The government of India is promoting nuclear energy as a solution to the country’s future energy needs and is embarking on a massive nuclear energy expansion




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Part III: Radiation Emission in Nuclear Fuel Cycle


Man-made radiation is released during all stages of the nuclear fuel cycle.

1. Uranium Mining

Uranium miners are exposed to radiation emitted by a number of lethal uranium daughters, the most dangerous being: (i) the radioactive gas radon-222—deposits in the lungs, to cause lung cancer; (ii) radium-226 (half-life 1,600 years)—deposits in the bones to cause bone cancer and leukaemia.

As a result, uranium miners suffer from a very high incidence of cancer. One-fifth to one-half of the uranium miners in North America have died and are continuing to die of lung cancer. Records reveal that uranium miners in other countries, including Germany, Namibia and Russia, suffer a similar fate.17
Waste Rock

The waste produced during mining, called waste rock or mine tailings, is in huge quantities—lakhs of tons. It is left lying in the open in huge heaps adjacent to the mine. This waste rock contains uranium ore of too low grade for processing in the mill. It also contains decay products of uranium. Being radioactive and toxic, they contaminate the environment, and will continue to do so even after the shutdown of the mines, to cause disease among people living near the mines for thousands of years: radon gas can escape into the air; radium-226 containing ore dust can be blown by the wind; and uranium and its decay products can seep into surface water bodies and groundwater.

The reason why the world is not bothered about these impacts is because 70% of the world’s uranium lies on indigenous lands.18 Thus, most uranium mines in the USA are situated near indigenous tribal lands of the Navajo nation, in the American Southwest. The radioactive wastes have contaminated the air, soil, groundwater and even the Colorado River. They are taking a terrible toll: thousands of Navajos are suffering and dying from uranium-induced cancers. No one knows how many exactly, because the authorities do not keep a track. Epidemiological studies reveal that Navajo children living near the mines and mills suffer 5 times the rate of bone cancer and 15 times the rate of testicular and ovarian cancers as other Americans.19

2. Uranium Milling and Mill Tailings20


Uranium mills are normally located near the mines to save transportation costs. The wastes generated from the milling process are in the form of sludge and are called uranium mill tailings. They are pumped to settling ponds, where they are abandoned.

Since uranium represents only a minor fraction of the ore (for example 0.1%), the amount of sludge or mill tailings is nearly identical to that of the ore mined. Since it is not possible to extract all of the uranium present in the ore, therefore, the sludge contains 5% to 10% of the uranium initially present in the ore; it also contains all the remaining radioactive constituents of the ore.

The sludge thus contains 85% of the initial radioactivity of the ore. One of its deadly radioactive constituents is thorium-230, a uranium decay product with a half-life of 80,000 years. This means that it emits radioactivity for lakhs of years! Th-230 is especially toxic to the liver and the spleen, and also causes leukaemia and other blood diseases. It decays to produce radon gas, a very powerful cancer-causing agent. Even though radon-222 has a comparatively short half-life of 3.8 days, its quantity will not diminish for a long time, because it is constantly being replenished by the decay of the very long-lived thorium-230.

Hence, the tailing ponds will continue to radioactively contaminate the environment and affect the health of the people living nearby for hundreds of thousands of years:

  • Radon gas can travel many miles with a light breeze in just a few days.

  • Seepage from the tailing ponds is inevitably going to contaminate the ground and surface water. This is happening at tailing ponds all over the world.

  • Heavy rains can cause a spillover of the sludge into nearby areas. Has occurred at several tailing ponds.

  • Or, the tailings dam may fail! The failure can be huge. For instance, on July 16, 1979, the Church Rock tailings dam in New Mexico collapsed, spilling 340 million litres of liquid radioactive waste and eleven hundred tons of solid mill waste into the Rio Puerco River. It is the largest release of radioactive waste ever in the US.

The tailings therefore need to be safeguarded for tens of thousands of years. In practice, the settling ponds are simply abandoned. Only when there is a major seepage from the pond, or the dam breaks, do governments move to take some damage control measures.

3. Routine Radiation Releases from Nuclear Plants


The process of splitting uranium in nuclear reactors creates more than 200 new, radioactive elements that didn’t exist till uranium was fissioned by man. The resulting uranium fuel is a billion times more radioactive than its original radioactive inventory. A regular 1,000 megawatt nuclear power plant contains an amount of long-lived radiation equivalent to that released by the explosion of 1,000 Hiroshima-sized bombs.21

The diabolical elements created in the fission reaction leak out through cracks in the zirconium fuel rods. They now find their way into the environment through a number of ways. One way is that they mix with the primary coolant, that is, the water that cools the reactor core, making it radioactive. The primary coolant is piped through a steam generator to heat the water in the secondary cooling system. The primary coolant is not supposed to mix with the secondary coolant, but it routinely does (through cracks in the piping). Nuclear utilities in the US admit that about 45 litres of intensely radioactive primary coolant leaks into the secondary coolant every day.22 The secondary coolant is converted to steam to drive the turbines. Being at very high pressure, some radioactive steam routinely escapes into the environment from the reactor.

