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Atomic power and the waste 

Fatema Miah:

As I wrote in the previous article With all the master minded mechanism and production we are one of the top  developed status Nations. With the same wow factors of advancement, simultaneously, we are responsible stakeholders for our environmental, ecological, atmospheric climatic conditions.
The favoured option for nuclear waste management around the world at the moment, 2015, is to bury the waste in purpose-built underground repositories. The siting of such a repository requires much thought as many of the fission products will remain active for thousands of years. Thus, a repository needs to be secure, both now and into the far flung future!
There are two main issues that need to be considered. The possibility of seismic activity. Earthquakes could bring the material to the surface. The problem of water. It is vital that water is not able to come in contact with the radioactive material now or in the future. In order to reduce the possibility of either of these problems arising, the design of repositories includes containers with multiple layers enclosing the waste and other engineered barriers or seals around the containers. Great attention is also paid to the suitability of the surrounding environment, particularly the geology in terms of stability and rock composition, and the way water can move through it. Several processes combine to cycle water globally, and these are summarised below.
At any stage in the water cycle where evaporation occurs, anything dissolved in the water is left behind. In particular, radioisotopes transported into the oceans would accumulate there; they would not evaporate and re-enter the water cycle. How water flows through the ground is largely determined by the geology. Many of the rocks that make up the Earth’s crust contain voids, which can hold water. These voids can take various forms. In sandstones, for example, they consist of small interconnected pores between the grains of sand. In granites, which are made up of interlocking crystals, there may be fissures or fractures, which can be interconnected so allowing water to travel through the rock. Below a certain level, the rock voids are all filled with water. This level is called the water table, and the rocks below it are said to be saturated. By using the voids as a pathway, water can flow through the saturated rocks.
The ease with which water flows through rocks varies with the rock types. For example, if the rock contains large well-connected pores or voids, like the sandstone in (a), or extensive linked fractures, like the granite in (b), the water will flow easily through the rock. In (c) there are large pores in the rock, but the pores are not interconnected, so the water cannot flow easily through the rock. Any repository would ideally need to sit above the water table and within a rock that resisted the flow of water.
A depositary in Yucca Mountain a mountain in Nevada US. This site was deemed to be near perfect as regards its geology. Nuclear Power is the best option we have at the moment, all things considered and we should continue to use it. We need to bring down the construction costs but you need consistency of new build to have a competent workforce and the length of time to build nuclear plants and political changes/uncertainty often don’t help. The waste issue is important and it is imperative that we continue to research ways to deal with waste and look to fusion as the plans for the future of power generation,
The main argument of nuclear energy is that it has no carbon emissions and so reduces global warming when used instead of coal. The argument against it is the toxic waste products and the environmental damage they can cause. Investing in nuclear power as opposed to renewable energy sucks all the funding away from producing cleaner energy that is without toxic waste. Nuclear fusion is an exciting idea i wrote an article year ago.  I think nuclear power produce will be  continued. The waste is a concern and we power plants should are been  built for energy and old power plants those not capable of safely producing to meet the energy requirement remain hazard issue. .
Efforts were made to treat the water and remove some of the radioactive isotopes within it using the filtering system mentioned in the news report you heard in the previous step. This has had some success. The long-term aim is to be able to safely release the water to the sea with a legal discharge concentration of activity. The presence of radioactive isotope of Hydrogen-3 (tritium) is limiting how much water can be returned.
At the power plants, after the incidents I raised in my other articles.  Its unsafe for Human to access for clearing up and robots are made for the job. The problem is likely to continue as long as the source of the radioactivity is still present. There are however severe problems connected with the removal and containment of melted fuel and debris. The radiation is still so high that workers cannot safely be within reactors 1 to 3 for even short amounts of time so technological advances would be required to begin dismantling in the near future. Two robots entered the reactors in April 2015 and stalled possibly due to high levels radiation. As of 2016 the clean up has barely begun with Tepco revising its date for fuel removal from 2021 to 2025.
In all likelihood, it will take 30 to 40 years for all the cores to be dismantled and removed off site and the flow of water may well remain a difficult issue until then.  Fatema Miah, Solihull, uk. fatemamiah@mail.com