benzene
agreed that the concentration of nasty fumes in the air around the fueling hole of a car is unhealthy; however, houses and publicly accessible ground is typically at least 10s and usually 100s of feet from gas wells. During drilling it's usually much more than that. Dissipation is a function of r^2.x (x>0) so the concentration drops off rapidly away from the source. If the concentration and effluent rate is so high that it doesn't dilute to a sufficiently low concentration over a small radial distance, then it not only is a breathing hazard to the operating personnel, but it's also a fire hazard. Since both of those are deletarious to profitable operation well operators have an incentive to not let those things occur. In addition, if a well is losing benzene, then it is also leaking larger quantities of methane, ethane, and propane, etc. which are profit (and liability).
Gas wells do leak. That's a fact of life. However, I'd bet that the concentration of benzene within 5 feet of any normally operating well (i.e. one that is not in iminent need of repair) is much less than the concentration of benzene within 5 feet of an operating gasoline station pump. Taking into account the relative amounts of material being delivered to the surface from the 2 sources I'd say gas wells perform remarkably well.
Maybe the Fort Worth official should move to La Brea.
cheers,
Charlie
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