Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Conducting the Precision Strike Weapon (PSW) Testing and Training by Eglin Air Force Base in the Gulf of Mexico, 48675-48691 [05-16390]
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Federal Register / Vol. 70, No. 160 / Friday, August 19, 2005 / Notices
Instructions to the U.S. Customs and
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The Department will instruct CBP to
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the subject merchandise produced and
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are participating.
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responsibility concerning the
disposition of proprietary information
disclosed under APO in accordance
with 19 CFR 351.306. Timely written
notification of the return/destruction of
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violation.
This notice is published in
accordance with sections 751(b) and
777(i)(1) of the Act, and section
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Dated: August 12, 2005.
Barbara E. Tillman,
Acting Assistant Secretary for Import
Administration.
[FR Doc. E5–4540 Filed 8–18–05; 8:45 am]
BILLING CODE: 3510–DS–S
DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric
Administration
[I.D. 022304A]
Taking and Importing Marine
Mammals; Taking Marine Mammals
Incidental to Conducting the Precision
Strike Weapon (PSW) Testing and
Training by Eglin Air Force Base in the
Gulf of Mexico
National Marine Fisheries
Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA),
Commerce.
ACTION: Notice of issuance of an
incidental harassment authorization.
AGENCY:
SUMMARY: In accordance with provisions
of the Marine Mammal Protection Act
(MMPA) as amended, notification is
hereby given that an Incidental
Harassment Authorization (IHA) to take
marine mammals, by harassment,
incidental to testing and training during
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Precision Strike Weapon (PSW) tests in
the Gulf of Mexico (GOM), a military
readiness activity, has been issued to
Eglin Air Force Base (Eglin AFB).
DATES: Effective from July 28, 2005,
through July 27, 2006.
ADDRESSES: The application, a list of
references used in this document, and/
or the IHA are available by writing to
Steve Leathery, Chief, Permits,
Conservation and Education Division,
Office of Protected Resources, National
Marine Fisheries Service, 1315 EastWest Highway, Silver Spring, MD
20910–3225, or by telephoning the
contact listed here. A copy of the Final
Environmental Assessment (Final EA) is
available by writing to the Department
of the Air Force, AAC/EMSN, Natural
Resources Branch, 501 DeLeon St., Suite
101, Eglin AFB, FL 32542–5133.
Documents cited in this notice may be
viewed, by appointment, during regular
business hours, at the aforementioned
address.
FOR FURTHER INFORMATION CONTACT:
Kenneth R. Hollingshead, NMFS, 301–
713–2055, ext 128.
SUPPLEMENTARY INFORMATION:
Background
Sections 101(a)(5)(A) and 101(a)(5)(D)
of the Marine Mammal Protection Act
(16 U.S.C. 1361 et seq.)(MMPA) direct
the Secretary of Commerce (Secretary)
to allow, upon request, the incidental,
but not intentional taking of small
numbers of marine mammals by U.S.
citizens who engage in a specified
activity (other than commercial fishing)
within a specified geographical region if
certain findings are made and
regulations are issued or, if the taking is
limited to harassment, a notice of a
proposed authorization is provided to
the public for review. In 2004, The
National Defense Authorization Act
(NDAA) (Public Law 108–136) amended
section 101(a)(5) of the MMPA to
exempt military readiness activities
from the ‘‘specified geographical
region’’ and ‘‘small numbers’’
requirements.
An authorization may be granted if
NMFS finds that the taking will have a
negligible impact on the species or
stock(s), will not have an unmitigable
adverse impact on the availability of the
species or stock(s) for subsistence uses,
and if the permissible methods of taking
and requirements pertaining to the
monitoring and reporting of such
takings are set forth. NMFS has defined
‘‘negligible impact’’ in 50 CFR 216.103
as ’’...an impact resulting from the
specified activity that cannot be
reasonably expected to, and is not
reasonably likely to, adversely affect the
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48675
species or stock through effects on
annual rates of recruitment or
survival.z4’’
Section 101(a)(5)(D) of the MMPA
established an expedited process by
which citizens of the United States can
apply for an authorization to
incidentally take small numbers of
marine mammals by harassment. The
NDAA amended the definition of
‘‘harassment’’ in section 18(A) of the
MMPA as it applies to a ‘‘military
readiness activity’’ to read as follows:
(i) any act that injures or has the significant
potential to injure a marine mammal or
marine mammal stock in the wild [Level A
harassment]; or (ii) any act that disturbs or
is likely to disturb a marine mammal or
marine mammal stock in the wild by causing
disruption of natural behavioral patterns,
including, but not limited to, migration,
surfacing, nursing, breeding, feeding, or
sheltering, to a point where such behavioral
patterns are abandoned or significantly
altered [Level B harassment].
Summary of Request
On February 4, 2004, Eglin AFB
submitted a request for a 1–year IHA
under section 101(a)(5)(D) of the MMPA
and for an authorization under section
101(a)(5)(A) of the MMPA (to take effect
after the expiration of the IHA), for the
incidental, but not intentional taking (in
the form of noise-related harassment), of
marine mammals incidental to PSW
testing within the Eglin Gulf Test and
Training Range (EGTTR) for the next 5
years. The EGTTR is described as the
airspace over the GOM that is controlled
by Eglin AFB; it is also referred to as the
‘‘Eglin Water Range.’’
PSW missions involve air-to-surface
impacts of two weapons, the Joint Airto-Surface Stand-off Missile (JASSM)
AGM–158 A and B and the smalldiameter bomb (SDB) (GBU–39/B) that
result in underwater detonations of up
to approximately 300 lbs (136 kg) and
96 lbs (43.5 kg, double SDB) of net
explosive weight (NEW), respectively.
The JASSM is a precision cruise
missile designed for launch from
outside area defenses to kill hard,
medium-hard, soft, and area-type
targets. The JASSM has a range of more
than 200 nautical miles (nm) (370
kilometers (km)) and carries a 1,000–lb
(453.6 kg) warhead. The JASSM has
approximately 300 lbs (136 kg) of TNT
equivalent NEW. The explosive used is
AFX–757, a type of plastic bonded
explosive (PBX) formulation with higher
blast characteristics and less sensitivity
to many physical effects that could
trigger unwanted explosions. The
JASSM would be launched from an
aircraft at altitudes greater than 25,000
ft (7620 m). The JASSM would cruise at
altitudes greater than 12,000 ft (3658 m)
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for the majority of the flight profile until
it makes the terminal maneuver toward
the target. The JASSM exercise involves
a maximum of two live shots (single)
and 4 inert shots (single) each year for
the next 5 years. One live shot will
detonate in water and one will detonate
in air. Detonation of the JASSM would
occur under one of three scenarios: (1)
Detonation upon impact with the target
(about 5 ft (1.5 m) above the GOM
surface); (2) detonation upon impact
with a barge target at the surface of the
GOM; or (3) detonation at 120
milliseconds after contact with the
surface of the GOM.
The SDB is a glide bomb. Because of
its capabilities, the SDB system is an
important element of the Air Force’s
Global Strike Task Force. The SDB has
a range of up to 50 nm (92.6 km) and
carries a 217.4–lb (98.6 kg) warhead.
The SDB has approximately 48 lbs (21.7
kg) of TNT equivalent NEW. The
explosive used is AFX–757. Launch
from an aircraft would occur at altitudes
greater than 15,000 ft (4572 m). The SDB
would commence a non-powered glide
to the intended target. The SDB exercise
involves a maximum of six live shots a
year, with two of the shots occurring
simultaneously, and a maximum of 12
inert shots, with up to two occurring
simultaneously. Detonation of the SDBs
would occur under one of two
scenarios: (1) Detonation of one or two
bombs upon impact with the target
(about 5 ft (1.5 m)above the GOM
surface), or (2) a height of burst (HOB)
test: Detonation of one or two bombs 10
to 25 ft (3 to 7.6 m) above the GOM
surface. No underwater detonations of
the SDB are planned.
