Your Questions About Recycling

The Expert answers:

BENEFITS OF RECYCLING

Recycling saves resources
Using recycled materials in manufacturing reduces the need to destroy habitat and ecosystems in the extraction of raw materials. Fewer clear cuts, strip mines and oil drilling operations mean more of earth’s ecosystems remains intact.

Recycling saves energy, reduces pollution
Using recycled content instead of bauxite ore to make aluminum cans reduces energy use by 95%, water pollution by 97% and air pollution by 95%.

Recycled content in writing paper reduces energy use by 33%, air pollution by 73% and water pollution by35%.

Glass manufacturing with recycled content reduces energy use by 5%, air pollution by 22 % and manufacturing waste by 75%.

The Expert answers:

The current recycling business model is Single Stream Recycling, where by recyclables are collected from homeowners for a monthly fee and sorted either by hand or by machines, then sold if there is an available market, if not, the recyclables are stored and finally sent to a landfill.

Paper recyclables, if not contaminated by oils such as food contamination can be mixed with fresh wood pulp to make degraded products that people often don’t buy due to the lower quality, they can’t be used for food packaging due to the risk that some recyclable may have been contaminated by the end user and the fact that sample testing would not be able to prevent the contamination. Oil contamination usually can not be detected until an entire batch fails to mesh in random spots causing a large amount of recyclables and new material to be thrown away. A single pizza box that slips into the recycling system can ruin a ton of wood pulp. Also, the market for low quality newsprint was newspapers and the market for newspapers has diminished greatly so for the most part the recycled paper have bee increasingly sent to the landfill.

Type 1 and type 2 plastics are also typically from food containers and as it’s impossible to prevent a consumer from using a container for other purposes, they can not be recycled into food containers therefore the market is to make insulation from them for clothes, sleeping bags, home insulation and as a filler material in synthetic wood and parking curbs. As this is not an end to end recycling, the market depends on continued economic growth to create a demand. Often the market will lapse and the recyclables are sent to the landfill.

Metals can be fully recycled. However the concentrations are not as predictable as raw ore, can not be tested by sampling ( a sample of ore is indicative of what the ore is but a sample of recycled cans is only representative of the sample ) and although the contamination problem is muted by the smelting process, it still prevents end to end recycling. Currently there is still a high demand for recycled metals so they are unlikely to be sent to the land fill.

In general recycling collects an extra fee from the consumer and sorts the waste before delivery to the landfill. Until people actually buy products made from recycled materials, they are deluding themselves into believing they are environmentally friendly. What we currently have is not recycling but green washing.

The Expert answers:

1. Recycling prevents resource destruction.
To understand the value of recycling, we must look at the entire lifecycle of a product from
the extraction and processing of raw materials, to the manufacture and consumption of the
product, and then to its final disposal. Recycling creates a closed-loop system where discarded
products are returned back to manufacturers for use in new products. This prevents the pollution
and destruction that occurs when virgin materials—like trees and precious metals—are extracted
from the earth.
Sustainable resource management, through recycling and similar activities like water and energy
conservation and green building, is no longer a personal decision but a necessary practice in a
world with a growing population and a finite resource base. We must greatly expand recycling
infrastructure around the world and incorporate sustainability into everyday personal and
business practices for the future of our economy, our health and our environment.
Just look at what one community can do: using the National Recycling Coalition’s
environmental savings calculator, the collection of 135 tons of recyclables at the Eco-
Cycle/Broomfield Recycling Center for the month of January 2006 saved the equivalent of
777,910 gallons of water, 1,889 trees, 549,332 kilowatt hours of energy, 6,845 pounds of air
pollutants and 1,473 cubic yards of landfill space. And that was in just one month!
2. Recycling prevents pollution.
When recycled materials are used in place of virgin materials during manufacturing, we avoid
the environmental damage caused by mining for metals, drilling for petroleum, and harvesting
trees. Of course there is always some degree of pollution created in any manufacturing process,
including recycling, but production using recycled material is dramatically less polluting and
resource intensive than production from virgin materials:
• Producing recycled white paper creates 74% less air pollution and 35% less water
pollution than producing paper from virgin fibers.
• Using recycled cans instead of extracting ore to make aluminum cans produces 95% less
air pollution and 97% less water pollution.
• Recycling and remanufacturing are 194 times more effective in reducing greenhouse gas
emissions than landfilling and virgin manufacturing.

