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Bushehr Nuclear Power Plant is not reliable,
both technically and saftywise
An interview with Masoud Azizi, an expert on nuclear and space safty issues*
By: Alborz Pedram, a member of SavePasargad's Environment Group
Pedram: It is said that the Bushehr Nuclear Power Plant is supposed to be able to render a power output of about 1000 Mwe. On the other hand, Iranian government has announved that the country needs 20,000 Mwe. This means that there is a need to construct 20 more nuclear powers plant like that in Bushehr. Do you believe that Iran has the capability of constructing so many nuclear plants?
Azizi: First, allow me to describe the Bushehr Nuclear Power Plant (BNPP) before I go into more detail.
This reactor was initially contracted out to Kraftwerk Union and Siemens of Germany in mid-70’s. This reactor and her sister plant were called Iran-1 and 2. The twin reactors were supposed to be similar to the 1270 Mwe Biblis Pressurized Water Reactor (PWR) plant in Germany. During the revolution in 1979, BNPP (Iran-1) construction was more than 70 % completed. The construction of this plant was interrupted and the intent of the Islamic Republic (IR) was originally to make the building a “Wheat Silo”!! Between 1979 and 1984, many of the BNPP imported material were wasted (sitting in the outdoors unattended) and the almost completed construction was bombed by Iraqis. In 1984, the IR decided to complete the BNPP construction and tried to use the assistance of Argentina, China, Pakistan before their attention was redirected to Russia. In January 1995 Russia and the IR signed a contract under which Russia would provide one VVER-1000 reactor at BNPP. The VVER-1000 would be similar to the Unit-4 of Russian Balakovskaya plant at Balakovo, Saratov. Although the VVER plant output is between 950-1073 Mwe, the BNPP power output is about 900 Mwe due to modifications made to the VVER to fit into the “Biblis” construction. The BNPP containment building was also modified to fit the Russian VVER horizontal steam generator since VVER doesn’t use the western style vertical steam generators. There have been many other modifications in Auxiliary building as well as the Turbine building. The BNPP is currently being loaded with fuel and is undergoing various cold shutdown and later on, low power tests.
There is no doubt that Iran needs more electric power to satisfy the increasing demand. The current fossil power plants as well as other sources of energy production such as hydroelectric, etc. are getting old and are in constant need of maintenance. With increasing population, this demand will also increase. Nuclear energy is definitely a very sound alternative to the fossil power plant as they do not generate as much green house gases and can be a lot more economical. France is producing about than 85% of their electric power from the nuclear power plants. However, while nuclear plants are attractive alternatives, they can have disastrous consequences if they have an accident resulting in core damage. For that matter any release of radioactivity to the outside of the plant whether in the form of radioactive liquid, solid or gas could also have sever consequences.
Owning and operating a nuclear reactor requires great leadership, expert oversight, attention to safety, and planning. The reactor workers including the operators, the technical advisors, the technicians, the maintenance crew, etc. have to continuously receive training and their technical and mental competency verified. The reactor systems including pumps, valves, motors, etc., have to be properly maintained and sufficient spare parts should be available on site to assure continuity in power operations. Prior to reactor startup, sufficient nuclear safety analysis should be completed to estimate the weak links and the frequency and scenarios of potential accidents and their respective consequences. Based on those studies, plant modifications should be implemented to reduce the probability of such events. The expert oversight agency should assure completion of a detailed Final Safety Analysis Report (FSAR) prior to granting operating license to the plant manager/operator.
The question to be asked is, did the Islamic Republic follow all these steps (among others) to assure safety of the reactor, radiation workers, the public and the environment? The BNPP is a unique nuclear power plant and first of its kind as it is combination of a ~35 year old German technology and construction and a Russian reactor with questionable safety issues. Aside from the staggering cost of reconstructing this plant, what verifiable safety measures does the IR have to show? What is the estimated useful life of this very unique reactor? What is the predicted availability and capacity factor of this reactor? How long are the Russian consultants contracted to stay on site after the start of the power operations? What verifiable mitigative measures have been established (such as public cautions and warnings, evacuation strategy, decontamination strategies, emergency management planning, etc.), in case of a large release from the reactor? I doubt it very much if even very few of the above questions can be positively answered.
My friends, Iran definitely needs nuclear power to satisfy her growing demand for energy, but under the right leadership who values the safety, health and welfare of its people and environment.
Pedram: When we consider that the construction of Bushehr plant began 35 years ago, can we assume that it is still an economically viable project?
