Jet engine exhaust

We live approximatley 200 yards from a runway where 727, 737 and 747’s take off and land constantly. This is a facility where repairs are done on planes and engines. Also about 500 yards away there is a hanger where they detach the jet engines from the planes and bolt them onto a frame that is secured to the concrete floor so that they can run test on the engines at high rpm’s without having to fly the plane. The exhaust of these engines are directed straight at the front door of our home and the noise is very loud and you can actually smell the exhaust. Every three to four days all of the surfaces inside our home has a build up of a black oily substance. Its not dust. If you clean a particular surface in the home, in 3 to 4 days the same black oily substance will be there again on the same surface. I was wondering if anyone had an indepth knowledge of jet engines and their exhaust and If its possible that this black oily substance could be unburnt fuel additives comming through the eaxhaust. Because I’m aware of the fact that the aircraft industry puts additives in the fuel onboard in case of a crash this additive is suppose to help keep the fuel from exploding as much as it would without it. I suspect that if this additive won’t burn during a crash than it probably doesn’t burn when run through a jet engine and could be the cause of our problem at home.