Nuclear Waste has come under sharp focus after the Fukushima Nuclear Disaster in which Spend Fuel Rods were one of the biggest causes of the radioactive emission which has led to the Japanese Accident being labelled as INES Level 7 which is equal to the Chernobyl Accident.One of the biggest disadvantages associated with Nuclear Energy is the problem of Nuclear Waste which is generated after the Nuclear Fuel (Uranium) is processed.The transuranic elements which are produced have half lives of hundreds of years making it a difficult proposition to transport,handle and dispose them.A Number of Nuclear Plants have not factored in the high costs of Nuclear Waste Disposal making it another big issue in the problem of Nuclear Waste

Types of Nuclear Waste

1. Uranium Tailings – Uranium tailings are the radioactive  materials that remain after uranium is extracted by milling ore mined from the earth. The most important radioactive component of uranium mill tailings is radium, which decays to produce radon. Other potentially hazardous substances in the tailings are selenium, molybdenum, uranium, and thorium.
2. Transuranic (TRU) Waste originates mostly from nuclear weapons production facilities .”Transuranic” refers to atoms of man-made elements that are heavier han uranium. The most prominent element in most TRU waste is plutonium. Most TRU waste does not emit high levels of penetrating radiation but poses a danger when small particles of it are inhaled . The radiation from the particles is damaging to lung tissue and internal organs. Another problem with TRU waste is that most of its radioactive elements are long-lived. For example, half of the original amount of plutonium-239 in the waste will remain harmful after 24,000 years.
3. Low-level Nuclear Waste Low-level Nuclear Waste is generated from hospitals, laboratories and industry, as well as the nuclear fuel cycle. It comprises paper, rags, tools, clothing which contain small amounts of mostly short-lived radioactivity. It is not dangerous to handle, but must be disposed of more carefully than normal garbage.It comprise of around 90% of the total volume of  waste generated and is not a major problem .Worldwide it comprises 90% of the volume but only 1% of the radioactivity of all radwaste.
4. Intermediate-level Waste contains higher amounts of radioactivity than low level waste and requires special shielding. It  comprises of  chemical sludges,nuclear reactor parts and contaminated materials from reactor and weapon decommissioning. It makes up 7% of the volume and only 4% of the radioactivity of all radwaste. Like Low Level Nuclear Waste it is not a big issue.
5. High-level Waste – High-level Waste is the biggest problem with the waste products from Nuclear Fission.High Level Waste is the Fuel and the Processed Fuel.Comprising  only 3% of the volume it has 95% of the radioactivity. It contains the highly-radioactive fission products and some heavy elements with long-lived radioactivity. It generates a considerable amount of heat and requires cooling, as well as special shielding during handling and transport.Spent Fuel Rods – The fuel for most nuclear reactors consists of pellets of ceramic uranium dioxide that are sealed in hundreds of metal rods. These rods are bundled together to form what is known as a “fuel assembly.” Depending upon the type and size of the reactor, a fuel assembly can weigh up to 1,500 pounds. As the nuclear reactor operates, uranium atoms fission (split apart) and release energy. When most of the usable uranium has fissioned, the “spent” fuel assembly is removed from the reactor.Until a disposal or long-term storage facility is operational, most spent fuel is stored in water pools at the reactor site where it was produced. The water removes leftover heat generated by the spent fuel and serves as a radiation shield to protect workers at the site.
6. Naturally occurring radioactive materials (NORM) generally contain radionuclides found in nature. There are two types of naturally occurring radioactive waste: discrete and diffuse. The first, discrete NORM, has a relatively high radioactivity concentration in a very small volume, such as a radium source used in medical procedures. The second type, diffuse NORM, has a much lower concentration of radioactivity, but a high volume of waste. – source EPA,WNA

Summary

Nuclear Waste is the biggest con of Nuclear Electricity after the potential risks of a plant meltdown.Note Nuclear Waste is an ongoing problem and it has not been resolved in the USA where a permanent facility at Yucca mountains has run into a massive controversy.The long life of High Level Nuclear Waste,its pernicious effects on human health and difficulty in handling and storing make it difficult problem.However Nuclear Electricity forms almost 15% of the global electricity production and the tons of Nuclear Waste have to be dealt with however problematic and dangerous it might be