The JASSM and SDBs would be
launched from B–1, B–2, B–52, F–15, F–
16, F–18, or F–117 aircraft. Chase
aircraft would include F–15, F–16, and
T–38 aircraft. These aircraft would
follow the test items during captive
carry and free flight but would not
follow either item below a
predetermined altitude as directed by
Flight Safety. Other assets on site may
include an E–9 turboprop aircraft or
MH–60/53 helicopters circling around
the target location. Tanker aircraft
including KC–10s and KC–135s would
also be used. A second unmanned barge
may also be on location to hold
instrumentation. Targets include a
platform of five containers strapped,
braced, and welded together to form a
single structure and a hopper barge,
typical for transportation of grain.
The proposed Eglin AFB action would
occur in the northern GOM in the
EGTTR. Targets would be located in
water less than 200–ft (61–m) deep and
from 15 to 24 nm (27.8 to 44.5 km)
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offshore, south of Santa Rosa Island and
south of Cape San Blas.
Comments and Responses
A notice of receipt of Eglin AFB’s
application and proposed IHA was
published in the Federal Register on
April 22, 2004 (69 FR 21816). That
notice described, in detail, Eglin AFB’s
proposed activity, the marine mammal
species that may be affected by the
activity, and the anticipated effects on
marine mammals. During the 30–day
public comment period, substantial
comments were received from the
Marine Mammal Commission
(Commission), the Gulf Restoration
Network (GRN), and the Acoustic
Ecology Institute (AEI). Other comments
received from individuals on this
proposed action only expressed either
support for, or concern over, missile
launches based on a news article.
MMPA Concerns
Comment 1: The GRN has concerns
that NMFS proposes to issue a 1–year
IHA, followed by a 5–year authorization
to Eglin AFB. The GRN is unclear why
NMFS is presently contemplating the
issuance of an IHA when it has already
stated its intention to propose
regulations. The GRN asks whether the
interim action is being considered to
enable Eglin AFB and/or NMFS to
complete an in-depth environmental
analysis of the potential long-term
impacts of the activity prior to making
a final decision on the regulations.
Alternatively, GRN asks, is this an
attempt to essentially allow Eglin AFB
a 6–year LOA, which GRN believes
would be impermissible under the
MMPA?
Response: NMFS proposes to issue a
1–year IHA to Eglin AFB for its
activities over the next 12 months.
Subsequent authorizations will likely
proceed under section 101(a)(5)(A) of
the MMPA, which allows for take
authorizations over a 5–year time
horizon. The alternative to issuance of
Letters of Authorization (LOAs) under
section 101(a)(5)(A) regulations would
be to continue processing applications
under section 101(a)(5)(D) of the
MMPA, and, presumably, issue IHAs
annually to Eglin for PSW activities.
Either way, the public would be
provided another opportunity to
comment on Eglin AFB’s application
and NMFS’ proposed action. We
disagree that it is not permissible to
follow a one-year IHA with a 5–year
rule and regulations that govern take
authorizations. The MMPA does not
limit the number of times or the period
of time over which an applicant can
receive an incidental take authorization
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so long as all the requirements are met.
For our determination under the
National Environmental Policy Act
(NEPA), see that section later in this
document.
Comment 2: The Commission notes
that the proposed weapons test appear
to fit within the definition of a ‘‘military
readiness activity’’ as defined in section
315(f) of Public Law 107–314, which
includes ‘‘the adequate and realistic
testing of military equipment, vehicles,
weapons, and sensors for proper
operation and suitability for combat
use.’’ As such, the revised definition of
harassment adopted in the NDAA
(Public Law 108–136) would seem to be
applicable in this instance. However,
NMFS’ analysis of the small take request
does not seem to have employed this
definition. If NMFS’ preliminary
conclusion that no take by serious
injury and/or death is anticipated, and
the potential for temporary or
permanent hearing impairment is low
and will be avoided through the
incorporation of (proposed) mitigation
measures is correct, it may be that no
taking by harassment can be expected
and that no authorization is needed. The
Commission therefore recommends that
NMFS analyze the request for an IHA
and the small take regulations being
contemplated in light of the applicable
definition of the term ‘‘harassment.’’
Although the Commission appreciates
NMFS has yet to promulgate regulations
or take other steps to implement the
new definition, the statutory change
cannot be ignored.
Response: In the preamble to the
notice of proposed authorization and in
this document, NMFS cited the NDAA
definition of Level B harassment for
military readiness activities. While
NMFS believes that the monitoring to be
implemented by Eglin AFB will ensure
that the probability of Level A
harassment will be very low (1–2
animals/year-see Table 4) and mortality
likely to be zero (see Table 3), an
authorization under section 101(a)(5) of
the MMPA is warranted because some
animals may be harassed if the
mitigation and monitoring overlooks an
animal.
Given the scientific uncertainty
associated with predicting animal
presence and behavior in the field,
NMFS accords some deference to
applicants requesting an MMPA
authorization for an activity that might
fall slightly below the NDAA definition
of harassment, so that they are covered
for impacts that may rise to the level of
take. Equally important, such an
authorization also carries with it
responsibilities to implement mitigation
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and monitoring measures to protect
marine mammals.
Marine Mammal Impact Concerns
Comment 3: The GRN is concerned
with Eglin AFB’s and/or NMFS’ claim
that the activity will only result in Level
B harassment. The record before the
agency clearly establishes the potential
for injury (Level A harassment) or even
death among marine mammals as a
result of this testing.
Response: Neither Eglin AFB nor
NMFS have claimed that there is no
potential for incidental injury to occur
as a result of this activity. While the
application calculated that 6–7 marine
mammals may incur a Level A (injury)
harassment, recalculation of the
potential for injury has resulted in a
revised estimate of 1–2 animals
annually. Also the criterion for
mortality is lung hemorrhage calculated
for a small dolphin calf at 31 psi-msec.
For the PSW, the zone of potential
lethality is approximately 75–320 m
(246–1050 ft) around the detonation
point (Table 2). Table 3 provides a risk
analysis that indicates that less than 1
cetacean might be killed annually even
if no mitigation measures were
implemented. However, NMFS believes
that due to the mitigation measures that
Eglin AFB will implement, it is very
unlikely that any cetaceans will be
killed, and injury is also unlikely as a
result of PSW activities.
Comment 4: The GRN notes that the
Federal Register notice states that from
3 to as many as 103 cetaceans would
potentially be exposed annually to 182
dB by the action and GRN contends that
the impact of the action would therefore
be more than negligible and would not
be an appropriate subject of an IHA. The
GRN disagrees with NMFS’ claim that
exposure to sound levels greater than
182 dB on possibly 13 percent of the
GOM cetaceans would constitute only
non-injurious Level B harassment.
Response: Neither Eglin AFB nor
NMFS claim that 13 percent of the GOM
cetacean population might be affected
by Eglin’s PSW activities. As shown in
the proposed authorization notice (69
FR 21816, April 22, 2004), only four of
the 29 species/stocks of marine
mammals that inhabit the GOM would
be within the area offshore Eglin AFB.
Of the high estimate of 103 cetaceans
that might be subject to sound exposure
levels (SELs) of 182 dB re 1 microPa2–
s or higher, roughly half would be
bottlenose dolphins and half would be
Atlantic spotted dolphins. No more than
a single Kogia individual might be
subject to an SEL of 182 dB re 1
microPa2–s. As a result of an error in
estimating the number of shots, those
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numbers in the application were higher
than currently projected and analyzed
in this document.
The rationale on why exposure to an
SEL of this magnitude would result in
only Level B harassment takes (by TTS)
and why these takings would have only
negligible impacts was discussed in the
proposed IHA authorization Federal
Register notice with reference to the
scientific basis for that reasoning. That
information is also provided in detail
later in this document. To assess
impacts on marine mammals from
explosives, NMFS and Eglin used the
energy flux density (EFD) metric. This is
also explained in the proposed IHA
notice and later in this document.
Comment 5: Citing from the Minerals
Management Service’s 2002 Draft
Programmatic EA for GOM seismic
activities, the GRN notes that a received
sound pressure level of 180 dB re 1
micro Pa (rms) or greater is an
indication of potential concern about
temporary and/or permanent injury (to
cetaceans, such as sperm whales). Thus,
GRN believes, there is significant
uncertainty as to whether Level A
harassment would be limited to ‘‘nearly
3 cetaceans’’ or could instead affect 103
cetaceans. In the face of this
uncertainty, the GRN would contend
that the no action alternative is
appropriate.
