Their reasoning in Westminster, is that the waste will be stored securely away from highly populated areas, namely large cities.
Even though Sellafield Nuclear Power station, is not quite within the Lake District National Park, its close enough to pose a risk, if any existed.
Sellafield produces large amounts of toxic waste, and no doubt stores a fair amount of it as well.
The population on the West coast of Cumbria is tiny, hence the sighting of the station there in the first place, as well as its coastal location to aid cooling of the reactors.
Its almost inevitable that the waste will end up in the areas of small population density, Snowdonia or Cumbria.
Measures will be so tight in the methods used to store the waste, that it does not really matter which part of the country is used.
With the potential terrorist risk of storing it near a major city, its inevitable that areas with tiny population density will be chosen, and there's nothing new about that, as its been stored within a National Park for over fifty years, with no health issues.
Nobody in Gwynedd, with its two Power stations, Trawsfynydd and Wyllfa, complained about the presence of these contoversial buildings, so close to the small population.
They provided much needed employment, and huge amounts of electricity, which every one needs.
Trawsfynydd has had its Nuclear Power Station and associated waste since its opening in March 1965, and nobody has complained about the toxic waste being stored there, and its in one of the most picturesque locations in the whole of the Uk.
The waste has got to be stored away from densley populated areas, so its inevitable the National Parks will be used, as there are very few major towns or cities within a certain distance of Cumbria or Gwynedd.
Anyway the associated risk is so tiny, that it does not matter where the stuff is stored, the safety precautions are so tight, that any health issues are almost non existent.