Raylo

We are getting ready to put in quartz countertops at my GF's place and she has one of those vents sticking out of the top of her sink that vents the garbage disposal near where the dishwasher drain line comes in. We'd like to do away with that if possible. My initial research indicates that it may be possible to do this IF the diswasher drain line has a check valve built into it.

As a reality check, my place just down the road does not have one of these vents. The dishwasher drain line is just plumbed directly into the disposal. My place is a bit newer and perhaps my DW has the check valve?

Are there any plumbers here who can advise?