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, January 2003, www.epa.gov/epaoswer/general/orientat/romtoc.pdf (accessed July 27, 2007)|
|Biodegradation||Biodegradation uses microorganisms to breakdown organic compounds to make a wasteless toxic.|
|Chemical reduction||Chemical reduction converts metal and inorganic constituents in wastewater into insoluble precipitates that are later settled out of the wastewater, leaving a lower concentration of metals and inorganics in the wastewater.|
|Combustion||Combustion destroys organic wastes or makes them less hazardous through burning in boilers, industrial furnaces, or incinerators.|
|Deactivation||Deactivation is treatment of a waste to remove the characteristic of ignitability, corrosivity, or reactivity.|
|Macroencapsulation||Macroencapsulation is the application of a surface coating material to seal hazardous constituents in place and prevent them from leaching or escaping.|
|Neutralization||Neutralization makes certain wastes less acidic or certain substances less alkaline.|
|Precipitation||Precipitation removes metal and inorganic solids from liquid wastes to allow the safe disposal of the hazardous solid portion.|
|Recovery of metals||Recovery of organics uses direct physical removal methods to extract metal or inorganic constituents from a waste.|
|Recovery of organics||Recovery of organics uses direct physical removal methods (e.g., distillation, steam stripping) to extract organic constituents from a waste.|
|Stabilization||Stabilization (also referred to as solidification) involves the addition of stabilizing agents (e.g., Portland cement) to a waste to reduce the leachability of metal constituents.|
ten or more full-time employees that use certain thresholds of toxic chemicals are included.
In the 2005 Toxics Release Inventory (TRI) Public Data Release Report (March 2007, http://www.epa.gov/tri/tridata/tri05/pdfs/2005brochure.pdf), the EPA states that 25.1 billion pounds of TRI chemicals were waste managed during 2005. The breakdown by management method is shown in Figure 8.3. Thirty-six percent of the waste was recycled, and 34% was treated. Another 18% was released to the environment, and 12% was used for energy recovery. The EPA reports that 4.3 billion pounds of TRI chemicals were released during 2005 by 23,461 facilities. Most of the chemicals (88%) were released on-site. Figure 8.4 shows the distribution of releases to the environment.
A breakdown by industry is provided in Figure 8.5. The metal mining industry was responsible for more than a quarter (27%) of the releases, followed by electric utilities (25%) and chemicals production (12%). In the 2005 TRI Public Data Release eReport (March 2007, http://www.epa.gov/tri/tridata/tri05/pdfs/eReport.pdf), the EPA notes that the states with the highest releases were Alaska (548.4 million pounds), Nevada (326.1 million pounds),
Ohio (276.9 million pounds), Texas (261.8 million pounds), and Indiana (249.2 million pounds). These five states accounted for more than 38% of all TRI releases in 2005. According to the EPA, total releases of the core set of TRI chemicals (those that were identified and tracked beginning in 1988) declined by 58% (1.7 billion pounds) between 1988 and 2005 from roughly 3 billion pounds to 1.3 billion pounds.
The Resource Conservation and Recovery Act
The RCRA, first enacted by Congress in 1976 and expanded by amendments in 1980, 1984, 1992, and 1996, was designed to manage the disposal, incineration, treatment,
and storage of waste in landfills, surface impoundments, waste piles, tanks, and container storage areas. It regulates the production and disposal of hazardous waste and provides
guidelines and mandates to improve waste disposal practices. The EPA also has the authority under the RCRA to require businesses with hazardous waste operations to take corrective action to clean up the waste they have released into the environment.
The RCRA imposes design and maintenance standards for waste disposal facilities, such as the installation of liners to prevent waste from migrating into ground-water. Land disposal facilities in operation after November 1980 are regulated under the act and are required to meet RCRA standards or close. Owners of facilities that ceased operation before November 1980 are required to clean up any hazardous waste threats their facilities still pose. Abandoned sites and those that owners cannot afford to clean up under the RCRA are usually referred to the national Superfund program.
The Comprehensive Environmental Response, Compensation, and Liability Act and the Superfund
The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980 established the Superfund program to pay for cleaning up highly contaminated hazardous waste sites that had been abandoned or where a sole responsible party could not be identified. Originally a $1.6 billion, five-year program, the Superfund was focused initially on cleaning up leaking dumps that jeopardized groundwater.
