A glossary of terms
Compiled
by John Lemons
Daily Record News Group
The
nuclear industry uses a language all its own. Some of it will be
familiar from high school chemistry classes, but other acronyms
and definitions are like a foreign language to people who do not
work in the industry. Here are some of the terms and phrases that
readers might find in this series of stories.
Glossary
ALARA
- As Low As Reasonably Achievable, or keeping radiation emissions
and exposures to levels set as far below regulatory limits as is
reasonably possible in order to protect public health and the environment.
Alpha
radiation - The most energetic but least penetrating form of radiation.
It can be stopped by a sheet of paper and cannot penetrate human
skin. However, if an alpha-emitting isotope is inhaled or ingested,
it will cause highly concentrated local damage.
Aquifer
- A permeable body of rock capable of yielding quantities of groundwater
to wells and springs.
AR
- Administrative Record, a required, comprehensive file of documents
that forms the basis of decisions made regarding cleanup.
ARARs
- Applicable or relevant and appropriate requirements, a comprehensive
set of laws and regulations that are relevant to guide the selection
of cleanup activity at a particular site.
Atom
- The smallest particle of an element having the chemical properties
of that element; the fundamental building block of matter.
Background
radiation - The natural radioactivity in the environment. Natural
radiation consists of cosmic rays, filtered through the atmosphere
from outer space, and radiation from the naturally radioactive elements
in the earth (primarily uranium, thorium, radium and potassium).
Also known as natural radiation.
Beta
radiation - High-energy electrons (beta particles) emitted from
certain radioactive material. Can pass through 1 to 2 centimeters
of water or human flesh and can be shielded by a thin sheet of aluminum.
Beta particles are more deeply penetrating than alpha particles
but, because of their smaller size, cause less localized damage.
BDN
- Biodenitrification, the process of breaking down nitrates into
harmless elements through the use of living bacteria.
Biological
effects - The early or delayed results of biological damages caused
by nuclear radiation (alpha, beta gamma).
Biosphere
- The part of the earth and its atmosphere in which living things
exist.
BRA
- Baseline risk assessment, the study and estimation of risk from
taking no activity. Involves estimates of probability and consequence.
Carcinogen
- A cancer-causing agent.
CERCLA
- Comprehensive Environmental Response, Compensation, and Liability
Act (also known as Superfund), the federal law that guides cleanup
of hazardous waste sites. Not all FUSRAP sites are Superfund sites.
CFR
- Code of Federal Regulations
Characterization
- Facility or site sampling, monitoring and analysis activities
to determine the extent and nature of a release. Characterization
provides the basis for acquiring the necessary technical information
to develop, screen, analyze, and select appropriate cleanup techniques.
Cleanup
- The general term for environmental restoration, the process designed
to ensure that risks to the environment and to human health and
safety from waste sites either are eliminated or reduced to prescribed,
safe levels.
Closure
plan - Documentation prepared to guide the deactivation, stabilization
and surveillance of a waste management unit or facility under the
Resource Conservation and Recovery Act.
Comment
period - Time provided for the public to review and comment formally
on a proposed action or decision.
Contamination
- The presence of foreign materials, chemicals or radioactive substances
in the environment (soil, sediment, water or air) in significant
concentrations.
Cubic
meters - A unit equal to the volume of a cube measuring one meter
in each dimension.
Cubic
yards - A unit equal to the volume of a cube measuring one yard
in each dimension.
Curie
- A unit of radioactivity that represents the amount of radioactivity
associated with one gram of radium. To say that a sample of radioactive
material exhibits one curie of radioactivity means that the element
is emitting radiation at the rate of 3.7 million times a second.
A smoke detector contains 10 microcuries of radiation, or 10 millionths
of a Curie. Named after Marie Curie, an early nuclear scientist.
Daughter
product - An element formed by the radioactive decay of another
element; often daughter products are radioactive themselves. Radon
is a daughter product of thorium.
Decay
- The process whereby radioactive particles undergo a change from
one form, or isotope, to another, releasing radioactive particles
and/or energy.
Decontamination
- The removal of unwanted material (typically radioactive material)
from facilities, soils, or equipment by washing, chemical action,
mechanical cleansing or other techniques.
Defense
wastes - Radioactive wastes resulting from weapons research and
development, the operation of naval reactors, the production of
weapons materials, the reprocessing of defense spent fuel, and the
decommissioning of nuclear-powered ships and submarines.
Dioxin
- One of the most hazardous of all chemicals, can cause both acute
and long-term effects ranging from chloracne, a skin disease, to
cancer, reproductive failures, and reduced resistance to infectious
disease.
