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Superfund Fact Sheet

What is Superfund? The Superfund program is administered by U.S. Environmental Protection Agency (EPA) in cooperation with state and tribal governments. It allows EPA to clean up hazardous waste sites and to force responsible parties to perform cleanups or reimburse the government for cleanups led by EPA.

For a variety of reasons, hazardous commercial and industrial wastes were mismanaged and may pose unacceptable risks to human health and the environment. This waste was dumped on the ground or in waterways, left out in Superfund is the informal name for the the open, or otherwise improperly Comprehensive Environmental Response, managed. As a result, thousands of Compensation, and Liability Act (CERCLA). hazardous waste sites were created In 1980, Congress enacted CERCLA in throughout the United States. These response to growing concerns over the hazardous waste sites commonly include health and environmental risks posed by manufacturing facilities, processing hazardous waste sites. This law was plants, landfills, and mining sites. enacted in the wake of the discovery of chemically contaminated toxic waste Superfund was established in 1980 by an dumps such as Love Canal and Valley of act of Congress, giving EPA the funds and the Drums in the 1970s. authority to clean up polluted sites Some Superfund sites contain radioactive Goals of Superfund: contamination. This document was

Protect human health and the developed by EPA to answer questions environment by cleaning up polluted sites about radiation hazards and how EPA Involve communities in the assesses health risks from potential Superfund process exposure to radioactive contamination at Make responsible parties pay for Superfund sites. work performed at Superfund sites - 1 -

What are atoms? An element is a specific type of atom. All atoms of an element have the same To understand radiation and number of . For example, all radioactivity, it is important to atoms of oxygen have eight protons, understand atoms. while all atoms have 92 protons. Atoms are the very small particles that It is possible for atoms of the same make up our bodies and everything element to have different numbers of around us. Atoms consist of a central . These various forms are called nucleus made up of protons and . For example, while all atoms of neutrons. Protons are positively charged, oxygen have eight protons, isotopes of while neutrons have no charge. oxygen can have from four to 16 have a negative charge and (or go neutrons. around) the nucleus. Most atoms are What is Radiation? neutral, which means they have the same number of protons and electrons. Atoms Radiation is energy that travels in the that are not neutral are called ions. form of waves or high-speed particles. There are two types of radiation:

Atomic Structure Non- is low energy. It includes radio waves, ,

and visible . Non-ionizing radiation can generate heat, but it

does not have enough energy to remove electrons from atoms.

Ionizing radiation is high energy. It can remove tightly bound electrons

Proton from an atom. Ionizing radiation can be harmful to humans by damaging An atom consists of a central nucleus (made living tissue and increasing risk. of protons and neutrons) orbited by X-rays are a familiar form of ionizing electrons radiation.

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blocked by a piece of paper or by skin. Common Types of Radiation However, that give off alpha particles can be very harmful if they enter your body in other ways such as through the air, food, or water because your internal organs are not protected by skin. Beta particles are light weight, relatively fast moving particles. They can be blocked by a thin piece of metal or wood. Beta particles can penetrate (pass through) the outer layer of skin and cause radiation burns. Like alpha particles, beta particles can damage your health if In this fact sheet, the term “radiation” they enter your body. will mean ionizing radiation. Gamma rays are waves of pure energy What is Radioactivity? that often accompany beta and alpha particles. Gamma rays can pass Some isotopes of certain atoms are through the body and damage internal unstable. When these unstable atoms organs. A thick wall of metal or release ionizing radiation in the form of concrete is needed to absorb gamma waves or particles, it is called radiation. radioactivity. A radioactive atom is called a . When a radionuclide Radiation Penetrating Power emits (gives off) radiation, it is said to decay. There are three main types of radiation given off when a radionuclide Alpha decays: Beta

Alpha particles are heavy, relatively Gamma

slow moving, particles. They can be

Paper Wood Concrete - 3 -

Ionizing Radiation Found at Superfund Sites

Alpha Particles Beta Particles Gamma Rays

Two protons and two Made up of an electron Pure energy traveling neutrons bound together ejected from nucleus at the speed of light into a single particle Fast moving, low mass Often accompanies Description Heaviest and slowest particle the emission of alpha moving type of ionizing Negatively charged or beta particles radiation Has no rest mass and Positively charged no charge HIGH MODERATE LOW Interacts strongly with Interact less strongly Since they have no Ionizing surrounding material than alpha particles but mass and no charge, Very energetic more strongly than gamma rays interact Power gamma rays with with matter less than surrounding material alpha and beta particles LOW MODERATE HIGH Travels no more than a Able to travel several Able to travel few centimeters in air meters through air hundreds of meters Penetrating Can be stopped by a sheet Can be stopped by a through air Power of paper thin layer of metal or Can be stopped by a Unable to penetrate skin plastic thick concrete wall Can penetrate outer Able to pass through layers of skin the human body No health effects from Can cause skin burns Can cause harm from external exposure since from external exposure external exposure they are unable to Harmful if taken into Can pass into the Human penetrate skin the body (though not body and cause Health Very harmful if alpha- usually as harmful as internal radiation Effects emitting radionuclide is alpha particles) exposure taken into the body by ingestion,r breathing, or through an open wound

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What happens to radionuclides as they decay?