During the original mandate of the Superfund, only six sites were cleaned up. When the program expired in 1985, many observers viewed it as a billion-dollar fiasco rampant with scandal and mismanagement. Nonetheless, the negative publicity surrounding the program increased public awareness of the magnitude of the clean-up job in the United States. Consequently, in 1986 and later in 1990 the Superfund was reauthorized.
the national priorities list
the national priorities list. CERCLA requires the government to maintain a list of hazardous waste sites that pose the highest potential threat to human health and the environment. This list is known as the National Priorities List (NPL) and includes hazardous waste sites in the country that are being cleaned up under the Superfund program. The NPL constitutes Appendix B to the National Oil and Hazardous Substances Pollution Contingency Plan, 40 CFR Part 300, which the EPA promulgated pursuant to Section 105 of CERCLA.
The NPL is constantly changing as new sites are officially added (finalized) and other sites are deleted (removed). Table 8.2 shows NPL site actions and milestones achieved by fiscal year (October through September) for 1992 through 2007. These data were reported in June 2007, so only data for nine months are included for fiscal year 2007.
According to the EPA (http://www.epa.gov/superfund/sites/npl/status.htm), as of August 27, 2007, there were 1,242 sites on the NPL. More than one thousand had been declared as "construction completed." The EPA determines construction completed when all physical construction of clean-up actions are completed, all immediate threats have been addressed, and all long-term threats are under control. This does not mean that a site has met its clean-up goals. It simply means that the engineering/construction phase of site clean-up is completed. The EPA has deleted 320 sites from the NPL. Sites are deleted when the EPA determines that "no further federal steps under CERCLA are appropriate." As can be summed from Table 8.2, more sites were proposed to the NPL (406) than were deleted (282) between 1992 and 2007.
According to the EPA, the construction phase of cleanup was completed at more than three times as many Super-fund sites between 1993 and 2000 as in all the previous years of the program combined. (See Figure 8.6.) However, many NPL sites are still years away from having all hazardous waste removed.
funding for superfund
funding for superfund. Funding for the Superfund program is derived through two major sources: the Super-fund Trust Fund and monies appropriated from the federal government's general fund.
The Superfund Trust Fund was set up as part of the original Superfund legislation of 1980. It was designed to help the EPA pay for clean-ups and related program activities. Figure 8.7 shows the Superfund budget history between 1981 and 2005. Until 1995 the Superfund Trust Fund was financed primarily by dedicated taxes collected from companies in the chemical and crude oil industries. This system was extremely unpopular with many corporations arguing that environmentally responsible companies should not have to pay for the mistakes of others. In 1995 the tax was eliminated.
The Superfund Trust Fund is also financed through cost recoveries—money that the EPA recovers through legal settlements with responsible parties. The EPA is authorized to compel parties responsible for creating hazardous pollution, such as waste generators, waste haulers, site owners, or site operators, to clean up the sites. If these parties cannot be found, or if a settlement cannot be reached, the Superfund program finances the clean-up. After completing a clean-up, the EPA can take action against the responsible parties to recover costs and replenish the fund. According to the EPA, in many cases the polluters cannot be located or are unable to pay. In other cases the agency lacks the staff or evidence to proceed with lawsuits.
|National Priorities List (NPL) site actions and milestones, 1992–2007|
|*These totals represent the total number of partial deletions by fiscal year and may include multiple partial deletions at a site. Currently, there are 56 partial deletions at 46 sites.|
|Notes: A fiscal year is October 1 through September 30. Fiscal year 2007 data are from October 1, 2006 through June 28, 2007. Partial deletion totals are not applicable until fiscal year 1996, when the policy was first implemented.|
|SOURCE: "Number of NPL Site Actions and Milestones by Fiscal Year," in National Priorities List, U.S. Environmental Protection Agency, June 28, 2007, http://www.epa.gov/superfund/sites/query/queryhtm/nplfy.htm (accessed June 28, 2007)|
|Sites proposed to the NPL||30||52||36||9||27||20||34||37||40||45||9||14||26||12||10||5|
|Sites finalized on the NPL||0||33||43||31||13||18||17||43||39||29||19||20||11||18||11||5|
|Sites deleted from the NPL||2||12||13||25||34||32||20||23||19||30||17||9||16||18||7||5|
All these factors have resulted in only modest amounts of money being collected for the Superfund Trust Fund through cost recoveries. Total revenue into the fund dropped substantially beginning in 2000. (See Figure 8.7.) However, the EPA has continued to add sites to the NPL that require clean-up.
