Japan will start releasing treated and diluted radioactive wastewater from the Fukushima Daiichi nuclear plant into the Pacific Ocean as early as Thursday — a controversial step that the government says is essential for the decades of work needed to shut down the facility that had reactor meltdowns 12 years ago.
Holy shit, it’s been 12 years already? 2010-2020 was like a fever dream.
What are the alternatives?
Honestly, not much in the way of alternatives. Tritium is very, very difficult to remove from water. Basically the only option, aside from discharge, is to store it in tanks and wait for enough half lives to elapse that the tritium effectively just decays away on its own. The half life of tritium is just over 12 years, so that’ll still be a while longer, and that gets expensive (in terms of both storage costs and space costs). However, tritium is not particularly dangerous, especially at low concentrations.
As usual with radioactive liquids, dilution is the solution. And Japan has diluted this liquid to 1500Bq/liter, far short of their internal legal limit of 60,000Bq/liter, and even far below the WHO limit of 10,000Bq/liter.
It’s been 12 years, 5 months, how much longer are we talking about?
Usually to consider radioactive sources “gone” you have to wait at least 5 half lives (which makes it 99.875% gone), which would be 60 years in this case.
12 years? Holy shit that’s insanely fast. Can you even go near that stuff, nevermind release it into the ocean?
100% yes, it is safe. Tritium is a very weak beta emitter, so tritium itself cannot emit radiation strong enough to even penetrate your skin. According to the NRC, drinking water for an entire year from a well contaminated with 1600 pCi/ml of tritium (comparable to levels identified in a drinking water well after a significant tritiated water spill at a nuclear facility) results in a radiation dose of 0.3 mrem. That is 12 times lower than the dose you receive from a cross country flight (DC-LA and back). The federal limit (in the US) for radiation workers is 5 rem per year. 0.3 mrem is 0.00003 rem. This release of tritiated liquid by Japan is completely safe, and very far below any regulatory limit.