Yucca Mountain has been in the news recently for it being touted as a potential site for nuclear waste storage. This, understandably, has caused some controversy in the media, but is this just another example of a media-generated "storm in a teacup"?
With that in mind, is the recent controversy over the use of Yucca Mountain for nuclear waste storage just hype? Or is it a genuine potential future environmental disaster?
Give nuclear energy a chance
Nuclear fission is widely considered as one of the most efficient, 'clean' and safe methods for generating electricity that mankind has ever produced. Whilst it tends to attract bad press, in part thanks to its association with nuclear weapons and very rare disasters when things go wrong, we really should give it a fair trial.
There can be no doubt that mankind needs to move away from carbon-based fuel sources for future sustainability. This is due to the finite nature of the fuel as well as potential environmental impacts from its continued use.
With a vast array of alternative energy sources being developed at the moment, perhaps the most realistic solution is to use nuclear energy. Renewable energy generation, whilst promising, is, after all, inherently intermittent by its very nature.
Solar power can only be relied upon when the sun shines and wind when the wind blows, for example. For these solutions to become viable as replacements for combustion-based energy sources, reliable energy storage solutions will need to be developed, and in quick order.
Nuclear power, on the other hand, harnesses the power of atomic fission to release enormous amounts of energy for the consumption of a very small amount of physical fuel. Sadly any mention of it will immediately conjure up images of mushroom clouds, post-apocalyptic dystopias and roving bands of mutants.
Despite the fear-mongering around nuclear fission, accidents are actually relatively rare events. Since 1942, there have only been three major nuclear accidents in history (Three Mile Island, Chernobyl, and Fukushima).
In fact, according to the World Nuclear Association, of over 17,000 cumulative reactor-years in over 33 countries, these are the only three major accidents. That's a pretty impressive safety record.
If we are serious about transitioning away from using 'fossil fuels' for our energy needs, we need to look seriously at existing energy generation sources, like nuclear. Many believe that nuclear fission is, arguably, the only developed energy source that will, in the long run, allow us to transition away from carbon-based energy generation.
Despite this, there are some genuine real concerns about nuclear waste. Is this nuclear fission's Achilles heel?
Putting nuclear waste into perspective
Like all industries, energy generation inherently results in the creation of waste. For combustion-based energy generation, many can easily understand this.
But renewables are not immune from this either.
Wind turbines, solar panels, and other renewable technologies need to be built from raw materials and consume energy to do so. Often times this involves the use of electricity from existing traditional power plants - that generally use fossil fuels.
Despite what you might have been told, they are also not completely environmentally friendly during their lifetimes.
So is the bad press that nuclear fission receives justified?
Genuine concerns about the storage of nuclear waste need to be put into perspective. Whilst yes, it is potentially inherently very dangerous in and of itself, the nuclear industry is one of the most highly regulated in the world.
From cradle to grave, nuclear fuel must be handled, transported and treated according to very strict controls. Waste generated by nuclear power is also relatively very small when compared to other thermal electricity generation technologies.
"For radioactive waste, this means isolating or diluting it such that the rate or concentration of any radionuclides returned to the biosphere is harmless. To achieve this, practically all radioactive waste is contained and managed, with some clearly needing deep and permanent burial. From nuclear power generation, unlike all other forms of thermal electricity generation, all waste is regulated – none is allowed to cause pollution." - World Nuclear Association.
The main issues around nuclear waste are to ensure that it is:
1. Safe from theft;
2. shielded to prevent radioactivity emission;
3. must prevent leaking into soil and water sources;
4. Needs to be insulated damage by natural disaster, and;
5. It needs to be hidden in such a way as to prevent discovery and accidental misuse by future generations who might not understand its danger.
Of these, the most immediate danger is leaching from sealed storage containers (dry casks) through running water. For this reason, long-term safe storage facilities are needed around the world, especially in the United States.
This is why sites like Yucca are essential if nuclear power is to be a major component for the US's energy mix.
But what about sustainability? Is nuclear energy actually sustainable?
The generally accepted definition for whether something is sustainable or not tends to be:
"Meeting the needs of the present without compromising the ability of future generations to meet their own needs”.
This tends to imply providing a resource, energy or not, for generations to come, perhaps even on civilization-spanning time spans.
With regards to energy generation, nuclear fission from uranium and plutonium can be considered sustainable. It does, after all, meet the criteria dictated by the above definition.
Nuclear reactors need only a small amount of fuel to release disproportionate amounts of energy. As Enrico Fermi noted in the 1940s, nuclear reactors operating with 'fast' neutrons, could conceivably provide in excess of one hundred times more energy from the same amount of uranium than current 'thermal' reactors.
To date around 20 'fast' reactors are in operation around the world. It can be argued that these should be made our priority for a future carbon-free energy mix.
And that's before we even begin to discuss the potential for Thorium reactors.
Why Yucca Mountain is a good choice for nuclear storage
But despite all this, nuclear waste needs to be dealt with. Solutions for 'disposal' usually involve burial on- or close to the surface or deep underground (at depths between 250 and 1000 meters for mined repositories or 2-5km for boreholes).
This can either be onsite at power stations or in a separate location away from the production facility. There are various such locations around the world ranging from Drigg in Cumbria in the United Kingdom to one of five disposal sites in the United States for low-level waste (> 4 giga-becquerels per ton).
LLW tends to include things like contaminated tools etc.
High-level waste, like spent fuel, tends to be stored to allow radioactive decay and heat to dissipate to make them safer to later handle. Often times, this spent fuel can be recycled (or reprocessed) to reuse any uranium and plutonium therein.
Else it is also disposed of in deep geological disposal sites.
This is where we, finally, get on to the subject of Yucca Mountain. This site was designated in the Nuclear Waste Policy Act of 1982 as an ideal site for deep geological storage of nuclear waste.
It was highlighted as a great place to store US generated high-level waste and spent nuclear fuel. Its use was approved in 2002, but funding was cut in 2011 under the Obama Administration.
This has since put pressure on nuclear waste producers in the United States. Around 90,000 metric tons of waste require deep disposal and are currently being held in temporary storage facilities.
It is becoming more and more urgent for the US to find a site for the safe long-storage of this waste. That's why it was hoped Yucca Mountain was the safest solution.
To this end, the Trump Administration, in May 2018, attempted to reopen the Yucca Mountain for nuclear waste disposal. The House of Representatives had voted to restart operations there but were ultimately defeated.
In the meantime, nuclear waste will continue to be stored indefinitely on-site in dry cask storage in steel and concrete vessels.
The site, in an arid desert 100 miles (160 km) from Las Vegas, has very little precipitation meaning water infiltration and contamination is minimal. It is also made of dense volcanic rock which contains small pores further restricting rainwater infiltration.
Many experts agree that Yucca is, in fact, an ideal site for HLW radioactive waste disposal. But this, and other expert advice has generally fallen on deaf ears for protestor groups and prominent individuals.
In addition, waste would be stored far above water sources in the mountain. These features would effectively shield the waste and prevent the release of radioactivity.
It’s unclear whether a nuclear waste repository will be built in the near future, but it’s increasingly clear how necessary and how difficult the process will be.