In recent years the EPA has increasingly relied on money appropriated from the federal government's general fund to pay for NPL clean-ups. During the early 2000s the general fund accounted for roughly half of all appropriations to the Superfund program, as shown in Figure 8.7. The budgets for 2004 and 2005 were based entirely on the general fund. This means that all American taxpayers are assuming the financial burden to clean up hazardous waste sites under the Superfund program. Some critics have called for the federal government to reinstate dedicated taxes against petroleum and chemical corporations to fund the Superfund program, instead of burdening tax-paying individuals.
HAZARDOUS WASTE FROM SMALL BUSINESSES AND HOUSEHOLDS
A small percentage of hazardous waste comes from thousands of small-quantity generators—businesses that produce less than 1,000 kilograms (2,205 pounds) of hazardous waste per month. Common generators are dry-cleaning facilities, furniture-making plants, construction companies, and photo processors. Typical hazardous wastes include spent solvents, leftover chemicals, paints, and unused cleaning chemicals. Hazardous wastes from small-quantity generators and households are regulated under Subtitle D of RCRA.
Household hazardous waste (HHW) includes solvents, paints, cleaners, stains, varnishes, pesticides, motor oil, and car batteries. The EPA reports in "Household Hazardous Waste" (August 9, 2007, http://www.epa.gov/garbage/hhw.htm) that Americans generate 1.6 million tons of household hazardous waste every year. The average home can have as much as 100 pounds of these wastes in basements, garages, and storage buildings. Because of the relatively low amount of hazardous substances in individual products, HHW is not regulated as a hazardous waste. Since the 1980s many communities have held special collection days for household hazardous waste to ensure that it is disposed of properly.
Universal wastes are a federally defined subset of hazardous wastes that are produced in small amounts by
many generators. As of 2007 the federal list of universal wastes includes batteries, pesticides, mercury-containing equipment (e.g., thermostats), and lamps (e.g., fluorescent bulbs). Even though these wastes sometimes wind up in the municipal waste stream, they contain worrisome components, such as heavy metals, that pose an environmental hazard. Thus, the EPA regulates them separately from other hazardous wastes with simpler streamlined requirements designed to encourage generators to recycle or dispose of the wastes properly. The EPA's universal waste regulations are published in 40 CFR 273 and apply only to businesses, not residential generators. The states are allowed to adopt the federal universal waste regulations or add to them, as they see fit. For example, California's list of universal wastes as of June 2007 included nonempty aerosol cans, batteries (excluding automotive), cell phones, electronic devices (computers, monitors, televisions, etc.), and mercury-containing items, such as fluorescent lamps.
focus on electronic waste
focus on electronic waste. Improper disposal of electronic goods poses environmental risks because of the presence of hazardous metals and other contaminants in the products, as noted in Table 8.3. Concern about the environmental hazards of electronic waste disposal has prompted action by state governments around the country. These measures are discussed by Denise Griffin of the National Conference of State Legislatures, in "Electronic Waste" (July 2005, http://www.ncsl.org/programs/environ/cleanup/elecwaste.htm). Griffin describes legislation crafted in Arkansas, California, Maine, Maryland, and Virginia. Overall, California and Maine have incorporated the strictest regulatory actions designed to achieve maximum recycling results.
In 2003 California passed legislation called the Electronic Waste Recycling Act. This act requires electronic manufacturers to reduce the amount of hazardous substances used in specific electronic products sold in California. It also established a funding mechanism to ensure that these products are properly collected and recycled at the end of their useful lives. In 2005 retailers began collecting fees from consumers purchasing certain electronic products (primarily monitors and other display products with cathode ray tubes). The fees range from $6 to $10 per item, depending on the size of the item. The
|Contaminants of concern in old electronics|
|SOURCE: Adapted from "What Are the Contaminants of Concern in Old Electronics and What Are Their Pathways?" in eCycling: Frequent Questions, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, April 18, 2006, http://www.epa.gov/epaoswer/hazwaste/recycle/ecycling/faq.htm (accessed June 20, 2007)|
|Cadmium||Chip resistors, infrared detectors, and semiconductors||Cadmium can accumulate in, and negatively impact, the kidneys. Cadmium is persistent, bioaccumulative, and toxic. The principal exposure pathway is through respiration and through our food.|
|Lead||Glass panels in computer monitors and in lead soldering of printed circuit boards||Lead can cause damage to the central and peripheral nervous systems, blood systems, and kidneys in humans. Lead has also been shown to have negative effects on the development of children's brains. Lead can accumulate in the environment and have a detrimental effect on plants, animals, and humans. Consumer electronics may be responsible for 40% of the lead found in landfills. The principal pathway of concern is lead leaching from landfills and contaminating drinking water supplies.|
