EPA released their urban strategy for their Air Toxics Program, and they 
listed reciprocating engines as an area source they plan on regulated under 
the MACT regulations for formaldehyde. As you know, an area source is a 
location that emits less than 10 tons of any one Hazardous Air Pollutant 
(HAP) or 25 tons/year of all HAPs. This was a big surprise to industry. 

As expected they also listed oil and gas production as an area source they 
plan on regulating, but did not list transmission and storage dehydration, or 
turbines. They will regulate major sources for HAPs in all of these 
categories.

Marc