This radon mitigation system was installed at a property I tested today. Shouldn’t the top of the pipe have a U-shaped or gooseneck anto it?
Thanks
Jonathan
Yes and it should also be above the roofline.
Does it have to go above the roof line if there are no windows or openings nearby?
I’m not 100% sure because I don’t do mitigation, but I believe so. Yes.
However, I did a radon test on a home that had a similar setup (garage side of the home). Radon levels were below 2.0 so apparently there was no negative effect.
What Mark said.
Yep.
Radon reduction systems must be clearly labeled. This will avoid accidental changes to the system which could disrupt its function.
The exhaust pipe(s) of soil suction systems must vent above the surface of the roof and 10 feet or more above the ground, and at least 10 feet away from windows, doors, or other openings that could allow the radon to reenter the house, if the exhaust pipe(s) do not vent at least 2 feet above these openings.
It must also have a “U-Tube”’ manometer installed on it also (not so you can look at U-Tube videos either…) 
This pipe did discharge at least 10 feet above grade. The house tested below 1.0. The house next door also had a mitigation system as well. The manometer and vent pipe on the interior of the property was clearly marked.
Thanks
Jonathan
In that case I would note it, tell the buyers about the “issue” but not make a big deal of it.