|Mercury||Thermostats, position sensors, relays and switches (e.g., on printed circuit boards), discharge lamps, batteries, medical equipment, data transmission, telecommunications, and mobile phones.||When mercury makes its way into waterways, it is transformed into methylated mercury in the sediments. Methylated mercury accumulates in living organisms and travels up the food chain. Methylated mercury can cause brain damage. The principal exposure pathway is through our food.|
|Hexavalent chromium (chromium VI)||Used to protect against corrosion of untreated and galvanized steel plates||Chromium VI can damage DNA and has been linked to asthmatic bronchitis. The major pathways are through landfill leachate or from fly ash generated when materials containing Chromium VI are incinerated.|
|Brominated flame retardants||Printed circuit boards, components such as plastic covers and cables as well as plastic covers of televisions||Although less is known about BFRs than some other contaminants of concern, but research has shown that one of these flame retardants, polybrominated diphenylethers (PDBE) might act and an endocrine disrupter. Flame retardant polybrominated biphenyls (PBB) may increase cancer risk to the of the digestive and lymph systems. Once released into the environment through landfill leachate and incineration they are concentrated in the food chain.|
money is turned over to the state and distributed to qualified companies engaged in collecting and recycling the products.
In 2004 California passed the Cell Phone Recycling Act, which forbids retailers from selling cell phones unless they have a collection, reuse, and recycling program in place for them. The recycling programs must not charge a fee to consumers. The act went into effect in July 2006.
What Is Radioactivity?
Radioactivity is the spontaneous emission of energy and/or high-energy particles from the nucleus of an unstable atom. The three primary types of radiation are alpha, beta, and gamma. Isotopes are atoms of an element that have the same number of protons but different numbers of neutrons in their nuclei. For example, the element carbon has twelve protons and twelve neutrons comprising its nucleus. One isotope of carbon, C-14, has twelve protons and fourteen neutrons in its nucleus. This is a radioactive isotope or radioisotope.
Radioisotopes are unstable and their nuclei decay, or break apart, at a steady rate. Decaying radioisotopes produce other isotopes as they emit energy and/or high-energy particles. If the newly formed nuclei are radioactive too, they emit radiation and change into other nuclei. The final products in this chain are stable, non-radioactive nuclei. The amount of time it takes for half the radioactive nuclei in a sample to decay is called the half-life. Half-lives range from a fraction of a second to many thousands of years, depending on the substance.
Radioactivity is measured in units called curies. One curie represents the quantity of radioactive material that will undergo thirty-seven billion disintegrations per second. The biological effect of radiation on human tissue is defined using a unit called the roentgen equivalent man or rem. A rem is the dosage of ionizing radiation that will cause the same biological effect as one roentgen of x-ray or gamma radiation.
Radioisotopes reach our bodies daily, emitted from sources in outer space, and from rocks and soil on Earth. Radioisotopes are also used in medicine and provide useful diagnostic tools.
Energy can be released by artificially breaking apart atomic nuclei. Such a process is called nuclear fission. The fission of uranium 235 (U-235) releases several neutrons that can penetrate other U-235 nuclei. In this way the fission of a single U-235 atom can begin a cascading chain of nuclear reactions. If this series of reactions is regulated to occur slowly, as it is in nuclear power plants, the energy emitted can be captured for a variety of uses, such as generating electricity. If this series of reactions is allowed to occur all at once, as in a nuclear (atomic) bomb, the energy emitted is explosive. (Plutonium-239 can also be used to generate a chain reaction similar to that of U-235.)
Sources of Radioactive Waste
Radioactive waste results from the mining, processing, and use of radioactive materials for commercial, military, medical, and research purposes. In general, the U.S. Department of Energy (DOE) is responsible for managing radioactive waste associated with the nation's military and defense operations. The Nuclear Regulatory Commission (NRC) has primary responsibility for managing radioactive wastes produced by other sources. Some state agencies have also been authorized to regulate aspects of radioactive waste management within their jurisdictions. The EPA regulates the release of radioactive materials to the environment.
nuclear power plants
nuclear power plants. The primary commercial source of radioactive waste is associated with electricity generation at nuclear power plants. These plants rely on controlled slow fission reactions with nuclear fuel pellets to produce heat to create steam. Figure 8.8 shows the locations of operational nuclear power reactors in the United States as of 2005. At that time just over one hundred reactors were operating at more than sixty facilities. According to the DOE's Energy Information Administration, in "Generation" (May 16, 2003, http://www.eia.doe.gov/cneaf/electricity/epav1/generation.html#N_39_), nuclear power has accounted for approximately 18% to 20% of power generation in the United States since the 1990s.
