I learned that the spent fuel storage is pretty trivial for a few reasons:
1. The amount of fuel waste produced by a reactor is volumetrically tiny. So it's not too expensive to just have a relatively small guarded yard of sealed storage casks next to the reactor, where the fuel can sit and decay until safe for offsite disposal (typically around 60 years).
2. Safe waste storage containers are relatively easy to make. Most containers only need to be a thick stainless steel inner liner and a stainless steel outer liner filled with a special mixture of concrete. The nuclear waste is dropped in, the lid is bolted shut, then the container can be safely left in a guarded open yard for >100 years. They are safe by virtue of just having ridiculously thick welded stainless steel walls. We designed them to fall off a train going over a bridge, fall 300ft onto solid rock, and not break.
3. Reactor technology keeps getting better at extracting more energy from fuel. So what was "waste" in a past decade, can be put back into a reactor that is better at pulling energy out of the fuel. For this reason, there hasn't actually been much actual "fuel waste" in the history of the nuclear industry. It's all just being stored for future use by better reactors.
https://gordianknotbook.com/wp-content/uploads/2023/10/gordi...
- nuclear waste, after a period of the order of ~10e2/3 years is only dangerous if ingested. So it's as dangerous as any other poisonous substance after that point. There is no need for radiation shielding from that point.
- nuclear waste is very dense and so physical surface storage is cheap, and a solved problem (see: dry storage casks). We can fix leaks if/when they happen. Waste is concentrated
- current nuclear power stations (light water reactors) burn about 3% of their fuel leaving 97% unused in waste. There are nuclear power solutions which would burn most of the fuel (leaving very little for waste). So if we developed these technologies (see molton salt reactors being one of them) then nuclear waste would no longer be called "waste" as it would suddently become an extremely valuable feedstock for use in reactors.
- related to the prior point: why is it that we think we will not find a use for this very valuable and rare reasource in the future. We should think of nuclear "waste" storage as "rare element storage" which will be very useful under some states of the world. We just don't know how yet.
- as with any technology it should also be compared to the alternative when considering it's fitness: waste from the alternatives is far worse
https://world-nuclear.org/information-library/nuclear-fuel-c...
Basically, nuclear waste from power generation is a much smaller problem than people assume it to be, the solutions for managing it are already in place, and there have been few/if any accidents that have ever caused contamination from waste disposal.
Also I'm not an industry shill, but orphan sources from industrial/medical radiography have killed and injured more people than nuclear plants and their waste. Yet there's hardly the amount of opposition to those systems that you see for nuclear power, despite nuclear power having a far more significant impact on the healthiness and stability of global populations if we stopped banning it.
Realistically deep geologic storage is absolutely fine, and even if it's not happening now, all of the waste can be safely stored above ground for hundreds of years.