well...you probably just need a trigger multiple placed where you want "the mine" to be, then add 2 OnTouchStartAll outputs that enable the trigger_hurt and the env_explosion, then you need some OnEndTouchAll that disable the outputs once the person leaves (or dies) the trigger_multiple...
i have no idea how env_explosion works, but this should work for the trigger_hurt...just make sure you set the trigger_hurt to start disabled