Environmental issues

Environmental issues are harmful effects of human activity on the biophysical environment. Environmental protection is a practice of protecting the natural environment on individual, organizational or governmental levels, for the benefit of both the environment and humans.

The main environmental problems:

1. Air pollution and climate change.

Overloading of the atmosphere and of ocean waters with carbon. Atmospheric CO2 absorbs and re-emits infrared-wavelength radiation, leading to warmer air, soils, and ocean surface waters - which is good: The planet would be frozen solid without this.

Unfortunately, there's now too much carbon in the air. Burning of fossil fuels, deforestation for agriculture, and industrial activities have increased atmospheric CO2 concentration and led to climate disruption.

Carbon overloading is only one form of air pollution caused by burning coal, oil, gas and wood. The World Health Organization recently estimated that one in nine deaths in 2012 were caused by carcinogens and other poisons in polluted air.

2. Deforestation.

Our woodlands create new oxygen and additionally help in managing temperature and precipitation. Species-rich wild forests are being destroyed, especially in the tropics, often to make way for cattle ranching, soybean or palm oil plantations, or other agricultural monocultures.

Today, about 30 percent of the planet's land area is covered by forests - which is about half as much as before agriculture got started around 11,000 years ago. Tropical forests used to cover about 15 percent of the planet's land area; they're now down to 6 or 7 per cent.

Not only do natural forests act as biodiversity reserves, they are also carbon sinks, keeping carbon out of the atmosphere and oceans.

3. Water Pollution: 

Clean drinking water is turning into an uncommon thing. Water is turning into a monetary and political concern. Waste from industrial and agricultural activities pollute the water that is used by humans, animals and plants.

4: Soil and Land Pollution: 

Land pollution simply means degradation of earth’s surface as a result of human activities like mining, littering, deforestation, industrial, construction and agricultural activities. Land pollution can have huge environmental impact in the form of air pollution and soil pollution which in turn can have adverse effect on human health.

5. Effect on Marine Life: 

The amount of carbon in the water and the atmosphere is continuing to be a problem in the world around us. The primary effect is on shellfish and microscopic fish, and it has similar effects to osteoporosis in humans.

6: Loss of Biodiversity: 

Biodiversity is yet another casualty due to the impact of human beings on the environment. It is the result of 3.5 billion years of evolution. Habitat destruction is a major cause for biodiversity loss. Habitat loss is caused by deforestation, overpopulation, pollution and global warming..

7. Ozone Layer Depletion: 

The ozone layer is an undetectable layer of protection around the planet that secures us from the sun’s unsafe beams. Depletion of the critical Ozone layer of the air is credited to contamination brought about by Bromide and Chlorine ( Cl)  found in Chlorofloro carbons. When these poisonous gasses each the upper parts of the atmosphere, they cause a gap in the ozone layer, the greatest of which is over the Antarctic.

8. Mining: 

Mining results in extraction of minerals from earth’s core. These minerals also bring out harmful chemicals from deep inside the earth to the earth’s surface. The toxic emissions from mining can cause air, water and soil pollution.

9: Natural Resource Depletion:

 Non-renewable resources are limited and will get expired one day. Consumption of fossil fuels at an alarming rate can lead to global warming which can further result in melting of polar ice caps and increase in sea levels.

10: Nuclear Issues:

 Radioactive waste is a nuclear fuel that contains radioactive substance and is a by-product of nuclear power generation. The radioactive waste is an environmental concern that is extremely toxic and can have devastating effect on the lives of the people living nearby, if not disposed properly. Radioactive waste is considered to be harmful for humans, plants, animals and surrounding environment.

11. Acid Rain:

 Acid rain happens because of the vicinity of specific poisons in the climate. Corrosive downpour might be brought about because of use of fossil fuels or volcanoes or spoiling vegetation which discharge sulfur dioxide and nitrogen oxides into the air.