No new nuclear power plants have been ordered since the late 1970s. The decline is attributed to a variety of factors including construction and regulatory difficulties, availability of cheap supplies of natural gas, and public opposition to nuclear power. Opposition grew dramatically following an emergency at the Three Mile Island nuclear power plant near Harrisburg, Pennsylvania. On March 28, 1979, equipment failures, design problems, and operator errors led to a partial meltdown in the nuclear core of one of the reactors. A meltdown occurs when cooling of the nuclear fuel rods is inadequate and the fuel overheats and melts, releasing radioactivity to the atmosphere.
Even though no one was directly injured or killed by the accident, it did expose a substantial population of nearby residents to radioactive gases. The NRC indicates in the fact sheet "Three Mile Island Accident" (February 20, 2007, http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/3mile-isle.pdf) that approximately two million people in the area were exposed to an average dose of one millirem. This is roughly one-sixth the amount of radiation associated with a full set of chest x-rays.
Public fears about nuclear power were rekindled in 1986, when an explosion occurred at a nuclear power plant near the town of Chernobyl in the Soviet Union (now Ukraine). In the early morning hours of April 26, 1986, operators decided to test one of the reactors to see what would happen if the station lost electrical power. A combination of design flaws and operator errors during the test resulted in a massive power surge that overheated and ruptured some of the fuel rods. The resulting explosions destroyed the nuclear reactor core and ripped the roof off the reactor building, sending radioactive debris and smoke into the atmosphere.
Dozens of people, mostly plant workers, died during the explosion or soon thereafter of acute radiation poisoning. Hundreds, possibly thousands, more people died later as a result of exposure to radiation released by the accident. More than one hundred thousand people were evacuated from nearby areas. The Chernobyl disaster left a long-lasting negative public perception about nuclear power.
military and defense sources
military and defense sources. The U.S. government maintained an active program for nuclear weapons development from the early 1940s through the 1980s. As scientists raced to develop an atomic bomb during World War II (1939–1945), wartime concern for national security led to a "culture of secrecy" that became characteristic of agencies dealing with nuclear power. On July 16, 1945, the first bomb was exploded above ground in Alamogordo, New Mexico. A few weeks later, two nuclear bombs were dropped on Japan. World War II ended and the Cold War began.
The Atomic Energy Act of 1946 put the responsibility for nuclear weapons development and production under the authority of a new agency called the Atomic Energy Commission (AEC). The AEC developed a nationwide complex of facilities that engaged in research, manufacturing, and testing of nuclear weapons. In 1975 the AEC was abolished, and the DOE assumed responsibility for atomic energy activities.
During the first three decades following the development of the atomic bomb, nuclear waste management received little attention from government policy makers. Beginning in the 1970s public concern about the environmental and health risks of stockpiled nuclear materials led to political action. Over the next decade nuclear weapons production was curtailed. When the Soviet Union collapsed in 1991, the DOE ceased nearly all production of new nuclear weapons. In addition, a major undertaking began to dismantle and destroy many of the nuclear weapons that had been created.
In 1989 the DOE formed a new program that was eventually directed by the Office of Environmental Management to oversee the massive and expensive effort to clean up over one hundred former nuclear weapons facilities. The U.S. Government Accountability Office estimates in Nuclear Waste: Better Performance Reporting Needed to Assess DOE's Ability to Achieve the Goals of the Accelerated Cleanup Program (July 2005, http://www.gao.gov/new.items/d05764.pdf) that the DOE spent more than $60 billion on environmental management between 1989 and 2001. Another $192 billion in spending was projected to complete the clean-up effort. Spending outlays by the DOE for environmental management are reported each year for the previous fiscal year in the president's annual Budget of the United States Government. The DOE notes in Budget of the United States Government, Fiscal Year 2008 (2007, http://www.whitehouse.gov/omb/budget/fy2008/energy.html) that an estimated $6 billion was spent on environmental management in fiscal year 2007. Summing actual spending from the budgets for previous fiscal years shows that, between 2001 and 2007, more than $40 billion was spent. This brings the total spent on environmental management between 1989 and 2007 to approximately $100 billion.
