What the US Navy actually does with its spent reactor coolant, is to make concrete out of it. The concrete as well as the mixer are buried at Hanford. I don't

What the US Navy actually does with its spent reactor coolant, is to make concrete out of it. The concrete as well as the mixer are buried at Hanford. I don't see why Japan couldn't do the same. I expect it already does this, with the coolant from its other reactors. The water used to mix cement doesn't evaporate, that is cement doesn't dry, it sets or hardens. The binder is a chemical known as "Portland Cement"; it hardens when it combines chemically with water.