Statement by Professor
Jerry Havens
Oral Hearing on the
proposed LNG terminal in County Kerry, Ireland
January 23, 2008
My name is Jerry Havens. I am a
Professor of Chemical Engineering at the University of Arkansas in
the United States. I am speaking here as a concerned scientist; my
comments are not to be attributed in any way to the University of
Arkansas. Thank you for allowing me to appear here on behalf of the
Kilcolgan Residents Association (KRA).
As I understand why you might question
the propriety of my “butting in” on this LNG terminal siting
hearing, I hope you will give me a few minutes to explain my purpose.
I have spent my adult life researching
the potential consequences of catastrophic releases of hazardous
materials, with emphasis on fire and explosion hazards. I submit to
you my resume, which gives more detail than I have time for here. I
think it pertinent, and hopefully of interest to you, to state that I
have had a close association with European authorities on such
questions as the one before this authority since the late 1970’s,
having first served in England as a consultant to the Major Hazards
Committee and the Health and Safety Executive in the conduct of the
heavy gas trials at Thorney Island in Hampshire in the early 1980’s.
The Thorney Island trials were gas dispersion experiments which were
recommended by the British Government as the result of the
Flixborough disaster of 1974, in which there occurred a very serious
explosion of a cyclohexane vapor cloud that resulted in worldwide
changes in regulatory practices for handling of hazardous materials.
Similarly, I investigated, and continue to study, the Bhopal gas
cloud disaster which occurred in India in 1984, arguably the worst
industrial chemical accident in history. I was invited to
participate in research resulting from these catastrophic events, as
well as other similarly directed programs in Europe largely because I
was contracted by the U.S. Coast Guard in the late 1970’s to
develop a general purpose gas dispersion model that would be
particularly applicable to LNG vapor dispersion, a subject that was
of great interest in the 1970’s, as now. I played a seminal role
in the development of the two LNG vapor dispersion mathematical
models currently required in the United States to be used by
applicants for approval of LNG terminal sites. I have also been
heavily involved in the development of the mathematical models that
must be used to determine the fire radiation safety distances that
must be observed for approval of LNG terminal sites.
In the U.S., presently, approval of
land-based (as opposed to offshore) import terminal sites is the
purview of the Federal Energy Regulatory Commission (FERC), whereas
the U.S. Coast Guard currently plays the more formative role
regarding the safety aspects of the shipping side of the project. I
have most recently been heavily involved in continuing studies to
better determine the potential consequences of marine incidents
involving LNG – with emphasis on studies of the consequences of
very large vapor clouds or pool fires that could result from massive
spillage of LNG onto water.
I believe that there is sufficient
similarity in the LNG terminal proposals under consideration that
similar requirements for the protection of public safety are
appropriate worldwide. These ventures, which involve the potential
for very high consequence accidents or intentional events, are truly
international and should be treated with a high degree of care and
cooperation – it is in everyone’s best interest to be as certain
as practicable that we treat these issues with the respect they
deserve.
I want to state before proceeding that
I am neither for or against any particular LNG terminal on any other
grounds than provision of public safety – that is the only
expertise I am professing here - which brings me to why I agreed to
appear at this hearing to speak on several issues that I believe are
important for you to consider in the process of siting LNG import
terminals.
Potential Consequences of LNG
Releases from the Terminal
For the land based part of an LNG
terminal, I believe that our current understanding of the
consequences of releases on land, where they can be most effectively
contained, is sufficient in large measure - needing for the most part
only “maintenance” efforts to insure the propriety of that
information to changing industrial practices. I am not here to
suggest that we drastically need more study in this area - I am
suggesting that the information that has been made available in the
research programs already completed is not being brought uniformly on
board in the siting process. I point to perhaps the most glaring
example that I have observed in the discussions relative to the
Shannon LNG terminal proposal. In discussions relative thereto, I
have read, and heard expressed at large, the opinion that LNG vapor,
being principally methane, is lighter than air and therefore will
rise harmlessly into the air (if LNG is spilled) – out of danger.
