[BigV]

My point is that the language in the article is factual and neutral, just how I expect a journalist to convey the information. I find your substitutions not neutral, and some are hyperbolic.

...start the delicate and risky task (untested and dangerous)

so, you're saying "dangerous" is more apt than "risky". Ok, a judgement call, I'm fine with your choice I guess. Delicate vs untested? How do you know it's untested? I'm certain, we're all certain the task is delicate, requiring care. I don't think your choice is better, and I'm not even sure it's true. I think the things required to accomplish this task have been tested, element by element even if it hasn't been done end to end.

...to release radioactive materials beyond the plant(environmental disaster)

Your choice of "environmental disaster" is hyperbole and speculation. The sentence as it stands is not euphemistic, it's just factual.

So in other accident scenarios that are not the worst case, no release beyond the plant, no "environmental disaster". I'm not saying what will happen, I'm only parsing the text of the article, just as you did when you found so many euphemisms.

...very big risks involved(extremely dangerous)

very big vs extremely and risks vs dangerous... Ok, a wash. I don't find your choice noticeably better, but I don't find the original phrase euphemistic either.

...a more dangerous chain of events (environmental disaster with lethal/genetic damage to people)

substituting "environmental disaster with lethal / genetic damage to people" for "more dangerous chain of events" is a problem for me for two reasons. firstly, that story's quoting someone involved in the project--changing their words in the story would be dishonest. Now maybe you're quarreling with the words spoken by the person imagining what might happen, but he chose his words, expressing his thoughts. secondly, it seems quite plausible that there might be an accident that wouldn't have the dramatic results your de-euphemism suggests. **could** it be the end of the world as we know it? I guess so. to define a range of what could happen that way is one way of couching it. but it doesn't seem like a neutral way, it seems like the opposite of a gentle, bland euphemism; it seems like hysterical scaremongering.

My point, since you asked, is that I like my journalism fair and balanced. I don't like it too bland (filled with euphemisms) or too spicy (filled with inflammatory language). I found the article neutral, fact based and unemotional.