Azizi:The BNPP construction began in mid 1970’s and was close to completion during the 1979 revolution. As I mentioned above, the plant was ignored by the authorities and bombarded by Iraqis. I am not sure if the structural integrity of the plant especially the “modified” containment building is the same as what was originally designed. Note that the containment structure should be able to withstand the “worst case scenario” thermal, static and dynamic loads applied to it during an accident condition. I have not seen any feasibility analysis on the BNPP structural integrity. Aside from the structure, there may have been other equipment that were originally installed such as heat exchangers, pumps, valves, cables, transformers, etc. Some of this equipment may or may not have been replaced, but the fact is that even without actual usage, the failure rate of some of these equipment increase due to environmental effects such as humidity, heat, cold, etc. This increase in failure rate means more down times and more corrective maintenance that translate into more cost for operating the plant. Altogether, more than $4 billion have been spent on this plant that was supposed to be completed at a cost of about $1 billion. I can guarantee that the operational and maintenance cost of this plant will also be much more than a typical 900 or 1000 Mwe nuclear power plant due to its uniqueness, age and past history.
Pedram::One of the main difficulties of industries in Iran is to find and establish a suitable location for their installation. Do you think that Bushehr plant has a geopolitically and ecologically suitable location?
Azizi:When the initial contract was signed between Iran and Germany for the construction of Iran 1 and 2 (BNPP), many studies were conducted including the Environmental Impact Statement (EIS) and other environmental and ecological studies (such as seismic studies, etc.). While Bushehr has a very hot and humid weather with an abundance of sea salt in the air (potentially corrosive compound), it is seismically more stable than most of other locations in Iran. This is not to ignore the fact that in the future a military strike against the BNPP or a sever accident that causes breach of containment integrity could severely contaminate a large area of the Persian Gulf and the coastal region.
Pedram:Major nuclear countries are facing the on-going problem of getting rid of spent fuel. What standards should be observed in this regards and if they are by-passed what consequences could be expected?
Azizi:Nuclear waste is a great concern for several reasons.
1. Temporary storage: Usually the spent fuel assemblies are kept in the fuel pool (next to containment building) for the duration of reactor life (~25-30 refueling cycles). At this stage the plant owner should assure enough neutron absorber in “Refueling Pool” (such as Borated water) to prevent re-criticality accident.
2. Spent fuel transportation: Spent fuel is placed in specially designed casks and typically transported by truck or rail. There is always the risk of an accident resulting in rupture of the cask and release of radioactivity to the environment. In this case also, the transportation organizer should assure that the spent fuel remains sub-critical.
3. Spent fuel reprocessing: using re-processing facilities the built up Pu-239 and the residual U-235 can be extracted from the spent fuel and reprocessed for use as fresh the fuel. The amount of Pu-239 and U-235 in this process is not enough or economical to be used for a nuclear weapon, although it is not impossible either! Spent fuel reprocessing poses great danger of exposure to the radiations workers and environmental contamination if strict radiation work practices and radioactive waste handling process is not followed.
4. After separation of the useful Pu-239 and U-235, the remaining waste is either high level “Transuranic” waste (HLW) or low level waste (LLW). The LLW is usually shipped to special LLW processing facilities where they are packaged and buried in underground storage facilities (in the US LLW is shipped to States of Utah or Washington for processing or burial). The HLW requires special handling due to its high level of radioactivity. The HLW should be buried deep underground (about 3 Km or so) in an area where very little or no seismic activities have been recorded, the underground water table is non existent or considerably deeper than the burial site and there are traces of salt rocks at the burial site. The HLW is then placed in storage compartments and the compartments are sealed with “leaded” concrete blocks. Due to decay of HLW, the waste eventually melts the rock and remains there indefinitely. A new research however is being conducted in Europe where with the help of high energy laser they were able to eject a neutron from the radioactive isotope and therefore create a new isotope with considerably shorter half life. This experiment however is at it’s infancy and requires much more research and development in order to be useful and economical.
Pedram: If anything happens to Bushehr plant what would be the least and most impacts on the environment? What kind of precautions should be taken into consideration in these regards?
