May 02, 2010

Prabir Purkayastha

THE near fatal radiation exposure in the Mayapuri scrap has led to hospitalisation of 11 people. The cause has now been identified as radioactive cobalt 60 sources that were mixed up in the scrap. What neither the Atomic Energy Commission nor the government has disclosed is that it is not the first time that we have found radioactive cobalt 60 in metal scrap. Almost two years back, Germany reported finding radioactive steel coming from India. The French followed with reports of radioactive buttons in elevators originating from radioactive steel, again from India. It is amazing that even after this and known dangers to the people who would be inadvertently exposed to high radiation, the government of India and its agencies took no steps regarding the prevention of such incidents. Neither do we have any clarity on how such incidents have occurred or from where the offending radioactive material originated.

The Atomic Energy Commission, the keeper of the nation's nuclear safety has virtually washed its hands off the affair, claiming that the radiation material appears to have originated from imported scrap and AEC had no responsibility regarding this. This is what Prithviraj Chavan has also echoed in the parliament. What this shows is the utter callousness with which the government authorities conduct their nuclear affairs. To add gratuitous insult to radiation injury, Prithviraj Chavan tried to relate it to the Nuclear Liability Bill pending in the parliament – apparently this bill has provisions relating to radiation damage from scrap. The truth is that the Nuclear Liability Bill covers only nuclear reactors, and the last we know, there are none in Mayapuri!

Now it transpires that the radioactive material originated from the Delhi University Chemistry Department, which had disposed of as scrap a gamma radiation equipment with an active source of cobalt 60. Therefore, this falls squarely within Atomic Energy Regulatory Board (AERB) /AEC's jurisdiction, as they are supposed to track all radioactive sources in the country.

The story of radioactive scrap is not new. In August 2008, a container from India containing bars of steel to be sent forward to Russia, was detected by port authorities in Hamburg to have very high radioactivity levels. In one day, the radioactivity level was equal to what is a safe dosage for a year. Neither was this an isolated incident. According the Spiegel Online International (Finds of Radioactive Steel on the Rise in Germany, Christian Schwägerl, 02/16/2009), “For months, similar cases have been found across Germany, all involving bits of metal contaminated with radioactive cobalt. And most of them come from the same source: three steelworks in India, in particular a company called Vipras Casting, based in Mumbai”. Later reports indicated that apart from Vipras Casting, there were another five companies involved. They were Bunts, Laxmi Steels, SMK Steels, Pradeep Metals, Goradia Special Steels Ltd.

The Atomic Energy Commission and the Atomic Energy Regulatory Board (AERB) has total responsibility in the country for all such matters.  Satya Pal Agarwal, head of the radiological safety division of India’s Atomic Energy Regulatory Board stated at that time that AERB was tracking the whole supply chain. We have yet to hear what happened after the supply chain was “tracked”. Instead, we hear exactly similar sounding statements emanating from AERB. The only grudging additional information given is that scanners are supposed to be installed in all the ports, which are lagging behind. No details of what are the steps that AEC or AERB took after the last round of radioactive contamination was reported.

The issue is clear. Radioactive material is mixed up in scrap – either imported or local -- and finding its way into steel making. Obviously, iron and steel scrap is used extensively in India and elsewhere for making steel. This steel is not only exported but also finds its way into domestically manufactured engineering goods. This is the danger – such “hot” steel is circulating in India already and the government is taking no steps regarding such danger to its people. If more than 150 tonnes of steel have been reported to have such radioactive contamination, how much is circulating here? It would be foolish to think that only exported steel has been contaminated and not domestic manufacture.

LESS IMPORTANCE FOR PEOPLE’S LIVES

In today's day and age, peoples lives are assumed to have less importance than the value of our exports. Obviously, if the steel used in engineering industry gets contaminated, this poses a huge risk for our 23 billion dollar exports in this sector. If not for the health of its people, at least for protecting its industry and its exports, we would have expected the Indian government to carry out an aggressive program with respect to import of suspect iron and steel scrap. Yet, after almost two years, we find that the scanners and radiation measuring instruments to monitor imported scrap is yet to be functional in our ports. The government has passed the buck to the steel makers telling them that they must check for radioactive contamination of all their inputs.