Apart from mixing with the primary coolant, radioactive gases leaking from fuel rods are also routinely released into the atmosphere at every nuclear reactor. This is known as “venting”. The nuclear industry claims that filters are used to remove the most radioactive isotopes, but in reality not all dangerous isotopes are removed and some escape into the environment.23

Finally, as we discuss in the next chapter, nuclear plants are inherently prone to accidents. Even if a major accident does not take place, accidental releases of large quantities of radioactive water or gases take place very frequently.
Radioactive Elements in Emissions

The radioactive steam and gases released into the atmosphere from nuclear reactors contain small amounts of the deadly radioactive elements created during the fission reaction. Some of these are:

  • Cesium-137 (half-life 30 years): it mimics potassium and tends to concentrate in the muscle cells in the body, causing cancer.

  • Strontium-90 (half-life 28 years): the body treats it like calcium and so it concentrates in breast milk and bones, to cause breast cancer and bone cancer years later.

  • Iodine-131 (half-life 8 days): it is very carcinogenic; on entering the body, it concentrates in the thyroid, to cause the rare thyroid cancer.

An important toxic isotope that is routinely emitted in large quantities from nuclear power plants is tritium (H-3), a radioactive isotope of hydrogen. It has a half-life of 12.4 years and as such is radioactive for 248 years. H-3 combines readily with oxygen to form tritiated water (H3O). Since this is chemically the same as water, it is not trapped by filters, and so continuously finds its way into the atmosphere. In September 2010, the US NRC acknowledged that more than half of America’s atomic reactors are leaking radioactive tritium. The “allowable” standard for radioactive tritium in drinking water in the US is 740 becquerels per litre of water; at 9 sites covering 18 reactors, the tritium levels were above 37,000 Bq/litre!24 In Canada, tritium levels in groundwater at the site of its Pickering “A” nuclear reactors were found to be as high as 700,000 Bq/litre.25

Tritium is readily absorbed through the skin, lungs and the GI tract into the human body. It causes tumours and cancer in the lungs and GI tract. In animal experiments, even at low doses, it has been shown to shrink the testicles and ovaries, and cause birth defects, ovarian tumours, mental retardation, brain tumours, decreased brain weight, and stunted, deformed foetuses.
Leakages due to Radioactive Corrosion

Apart from being created during the fission reaction, radioactive products are also created in another way in the nuclear reactor: due to bombardment of the metal piping and the reactor containment by neutrons. This is known as radioactive corrosion, or CRUD. The radioactive elements thus created include cobalt-60, iron-55, nickel-63, etc. During shutdowns of nuclear reactors for maintenance or refuelling, pipes, heat exchangers, etc. are routinely flushed to remove the highly radioactive CRUD build-up. This is now sent to radioactive waste dumps, from where the carcinogenic radioactive isotopes leak out to contaminate water and food supplies.26
To Sum-up

From the above analysis, it is obvious that though the nuclear industry claims it is “emission” free, it is in fact collectively releasing millions of curies into the environment annually.

Impact on Human Life


The routine emission and accidental leakages of radiation from nuclear plants obviously means that there must be increased incidence of cancer and other diseases in the people living around them. Very few studies have been done on this issue; these have come up with alarming findings. A study by researchers at the prestigious Medical University of South Carolina, USA found evidence of elevated leukaemia rates among children and young people living near nuclear facilities at 136 nuclear sites in the United Kingdom, Canada, France, United States, Germany, Japan and Spain. Elevated leukaemia rates among children were also found in a recent study that examined areas around all 16 major nuclear power plants in Germany.27 A Canadian federal government study found high rates of Down’s Syndrome in communities living near the Pickering nuclear generating station.28

Impact on Marine Life


Many nuclear plants around the world rely on what are known as “once through cooling systems” to cool the steam after it has passed through the turbine. This steam is now made to flow over pipes containing cold water from the river/sea, the so-called third circuit (see Pressurised Water Reactor, Chapter 1, Part III). Here it gets condensed into water, after which it is pumped back to the steam generator, while the water in the third loop is dumped back into the river or sea from where it was taken.

Nuclear plant authorities claim that this intake and discharge of water from the sea does very little harm to marine life. This claim has been questioned in a report Licensed to Kill: How the nuclear power industry destroys endangered marine wildlife and ocean habitat to save money, released by the well-respected Nuclear Information and Resource Service (NIRS), USA, on February 22, 2001; its findings have since been confirmed by other environmental and marine authorities in the USA.29 The report brings out in devastating detail the impact of these “once through cooling systems” on marine life. These cooling systems suck in and discharge as much as four million litres of water per minute. This huge amount of water is sucked in at such a high velocity that along with the water, marine life is also sucked in. The bigger marine animals impinge on “prevention devices” such as screens and barrier nets, and either drown or suffocate. While billions of smaller organisms, including small fish, fish larvae and spawn, pass through these screens and are drawn into the reactor cooling system where they get scalded and killed. US marine authorities are now claiming that it is these cooling systems that are responsible for the extensive depletion in fish stocks along the Atlantic coast.