Response: The principal metric
employed for determining harassment,
injury and mortality in this action is
EFD, not sound pressure levels. The
scientific basis for employing this
metric is explained in detail in Eglin’s
application and later in this document.
Use of the energy metric has been
employed in the shock trials of the USS
SEAWOLF (see 63 FR 66069, December
1, 1998) and USS WINSTON S.
CHURCHILL (66 FR 22450, May 4,
2001).
Comment 6: The Commission remains
concerned that NMFS continues to
categorize temporary threshold shift
(TTS) as constituting Level B
harassment, discounting the potential
that diminishment of hearing capability
in marine mammals, even if only of
limited duration, may cause impairment
that could lead to injury or even death
(e.g. by lowering the ability of an animal
to detect and avoid predators or ships).
The Commission notes, however, that
regardless of whether TTS is considered
Level A or Level B harassment, taking
could be authorized under a section
101(a)(5)(D) IHA, provided that
mortalities do not occur.
Response: As mentioned in previous
Federal Register documents, second
level impacts due to a marine mammal
having a temporary hearing impairment
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cannot be predicted and are, therefore,
speculative. The principal reason that
second level impacts are not considered
in classification is that any Level B
disruption of behavior could, with
suppositions, be seen as potentially
dangerous and, therefore, considered
potential Level A harassment or even
lethal. Similarly, Level A injuries could
be seen as being accompanied by some
disruption of behavior and, therefore,
with both Level B disturbances and
Level A injuries. Such reasoning blurs
the distinctions between the definitions
of harassment. NMFS believes that
Level B harassment, if of sufficient
degree and duration, can be very serious
and require consideration, as has been
done here. Moderate TTS does not
necessarily mean that the animal cannot
hear, only that its threshold of hearing
is raised above its normal level. The
extent of time that this impairment
remains is dependent upon the amount
of initial TS, which depends on the
strength of the received sound and
whether the TTS is in a frequency range
that the animal depends on for receiving
cues that would benefit survival. It
should be noted that increased ambient
noise levels, due to biologics, storms,
shipping, and tectonic events may also
result in short-term decreases in an
animal’s ability to hear normally. NMFS
scientists believe that marine mammals
have likely adopted behavioral
responses, such as decreased spatial
separation, slower swimming speeds,
and cessation of socialization to
compensate for increased ambient noise
or hearing threshold levels.
Ship strikes of whales by large vessels
suggest that at least certain species of
large whales do not use vessel sounds
to avoid interactions. Also, there is no
indication that smaller whales and
dolphins with TTS would modify
behavior significantly enough to be
struck by an approaching vessel.
Finally, a hypothesis that marine
mammals would be subject to increased
predation presumes that the predators
would either not be similarly affected by
the detonation or would travel from
areas outside the impact zone,
indicating recognition between the
signal of a single detonation at distance
and potentially debilitated food sources.
Therefore, NMFS does not believe the
evidence warrants that all (or an
unknown percentage) of the estimated
numbers of Level B harassment be
considered as Level A harassment or as
potential mortalities.
Comment 7: The Commission states
that NMFS seems to discount entirely
the possibility that marine mammals
may be harassed through changes in
behavioral patterns other than by TTS.
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The basis for this conclusion is not clear
from the discussion on page 21819 of
the Federal Register notice. Additional
explanation is needed and should
consider, among other things, whether
marine mammals might alter their use
patterns in the vicinity of detonations,
or even abandon an area, as a result of
infrequent or even a one-time exposure.
Response: NMFS does not have
information to support the
Commission’s hypothesis that marine
mammals would abandon or
significantly alter their natural
behavioral patterns in response to a
single explosive detonation. Contrary to
this hypothesis, NMFS believes that,
unless the mammal was transiting the
area, it is unlikely that a marine
mammal would leave an area that
provides important biological resources
for sustenance and reproductive success
from the sounds from a single distant
water detonation (presuming here that it
is more likely that an animal will spend
the majority of its time in a biologically
important area). In fact, the GOM has
thousands of lightning strikes annually
(approximately 10 strikes per sq km per
year in the GOM with source levels of
about 260 dB re 1 microPa
(peak)(NASA, 2005). It is likely that
marine mammals are evolutionarily
adapted to natural events such as
tectonics and lightning storms, which
have similar characteristics to the
explosives in this action. In the absence
of additional information, NMFS
concludes that a marine mammal may
be startled by the received sound level
from a single explosive detonation if
near enough to the source, but it is
highly unlikely that marine mammals
would abandon or significantly alter
their behavior patterns. Therefore, we
do not believe effects rise to the level of
a significant alteration or abandonment
of natural behavioral patterns, i.e., Level
B harassment. In any case, Level B takes
are counted insofar as we consider TTS
to be Level B harassment.
Comment 8: The Commission believes
that NMFS needs to provide a better
explanation of, and justification for,
using the dual criteria established for
determining non-lethal injury (i.e., the
onset of slight lung hemorrhage and a 50
percent probability for eardrum
rupture).
Response: Explanation and
justification were provided in detail in
both the SEAWOLF and CHURCHILL
Final EISs (DoN 1998 and DoN 2001).
An updated summary for using the dual
injury criteria from those documents is
provided here:
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1. Auditory System Injury
Tympanic membrane (TM) rupture,
while not necessarily a serious or lifethreatening injury, is a useful index of
injury that is well correlated with
measures of permanent hearing loss
(Ketten, 1995, 1998). The occurrence of
50 percent TM rupture has been
correlated to 30 percent permanent
threshold shift (PTS) (Ketten, 1995,
1998) and will be considered as the
index for permanent auditory system
injury. In this response, the criteria will
be explained for conservatively
estimating the range for occurrence of
50–percent TM rupture (30–percent
PTS). Significant occurrence of TM
rupture would be expected at ‘‘near
field’’ ranges significantly closer to the
charge than the ranges for TTS and
onset of PTS. For the CHURCHILL EIS
injury model, TM rupture criteria were
based on a limited number of small
charge underwater explosion tests
conducted with small terrestrial
mammals as reported by both Yelverton
et al. (1973) and Richmond et al. (1973).
TM rupture-specific tests were
conducted with post-mortem dogs
(nominal 25–kg body mass) using 1–lb
(0.45–kg) TNT charges. Additional TM
rupture data from general injury tests
conducted with sheep (nominal 40–kg
body mass) using 0.5–lb and 1–lb (0.23–
kg and 0.45–kg) pentolite charges were
also included.
Damage to terrestrial mammal internal
organs typically has been referenced to
total shock wave impulse (pressure
integrated over time) (Richmond et al.
(1973) and Yelverton et al. (1973)).
Yelverton et al. (1973) state that
eardrum ruptures would occur at sublethal impulses of 20 to 40–psi-msec
(138 to 276–Pa-sec) and that an impulse
of 10–psi-msec (69–Pa-sec) or less
would not cause eardrum ruptures.
Acoustic energy (proportional to the
square of pressure integrated over time)
may be one of the appropriate
parameters for evaluation of the
response of the mammalian ear to the
intensities of underwater noise at least
sufficient to cause TTS. The shock
wave’s EFD appears to be at least as
good an indicator/predictor of auditory
system injury (TM rupture) as impulse
and, for the CHURCHILL shock trial
conditions, provided a means to include
the potential effects of the bottomreflected pressure wave.
Logarithmic interpolation of the test
data for EFDs for 42 percent and 67
percent TM rupture indicates that the
calculated EFD required for the
occurrence of 50 percent TM rupture
(approximately 30 percent PTS) is 1.17
in-lb/in2 (20.44 milli-Joules/cm2). The
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small sample sizes for the reported
terrestrial animal test data in
combination with the inherent
variability in the occurrence of TM
rupture at levels less than
approximately 50 percent preclude
realistic predictions of low percentages
of occurrence of TM rupture.