In a statement to the press, Dr S Banerjee, chairman of the Atomic Energy Commission said , "Whatever happened in Delhi had nothing to do with the activities of my department. The scrap materials come from other countries and it was not possible for the Department of Atomic Energy to check at the entry points if there were any radioactive materials in them. Checking all the containers laden with scrap was not possible. Instead, scanning could be done. While a decision to install scanners had been taken, implementation was taking time." This statement makes clear – according to AEC – they are not responsible for radioactive material if it is mixed up in imported scrap. According to Dr A Goplakrishnan, former chairman, AERB, AEC chairman's position is not in conformity with the constitutional responsibilities that AEC and its subordinate institutions have. Under the country's law – the Atomic Energy Act of 1962, it is their responsibility and this is an attempt by AEC and AERB to evade their legal responsibilities. If we take into account that AEC and AERB have been fully aware of the risk of imported radioactive scrap, their evasion of responsibilities becomes even more glaring.

As Dr Gopalkrishnan points out (http://news.rediff.com/column/2010/apr/22/delhi-radiation-case-aec-aerb-also-culpable.htm), the Act's sections 16 and 17 makes clear that monitoring all such possible radioactive substances is a part of AEC's duties. Subsequently, Atomic Energy Regulatory Board was set up in 1983 and this part of the mandate was transferred to AERB. Dr Gopalkrishnan points out, “One of the responsibilities legally assigned to the AERB through its founding notification is to review operational experience in the light of the radiological safety criteria recommended by the International Commission on Radiological Protection (ICRP), International Atomic Energy Agency (IAEA) and other similar international bodies, adapt them to suit Indian conditions, and thereby evolve major safety policies.

This aspect is especially relevant in dealing with issues of missing and misplaced powerful radioactive sources, a subject in which IAEA has enormous experience and data bases. IAEA has also, over the years, developed procedures for preventive and corrective action, in consultation with various countries. After evolving appropriate national policies based on this world experience, the AERB is to implement them and maintain a high degree of nuclear safety and security in the country”.

The AEC Chairman cannot wish away the statutory obligations that the Act imposed on AEC. In fact, the radioactive steel cases in Europe were all dealt with their respective nuclear agencies who also put in place the measures to prevent such occurrences as well as the safe disposal of the radioactive steel. Contrast this with India, where the steel company was told to bury the 21 tonnes of radioactive steel in its premises. The company also complained that AERB was not very cooperative on this question. (http://www.timesnow.tv/India-dumping-ground-for-radioactive-waste/articleshow/4333103.cms).

One of the advantage of radioactive contamination for post mortem purposes is that it does leave a physical trace. The people are entitled to ask what happened last time when AEC/AERB traced the path of radioactive scrap going into steel plants? Is it the same source that caused the problem last time that is responsible now also for the Mayapuri incident or is it a new source? Where did the scrap originate last time and what are the steps that AEC/AERB took then? None of these questions have been answered and given AEC/AERB's record of opaque functioning and stonewalling all questions of safety, none may materialise.

INDIA BECOMING A HAZARDOUS DUMPING GROUND

India is already offering itself as a hazardous dumping centre to the world. Ship-breaking in Alang has come under the repeated scanner of environmental groups. It now seems with its lackadaisical attitude to radioactive waste and failure to install scanners even after two years of such known cases of dumping, we are signalling a window of opportunity for unscrupulous nuclear waste disposal companies abroad. Come and dump your radioactive cobalt here, we will take some more time before we can even monitor such shipments.

The Delhi University case also shows that AERB needs to strengthen its monitoring and tracking of all radioactive sources. Sadly, the response from AERB and AEC does not show and increased awareness of this. This is what we need to rectify to avoid more such incidents.

