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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