GoldenEye 007/Dam

Neutralize all alarms (Secret Agent, 00 Agent)
There are 4 alarms on this level which must be destroyed.

Install covert modem (00 Agent)
The place to do this is right after opening the gate for the truck, and opening the fence/garage door. If you do the latter, you will reveal an enemy right before finding Ourumov (the man with a DD4 handgun). Walk around the outside of this room to the other side of the wall (behind the boxes) where you will see a computer. Push START and select the modem from your inventory and fire it onto the computer.

Intercept data backup (00 Agent)
Found underground after the area the covert modem is. Shoot the lock to open the fence and run along the damn to any of the buildings on the right side. Go in and under towards the direction you came from.

Cheats
Finish this level on Secret Agent in under 2:40 to get the Paintball cheat.