Disposal
- Waste emplacement designed to ensure isolation of waste from the
biosphere, with no intention of retrieval for the foreseeable future.
DOE
- U.S. Department of Energy.
Dose
- Quantity of radiation or energy absorbed; measured in rads.
Dose
equivalent - A term used to express the amount of effective radiation
received by an individual. A dose equivalent considers the type
of radiation, the amount of body exposed, and the risk of exposure.
Measured in rems.
Dosimeter
- An instrument that measures exposure to radiation.
EA
- A written environmental analysis that is prepared under the National
Environmental Policy Act to determine whether a federal action would
significantly affect the environment and thus require preparation
of a more detailed environmental impact statement.
EE/CA
- Engineering evaluation and cost analysis, which is a CERCLA document,
prepared to address interim cleanup activities.
Effluent
- A waste discharged as a liquid.
EIS
- Environmental impact statement, required by the National Environmental
Policy Act. (See NEPA).
Electron
- An elementary particle with a unit negative charge and a mass
1/1837 that of the proton. Electrons surround the positively charged
nucleus and determine the chemical properties of the atom.
Element
- Any of the 109 substances that cannot be broken down further without
changing its chemical properties. Singly or in combination, the
elements constitute all matter.
Environmental
restoration - The process of environmental cleanup designed to ensure
that risks to the environment and to human health and safety from
waste sites either are eliminated or reduced to prescribed, safe
levels.
Erosion
control - Methods to control land surface features to prevent erosion
by surface water or precipitation runoff.
Exposure
- A measurement of the displacement of electrons from atoms caused
by X-rays or by gamma radiation. Acute exposure generally refers
to a high level of exposure of short duration; chronic exposure
is lower-level exposure of long duration.
Final
disposition - Methods for permanent disposal of waste or contaminated
soils after excavation/treatment.
Fission
- The splitting of a heavy nucleus into two or more radioactive
nuclei, accompanied by the emission of gamma rays, neutrons and
a significant amount of energy. Fission usually is initiated by
the heavy nucleus absorbing a neutron, but it also can occur spontaneously.
FR
- Federal Register
Friable
asbestos - Asbestos insulation that is loose and capable of becoming
airborne.
FS
- Feasibility study, the Superfund study following a remedial investigation,
which identifies, develops, evaluates and selects remedial action
alternatives.
FUSRAP
- Formerly Utilized Sites Remedial Action Program, which was created
in 1974 to study sites used during World War II through the 1950s
as part of the nation's atomic energy program. These early sites
were decontaminated under guidelines in effect during that period.
Using today's more-stringent environmental laws and better technology,
the U. S. Army Corps of Engineers will restore these environmentally
damaged sites.
Gamma
rays - Penetrating electromagnetic waves or rays emitted from nuclei
during radioactive decay, similar to X-rays. Dense materials such
as concrete and lead are used to provide shielding against gamma
radiation.
Geohydrologic
- Pertaining to groundwater and its movements through the geologic
environment.
Geohydrology
- The science dealing with underground water, often referred to
as hydrogeology.
Groundwater
- Water beneath the earth's surface that fills pores between materials
such as sand, soil or gravel. Groundwater is a major source of water
for agricultural and industrial purposes and is an important source
of drinking water for about half of all Americans.
Half-life
- The time required for a radioactive substance to lose 50 percent
of its radioactivity by decay. The half-life of the radioisotope
plutonium-239, for example, is about 24,000 years. Starting with
a pound of plutonium-239, in 24,000 years there will be one-half
pound of plutonium-239, in another 24,000 years there will be one-fourth
pound, and so on. (A pound of material remains, but it gradually
becomes a stable element.)
Hazardous
waste - A solid or liquid waste or combination of solid and liquid
wastes that, because of quantity, concentration or physical, chemical
or infectious characteristics, may cause or significantly contribute
to an increase in mortality or an increase in serious, irreversible,
or incapacitating reversible illness or pose a substantial hazard
to human health or the environment when improperly treated, stored,
transported, disposed or otherwise managed.
About
290 million tons of hazardous wastes are generated in the United
States each year. A small percentage (about 4 percent) is recycled.
The rest is treated, stored or disposed. Of the hazardous wastes
disposed, most are injected as a liquid into the ground in specially
designed injection wells. A large quantity is placed in surface
impoundments (pits, ponds and lagoons). A small portion is placed
directly on the land or buried.
Heavy
metals - Metals that have a dense molecular structure. Examples
include mercury, lead, silver, gold and uranium.
HEPA
Filter - High-efficiency particulate air filter.
