I am remodeling my kitchen and would like to install the sink and dishwasher in an island. The sink is currently drained and vented on a single pipe that is separate from any other plumbing in the house. I am wondering if I can cut the pipe and remove the upper portion (ie the vent) and drain my sink and dishwasher into the bottom half using an AAV for a vent. This would mean that there is no actual vent on this part of the system that would go through the roof. Thanks in advance.