Cetacean Society International
Action Alerts and Updates on Current Issues
Respond To The Low Frequency Active Sonar Draft Environmental Impact
Statement
Public Comment Period Closing 28 October 1999
Please use your one opportunity to comment on the U.S. Navy's Low Frequency
Active Sonar Draft Environmental Impact Statement before the public comment
period closes 28 October. CSI has participated directly since 1996, tried to be
objective and open minded, and we have given the Navy the benefit of the doubt
again and again. We have spent a great deal of effort trying to understand and
communicate this very confusing and complex issue. Frankly, it scares us. It
should scare you too.
The LFA is a complex system designed to locate the super-quiet submarines
that older sonars can't find. Many military professionals consider the system to
be of little practical use. To start with, it's very vulnerable. While
announcing itself to anything within hundreds of miles it can only work at 3
knots, and it can't turn easily while transmitting. Below are several points
that we think illustrate the flaws in the LFA DEIS. You might consider including
some of them in your own comment, in you own words. Below those points is the
technical, supporting background. For more details, and the history of the
controversy, please review "Whales Alive!" newsletters archived on this website
starting in October, 1996.
Please send your comments to:
Mr. J. S. Johnson
Attn: SURTASS LFA Sonar OEIS/EIS Program Manager
901
North Stuart Street, Suite 708
Arlington, VA 22203
Fax: 703-465-8420.
(Emails are not acceptable)
- Because the LFA has the potential to do harm to the marine environment,
because it is so loud that it can kill, all operations should be based on
conservative levels of sound. Instead, but with considerable lip service to
being conservative, the DEIS downplays the risks and asserts that the LFA is
safe to operate. This DEIS assertion rests on insufficient evidence and
supports itself with self-generated figures and graphs. Demand that scientists
not associated with the LFA review the assertions before they are considered
valid.
- A received level of 180 dB is far too loud to be considered the beginning
of a precautionary zone around the LFA. Most experts consider that level
damaging, and urge caution with sounds far quieter. Demand to know the facts
and experts' opinions the Navy implies support a level of 180 dB as the start
of mitigations.
- There is no "ramping up" of the LFA sounds to allow close animals to move
away. This procedure is demanded for many other loud sources to operate.
- Cumulative noises multiply the negative impacts of single sounds. The Navy
asserts that they need not extend the mitigation zone to account for the
cumulative effect. By their own figures, 100 LFA transmissions shift the
mitigation point from 180 dB to 170 dB, which could be several miles from the
source depending on conditions.
- For their mitigations of the LFA's dangers the Navy relies on detecting
vulnerable marine life within 1 kilometer. They assert that they can detect
sea turtles and dolphins 1 kilometer away from the LFA even at night and in
any weather. They rely largely on a fish-finding sonar that has not been
tested, and assert that it won't affect bow riding dolphins.
- All deep-diving toothed whales are ignored. There was no directed
research, but there is considerable scientific evidence that toothed whales
may be very vulnerable to LFA sounds. The sperm whale is ignored because there
are enough of them that harming some won't affect the population.
- All effects of the LFA on the behavior of marine animals are ignored.
Communication, reproduction, and feeding and avoiding predators are not
"biologically significant" unless whole populations are at risk.
- The Precautionary Principle is a basic scientific rule that, in the face
of ignorance about our effects, we must move carefully and cautiously. The
DEIS ignores this Principle, in spite of warnings by most scientists that
human don't know enough about the effects of our noises in the oceans. The LFA
DEIS discusses the need to be cautious and conservative but all actions are
based on unrealistic and aggressive assumptions about the LFA's effects below
180 dB. In practice everything outside of 1 kilometer is simply ignored.
- The Scientific Research Program (SRP) assumed to support the LFA DEIS is
inadequate and asserts unsubstantiated conclusions. Given the SRP data
presented, would a reasonable and objective expert reach the same conclusions?
Based on the flawed SRP results the DEIS demands that all previous research
urging caution be put aside in favor of some unsubstantiated or stretched
conclusions.
Background
Why has CSI been so focused on the LFA? First, and most disconcerting, there
is much more at stake than just this one sound source. NMFS has failed to
establish specific definitions of human noise impacts that would allow
management strategies and regulations to be implemented. By default the LFA DEIS
may be used for this purpose because of its scope and timing. Senseless as it
seems, future regulations written to manage all harmful human noise in the ocean
may be defined by a military contractor intent on selling a very loud product.
Foxes should not be allowed to guard hen houses. To their credit NMFS has tried
several times to get expert and specific definitions. When pressed the experts
only agreed that we are all too ignorant of anthropogenic acoustical impacts to
declare specific numbers. As one result the DEIS has used the highest numbers
they can find to define the LFA's lowest mitigation threshold, and dismisses
most caveats declaring ignorance and demanding caution.