2. Onset of Slight Lung Injury
Using data from tests with small
terrestrial mammals from Yelverton et
al. (1973) and Richmond et al. (1973),
Goertner (1982) developed a
conservative model for calculating the
ranges for occurrence of two types of
internal organ injury to marine
mammals exposed to underwater
explosion shock waves. The two injury
mechanisms considered are (1) slight
lung hemorrhage, and (2) contusions
and hemorrhage of the gastrointestinal
(G.I.) tract. For lung hemorrhage, the
Goertner model considers lung volume
as a function of animal weight and
depth and considers shock wave
duration and impulse tolerance as a
function of animal weight and depth.
Goertner indicated that slight injury to
the G.I. tract could be related to the
magnitude of the peak shock wave
pressure over the hydrostatic pressure
and would be independent of mammal
size and weight. Slight contusions to the
G.I. tract occurred during small charge
tests (Richmond et al., 1973) when the
peak shock wave pressure was 104 psi
above hydrostatic pressure. Onset of G.I.
tract contusion and onset of slight lung
hemorrhage are injuries from which a
mammal would be expected to recover
on its own and would not be
debilitating. For small mammals,
significant G.I. tract injury (G.I. tract
hemorrhage) would be expected to
occur at ranges significantly closer to
the explosion than the maximum
calculated ranges for the onset of slight
lung injury. Injury ranges determined on
the basis of the Goertner model are most
appropriate for use in regions close to
the explosive charge.
After correcting for the atmospheric
and hydrostatic pressures for the data,
the minimum impulse (I) for predicting
onset of slight lung hemorrhage in a
small mammal is:
I = 19.7 (M/42)1/3 psi-msec, or
I = 136 (M/42)1/3 Pa-sec,
where M is the body mass (in kg) of
the subject animal. Impulse values from
the above equation provide a shallow
depth ‘‘starting point’’ for determining
the maximum range and the
corresponding ‘‘at-depth’’ impulse level
for the specific charge weight and
marine mammal size. A maximum range
should not be calculated using only the
above impulse/body mass relationship
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and the total impulse similitude
equation for a specific explosive.
The modified Goertner model is very
sensitive to mammal weight. By
assuming a small mammal weight for an
impact analysis, the onset of slight
injury range is maximized for
conservatism. Injuries from explosions
in relatively shallow water (i.e., on the
continental shelf) may be exacerbated
by strong bottom-reflected pressure
pulses.
Comment 9: In reviewing NMFS’ May
4, 2001, response to the Commission’s
January 26, 2001, comments (see 66 FR
22456, May 4, 2001), NMFS appears to
agree with the Commission that
eardrum rupture is a questionable
measure of acoustic injury in marine
mammals. NMFS notes that ‘‘(b)ecause
the criterion is based upon land
mammals rather than marine mammals,
and because TM (tympanic membrane)
rupture research has not been
conducted on marine mammals, it is not
the 50–percent rupture itself that is the
criterion used, but the ’impulse’ in psimsec that is associated with other
impacts on the body...the EFD that
causes either the 50 percent TM rupture
or the impulse that causes slight lung
hemorrhage is the real criterion.’’
NMFS’ response further indicates that
‘‘because the impulse estimated to cause
slight lung hemorrhage was more
conservative (i.e., had a greater range),
it is slight lung hemorrhage that is the
defining criterion used for determining
injury in this action, not the EFD used
for 50–percent TM rupture.’’ Based on
this explanation, it appears that the 50
percent probability for eardrum rupture
is not a useful metric in that it cannot
be measured. In essence, the probability
for eardrum rupture substitutes for
another metric (PTS), which also cannot
be measured. Because of these
difficulties, neither metric is ultimately
used in setting the safety zone.
Response: Although non-lethal impact
cannot be measured for wild animals at
the time of the action, acoustic
thresholds for injury have been derived
from tests on terrestrial animals in
water. These thresholds are the best
science available today. For the subject
action, the impact range determined
from the lung injury threshold is the
most conservative. However, in other
actions, the eardrum rupture threshold
may be more conservative. For that
reason, the dual criteria are needed to
use a conservative approach for
determining injury ranges for the variety
of explosive activities considered by
NMFS for incidental take
authorizations.
Comment 10: Related to the previous
comment, the Commission notes that
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both the May 4, 2001, and the April 22,
2004, Federal Register notices give a
value of EFD that would cause 50
percent probability of TM rupture, but
provide no reference for this value and
no indication of the signal waveform or
the time interval over which the energy
density flux is integrated. Before using
this value of EFD as the threshold of
Level A harassment for an
authorization, the applicant or NMFS
needs to provide the waveform and
integration time interval and explain the
scientific basis for this choice.
Response: Explanation and reference
for the EFD value are found in response
to comment 8. The nominal source
waveform at unit distance used for the
Air Force risk assessment modeling is
defined as follows:
p(t) = 0 for t <0
p(t) = pmax exp (-t/t) for t > 0
where p(t) is pressure as a function of
time, t. Pmax represents peak pressure
at unit distance and t is the
characteristic time at unit distance. The
waveform and parameters are estimated
using the similitude formulas of Weston
(1960) (see, e. g., Urick, 1983)(note that
this is the Friedlander waveform).
Consistent with NMFS’ SEAWOLF
and CHURCHILL rulemakings and the
Navy’s NEPA analyses for those actions,
no bubble pulses were included (and are
not considered important for near
surface shots). The waveforms were
’propagated’ using the similitude-based
peak pressures and characteristic times
as functions of distance. The
propagation model was the Navy
standard CASS-GRAB model, modified
to calculate impulse response of the
channel.
At range, the squared pressure for the
entire set of arrivals was integrated over
time, and normalized by the scalar
acoustic impedance, to yield total
energy (i.e., the integration was over the
duration of all arrivals).
Comment 11: The Commission
believes that additional clarification and
justification is needed concerning the
‘‘non-injurious behavioral response’’
threshold proposed in Table 6–1 on
page 14 of the application. The
applicant suggests a level of 6 dB below
TTS (i.e., 176 dB re 1 microPa2-sec) as
a reasonable criterion to assess potential
behavioral responses of marine
mammals. However, neither the
application nor the NMFS notice
provides information as to how this
number was derived. Prior to issuing the
requested authorization, the applicant
or NMFS should provide additional
information to support the scientific
basis for using this criterion.
Response: As noted in the proposed
authorization notice, the PSW action
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consists of single detonations. Based on
the science used to develop the
CHURCHILL criteria, for single
detonations a significant response by a
marine mammal is not expected to
occur other than by TTS. The discussion
in the application and Federal Register
notice is relevant to actions involving
multiple detonations. NMFS will
address comments on this threshold
criterion in an applicable proposed IHA
authorization with multiple
detonations.
Comment 12: The Commission notes
that the Federal Register notice for the
proposed IHA states that, in its
rulemaking on the CHURCHILL ship
shock testing, NMFS adopted two
criteria for estimating the TTS
threshold: 182 dB and 12 psi. The notice
states that the second criterion ‘‘was
introduced to provide a more
conservative safety zone for TTS when
the explosive or the animal approaches
the sea surface (for which the explosive
energy is reduced but the peak pressure
is not).’’ The notice states that ‘‘for large
explosives (2,000 to 10,000 lbs) and
explosives/animals not too close to the
surface, the TTS impact zones for these
two TTS criteria are approximately the
same. However, for small detonations,
some acousticians contend that ranges
for the two TTS thresholds may be quite
different, with ranges for the peak
pressure threshold several times greater
than those for energy.’’ NMFS notes that
the applicant is endorsing an approach
being developed by the Navy for
‘‘scaling’’ the peak pressure threshold in
order to estimate more accurately the
TTS for small detonations while
preserving the safety feature provided
by the peak pressure threshold. The
Commission recommends that, in any
authorization issued to Eglin AFB,
NMFS provide the full set of data,
assumptions, and calculations
considered in its review.
