I am installing a water softener in the basement of my home which was built in 2011. There is not any apparent drain location, and the sump pump is across a finished part of the basement so very difficult to access (and I don't really want to ruin the sump pump with salty water anyway). So, I appreciate guidance on the following option.
There is a 3" sewer cleanout sticking up out of the slab in the basement near where I want to put the softener, that is in-line between the basement powder room and the exit of the main stack to the city sewer. I was thinking of adding a 2" standpipe to this, and then have the water softener discharge line sit 1.5" above the standpipe to maintain the air gap. The standpipe would be connected to a p-trap, and then a studor vent before connecting to the 3" cleanout. I would also preserve the function of the cleanout using a san-tee.
Advice on this solution is appreciated!