Chashma - Almost too Late

On 23 November, the process began of loading the 36 tons of radioactive uranium fuel into the Chashma nuclear power plant. At the same time, it was announced that the reactor will start producing power by the end of March, 2000. In the eight years that it has taken for the project to get to this stage, there has never been a serious, well informed public debate about the safety and possible health and environmental effects of the Chashma reactor, despite everything that is known about the enormous destruction that follows a severe nuclear reactor accident. It may soon be too late to start this debate.

There are numerous reasons to be concerned about the safety of Chashma. The first is the location of the reactor. The site, close to Chashma Barrage on the Indus River, about 30 km south of the city of Mianwali, has been a problem from the very beginning. Among the early critics was I. H. Usmani, who served as Chairman of the Pakistan Atomic Energy Commission from 1960-1972. In a 1981 interview, Usmani publicly expressed his concern not only about the risk of earthquakes close to the site, but also about the fact that the reactor sits on the banks of the Indus River - which irrigates a large fraction of the country south of that point. Usmani's criticisms prompted a written request from President Zia-ul Haq not to continue public discussion of such topics.

The Chashma reactor is sited in an area that independent studies have shown to be an active earthquake zone. International records of earthquake activity show that between 1973 and 1999 there were 24 earthquakes recorded as having an epicenter (the point on the Earth's surface directly above the source of the earthquake) within 100 km or so of the reactor site, and five earthquakes that took place within 40 km of the site.

These records are for large earthquakes that can be reliably detected at great distances. There are many smaller earthquakes that can only be observed close to where they take place. Sometimes, these small earthquakes are a sign that a large earthquake may be possible in that area. The limited public data that exists about earthquakes close to Chashma is very troubling.

In the mid-1970s, the Pakistan Atomic Energy Commission asked one of the world's leading centres for earthquake research, the Lamont-Doherty Geological Observatory of Columbia University, to study and prepare a series of reports on the seismic hazards of the Chashma nuclear power plant site. This involved putting sensitive seismometers around the site and recording all the earthquake activity. In a six month period, there were 19 earthquakes located within about 50 km of the Chashma site, the nearest was at a distance of less than 5 km.

Even more disturbing than the record of past earthquake activity is the possibility of a very large earthquake close to Chashma at some time during the life of the reactor (planned for 40 years). The Lamont-Doherty study discovered a set of active earthquake faults near the site and noted that one of these faults may be "located very near the site, possibly directly below" and was potentially capable of generating a very large earthquake, possibly one of magnitude 7.0 or larger. Not surprisingly, the Lamont-Doherty study concluded that "the seismic risk at the Chashma site is quite severe".

The Pakistan Atomic Energy Commission seems to have ignored the Lamont-Doherty report, despite having asked for it. At the same time, the Commission has not released details of any of its own geological and geophysical surveys of the area around Chashma, nor explained why it believes the earthquake risk at the site is less than had been suggested. They have simply gone ahead and built the reactor.

The earthquake risk to the Chashma reactor is made potentially more severe by its position on the banks of the Indus River. The ground there is silt and sand, deposited by the flooding of the river over countless years, and water is so close to the surface that the ground may be almost saturated. These characteristics make the area susceptible to 'liquefaction'; a phenomenon where, in response to an earthquake, the ground loses all its strength and flows as if it had suddenly become a liquid.

It does not take very strong earthquakes to generate liquefaction, but where it has happened the consequences can be devastating. In an earthquake in 1964, in Alaska, liquefaction led to almost 3 km of a coastal area sliding 300m. If there is a gentle slope, the "liquefied" soil can flow downhill, causing severe damage to the foundations of buildings and breaking pipelines. On flat ground, liquefaction can cause rigid structures to buckle and break, buildings to sink and tip over. These effects significantly increase the risk of an accident. PAEC has not shown how it has incorporated concerns about earthquake risk and liquefaction into the design of Chashma.

The second major area of concern is the safety of the Chashma reactor design. Originally designed by the China National Nuclear Corporation as a replica of China's first indigenous reactor, Qinshan-1, the Pakistan Atomic Energy Commission claims it has had to "enforce numerous design changes". It is to be hoped that these changes were to increase the safety and efficiency of the reactor. While PAEC may see the design changes it made in Chashma as evidence of the skills of PAEC scientists and engineers, the need for the changes suggests that the original Chinese design had "numerous" problems that had to be put right or features that needed improvement. The initial Chinese design has not been made public, nor the changes that PAEC enforced.

PAEC is not alone in having suggested changes in the Chashma design. In September 1993, a team from the International Atomic Energy Agency (IAEA) reviewed the Chashma design and, according to PAEC, "made several recommendations for further improvements". This means that PAEC's earlier evaluation had missed "several" problems in the Chashma design.