Response: This issue remains under
review by the Navy, the U.S. Air Force
and NMFS. Navy acousticians believe
that Ketten (1995), which summarized
earlier acoustic research, does not fully
support using a 12–psi peak pressure
threshold for TTS for underwater
explosion impacts on marine mammals
from small detonations. The original
basis in Ketten (1995) for the use of the
12–psi threshold for the SEAWOLF and
CHURCHILL actions (which were
10,000 lb (4,536 kg) detonations) is the
use of a combination of in-air and inwater peak pressure measurements
without adjustment for the medium. A
re-examination of the basis for the 12–
psi threshold by Navy acousticians
indicate that, for underwater explosions
of small charges, a higher threshold may
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be warranted. This led the Navy and
Eglin to suggest scaling 12 psi for small
charges, which was used in the
proposed authorization notice and
analysis. Although this issue remains
under review by NMFS and the Navy for
future rulemaking actions (including the
upcoming PSW proposed rule), as an
interim criterion for this IHA, NMFS is
adopting the experimental findings of
Finneran et al. (2002) that TTS can be
induced at a pressure level of 23 psi (at
least in belugas). As explained here, this
is considered conservative since a 23 psi
pressure level was below the level that
induced TTS in bottlenose dolphins.
Finneran et al. (2000; as described in
Finneran et al. (2002)) conducted a
study designed to measure masked TTS
(MTTS) in bottlenose dolphins and
belugas exposed to single underwater
impulses. This study used an
‘‘explosion simulator’’ (ES) to generate
impulsive sounds with pressure
waveforms resembling those produced
by distant underwater explosions. No
substantial (i.e., 6 dB or larger)
threshold shifts were observed in any of
the subjects (two bottlenose dolphins
and 1 beluga) at the highest received
level produced by the ES:
approximately 70 kPa (10 psi) peak
pressure, 221 dB re re 1 micro Pa peakto-peak (pk-pk) pressure, and 179 dB re
1 microPa2–s total EFD. In Finneran et
al. (2002), a watergun was substituted
for the ES because it is capable of
producing impulses with higher peak
pressures and total energy fluxes than
the pressure waveforms produced using
the ES. It was also preferable to other
seismic sources because its impulses
contain more energy at higher
frequencies, where odontocete hearing
thresholds are relatively low (i.e., more
sensitive). Hearing thresholds were
measured at 0.4, 4 and 30 kHz. MTTSs
of 7 and 6 dB were observed in the
beluga at 0.4 and 30 kHz, respectively,
approximately 2 minutes following
exposure to single impulses with peak
pressures of 160 kPa (23 psi), pk-pk
pressures of 226 dB re 1 microPa, and
total EFD of 186 dB re 1 microPa2–s.
Thresholds returned to within 2 dB of
the pre-exposure value approximately 4
minutes post exposure. No MTTS was
observed in the single bottlenose
dolphin tested at the highest exposure
conditions: peak pressure of 207 kPa (30
psi), 228 dB re 1 microPa pk-pk
pressure, and 188 dB re 1 microPa2–s
total energy flux. Therefore, until
additional scientific information is
obtained, NMFS has determined that the
pressure criterion for small explosions
can be raised from 12 psi to 23 psi. At
this time, NMFS believes that setting the
pressure metric at 23 psi is conservative.
It should be noted that the PSW
mission includes only a single JASSM
detonation in water, all other
detonations are in-air detonations.
Analyses indicate that the ranges for the
23– psi TTS metric at depths greater
than 20 ft (6.1 m) are less conservative
than the originally provided ranges for
the 182–dB (re 1 microPa2–s) TTS
energy metric. Conversely, ranges for
the 23–psi TTS metric in air and at the
1–ft (0.3–m) water depth are more
conservative than the ranges originally
provided for the 182–dB energy metric.
For the PSW activity, NMFS will use the
more conservative values to determine
impacts (Table 1).
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Mitigation and Monitoring Concerns
Comment 13: Based on the
information contained in the
application and Federal Register notice,
the Commission believes that NMFS’
preliminary determinations are
reasonable, provided that the proposed
mitigation and monitoring activities are
adequate to detect all marine mammals
in the vicinity of the proposed
operations and sufficient to ensure that
marine mammals are not being taken in
unanticipated ways or numbers. The
Commission notes however, that even
under the best of conditions and using
experienced observers, there is greater
than an 80 percent likelihood that small
cetaceans, particularly species such as
dwarf or pygmy sperm whales, will not
be observed if they are in the vicinity of
the test site. Thus, although there may
be a low probability that certain marine
mammal species will be within the area
where mortalities are considered
possible at the time of weapon
deployment, it is unclear that the
proposed monitoring effort will be
adequate to detect them if they are
present. This being the case, the
proposed monitoring activities may be
insufficient to provide assurance that
marine mammals are not being exposed
to sound pressures or energy levels that
could cause lethal injuries. Thus,
NMFS, before issuing the requested
authorization, should further explain its
rationale for determining that the
takings will only be by harassment.
Response: The monitoring effort for
PSW is similar to that used in previous
ship-shock actions wherein detonations
of 10,000 lbs (4536 kg) were used
without any serious injuries or
mortalities being detected during
extensive follow-up monitoring. While
dwarf/pygmy sperm whales are unlikely
to be in the general area and, therefore,
not subject to potential injury or
mortality, past shock trial exercises
considered the detection of these
species to be 50 percent by vessel
observers and 10 percent by aerial
observers. For the bottlenose and
spotted dolphins, detection by
shipboard observers is 100 percent and
aerial observers at 50 percent giving an
overall detection capability of 90
percent (DON, 1999, Appendix C).
However, for safety reasons, monitoring
personnel will need to vacate the
respective safety zones in advance of
detonation, as explained later in this
document (see Table 6 in Mitigation).
As a result, Eglin AFB and NMFS
calculate an overall monitoring
effectiveness of 30 percent for all
species. Table 3 in this document
indicates that the risk for a lethal take
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of an individual marine mammal from
all PSW exercises with a 30–percent
mitigation effectiveness is less than one
animal.
There is a scientific methodology to
estimate the probability of detecting
marine mammals during vessel
assessment surveys, as explained in
detail in Buckland et al. (1993) and
Barlow (1995). Methodology includes
several components, including the
probability that the mammal will be at
the surface and potentially sightable
while within visual range of the
observers, the probability that an animal
at the surface will in fact be detected,
and the relationship between sighting
probability and lateral distance from the
ship’s trackline. One factor providing
better detection rates for Kogia spp. for
this action is that the vessel observers
will be monitoring a relatively small
area, not conducting track line surveys
at a high rate of speed as done in NMFS
marine mammal abundance surveys. In
addition, Eglin will be conducting aerial
marine mammal surveys over an area of
12.56 nm2 (2–nm (3.7–km) radius),
further precluding animals from
entering the safety zone undetected. As
a result of all of these factors, NMFS is
confident that no marine mammals will
be killed as a result of Eglin’s PSW
activities.
Comment 14: The Commission
recommends that, if NMFS determines
that the potential for lethal injuries is
sufficiently remote to warrant the
issuance of an authorization under
section 101(a)(5)(D) of the MMPA, any
such authorization explicitly require
that operations be suspended
immediately if a dead or seriously
injured animal is found in the vicinity
of the test site, pending authorization to
proceed or issuance of regulations
authorizing such takes under section
101(a)(5)(A) of the MMPA.
Response: Testing consists of a single
exercise with a single detonation with
weeks or months likely between
detonations. As a result, if a seriously
injured or dead marine mammal is
found in the vicinity of the test
operations do not need to be
‘‘immediately suspended,’’ but future
tests will not occur until the serious
injury or mortality has been investigated
as to likely cause.
Comment 15: The GRN and the AEI
find that the proposed mitigation is
inadequate to protect marine species in
the GOM. Both groups claim that visual
monitoring is not an effective method
for detecting all cetaceans. The GRN
notes that sperm whales, for instance,
are known for their extremely long,
deep-water dives. Up to 5000 ft (1524
m) dives have been reported for periods
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up to 2 hours long. The animals would
not be visible to observers in either a
helicopter 250 ft (76.2 m) above the
surface of the water or on board a ship,
and they could easily surface unnoticed
in an area impacted by the testing.