12: Agricultural Pollution:

 Modern day agriculture practices make use of chemical products like pesticides and fertilizers to deal with local pests. Some of the chemicals when sprayed do not disappear and in fact seep into the ground and thereby harm plants and crops. Also, contaminated water is used for irrigation by farmers.

13: Littering and Landfills:

 Littering simply means disposal of piece of garbage or debris improperly or at wrong location usually on the ground instead of  disposing them at trash container or recycling bin. Littering can cause huge environmental and economic impact in the form of spending millions of dollars to clean the garbage of road that pollute the clean air. Landfills on the other hand are nothing but huge garbage dumps that make the city look ugly and produce toxic gases that could prove fatal for humans and animals. Landfills are generated due to large amount of waste that is generated by households, industries and healthcare centers everyday.

So, let’s look into the problem of nuclear waste

The challenge of making nuclear power safer doesn't end after the power has been generated. Nuclear fuel remains dangerously radioactive for thousands of years after it is no longer useful in a commercial reactor. The resulting waste disposal problem has become a major challenge for policymakers.

 The dilemma of how to manage nuclear waste – radioactive materials routinely produced in large quantities at every stage of nuclear power production, from uranium mining and enrichment to reactor operation and the reprocessing of spent fuel – has taxed the industry, academics and governments for decades.

Depending on how countries classify waste, only about 0.2–3% by volume is high-level waste, according to the World Nuclear Association (WNA), a London-based industry group that promotes nuclear power.

Mostly derived from civil reactor fuel, this is some of the most dangerous material known on Earth, remaining radioactive for tens of thousands of years. It requires cooling and shielding indefinitely and contains 95% of the radioactivity related to nuclear power generation.

A further 7% or so by volume, known as intermediate waste, is made up of things such as reactor components and graphite from reactor cores. This is also highly dangerous, but it can be stored in special canisters because it does not generate much heat.

The rest is made up of vast quantities of what is called low-level and very low-level waste. This comprises scrap metal, paper, plastics, building materials and everything else radioactive involved in the operation and dismantling of nuclear facilities.

The consensus is that about 22,000 cubic metres of solid high-level waste has accumulated in temporary storage but not been disposed of (moved to permanent storage) in 14 western countries, along with unknown amounts in China, Russia and at military stations.

Although it is impossible to come up with a global total because of differences in how quantities are measured and reported, and with some inventories kept secret, other countries harbour significant amounts of waste as well.

Safer storage of spent nuclear fuel

Until permanent repository storage is available, spent nuclear fuel should be stored in dry casks, not overcrowded pools. Dry casks are a near-term solution. Spent fuel pools at nuclear power plants, intended to house nuclear waste only until it is cool enough to be transferred to permanent storage, have become dangerously overcrowded as the search for a permanent repository has stalled.

Reprocessing isn't a solution

Some experts consider reprocessing as a partial solution to the nuclear waste issue. Reprocessing separates nuclear waste into component materials, including plutonium, which can then be re-used as nuclear reactor fuel—but also as the raw material for a nuclear weapon.

 Possible solutions to this problem

In the early days of nuclear power, waste of any sort was barely considered. British, American and Russian authorities, among others, dumped nuclear waste – including more than 150,000 tonnes of low-level waste – at sea or in rivers. Since then, billions have been spent trying to identify how best to reduce the amount produced and then store it for what may be eternity.

Many ideas have been investigated, but most have been rejected as impractical, too expensive or ecologically unacceptable. They include: shooting it into space; isolating it in synthetic rock; burying it in ice sheets; dumping it on the world’s most isolated islands; and dropping it to the bottom of the world’s deepest oceanic trenches.

Vertical boreholes up to 5,000 metres deep have also been proposed, and this option is said by some scientists to be promising. But there have been doubts, because it is likely to be nearly impossible to retrieve waste from vertical boreholes.

