Discussion Central

Expand all | Collapse all

CSB Report on Reactive Chemical Incident

  • 1.  CSB Report on Reactive Chemical Incident

    Posted 12-17-2019 19:20
    The CSB published its report on the 2017 tank explosions at the Midland Resource Recovery facility in Philippi, West Virginia. Two separate tank explosions occurred, killing three workers.

    Midland Resource Recovery cleaned natural gas odorizer equipment before disposal to remove the mercaptan odor. They cleaned the equipment by treating the equipment with sodium hypochlorite. The CSB hypothesizes that Midland Resource Recovery had unintentionally reacted chemicals in the odorizer equipment to produce alkyl hypochlorites, which are thermally unstable and highly explosive. 

    The CSB found that there was not an effective safety management system in place to identify and control hazards from reactive chemicals. Among other things, MRR had no formal hazard identification process in place to analyze or characterize what chemicals were inside the odorizer vessels-and in what quantity-before decommissioning and chemically treating this equipment with sodium hypochlorite. The company also lacked effective safeguards to prevent unexpected or uncontrolled chemical reactions.

    The CSB provides the following key lessons for companies that deal with reactive chemistry:

    1. Companies need a robust safety management system in place to prevent reactive chemical incidents. If a process has the potential for uncontrolled chemical reactions to occur, the company should conduct a formal evaluation of the reactive chemistry, perform a hazard analysis, and ensure that sufficient safeguards are in place to prevent reactive chemical incidents.

    2. Companies should have a thorough and complete understanding of their reactive chemistry under design conditions and under all foreseeable abnormal conditions. For example, companies should avoid treating uncharacterized waste materials with sodium hypochlorite because of the potential explosive hazards associated with its complex reactive chemistry.

    The investigation report can be accessed at this link: https://www.csb.gov/midland-resource-recovery-explosion-/

    Lauren Grim, PE,CFEI
    Supervisory Chemical Incident Investigator
    U.S. Chemical Safety Board
    Denver, CO

  • 2.  RE: CSB Report on Reactive Chemical Incident

    Posted 12-19-2019 19:42
    Background for a general reply: when I read to "West Virginia" the politics of the State's elected government and the common stereotypes, even canards, want to force themselves on me as the quick and dirty explanation and reason for this disaster.

    I am still fighting them off and will not comment on the incident or report yet.

    Thank you.

  • 3.  RE: CSB Report on Reactive Chemical Incident

    Posted 12-20-2019 00:23
    Edited by Steve Cutchen 12-20-2019 00:24
    Keith, I'd love to hear more about your issues. I'm not sure I understand.

    I can see a couple of possible interpretations of your points;
    1) the State is being rather simplistic in their causal analysis and missing the significant points, or
    2) the State is attempting to color the causal analysis in order to direct blame.

    Or maybe it's something else.

    What is most important to me is the clear, unbiased, fact-based non-blaming analysis of why these types of incidents occur. I'd love to understand more about what sounds like your concerns that this type of analysis is not being made.

    Steve Cutchen
    Houston TX

  • 4.  RE: CSB Report on Reactive Chemical Incident

    Posted 12-20-2019 07:22
    I do not accuse the State right now of any misconduct. I can tell I am defaulting to stereotypes before even reading the report, which is a mental misconduct. I certainly do not either accuse the CSB of anything before even reading their work or devalue the need of an independent-as-possible entity with the power and capability to perform comprehensive and authoritative reports for all.

  • 5.  RE: CSB Report on Reactive Chemical Incident

    Posted 12-22-2019 12:49
    As a side note, the petroleum refining industry, has two old RSH treating technologies that could be considered for the original vessel cleaning.  The first uses a dilute aqueous mixture of copper chloride to oxidize the RSH.  The second uses dilute NaOH to oxidize the RSH (2RSH + 2 NaOH → 2NaSR + 2 H2O).   The second method is still used in today's refineries, via UOP's Merox process and Merichem's proprietary caustic treating process.  Of course, the presence of any aluminum internals presents a very dangerous problem as NaOH would react with the Al to potentially produce hydrogen and CuCl2 is also reactive with Al (3CuCl2 + 2Al => 2AlCl3 + 3Cu).  The original CSB report highlights the extreme dangers of an inadequate reactive chemical review. 

    The CSB report also highlights that a second death occurred about 1 month after the initial incident that killed the first 2 people.  It should have been noted that in the original post that the CSB was onsite and simply objected to the second vessel cleaning incident.

    Paul Stobbe
    Pearland TX

  • 6.  RE: CSB Report on Reactive Chemical Incident

    Posted 12-23-2019 19:03
    Yes, CSB investigators were onsite at the time of the second explosion.

    CSB had arrived at MRR to conduct interviews as part of the investigation. When the investigators arrived, MRR counsel informed the CSB that MRR would drain the other odorizer equipment that contained the sodium hypochlorite cleaning solution. This work would be done by their contractor hired to perform an investigation of the first incident and mitigation work.  The CSB was highly concerned about this plan, as the cause of the first explosion was not yet fully understood and the CSB was concerned that the other equipment could similarly explode.

    MRR's contractor had been hired through MRR's legal counsel, and MRR asserted attorney work product over all work the contractor performed. As such, MRR blocked CSB's attempts to speak with the contractor on the wisdom of the plan to drain the equipment without fully understanding the first incident.

    Shortly after the contractor began draining the first odorizer--to the objection of CSB--it exploded, killing a worker. During the operation, CSB investigators had taken shelter behind a structure about 150 feet away.