April 25, 2010

Prabir Purakayastha

THERE are three important events that have taken place recently on the nuclear issue. One of this is the restarting of the stalled START process of cutting down of nuclear weapons by the US and Russia. The second is the Nuclear Posture Review just concluded by the Obama Administration. The last is the Nuclear Materials “Summit” that the US held with 46 countries.  None of them provide any basis for thinking that the US has changed its positions in any fundamental sense – it goals still remain nuclear dominance of the world and isolating Iran (and North Korea). By themselves, they do not constitute a radical departure from past policies. However, given the bleak global nuclear disarmament landscape today, Obama's few gestures may indeed spark some hope for brining nuclear disarmament on the table once again.

Iran was not called to the Nuclear Material Summit called in Washington. It has responded by holding a global conference and calling for universal nuclear disarmament. Ayatollah Khomeini has followed this with a characterisation of nuclear weapons as haram and therefore not a legitimate weapon even in a war.

All this would provide a backdrop to the Nuclear Non-Proliferation Treaty Review Conference (NPT Revcon), which is to take place in May this year in New York. In 2005 NPT Revcon, the US was not willing to put any disarmament measure on the table while asking that the non-nuclear weapon states should give up their right under Article IV of NPT for the fuel cycle. This time also, the US agenda on the fuel cycle with its obvious target of Iran is unlikely to change. Whether the new START measures, which still retain thousands of warheads in US and Russian hands qualify as good-faith negotiations towards nuclear disarmament as mandated under Article VI of NPT remains to be seen. It will be presented as such even though it leaves sufficient nuclear weapons in US and Russian hands to blow up the whole world many times over.

What are the limits proposed in the new START (the old one expired in 2009) signed this month in Prague and what are the reductions? There are essentially three central limits under the current START program. They are:

Total number of launch vehicles is limited to 800 -- a reduction of about 10 per cent of US (Russians have less functional launchers in any case) launchers. The launch vehicles are ICBM’s, submarine launchers and nuclear weapon capable heavy bombers, with all such bombers being treated as one for the purpose of this count.

Total number of deployed launchers to 700

Total number of deployed warheads to 1,550 --  a reduction of about 30 per cent from 2,200 each

By any reckoning this is a very modest reduction, given that the next biggest nuclear weapons state, China has an arsenal of about 400 nuclear weapons. Even worse, START talks only of deployed warheads and weapon launch vehicles and not about the huge stockpile of actual warheads – in storage or un-deployed -- of about 10,000 warheads each. Unless the US and Russia are willing to reduce this stockpile, the so-called reduction contributes to atmospherics but little else.

The US insisted that the missile shields would not be  a part of the START process. That means that the US can now go ahead with their missile shield and ring Russia using it. This shield has been the bone of contention between the US and Russia, as all arms control discussions accepts the link between offensive and defensive capabilities. One of the first arms control treaty was about Anti-ballistic missile – the ABM Treaty. This is what the US has formally jettisoned. The current START version accepts this link between offensive and defensive capabilities, but in a non-binding and quite vague preamble. So the US can go ahead install a missile shield in Eastern Europe, ostensibly targeted against Iran.

NPR 2010: NO PATH BREAKING REVIEW

The Nuclear Posture Review 2010 (NPR 2010) has been hailed by the US media as path breaking. A closer perusal makes clear that it is nothing of the kind. It accepts – for the first time after the break-up of the Soviet Union – that Russia is unlikely to attack the US! So the NPR 2010 acknowledges that the threat is no longer from other nuclear states but non-state actors. Even then, it does not give a no-first use pledge against either nuclear or non-nuclear states. The second key point in the review is that it states it will not use nuclear weapons against non-nuclear weapon states who are in compliance with NPT. However, who is in compliance with NPT or not, is a decision that the US will take on its own: the US can use nuclear weapons against any country by simply declaring it in non-compliance with NPT. It has already said that North Korea and Iran are in non-compliance so “eligible” for use of nuclear weapons. Even Syria has been held to be in non-compliance – for reasons that the US Administration is not willing to divulge.