3. Recycling saves energy.
Every year, Americans generate more than 230 million tons of solid waste. By recycling about
30% of our waste every year, Americans save the energy equivalent of 11.9 billion gallons of
gasoline and reduce the greenhouse gas equivalent of taking 25 million cars off the road.
For every one million tons of material recycled rather than landfilled, we save the energy
equivalent of
• Aluminum: 35,680,000 barrels of oil
• Glass: 460,000 barrels of oil
• Newspaper: 2,920,000 barrels of oil
• Office paper: 1,760,000 barrels of oil
• Mixed residential paper: 4,010,000 barrels of oil
• PET (plastic): 9,100,000 barrels of oil
• HDPE (plastic): 8,870,000 barrels of oil

The Expert answers:

Requirements at the truck stops and truck service/repair shops regarding Hazardous Waste and environmental liabilities is the same as for auto repair/service shops.
All waste oil must be collected and stored in labeled reservoirs, and tracked to the recycler by licensed hazmat transporters.
Any spill, in either venue must be contained, and recovered by APPROPRIATE means.
Some spills can be recovered with approved absorbent granules such as clay, DRYSORB etc. Others must be controlled and recovered with booms. The EPA is vigilant concerning this issue for all hazmat generators.
This includes other fluids as well such as antifreeze, brake fluid, transmission oils and the like.
In addition to these, the chemicals used in the industry are heavily regulated as well, and they cannot be discarded in trash waste.
Old and contaminated gasoline or diesel must not be mixed with lubricant oil waste.
Coolant must be reclaimed and stored for recycling.
To be sure, there are shops (auto and truck both) that try to cheat the system.
Others err due to ignorance, but the penalties are high, and getting higher.
Loss of license, financial censure and jail time are all penalties suffered for disregarding regulations and laws governing hazardous waste.

Merry Christmas

The Expert answers:

Mother nature, she recycles everything, she takes ground water evaporates it then turns it into fresh water in the form of rain. Insects recycle all waste into nutrients to feed plants, who recycle co2 into oxygen and sunlight into food. You could also say the dinosaurs were recycled into oil.

Modern man has been recycling since the begining of time, unused food into compost, trees into furniture into fire, sand into glass, broken tools were remelted and made into something new.

The idea of throwing things away is pretty new.

The Expert answers:

The oil is decanted into a large holding tank where it is boiled up and left to settle. Any water is removed and the oil is then filtered. This process is repeated to produce a watery brown liquid that is used in furnaces at power stations and quarries as an alternative, recycled fuel

The Expert answers:

Cons – Recycling:
Pollution — how many trucks are on the roads now to collect all of that junk?
-Manufacturing of the truck and all of its parts
-Gas, Oil, Transmission Fluid, Gear Oil, Hydraulic Fluid, Power Steering Fluid, Air Filters, tires (waste)

Pollution — how many blue/green/black containers do we have to manufacture so people can recycle
-Transportation of the containers to houses

Pollution — how many processing centers do we have to build
-Energy draw, tractors moving stuff around, etc. Etc..

Http://www.videosift.com/video/Penn-Teller-Bullshit-Recycling

Daniel Benjamin’s Paper referenced in Penn and Teller:
http://www.environnement-propriete.org/english/2004/2004download_pdf/Benjamin2004.pdf

We have plenty of landfill space — have you seen landfills lately?
-They produce and capture Landfill gasses
http://www.epa.gov/landfill/proj/index.htm
“As of December 2008, approximately 480 landfill gas (LFG) energy projects were operational in the United States. These 480 projects generate approximately 12 billion kilowatt-hours of electricity per year and deliver 255 million cubic feet per day of LFG to direct-use applications. EPA estimates that approximately 520 additional landfills present attractive opportunities for project development.”

-They turn them into fertile parks
http://webecoist.com/2009/05/10/garbage-to-green-10-landfills-turned-into-nature-preserves/

http://answers.yahoo.com/question/index?qid=20081005134527AAvr32j

Google is your friend:
Google Cons Recycling

The Expert answers:

Recycling can be defined as an act of reusing used materials or products by processing them. This helps our environment by reducing the burden on natural resources which are getting depleted significantly. A common example of recyclable items today is paper, which is then converted to new paper products. Glass, tin, wood, etc. Are some of the other items that can be recycled. Recycling is very good for the environment in many ways. Some of these include:
Lowers landfill amount
Too much landfill means a huge problem for mankind and other animal species. Non-biodegradable products accumulated for a long period means harmful and toxic gases. Recycling prevents the same.
Reduces consumption of energy
Natural resources are drying out. This applies for oil, forests, metals, mines, etc. Hence, recycling helps by reusing the resource once again, instead of digging into mother earth for more. It requires lower energy to use recycled wood as it would take many years for a plant to become a full-grown tree.
Reduces pollution
As landfills lead to harmful emission of gases and other toxic wastes they pollute the environment. If you ever pass a landfill during humid and warm summer months you would hate the stench caused due to toxic gases. Recycling helps in reducing the landfill deposits and making the world a better place to live.
Cost-effective
Recycled goods cost less compared to regular items. You can also reduce other costs by recycling methods at home. For instance, use natural rotten veggies or your pet pee can actually be a good fertilizer for the garden. Recycle the grass and leaves to create a compost of them.
It is time to act now. Recycling can help your children breathe fresh air and lead a pollution free life. Ask others to join this quest for recycling and adopt environmental friendly habits.

