AEC. Abbreviation for the U.S. Atomic Energy Commission. AEC was disbanded in 1974, and its functions were assumed by the Energy Research and Development Administration (ERDA) and the Nuclear Regulatory Commission (NRC). ERDA later became part of the Department of Energy (DOE).

alpha particle. A positively charged particle, consisting of two neutrons and two protons, emitted by certain radioactive materials. Alpha particles can travel only a few inches in the air and lose their energy almost as soon as they collide with anything. They are easily shielded by a sheet of paper or the outer layer of a person’s skin. Contact-handled transuranic (CH-TRU) waste primarily emits alpha particles.

atom. The smallest part of an element that still has all properties of that element. Its nucleus consists of protons and neutrons and is surrounded by orbiting electrons.

beta particle. A negatively charged particle, emitted by certain radioactive materials. Beta particles have the same properties (mass and charge) as electrons. They can travel in the air for a distance of a few feet and can pass through a sheet of paper. They can be shielded by aluminum foil or glass.

CAO. Carlsbad Area Office. In 1993, DOE created the Carlsbad Area Office to lead its transuranic waste disposal efforts. CAO coordinates DOE’s transuranic program at waste-generating sites and national laboratories.

certification of compliance. EPA must grant a certification of compliance indicating that the WIPP has complied with the agency’s disposal standards for transuranic wastes before the WIPP can open.

contact-handled transuranic waste (CH-TRU). Transuranic waste with a surface radiation dose rate that does not exceed 200 millirems per hour. Contact-handled transuranic waste can be safely handled without any shielding other than that provided by the waste container itself. About 97 percent by volume of the waste scheduled to go to the WIPP is considered contact-handled.

cosmic rays. A stream of ionizing radiation (chiefly of protons, alpha particles, and other atomic nuclei).

curie. A measure of radioactivity. One curie of radioactive material will have 37 billion transformations of atoms (disintegrations) in one second. One curie of radium weighs approximately one gram.

defense-generated transuranic waste. Transuranic waste resulting from weapons research and development, the operation of naval reactors, the production of weapons material, the reprocessing of defense spent fuel, and the decommissioning of nuclear- powered ships and submarines.

disposal. Permanent isolation of transuranic waste from the accessible environment with no intent of recovery; occurs when the WIPP repository is backfilled and sealed.

DOE. Abbreviation for the United States Department of Energy. WIPP is a DOE facility.

DOT. Abbreviation for the United States Department of Transportation. DOT regulates the transport of radioactive materials.

element. A substance composed of atoms with a unique number of protons in each nucleus. There are 92 naturally occurring and 15 manmade elements.

environmental impact statement. A document that describes the potential environmental impacts of a project. The National Environmental Policy Act (NEPA) mandates that all federal agencies and departments consider potential environmental impacts before beginning projects or implementing rules and regulations. DOE must finalize its environmental impact statement for the WIPP before the facility can open.

EPA. Abbreviation for the United States Environmental Protection Agency. EPA has responsibility for ensuring DOE’s compliance with the radioactive waste disposal regulations.

gamma rays. Waves of pure energy, similar to x-rays. Gamma rays travel at the speed of light through air or open spaces. Concrete, lead, or steel will block gamma rays.

genetic damage. A type of cellular damage that can result from ionizing radiation. Genetic damage refers to the alteration or mutation of reproductive cells, resulting in potential damage to future generations.

half-life. Measure of the amount of time it takes for half the radioactive atoms in an element to decay to a more stable form. The half-life of plutonium-239, for example, is about 24,000 years. After one half-life, half the radioactive atoms in a sample remain radioactive; after two half-lives, one quarter remain radioactive; after three half lives, one-eighth remain radioactive; and so on. Half-lives range from a fraction of a second to billions of years.