The DOE notes in Five-Year Plan: FY 2007–FY 2011 (March 15, 2006, http://www.science.doe.gov/Budget_and_Planning/Five-Year%20Plan/FYP%20Vol%20I%20-%20final%20version.pdf) that for fiscal years 2008 through 2011 an average of $6.9 billion is expected to be requested each year for environmental management. In Cleaning up the Nuclear Weapons Complex: Internet Resources (March 30, 2001, http://www.rff.org/nuclearcleanup/), Resources for the Future, an environmental research organization, states that the majority of the program costs will be devoted to facilities in Savannah River, South Carolina; Hanford, Washington; Idaho Falls, Idaho; and Oak Ridge, Tennessee.
Classes of Radioactive Waste
Federal and state agencies classify radioactive wastes based on their radioactivity, sources, and methods of management. These classifications differ from agency to agency, and there is sometimes overlap between classes. Major classes defined by the federal government include uranium mill tailings, high-level radioactive wastes, low-level radioactive wastes, and transuranic waste. (See Table 8.4.)
uranium mill tailings
uranium mill tailings. Uranium mining was extensively practiced in the western United States in the decades following World War II. This resulted in the
|Primary categories of nuclear waste|
|SOURCE: Adapted from "Table 1. Primary Categories of Environmental Waste and Byproducts," in 2006 Environmental Liabilities: Long-Term Fiscal Planning Hampered by Control Weaknesses and Uncertainties in the Federal Government's Estimates, U.S. Government Accountability Office, March 2006, http://www.gao.gov/new.items/d06427.pdf (accessed June 19, 2007)|
|Uranium mill tailings||Byproducts and residues resulting from the processing of natural ores to extract uranium and thorium. Tailings are usually in the form of fine sand particles. These wastes contain radium, which has a half-life of thousands of years and decays to produce radon gas. Tailings emit low levels of radiation for long periods of time.|
|Spent nuclear fuel||Fuel elements and irradiated targets that have been removed from nuclear reactors. These spent fuels are highly radioactive and must be stored in special facilities that shield and cool the materials.|
|High-level waste||Highly radioactive byproduct associated with use and reprocessing of nuclear fuel in nuclear reactors. Sources include commercial reactors producing electricity and reactors operated at government and university research institutions and on nuclear-powered submarines and ships. This designation is also applied to solids made when liquid high-level waste is treated. This waste typically contains highly radioactive, short-lived fission products as well as long-lived isotopes, hazardous chemicals, and toxic heavy metals. High-level waste must be isolated from the environment for thousands of years.|
|Transuranic waste||Transuranic elements are radioactive elements with an atomic number (number of protons) greater than that of uranium (ninety-two) and therefore beyond ("trans-") uranium ("-uranic") on the periodic chart of the elements. The vast majority of transuranic elements does not exist in nature, but are synthesized (created) during the production of nuclear weapons. Plutonium is an example of a transuranic element. Transuranic waste is contaminated with transuranic elements at a concentration higher than 100 nanocuries per gram. This includes soil and chemicals as well as contaminated tools, equipment, and clothing. Transuranic waste is generated during nuclear weapons production and other activities involving long-lived transuranic elements, such as plutonium. Some of these isotopes have half-lives of tens of thousands of years, thus requiring long-term isolation.|
|Low-level waste||Any radioactive waste that does not fall into one of the above categories regardless of content, activity level, or longevity. Most low-level waste contains small amounts of radioactivity in large volumes of material. Examples include contaminated items such as protective clothing and shoe covers, tools and equipment, discarded reactor parts and filters, rags, mops, reactor water treatment residues, luminous dials, laboratory and medical supplies, and animal carcasses used in radiation research.|
generation of large amounts of mill tailings. In 1978 Congress passed the Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978 to regulate mill-tailing operations. The law established programs for the cleanup of abandoned mill sites, primarily at federal expense, although owners of still-active mines were financially responsible for their own clean-up.
By the 1980s the United States imported most of the uranium it needed for nuclear power and weapons production. As a result, the vast majority of domestic uranium mines and processing facilities ceased operating.
Under UMTRCA Title I the DOE is responsible for cleaning up abandoned mill-tailings sites that were associated primarily with nuclear weapons production. The NRC oversees the clean-up operations to ensure that they meet environmental standards set by the EPA. Title I is funded jointly by federal and state sources. According to the fact sheet "Uranium Mill Tailings" (April 9, 2007, http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/mill-tailings.pdf), the NRC states that Title I reclamation was ongoing at nineteen tailings disposal sites in 2006. These piles range in size from approximately 60,000 to 4.6 million cubic yards of material. Nearly all the inactive sites are located in western states.
