Harry, on the other hand, had liked them; they put him in mind of palm trees and white sand, and he hoped that, wherever Sirius was (Sirius never said, in case the letters were intercepted), he was enjoying himself.
Their dead bodies float downstream until the flood recedes, and leaves them stranded on a bar or shore where they lie, half-buried in the sand until they decay.
After that, for days, thousands of tons of clay, sand, boron, and dolomite, were dropped by helicopter into the burning reactor to quell the fire, but also to try and prevent the spread of radiation.