The Expert answers:

Radioactive waste is waste type containing radioactive chemical elements that does not have a practical purpose. It is sometimes the product of a nuclear process, such as nuclear fission. The majority of radioactive waste is “low-level waste”, meaning it has low levels of radioactivity per mass or volume. This type of waste often consists of items such as used protective clothing, which is only slightly contaminated but still dangerous in case of radioactive contamination of a human body through ingestion, inhalation, absorption, or injection.

[edit] Sources of waste

[edit] NORM (naturally occurring radioactive material)
Processing of substances containing natural radioactivity, this is often known as NORM. Much of this waste is alpha particles emitting matter from the decay chains of uranium and thorium.

[edit] Coal
Coal contains a small amount of radioactive nuclides, such as uranium and thorium, but it is less than the average concentration of those elements in the Earth’s crust. They become more concentrated in the fly ash because they do not burn well [1]. However, the radioactivity of fly ash is still very low. It is about the same as black shale and is less than phosphate rocks, but is more of a concern because a small amount of the fly ash ends up in the atmosphere where it can be inhaled.[2].

[edit] Oil and gas
Residues from the oil and gas industry often contain radium and its daughters. The sulphate scale from an oil well can be very radium rich, while the water, oil and gas from a well often contains radon. The radon decays to form solid radioisotopes which form coatings on the inside of pipework. In an oil processing plant the area of the plant where propane is processed is often one of the more contaminated areas of the plant as radon has a similar boiling point as propane.[1]

[edit] Mineral processing
Wastes from mineral processing can contain natural radioactivity.

[edit] Medical
Radioactive medical waste tends to contain beta ray and gamma ray emitters. It can be divided into two main classes. In diagnostic nuclear medicine a number of short-lived gamma emitters such as Tc-99m are used. Many of these can be disposed of by leaving it to decay for a short time before disposal as normal trash. Other isotopes used in medicine, with half-lives in parentheses:

Y-90, used for treating lymphoma (2.7 days)
I-131, used for thyroid function tests and for treating thyroid cancer (8.0 days)
Sr-89, used for treating bone cancer, intravenous injection (52 days)
Ir-192, used for brachytherapy (74 days)
Co-60, used for brachytherapy and external radiotherapy (5.3 years)
Cs-137, used for brachytherapy, external radiotherapy (30 years)

[edit] Industrial
Industrial source waste can contain alpha, beta, neutron or gamma emitters. Gamma emitters are used in radiography while neutron emitting sources are used in a range of applications, such as oil well logging.[3]

[edit] Nuclear fuel cycle
Main articles: Nuclear fuel cycle and Used nuclear fuel

[edit] Front end
Waste from the front end of the nuclear fuel cycle is usually alpha emitting waste from the extraction of uranium. It often contains radium and its decay products.

Uranium dioxide (UO2) concentrate from mining is not very radioactive – only a thousand or so times as radioactive as the granite used in buildings. It is refined from yellowcake (U3O8), then converted to uranium hexafluoride gas (UF6). As a gas, it undergoes enrichment to increase the U-235 content from 0.7% to about 3.5% (LEU). It is then turned into a hard ceramic oxide (UO2) for assembly as reactor fuel elements.

The main by-product of enrichment is depleted uranium (DU), principally the U-238 isotope, with a U-235 content of ~0.3%. It is stored, either as UF6 or as U3O8. Some is used in applications where its extremely high density makes it valuable, such as the keels of yachts, and anti-tank shells. It is also used (with recycled plutonium) for making mixed oxide fuel (MOX) and to dilute highly enriched uranium from weapons stockpiles which is now being redirected to become reactor fuel. This dilution, also called downblending, means that any nation or group that acquired the finished fuel would have to repeat the (very expensive and complex) enrichment process before assembling a weapon.

[edit] Back end
The back end of the nuclear fuel cycle, mostly spent fuel rods, often contains fission products that emit beta and gamma radiation, and may contain actinides that emit alpha particles, such as uranium-234, neptunium-237, plutonium-238 and americium-241, and even sometimes some neutron emitters such as Cf. These isotopes are formed in nuclear reactors.