Reliance on visual monitoring is not
sufficient to adequately protect cetacean
populations in the GOM. Instead, if
allowed to proceed with the proposed
activity, Eglin AFB should be required
to use passive acoustic monitoring to
ensure that impacts to protect species
are minimal.
Response: While sperm whales and
other deep-diving marine mammals may
remain submerged for long periods of
time, the proposed action would be
located in waters less than 200 ft (61 m)
deep. This habitat is not expected to be
utilized by sperm whales or beaked
whales. The marine mammal species
that inhabit the waters off Eglin AFB are
the bottlenose dolphin, spotted dolphin
and possibly Kogia. Other than Kogia,
these species are easily sighted from
aircraft and ships. While Kogia are more
difficult to see, restricting exercises to
sea states lower than 4, having aerial
coverage in addition to shipboard
observers, and the small zone for Level
A harassment, should eliminate the
likelihood that Kogia or other marine
mammal species would be injured or
killed. Therefore, requiring the use of
passive acoustics is not warranted.
Comment 16: The GRN is also
concerned by Eglin AFB’s apparent
emphasis on post-mission monitoring
(affording 2 hours of aerial surveys after
the activity and only one hour of
continuous aerial surveying prior to
detonation of the weapons). The GRN
believes that, although post-mission
monitoring is important, major
emphasis should be placed on
preventing harm, not quantifying the
number of dead and injured marine
mammals and sea turtles.
Response: NMFS believes that both
pre-detonation monitoring and postdetonation monitoring are important.
Eglin will begin vessel surveys 5 hours
prior to the test and aerial surveys of the
test site 2 hours prior to the proposed
time of detonation (Eglin, 2004). For
safety reasons, aircraft and ships will
need to begin exiting the area 15
minutes prior to detonation (see Table
6). While it is very unlikely that marine
mammals will enter the relatively small
impact zone between the time vacating
the area and the time of detonation, post
monitoring will provide valuable
information on whether current
mitigation measures are fully effective at
preventing mortality and serious injury.
Comment 17: The AEI believes that
NMFS should consider the use of active
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acoustic systems (i.e., fish-finding
sonar) to identify large schools of fish
and/or individual sea turtles that may
be affected by the bombing exercises.
Response: Large fish schools and sea
turtles will be more effectively sighted
by the marine mammal monitoring
aircraft than by standard ‘‘fish finding’’
sonars. However, to the extent that the
monitoring vessel can utilize its
acoustic equipment to detect fish
schools and sea turtles, NMFS
recommends that it do so. This acoustic
equipment is of low intensity and,
therefore, is not expected to result in
marine mammal harassment. However,
the use of more sophisticated highintensity military sonars are not
recommended for use as a mitigation/
monitoring tool here because of its
potential impacts to marine mammals
and other marine life.
Comment 18: The AEI notes that the
recent calibration test for LamontDoherty Earth Observatory’s marine
seismic array in the GOM indicates that
in relatively shallow water, loud lowfrequency acoustic sources may lead to
received levels of concern at greater
distances than current models would
suggest. As a result, received level
models of the bombing exercises should
be based at least on the most recent
propagation models. Also, the most
reliable safety radii would be
determined by real-world tests in the
areas planned for the exercises.
Response: The model employed by LDEO for seismic arrays is different from
the model used by Eglin and the Navy
for explosives. The subject risk
assessment employs the CASS/GRAB
Navy Standard propagation model and
Navy Standard environmental databases
(including bathymetry, sound speed,
and 15–parameter geo-acoustic
sediment properties). These are
considered state of the art. The
propagation model starts with impulse
response and accounts for multipath
propagation in the water column and in
the sediments. Hence, it estimates the
effects of the ’bottom’ in shallow water.
For sediments like those found at the
coastal water sites for Eglin’s risk
assessment, propagation of sound
energy at the lower frequencies (below
several hundred Hertz) is generally
much better than that in deep water.
This enhanced propagation for energy
metrics is included in the range
estimates for the risk assessment.
It should be noted that sound
propagation in shallow water has been
a topic of intense study and
measurement for at least 50 years,
primarily by the U.S. Navy, but also by
other nations and international bodies.
Shallow-water bottom
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effects(’reverberant’ multipaths, shallow
water waveguides, low-frequency cutoff,
influence of sea state, etc.) are all
covered in most basic underwateracoustics textbooks (e.g., Urick, 1967).
Comment 19: The GRN questions
whether post-activity monitoring, when
limited to 2 hours, can accurately
estimate the effectiveness of pre-activity
monitoring. While many dead marine
mammals and sea turtles may rise to the
surface immediately after the mission, it
is possible that the lethal impacts of the
activity may not be immediate. As a
result, sea turtles and marine mammals
may resurface days later, float to shore,
and may or may not be reported to a
stranding network.
Response: Considering the extensive
pre-mission mitigation measures
implemented to prevent injury or
mortality, NMFS believes it is
unnecessary to remain at the site with
vessels and aircraft for longer periods of
time after completion of a test. Eglin
AFB will coordinate its activities with
the NMFS stranding network and with
local stranding networks to locate any
stranded marine mammals after an
event. In addition, Eglin AFB maintains
its own stranding network team.
Stranding events are tracked by year,
season and NMFS statistical zone, both
Gulf-wide and along the coastline of
Eglin AFB.
Activity Concerns
Comment 20: The GRN notes that in
the event that a live warhead fails to
explode during the strike, Eglin AFB
will likely detonate the warhead where
it fell to the bottom of the ocean. An
underwater detonation creates a much
larger chance of injury or death to all
marine species, yet Eglin does not
provide an adequate description of the
level of potential impact to protected
species taken under that scenario.
Response: The noise analysis was
conservatively modeled by Eglin for 20
ft (6 m) below the surface in order to
cover any water depth, including
detonation on the sea bottom. There
would be no difference in the noise
zone of influence from what is modeled
and mitigated from a 20–ft (6 m) depth
detonation and a bottom detonation.
However, the missile itself is
programmed to lose power and will not
detonate after 15 minutes. Therefore, it
is safe to retrieve the missile after 15
minutes and they do not need to be
detonated on-site.
Description of Marine Mammals
Affected by the Activity
There are 29 species of marine
mammals documented as occurring in
Federal waters of the GOM. Information
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on those species that may be impacted
by this activity are discussed in the
Eglin AFB application and the Draft EA.
A summary of that information is
provided in this section.
General information on these species
can be found in Wursig et al. (2000. The
Marine Mammals of the Gulf of Mexico,
TAMU Press, College Station, TX) and
in the NMFS Stock Assessment Reports
(Waring, 2002). This latter document is
available at: https://www.nmfs.noaa.gov/
protlres/PR2/
StocklAssessmentlProgram/
sars.html#Stock Assessment Reports
Marine mammal species that
potentially occur within the EGTTR
include several species of cetaceans and
one sirenian, the West Indian manatee.
During winter months, manatee
distribution in the GOM is generally
confined to southern Florida. During
summer months, a few may migrate
north as far as Louisiana. However,
manatees primarily inhabit coastal and
inshore waters and rarely venture
offshore. PSW missions would be
conducted offshore. Therefore, effects
on manatees are considered very
unlikely.
Cetacean abundance estimates for the
study area are derived from GulfCet II
(Davis et al., 2000) aerial surveys of the
continental shelf within the Minerals
Management Service Eastern Planning
Area, an area of 70,470 km2. Texas A&M
University and NMFS conducted these
surveys from 1996 to 1998. Abundance
and density data from the aerial survey
portion of the survey best reflect the
occurrence of cetaceans within the
EGTTR, given that the survey area
overlaps approximately one-third of the
EGTTR and nearly the entire continental
shelf region of the EGTTR where
military activity is highest. The GulfCet
II aerial surveys identified different
density estimates of marine mammals
for the shelf and slope geographic
locations. Only the shelf data is used
because PSW missions will only be
conducted on the shelf.
In order to maximize species
conservation and protection, the species
density estimate data were adjusted to
reflect more realistic encounters of these
animals in their natural environment.
