areas when doing this but flight safety is paramount so if it has to be done it has to be done (sort of when you gotta go you gotta go). Fortunately the higher the altitude the more it disperses but in the instance of the 777 that blew the engine over Broomfield the crew decided the situation called for getting back to the airfield ASAP was the most prudent thing to do. I did not hear if they dumped fuel or not but if they did it could have been an environmental concern at the altitude they were at calling for clean up measures.