It is true that methane vapor at ambient temperature is lighter than
air, providing an important and widely recognized safety feature of
natural gas in contrast to heavier-than-air fuel gases such as
propane or butane (or cyclohexane, as at Flixborough). But LNG is a
liquid at very low temperature, about -165 oC, and the
vapor initially formed from LNG is at that temperature also, and
because of its low temperature, it is considerably heavier than air
(about � again as heavy). The result is that an LNG vapor cloud
will spread laterally and remain close to the ground, prolonging both
in distance and time the potential hazard to the facility and to the
public. That hazard is primarily a fire hazard, rather than an
explosion hazard, for reasons which I will be happy to explain but
think I should not go on about here for want of more important
things. So, one of the principal concerns that I want to highlight
here is that in haste to site LNG terminals we should be careful not
to cut corners on issues of public safety such as this glaring
example implies.
Potential Consequences of LNG
Releases from LNG Ships
The shipping side of the LNG
importation business is more complicated, in my opinion, if only
because the major emphasis on regulatory requirements for public
safety have historically been associated with the land-based part of
the ventures. In the United States, there are mandatory “exclusion
zones” required for the land based terminals; these exclusion zones
demarcating zones in which the public is not allowed. However, there
are no such mandatory zones (as opposed to “safety/security zones”
which are required by the Coast Guard during passage to or from, or
at the terminal) to exclude the public from the vicinity of LNG
ships. I believe that more serious consideration should be given to
this gap in the provision of public safety measures relating to
potential ship release incidents. The containment vessels (cargo
tanks) on LNG carriers are, because of weight requirements primarily,
likely to be more vulnerable to failure due to puncture damage,
especially if intentional, than the more massive land-based “full
containment” storage tanks currently in favor. And, whereas spills
from a land-based tank are required to have secondary containment
features to limit spreading of the spilled LNG, no such measures
appear to be practical for spills on water. The result is that if a
large spill occurs from a ship onto the water, it will spread until
it completely evaporates, whether burning or not. If ignition does
not occur, a vapor cloud forms which can drift significant distances
with the wind before it becomes diluted to a concentration where it
cannot be ignited. During that travel, if the cloud is ignited the
result is a vapor or flash fire which will severely endanger people
or property caught in the confines of the fire. LNG is not odorized;
unlike natural gas that leaks in your house or from a pipeline, which
is required to be odorized, you cannot smell it. If ignition does
occur the result is a pool fire, basically similar to any other fire
that results when liquid fuel is spilled on water and ignited. Large
LNG fires on water have not occurred throughout the fifty to sixty
years that LNG has been shipped on water. While that record is
justifiably encouraging, we must not encourage, or allow,
corner-cutting here either, in taking adequate and appropriate
measures to protect public safety.
Rationally Assessing the Risks
The KRA asked me to respond to the
“Prime Time” video presentation by Dr. Tony Cox regarding the
Shannon LNG terminal proposal, and I agreed to do so. Dr. Cox and I
worked together in the 1970’s and 1980’s in the various research
efforts designed to get a better understanding of the potential for
“dense gas” behavior of LNG vapor evolved from spills. The video
presentation by Dr. Cox appears to be in essential agreement with me,
as described above, regarding the interpretation of dense gas
behavior by LNG vapor clouds.
However, at the close of the video, Dr.
Cox stated: “The risk is in fact extremely low - and any rational
person or any person who is fully informed ought to be able to accept
them and I would.” As I stated earlier, I have had a long
association with Dr. Cox, which I hope to continue. But I am puzzled
by his statement. I intend to talk with him about this issue to get
clarification of his view, as I am fully aware of the difficulty of
expressing one’s full thoughts under the pressure of media
scrutiny, but I have been unable to do so in the very short time
since agreeing to be here today. So, I will try to tell you why I am
concerned about his statement, and hope that he will be willing to
set me straight if I have misinterpreted anything he said. Perhaps
it is simply in the end a disagreement between us – but I think it
is important that experts be prepared to defend their statements and
I expect that Dr. Cox would agree.