    Lauren Grim, PE,CFEI
    Supervisory Chemical Incident Investigator
    U.S. Chemical Safety Board
    Denver, CO

  • 7.  RE: CSB Report on Reactive Chemical Incident

    Posted 12-23-2019 19:04
    The story about the 3rd death caused by the 2nd explosion will take your breath away.  See Section 4.2 of the report that starts on page 21:  https://www.csb.gov/file.aspx?DocumentId=6121  The second explosion was 35 days after the first.  

    I hope that what happened that day in June winds up in engineering ethics curriculum.  Clearly, there were ethical violations, but were any ethical violations committed by CSB?  It's my understanding that CSB didn't have the authority to do more than object on the day of the second explosion, which they did.  Is there a way they could have stopped that second explosion from happening?


    Kirsten Rosselot
    Process Profiles
    Calabasas, CA United States

  • 8.  RE: CSB Report on Reactive Chemical Incident

    Posted 12-24-2019 10:25

    All the CSB could do is object or leave the site if they felt it was unsafe to be there. 

    The CSB is an independent federal agency charged with investigating industrial chemical accidents. The agency does not issue fines or citations, but does make recommendations to plants, regulatory agencies such as the Occupational Safety and Health Administration (OSHA) and the Environmental Protection Agency (EPA), industry organizations, and labor groups. Congress designed the CSB to be non-regulatory and independent of other agencies so that its investigations might, where appropriate, review the effectiveness of regulations and regulatory enforcement.

    James Wesnor
    Senior Technical Advisor
    Birmingham AL

  • 9.  RE: CSB Report on Reactive Chemical Incident

    Posted 12-26-2019 13:01

    A few more comments on the MRR incident. 

    Given the differing and complex views on the chemistry involved in the explosion, the CSB recommendation to evaluate the reactive hazards could prove to be an insurmountable task. 

    Another approach, besides not using dilute bleach, might be to vent the vessels to the atmosphere while circulating and filling the vessels to be cleaned.  Each vessel should be vented separately.  The vent would have to go to a scrubber or flare or both to prevent any toxic materials from being released to the atmosphere.

    Further keeping the vessels liquid full (with mostly water as described on page 14 of this CSB report) would potentially to reduce the risk of any alkyl hypochlorites from forming?  Certainly, not being liquid full increases the risk for trouble.  Proper venting would help insure that the vessels are liquid full.

    I don't agree with the use of a pressure safety valve (PSV) as recommended by the CSB on page 33.  The PSV would not prevent the pressure vessel destruction from the as described explosion.

    And most significantly, given the extreme adversarial relationship that developed between the CSB and MRR and the CSB and DuPont (as described in this CSB report), alternatives must be provided to remove these adversarial relationships.  One such remedy would be for the CSB to recommend to Congress that any company or individual that cooperates with the CSB would be given complete immunity from any criminal or civil prosecution.

    Paul Stobbe
    Pearland TX

  • 10.  RE: CSB Report on Reactive Chemical Incident

    Posted 12-26-2019 19:16
    From outside these 3 entitys, I have to ask, is the industry view that CSB are insolent or otherwise unprofessional? My reading "between the lines" of this report (the MRR one) is they got shown up (privately, before this was published) for being unable to answer some highly important questions about their work (what are the concrete blocks for?) and not being able to prove what they claimed when asked for it (documenting process stage on paper as well as spraypaint).

    That is hard to swallow for any one, but some take it the right way and others don't. If any one can confirm or correct this view without violating privacy, please tell me so I do not blame any one unjustly.

  • 11.  RE: CSB Report on Reactive Chemical Incident

    Posted 01-07-2020 08:11
    This incident does highlight a challenge in regards to the CSB not having the enforcement role / power to prevent the second fatal accident at MRR.  With MRR citing confidential work product and refusing to divulge details to the CSB between the first and second accident, and the CSB being unable to speak with the contractor performing the work on the second vessel and unable to do more (enforcement-wise) than object to the plan for the work on the second vessel, it seems that the CSB had limited options / power to prevent what was clearly an avoidable fatal accident.  Of course, the ultimate accountability is with MRR, as well as some responsibility with the contractor performing the work (who should have known about the first fatal accident and should have ensured that it had sufficient information to perform the subsequent work safely).  

    This example certainly indicates that there is opportunity for improvement.  However, I would have concerns about offering immunity from criminal or civil prosecution in exchange for collaboration with the CSB.  ("One such remedy would be for the CSB to recommend to Congress that any company or individual that cooperates with the CSB would be given complete immunity from any criminal or civil prosecution.")  Viewed pessimistically, what would prevent a firm from knowingly acting in ways that were unsafe (for the sake of time, money, ease, etc.), knowing that they could be safe from legal repercussions as long as they cooperated with the CSB after the fact?  

    Andrew Riederer
    Quality Operations Manager
    Boehringer Ingelheim
    Columbus OH

  • 12.  RE: CSB Report on Reactive Chemical Incident

    Posted 01-07-2020 10:47
    The CSB is patterned after the National Transportation Safety Board, and like the NTSB is by design an independent scientific agency with no regulatory or enforcement function and no alignment with any other governmental department or agency. This independence is critical to their work both because federal regulatory agencies are often the subject of their recommendations and because this scientific basis allows for better investigative cooperation. An effect of this is that the CSB cannot require that its recommendations be adopted. Adoption depends on the strength of the scientific and rhetorical basis of the recommendations themselves.

    Steve Cutchen
    Investigator, retired
    US Chemical Safety Board
    Houston TX

  • 13.  RE: CSB Report on Reactive Chemical Incident

    Posted 01-09-2020 18:51
    If that was taken up by Congress, I'm sure they would include some "good faith" requirement to defeat that purpose. From a distance, could they (Congress) legislate so CSB can work closer with an existing enforcement arm like OSHA?