High-level
radioactive wastes - Highly radioactive material, containing fission
products, traces of uranium and plutonium, and other transuranic
elements, that results from chemical reprocessing of spent fuel.
Originally produced in liquid form, high-level waste must be solidified
before disposal.
Holding
ponds - An impoundment made by excavation or earth fill for temporary
storage of liquid wastes.
Impoundment
liner - A continuos layer of natural or man-made materials, beneath
or on the sides of a surface impoundment, which restricts the downward
or lateral escape of by-product material, hazardous constituents,
or leachate.
IR
- Information Repository, where information relating to the Formerly
Utilized Sites Remedial Action Program may be found.
Ion
- Atomic particle, atom or chemical radical bearing an electric
charge, either negative or positive.
Ionization
- Removal of electrons from an atom, for example, by means of radiation,
so that the atom becomes charged.
Ionizing
radiation - Radiation that has enough energy to remove electrons
from substances it passes through, forming ions.
Isotopes
- Atoms of the same element that have equal numbers of protons,
but different numbers of neutrons. Isotopes of an element have the
same atomic number but different atomic mass. For example, uranium-238
and uranium-235.
Leachate
- The solution formed when soluble components have been removed
from a material.
Leaching
- To remove a soluble substance from a material by dissolving it
in a liquid, and then removing the liquid from what is left. Liquids
also can leach into soils and aquifers.
LLW
- Low-level waste, discarded radioactive material such as rags,
construction rubble, glass, etc. that is only slightly or moderately
contaminated. This waste usually is disposed of by land burial.
MCL
- Maximum concentration limit, the regulatory limit for various
constituents, usually organics and inorganics; there are different
levels for different media, such as air, soil, and water. The MCL
cannot be exceeded.
Millirem - A unit of radiation dosage equal to one-thousandth of
a rem. A member of the public can safely receive up to 500 millirems
per year, according to federal standards, but the U.S. EPA ordinarily
limits public exposure to 25 to 100 mrem/year.
Mixed
waste - Contains both radioactive and hazardous components.
Mobility
- The ability of radionuclides to move through food chains in the
environment.
Molybdenum
- A silver-white metallic element used as an alloy with iron in
making hard, high-speed cutting tools. It is not a heavy metal.
Monitoring
well - A hole drilled into the ground with a pipe inserted to allow
for the collection of groundwater samples.
Natural
radiation - Radiation that is always present in the environment
from such sources as cosmic rays and radioactive materials in rocks
and soils. Also known as background radiation.
NCP
- National Oil and Hazardous Substances Pollution Contingency Plan,
which implements CERCLA.
NEPA
- National Environmental Policy Act, requires a study of the impacts
of activities at federal facilities.
Neutron
- A particle that appears in the nucleus of all atoms except hydrogen.
Neutrons are one of three basic particles that make up the atom.
Neutrons have no electrical charge.
NOA
- Notice of availability, published when a document on some aspect
of cleanup is issued. Documents are available in the administrative
record and information repositories.
NPDES
- National Pollutant Discharge Elimination System.
NPL
- National Priorities List, the list of the nation's worst Superfund
sites.
NRC
- Nuclear Regulatory Commission
NTS
- Nevada Test Site, a repository for radioactive wastes.
Nuclear
radiation - Ionizing radiation originating in the nuclei of atoms;
alpha, beta, and gamma radiation.
Nucleus
- The central part of an atom that contains protons, neutrons and
other particles.
OSHA
- Occupational Health & Safety Act. Also the Occupational Health
and Safety Administration.
Pathways
- The means by which contaminants move. Possible pathways include
air, surface water, groundwater, plants and animals.
PCB
- Polychlorinated biphenyl, a synthetic, organic chemical once widely
used in electrical equipment, specialized hydraulic systems, heat
transfer systems, and other industrial products. Highly toxic and
a potent carcinogen. Any hazardous wastes that contain more than
50 parts per million of PCBs are subject to regulation under the
Toxic Substances Control Act.
Picocuries
- Measurement of radioactivity. A picocurie is one million millionth,
or a trillionth, of a curie, and represents about 2.2 radioactive
particle disintegrations per minute.
Plume
- A defined area of groundwater containing contamination that originates
from a particular source such as a waste unit.
Plutonium
- An artificially produced element that is fissile and radioactive.
It is created when an atom of uranium-238 captures a slow neutron
in its nucleus.
PP
- Proposed plan, a CERCLA document that summarizes what cleanup
remedy has been selected, and why. The public is permittd to comment
about the PP.
