https://en.wikipedia.org/wiki/Operation_Crossroads was in July 1947, so chances are fairly good its data was used to write “The Effects of Nuclear Weapons” (couldn’t find a first edition online to verify that)

March 1, 1954 was 3 years after this ship was scuttled, so mentioning it is irrelevant.

Also, dumping waste in sea may be stupid, but it was the norm for decades. And yes, that includes dumping nuclear waste. https://en.wikipedia.org/wiki/Ocean_disposal_of_radioactive_...: ”From 1946 through 1993, thirteen countries (fourteen, if the USSR and Russia are considered separately) used ocean disposal or ocean dumping as a method to dispose of nuclear/radioactive waste“