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Nuclear Waste Storage – A Complete Mess with Lack of Policy ,Temporary Nuclear Sites in USA,Japan and France waiting for a permanent Nuclear Facility

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Nuclear Waste is one of the most difficult waste products to transport and store because of its dangerous radioactive effects.Given the long life of some of the transuranic elements Nuclear Waste has to be stored in a safe manner for thousands of years which is a tough given that the chances of leakage become enormous in such a long time scale.Storing of Nuclear Waste has to be performed in a extremely complicated manner which is also enormously costly.Also there are problems of NIMBY with Nuclear Waste Storage as nearby residents don’t want such toxic waste stored anywhere close especially as it does not bring any economic or social benefits.Not there is no permanent storage site despite many decades of planning and billions of dollars being spent.While Japan and Europe reprocess the fuel in the hope that they will be used again that remains a dream with thousands of tons of HLW piling up.USA does not reprocess and also has more than 60,000 tons of nuclear waste waiting for a final home.Till then most of the spent nuclear fuel is being stored in spent fuel pools and dry casks making them vulnerable just like another Fukushima

Nuclear Storage – How it is Done

A typical nuclear power plant in a year generates 20 metric tons of used nuclear fuel.High Level Nuclear Waste and Spent Fuel Rods are the biggest problem in storing and disposing of Nuclear Waste.The Fuel Rod Assemblies  have to be stored for perhaps as long as 1 million years or more as their radioactive nature decreases. The copper and steel containers will be put underground and built to last as long as 100,000 years.

  1. Wet Storage or Spent Fuel Pools – The water-pool option involves storing spent fuel rods under at least 20 feet of water, which provides adequate shielding from the radiation for anyone near the pool. A typical spent fuel rod is about 12 feet long and 3/4 inch in diameter.The rods are moved into the water pools from the reactor along the bottom of water canals, so that the spent fuel is always shielded to protect workers. Most pools were originally designed to store several years worth of spent fuel. Due to delays in developing disposal facilities for the spent fuel, licensees have redesigned and rebuilt equipment in the pools over the years to allow a greater number of spent fuel rods to be stored.This is where the danger comes from as it was painfully revealed that the spent fuel pools in reactor 1-4 of Fukushima were the cause of most of the radiation emissions and hydrogen explosions.The vast majority of the assemblies are stored in water pools, and less than 5% are stored in dry casks
  2. Dry cask storage – Dry cask storage allows spent fuel that has already been cooled in the spent fuel pool for at least one year to be surrounded by inert gas inside a container called a cask. The casks are typically steel cylinders that are either welded or bolted closed. The steel cylinder provides a leak-tight containment of the spent fuel. Each cylinder is surrounded by additional steel, concrete, or other material to provide radiation shielding to workers and members of the public. Some of the cask designs can be used for both storage and transportation – source NEI
  3. Geologic disposal – The process of selecting appropriate underground facilities for high level waste and spent fuel has long been planned without a single big geolic site operational in the world yet.The basic concept is to locate a large, stable geologic formation and use mining technology to drill a shaft 500–1,000 meters below the surface where rooms or vaults can be excavated for disposal of high-level radioactive waste. Because some radioactive species have half-lives longer than one million years, even very low container leakage and radionuclide migration rates must be taken into account.

Future Nuclear Waste Storage Concepts

  1. Sea Based Storage Sea-based options for disposal of radioactive waste include burial beneath a stable plain, burial in a  zone that would slowly carry the waste downward into the Mantle.But given that this has international implications and any accident will lead to worldwide radiation.
  2. Space disposal – Space disposal is an attractive notion because it permanently removes nuclear waste from the environment. But the probability of an incident is high as space vehicles do not have the safety required for nuclear activities.The cost also would be prohibitive.

Nuclear Storage Sites in France- Reprocessing and Hope of Fast Breeders

France produces 1179 tonnes of nuclear waste per year, and reprocesses 852 tonnes. Still, fuel is only reprocessed once and then it, too, needs to be stored. France is expecting that engineers will eventually succeed in building a new type of nuclear reactor called a fast reactor that will use the waste it can’t reprocess as fuel.In France Used fuel is stored at reactor sites in spent fuel pools or dry casks.After which it send to La Hague . The recovered uranium and plutonium is then returned to the owners and the separated wastes are vitrified, sealed into stainless steel canisters, and either stored or returned.

Nuclear Storage Sites in Japan – Same Lack of Policy as France

apan has a policy of reprocessing all nuclear waste. The government and electric utilities state that this is the best policy for nuclear waste management since this process extracts the most highly radioactive materials and concentrates them into a relatively small volume as high level radioactive waste (HLW). The HLW is then vitrified (glassified) and put into stainless steel canisters. Japanese national law calls for permanent disposal of this high level waste in a deep geological final repository in a yet undesignated place in Japan.

The government estimates that approximately 31,000 canisters of HLW will be generated by nuclear power plant operation by the year 2010. Since a final repository site is yet to be determined for the high level waste, the vitrified HLW canisters now being generated by reprocessing in Europe are being shipped to Aomori Prefecture for temporary above ground storage for 30-50 years. – source Greenaction.

Nuclear Storage Sites in USA – Do Not Exist

The US has 65,192 tonnes of the waste but the nation has no place to permanently store the material, which stays dangerous for tens of thousands of years.Currently, there are no permanent disposal facilities in the United States for high-level nuclear waste; therefore commercial high-level waste (spent fuel) is in temporary storage, mainly at nuclear power plants.A permanent facility was planned in the Yucca Mountains in Nevada by the Congress in 1987.This  project that has long been the subject environmental and political opposition and with the Obama administration cutting funding this project appears to be in limbo after $9 billion was spent.

Currently High-level waste (spent fuel) is in temporary storage, mainly at nuclear power plants while low-level waste, three commercial land disposal facilities are available, but they accept waste only from certain states or accept only limited types of low-level wastes.

Low Level Waste Sites in USA

  1. Hanford, located in Hanford, WA. Hanford accepts waste from the Northwest and Rocky Mountain compacts.
  2. Barnwell, located in Barnwell, SC. Previously, Barnwell accepted waste from all U.S. generators. As of July 2008, Barnwell only accepts waste from the Atlantic Compact States (Connecticut, New Jersey, and South Carolina).
  3. Energy Solutions, located in Clive, UT. Energy Solutions accepts waste from all regions of the United States.

Abhishek Shah

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