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What Do We Do With Our Nuclear Waste?

Posted on 11 December 2014 by Jerry

The U.S. leads the planet in disposing of nuclear bomb related waste at its one of a kind Waste Isolation Pilot Plant (WIPP) outside Carlsbad New Mexico.  This facility was featured in an earlier June 2014 article entitled “A Nuclear Explosion in the U.S. in February 2014?”

Unfortunately this article does not include descriptions of the environmental problem of having no permanent underground sites anywhere in the world to store high-level, power-related nuclear waste.  We continue to not clean up after ourselves at our nuclear power facilities.

There are over 460 nuclear power plants around the world.  A survey of nations shows many plans for underground national nuclear storage sites, none of which have been built.  The vast majority of these plans represent facilities to be constructed by 2025 or later.

Nuclear waste from power plants is characterized in four categories: Exempt waste and very low level waste, low-level waste, intermediate-level waste, and high-level waste.  While there is not an estimated figure that represents the total worldwide annual nuclear waste, we do get some sense of it from a Congressional Research Service report.

According to the report “There were 62,683 metric tons of commercial spent fuel accumulated in the United States as of the end of 2009.”   Further the report identifies that 48,818 metric tons were stored in pools (78%), 13,856 metric tons were stored in dry casks (22%) and that the total increases by 2,000 to 2,400 tons annually.   These figures do not include the weapons grade nuclear material stored at WIPP.

Some high-level waste goes through two processes.  First, spent fuel rods are kept in a pool of water on-site for at least a year.   Normally however, the spent rods are kept in the pools many years in order to cool them and provide protection from radioactivity.  These pools use reinforced concrete that is several feet thick in steel liners to store spent rods.  Many power plants never remove these spent rods from the storage pools.

Another option is to move the spent rods from the storage ponds to dry casks after they have cooled at least five years in one of the ponds.  Then the cooled and less radioactive spent fuel rods are ready for a more long-term storage solution.  A Stanford University web site states, “Dry Casks typically have a sealed metal cylinder to contain the spent fuel enclosed within a concrete or metal outer shell to provide radiation shielding.”

While the dry casks represent an enhanced level of safety over the pools with respect to accidents or terrorists, they are still more vulnerable than long-term underground storage.  Underground storage is the best possible solution according to an international scientific consensus.  This storage is generally focused on a period of 100,000 years.  Any longer time horizon is difficult.  Some would argue that as a practical matter 100,000 years is too long.

This ignores however that the stored rods would contain very radioactive elements.  Included is cesium-137 and strontium-90 have half-lives of 30 years after which they are only half as radioactive.  Plutonium-239 has a half-life of 24,000 years

The World Nuclear Association describes a few countries that have plans.   As an example the “Swedish proposed KBS-3 disposal concept uses a copper container with a steel insert to contain the spent fuel. After placement in the repository about 500 meters deep in the bedrock, the container would be surrounded by a bentonite clay buffer to provide a very high level of containment of the radioactivity in the wastes over a very long time period.”

Their report continues, “Finland’s repository program is also based on the KBS-3 concept. Spent nuclear fuel packed in copper canisters will be embedded in the Olkiluoto bedrock at a depth of around 400 metres.”  A difference between country plans is the underground medium that is selected as the safest place for storage.  Some countries prefer salt deposits, others want granite and still others have selected clay.

This is yet again another example of a problem that we have refused to resolve over the last three decades.  The permanent underground storage is a more long-term solution than any other option and yet the world is incapable of moving on this solution.

Even though we can all agree that an underground storage site is desirable understandably no one wants one in their immediate vicinity.  In the U.S., after spending tens of billions of dollars, we abandoned the Yucca Mountain solution due to political opposition from the Nevada political establishment.

As long as we side step this long-term (semi) solution, nuclear power will continue to be controversial and more dangerous and costly than any solar or wind array.  Nuclear is still a better option than coal but we have to break the logjam of resistance at geologically acceptable sites before it becomes a viable alternative that falls on the “green” list of acceptable options.

A final solution is that citizens of each country must overwhelm political resistance from other people living near a geologically attractive site.  This is where the needs of the many out-weigh the desires of a few.  In the case of the U.S. this means we should insist that Yucca Mountain be made available for this nation’s long-term underground storage.

The other option is that the U.S. and other countries of the world agree on the optimum storage site in the world.  Then they collectively have to provide sufficient incentives for that country to step forward and volunteer to house the world’s nuclear waste underground storage site.

As a postscript to the earlier article about the nuclear explosion and contamination at the WIPP facility, the Columbus Dispatch has reported $54 million in fines levied by the government of New Mexico on the federal Energy Department.  These fines are largely because the WIPP and the Los Alamos lab did not follow the Energy Department’s own guidelines about handling nuclear waste.  It is reported that the Federal government will spend about $200 million more to eliminate radiation contamination at the WIPP facility.

At issue is the unsafe handling of a canister of waste that was sent to the WIPP by the Los Alamos labs.  This canister ruptured in a storage room and contaminated more than 20 workers at the facility.  The clean up has forced closure of the WIPP.  Some say the closure is for an indefinite amount of time.

Use the following links to access additional information or the source documents for this article.




http://www.nei.org/Knowledge-Center/FAQ-About-Nuclear-Energy (click on Safely Managing Used Nuclear Fuel)







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