It is important to distinguish the processing of uranium to make fuel from the reprocessing of used fuel. Used fuel contains the highly radioactive products of fission (see High Level Waste below). Many of these are neutron absorbers called neutron poisons in this context. These eventually build up to a level where they absorb so many neutrons that the chain reaction stops, even with the control rods completely removed. At that point the fuel has to be replaced in the reactor with fresh fuel, even though there is still a substantial quantity of uranium-235 and plutonium present. Currently, in the USA, this used fuel is stored. In other countries (the UK, France, and Japan in particular) the fuel is reprocessed to remove the fission products, and the fuel can then be re-used. The reprocessing process involves handling highly radioactive materials, and the fission products removed from the fuel are a concentrated form of High Level Waste as are the chemicals used in the process.

[edit] Proliferation concerns
Main article: nuclear proliferation
When dealing with uranium and plutonium, the possibility that they may be used to build nuclear weapons is often a concern. Active nuclear reactors and nuclear weapons stockpiles are very carefully safeguarded and controlled. However, high-level waste from nuclear reactors may contain plutonium. Ordinarily, this plutonium is reactor-grade plutonium, containing a mixture of plutonium-239 (highly suitable for building nuclear weapons) and plutonium-240 (an undesirable contaminant and highly radioactive); the two isotopes are difficult to separate. Moreover, high-level waste is full of highly radioactive fission products. However, most fission products are relatively short-lived. This is a concern since if the waste is stored, perhaps in deep geological storage, over many years the fission products decay, decreasing the radioactivity of the waste and making the plutonium easier to access. Moreover, the undesirable contaminant Pu-240 decays faster than the Pu-239, and thus the quality of the bomb material increases with time (although its quantity decreases). Thus, some have argued, as time passes, these deep storage areas have the potential to become “plutonium mines”, from which material for nuclear weapons can be acquired with relatively little difficulty. Critics of the latter idea point out that the half-life of Pu-240 is 6,560 years and Pu-239 is 24,110 years, and thus the relative enrichment of one isotope to the other with time occurs with a half-life of 9,000 years (that is, it takes 9000 years for the fraction of Pu-240 in a sample of mixed plutonium isotopes, to spontaneously decrease by half– a typical enrichment needed to turn reactor-grade into weapons-grade Pu). Thus “weapons grade plutonium mines” would be a problem for the very far future (>9,000 years from now), so that there remains a great deal of time for technology to advance to solve this problem, before it becomes acute.

Pu-239 decays to U-235 which is suitable for weapons and which has a very long half life (roughly 109 years). Thus plutonium may decay and leave uranium-235. However, modern reactors are only moderately enriched with U-235 relative to U-238, so the U-238 continues to to serve as denaturation agent for any U-235 produced by plutonium decay.

One solution to this problem is to recycle the plutonium and use it as a fuel e.g. In fast reactors. But the very existence of the nuclear fuel reprocessing plant needed to separate the plutonium from the other elements represents, in the minds of some, a proliferation concern. In pyrometallurgical fast reactors, the waste generated is an actinide compound that cannot be used for nuclear weapons.

[edit] Nuclear weapons reprocessing
Waste from nuclear weapons reprocessing (as opposed to production, which requires primary processing from reactor fuel) is unlikely to contain much beta or gamma activity other than tritium and americium. It is more likely to contain alpha emitting actinides such as Pu-239 which is a fissile material used in bombs, plus some material with much higher specific activities, such as Pu-238 or Po.

In the past the neutron trigger for a bomb tended to be beryllium and a high activity alpha emitter such as polonium, an alternative to polonium is Pu-238. For reasons of national security, details of the design of modern bombs are normally not released to the open literature. It is likely however that a D-T fusion reaction in either an electrically driven device or a D-T fusion reaction driven by the chemical explosives would be used to start up a modern device.

Some designs might well contain a RTG using Pu-238 to provide a longlasting source of electrical power for the electronics in the device.

It is likely that the fissile material of an old bomb which is due for refitting will contain decay products of the plutonium isotopes used in it, these are likely to include alpha-emitting Np-236 from Pu-240 impurities, plus some U-235 from decay of the Pu-239; however, due to the relatively long half-life of these Pu isotopes, these wastes from radioactive decay of bomb core material would be very small, and in any case, far less dangerous (even in terms of simple radioactivity) than the Pu-239 itself.

The beta decay of Pu-241 forms Am-241, the in-growth of americium is likely to be a greater problem than the decay of Pu-239 and Pu-240 as the americium is a gamma emitter (increasing external-exposure to workers) and is an alpha emitter which can cause the generation of heat. The plutonium could be separated from the americium by several different processes, these would include pyrochemical processes and aqueous/organic solvent extraction. A truncated PUREX type extraction process would be one possible method of making the separation.

