Wednesday, June 24, 2020

2020 Hurricane Season and Chemical Facility Safety – CSB and CCPS Insights


We are now less than a month into the official 2020 Hurricane season and we have already had four named storms. With both the official season forecast and recent updates indicating that we are looking at an active hurricane season this year, owners of chemical facilities near the Atlantic or Gulf coasts need to plan for protecting their facilities from potential wind, surge or flooding events associated with tropical systems. Both the Chemical Safety Board (CSB) and the Center for Chemical Process Safety (CCPS) recently produced guidance on what types of actions facility owners need to consider.

CSB Flood Video


No discussion of modern hurricanes and chemical facilities can take place without a brief discussion of the 2017 incident at the Arkema manufacturing facility in Crosby, TX during the aftermath of Hurricane Harvey. The CSB’s Arkema investigation page summarizes the incident:

“On August 29, 2017, flooding from Hurricane Harvey disabled the refrigeration system at the Arkema plant in Crosby, TX, which manufactures organic peroxides. The following day people within a 1.5 mile radius were evacuated. As the trailers increased in temperature the peroxides spontaneously combusted on August 31. Officials ignited the remaining trailers, on Sunday, September 3, 2017. The evacuation zone was lifted on September 4, 2017.”

Yesterday the CSB released a new video about the flooding risks at chemical facilities based upon the lessons learned in their Arkema investigation.

2020 Hurricane Season Guidance


Along with that flooding video, the CSB also published “2020 Hurricane Season: Guidance for Chemical Plants During Extreme Weather Events”. This brief document starts with the introduction of a new guidance document from CCPS (more about that below). It then continues with a discussion about actions that should be taken in restarting a chemical facility after a weather event. It has sections addressing:

• Hazards of startups following an extreme weather event,
• Relying on established safety systems, and
• Checking process equipment thoroughly.

That last section contains a brief checklist of items that need to be addressed. Includes a non-exhaustive list of details to look for when examining:

• Large bulk storage tanks for evidence of floating displacement or damage,
• Pressure vessels and small storage tanks for evidence of floating displacement or damage,
• Insulation systems for piping, vessels, and tanks,
• Sewers and drains,
• Furnace systems,
• Electric motors and drives, and
• Switchgear, conduit, electrical boxes, electronic and pneumatic instrumentation, emergency warning systems, emergency equipment.

CCPS Monograph


As mentioned in both the video and the CSB guidance, the Center for Chemical Process Safety (CCPS) has published a monograph on the “Assessment of and planning for Natural Hazards”. This document was prepared in response to one of the five recommendations from the CSB Arkema incident investigation. This is a much more detailed document (as one should expect) than the CSB guidance discussed above.

The 44-page document has sections on:

• Identifying natural hazards of concern,
• Gathering data about those hazards,
• Identifying equipment to be addressed in natural hazards assessments, and
• Evaluating against design criteria.

There are also two sections addressing post incident activities: recovery and recommissioning. As with most technically oriented documents, there is an extensive list of appendices providing more detailed information on topics such as:

• Site screening for natural hazards,
• Contents of a natural hazard’s emergency response plan,
• Activity list for before, during and after a natural hazard event, a
• List of interdependencies.

Commentary


The CCSP document has a wealth of good information, but there are two points that need to be repeated loudly and often. The first is a proper identification of the equipment that needs to be specifically covered in a natural hazard’s assessment. The document makes this important distinction (pg 2):

“For example, the emergency power system may be important for continued operation during a natural disaster, but the maintenance shop equipment may not be. Any equipment or operation that is required for safe operations or that, if compromised, could lead to a process safety event, harm to personnel the community, or the environment should be identified.”

The second refers to the failing at Arkema that was identified by the CSB accident investigation, ‘common mode failure’. The CCPS document explains (pg 3):

“A challenge in natural hazards response planning is that a number of important systems and pieces of equipment may be impacted by the same hazard at the same time, or in rapid succession. This may also include the layers of protection that have been installed to protect equipment. A common mode failure may be rising flood waters. For example, as the water level continues to rise, more and more equipment may be inundated and, eventually, even the equipment on “high ground” may also be flooded.”

Unfortunately, while identifying the ‘common failure mode’ problem, the authors do nothing to provide guidance on what needs to be done to ensure that those failure modes are adequately mitigated, or at least clearly identified in any subsequent risk assessment.

The other area where this CCPS document is light in its coverage is in their discussion of emergency response planning. The information in the two ERP appendices is very good for on-site emergency response planning. What is missing is discussion of pre-incident coordination with the local emergency response planning community. Only two topics (both important, to be sure) are identified:

Communications – “It is important that regional and national Emergency Service Providers be able to communicate with the facility Emergency Response Center and the facility being impacted by the natural disaster (if it is staffed).” Pg 21

Access Credentials – “Area access may be restricted before the disaster hits. Develop a plan for emergency access credentials for employees who will be coming in to staff the plant during the emergency. Do not count on employees being able to get in just because the disaster had not yet occurred. Local emergency officials may have already closed roads to all travelers without appropriate credentials.” Pg 23

What is missing is any discussion about coordination with the Local Emergency Planning Committee (LEPC) or other local/regional emergency planners about the specifically identified natural hazards for the facility and management plans for dealing with them. More importantly, identification of any mitigation assistance the facility might need as an incident progresses, or what off-site implications may need to be dealt with if facility plans fail to adequately contain a chemical incident.

One specific lesson from the Arkema incident is not addressed at all and that is the complication that lead to criminal charges being filed against the Arkema management. During the flooding event in Crosby, TX the road that led past the facility was the only major thorough fair that remained open during the flooding. Having to close that route because of potential chemical releases, caused so much problem for local authorities that they allowed emergency responders, without adequate training or equipment, to continue to use the road while the incident progressed.

An early discussion between facility management and local emergency response personnel should have identified this as an added problem for the facility that should probably have required a pre-flooding evacuation of the peroxides that caused the problems at the facility. Relying on just onsite consequence evaluations minimized the consideration of that option.

All in all, the two documents and video identified here are worthwhile and useful. Any chemical facility management team should review them closely and take appropriate action. Weather events are not going away and seem to be getting worse over time.

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