Photo from U.S. CSB animation.
For folks in West Virginia who have a new-found interest in chemical safety in the wake of the Elk River chemical spill, the latest report from the U.S. Chemical Safety Board is worth a read. Here’s part of the press release issued today by the CSB:
The April 2010 fatal explosion and fire at the Tesoro refinery in Anacortes, Washington was caused by damage to the heat exchanger, a mechanism known as “high temperature hydrogen attack” or HTHA, which severely cracked and weakened carbon steel tubing leading to a rupture, according to a CSB draft report released today. The draft report makes far-reaching recommendations to the federal Environmental Protection Agency and the Governor and State Legislature of the State of Washington to more rigorously protect workers and communities from potentially catastrophic chemical releases …
“Seven lives were tragically lost at the Tesoro refinery in 2010,” said Dr. Rafael Moure-Eraso, CSB chairperson. “I believe the draft report does an outstanding job of tracing this complex accident to its roots: a deficient refinery safety culture, weak industry standards for safeguarding equipment, and a regulatory system that too often emphasizes activities rather than outcomes. The report is a clarion call for refinery safety reform.”
Using sophisticated computer models, the investigation found the industry-wide method used to predict the risk of HTHA damage to be inaccurate, with equipment failures occurring under conditions the deemed to be safe from HTHA. It cited deficiencies in the company’s safety culture that led to a “complacent” attitude toward flammable leaks and occasional fires. Investigators also determined that during the unit startup, Tesoro did not correct the history of hazardous conditions or limit the number of people involved in the hazardous non-routine startup of the heat exchangers. But because of the reoccurring leaks and the need to manually open a series of long-winded valves that required over one hundred turns by hand to fully open, a supervisor requested five additional workers to help. All seven lost their lives as a result of the blast.
CSB Chairman Rafael Moure-Eraso said:
The accident at Tesoro could have been prevented had the company applied inherent safety principles and used HTHA resistant construction materials to prevent the heat exchanger cracking. This accident is very similar to the one that occurred at the Chevron refinery in Richmond, California in August 2012, where corrosion of piping went undetected for decades until it ruptured, endangering the lives of 19 workers caught in a vapor cloud and sending 15,000 community members to the hospital. Companies must do a better job of preventing refinery accidents, which occur all too frequently.
Regarding the U.S. EPA, the CSB report recommended:
Revise the Chemical Accident Prevention Provisions under 40 CFR Part 68 to require the documented use of inherently safer systems analysis and the hierarchy of controls to the greatest extent feasible in establishing safeguards for identified process hazards. Until this revision is in effect, develop guidance and enforce the use of inherently safer systems analysis and the hierarchy of controls to the greatest extent feasible in establishing safeguards for identified process hazards through the Clean Air Act’s General Duty Clause.
West Virginians may recall that the issue of industry not focusing on “inherently safer” designs and technology was discussed for many years regarding the former Union Carbide (now Bayer CropScience) plant in Institute and its now-dismantled stockpile of the deadly chemical methyl isocyanate, or MIC. And, we’re coming up on the two-year anniversary of a National Academy of Sciences report that noted the lack of focus by industry on the concept of inherently safer practices:
Key obstacles to their use include lack of familiarity with the tools among chemical process industry decision makers and the fear that the methods are either too simplistic or too costly to use … The use of these techniques could benefit not only the communities at risk from safety breaches, but also the industries themselves, as decision making techniques can help with the identification of profitable safety solutions that otherwise could be overlooked.