LOS ANGELES (CN) — Federal prosecutors have sued Exxon Mobil to enforce compliance with subpoenas in the investigation of a 2015 explosion at its oil refinery in Southern California, which injured workers, destroyed property and released hazardous gases.
The United States asked the Federal Court on Tuesday to enforce compliance with subpoenas from the Chemical Safety and Hazard Investigation Board against Exxon Mobil Oil.
The February 2015 explosion and fire in Torrance released flammable hydrocarbons, “injured multiple workers and caused substantial property damage,” the government says in the complaint.
The blast came in a fluid catalytic cracking unit after exhaust particulates unevenly accumulated on expander turbine blades. The imbalance caused the turbine to shut down. Flammable fuels in a main column then flowed into a reactor, regenerator and electrostatic precipitator, where they ignited.
The explosion rocked surrounding areas with the force of a 1.7 magnitude earthquake, tore a hole in the side of the precipitator and sent ash filled with metals, fiberglass and glass wool into nearby neighborhoods.
So powerful was the explosion it catapulted a 40-ton piece of debris from the precipitator more than 100 feet. It landed 5 feet from a tank filled with thousands of gallons of modified hydrofluoric acid.
Hydrofluoric acid, a highly corrosive liquid that dissolves glass, can damage lung tissue and cause permanent blindness.
Blunders caused by Exxon’s weak safety standards continued, the government says in the 34-page petition to the court.
Company workers removing explosion debris in March 2015 improperly cut part of the precipitator, causing a fire that burned for several hours.
In September 2015, more than 5 pounds of modified hydrofluoric acid leaked from a pipe clamp and was released as a white vapor cloud.
Exxon installed the clamp to patch an aging pipe instead of replacing it, the government says.
The Chemical Safety and Hazard Investigation Board issued seven administrative subpoenas to Exxon, from June to October 2015, seeking evidence for its investigation.
Exxon officials did not fully comply with six of the requests, according to the complaint. It refused to produce risk assessments for an alkylation unit, plus ad hoc assessments for a fluid catalytic cracking unit and carbon monoxide boiler. In all, it ducked 13 of the 55 document requests.
“The United States has attempted to secure Exxon’s compliance with the board’s subpoenas through reasonable, good-faith negotiations,” the petition states. “These negotiations included numerous letters, phone calls, and in-person meetings between the board and Exxon and Exxon’s counsel.”
Regulators in 2016 approved Exxon’s request to restart the Torrance refinery, which was largely shut down after the explosion.
Non-party PBF Energy acquired the refinery last year. It is believed to supply 20 percent of the gasoline used in Southern California and 10 percent statewide.
Exxon officials could not immediately be reached for comment Wednesday.
PBF Energy vice president of corporate communications Michael Karlovich declined comment.
The Chemical Safety and Hazard Investigation Board, an independent agency, is charged with investigating major releases of hazardous pollutants and recommending measures to improve chemical safety.
In a separate case in April, a federal judge ordered Exxon Mobil to pay nearly $20 million for Clean Air Act violations at its massive petrochemical complex near Houston, Texas.
The penalty resolved a citizen’s suit filed by the Sierra Club and Environment Texas Citizen Lobby in 2010, which claimed Exxon released 10 million pounds of illegal air pollution from the plant from 2005 to 2013.