Nuclear Energy - Nuclear Safety Problems

Problems have plagued the nuclear industry almost from the beginning. Some plant-site selections have been considered questionable, especially those near earthquake fault lines. Several major accidents have occurred worldwide since the late 1970s.

In the United States

THREE MILE ISLAND. On March 28, 1979, the Three Mile Island nuclear facility near Harrisburg, Pennsylvania, was the site of the worst nuclear accident in American history. Information released several years after the accident revealed that the plant came much closer to meltdown than either the NRC or the industry had previously indicated. Temperatures inside the reactor were first said to have been 3,500 degrees Fahrenheit but are now known to have reached at least 4,800 degrees. The temperature needed to melt uranium dioxide fuel is 5,080 degrees Fahrenheit. When meltdown occurs, an uncontrolled explosion may result, unlike the controlled nuclear reaction of normal operation.

The emergency core cooling system at Three Mile Island was designed to dump water on the hot core and spray water into the reactor building to stop the production of steam. During the accident, however, the valves leading to the emergency water pumps closed. Another valve was stuck in the open position, drawing water away from the core, which then became partially uncovered and began to melt. The emergency core cooling system then began drawing water out of the basement supply and reusing it, contaminating the reactor pump, although limiting the radiation contamination to the interior of the building.

Although safety systems at the Three Mile Island facility performed well and the radiation leak was relatively small, the Three Mile incident was sensationalized in the media. Antinuclear proponents urged residents to evacuate, adding to stress levels and panic. In the end this nuclear accident resulted in no deaths or injuries to plant workers or members of the nearby community. On average, area residents were exposed to less radiation than that of a chest X-ray. Nevertheless, the Three Mile Island incident raised concerns about nuclear safety, which resulted in safety enhancements in the nuclear power industry and at the NRC. Antinuclear sentiment was fueled as well, heightening Americans' criticism of nuclear power as an energy source.

The nuclear reactor in Unit 2 at Three Mile Island has been in monitored storage since it underwent cleanup. Operation of the reactor in Unit 1 resumed in 1985.

PEACH BOTTOM. In 1987 the NRC shut down the Peach Bottom nuclear plant in Delta, Pennsylvania, because control-room operators were found sleeping on duty. This was the first plant shut-down solely because of operator violations and misconduct.

In the Former Soviet Union

CHERNOBYL. On April 26, 1986, the most serious nuclear accident ever occurred at Chernobyl, a four-reactor nuclear plant complex located in the former Soviet Union (now Ukraine) near Kiev. At least thirty-one people died and hundreds were injured when one of the four reactors exploded during a badly-run test of the reactor. Everyone in the vicinity was exposed to radiation, and radioactive particles were released into the atmosphere. About 500 people were hospitalized, and medical experts estimate that 6,000 to 24,000 cancer-related deaths have occurred over the intervening years as a result of the released radiation.

The cleanup was one of the biggest projects of its kind ever undertaken. Helicopters dropped 5,000 tons of limestone, sand, clay, lead, and boron on the smoldering reactor to stop the radiation leakage and reduce the heat. Workers built a giant steel and cement sarcophagus (stone coffin) to enshrine the remains of the reactor and contain the radioactive waste. Approximately 135,000 people were evacuated from a 300-square-mile area around the power station. Topsoil had to be removed in a nineteen-mile area and buried as nuclear waste. Buildings were washed down and the newly contaminated water and soil were carted away and buried. Agricultural products from areas nearby were declared unmarketable throughout Europe. Many of the 600,000 people involved in the immediate cleanup have suffered long-term effects of radiation exposure.

Some people at Chernobyl received 400 rems of radiation immediately following the explosion. (A rem is a standard measure of the whole-body dose of radiation. Under normal conditions, a person receives about one-tenth of a rem annually.) With a dose of twenty-five rems, a person's blood begins to change. The DNA is damaged, preventing the bone marrow from producing red and white blood cells. Sickness starts at 100 rems and severe sickness at 200 rems. Death of half the population occurs at 400 rems, and death within a week can be expected for anyone exposed to 600 rems. One estimate is that 17.5 million people, including 2.5 million children under seven years old, have had some significant exposure to radiation from Chernobyl.

In 1995 the United Nations reported that the prevalence of illnesses of all kinds was 30% above normal in the Ukraine; incidences of depression, alcoholism, and divorce were on the rise. Although the Chernobyl reactor is in the Ukraine, the neighboring nation of Belarus (with a population of 10 million people) suffered more human and ecological damage from fallout because of the prevailing winds. Thyroid cancers were 285 times pre-Chernobyl levels in Belarus in 1995, especially among children. Belarus's cabinet minister claimed at that time that a quarter of his country's national income was being spent on alleviating the effects of the disaster. As many as 375,000 people in Belarus, Ukraine, and Russia were displaced because of the accident. Contaminated forests spread radioactivity through fires, and seepage from the reactor has polluted waterways as far away as the Black Sea, some 350 miles away.

In April 1996 a fire in the woods near the Chernobyl reactor once more alarmed observers, who feared further danger to the entombed reactor and the release of radioactivity from soils and vegetation in the area. In addition, the sarcophagus built to contain the damaged reactor is reported to be crumbling. However, the Ukraine, which suffers from 40% unemployment and other enormous economic woes, claims it needs the power from the remaining reactor and that completely shutting down Chernobyl would cost too much.

Some high-technology companies have developed robots to clean up hazardous sites such as Chernobyl. Such efforts would, however, produce yet another problem: what to do with the radioactive waste once the Chernobyl sarcophagus is entered and cleaned up.