PAEC has referred to this IAEA team and its recommendations as if it shows that Chashma is now safe. But, at the same time, PAEC reports that only "most" of the changes recommended by the IAEA have been made. There has been no explanation of why only "most" and not all of the changes recommended by the IAEA team were incorporated into the reactor. There is also no description of which changes were made and which not made, nor information on who made these decisions and on what basis.

Even if all the design changes proposed by the IAEA team have been made it would not mean the reactor was now safe. The IAEA is not infallible. Like PAEC, it may have missed problems with the design of Chashma. After all, the US nuclear industry and nuclear safety regulators missed the problems that led to the Three Mile Island nuclear reactor accident in 1979, and the Soviet Union's nuclear engineers and nuclear safety inspectors failed to foresee the events that led to the Chernobyl nuclear accident in 1986. The IAEA was not any better. In 1983, the official IAEA Bulletin carried an article claiming that at Soviet reactors, like Chernobyl, a serious accident "is practically impossible".

The interventions of PAEC and the IAEA and the changes they made in the Chashma design point to serious limitations in the Chinese capability to design nuclear power reactors. If the Chinese were well experienced in reactor design and relied on what is accepted as the best international standards there would have been no basis on which to suggest improvements. The only experience that China has in designing and operating a reactor like the one at Chashma was their own Qinshan-1 reactor.

Just how limited is this experience became clear with the accident at the Qinshan-1 reactor in July 1998. The accident was the result of vibrations generated by the high pressure cooling water that is pumped through the hot, radioactive, uranium core that is the heart of the reactor. At Qinshan, it seems some components were not designed and manufactured with sufficient strength to withstand these vibrations. As a result these components failed, debris was sent into the core and radioactivity mixed with the cooling water; the reactor had to be shut down for a year for repairs.

The events at Qinshan suggest that the reactor designers failed to understand properly some key features and consequences of the reactor's operation. In particular, the designers seem not to have estimated correctly either the character of the vibrations in the core or the how strong various components had to be if they were to safely withstand these vibrations. After the accident, the Chinese were unable to deal with the problem and asked for Western help. The failed components at Qinshan have since been redesigned by a US based nuclear company. It is reported that the Chinese will make the appropriate modifications at Chashma, although they do not seem to have waited to see whether the repairs at Qinshan will solve the problem.

These events naturally raise a question about the reactor components at Chashma. The components that failed and created the problems at Qinshan were relatively minor, and had been made in China. All the major components at Qinshan were imported into China from established Western and Japanese nuclear companies. In the case of Chashma, all the key components, the reactor pressure vessel, coolant pumps and control system, have been built in China. This is the first time these particular components and systems have been made in China. China's lack of experience with designing such components and quality control during manufacturing them may increase the risk of failures and equipment malfunction at Chashma. To compound matters, these components are being inspected by Chinese inspectors and those from PAEC that have been trained in China as part of the project.

The Pakistan Atomic Energy Commission has responded to these and similar concerns by claiming that the Pakistan Nuclear Regulatory Board has approved the Chashma project. This is not a serious or credible response. The Nuclear Regulatory Board has as its chairman none other than the Chairman of the Atomic Energy Commission. The Secretary of the Nuclear Regulatory Board is also from the Atomic Energy Commission, as is one other of the three full-time members of the Board. The part time members of the Board by and large have no experience of nuclear reactors or nuclear safety issues. If they do, it is only because they served in the Atomic Energy Commission. Even the budget for the Regulatory Board comes from PAEC. This all leaves very little room, if any, for independent and critical oversight.

Any real evaluation of Chashma should start with an environmental impact assessment. By any possible measure, operating a nuclear reactor is an activity that risks potentially catastrophic health and environmental effects. As a consequences of the radiation released by the Chernobyl accident, many thousands and perhaps many tens of thousands of people across the former USSR, Eastern Europe and Western Europe, may develop cancer, large areas of land were and remain contaminated, and the ground water close to reactor may be in danger for the next hundred years or more.

Pakistan's environmental protection legislation is clear. There should have been an environmental impact assessment of the Chashma nuclear power plant before it was approved. None was ever announced or made public. Therefore, at a minimum, before the reactor is allowed to operate there should be a full, public, environmental impact assessment of the project, which should include a study of all the alternatives that could meet the energy production goal of Chashma. It is worth remembering that the electricity Chashma will, at most, be equal to ten per cent of the electricity lost each year by WAPDA because of inefficiency in its transmission and distribution system.

Given the scale of possible dangers, and having spent almost a decade building the Chashma reactor, it is surely worth taking the time to judge matters calmly and thoughtfully before the real risks are run. If after a proper and informed debate the risks from Chashma are judged too great, then the reactor should be abandoned. Certainly money will have been wasted, but such mistakes have been made before. Better money lost than people's lives or the integrity of their environment, which are priceless.