As radionuclides decay, they become new elements called daughter products, which are also known as decay products. These daughter products may or may not be radioactive themselves. If a daughter product is also radioactive, it in turn will decay to form a different daughter product. This process will continue until a measure activity. One curie is 37 billion stable, nonradioactive product is formed. decays per second. This unit is too large The of a radionuclide and all of its daughters is known as a to use at most Superfund sites to assess radiation risk, so EPA usually uses a unit . called a picocurie. One picocurie is equal What is half-life? to one trillionth of a curie, or about 2.2 radionuclide decays per minute. The rate a radionuclide decays is its half- life. Half-life is defined as the amount of EPA measures radioactive contamination time it takes for half of the amount of a by the number of picocuries measured in substance to emit radiation and change a specific amount of contaminated to a different substance. Radionuclide material. contamination, for half-lives can be very long or very short. example, is measured in picocuries per For example, uranium-238 has a half-life gram. of 4.5 billion years, while carbon-11 has a Why are radionuclides harmful to half-life of only a few minutes. human health? How is radioactivity measured? The human body is made up of atoms. Radioactivity is measured by the activity When radionuclides decay, they release of a material. The activity is the number alpha, beta, and gamma radiation. This of radionuclides that decay each second. radiation can break the bonds between EPA often uses a unit called a curie to the atoms, damaging living tissue and

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DNA. Usually, our bodies can repair this Ingestion – Eating contaminated food, type of damage, but sometimes there drinking contaminated water, or may be too much damage to repair. This accidentally ingesting small amounts damage to living tissue and DNA can lead of contaminated dust or soil. to cancer or other health effects. The risk External – Radiation emitting out from of cancer increases as exposure to a source such as radioactively radiation increases. contaminated soil or object, and then penetrating from outside of the body. How is measured?

Under most situations, radiation exposure is measured in dose. Dose is related to the amount of radiation absorbed by a person’s body. The unit for radiation dose that EPA uses is the millirem. Millirem relates the of radiation to the amount of biological damage from the radiation.

However, radiation exposure at Superfund sites is measured by cancer How can you be exposed to harmful risk. All radionuclides can cause cancer, and the cancer risk increases as exposure radiation? increases. Not all radiation has the same Radionuclides cause the most harm when biological effect, even when the absorbed they are inside of the body. There are dose is the same, however. Therefore, three ways to be exposed to EPA’s use of cancer risk accounts for the radionuclides: different types of radiation as well as its effects on different parts of the body. Inhalation – Breathing contaminated vapors, dust particles, or gas.

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How does EPA calculate risks to EPA may also calculate health risk from human health from radiation radiation exposure in dose per year, exposure at Superfund sites? measured in millirem per year. Some regulations at Superfund sites are based EPA assesses the health effects of on what EPA has calculated to be radiation by calculating excess cancer risk acceptable dose limits per year. posed by radioactive contamination. Excess cancer risk is the additional What is background radiation? probability that a person exposed to the Radiation is everywhere in our contamination will develop cancer over a environment. The average person in the lifetime. United States receives a radiation EPA considers excess cancer risk to be exposure of approximately 620 millirems any risk above the protective range. The per year from both natural and man- protective range is a probability that a made sources. For examples of radiation person exposed to radioactive and in our environment, see the chart chemical contaminants will have between “Relative Doses from Radiation Sources” a one in ten thousand and a one in a on page 9. These examples include million chance of developing cancer, cosmic radiation from space, medical known as the 10-4 to 10-6 cancer risk procedures, radiation found naturally in range. the soil and water, and indoor radon. However, at Superfund sites, EPA is It is important to note that, even in the comparing radioactive pollution at the protective range, most people will have site with background radiation of the less of a chance of developing cancer same radionuclides where the pollution than these numbers indicate. EPA uses occurs, such as in the soil and water. assumptions about exposure levels that are higher than most people’s actual exposure.

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Some Common Ways to be Exposed to Radionuclides at Contaminated Sites

Residential Soil Exposure

Agricultural Soil Exposure

Soil to Ground Water Exposure

Tap Water Exposure

Tap Water Ingestion - 8 -

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What if I want More Information?

If you would like to learn more about EPA’s Superfund program, you may want If you have questions about this to read the document “This is Superfund: document, you can contact Stuart Walker A Community Guide to EPA’s Superfund of EPA by e-mail at Program,” available online at: [email protected] or by telephone http://www.epa.gov/superfund/commun at (703) 603-8748. ity/today/pdfs/TIS%20FINAL%209.13.11. pdf

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