I'm adding a basement bathroom in my 1925 house in Minneapolis. I have some questions about covering an old floor drain and capping off a galvanized steel drain from the utility sink. Both drains connect to the main sewer line under the slab in places that I do not intend to excavate. I am at the point now where I have opened the floor and found my main cast iron sewer pipe buried six inches under the slab.

The floor drain is currenly right inside the door to the bathroom. There is a 1" deep slope down to the drain. The sloping area is 2' diameter so it is very much in the way and it is not needed since the shower drain will act as a the new floor drain. I want to plug this drain up and completely cover it and the slope with cement and the tile over it. I wonder what the best way to do this would be. I don't want whatever I plug it up with eventually working its way loose and pluging things up further down the line. I also don't want wet cement finding its way into the main sewer line.

The utility sink drain will no longer be needed and I'll need to cut it and cap it off under the slab. What is the best way to do this. Do I have to worry about sewer gas build up in either of these drains. The utility sink drain was hooked up to a secondary vent which will no be used for my new bathroom.

I have attached a picture below for clarification.

{{!gwi}}