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Uranium contamination in Bathinda’s groundwater Trends Prof Yash
Pal THIS UNIVERSE |
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Uranium contamination in Bathinda’s groundwater A ‘high’ concentration of uranium has been detected in the groundwater of the Bathinda area. This presence of uranium makes the avilability of clean drinking water to village residents extremely difficult. It is known that even with the mode of RO system being deployed for making available clean drinking water, it is not possible to screen out these radioelement pollutants even though people are ready to pay the cost of 10 paise per litre of RO treated water. Cancer prevalence is reported in certain pockets such as Jajjal village of Talwandi Sabo block. There were 107 confirmed cases of cancer patients from this area, out of which 80 were female. Jajjal village witnesses four to five cancer deaths every year. It has been reported that the village pond is filled with filthy water which, if consumed by cattle, leads to sickness. The village used to be supplied with filtered canal water, but that source has become contaminated. Recent samples tested by the PPCB were found to be contaminated with DDT and Benzene Hexachloride in addition to other toxic substances thus rendering it unfit for drinking even after filtration. Now it proposed to make RO water available to Jajjal village whose ground water has been found to contain uranium concentration of 59.3 mg per litre. Will we be able to assure ‘clean’ drinking water to the village population, is a question difficult to answer, when the groundwater carries a heavy dose of heavy metals like arsenic selenium, mercury, chromium and now radioelements like uranium. A team of experts has carried out investigations on this issue and tested 90 samples of groundwater taken from tubewells and hand pumps from 22 villages of Bathinda district. These samples were tested jointly with experts from BARC and Kota Research Centre of the Kota Atomic Research Station. For testing two modes were used — Fission Track mode and Laser Flourimeter technique. This dual mode was adopted to be doubly sure of the results obtained. Various authorities on the subject widely differ on the matter and a consensus on the maximum permissible uranium concentration in drinking water is yet to be arrived at. The maximum acceptable concentration in drinking water is guided by its chemical toxicity. Even if we adopt the ‘liberal’ WHO limit of 15 mg/litre, more than 77 per cent of samples have failed and groundwter of 17 villages tested remains unfit for human consumption. When water containing radioelements like uranium is consumed, some part is retained in the body while the rest is excreted. The retained portion appears to get ‘concentrated’ in the hair and this retained uranium has an adverse impact on humans and livestock. The question that needs probing is how uranium has contaminated Bathinda district’s groundwater. Experts at GNDU say the uranium could have come from the Tosam Hills of Bhiwani area of Haryana, where granite rocks having high radioactivity are found. The concentration of uranium in groundwater of that area is about 60 mg/litre. But it is difficult to understand how this contamination occurred in the absence of any major geological shift.The likely possibility is that it may be on account of environmental changes caused by wastes produced by the Thermal Plants of 1360 MW operating in Bathinda district since the 1970’s. These power plants burn 24,000 tons of coal daily to produce electricity, and produce flue gases, flyash and pond ash which is stored in Ash Ponds in the form of slurry (Ten parts water to one part ash). The Ash Ponds have not been provided with “Lining Material” so as to prevent seeping water to mix with the groundwater and cause contamination. An examination of samples from close to the Ash Pond at Buchu Mandi near the Lehra Mohabat Thermal Plant, and Jai Singh Wala near Bathinda Thermal Plant reveal that in the case of the former the concentration of uranium is 74.9 mg/litre with the average value of 56.9 mg/litre (highest value tested of 90 samples taken), while in the latter case the values obtained are 61.1 mg/litre with the average value of 52.7 mg/litre. So the “epicentre” of the activity lies near the thermal plant which has resulted in contamination of groundwater of the area. As we move away from the epicentre, the concentration of uranium in the groundwater decreases. At the farthest sample tested, i.e. of Rampura, the concentration measured is of 9.3 mg/litre, the lowest value tested. Coal contains low levels of uranium, thorium and other ‘naturally occurring radioactive materials’ (NORMs) whose release into the environment leads to radio-active contamination. While these NORMs are present only as trace impurities in the coal, these tend to get concentrated in the residues once the coal is burnt in thermal plants. A significant amount of these NORMs get released into the environment through the flue gases, fly-ash and the furnace bottom ash which keep accumulating in the ash-ponds from where they tend to leach into the groundwater sources. An earlier radio-elemental study of the Kolaghat Thermal Plant in West Bengal shows how the presence of uranium