Forum adverts like this one are shown to any user who is not logged in. Join us by filling out a tiny 3 field form and you will get your own, free, dakka user account which gives a good range of benefits to you: No adverts like this in the forums anymore. Times and dates in your local timezone. Full tracking of what you have read so you can skip to your first unread post, easily see what has changed since you last logged in, and easily see what is new at a glance. Email notifications for threads you want to watch closely. Being a part of the oldest wargaming community on the net. If you are already a member then feel free to login now.

Basically which Marine types are the ones whose job is to disarm enemy mines, mine routes the enemy may use, handle explosives, destroy bridges and road to slow the enemy down, build up bridges for their force to cross rivers, get rid of obstacles in order to facilitate the movement of their own forces, etc...

I don't know that the role really applies so much with Marines, whose modus operandi is pretty much "slam down onto the planet and brute force to the objective before the enemy knows what hit them". They don't usually have the need for disarming traps, building bridges and so forth.
That said - Infiltrators, Incursors and Scouts seem to be best equipped to handle that role.

 Super Ready wrote:
That said - Infiltrators, Incursors and Scouts seem to be best equipped to handle that role.

I'll second that - overseen by Techmarines.

The issue is that the game doesn't consider the possibility to disarm mines, destroy roads and so on, because it is focused on that phase of a battle we could call the final assault, so there aren't combat engineer among the space marines. Maybe it would be interesting inserire that possibility in Epic Armageddon, but I think it would be difficult add that feature in Warhammer 40,000. Anyway I agree with Super Ready: scouts, infiltrators and incursors could do those tasks, while in my opinion the techmarines should be used to sabotage industrial and power plants or other assets like these.

This is work best left to Chapter serfs, and Servitors overseen by a Techmarine.

Honestly, it's not something the game really considers, and when it does, it generally assigns such tasks to Techmarines, no matter how little sense that makes.

Marines unfortunately are described and portrayed in just about literally every possible form of combat, including attritional siege warfare and direct assaults on entrenched defensive positions. Minefields are something they only worry about when there's a narrative hook for it. Otherwise it gets handwaved away, like where do marines carry more bolter magazines than the single mag in their weapon?

I suspect that basic demolition skills, both setting and disarming are learned in the 10th company during scout training. So every marine should be able to plant a melta bomb to drop a bridge or string up some grenades.

Larger scale or more complicated jobs would probably require a techmarine, or someone who might have studied with one to pick up a few extra skills.

At the Kill Team scale of 40k where you can differentiate between the guys in the squad, a demo specialist is one of the things marines can choose.

Why bother with any of that when you have rocket bullet guns and super duper armour?

Yeah I'd throw my 2 cents in and say this would be the jobs of the support unaugmented soldiery. I mean, don't get me wrong if a marine needed to he could toss a melta bomb at a bridge to drop it. Uriel Ventris did that sort of thing from time to time as the mission demanded.

Scouts have in various editions had some rules for stuff like mines, and sniper weapons have often been a major source of disruption, while they've had rules that favor cover, as far as things are represented in-game. They're also sometimes seen in various independent roles, while SW scouts are more specialists than regular Marines' versions/.

Particularly since they're not considered line troops that's what I'd say most qualifies.

 queen_annes_revenge wrote:
Why bother with any of that when you have rocket bullet guns and super duper armour?

Because also your enemies have rocket bullet guns and super duper armour.