I agree with Dr. Cox that the risk is
low. But I believe to say that it is extremely low, which well might
be interpreted by the public as justifying dismissal from further
careful consideration, is not justified. I also agree with Dr.
Cox’s assertion that there is no such thing as a risk free
activity. That is why I believe that in our increasingly
technology-based society, which is likely to continue as long as we
can maintain it, we have to balance the risk (probability) and the
consequences in order to determine the acceptability of a venture
such as LNG importation. However, adequately and quantitatively
balancing risks and consequences is not easily accomplished -
certainly not by just making subjective statements such as “extremely
unlikely”. Furthermore, even if the feared events are determined
to be extremely unlikely, if the consequences of the event could be
so severe as to raise serious questions as to the acceptability of
the venture anyway, there may justifiably remain serious concerns.
That is the quandary we are in today
with such ventures as LNG importation. As with the continuing
difficulty in arriving at a measure of acceptability of risks that
plagues the nuclear industry, the chemical/energy industry has
developed a major consequence hazard identification.
As an example of the confusion that
reigns in this area, I have heard repeatedly expressed that the
energy content of an LNG ship is equivalent to that of 50 or more
Hiroshima-yield nuclear weapons. In my opinion that is an
unjustified stretch. However, the statement that the energy content
of an LNG ship is that large is entirely true; the comparison however
is meaningless unless the time in which the energy can be released
(fraction of a second in a weapon; much longer in the case of an LNG
fire involving the entire contents of the tanker) is considered.
Nevertheless, the potential for catastrophic consequences to result
from large releases of LNG, especially onto water, where spreading
and rapid evaporation could not be controlled, cannot be dismissed.
It is for these reasons that I believe the potential consequences of
catastrophic failures of LNG ships should be more carefully
considered.
The LNG shipping industry, as is
clearly the case with the entire LNG industry, has an enviable
record, of which I think they should be proud. However, this is
surely not a time for complacency, or cutting corners. I believe
that serious consideration should be given to recommendations to the
United States Congress by the Government Accounting Office (MARITIME
SECURITY – Public Safety Consequences of a Terrorist Attack on a
Tanker Carrying Liquefied Natural Gas Need Clarification ,
GAO-07-316, February 2007) to determine the potential for
cascading failures of the LNG containments (tanks). The GAO has
called the cascading failure issue the leading unaddressed priority
need for LNG safety research associated with LNG shipping.
If an LNGC were to be attacked in the
proximity of the shoreline, either while docked at the terminal or in
passage in or out of the estuary, and cascading failures of the
ship’s containments were to occur, it could result in a pool fire
on water with magnitude beyond anything that has been experienced to
my knowledge, and in my opinion could have the potential to put
people in harm’s way to a distance of approximately three miles
from the ship. I have testified repeatedly that I believe that the
parties that live in areas where this threat could affect them
deserve to have a rational, science-based determination made of the
potential for such occurrences, no matter how unlikely they may be
considered.
In closing I want to say that the
Kilgogan Resident’s Association assured me in requesting my
presence here today that their main concern “has been and remains
the safety aspects of the Shannon LNG project and the idea of having
to live with the thought of an accident, however remote, for the next
number of decades.” They have assured me that they are not against
LNG, and that they have endeavored only to highlight any shortcomings
for completeness in the quest to insure public safety to the maximum
extent practicable. Finally they have assured me that they have
attempted to be pragmatic in the consideration of what will
ultimately be required tradeoffs of the environment with the economy.
It is because I agree completely with
these sentiments, and because I want only to ensure to the maximum
extent possible that we site LNG terminals, as should be the case for
any other major hazards industry venture, in full view and
observation of the best scientific knowledge and guidance available,
that I happily agreed to appear here today.
Thank you,
Jerry Havens
Distinguished Professor of Chemical
Engineering
University of Arkansas, USA
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