in coal has affected the environment around the thermal plant, including the groundwater. The analysis of other thermal plants of West Bengal, such as Durgapur and Bandel are also available and show similar findings. Close testing needs to be carried out by the PPCB and BARC to find out whether ash ponds are the source of contamination and, if so, what measures need be taken to rectify the position and make available “clean water” for human consumption. Also, coal needs to be analysed to determine the concentration of NORMs so as to select the ‘cleanest available’ and to minimise the quantity of these radioelements getting released in the air and seeping into the groundwater from the ash-ponds. With several Ultra Mega Thermal Plants for Punjab in the pipeline, this issue is of utmost importance. Additionally, the possibility of extracting precious uranium for the thermal plant ash ponds not only in Punjab but from all over India needs to be considered seriously. |
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Trends
Washington: Scientists have discovered a gene which they claim is linked to misery. An international team, led by the Western Australian Centre for Health and Aging, has in fact identified the genetic variation in C-reactive protein gene that actually predisposes individuals to developing depressive symptoms. Prof Osvaldo Almeida, who led the team, said: “What we found in this particular piece of research was that the genetic variation in the CRP gene dampens the CRP response. “In other words, it decreases your ability to fight off stressful events efficiently and this is associated with depressive symptoms. The link between CRP and depression gets more prominent the sicker the person gets.”
Fish ‘have human ability to learn’ London: Fish are more clever than you thought, for a new study has found that although worlds apart, the way they learn could be closer to humans’ way of thinking. Researchers have found a common species of fish which is found across Europe, called nine-spined stickleback, to be the first animal to exhibit an important human social learning strategy. The sticklebacks can compare the behaviour of other sticklebacks with their own experience and make choices that lead to better food supplies, found the study published in the ‘Behavioral Ecology’ journal.
— PTI |
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THIS UNIVERSE I am a class 10 student. I have heard that the mass of bodies changes when they move at the speed of light. How is this possible? A simple way of understanding this might be the following: Einstein says that velocity of any object cannot exceed the velocity of light c. But we cannot allow Einstein to also limit the energy and momentum of a particle to an arbitrary maximum. For example the momentum must be mass multiplied be velocity. Therefore close to the velocity of light the only way momentum can increase is by increasing the dynamic mass of the particle. We, therefore, work out a formula for the dynamic mass of particle as function of velocity that satisfies the relation between momentum and energy. Remember, we do not, indeed cannot, change the value of the intrinsic mass, called the rest mass of the particle. The requisite formula for doing this is called the Lorentz transformation. It through these considerations the Einstein arrived at the famous formula E=mc2.. Therefore keep reminding your self that when we say that the mass of a particle increases with it energy in the certain way, we are thinking only of the dynamics of the particle – the relation between it energy and momentum. Energy equivalent of its rest energy always remains mc2, in the rest frame of the particle. According to Newton’s third law of motion, every action has an equal and opposite reaction. Yet, we are still able to move objects on surfaces having friction. If this law holds true, then no object should move as the friction should apply the same force as we apply on the object. Hence no net unbalanced force would be there on the object due to which it would not accelerate. Yet the objects move. What is the reason behind
this? On a rough surface there are little hills and valleys that obstruct the motion of what you are trying to move. Sometimes these hills are tough. On other occasions not so and they break up easily and allow you to move forward, though rather slowly because of the energy lost in breaking up those hills. I do not see any violation of laws. Can pressure be negative? If yes, please illustrate? The term negative pressure is often used in relative terms. Or in reverse, we can talk of positive pressure. If you do not want contaminated air from outside to not soak inside a clean room you can keep the inside pressure positive with respect to the outside. In many air condition stores, where the entrance door is kept open, the pressure inside is kept higher to ensure that hot air from outside does not keep rushing in. In both chemistry and physics experiments, the air from vessels containing water can be sucked out to make it boil at a lower temperature. In meteorology one talks of low pressure zones as areas to which wind from all sides would converge to cause rain and some times even cyclones. Readers wanting to ask Prof Yash Pal a question can e-mail him at [email protected] |
