Essentially, it could have come from any of the dozens of refineries along the Houston Ship Channel, or possibly from all of them.
On Tuesday ExxonMobil, the owner of one of the many refineries along the Houston Ship Channel, filed a regulatory report with the state environmental regulatory agency acknowledging that its Baytown refinery had been damaged during Hurricane Harvey.
The floating roof of one of the tanks at the refinery sank during the storm, unsealing the oil or other materials kept in the massive storage unit, which allowed particularly large amounts of emissions to escape the tank, including volatile organic compounds, chemicals that tend to morph into gases, some of which can have both short-term and long-term negative health effects, according to the federal Environmental Protection Agency.
The company also reportedly filed a report with the National Response Center disclosing that the Baytown refinery would release about 15 pounds of benzene, a known carcinogen, into the air.
This is all simply a part of doing business for Exxon and other refineries. (The Texas Commission for Environmental Quality has yet to respond to Houston Press questions about the mystery odor and the potential for leaks or emissions from area refineries and petrochemical plants during the storm, although a spokeswoman did veer off in an emailed response to talk about how the state environmental regulatory agency knows to expect leaks from wastewater plants during these kinds of weather events.)
While this disclosure does not necessarily mean that Exxon was the culprit or the lone culprit of the noxious odors that pervaded Manchester and other nearby neighborhoods during Harvey, it certainly helps explain why so many people reported catching whiffs of a metallic odor reminiscent of natural gas. After all, it appears almost everybody was flaring or just releasing all kinds of chemicals.
So far almost every major company with refineries on the Houston Ship Channel has filed notifications of air emission events with the TCEQ over the past few days.
In some cases the emissions are apparently the result of the shutdown processes the refineries went into when it became clear Harvey was going to strike this section of the Texas Gulf Coast. Chevron Phillips reported that it expected to exceed permitted limits for several hazardous pollutants, such as 1,3-butadiene, benzene and ethylene, during shutdown procedures. As we've reported, during shutdowns and startups, chemicals tend to be flared and released. Since the operations aren't up and running, it's much easier for hazardous materials to move out of these systems and into the air.
In other cases, it looks as if the sheer amount of rain dumped on Houston led to leaks. Valero's filing reported that the heavy rains from the storm caused "heavy rainfall complications" that allowed some of an unspecified product to leak onto the top of a floating roof and into the dike firewalls via the tank roof drains. The release? About seven pounds of benzene and more than 3,000 pounds of unspecified volatile organic compounds.
There are other reports along this line, and the odds are very high that more companies will be filing similar ones in the days to come as the refineries and plants deal with the fallout from shutdowns and get ready to restart their operations. (While 45 percent of the nation's refining capacity is located on the Gulf Coast, about a third of that capacity was in the path of the storm, so every minute that passes means there's less oil to feed the national appetite, as we've noted.)
In fact, you can count on more emissions from the refineries as the companies rush to get back to work and make up for the production time lost to Harvey. Governor Greg Abbott has suspended a slew of TCEQ rules governing everything from air emissions to how companies deal with spills and waste. EPA Administrator Scott Pruitt has already signed off on another Clean Air Act waiver on certain fuel requirements for the Texas oil industry to make it easier to pump out fuel, which means the refineries can cut a few corners with the full blessing of federal environmental regulators without having to worry quite so much about what gets spewed into the air.