CSI's second concern with the DEIS is that it has the potential to do harm to
the marine environment; the LFA is so loud that it can kill. Third, in spite of
intuitive reasoning, there are so many unknowns about the significance of human
noise in the oceans that any major source of objective data has enormous value.
We therefore had high hopes for the associated Scientific Research Program (SRP)
funded by the Navy to quantify human noise impacts on cetaceans. In retrospect
it didn't. Fourth, all the panels of experts convened by NMFS have made
recommendations that are highly equivocal, laced with statements about unknown
hearing threshold levels and ultimate effects of noise. They consistently argued
for extreme caution in the face of ignorance. This is the Precautionary
Principle, and it is missing altogether in the DEIS.
"The Draft Overseas Environmental Impact Statement and Environmental Impact
Statement for Surveillance Towed Array Sensor System Low Frequency Active
(SURTASS LFA) Sonar, Department of the Navy, Chief of Naval Operations, July
1999" is a lengthy, repetitive, assertive, unsubstantiated, misleading document.
It purports to satisfy the legal requirements to enable the LFA to become
operational, and that assertion will follow it to court. Over and over it says
that "...no non-serious injuries are expected to occur and any taking would be
infrequent, unavoidable, or accidental. The numbers of animals taken would be so
small as to have a negligible impact on the affected species' stock and upon the
availability of the species for subsistence needs". This ignores the default
reality that the LFA EIS will become the new standard for "acceptable" sound
impacts for every noise polluter. Specific points from all the received comments
must be addressed by the DEIS authors, who will then publish a Final EIS. If the
National Marine Fisheries Service approves the FEIS the LFA will be allowed to
operate, unless a court case intervenes. The FEIS will also be a Biological
Assessment for NMFS. NMFS will issue a Biological Opinion that may include
demands and changes but from much that we've seen recently from NMFS we don't
expect much help for marine mammals.
How does the LFA affect the marine environment? A Vertical Line Array of 18
projectors will transmit combined sequences of hums, sweeps or continuous
frequencies, from a repertoire of signals controlled by computers, for 6-100
seconds (even a 100 second sequence is euphemistically called a "ping") between
100-500Hz. Intervals between signals are nominally 6-15 minutes while echoes
return, for a duty cycle of 10-20%. In a challenging military scenario the LFA
might transmit continuously from ten to 24 hours, resulting in 100 "pings" or
more. The cumulative effect of repeated sounds is known to magnify acoustical
impacts. These are among the loudest controlled sounds ever made by humans in
the oceans. No one knows the full impact potential, so caution should be the
rule.
The fundamental flaw in the DEIS is establishing the outside threshold for
mitigations at the point where a marine animal would receive 180 dB re 1 µPa
(rms), the term for the point at which the DEIS allows that 95% of the large
whales would suffer "non-injurious harassment". This definition is a DEIS
invention, and far louder than most experts would agree with. This term is meant
to suggest that the DEIS complies with "Level B Harassment " as defined by the
Marine Mammal Protection Act, but there is no basis for this. "Non-serious
injury" is used where , for example, the DEIS assumes only transient effects
like temporary deafness ("temporary threshold shift") at 180 dB, in spite of
conflicting expert views. Perhaps it is meant to be vague and confusing.
Continuing the assumption, in a DEIS-conceived graph illustrating percentages as
a "Risk Continuum", about 75% of marine animals receiving more than 170 dB would
incur "non-injurious harassment" , 50% at 165 dB, and only 2.5% at 150 dB.
The 180 dB field extends to 1 kilometer from the source, not surprisingly the
most optimistic maximum mitigation zone. The Navy asserts that they can detect
marine mammals and turtles within this zone using visual searches (the LFA
operates also at night and in high seas), passive arrays (many species of
concern do not make many sounds), and a modified fish finder sonar (very loud
but untested) to locate even small turtles 1 kilometer away, or further away if
they are approaching or in the LFA's path. When animals at risk are detected the
LFA would not operate. Picture a massive naval operation involving hundreds of
vessels pausing while a turtle swims far enough away from the LFA source.
Picture the commanding admiral having a heart attack. Bow riding dolphins and
the fish-finding sonar introduce problems of directed harassment. This HF/M3
sonar puts out 220 dB at 30kHz (within the hearing range of many toothed whales)
and accounts for 70% of the LFA's detection capacity. Any need to mitigate at
received levels below 180 dB extends the mitigation zone beyond any hope of
detecting animals under threat. But that's the Navy's problem, and a primary
flaw in the DEIS.
What about marine life caught close to the LFA when transmissions start?
