environmental science ch. 9

Name the steps in the nuclear fuel cycle

1) Mining and milling 2) Enrichment 3) Fuel fabrication 4) Use of the fuel 5) Reprocessing or storage 6) Transportation

What is a nuclear chain reaction?

A nuclear chain reaction occurs when the neutrons released from a splitting nucleus strike the nuclei of other atoms causing those atoms to split. This results in more neutrons being released which causes other atoms to split, thus causing a chain reaction

Describe how a nuclear power plant generates electricity

A nuclear power plant generates electricity when the nuclei of radioactive atoms disintegrate and release energy which is used to heat water and produce steam. The steam turns a turbine that generates electricity

Describe the geologic processes that resulted in the formation of coal

Coal is formed when large quantities of plant material from swamps is trapped in sediment and subjected to heat and pressure

Name the three most important sources of energy

Coal, oil, and natural gas

Describe the differences between lignite, bituminous, and anthracite coal

Depending on the amount of time the organic plant material is trapped in the earth determines the type of coal. Lignite is the lowest quality because of its high moisture content. Bituminous or soft coal has the low moisture content but is abundant whereas anthracite has the highest carbon content (energy) however is rare

Describe three factors that can cause the amount of an oil reserve to increase

Economic conditions, technological advancement, and new deposits discovered changes the amount of oil reserves

What environmental concern has caused people to be more accepting of nuclear power?

Global warming caused by release of greenhouse gases by burning fossil fuels has caused people to look to nuclear power for a "greener" solution

What environmental advantage does natural gas have over oil and coal?

Natural gas releases less carbon dioxide than oil as well as less air pollutants

Describe the processes that resulted in the formation of oil and natural gas

Oil and natural gas are formed from marine organisms that accumulate in the ocean floor and are buried in sediment. These organisms break down the released oil into the sediment which depending on the type of sediment traps the oil

What is the most common environmental problem associated with the extraction and transportation of oil?

Oil spills are the most common problem associated with oil extraction

How does radiation cause damage to organisms?

Radiation damages the DNA and other molecules of cells

What are the products of the nuclear disintegration of a radioactive isotope?

Radiation is the product of the disintegration of a radioactive isotope

What are secondary and tertiary oil recovery methods? Why is their use related to the price of oil?

Secondary recovery methods include pumping water or gas into the well to drive the oil out of the pores in the rock.These techniques typically result in up to 40 percent of the oil being extracted. Tertiary recovery methods include pumping steam into the well to lower the viscosity of the oil and allow it to flow more readily. These methods are expensive and will be used if extraction is profitable. This is why the price of oil is high

What happens during Stage 1 of the decommissioning of a nuclear power plant?

Stage 1 involves removing fuel rods and water used in the reactor and properly storing or disposing of them. This removes 99 percent of the radioactivity. The radioactive material remaining consists of contaminants and activated materials. Activated materials are atoms that have been converted to radioactive isotopes as a result of exposure to radiation during the time the plant was in operation. These materials must be dealt with before the plant can be fully decommissioned

What regions of the world have the largest reserves of coal? Of oil? Of natural gas?

The US and China have the largest reserves of coal. The Middle East and Euroasia has the largest oil reserves and a large portion of the natural gas reserves

What are the major environmental problems associated with the use of nuclear power?

The major environmental problems associated with nuclear power is the disposal of high-level radioactive waste, exposure to radioactivity during mining, processing, and transportation, and threat of accidents

What options are available during Stage 2 of the decommissioning of a nuclear power plant?

There are three options to this second stage of the decommissioning process. 1. Decontaminate and dismantle the plant as soon as it is shut down. 2. Secure the plant for many years to allow radioactive materials that have a short half-life to disintegrate and then dismantle the plant. (However, this process should be completed within 60 years.) 3. Entomb the contaminated portions of the plant by covering the reactor with reinforced concrete and placing a barrier around the plant.

List the three primary methods of protecting people from damaging radiation

Time, distance, and shielding are the basic principles of radiation protection

Distinguish between reserves and resources

resource is a naturally occurring substance of use to humans that can potentially be extracted. Reserves are known deposits from which materials can be extracted profitably with existing technology under prevailing economic conditions.

List three environmental impacts of the use of coal

• Landscape disturbance- Surface mining disrupts the landscape, as the topsoil and overburden are moved to access the coal. • Acid mine drainage- Since coal is a fossil fuel formed from plant remains, it contains sulfur, which was present in the proteins of the original plants. • Air pollution Dust- is generated by mining and transportation of coal. The large amounts of coal dust released into the atmosphere at the loading and unloading sites can cause local air pollution problems

What happened at Chernobyl, Three Mile Island, and Fukushima? Why did it happen?

• The accident at Chernobyl was the result of a nuclear reactor meltdown in association with a test and several safety violations and mistakes. The immediate consequences were 31 deaths, 500 persons hospitalized, and 116,000 people evacuated. Delayed effects include an increase in thyroid cancer in exposed children and fetuses. • Three Mile Island- On March 28, 1979, the main pump that supplied cooling water to the reactor broke down. the accident was caused by a combination of equipment failures, lack of appropriate information to the operator, and decisions by the operator. • Fukushima- On March 11, 2011, a magnitude 9 earthquake 130 km off the northeast coast of Japan triggered the automatic shutdown of several nuclear reactors in the vicinity of the earthquake. The loss of the ability to cool the reactors and their adjacent spent fuel storage sites resulted in explosions and fires that were caused by the release of hydrogen from the overheated reactors and one of the spent fuel storage sites