Refer to ‘‘Conservative Estimates of
Marine Mammal Densities’’ in this
document and Eglin AFB’s application
for more information on density
estimates. A brief description of each
marine mammal species observed
during GulfCet II aerial surveys on the
shelf that has the potential to be present
in the PSW test area is summarized
here.
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Atlantic Bottlenose Dolphins (Tursiops
truncatus)
Bottlenose dolphins are distributed
worldwide in tropical and temperate
waters. In the GOM, several coastal and
offshore stocks have been identified (see
Waring et al. 2002) and one stock occurs
in the inshore waters of the entire GOM.
Waring et al. (2002) provides the
following minimum population
estimates for the GOM bottlenose
dolphin stocks: outer shelf, 43,233; shelf
and slope, 4,530; western Gulf, 2,938;
northern Gulf, 3,518; eastern Gulf,
8,953; and Bay, Sound & Estuarine
waters, 3,933. Baumgartner et al. (2001)
suggest a bimodal distribution in the
northern GOM, with a shelf population
occurring out to the 150–m (492 ft)
isobath and a shelf break population out
to the 750–m (2461 ft) isobath.
Occurrence in water with depth greater
than 1,000 m (3281 ft) is not considered
likely. Migratory patterns from inshore
to offshore are likely associated with the
movements of prey rather than a
preference for a particular habitat
characteristic (such as surface water
temperature) (Ridgeway, 1972; Irving,
1973; Jefferson et al., 1992).
The average herd or group size of
Atlantic bottlenose dolphins in shelf
and slope waters was approximately
four and 10 individuals, respectively,
per herd as determined by GulfCet II
surveys of eastern Gulf waters (Davis et
al., 2000). The diet of Atlantic
bottlenose dolphins consists mainly of
fish, crabs, squid, and shrimp (Caldwell
and Caldwell, 1983).
Atlantic Spotted Dolphins (Stenella
frontalis)
Atlantic spotted dolphins are endemic
to the tropical and warm temperate
Atlantic Ocean. This species ranges
from the latitude of Cape May, NJ, along
mainland shores to Venezuela,
including the GOM and Lesser Antilles
(Caldwell and Caldwell, 1983).
Sightings of this species are
concentrated along the continental shelf
and shelf edge (Fritts et al., 1983), but
they also occur farther offshore. At one
time, Atlantic spotted dolphins were
considered to be the most abundant
species of dolphin in offshore waters
(Schmidly, 1981), with most sightings
occurring at an average of 168 km (90.7
nm) offshore. The best available
abundance estimate for this species in
the northern GOM is the combined
estimate of abundance for both the OCS
(39,307, CV=0.31) and oceanic (238,
CV=0.87) waters from 1996 to 2001,
which is 39,545 (CV=0.31)(NMFS,
2003).
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The preferred depth of the spotted
dolphin is believed to be associated
with food availability and water
temperature. The diet of the Atlantic
spotted dolphin consists of squid and
fish.
Dwarf Sperm Whales and Pygmy Sperm
Whales
Dwarf sperm whales (Kogia simus)
commonly inhabit the deeper offshore
water, generally eating squid,
crustaceans, and fish (Caldwell and
Caldwell, 1983), but they do move into
inshore waters during calving season.
The pygmy sperm whale (Kogia
breviceps) has a diet similar to that of
the dwarf sperm whale. Both pygmy and
dwarf sperm whales have been sighted
in the northern GOM primarily along
the continental shelf edge and in deeper
shelf waters during all seasons except
winter (Mullin et al., 1994). The
estimate of abundance for dwarf and
pygmy sperm whales in oceanic waters
is 809 (CV=0.33)(Mullin and Fulling, in
prep), which is the best available
abundance estimate for these species in
the northern GOM. Separate estimates of
abundance cannot be made due to
uncertainty of species identification
(NMFS, 2003). Dwarf and pygmy sperm
whales have a high percentage of
strandings relative to percent
population of all cetaceans (Mullin et
al., 1994).
Impacts to Marine Mammals
Potential impacts to marine mammals
from the detonation of the PSWs and
SDBs include both lethal and non-lethal
injury, as well as Level B behavioral
harassment. Although unlikely due to
the extensive mitigation measures
proposed by Eglin AFB, marine
mammals have the potential to be killed
or injured as a result of a blast due to
the response of air cavities in the body,
such as the lungs and bubbles in the
intestines. Effects are likely to be most
severe in near surface waters where the
reflected shock wave creates a region of
negative pressure called ‘‘cavitation.’’
This is a region of near total physical
trauma within which no animals would
be expected to survive. A second
criterion used by NMFS for categorizing
taking by mortality is the onset of
extensive lung hemorrhage. Extensive
lung hemorrhage is considered to be
debilitating and thereby potentially
fatal. Suffocation caused by lung
hemorrhage is likely to be the major
cause of marine mammal death from
underwater shock waves.
For the acoustic analysis, the
exploding charge is characterized as a
point source. The impact thresholds
used for marine mammals relate to
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potential effects on hearing from
underwater noise from detonations. For
the explosives in question, actual
detonation heights would range from 0
to 25 ft (7.6 m) above the water surface.
Detonation depths would range from 0
to 80 ft (73.2 m) below the surface. To
bracket the range of possibilities,
detonation scenarios just above and
below the surface were used to analyze
bombs set to detonate on contact with
the target barge. Potentially, the barge
may interact with the propagation of
noise into the water. However, barge
effects on the propagation of noise into
the water column cannot be determined
without in-water noise monitoring at the
time of detonation.
Potential exposure of a sensitive
species to detonation noise could
theoretically occur at the surface or at
any number of depths with differing
consequences. As a conservative
measure a mid-depth scenario was
selected to ensure the greatest direct
path for the harassment ranges, and to
give the greatest impact range for the
injury thresholds.
Explosive Criteria and Thresholds for
Impact of Noise on Marine Mammals
Criteria and thresholds that are the
basis of the analysis of PSW noise
impacts to cetaceans were initially used
in U.S. Navy’s environmental impact
statements (EISs) for ship shock trials of
the SEAWOLF submarine and the USS
WINSTON S. CHURCHILL vessel (DON,
1998; DON, 2001) and accepted by
NMFS as representing the best science
available (see 66 FR 22450, May 4,
2001). With a single exception
mentioned in this document, NMFS
believes that the criteria developed for
the shock trials represent the best
science available. The following
sections summarize the information
contained in those actions.
Criteria and Thresholds: Lethality
The criterion for mortality for marine
mammals used in the CHURCHILL Final
EIS is ’onset of severe lung injury.’ This
is conservative in that it corresponds to
a 1 percent chance of mortal injury, and
yet any animal experiencing onset
severe lung injury is counted as a lethal
take. The threshold is stated in terms of
the Goertner (1982) modified positive
impulse with value ‘‘indexed to 31 psims.’’ Since the Goertner approach
depends on propagation, source/animal
depths, and animal mass in a complex
way, the actual impulse value
corresponding to the 31–psi-ms index is
a complicated calculation. The acoustic
threshold is derived from:
I1% = 42.9 (M/34)1⁄3 psi-ms,
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where M is animal mass in kg. Again,
to be conservative, CHURCHILL used
the mass of a calf dolphin (at 12.2 kg),
so that the threshold index is 30.5 psims.
Criteria and Thresholds: Injury (Level A
Harassment)
Non-lethal injurious impacts are
defined in this document as eardrum
rupture (i.e., tympanic-membrane (TM)
rupture) and the onset of slight lung
injury. These are considered indicative
of the onset of injury. The threshold for
TM rupture corresponds to a 50 percent
rate of rupture (i.e., 50 percent of
animals exposed to the level are
expected to suffer TM rupture); this is
stated in terms of an EFD value of 1.17
in-lb/in2, which is about 205 dB re 1
microPa2–s. (Note: EFD is the time
integral of the squared pressure divided
by the impedance in values of dB re 1
microPa2–s.) This recognizes that TM
rupture is not necessarily a lifethreatening injury, but is a useful index
of possible injury that is well-correlated
with measures of permanent hearing
impairment (e.g., Ketten (1998)
indicates a 30 percent incidence of
permanent threshold shift (PTS) at the
same threshold).