[edit] Basic overview

[edit] Physics
The radioactivity of all nuclear waste diminishes with time. All radioisotopes contained in the waste have a half-life – the time it takes for any radionuclide to lose half of its radioactivity and eventually all radioactive waste decays into non-radioactive elements. Certain radioactive elements (such as plutonium-239) in “spent” fuel will remain hazardous to humans and other living beings for hundreds of thousands of years. Other radioisotopes will remain hazardous for millions of years. Thus, these wastes must be shielded for centuries and isolated from the living environment for hundreds of millennia [4]. Some elements, such as I-131, have a short half-life (around 8 days in this case) and thus they will cease to be a problem much more quickly than other, longer-lived, decay products but their activity is much greater initially.

The faster a radioisotope decays, the more radioactive it will be. The energy and the type of the ionizing radiation emitted by a pure radioactive substance are important factors in deciding how dangerous it will be. The chemical properties of the radioactive element will determine how mobile the substance is and how likely it is to spread into the environment and contaminate human bodies. This is further complicated by the fact that many radioisotopes do not decay immediately to a stable state but rather to a radioactive decay product leading to decay chains.

[edit] Biochemistry
Depending on the decay mode and the biochemistry of an element, the threat due to exposure to a given activity of a radioisotope will differ. For instance I-131 is a short-lived beta and gamma emitter but because it concentrates in the thyroid gland, it is more able to cause injury than TcO4- which, being water soluble, is rapidly excreted in urine. In a similar way, the alpha emitting actinides and radium are considered very harmful as they tend to have long biological half-lives and their radiation has a high linear energy transfer value. Because of such differences, the rules determining biological injury differ widely according to the radioisotope, and sometimes also the nature of the chemical compound which contains the radioisotope.

[edit] Philosophy
The main objective in managing and disposing of radioactive (or other) waste is to protect people and the environment. This means isolating or diluting the waste so that the rate or concentration of any radionuclides returned to the biosphere is harmless. To achieve this the preferred technology to date has been deep and secure burial for the more dangerous wastes; transmutation, long-term retrievable storage, and removal to space have also been suggested.

The phrase which sums up the area is ‘ Isolate from man and his environment ‘ until the waste has decayed such that it no longer poses a threat.

[edit] Fiction
In fiction, radioactive waste is often cited as the reason for gaining super-human powers and abilities. An example of this fictional scenario is the 1981 movie “Modern Problems” in which actor Chevy Chase portrays a jealous, harried air traffic controller Max Fiedler; Max Fiedler, recently dumped by his girlfriend, comes into contact with nuclear waste and is granted the power of telekinesis, which he uses to not only win her back, but to gain a little revenge. Another more widely known character affected by a bite from a radioactive spider is Spider-man. The Spider-man character was developed by Marvel Comics (see also Stan Lee) and was portrayed on the big screen by actor Tobey Macguire in two films: the first in 2002, and the second in 2004. In the film franchise, however, it is a bioengineered spider that bites him and changes his genetic makeup.

In reality, exposure to high levels of radioactive waste may cause serious harm or death. It is interesting to note that the treatment of an adult animal with radiation or some other mutation causing effect, such as a cytotoxic anti-cancer drug, cannot cause that adult animal to become a mutant. It is more likely that a cancer will be induced in the animal. In humans it has been calculated that a 1 sievert dose has a 5% chance of causing cancer and a 1% chance of causing a mutation in a gamete (e.g. Egg) or a gamete forming cell such as those in the testis which can be passed to the next generation. If a developing organism such as an unborn child is irradiated, then it is possible to induce a birth defect but it is unlikely that this defect will be in a gamete or a gamete forming cell.

[edit] Types of radioactive waste

Removal of very low-level wasteAlthough not significantly radioactive, uranium mill tailings are waste. They are byproduct material from the rough processing of uranium-bearing ore. They are sometimes referred to as 11(e)2 wastes, from the section of the U.S. Atomic Energy Act that defines them. Uranium mill tailings typically also contain chemically-hazardous heavy metals such as lead and arsenic. Vast mounds of uranium mill tailings are left at many old mining sites, especially in Colorado, New Mexico, and Utah.

