Objective 1: Infiltrate Main Compound
You'll start outside the enemy compound, don't go to the main gate as guards will sound the alarm when they see you (you don't want to mess with lots of bad guys at the start of the game). Instead go a little bit to the right from starting position where there is a gate with camera, shoot that cam w/ your silenced pistol before you get close. Picklock the gate (when you get close to the lock a key icon will appear) and go inside the building. There are just 3 guys here, so you can handle them one by one even with your pistol, or shoot the first guy and sneak past the other two (you can turn around the cargo containers and jump to the crates avoiding the 2nd guy and and the guard at the top walkway). Now go to the back door and head to the huge cargo containers.
Objective 2: Cross The River To Gain Access To Upper Compound
There's a space between the two cargo containers ahead of you (near the 2 big water tanks). Walk inside the gap so the guards to your right won't notice you. You'll notice the camera at the leg of the water tower in front of you, shoot it with your SD (pistol). On your map check the southern house with the two guards standing at the front. Go behind the house (don't run for they might hear you). Quietly kill them (or ignore them) and head to the factory (south of your map). While getting close you'll notice through the window a camera so shoot it before you enter. There are two guys here so you can kill them (sneak behind) easily. Get up the ladder (you'll know it when you see it) and before climbing the second ladder press the switch somewhere on your left (this will reverse the direction of the conveyor belt at the top).
After that climb again, but before jumping the conveyor belt use your binoculars and zoom forward, you'll notice a camera ahead, get your shooting skills ready and jump to the belt. This moves fast so you really should aim at the camera before it gets a closer look at your face.
**NOTE** Sometimes when I play this level even if I did not shoot the camera it doesn't notice me (the cam light will go red and blink but only once and the alarm will not sound) maybe the movement of the belt is fast and I arrived when the cam is rotating at the sides.
Objective 3: Activate, And Use Lift Down To Mines
Now we're inside the next factory building turn left until you reach the back door. Move quietly so the guard won't notice you then shoot him (take note of the camera stuck on the wall). Use your action key on the panel to open the door and head to the bunker. Use your thermal goggles so you can see the last two guys of this level. Before you get trigger happy check the camera at the left side of the wall. Shoot it first then finish the two guards. Now to get down you must activate the power by picking the gate lock and turning the generator on (it's near the camera to your left). Press the button on the wall near the generator (the one with the up arrow) then when the lift goes up, press the button on the other wall (the one with the down arrow) and stand on the lift to complete the mission.