The United States began using nuclear energy to commercially produce electricity in 1957. Since then, it has proven itself as one of our safest energy technologies. Its use is not without challenges, however; the biggest are issues of radioactive waste and the potential misuse of nuclear fuels for destructive purposes. Another challenge we face as a Nation is how to identify and properly train the next generation of nuclear scientists.

What is Nuclear Waste?

In the process of day-to-day living, people produce waste. Consider the amount of food scraps, used paper, and other trash that you and your family throw into the trash every day. Just think of how much waste one visit to a fast food restaurant creates - leftover food and drinks, bags, straws, cups and containers.

Industries also generate trash as a result of doing or making something. The leftovers of an industrial process are called waste.

Like all industries, nuclear power plants produce waste. But nuclear waste is not like normal garbage. The problem with nuclear power plants is not the amount of waste they make, which is quite small compared with the amount of waste produced by many other industries. The problem is that some nuclear power plant wastes are radioactive. This means that disposing of the waste requires special care to protect workers and the public. The way it is disposed of depends on how radioactive the waste is.

All nuclear waste is radioactive. It gives off invisible energy rays that can make people sick and even die if they're exposed to it. Nuclear waste will stay radioactive for hundreds of thousands of years.

Waste that is only slightly radioactive is called low-level waste. In the United States, about 55-60% of low-level waste comes from nuclear power plants and about 35% comes from industry and medicine. Low-level radioactive waste from a nuclear power plant includes such things as filters, cleaning rags, lab supplies, and discarded protective clothing. Hospitals, research labs, and agriculture also generate low-level waste.

Power plant waste that is very radioactive is called high-level waste. Most high-level waste from a nuclear power plant comes from spent (used) fuel. Spent fuel is fuel that has been removed from the reactor. Not only is it highly radioactive, but it produces a great deal of heat.

How Does the United States Dispose of Nuclear Waste?

Because it emits only small amounts of radiation, low-level waste is usually sealed in strong cartons or steel drums and placed in shallow burial sites that are regulated. States that produce low-level waste are responsible for disposing of it. As time passes, the waste becomes less radioactive as a result of radioactive decay.

Nuclear power plants store spent fuel near the reactor in a deep pool of water called the spent fuel pool. During storage, the spent fuel cools down and also begins to lose its radioactivity through radioactive decay. In 3 months, the spent fuel loses about 50% of its radiation. In one year, it loses about 80%, and in 10 years it loses 90%. Nevertheless, because some radioactivity remains for thousands of years, the waste must be carefully and permanently isolated from the environment.

Currently, spent nuclear fuel and high-level radioactive waste are stored in temporary facilities at some 125 sites in 39 states. These storage sites are located in a mixture of cities, suburbs, and rural areas. Most are located near large bodies of water.

In the United States today, more than 161 million people reside within 75 miles of temporarily stored nuclear waste.

> View Parade Magazine article: The Growing Problem of Nuclear Waste

> View Nuclear Waste Locations by State

How Will We Transport the Nuclear Waste?

When the time comes to ship nuclear waste to a permanent disposal location, the spent fuel will be carefully loaded into shipping containers, which are called spent fuel casks.

If you own a musical instrument, it probably has a case that you keep it in. The case prevents damage that could happen while you take your violin or saxophone to music class.

A spent fuel cask is similar to an instrument case in that both are specially made to protect their contents. In addition, a spent fuel cask must also protect people and the environment from the fuel it holds.

As a result, spent fuel casks are designed with heavy shielding that protects people from radiation, as well as with thick walls that prevent radioactive substances in the spent fuel assemblies from getting into the environment.

A typical spent nuclear fuel cask sitting on a railcar

A spent fuel cask is designed to withstand the worst sorts of disasters and accidents, and a series of tests is conducted on sample casks to ensure that the casks really work. These tests include:

• being dropped from 30 feet onto reinforced concrete;
• being dropped from 40 inches onto a thick steel bar;
• being burned in a 1,475 oF fire for 30 minutes, and'
• being put under 3 feet of water for 30 minutes.

These tests are carefully monitored and measured with high-speed cameras that help engineers and scientists study these containers under conditions that simulate an accident.

In one test, a spent fuel cask was even mounted on a tractor-trailer that was hit broadside by a train engine moving at 80 miles per hour. The impact demolished the train engine, but did not damage the cask. Afterward, the cask was put into a fire for two hours. Scientists carefully examined the cask for any damage and found that the cask's contents had remained intact.

> See videos of radioactive cask crash test simulations

In addition to all the requirements that casks must meet in order to be shipped by truck or train, the truck driver and train operator must be trained in the hazards of radioactive materials, transportation regulations, and emergency procedures. The route that the cask takes is also given careful consideration in order to avoid large cities and undesirable road conditions.

Since the early 1960s, the United States has safely conducted more than 3,000 shipments of used nuclear fuel without any harmful release of radioactive material.

How Can Nuclear Energy Be Misused?

Strict security precautions protect fuel for nuclear power plants in the United States and around the world. This is because uranium and plutonium, which serve as fuel for nuclear power plants, can also be used to make nuclear weapons. It takes highly enriched uranium or purified plutonium to make a bomb, however, and these materials are not as highly concentrated in commercial nuclear power plants. It is still important to make sure no one can steal nuclear fuel, and so very strict security measures are in place to protect the fuel at the power plant and during transportation.

A well-trained security force, physical barriers, electronic surveillance, and visitor screening are all part of the normal security at nuclear power plants. These measures also deter, prevent, and respond to any attempted theft or diversion of nuclear materials. During transportation, careful routing, armed security, and advanced communication equipment ensure that the used fuel safely reaches its destination.

Who Will Be Our Next Nuclear Scientists?

Interest in pursuing a career in nuclear energy was high in the 1970s. Many of our Nation's current nuclear physicists and nuclear engineers received their training then. Those scientists are looking forward to retiring in the coming decade. It is time to start preparing a new group of young scientists to take their places when they retire.

The problem is that students have not studied nuclear science in large numbers since the late 1970s. This is largely because there have been few jobs for them.

The most serious accident in U.S. commercial reactor history happened in March 1979 and brought the expansion of nuclear power plants to an abrupt halt. Instruments gave false readings in one of the reactors at the Three Mile Island power plant near Harrisburg, Pennsylvania, and the plant had to be shut down. No workers or citizens living in the vicinity of the plant received physical injuries, but a new level of extreme caution brought such strict regulations that no new nuclear plants have been permitted in more than 35 years. (To learn more about the accident at Three Mile Island, go to the “Things You Thought You Knew” section.)

The last power plant to be built in the United States is the Watts Bar Nuclear Power Plant on the Tennessee River near Spring City in east Tennessee. Construction on Watts Bar began in 1973, but operation did not begin until 1996. One of the plants two reactors is still not operational.

Without new jobs for nuclear scientists, nuclear science programs at universities have become less popular. As our Nation now looks to expand the safe use of nuclear energy, the challenge is to enhance training programs for nuclear scientists and to encourage young scientists to pursue nuclear studies and eventually careers in nuclear energy.