Hello, if I save right before trying to disarm a mine, but then a mine explodes during the disarm attempt, when I reload any of my recent previous saves (haven't tested older saves) the mines that blew up no longer exist in the world. Thanks! Great game as always.

if you close to main menu and load the save from there the mines won't be missing. It seems a game engine bug.

A game engine bug dating back to at least Oblivion. The game engine their using has always had numerous bugs in regards to loading save data during gameplay. The engine doesn't clear the entire game state, it only partially resets it and anything not explicitly mentioned in the save game file will use the old game state. Exploded a Mine? It will stay exploded because the save file doesn't store if a mine has not been exploded, it only records whether a mine is disabled or detonated. If you load the save game during gameplay it won't reset the mine because the save file doesn't say the status of the mine so the old engine state will be used.

For every Bethesda game it is strongly recommended to quit to the main menu before loading a Save Game to ensure the least buggy experience.