Low Level Waste (LLW) is generated from hospitals and industry, as well as the nuclear fuel cycle. It comprises paper, rags, tools, clothing, filters, etc., which contain small amounts of mostly short-lived radioactivity. Commonly, LLW waste is designated as such as a precautionary measure if it originated from any region of an ‘Active Area’, which frequently includes offices with only a remote possibility of being contaminated with radioactive materials. Such LLW waste typically exhibits no higher radioactivity than one would expect from the same material disposed of in a non-active area, such as a normal office block. No LLW waste requires shielding during handling and transport and is suitable for shallow land burial. To reduce its volume, it is often compacted or incinerated before disposal. Low level waste is divided into four classes, class A, B, C and GTCC, which means “Greater Than Class C”.

Intermediate Level Waste (ILW) contains higher amounts of radioactivity and in some cases requires shielding. ILW includes resins, chemical sludge and metal reactor fuel cladding, as well as contaminated materials from reactor decommissioning. It may be solidified in concrete or bitumen for disposal. As a general rule, short-lived waste (mainly non-fuel materials from reactors) is buried in shallow repositories, while long-lived waste (from fuel and fuel-reprocessing) is deposited in deep underground facilities. U.S. Regulations do not define this category of waste; the term is used in Europe and elsewhere.

High Level Waste flasks are transported by train in the United Kingdom. Each flask is constructed of 3ft thick solid steel and weighs in excess of 50 tonsHigh Level Waste (HLW) is produced by nuclear reactors. It contains fission products and transuranic elements generated in the reactor core. It is highly radioactive and often thermally hot. HLW accounts for over 95% of the total radioactivity produced in the process of nuclear electricity generation.

Transuranic Waste (TRUW) as defined by U.S. Regulations is, without regard to form or origin, waste that is contaminated with alpha-emitting transuranic radionuclides with half-lives greater than 20 years, and concentrations greater than 100 nCi/g (3.7 MBq/kg), excluding High Level Waste. Elements that have an atomic number greater than uranium are called transuranic (“beyond uranium”). Because of their long half-lives, TRUW is disposed more cautiously than either low level or intermediate level waste. In the U.S. It arises mainly from weapons production, and consists of clothing, tools, rags, residues, debris and other items contaminated with small amounts of radioactive elements (mainly plutonium).

Under U.S. Law, TRUW is further categorized into “contact-handled” (CH) and “remote-handled” (RH) on the basis of radiation dose measured at the surface of the waste container. CH TRUW has a surface dose rate not greater than 200 mrem per hour (2 mSv/h), whereas RH TRUW has a surface dose rate of 200 mrem per hour (2 mSv/h) or greater. CH TRUW does not have the very high radioactivity of high level waste, nor its high heat generation, but RH TRUW can be highly radioactive, with surface dose rates up to 1000 rem per hour (10 mSv/h). The United States currently permanently disposes of TRUW generated from nuclear power plants and military facilities at the Waste Isolation Pilot Plant.[2]

[edit] Management of medium level waste
It is common for medium active wastes in the nuclear industry to be treated with ion exchange or other means to concentrate the radioactivity into a small volume. The much less radioactive bulk (after treatment) is often then discharged. For instance, it is possible to use a ferric hydroxide floc to remove radioactive metals from aqueous mixtures [5]. After the radioisotopes are absorbed onto the ferric hydroxide, the resulting sludge can be placed in a metal drum before being mixed with cement to form a solid waste form.[3] In order to get better long-term performance (mechanical stability) from such forms, they may be made from a mixture of fly ash, or blast furnace slag, and portland cement, instead of the normal cement (made with portland cement, gravel and sand).

[edit] Management of high level waste

[edit] Storage
High-level radioactive waste is stored temporarily in spent fuel pools and in dry cask storage facilities. This allows the shorter-lived isotopes to decay before further handling.

Long-term storage of radioactive waste requires the stabilization of the waste into a form which will not react, nor degrade, for extended periods of time. One way to do this is through vitrification. Currently at Sellafield, the high-level waste (PUREX first cycle raffinate) is mixed with sugar and then calcined. Calcination involves passing the waste through a heated, rotating tube. The purposes of calcination are to evaporate the water from the waste, and de-nitrate the fission products to assist the stability of the glass produced.

The ‘Calcine’ generated is fed continuously into an induction heated furnace with fragmented glass[6]. The resulting glass is a new subtance in which the waste products are bonded into the glass matrix when it solidifies. This product, as a molten fluid, is poured into stainless steel cylindrical containers (“cylinders”) in a batch process. When cooled, the fluid solidifies (“vitrifies”) into the glass. Such glass, after being formed, is very highly resistant to water. [7] According to the ITU, it will require about 1 million years for 10% of such glass to dissolve in water.

After filling a cylinder, a seal is welded onto the cylinder. The cylinder is then washed. After being inspected for external contamination, the steel cylinder is stored, usually in an underground repository. In this form, the waste products are expected to be immobilised for a very long period of time (many thousands of years).