Title II of UMTRCA applies to uranium mill sites licensed by the NRC or by approved state agencies since 1978. The NRC notes in "Uranium Mill Tailings" that sixteen sites fell under this program as of 2006. The vast majority of the sites were inactive and had completed or were completing clean-up activities.
high-level radioactive waste
high-level radioactive waste. High-level radioactive wastes (HLW) associated with the nation's defense operations are generally managed by the DOE. Other sources of HLW fall under NRC jurisdiction. The NRC manages two major types of HLW. The first type is spent reactor fuel from commercial reactors that is ready for disposal. Spent fuel, the used uranium that has been removed from a nuclear reactor, is far from being completely spent. It contains highly penetrating and toxic radioactivity and requires isolation from living things for thousands of years.
As of 2007 no permanent long-term storage facility existed for HLW; therefore, it was stored on-site at the locations where it was generated or transported to other approved sites for temporary storage. Figure 8.9 shows a map of the dozens of sites around the country at which HLW was being temporarily stored in 2005.
According to the NRC, in "Transportation of Spent Nuclear Fuel" (July 3, 2007, http://www.nrc.gov/waste/spent-fuel-transp.html), thousands of shipments of spent nuclear fuel have taken place in the United States since the early 1970s. Utility companies that operate multiple reactors are permitted to transport spent fuel between their facilities. In addition, spent fuel can be transported to research laboratories for testing purposes. Transportation of spent nuclear fuel is regulated by the NRC and the U.S. Department of Transportation.
High-level radioactive waste also results when spent fuel is reprocessed. This is a chemical process in which radioactive isotopes, primarily uranium and plutonium, are extracted from spent fuel for reuse as reactor fuel. As of 2007 there were no reprocessing operations in the United States devoted to commercial nuclear fuel.
During the Cold War the DOE reprocessed spent nuclear fuel at several locations for defense purposes. In 1992 the agency discontinued the program because of lack of demand for the fuel. As a result, significant amounts of
spent nuclear fuel remain in storage at some DOE facilities. The DOE reports in "National Spent Nuclear Fuel Program" (July 24, 2007, http://nsnfp.inel.gov/snfData.asp) that as of December 2006 it maintained more than twenty-four hundred containers of spent nuclear fuel at locations around the country, including the Hanford Site in Washington State, and the Idaho National Laboratory in Idaho Falls, Idaho.
The Office of Civilian Radioactive Waste Management (OCRWM) is in charge of developing and managing a federal system for the disposal of spent nuclear fuel from commercial nuclear reactors and high-level radioactive waste from national defense activities.
low-level radioactive waste
low-level radioactive waste. Until the 1960s the United States dumped low-level radioactive wastes (LLW) into the ocean. The first commercial site to house such waste was opened in 1962, and by 1971 six sites were licensed for disposal. The volume of LLW increased until the Low-Level Radioactive Waste Policy Act of 1980 and its amendments in 1985. In "Low-Level Waste Disposal Statistics" (March 21, 2007, http://www.nrc.gov/waste/llw-disposal/statistics.html), the NRC reports that in 2005 LLW disposal totaled 4 million cubic feet.
According to the NRC, in "Locations of Low-Level Waste Disposal Facilities" (April 5, 2007, http://www.nrc.gov/waste/llw-disposal/locations.html), there were only three commercial low-level waste sites still operating in 2007. Facilities in Richland, Washington, and Barnwell, South Carolina, accept a broad range of LLW, whereas a facility in Clive, Utah, operates a disposal site that accepts some types of LLW as well as other non-HLW wastes.
In 1980 Congress called for the establishment of a national system of LLW disposal facilities under the Low-Level Radioactive Waste Policy Act. Every state became responsible for finding a low-level disposal site for wastes generated within its borders by 1986. The act encouraged states to organize themselves into compacts to develop new radioactive waste facilities. In "Low-Level Waste Compacts" (March 21, 2007, http://www.nrc.gov/waste/llw-disposal/compacts.html), the NRC notes that as of 2007 there were eleven compacts that encompassed forty states.
