Why were Russian Soldiers digging a Trench around Chernobyl?

 This is a really insane thing to do if you know anything about radiation at all.

If you did this without a gas mask to filter out radiated particles of dust then likely ALL these soldiers will die within the next 20 to 30 years caused by one or more radiated particles lodged in their lungs.

Something like this happened to John Wayne and many members of his crew on a movie they made I believe it was in Nevada? or nearby that was down wind of a nuclear weapons test site. This is what actually killed John Wayne eventually.

So, all the trenching Russian Soldiers likely will die over the next 10 to 20 to 30 years of a radiated particle or many radiated particles of dust or dirt lodged in their lungs of the dust from digging a trench around Chernobyl.

If I wanted to dig a trench around Chernobyl I would choose a Backhoe and a fully covering gas mask built for filtering out all radiated dust particles. You might have a way to survive doing this if you left the backhoe there that had an enclosed cab and maybe a heater or air conditioner with an air filter on it. But, these soldiers likely all might die eventually from radiation poisoning if they weren't at the very least wearing gas masks to filter out radiated dust and dirt particles.

Also, were they creating a defendable perimeter or planting explosives or nukes to later set off remotely to prevent anyone from living in Ukraine or that area in the future?

The whole thing doesn't really make any sense on so many different levels does it?