Azizi: For a typical nuclear power plant, the accident scenarios are evaluated by performing a “Probabilistic Risk (or Safety) Assessment” (PRA or PSA). A full PRA typically is composed of three levels of analysis in addition to an extra level of analysis called the External Events Analysis. The three PRA levels start with PRA level 1 which evaluates all the plant systems responses to various accident scenarios. The result of Level-1 PRA is a list of scenarios started with a certain “Initiating Event” and ending with various potential levels of damage to the reactor core. The initiating events could be in the form of plant transients such as Loss of Offsite Power (LOOP), Turbine Trip, Feed Water Pump trip, etc., or could be due to the reactor anomalies such as Loss of Coolant Accident (LOCA). Because of these potential accidents, nuclear power plants are designed with safety systems as well as emergency backup systems. Level II PRA analyzes the events in the containment building after core damage. It analyses the safety systems within the containment that are designed to prevent containment over temperature or over pressurization, potential for hydrogen explosions and finally, breach of containment integrity and consequent containment failure. Level III PRA analyses radioactive material release to outside containment, the formation of radioactive cloud or “plume” and potential effects on humans, animals, plants and environment. The External Events analysis also analyses potential of a catastrophic environmental or human made events such as earthquake, flood, tornado, sabotage or military attack on the plant and their consequences. In all these analyses, the weak points are identified and redesigned to reduce the probability of a catastrophic event.
As far as I am aware, PRA has not been done on the BNPP. Although many plants in the world just suffice to their established safety systems, but typically because those plants have many reactor years of operating experience their respective owner and overseeing agencies feel confident with their operation. BNPP however is very unique since it is a modified mixture of Russian and German nuclear technologies. It represents neither a true VVER reactor nor a Biblis reactor. Many modifications have been made to both the reactor and the reactor building to fit these two technologies into one. Because the BNPP is the first of its kind (and probably the last!) the PRA analysis is an absolute necessity. There are too many systems and operational unknowns in this plant that may not be obvious to the plant operators until something bad happens. Without knowing the details I would guess that the probability of an accident resulting in core damage is a lot higher than a typical ~1000 MWe Pressurized Water Reactor (PWR). The US Nuclear Regulatory Commission (NRC) requires that such a plant core damage frequency be less than one in 10,000 per year (1.0E-04/yr), I don’t think the BNPP comes even close to this number. Although the probability of a “Chernobyl” type containment failure is extremely unlikely for the BNPP (Chernobyl did not have a reinforced concrete containment building), because of all the modifications made to the containment structure and its surrounding structures, there is higher probability of containment breach in case of a sever accident and consequential core damage. The US NRC mandates that similar plants containment failure probability be less than one in 1000 (1.0E-03), but I think the BNPP containment breach probability may be much higher than this number. Finally, in case the BNPP containment is breached during an accident, there will most likely be a partial release of radionuclides from the containment (I don’t think a full release is very likely unless the whole containment dome collapses). In that case, depending on the wind direction and the outside temperature the release “plume” will rise to a certain elevation and start moving towards the wind direction. The plume will have fallout along the travel path in the form of heavier radioactive elements fallout or mixing of radioactive elements with air moisture and rain. Typically, because the wind direction is towards inland, the plume path will travel inland as well. This could potentially mean that the plume path could go over population centers which depending on the speed of the air mass flow the general population can be exposed to radiation in a short term or within a few days. Depending on the size of the plume and the rate of fallout, the rate of acute and latent exposure, and fatalities and injuries will vary. Some of the long term effects include increased cancer rates, birth defects, sterility in men and decline in general public health (for potentially several generations) as well as contaminated soil, plants and eventually ground water on the path of the plume.
It should be noted that even during the normal plant operation, lack of attention to safety and operational/ maintenance details could result in contained or uncontained release of radioactivity to the atmosphere and surrounding environment in the forms of gases, liquids and solids that could potentially contaminate the Persian Gulf coast as well as the surrounding farmland and communities who live around the plant.
Pedram: What international standards are available for constructing nuclear plants? Do the international agencies have the power of supervising these operations to make sure that all safety precautions are observed?
Azizi: Each reactor builder has to follow it’s respective government agency overseeing the nuclear activities standards. In the US for example, all commercial reactors are being regulated by the US Nuclear Regulatory Commission (NRC) and all government related nuclear facilities are being regulated by the Department of Energy (DOE). Each of these agencies have their own standards and requirements for safety and safeguard of the commercial or government facilities, but some standards such as maximum allowable levels of exposure to public or radiation workers are the same through the Code of Federal Regulations (CFR). The NRC establishes standards for construction and operation of commercial nuclear reactors, and grants construction and operations license to the plant owner. These processes are the same in other countries with nuclear plants, but since many of the plant constructors are American, construction and operational guidelines of the nuclear power plants in other countries are similar to the US standards. The IAEA has the responsibility of oversight of the nuclear safeguards over the member countries, but they do not impose any nuclear safety regulations on the member country.