Even this limited restriction of the use of nuclear weapons might be considered to be a step forward. But this is not the only loophole for the US to use nuclear weapons. On biological weapons, it has also hedged its bets. The clause reads, “Given the catastrophic potential of biological weapons and the rapid pace of bio-technology development, the United States reserves the right to make any adjustment in the assurance that may be warranted by the evolution and proliferation of the biological weapons threat.” Shorn of verbiage, it means that the US can use nuclear weapons against a biological weapon attack.

On non-state actors, the NPR 2010 allows the use of nuclear weapons against non-state actors who are seeking WMD's. This indeed nullifies all talk about not attacking countries with nuclear weapons. Non-state actors, by definition, reside in states which they do not control. What the US is saying is that it can attack any state which it feels harbours non-state actors who, in the US opinion, may acquire WMD's. Cutting to the chase – the US has provided itself a loophole in its strategic doctrine to use nuclear weapons anywhere in the world.

The other key question is that the US always held that it does not need to wait for an attack: it can pre emptively strike any country which has weapons of mass destruction – nuclear, biological or chemical. Apart from the chemical part, it is difficult to read into the Obama doctrine a fundamental shift away from this position. A change yes, a major change no.

The Obama administration would like to project itself as a mover on nuclear disarmament. Therefore the atmospherics without changing any fundamentals premise of the US nuclear policy.

This policy was most evident on the so-called Summit called by the US and attended by 46 countries. The list of countries drawn up seemed to have been with an eye on which countries the US needed to lobby with for its proposals on further and much harsher sanctions on Iran. This was the diplomacy that the US carried out on the sidelines, while ostensibly focussing on the safety of the fissile material and stopping future production of fissile material. One of the biggest threat to the world comes from the huge stockpile of 10,000 weapons each that Russia and the US have. Why talk about protecting it, when we need to dismantle this, which has – even by the gargantuan appetite of the US and Russian armed forces – no earthly strategic value?

FUNDAMENTAL REVISION OF NPT ARTICLE IV

All this is careful build-up to the NPT Revcon. What the US is trying is a fundamental revision of the NPT Article IV, which allows any country which abjures nuclear weapons to still have the fuel cycle.  This allows countries to generate “break-out capability”, the way that North Korea did. This change on nuclear fuel is not credible if the other part of the Treaty – calling for nuclear disarmament – is not seen to make progress. The US thrust is to make enough noise about disarmament, while pursuing the goal of controlling the fuel cycle. The problem for the US, as also other nuclear weapon states, is that it is becoming easier and easier to develop nuclear weapons capability. Unless the world abolishes nuclear weapons, global nuclear security is not achievable. And it is the nuclear weapons states that need to take the first steps. Unfortunately, Obama's steps do not qualify as a serious disarmament initiative. Its only importance will be, if it brings nuclear disarmament back on the world's agenda.

14th April, 2010

D. Raghunandan


Earlier articles in these columns have shown how the odd careless remark, a few errors in judgment, a lapse in scientific rigour and peer review procedures, as happened over the clearly erroneous prediction that Himalayan glaciers would melt by 2035, are pounced upon by climate skeptics and corporate lobbies to undermine the scientific understanding of societally induced climate change and hence undercut efforts to bring about policy changes to avert the impending crisis. This despite massive and mounting amounts of evidence to show that, if anything, the problem is even more serious than the extant scientific consensus says it is. For instance, many recent studies on polar ice have tended to show that ice cover at both poles is shrinking faster, and that consequently sea levels would rise even more, and more quickly, than previously thought.

Diminishing ice cover is often referred to as clear evidence of global warming. Further, since the large quantity of terrestrial ice is known to play an important role not only with regard to sea level but also to regulating global and regional climate, changes in ice cover are closely watched and carefully studied.  For many years, satellites have been mapping the area covered by ice and this data has formed the basis of much prediction on the extent and impact of global warming. For instance, the Fourth (and latest) Assessment Report of the IPCC (IPCC/AR4) in 2007 noted that “satellite data since 1978 show that annual average Arctic sea-ice extent has shrunk by 2.7% per decade” and based on that projected a rise in sea levels  by 28-43 cm (centimetres) by 2100. But a subsequent authoritative report titled Antarctic Climate Change and the Environment released in 2009 by the highly regarded Scientific Committee on Antarctic Research projected a significantly higher sea-level rise of 1.4 metres by the next century!