"Ramp up" is a common mitigation for loud sound sources. Starting at below
operational levels and increasing the signal strength over several transmissions
may allow vulnerable species to vacate the area. Military systems designed for
combat situations don't have the luxury of slowly warming up. Anything close to
the LFA when it starts gets the full volume. Vaguely described as "nearly
collocated with the LFA" is a zone within which an animal would suffer permanent
deafness or death. This is dismissed in the DEIS presumably because few animals
would be impacted. But the potential for one right whale to be under the LFA
vessel and hit by a full force LFA signal was the probable motivation the Navy
needed to declare much of the continental shelf East of North America off limits
to LFA operations. They know one dead right whale is too many. The same rule
does not apply elsewhere.
Where did the 180 dB level come from? Obscurely referenced in the DEIS it may
have come from 1997's High Energy Seismic Survey workshop, where the expert
panel concluded that "they were "apprehensive" about levels above 180 dB re 1
µPa (rms), with respect to the behavioral, physiological, and hearing effects on
marine mammals in general." 180 dB was the level at which the HESS experts felt
damage was likely to occur. Although they added that "the 180 dB radius...is
recommended as the safety zone distance to be used for all seismic surveys
within the Southern California study area" it is vital to understand that
seismic impulses are short bursts of sound that are thought to have less impact
than equivalent received levels of continuous sound, like the LFA. As a rule
experts might consider similar effects from continuous sounds at 10 dB below
impulse values. For the LFA this means that 170 dB might be the threshold value,
but 180 dB is not adequately substantiated.
75% of the exposed animals would still incur "non-injurious harassment", such
as temporary deafness, receiving 170 dB. Assuming that that is somehow
acceptable, how far away could they be to hear this level? The data in all LFA
materials is referenced as "transmission loss", rather than received levels,
because the full "Integrated Source Level" is classified. However, working
backwards from the 180 dB at 1 km, the source level would be about 235 dB. From
another perspective, while individual projectors are limited to 215 dB the full
18 projector array is, according to the DEIS, over 25 dB greater than that. This
suggests that the LFA "integrated" source level" is 240 dB. The complex physics
of underwater acoustics also result in "beam forming" of the LFA sound. It can
even be aimed, satisfying the Navy's need to get loud levels of sound out very
long distances so subs can be located by concentrating the energy. Received
levels are strongly affected by environmental circumstances. In warm waters the
beam is refracted down and up in a wave that may be repeated well over 150
miles. In cold waters the beam doesn't refract as much, and might be caught in a
"surface duct", losing so little power that some creature over 140nm away would
still receive 150 dB. 150 dB has been reported scientifically as having
significant behavioral effects, but these are dismissed in the DEIS. The point
is that at the very least the mitigation zone around the LFA source should be
based on the maximum operational distance at which an appropriate threshold
level is received. CSI argues that, according to all the experts, and an
overwhelming need to invoke the Precautionary Principle to cushion our
collective ignorance, 180 dB is far to loud to be considered as the beginning
point of mitigations. The DEIS plainly argues that nothing need be done
regarding LFA operations unless a marine animal is detected within 1km, within
which 180 dB would be received.
The effects of cumulative noise are also poorly known, but considered
significant by all the experts. The DEIS does discuss 170 dB, in the context of
a "single ping equivalent". Admitting that "there is a very limited basis for
determining the potential effects of repeated exposures for marine mammals,
...(it is) postulated that the risk threshold is lowered by 5 dB for every
tenfold increase in the number of sounds in the exposure." Their example uses
100 pings at 170 dB as equal to 180 dB. During a full military exercise it may
be likely to transmit 100 pings. The time this takes is not relevant. If 100
"pings" are received at 170 dB, and that is equivalent to a 180 dB impact then
it is logical that the realistic mitigation zone must be equal to the range at
which a marine animal would be exposed to a "single ping equivalent". Even if we
allow 180 dB we must factor in cumulative impacts, and this extends the physical
mitigation zone well beyond 1 km, perhaps as much as 40km from the source for
170 dB "pings". The DEIS fails to do this based on a maximum number of pings
scenario. If they argue that affected whales would likely swim away we would
reply that in far too many cases whales have become too accommodated to human
impacts, until it is suddenly and finally too late. Those that did flee might be
forced from areas significant for reproduction, feeding, social cohesion, and
migration. Again, the DEIS considers all behavioral effects irrelevant. the DEIS
obscures the point that no matter how many creatures receive very loud LFA
sounds, anything less than 180 dB of the LFA signal is dismissed; 180 dB is
where mitigations start.
In error the DEIS dismisses the potential for large whales to be harmed by
loud sounds because whales themselves make loud sounds. The mechanisms whales
have for protecting their ears can "lock up" fragile structures, but they are
designed for the whale's own noises; there is no evidence that they could use
this to lessen the LFA's impact. Besides, while enduring an LFA transmission the
whales are denied the use of natural sounds needed to avoid predators, maintain
social groups, and find food and mates by "masking".
