Chevron Refinery Charged For 'Rotten Egg' Smell

EL SEGUNDO, CA — The South Coast Air Quality Management District has issued a notice of violation to the Chevron Refinery in El Segundo for a recent hydrogen sulfide release that resulted in "odors impacting the public," the agency announced Thursday.

The notice of violation alleges that the refinery caused a public nuisance in violation of the AQMD's Rule 402 and California Health and Safety Code Section 41700.

Once issued, a notice of violation can result in civil penalties. In some cases, the company can choose to implement voluntary measures to reduce emissions or otherwise prevent further violations. If no settlement is reached, a civil lawsuit may ultimately be filed.

A spokesman for the refinery could not immediately be reached by phone early Thursday afternoon.

On Jan. 31, the South Coast AQMD received more than 30 public complaints of "rotten egg- and sulfur-type odors," the agency said in a statement.

"Inspectors confirmed that the odors were coming from the refinery," the agency said. "Inspectors determined that the odors were caused by the release of hydrogen sulfide during the transfer of petroleum naphtha — a product of refining crude oil — to a storage tank."
The odors had dissipated by late afternoon.

At the time the odors were reported, Chevron's "fenceline" monitors showed several instances when hydrogen sulfide levels exceeded the short-term, state standard of 30 parts per billion, with the highest one-hour average being 168.7 ppb at 10:20 a.m. on Jan. 31, the agency said.

Data from the nearby community monitors in El Segundo and in Manhattan Beach showed that levels remained below 2 parts per billion during the same time period, however, the agency reported.

"As part of South Coast AQMD's Refinery and Community Air Monitoring Program -- Rule 1180 -- real-time air monitoring is required for a variety of toxic air pollutants at the fenceline and in nearby communities of major refineries," the agency said.

Hydrogen sulfide is a gas that occurs naturally in crude petroleum and is known to have a rotten egg smell. Short-term exposure to this type of odor can cause people to experience health symptoms such as headaches and nausea.

Staying indoors with doors and windows closed during odor events would help reduce these health impacts. Symptoms typically go away soon after the odors are no longer detected.

Chevron's air monitoring network information can be found here. The community air monitoring information can be found here.

South Coast AQMD is the air pollution control agency for major portions of Los Angeles, Orange, San Bernardino and Riverside counties, including the Coachella Valley.

— City News Service contributed to this report.