Reduction in polar ice cover is most dramatically seen in the Arctic and especially around Greenland. Since 2000, the area of the Arctic Ocean covered by ice in the summer has reduced drastically, with September 2007 recording the minimum and 2008 and 2009 being similar. (see satellite images below)

There is thus little doubt that ice cover is shrinking. The real question is how much? So far we have been talking only about the area covered by ice, not about the total volume or quantity of ice. To get from area to volume, one needs to measure the thickness of the ice. The Cryosat-2 satellite (so named because it seeks to study the cryosphere or parts of the earth covered by ice) was launched by the European Space Agency (ESA) on April 8 last week to do precisely this at a total mission cost of $180 million (Rs.870 crores).

Problem and Challenge Much of the solar radiation reaching the earth’s surface is reflected back to the atmosphere and to outer space. Permanent ice sheets, especially when covered by snow, have high ‘albedo’ (literally whiteness or more accurately reflectivity) and reflect around 80 percent of sunlight. This helps the ice to stay frozen and plays an important role in maintaining the heat balance of our planet. However, when ice cover begins to melt, the albedo effect gets diminished, thus reducing the proportion of solar radiation reflected back and hence increased absorption of heat by the ice, leading in turn to what is termed ‘positive feedback’ that is, increased ice melt and greater warming of the earth. Under normal seasonal variation, vast amounts of ice melt every summer and freeze again in the winter but, with global warming, melt rates are getting higher while the re-freezing is slowing down.

Polar ice is of two types, ice that covers land (ice-caps, defined as less than 50,000 sq.km in area, or ice-sheets, larger than that, although the former term is commonly used to describe both) and sea ice (formed by freezing sea water). These two forms of ice behave differently, have differing impact on climate and will affect the planet in diverse ways as they melt due to global warming and pose distinctive challenges for measuring their thickness.
Seasonal changes of sea ice are known to have a significant influence on ocean circulation patterns called “thermohaline circulation”. When ice melts, fresh water enters into the surrounding ocean reducing its salinity and therefore its density. In reverse, as seawater cools and sea ice forms, the salinity and density increases, causing the surface waters to sink down. Continuous such action drives deep ocean currents towards the equator and away from the polar regions, in response to which a return flow of warmer and less dense water is drawn towards the poles from higher latitudes towards the equator. These ocean currents have a profound influence on climate and weather. One of the more important such warm water currents is the Gulf Stream from the Gulf of Mexico towards the Arctic which keeps Britain several degrees warmer than other northern European countries. With climate change and rise in average temperatures globally, and volumes of sea-ice declining, the Gulf Stream would become significantly weaker, leading to much colder conditions in regions on both sides of the northern Atlantic (thus showing that “global warming” can be a misleading term!). There are even apprehensions that at some particular point, the mechanism governing these important ocean currents could get “switched off” leading to catastrophe, the subject of a recent Hollywood movie!

It must be remembered, though, that melting of sea-ice has no impact on sea levels since the ice is already floating in water.
Unlike sea ice which is only a few metres thick, ice caps or ice sheets over land, such as those that blanket Antarctica or Greenland, are several kilometers thick. Till recently it was thought that ice caps were relatively stable, certainly in their interiors, but evidence now appears to have dashed this fond hope. Ice caps both in Antarctica and in Greenland are now known to be melting, especially from their base, due to the effect of warming oceans. When this huge quantity of ice melts, the water released into the oceans will undoubtedly contribute significantly to a rise in sea levels.
However, to better understand and make predictions about these and related phenomena, scientists need to know much more about the total volume of ice which in turn needs measurement of its thickness.  

