This highly informative piece explains the nuclear power plant decommissioning process being reviewed currently for San Onofre, along with other background information.
Since the Japanese earthquake and tsunami disaster in March of 2011, the world has been viewing the nuclear power industry with close scrutiny. Germany for example hastened to shut down all of their nuclear power plants, including those built in more recent years with newer technology.
The United States followed suit with public pressure and began reviewing nuclear power facilities more closely. One such location is San Onofre in southern California
The Nuclear Regulatory Commission (NRC) whose sole purpose is to “ensure the safe use of radioactive materials for beneficial civilian purposes while protecting people and the environment” had the facility inspected and found it in need of upgrades. Multiple millions of dollars were spent on upgrading and repairing the facility with updated safety measures. Upon closer inspection, it was determined that additional repairs were necessary. This induced the need for a cost/benefit analysis to determine if the cost of the needed repairs would derive an appropriate benefit. The determination indicated that the cost of repairs would not derive the needed benefit in the final result. The upgrades would be too costly to keep an aged facility functional and as a result the facility was deemed no longer economically viable.
Each nuclear power plant has a license to operate. Similar to an older vehicle, after the plant reaches a certain age, additional maintenance and repairs are required. If the plant is deemed no longer economically viable, the license is not renewed and the process of decommissioning begins.
I recently had the opportunity to meet with a very knowledgeable expert on this topic. Jay Tarzia is Executive Director to Radiation Safety & Control Services (RSCS). RSCS is advancing the radiation safety project management for nuclear decommissioning, handling aspects of every nuclear plant decommissioned in the past 15 years. They have expertise in all stages of the decommissioning process, from pre-planning, to execution, to radiation waste management, to releasing the land for public use.
Mr. Tarzia provided an in-depth explanation of the decommissioning processes used throughout the world and in the United States.
There are three types of processes that can take place for decommissioning such a facility depending on the amount of money in the decommissioning fund that was earned during the life of the facility.
- Decom is the process of dismantling the plant as quickly as possible, disposing hazardous waste materials, taking buildings down and reclaiming and reusing the land. This is the most chosen option for the past 20 years. This is the most popular option because the facility and all after effects are removed as quickly as possible without the need to keep the site in storage.
- Safestor is the process of putting the plant in a layup mode for 20 to 50 or up to 60 years. The plant is taken down after that storage period. This option might be chosen when the decommissioning fund is not fully funded. If the plant is to be decommissioned before it has earned enough funds to properly dismantle, the then current fund may be invested for a number of years while the facility is in storage to earn the amount necessary for proper decommissioning. This option has not been chosen in the United States in the last 20 years or so. Although Chrystal Rivers in Florida is reviewing this option.
- The third option called Entomb, is a process of entombing the facility. This tomb or sarcophagus covers the facility for up to 300 years. This is not considered a viable option for any of the sites in shut-down mode recently. In Chernobyl Russia they don’t have the funds to decommission the reactor and they are building a sarcophagus over the reactor. In 200-300 years if the funds and ability exists to clean it up they will uncover it and dismantle and clear the site.
In the United States the decom option is the most used though occasionally there is a delayed decom where some plants have been in a storage or layup mode for up to 10 years before they are fully decommissioned.
Cost estimates for San Onofre are still being reviewed to determine the most viable option. Decom is being strongly considered because it is the best option for the public. This option will remove any hazardous waste and is the quickest option to return the majority of the lands for public use or whatever the landowner determines will be the next use for that land. Since that land is owned by the government it would possibly go back to the military base as part of Camp Pendleton though that is yet to be determined.
During decommissioning, the facility is dismantled. The materials are tested for hazard ratings. The ratings determine in what manner the materials are dealt with. The majority of materials are metal and cement, which are cleaned, tested, segregated by hazard rating and those that are not hazardous are disposed of in a manner similar to a commercial construction site. Materials classified as hazardous are handled based upon the hazard rating. Certain locations are set up to receive varying levels of hazardous waste. During the decommissioning process the most hazardous material is the remaining fuel. The most hazardous materials are to be shipped to a facility designed to entomb the materials in secure underground protected structures. Repeated testing is done on the ground in and around the area to ensure radioactive levels are within safety requirements. Once the surrounding area meets the safety requirements, the radioactive license is removed and the land returned for purposes other than the power plant.
A highly secure area was being built in the Yucca mountains of Nevada to take the most hazardous waste. The Yucca Mountain Nuclear Waste Repository as designated by the NWPA Amendments of 1987, was to be a deep (2,100 feet) geological repository storage facility for spent nuclear reactor fuel and other high level radioactive waste. Federal funding ended in 2010 for political reasons. For this reason, fuel now must be either stored on site or sent to one of a number of facilities across the country. The preference is a single location, which was the goal with the Yucca facility.
Until the spent fuel is removed, a concrete pad is created at the site with a secure storage container. The fuel is placed in this secure container, which is completely secured by varying levels of fencing, high tech monitoring and a 24/7 security force. The majority of the land is cleared and free, leaving only this storage area.
Other countries are ahead of the United States in the process of storing spent fuel and radioactive materials.
Fully decommissioning a nuclear facility used to take 10 to 15 years. Now that amount of time has been reduced to five to ten years because of newer technology and improved processes. The goal is to do a plant like San Onofre in seven to eight years. A large portion of the decommissioning has already taken place on unit one, but units two and three are larger reactors so more time will be invested.
Public opinion can play a key role in what happens to these power plants. Southern California citizens have shown to be interested in and determined to take a more active role in environmental impacts of energy sources over other parts of the country.
I asked Mr. Tarzia if nuclear energy is hazardous. He responded with “the answer to the question is that there is hazard with nuclear power just as with coal and so forth. The real question is if the energy that is used to make the electricity is under control and the hazard is minimal”.
“We know there have been issues in the last 30 years starting with Three Mile Island, Chernobyl and the incidents in Japan,” he continued. “The nuclear program in the U.S. is the safest in the world. We deal with making and using radioactive material in a safe manner. For the past 30 years of my work experience and my company’s experience we can tell you it’s the safest in the world. “
Tarzia went on to a more detailed answer to the question about how environmentally safe is nuclear energy. “The answer to the question and what I believe and the most technically educated believe is that it is a very clean energy source and the impact is lower than other methods. When we burn coal we put chemicals and toxins into the air. If you look at the entire situation the amount of electricity from the small managed risk is more value to the public.”
The public plays an important role in nuclear energy. Any readers with questions or concerns are encouraged to contact the NRC, their local spokesperson or any number of groups. Some of the groups and their links are listed below:
There are many other organizations to contact and research and who are willing to speak with concerned citizens.
The next segment coming in this energy series relates to solar power products.