RA
- Risk assessment, the study and estimation of risk from a current
or proposed activity. Involves estimates of the probability and
consequence of an action.
Rad
- Radiation absorbed dose, a measurement of ionizing radiation absorbed
by any material. A rad measures the absorption of a specific amount
of work (100 ergs) in a gram of matter. The rad measures the amount
of energy deposited in a material. It is not a measure of biological
effect of that energy, but together with other factors is used to
calculate the biological effect in units of rem (see rem).
Radiation
- Fast particles and electromagnetic waves emitted from the nucleus
of an atom during radioactive disintegration.
Radioactive
- Giving off, or capable of giving off, radiant energy in the form
of particles (alpha or beta radiation) or rays (gamma radiation)
by the spontaneous disintegration of the nuclei of atoms. Radioisotopes
of elements lose particles and energy through the process of radioactive
decay. Elements may decay into different atoms or a different state
of the same atom.
Radioactive
waste - A solid, liquid or gaseous material of negligible economic
value that contains radionuclides in excess of threshold quantities
except for radioactive material form post-weapons-test activities.
Radioisotope
- An unstable isotope of an element that eventually will undergo
radioactive decay or disintegration. Radioisotopes with special
properties are produced routinely for use in medical treatment and
diagnosis, industrial tracers, and for general research.
Radionuclide
- A radioactive species of an atom.
Radium
- One of four primary radionuclides in FUSRAP wastes. They include
radium-226, radon-222, thorium-230, uranium-234, uranium-235 and
uranium-238.
Radon
- A radioactive gas produced by the decay of one of the daughters
of radium. Radon is hazardous in unventilated areas because it can
build up to high concentrations and, if inhaled for long periods
of time, may cause lung cancer.
RCRA
- Resource Conservation and Recovery Act, the federal environmental
law designed to account for and ensure proper management of hazardous
wastes, from creation to disposition.
Reclamation
- The act of processing of reclaiming. A restoration as to productivity,
usefulness.
Rem
- Roentgen equivalent man, a unit used in radiation protection to
measure the amount of damage to human tissue from a dose of ionizing
radiation. Incorporates the health risks from radiation. One rem
is roughly the average dose received in three years of exposure
to background radiation. A typical x-ray is equivalent to 0.03 rem
and a mammogram is about 0.3 rem.
Remedial
action - Long-term cleanup activities.
Remedial
design - A phase of remedial action that follows the remedial investigation/feasibility
study and includes development of engineering drawings and specifications
for a site cleanup.
Remediation
- Those activities performed to remove or treat hazardous waste
sites or to relieve their effects.
Removal
action - Interim cleanup activities that are identified as needed
to protect public health and the environment.
Restoration
- (See environmental restoration)
RI
- Remedial investigation, the CERCLA process of determining the
extent of hazardous substance contamination and, as appropriate,
conducting treatability investigations.
RI/FS
- Two distinct, but related studies, the remedial investigation
and feasibility study. Together, they characterize environmental
problems and outline remedial actions to solve those problems.
Risk
assessment - (See RA)
Risk
communication - The exchange of information about health or environmental
risks between risk assessors, risk managers, the general public,
news media, interest groups, etc.
Risk
management - The process of evaluating alternative regulatory and
non-regulatory responses to risk and selecting among them. The selection
process necessarily requires the consideration of legal, economic
and social factors.
ROD
- Record of decision, a written decision that identifies the selected
method for long-term cleanup of contamination at a site.
SARA
- Super-fund Amendments and Reauthorization Act
Scoping
- In CERCLA, scoping is the initial planning phase of the cleanup
process, when requirements are discussed and the projects defined.
In the NEPA process, scoping relates to public involvement to help
identify significant issues early so that efforts can be focused
on those areas requiring resolution and to present a balanced environmental
impact statement.
Sludge
- A semi-solid residue from any of a number of air or water treatment
processes. Sludge can be a hazardous waste.
Slurry
- A watery mixture of insoluble matter that results from some pollution
control techniques.
Solidification
- The conversion of either liquid or loose hazardous waste into
a solid.
Solubility
- A measure of how much of a given substance will dissolve in a
liquid. Usually measured in weight per unit volume.
Somatic
effects - Effects of radiation limited to the exposed individual,
as distinguished from genetic effects, which also affect subsequent,
unexposed generations.
Stable
isotope - An isotope of an element that is not radioactive.
Surface
impoundment - A natural topographic depression, man-made excavation,
or dike area, which is designed to hold an accumulation of liquid
wastes or wastes containing free liquids and which is not an injection
well.
