I've read several complaints about septic odors in basements and have learned very little from all of the responses. In my certain circumstance, I live in a brand new home (moved in the end of June '07) with a septic system. Everything was fine until the other day when I started smelling sewer gas in the basement (I've read cooler weather can cause this). The basement is finished and the kitchenette sink is the source of the odor. The main sewage drain goes out of the house about 4 feet away from the sink so this vent is the closest to the tank. My question is, is it possible for the gas from the tank to push past a p-trap? There is water in my trap and when I disconnected it I could feel (and smell) positive air pressure. Any help is appreciated.

Jivey