The glass inside a cylinder is usually a black glossy substance. All this work (in the United Kingdom) is done using hot cell systems. The sugar is added to control the ruthenium chemistry and to stop the formation of the volatile RuO4 containing radioruthenium. In the west, the glass is normally a borosilicate glass (similar to Pyrex {NB Pyrex is a trade name}), while in the former Soviet bloc it is normal to use a phosphate glass. The amount of fission products in the glass must be limited because some (palladium, the other Pt group metals, and tellurium) tend to form metallic phases which separate from the glass. In Germany a vitrification plant is in use; this is treating the waste from a small demonstration reprocessing plant which has since been closed down.

In 1997, in the 20 countries which account for most of the world’s nuclear power generation, spent fuel storage capacity at the reactors was 148,000 tonnes, with 59% of this utilized. Away-from-reactor storage capacity was 78,000 tonnes, with 44% utilized. With annual additions of about 12,000 tonnes, issues for final disposal are not urgent.

In 1989 and 1992, France commissioned commercial plants to vitrify HLW left over from reprocessing oxide fuel, although there are adequate facilities elsewhere, notably in the United Kingdom and Belgium. The capacity of these western European plants is 2,500 canisters (1000 t) a year, and some have been operating for 18 years.

[edit] Synroc
The Australian Synroc (synthetic rock)[8] is a more sophisticated way to immobilize such waste, and this process may eventually come into commercial use for civil wastes (it is currently being developed for US military wastes). The synroc contains pyrochlore and cryptomelane type minerals. The original form of synroc (synroc C) was designed for the liquid high level waste (PUREX raffinate) from a light water reactor. The main minerals in this synroc are hollandite (BaAl2Ti6O16), zirconolite (CaZrTi2O7) and perovskite (CaTiO3). The zirconolite and perovskite are hosts for the actinides. The strontium and barium will be fixed in the perovskite. The cesium will be fixed in the hollandite.

Synroc was invented by the late Prof Ted Ringwood (a geochemist) at the Australian National University.

Nuclear waste locations in USA
[edit] Geological disposal
The process of selecting appropriate deep final repositories is now under way in several countries with the first expected to be commissioned some time after 2010.However, many people remain uncomfortable with the immediate stewardship cessation of this management system. In Switzerland, the Grimsel Test Site is an international research facility investigating the open questions in radioactive waste disposal ([9]). Sweden is well advanced with plans for direct disposal of spent fuel, since its Parliament decided that this is acceptably safe, using the KBS-3 technology. In Germany, there is a political discussion about the search for an Endlager (final repository) for radioactive waste, accompanied by loud protests especially in the Gorleben village in the Wendland area, which was seen ideal for the final repository until 1990 because of its location next to the border to the former German Democratic Republic. Gorleben is presently being used to store radioactive waste non-permanently, with a decision on final disposal to be made at some future time. The U.S. Has opted for a final repository at Yucca Mountain in Nevada, but this project is widely opposed and is a hotly debated topic. There is also a proposal for an international HLW repository in optimum geology, with Australia or Russia as possible locations, although the proposal for a global repository for Australia has raised fierce domestic political objections.

Sea-based options for disposal of radioactive waste [10] include burial beneath a stable abyssal plain, burial in a subduction zone that would slowly carry the waste downward into the Earth’s mantle, and burial beneath a remote natural or human-made island. While these approaches all have merit and would facilitate an international solution to the vexing problem of disposal of radioactive waste, they are currently not being seriously considered because of the legal barrier of the Law of the Sea and because in North America and Europe sea-based burial has become taboo from fear that such a repository could leak and cause widespread damage, though the evidence that this would happen is lacking. Dumping of radioactive waste from ships has reinforced this taboo. However, sea-based approaches might come under consideration in the future by individual countries or groups of countries that cannot find other acceptable solutions.

A more feasible approach termed Remix & Return [11] would blend high-level waste with uranium mine and mill tailings down to the level of the original radioactivity of the uranium ore, then replace it in empty uranium mines. This approach has the merits of totally eliminating the problem of high-level waste, of placing the material back where it belongs in the natural order of things, of providing jobs for miners who would double as disposal staff, and of facilitating a cradle-to-grave cycle for all radioactive materials.

[edit] Transmutation
There have been proposals for reactors that consume nuclear waste and transmute it to other, less-harmful nuclear waste. In particular, the Integral Fast Reactor was a proposed nuclear reactor with a nuclear fuel cycle that produced no transuranic waste and in fact, could consume transuranic waste. It proceeded as far as large-scale tests but was then cancelled by the US Government. Another approach, considered safer but requiring more development, is to dedicate subcritical reactors to the transmutation of the left-over transuranic elements.