No compact or state has, however, successfully developed a new disposal facility for LLW. Compacts and unaffiliated states have confronted significant barriers to developing disposal sites, including public health and environmental concerns, antinuclear sentiment, substantial financial requirements, political issues, and "not in my backyard" campaigns by citizen activists.
transuranic waste. Transuranic wastes are those with an atomic number greater than that of uranium (92) and therefore beyond ("trans-") uranium. Until 1999 all transuranic wastes were in temporary storage at various DOE facilities around the country. Because transuranic waste contains isotopes with half-lives that reach into the tens of thousands of years, the DOE had to develop a permanent storage plan. In 1999 it began moving the wastes to a storage facility in southern New Mexico called the Waste Isolation Pilot Plant (WIPP).
Geologic Repositories for Radioactive Waste
The United States has been working for decades to establish permanent storage facilities for high-level radioactive waste and transuranic waste. Historically, these wastes have been kept in temporary storage at nuclear power plants and DOE facilities around the country. Permanent storage sites are geological repositories, that is, storage facilities constructed deep underground in ancient geological formations that are relatively dry and not subject to earthquakes or other stresses.
Engineers working on permanent storage facilities have designed barrier systems that combine multiple physical barriers with chemical controls to provide a high level of long-term containment for radioactive waste. Radioactive waste is chemically treated for long-term storage and placed into steel drums. The drums are then placed in a concrete container. Many of these drum-filled concrete containers, surrounded with a special chemically treated backfill material, are placed in a larger concrete container deep in the ground. The rock surrounding this large concrete container must have low groundwater flow. The multiple barriers, chemical conditions, and geologic conditions under which the wastes are stored ensure that the wastes dissolve slowly and pose little danger to the groundwater. The Waste Isolation Pilot Plant in southeastern New Mexico has begun processing transuranic (defense) waste and, when it opens, the proposed Yucca Mountain facility in Nevada will process waste from nuclear power plants.
the waste isolation pilot plant
the waste isolation pilot plant. The Waste Isolation Pilot Plant became the world's first deep depository for nuclear waste when it received its first shipment in March 1999. The large facility is located in a desert region near Carlsbad, New Mexico. It was designed for permanent storage of the nation's transuranic waste. WIPP is 2,150 feet below the surface in the salt beds of the Salado Formation. The layout is depicted in Figure 8.10.
According to WIPP (September 10, 2007, http://www.wipp.energy.gov/shipments.htm), 50,345 cubic meters (1.8 million cubic feet) of transuranic waste had been deposited at the facility by September 2007. Over six thousand shipments had been received at that time, most from Idaho National Laboratory and the Rocky Flats Environmental Technology Site (Colorado). The total amount of transuranic waste that can be deposited at WIPP is capped by the Waste Isolation Pilot Plant Land Withdrawal Act (1992) at 175,570 cubic meters (6.2 million cubic feet).
As transuranic waste is transported to WIPP, it is tracked by satellite and moved at night when traffic is light. It can be transported only in good weather and must be routed around major cities.
Every five years the DOE must submit to the EPA a recertification application that documents WIPP's compliance with radioactive waste disposal regulations. The DOE (http://www.wipp.energy.gov/library/CRA/index.htm) submitted the first such application in March 2004.
yucca mountain. The centerpiece of the federal government's geologic disposal plan for spent nuclear fuel and other high-level waste is the Yucca Mountain site in Nevada. The site is approximately one hundred miles northwest of Las Vegas on federal lands within the Nevada Test Site in Nye County. As shown in Figure 8.11, the mountain is located in a remote desert region.
The Nuclear Waste Policy Act of 1982 required the secretary of energy to investigate the site and, if it was suitable, to recommend to the president that the site be established. In February 2002 President George W. Bush (1946–) received such a recommendation and approved it. Despite opposition from Nevada's governor, the project was subsequently approved by the U.S. House of Representatives and the U.S. Senate. In July 2002 President Bush signed the Yucca Mountain resolution into law.
The DOE must next submit a license application to the NRC to receive permission to begin construction. The DOE must satisfactorily demonstrate that the combination of the site and the repository design complies with standards set forth by the EPA for containing radioactivity within the repository. The DOE (April 30, 2007, http://www.ocrwm.doe.gov/ym_repository/license/index.shtml) reported in 2007 that the application was being prepared and was scheduled to be submitted in mid-2008. In addition, the Yucca site was anticipated to open in 2017.
Development of the Yucca Mountain repository has been plagued by legal setbacks and political controversy. Nevada lawmakers have waged a massive and often successful campaign to stop the project from proceeding. Their ultimate goal is to stifle it completely.
As part of the licensing effort, the DOE is required to develop a massive electronic database that is available to the public and that includes all DOE documents supporting the license application. The Licensing Support Network (http://www.lsnnet.gov/) is expected to contain millions of pages when it is completed.