The DEIS uses the Scientific Research Program (SRP) as the basis for
dismissing all previous scientific data that find significant impacts at
received levels well below 180 dB, in fact down to 120 dB. Preliminary
conclusions and data from the SRP were contained in the separate Technical
Report #1, which was poorly referenced and only available if requested. This
Report contains numerous errors and overall argues that whales were not impacted
significantly, when the research was purposely not designed to cause significant
impacts. The SRP was unable to demonstrate cetacean reactions to levels of sound
comparable to LFA transmissions under operational conditions. Particularly in
the Hawaiian phase, the SRP asserts conclusions from very small samples of
behavior that are questionably interpreted to the LFA's benefit. It ignores
anecdotal reports and some aerial surveys in Hawaii that showed that whales
might have moved away from the LFA. There was no directed survey of humpback
distribution before, during and after the LFA operation.
One glaring omission in the SRP is any data on any toothed whales. Again this
was a Naval budgetary decision that limited the research potential of the
Hawaiian SRP phase. The sperm whale is known to go silent and flee human sounds,
suggesting impacts on feeding, reproduction, and social structures. Along with
beaked and bottlenose whales, they are deep diving. The DEIS does discuss the
extra impacts on deep divers, but ignores the sperm whale because the population
numbers are relatively high; a number of deaths would not do enough harm.
"Biological significance" is measured only as a high percentage of risk to a
whole population; it doesn't count unless many will be killed .The SRP is
referenced in the back of the DEIS as Technical Report #1 (TR#1), an only
slightly revised version of the "Quick Look" reports done after each SRP phase.
The "Quick Looks" were not meant to stand as definitive science. If the TR is
the only data available to DEIS authors it should be assumed to reflect
additional and revised analyses. Nothing else is known to be publicly available
for objective assessment. Unfortunately there are problems with chart labels,
editing, wording and data presentation that leave reasonable reviewers wondering
how some conclusions are reached. For example, in spite of being unable to get a
reasonably constant received level to targeted singing humpbacks in Hawaii, the
TR tries to extrapolate from a very small sample size, including individuals
that never received levels over 130 dB, that most singing whales did not stop
because of the LFA. Some examples do not clarify this conclusion, but rather
leave a reviewer with several interpretations. In any case, if a whale stopped
singing the TR makes an effort to dismiss the LFA as the cause. The language
used is in stark contrast to the cautious, deliberate wording of draft protocols
and permit requests for the SRP. One is also left to wonder why the Hawaiian
phase was scheduled over a known period of significant pre migratory
redistribution of the humpbacks near Hawaii, leaving enormous and unanswered
allegations that the LFA was a partial cause for whales moving away. There were
no associated surveys before, during and after the LFA that would have allowed
adequate and independent judgment of the LFA. Observations were based on single,
targeted whales, not the overall population that could hear the LFA at levels of
140 or 120 dB. There were aerial surveys but these were not coordinated with LFA
operations and leave so many questions unanswered that they are also being used
in a legal case that argues that many whales left the area. All of these limits
are the result of budget limits imposed the Navy that ultimately leave too many
results in question. In addition there were a considerable number of anecdotal
comments from Hawaiian locals knowledgeable about "their" whales that were never
presented and formatted to fit into the SRP analysis. They are simply
dismissed.
There are many flaws in the DEIS. However, unless contested the DEIS will be
accepted as presented and the LFA will become operational. Your comment may make
the difference. Thank you for writing your LFA DEIS comments prior to the 28
October deadline.
Noise in the Oceans
There is an ever-increasing amount of noise in the oceans caused by human
activities. This is of particular concern because very little is known about the
effects of such noise on cetaceans and other marine life. Several articles in
Whales Alive! since 1995 have focused on the Scripps Institution of
Oceanography's Acoustic Thermometry of Ocean Climate (ATOC) project, and on the
Navy's Low Frequency Active Sonar (LFA) system, two projects that have helped to
shock the world into paying more attention to the problem of noise in the oceans
because of the high intensity of noise that these projects have introduced into
the oceans.
For the most up-to-date information on this issue, read the three-part series
from CNN called "Making Waves":
Also, the Natural Resources Defense Council has published a major report,
"Sounding the Depths: Supertankers, Sonar and the Rise of Undersea
Noise". Read the on-line version of the report on the NRDC web site at http://www.nrdc.org/nrdcpro/sound/sdinx.html.
Additional web resources regarding noise in the oceans:
On-Line Petition to Save The Whales
Greenpeace USA has launched a virtual campaign to "save the whales". Its
on-line petition, located at http://www.greenpeaceusa.org/save/alerts/whalepetition.htm
supports the establishment of a global whale sanctuary, and provides background
details on the whaling industry and controversy.
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© Copyright 1999, Cetacean Society International, Inc.
Updated: 26 July 1999
URL for this page: http://elfi.com/csiupdat.html
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