Sea ice being thin, its thickness can be measured directly, such as by drilling into it from above, but this method can only provide localized information over a small area. Thickness of ice caps, on the other hand, needs to be estimated by measuring the height of its surface relative to the land below, not an easy task by any means.     

Cryosat-2 ESA’s     Cryosat-2 is the second attempt at undertaking this task, the first mission in October 2005 having failed right at launch due to a software problem affecting the rocket. This time, ESA used Russia’s Dnepr launcher from the usual Soviet-era Baikonur station in Kazakhstan. The launcher was shot off the pad by a high-explosive charge with, unusually, its upper stage flying backwards pulling the satellite up rather than pushing it from below, the new configuration expected to enable greater accuracy in injecting the satellite into its designated orbit.

The spacecraft orbit is the steepest hitherto, taking it as close to the poles as possible. NASA’s ICEsat, with a laser altimeter, flew in a high inclination orbit of 86 degrees but Cryosat2 goes even better with an orbital path of 88 degrees north and south on each orbit, covering most of the Arctic and Greenland coastline of which only 10 percent is covered by current satellites. This clearly non sun-synchronous orbit requires that the spacecraft’s solar panels are tilted so that it can receive maximum possible sunlight and also that it carries newly-designed high capacity batteries.

The satellite (see image below) carries as its primary payload an advanced SAR- Interferometric Radar Altimeter (SIRAL). SAR stands for Synthetic Aperture Radar which provides high-resolution and simulated 3-D images even with small antennae by creating a rapid sequence of images while in motion which are then computationally put together. (See PD, May 3, 2009 for a more detailed explanation). To complement the altimeter, the payload includes a radio receiver called DORIS (Doppler Orbit and Radio Positioning Integration by Satellite) and a laser retro-reflector. The International Laser Ranging Service or ILRS, a global network of laser ranging stations, will support the mission. To provide the datum or reference position of the satellite itself against which all other positional readings are read to obtain absolute data, the satellite relies on the oldest navigational method, namely the position of stars which it continuously monitors through three star-trackers. 

The spacecraft’s instrumentation provide accurate data on sea-ice ‘freeboard’ or height of floating ice above sea level, and on the elevation of ice sheets. The SAR technique enables high resolution data in the direction of movement of the satellite. In conventional radar altimeters, distance to the top of the ice would be measured by the radar echo off the nearest point on the surface, but on sloping surfaces such as on land and on the edges of ice caps, there is no reference point to indicate where on the slope this nearest point is. The SAR’s series of multiple images taken at 10 times quicker intervals than conventional radars enables determination of the position and height of the surface in the along-track direction while left and right echo positions are provided by the SAR-interferometry mode which provides the angle of the returning echo, thus all together giving a three dimensional picture and accurate measurement of the thickness of the ice.

September 1980

As with all remote sensing, error correction and calibration has to be done through comparison with ground data both before and after launch. Arctic and Antarctic expeditions are already measuring snow density and behaviour relative to the ice below. After the launch, ground-truthing will be done to validate the radar data obtained and enable more accurate interpretation of the satellite data through the rest of the mission expected to last 3 years.

The Mission goal is to measure changes in ice thickness within 10% of the expected inter-annual variation which works out to a required accuracy of about 7mm per year averaging out variations between sea-ice and ice sheets. Data obtained so far shows that this goal will be met quite comfortably. Cryosat-2 will undoubtedly yield invaluable data on polar ice and considerably advance scientific knowledge of climate change and its impact, and also put at rest much speculative debate and scepticism.

September 2007

An interesting sidelight is that the launcher that put Cryosat-2 into orbit is a modified Soviet-era SS-II ballistic missile only slightly modified for commercial use. And earlier in the week, NASA also launched a modified Global Hawk, the US Air Force’s most potent Unmanned Aerial Vehicle (UAV) spycraft that can fly at high altitudes of over 60,000 feet for a very long time, to monitor sea-ice and ice sheets. If countries so decide, all knowledge and technology can indeed be harnessed for the collective benefit of humankind.  Talk about turning swords into ploughshares.