[Lamplighter]

euphemism |ˈyoōfəˌmizəm|
noun
a mild or indirect word or expression substituted for one considered to be
too harsh or blunt when referring to something unpleasant or embarrassing

Within my post, above

...start the delicate and risky task
...to release radioactive materials beyond the plant
...very big risks involved
...a more dangerous chain of events
...a significant release of radioactive material

Within the article:

...tense operation
...complicated, potentially hazardous
...a threat that has hung over the plant
...severe enough to force workers to evacuate