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GLOSSARY

WWII - World War Two started in Europe when the Germans began invading other countries, and continued in the Pacific after Japan attacked the U.S.   The European war ended on May 7 1945, the war with Japan ended after the U.S. dropped a second nuclear bomb on Nagasaki, August 14th, 1945.

Domestic - an animal that has been kept by humans for companionship, comfort or food (dogs, cats, sheep, cows or chickens for example.

Habitat - The place where a plant or animal can usually be found.

Hot - A slang term for materials or object that are radioactive, usually above the state found in nature, as a result of exposure to radiation.  These may include tools used in cleaning buildings, protective clothing worn by workers, etc.

Atom - A particle of matter indivisible by chemical means.  It is the fundamental building block of elements.

Background radiation - The radiation of man's natural environment originating primarily from the naturally radioactive elements of the earth and from the cosmic rays. The term may also mean radiation extraneous to an experiment.

Cold War - this is a period in American History when we were in a sort of mind war with the Soviet Union and China.  No bombs were sent, but we spied on them, and they spied on us.  Our military and political leaders beieved it was important to have many weapons to prevent them from attacking us. This was a sort of a big, expensive version of cats puffing up their fur to look bigger before a fight (note how cats often back down in the end!)

Communism - A theory which advocates a state of society in which there should be no private ownership, all property being vested in the community and labour organized for the common benefit of all members; the professed principle being that each should work according to his capacity, and receive according to his wants.  Many Americans believed in parts of Communism, particularly the equality of people and social support for everyone.  In the 1950's Senator Joseph McCarthy began a campaign to track people who were considered Communist sympathizers within the U.S. The Soviet Union and China adhere(d) to Communist ideology.  The Soviet Union began to fall apart beginning in 1989 with the fall of the Berlin Wall.

Contamination - Radioactive material deposited or dispersed in materials or places where it is not wanted.

Curie - The basic unit used to describe the intensity of radioactivity in a sample of material. One curie equals thirty-seven billion disintegrations per second, or approximately the radioactivity of one gram of radium.

Dose - The amount - or dose - of radiation a nuclear worker is exposed to is closely monitored.  Employees wear personal dosimeters to keep records of how much radiation they pick up over the year.  If someone receives a high dose, they may be moved to a different job site so they aren't over exposed. (See REM below)

Groundwater - water stored in rock, sand, or gravel below ground surface (sometimes like a lake,) but usually just fills the space, pores, between the rock.  Groundwater may be millions of years old and very deep down, or may be just below the ground surface and easily used up.

Half-life - The time in which half the atoms of a particular radioactive nuclide disintegrate. The half-life is a characteristic property of each radioactive isotope.

Native - Native plants and animals (like native people) were in an area prior to white settlement.  As settlers came into an area they introduced food plants, decorative plants, and weeds.  Weeds are any plant that serve no useful purpose, they sometimes spread and take up habitat that used to belong to native species.  Sometimes non-native animals can push out all of the native ones.  In the Columbia River, a foreign clam has pushed out the native ones!

Radiation - Unstable atoms are said to be radioactive. In order to reach stability, these atoms give off, or emit, the excess energy or mass. These emissions are called radiation. The kinds of radiation are electromagnetic (like light) and particulate (i.e., mass given off with the energy of motion). Gamma radiation and X-rays are examples of electromagnetic radiation. Beta and alpha radiation are examples of particulate radiation. Ionizing radiation can also be produced by devices such as X-ray machines.

REM (Roentgen equivalent man), is the unit of measurement used measure the amount of damage to human tissue from a dose of ionizing radiation. An average American receives about 0.360 rems of radiation per year.

MREM - Millirem, common unit of radiation dose defined as one-thousandth of a rem. An average American receives about 360 mrem of radiation in a year. Other units are also used to measure radiation.

Tri-Party Agreement (TPA) - Signed in 1989 by the Washington State Dept. of Ecology, the US Dept. of Energy, and the US Environmental Protection Agency, the TPA sets guidelines and deadlines for cleanup of the Hanford Site.