Superfund
- The program operated under the legislative authority of CERCLA
and SARA that funds and carries out the EPA solid waste emergency
and long-term removal remedial activities. These activities include
establishing the National Priorities List, investigating sites for
inclusion on the list, determining their priority level on the list,
and conducting and/or supervising the ultimately determined cleanup
and other remedial actions.
Tailings
- Uranium mill tailings are the residual wastes of milled ore that
remains after the uranium has been removed. The tailings are generated
during the extraction of the uranium from the ore as it is fed to
the mill. Uranium mill tailings are primarily the sandy process
waste material from a conventional mill.
Thorium
- A naturally occurring radioactive element and one of four primary
radionuclides in FUSRAP wastes. They include radium-226, radon-222,
uranium-234, uranium-235 and uranium-238. It is used in lantern
mantles, in the production of ceramics and in alloys, among other
uses.
Threshold
dose - The minimum dose of radiation that will produce a detectable
effect.
Toxic
- Relating to a harmful effect by a poisonous substance on the human
body by physical contact, ingestion or inhalation.
Toxicology
- The science that deals with poisons and their effects on plant,
animal and human life.
Transuranic
wastes - Waste materials contaminated with isotopes above uranium
in the periodic table. Transuranic waste is long-lived, but only
moderately radioactive.
Treatment
- Any activity that alters the chemical or physical nature of a
waste to reduce its toxicity or prepare it for disposal.
Uranium
- The heaviest element found in nature. Approximately 997 out of
every 1,000 uranium atoms are uranium-238. The remaining 3 atoms
are the fissile uranium-235. The uranium-235 atom splits into lighter
elements when its nucleus is struck by a neutron. One of four primary
radionuclides in FUSRAP wastes, including radium-226, radon-222
and thorium-230.
U.S.
EPA - United States Environmental Protection Agency, sometimes referred
to as EPA.
Uranium
oxide - The generic name for a group of uranium compounds that includes
uranium dioxide (U02), uranium trioxide (U03), and uranas-uranium
oxide (U308), and uranium peroxide (U04.2H20).
USACE
- U.S. Army Corps of Engineers, the federal agency managing cleanup
of the Formerly Utilized Sites Remedial Action Program.
UST
- Any underground storage tank or associated piping containing hazardous
materials.
Vitrification
- A method of immobilizing waste that produces a glass-like solid
that permanently captures the radioactive materials.
VOCs
- Volatile organic compounds, chemicals that contain carbon and
commonly also contain hydrogen, oxygen and other elements. The prefix
"volatile" means that the compound evaporates rapidly.
Most industrial solvents are volatile. Found in some liquid and
air waste releases.
Waste
minimization - Employing new techniques to reduce the amount of
hazardous and radioactive wastes generated to as low a level as
possible.
WIPP
- Waste Isolation Pilot Project, a planned disposal facility in
New Mexico for transuranic and other radioactive waste.
X-rays
- Electromagnetic radiations used in medical diagnosis; a penetrating
electromagnetic radiation, usually generated by accelerating atoms
to high velocity and suddenly stopping them by collision with a
solid body.
Yellowcake
- Ammonium diuranate (NH4)2 U207, a uranium concentrate with a characteristic
yellow color. Yellowcake is the product of the uranium extraction
(milling) process: early production methods resulted in a bright
yellow compound, hence, the name yellowcake.
Concentration
Comparisons
Parts
per million:
-
One automobile in bumper-to-bumper traffic from Cleveland to San
Francisco
-
One drop of gasoline in a full-size car's tank full of gas
-
One facial tissue in a stack taller than the Empire State Building
One pancake in a stack four miles high
Parts
per billion:
-
One silver dollar in a roll of silver dollars stretching from Detroit
to Salt Lake City
-
One kernel of corn in enough corn to fill a 4.5 foot-silo, 16 feet
in diameter
-
One sheet in a roll of toilet paper stretching from New York to
London
Parts
per trillion:
-
One square foot of floor tile on a kitchen floor the size of Indiana.
One drop of detergent in enough dishwater to fill a train load of
railroad tank cars 10 miles long
-
One mile on a two-month journey at the speed of light
Parts
per quadrillion:
-
One postage stamp on a letter the size of California and Oregon
combined
-
The palm of one's hand resting on a table the size of the United
States. One human hair out of all the hair on all the heads of all
the people in the world
-
One mile in a journey of 170 light years
Sources:
Glossary of Environmental Restoration Terms and Acronym List (EPAIOPA-87-017,
August 1988)
Glossary
of Environmental Restoration (OE, Office of Environmental Restorations
and Waste Management, Oak Ridge Operations, October 1990 and October
1991)
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