HALFPACK. A prototype of a new transuranic waste transport container that has been developed; an application for certification of the container is pending before NRC.

hazardous waste. A solid waste, or combination of solid wastes, which because of its quantity, concentration, or physical, chemical, or infectious characteristics may (1) cause, or significantly contribute to, an increase in mortality or an increase in serious irreversible, or incapacitating reversible serious, illness or (2) pose a substantial present or potential hazard to human health or the environment when improperly treated, stored, transported, or disposed of, or otherwise managed.

high-level waste. Highly radioactive material resulting from the reprocessing of spent nuclear fuel, or other highly radioactive material that is determined to require permanent isolation.

ionizing radiation. Radiation that is powerful enough to alter atoms by removing one or more electrons, leaving positively charged particles. Alpha and beta particles, gamma rays and x-rays are forms of ionizing radiation.

isotopes. Different forms of the same element. Isotopes of an element have different numbers of neutrons in the nuclei of their atoms, but the same number of protons. Some isotopes, called radioisotopes, are unstable and emit radiation.

low-level waste. Radioactive waste that consists of contaminated industrial or research waste. Most low-level waste is short-lived and has low levels of radioactivity.

mixed waste. Waste which contains both radioactive contamination and hazardous constituents defined under RCRA.

NAS. Abbreviation for the National Academy of Sciences.

NMED. Abbreviation for the New Mexico Environment Department.

nonionizing radiation. Includes visible light, ultraviolet light, infrared light, and radio waves.

NRC. Abbreviation for the Nuclear Regulatory Commission.

Rad (radiation absorbed dose). The amount of ionizing radiation absorbed by a material, such as human tissue.

radiation. Energy in the form of high-speed particles (ionizing) or electromagnetic waves (nonionizing).

radioactivity. The spontaneous emission of radiation from the nucleus of an atom. Radioisotopes of elements lose particles and energy through the process of radioactive decay.

radioisotope. An unstable isotope of an element undergoes radioactive decay toward a more stable form.

radionuclide. A radioactive atomic nucleus.

radon. A cancer-causing gas produced by the breakdown of uranium in soil, rock, and water.

RCRA. Abbreviation for the Resource Conservation and Recovery Act (RCRA).

remote-handled transuranic waste (RH-TRU). Transuranic waste with a surface dose rate of 200 millirems per hour or greater. Because of its higher level of radioactivity, remote-handled transuranic waste must be handled and transported in shielded casks.

rem (Roentgen equivalent man). A measure of the actual biological effects of radiation absorbed in human tissue. A millirem is one-thousandth of a rem.

somatic damage. A type of cellular damage that can result from exposure to ionizing radiation. Somatic damage refers to the alteration of ordinary, nonreproductive cells. Cancers, including some leukemias and bone, thyroid, breast, skin, and lung cancer, are the most common type of somatic damage resulting from exposure to ionizing radiation.

spent nuclear fuel. Irradiated fuel from a nuclear plant’s reactor. Spent nuclear fuel is thermally hot and highly radioactive. Spent fuel is not authorized to be shipped to the WIPP.

STEP. Acronym for DOE’s States Tribal Education Program. The program offers courses on responding to potential incidents involving shipments of waste to the WIPP.

TRANSCOM. Abbreviation for the Transportation Tracking and Communication System developed by DOE. TRANSCOM tracks and communicates with vehicles transporting radioactive and certain other types of hazardous waste. All shipments to WIPP are to be tracked through TRANSCOM, which has a 24-hour control center in Oak Ridge, Tennessee, and uses satellite communications and computer networks to track shipments from beginning to end.

transuranic (TRU) waste. Waste that generally consists of protective clothing, tools, glassware, equipment, soils, and sludge that have been contaminated with manmade radioactive elements heavier than uranium on the periodic table of elements. These elements include plutonium, neptunium, americium, curium, and californium. Transuranic waste is produced during nuclear fuel assembly and during nuclear weapons research, production, and cleanup.

TRUPACT II. Abbreviation for Transportation Packaging Transporter Model 2, a special container constructed to hold contact-handled transuranic waste. The container is designed to prevent radioactive releases, even in the event of an accident or other emergency.

uranium mill tailings. Waste from the mining and milling of uranium ore.

WIPP. Abbreviation for the Waste Isolation Pilot Plant, a DOE facility located in southeastern New Mexico.

WIPP Land Withdrawal Act. A law, passed by Congress in October 1992 and amended in September 1996. The act transferred the land occupied by the WIPP to DOE and gave EPA regulatory responsibility for determining whether the facility complies with radioactive waste disposal standards.