I have almost an acre of land with 2 houses. I have been having a big problem with an odor-that was mostly coming from the front of my house(behind the Apt house). It smelled like a dead animal, but wasn't. Now the Apt house has the same smell inside! There is an old construction dump across the street that every now and then is used to dump tree stumps and concrete, and who knows what else! No one can pin point what this stench is! Any help would be greatly appreciated!

Methane is odorless. Perhaps you are smelling natural gas, methane with mercaptan odorant. Maybe they moved Jimmy Hoffa!

Also, sewer gas contains methane. Is there a septic tank involved? Back to you, Tom