Two scientific developments excite nuclear scientists. One is to build a new generation of advanced fast neutron reactors, which would use the high-level waste as fuel. This slowly emerging “Generation IV” nuclear power programme is billed by the industry as safer and more efficient. But even though such reactors can reduce the degree of hazard the waste poses, they do not solve the issue entirely.

The other technology that could reduce waste, known as transmutation, aims to reduce radiotoxicity by using lasers to change the composition of dangerous waste. It has been investigated for decades in the UK, US, Sweden and elsewhere but without great success.

But the idea was boosted in December 2018 by French Nobel prize–winning physicist Gérard Mourou (Жера́р Муру́), who, in his acceptance lecture, said laser beams millions of times brighter than the surface of the sun in bursts that last a millionth of a billionth of a second had the potential to neutralize nuclear waste, reducing its half-life to a few years and its radioactivity to very little.

“Nuclear energy may be the best candidate for the future, but we are still left with a lot of dangerous junk. The idea is to transmute this nuclear waste into new forms of atoms which don’t have the problem of radioactivity. What you have to do is to change the makeup of the nucleus,” he said in the lecture.

But Mourou accepted that it might take decades before this “extreme light” solution could be deployed to destroy nuclear waste on an industrial scale.

‘No reliable method’

After decades of civil nuclear power and billions spent researching different geological sites and ways to best dispose of the waste, the problems are both technical and political, and the consensus of governments and industry is that deep burial is the best solution – at least for the moment.

Yet, so far, no country has managed to build a deep repository for high-level waste.

Painfully slow

Political and community opposition to plans has made progress painfully slow in most countries. In the UK, the government has offered communities money, but has been unable to persuade any local authority to host a permanent deep repository.

 “The problem is intractable,” says Paul Dorfman, founder of the Nuclear Consulting Group, made up of about 120 international academics and independent experts in the fields of radiation waste, nuclear policy and environmental risk.

“The bitter reality is that there is no scientifically proven way of disposing of the existential problem of high- and intermediate-level waste. Some countries have built repositories, some plan them.

“But given the huge technical uncertainties, if disposal does go ahead and anything goes wrong underground in the next millennia, then future generations risk profound widespread pollution.”

Many people now doubt that a satisfactory final repository will ever be found.

Managing the nuclear legacy is not just a technical issue but a social one.

“The truth is that whatever efforts are made to bury and forget it, it will not go away. For the foreseeable future, the future is the safe and secure storage that is already in situ [at nuclear plants]. In the longer term, better options may materialise.

A new method to help solve the problem of nuclear waste

In the last decades, nanomaterials have gained broad scientific and technological interest due to their unusual properties compared to micrometre-sized materials. At this scale, matter shows properties governed by size. At the present time, nanomaterials are studied to be employed in many different fields, including the nuclear one. Thus, nuclear fuels production, structural materials, separation techniques and waste management, all may benefit from an excellent knowledge in the nano-nuclear technology. No wonder researchers are on the constant lookout for better ways to improve their production.

Scientists from Joint Research Center have come up with a way to do just that. Olaf Walter, Karin Popa and Oliver Dieste Blanco, have devised a simple access to produce highly crystalline, reactive actinide oxide nanocrystals. The shape of the crystals, together with their increased reactivity, enables the consolidation of homogeneous nanostructured mixed oxides as intermediates towards very dense nuclear fuels for advanced reactors. Moreover, such materials can be used as precursors for the production of compounds with special properties, which mimic structures those are found in spent nuclear fuel, and will also be of great use in the study of how such radioactive material migrates in nearby geological environments.

This also may help make the future brighter for nuclear, as a carbon-free energy source.

To sum up, storing of nuclear waste is an international concern which increases with the growth of nuclear power industry. Storing waste in a proper way like deep burial significantly reduces the degree of hazard it poses, however can not be considered the best possible solution to the problem. Scientists and researchers still have to come up with some practical ways to solve it.

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