Entel level 1, turn left and run around building. Keep turning right at every
opportunity on around building and into an alcove in which there are 2
canteens and the outhouse. You are essentially spiraling inward. If you
haven't already, shoot the nearest fellow to the outhouse. You need that
dynamite! Shoot any others nearby so you can work undisturbed and retrieve the
dynamite. Save game here.

Go to outhouse and open door. Ignite and toss dynamite just in front of seat.
Anywhere else Might succeed but in front is the sweet spot. Panel blows off
exposing the green waste stream.
                                        
Hop in and follow to it's end and climb out. You are in a room with a large
gray disk. Circle disk to the door and open it. 2 grays are seen with a cow
suspended on a pole between them. Another gray's face appears and the door is
closed.

Return via waste stream to outhouse and climb out. Resume your quest to save
your daughter.

Nothing else seems to occur. No new powers or treasure as far as I can tell.
Just an amusing little side trip.