Pedram: Are the operations of American and European nuclear under any observations? Or, just like Iran, there is no way for the environmental experts and concerned people to watch their operations
Aziza: In democratic countries such as the US, European countries and Japan, public hearings are held prior to construction license. People can review the proposed plant’s environmental impact statement (EIS) as well as the general advantages and disadvantages of the plant. There are special interest groups such as the Union of Concerned Scientists, environmental advocates, etc., that look at the technical aspects of the plant and participate in the public hearing. After the plant is licensed and built however, its perimeters are tightly guarded and strict security is imposed to prevent possibility of sabotage and any danger to the plant operation. The NRC however has the right to inspect and audit the plant operation or personnel and can impose heavy fines on the plant owners if the plant fails to follow the mandated standards.
Pedram:Taking into consideration the extent of endeavors to produce clean energy in developed countries, what is the worldwide situation in the field of building nuclear plants? What kind of changes one can detect in this regards?
Azizi: You have to understand the fact that the fossil fuels especially the global oil reserves are shrinking. (See the chart below). The green energy including solar, wind, hydroelectric, geothermal, etc., have operational and economical limitations. For example, solar energy is being utilized in several countries including the US and Spain. Although both of these countries have invested in solar energy technology such as photovoltaic technology for residential and limited industrial usage or solar power plants (~ 10 Mwe) for small towns, an economical, low maintenance plant that can provide more than 100 Mwe is being studied. Note that I am currently involved with the design and development of such a plant.
There are about 440 nuclear power plants worldwide. While there were no new construction permits given to any utility in the US after the Three Mile Island (TMI) accident in 1979 (only a couple of plants under construction were completed in early 80’s), some countries such as Japan, China, Taiwan and a few other countries built nuclear power plants ever since. There are currently a few nuclear power plants under construction in various parts of the world.
Under a stable government, with expert oversight and strict regulatory guidelines on reactor construction, operation and safety, nuclear power could be extremely beneficial to the development of a country. A good example is France that uses more than 80% of its electric power from the nuclear power plants.
Pedram: Compared to other kinds of energy, and considering the volume of investment, how economically viable is the nuclear energy?
Azizi: As I mentioned above, nuclear power plants can be very beneficial to the growth of a country. Standardization of the plants could reduce the capital cost while implementation of established and strict maintenance procedures can reduce the recurring cost. However, Bushehr Nuclear Power Plant in my mind is neither economical nor safe, and the reason is primarily because this plant is not a standard plant with non other plant like it. In my opinion, the real intent behind completing the construction of this (very costly) plant after the 1979 Islamic Revolution was not necessarily to provide energy but rather to jump start the Islamic Republic nuclear ambitions.
* Mr. Massoud Azizi is a principal nuclear engineer and a technical fellow at the Pratt & Whitney Rocketdyne (PWR) division of the United Technologies Corporation (UTC). He received his Bachelors Degree (B.S.) in Civil and Environmental Engineering from Utah State University and Masters Degree (M.S.) in Nuclear Science and Engineering with specialty in Radiation Protection and Shielding from the Idaho State University (ISU). He also taught "Mechanics of Material" at the ISU.
After his graduation, Mr. Azizi worked as Structural Engineer for a company in Idaho. He then started work at Energy Incorporated in Seattle, Washington as a nuclear safety/reliability engineer. Later, he joined Arizona Public Service Co. (APS) in Phoenix, Arizona as Lead Engineer for the Probabilistic Risk Assessment (PRA), System Safety, Reliability & Maintainability group at Palo Verde Nuclear Generating Station (PVNGS). Mr. Azizi then joined Rocketdyne in Southern California. As a Principal Engineer and a technical fellow, Mr. Azizi’s primary responsibilities includes extensive leadership in the areas of
* Terrestrial nuclear programs with Department of Energy’s (DOE) ,
* Space Nuclear Safety, System Safety and Reliability projects for Department of Defense (DOD), DOE,
NASA and JPL,
* International Space Station (ISS) with NASA,
* Rocket propulsion systems with NASA and the US Air Force,
* Terrestrial energy systems such as the Concentrated Solar Power and Coal Gasification programs.
* Mentoring other engineers in various areas of his expertise
Mr. Azizi has published more than 30 papers many of which have been presented in national and international conferences.
Mr. Azizi has received many honors and awards including the US Secretary of Energy, NASA and the US Air Force awards. He invented and patented the concept for a Remote Tracking and Locating System and is member of the American Nuclear Society, National Management Association and the American Society of Quality.
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