Have a septic tank system about 3 years old. Occasionally we notice a very strong sew smell on our back deck. It does seem to only occur when the wind is dead calm and temperature is very low just below freezing. There is a vent stack coming out the roof in the area with the strongest smell. It is also located on a lower portion of the roof near where the house has a next floor so stack is kind of in a closed in area where little wind would get to it to dispurse the smell. I am assuming what is happening is the warm air in the septic tank expands up the stack. Once in the cold air it cool and desends to the deck. Anyway to check out the source and what would be a possible correction to eliminate this smell?
email response not expected but to respond remove .uk at end TIA Hank