With millions of litres of hot water being discharged into the waterway every minute, the total heat dumped into the waterway is tremendous. For instance, the nuclear power plants at Salem, New Jersey, USA, dump about 30 billion BTUs of heat hourly into Delaware Bay. That is the equivalent of exploding a nuclear bomb of the size that destroyed Hiroshima in the waters of Delaware Bay every two hours, all day, every day!

Such a huge hot water discharge leads to a temperature rise of the sea by 10-13 degrees Celsius and dramatically alters the immediate marine environment. It in fact creates a virtual marine desert.

4. Radioactive Waste: Leaking Everywhere


Probably the most monstrous problem created by nuclear power is that of spent fuel. Each 1,000 MW nuclear power plant generates 30 tons of radioactive waste annually. This is intensely radioactive, and is going to remain so for more than two lakh years! To get an idea of the deathly nature of this waste, let us discuss just one of its constituents, Plutonium-239.

Plutonium: Pu-239 is so toxic and carcinogenic that less than one-millionth of a gram if inhaled will cause lung cancer. It deposits in the liver to cause liver cancer, deposits in the bone marrow to cause bone cancer and leukaemia, and deposits in the testicles to cause mutations in reproductive genes and increase the incidence of genetic disease in future generations. The half-life of plutonium-239 is 24,400 years; so once created, it is going to cause cancers and genetic mutations for 5 lakh years!

Even though nuclear power plants have been in operation for more than fifty years now, mankind has not yet found a way of safely disposing of this lethal waste. Forget the long term, attempts to build even medium term storage sites for these wastes have failed. To give a few examples:

  • As of 2008, more than 64,000 tons of deathly nuclear reactor waste had accumulated in the United States. It is currently stored at 121 locations in 39 states across the country. For the last 30 years, the US government had been trying to build a waste repository at Yucca Mountain in Nevada. After spending $13.5 billion on it, finally in 2010, President Obama cancelled the project and set up a panel of experts to find new ways to manage this waste.30

  • The German government has invested several hundred million euros in research at the Asse nuclear storage facility in Lower Saxony in an attempt to solve the permanent waste storage problem of the nuclear energy industry. Recently, it was discovered that the site is in danger of collapsing, and authorities are now making an unprecedented attempt to retrieve and relocate hundreds of tons of waste from the site.31

That these attempts have failed should be no cause for surprise. Leave aside the problem of building a permanent storage system for this waste, considering its intensely radioactive and chemically corrosive nature, how do you guarantee that any storage system will not leak in say, a 100 years?

Since there is no way of removing the radioactive nature of these wastes, presently, in most countries, radioactive waste from nuclear power plants is stored in temporary storage sites near the reactors, either in huge cooling pools or in dry storage casks. Everywhere, this exceedingly toxic waste is leaking, leaching, seeping through the soil into aquifers, rivers, lakes and seas, to ultimately enter the bodies of plants, fish, animals and humans.32 Its consequences are going to be with us for the rest of time.

5. Reprocessing: Worsening the Waste Problem


Currently, six countries with nuclear reactors, China, France, India, Japan, Russia and the United Kingdom, reprocess at least some of their spent fuel.

Supporters of reprocessing argue that it reduces the nuclear waste problem by segregating out the high-level radioactive waste—only this reduced volume now needs to be stored for thousands of years. Decades of experience from reprocessing plants the world over provides overwhelming evidence that not only is this not true, reprocessing actually worsens the problems created by nuclear energy:

  1. As all the equipment used in reprocessing becomes radioactive, reprocessing increases the total volume of waste to be dealt with—by a factor of seven, according to the US Department of Energy (DOE)!33

  2. Reprocessing as a waste management technique is far more expensive than direct disposal, primarily because of the enormous capital cost of the reprocessing facility.34

  3. Reprocessing plants discharge huge quantities of radioactive waste into the sea and air. For instance, the Sellafield reprocessing plant in the UK is one of the biggest sources of radioactive pollution in Europe. It discharges some 8 million litres of nuclear waste into the Irish Sea each day, making it one of the most radioactively contaminated seas in the world. Contamination levels in the vicinity of the Sellafield complex exceed the contamination levels inside the Chernobyl exclusion zone. The effects of this terrible contamination are visible in the local population. There has been a ten-fold increase of childhood leukaemia and non-Hodgkin’s lymphoma around Sellafield, as compared to the British average.35
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