There have also been theoretical studies involving the use of fusion reactors as so called “actinide burners” where a fusion reactor plasma such as in a tokamak, could be “doped” with a small amount of the “minor” transuranic atoms which would be transmuted to lighter elements upon their successive bombardment by the very high energy neutrons produced by the fusion of deuterium and tritium in the reactor. It was recently found by a study done at MIT, that only 2 or 3 fusion reactors with parameters similar to that of the International Thermonuclear Experimental Reactor (ITER) could transmute the entire annual actinide production from all of the light water reactors presently operating in the United States fleet while simultaneously generating approximately 1 gigawatt of power from each reactor.

[edit] Reuse of waste
Another option is to find applications of the isotopes in nuclear waste so as to reuse them. [12] . Already, cesium 137, strontium 90 and a few other isotopes are extracted for certain industrial applications such as food irradiation and RTGs.

[edit] Space disposal
Space disposal is an attractive notion because it permanently removes nuclear waste from the environment. However, it has significant disadvantages, not least of which is the potential for catastrophic failure of a launch vehicle. Furthermore, the high number of launches that would be required makes the proposal impractical. To further complicate matters, international agreements on the regulation of a such a program would need to be established.[13]

[edit] Accidents involving radioactive waste
While radioactive waste is not as sensitive to disruption as an active nuclear reactor, it is often treated as regular waste and forgotten. A number of incidents have occurred when radioactive material was disposed of improperly, simply abandoned or even stolen from a waste store.

Scavenging of abandoned radioactive material has been the cause of several other cases of radiation exposure, mostly in developing nations, which usually have less regulation of dangerous substances (and sometimes less general education about radioactivity and its hazards) and a market for scavenged goods and scrap metal. The scavengers and those who buy the material are almost always unaware that the material is radioactive and it is selected for its aesthetics or scrap value. A few are aware of the radioactivity, but are either ignorant of the risk or believe that the material’s value outweighs the danger. Irresponsibility on the part of the radioactive material’s owners, usually a hospital, university or military, and the absence of regulation concerning radioactive waste, or a lack of enforcement of such regulations, have been significant factors in radiation exposures. For details of radioactive scrap see the Goiânia accident.

Transportation accidents involving spent nuclear fuel from power plants are unlikely to have serious consequences due to the strength of the spent nuclear fuel shipping casks.

[edit] See also
Global Nuclear Energy Partnership
Hot cell
List of nuclear accidents
Nuclear power
Stored Waste Examination Pilot Plant
Geomelting
Radioactive scrap metal

[edit] References
^ Survey & Identification of NORM Contaminated Equipment
^ Why WIPP?
^ Removal of Silicon from High Level Waste Streams via Ferric Flocculation
Fentiman, Audeen W. And James H. Saling. Radioactive Waste Management. New York: Taylor & Francis, 2002. Second ed. An overview of waste from the nuclear fuel cycle was written by B.V. Babu and S. Karthik, Energy Education Science and Technology, 2005, 14, 93-102.

[edit] External links
Key Radionuclides and Generation Processes (DOE)
Alsos Digital Library – Radioactive Waste (bibliography)
Belgian Nuclear Research Centre – Activities (documents and links)
Belgian Nuclear Research Centre – Scientific Reports (documents)
Critical Hour: Three Mile Island, The Nuclear Legacy, And National Security (PDF)
Environmental Protection Agency – Yucca Mountain (documents)
Grist.org – How to tell future generations about nuclear waste (article)
A discussion on the secrecy surrounding plans for radioactive waste in the UK (article)
International Atomic Energy Agency – Nuclear Fuel Cycle and Waste Technology Program (program objectives)
International Atomic Energy Agency – Internet Directory of Nuclear Resources (links)
Nuclear Files.org – Yucca Mountain (documents)
Nuclear Regulatory Commission – Radioactive Waste (documents)
Nuclear Regulatory Commission – Spent Fuel Heat Generation Calculation (guide)
Oak Ridge National Laboratory – Coal Combustion: Nuclear Resource or Danger (document)
Radwaste.org (links)
Radwaste Blog (weblog)
Surviving on Nuclear Waste (book)
The Nuclear Energy Option – Hazards of High-Level Radioactive Waste (book)
UNEP Earthwatch – Radioactive Waste (documents and links)
Uranium Information Center – Radioactive Waste (briefing papers)
United States Geological Survey – Radioactive Elements in Coal and Fly Ash (document)
World Nuclear Association – Radioactive Waste (briefing papers)
Radioactive Waste Management, by UIC

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