Criteria and Thresholds: Non-injurious
Impacts (Level B Harassment)
Marine mammals may also be
harassed due to noise from PSW
missions involving high explosive
detonations in the EGTTR. The
CHURCHILL criterion for non-injurious
harassment from detonations, as
established through NMFS’ incidental
take rulemaking (see 66 FR 22450, May
4, 2001), is temporary (auditory)
threshold shift (TTS), which is a slight,
recoverable loss of hearing sensitivity
(DoN, 2001). The criterion for TTS used
in this document is 182 dB re 1
microPa2–s maximum EFD level in any
1/3–octave band at frequencies above
100 Hz for all toothed whales (e.g.,
sperm whales, beaked whales,
dolphins). (Note: 1/3–octave band is the
EFD in a 1/3–octave frequency band; the
1/3 octave selected is the hearing range
at which the affected species’ hearing is
believed to be most sensitive.) A 1/3–
octave band above 10 Hz is used for
impact assessments on all baleen
whales, but those species do not inhabit
the affected environment of this project.
The CHURCHILL rulemaking also
established a second criterion for
estimating TTS threshold: 12 psi. The
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appropriate application of this second
TTS criterion is currently under debate,
as this 12–psi criterion was originally
established for estimating the impact of
a 10,000–lb (4536–kg) explosive to be
employed for the Navy’s shock trial. It
was introduced to provide a more
conservative safety zone for TTS when
the explosive or the animal approaches
the sea surface (for which cases the
explosive energy is reduced but the
peak pressure is not).
For large explosives (2000 to 10,000
lbs (907–4536 kg)) and explosives/
animals not too close to the surface, the
TTS impact zones for these two TTS
criteria are approximately the same.
However, for small detonations, some
acousticians contend the ranges for the
two TTS thresholds may be quite
different, with ranges for the peak
pressure threshold several times greater
than those for energy. In its application,
Eglin AFB endorsed an approach,
currently being developed by the Navy,
for appropriately ‘‘scaling’’ the peak
pressure threshold, in order to more
accurately estimate TTS for small shots
while preserving the safety feature
provided by the peak pressure
threshold. As such, in its application,
Eglin AFB requested the energy-based
criterion for TTS, 182 dB re 1 microPa2–
s (maximum EFD level in any 1/3–
octave band), be used alone to
conservatively estimate the zone in
which non-injurious (Level B)
harassment of marine mammals may
occur.
NMFS acousticians have reviewed the
scientific basis for this proposal and
agree, in part, with the statements made
by Eglin AFB that the pressure criterion
of 12 psi is not fully supportable for
small charges or when either the charge
or the recipient are at the surface. The
model used in CHURCHILL assumed
the detonation occurred in deep water
with the charge placed below 318 ft (100
m) in depth, and that the bottom depth
is at least 20 times the detonation depth.
In contrast, in PSW missions, both the
detonation and the recipient will be
near the surface in relatively shallow
water. Therefore, although this issue
remains under review by NMFS and the
Navy for future rulemaking actions, as
an interim criterion for this IHA, NMFS
is adopting the experimental findings of
Finneran et al. (2002) that TTS can be
induced at a pressure level of 23 psi (at
least in belugas). As explained here, this
is considered conservative since a 23–
psi pressure level was below the level
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that induced TTS in bottlenose
dolphins.
Finneran et al. (2000; as described in
Finneran et al. (2002)) conducted a
study designed to measure MTTS in
bottlenose dolphins and belugas
exposed to single underwater impulses.
This study used an ‘‘explosion
simulator’’ (ES) to generate impulsive
sounds with pressure waveforms
resembling those produced by distant
underwater explosions. No substantial
(i.e., 6 dB or larger) threshold shifts
were observed in any of the subjects
(two bottlenose dolphins and 1 beluga)
at the highest received level produced
by the ES: approximately 70 kPa (10 psi)
peak pressure, 221 dB re re 1 micro Pa
peak-to-peak (pk-pk) pressure, and 179
dB re 1 microPa2–s total EFD. In
Finneran et al. (2002), a watergun was
substituted for the ES because it is
capable of producing impulses with
higher peak pressures and total energy
fluxes than the pressure waveforms
produced using the ES. It was also
preferable to other seismic sources
because its impulses contain more
energy at higher frequencies, where
odontocete hearing thresholds are
relatively low (i.e., more sensitive).
Hearing thresholds were measured at
0.4, 4 and 30 kHz. MTTSs of 7 and 6 dB
were observed in the beluga at 0.4 and
30 kHz, respectively, approximately 2
minutes following exposure to single
impulses with peak pressures of 160 kPa
(23 psi), pk-pk pressures of 226 dB re 1
microPa, and total EFD of 186 dB re 1
microPa2–s. Thresholds returned to
within 2 dB of the pre-exposure value
approximately 4 minutes post exposure.
No MTTS was observed in the single
bottlenose dolphin tested at the highest
exposure conditions: peak pressure of
207 kPa (30 psi), 228 dB re 1 microPa
pk-pk pressure, and 188 dB re 1
microPa2–s total energy flux. Therefore,
until more scientific information is
obtained, NMFS has determined that the
pressure criterion for small explosions
can be amended from 12 psi to 23 psi.
At this time, NMFS believes that setting
the pressure metric of the dual
explosive criteria at 23 psi is
conservative, while setting the pressure
metric at a higher level has not been
scientifically validated at this time.
Table 2 illustrates estimated zones of
impact for potential mortality, injury
and TTS.
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Criteria and Thresholds: Behavioral
Modification (Sub-TTS)
No strictly sub-TTS behavioral
responses (i.e., Level B harassment) are
anticipated with the JASSM and SBD
test activities because there are no
successive detonations (the 2 SBD
explosions occur almost
simultaneously) which could provide
causation for a behavioral disruption
rising to the level of a significant
alteration or abandonment of behavioral
patterns without also causing TTS. Also,
repetitive exposures (below TTS) to the
same resident animals are highly
unlikely due to the infrequent JASSM
and SBD test events, the potential
variability in target locations, and the
continuous movement of marine
mammals in the northern GOM.
Incidental Take Estimation
For Eglin AFB’s PSW exercises, three
key sources of information are necessary
for estimating potential take levels from
noise on marine mammals: (1) The zone
of influence (ZOI) for noise exposure;
(2) The number of distinct firing or test
events; and (3) the density of animals
that potentially reside within the ZOI.
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Noise ZOIs were calculated for depth
detonation scenarios of 1 ft (0.3 m) and
20 ft (6.1 m) for lethality and for
harassment (both Level A and Level B).
To estimate the number of potential
‘‘takes’’ or animals affected, the adjusted
data on cetacean population information
from ship and aerial surveys were
applied to the various impact zones.
Table 2 in this document give the
estimated impact ranges for various
explosive weights for summer and
wintertime scenarios for JASSM and
SDB. For example, the JASSM, the
range, in winter, extends to 320 m (1050
ft), 590 m (1936 ft) and 3250 m (10663
ft) for potential mortality (31 psi-ms),
injury (205 dB re 1 microPa2–s) and TTS
(182 dB re 1 microPa2–s/23 psi) zones,
respectively. SDB scenarios are for in-air
detonations at heights of 1.5 m (5 ft) and
7.6 m (25 ft) during both seasons.
JASSM detonations were modeled for
near surface (i.e., 1–ft (0.3–m) depth)
and below surface (>20–ft depth (> 6.1
m)). To account for ‘‘double’’ (2 nearly
simultaneous) events, the charge
weights are added (doubled) when
modeling for the determination of
energy estimates (since energy is
proportional to weight). Pressure
estimates only utilize the single charge
weights for these estimates.
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Applying the lethality (31 psi) and
harassment (182 and 205 dB) impact
ranges in Eglin AFB’s Table 2 to the
calculated species densities, the number
of animals potentially occurring within
the ZOIs without implementation of
mitigation was estimated. These results
are presented in Tables 3, 4, and 5 in
this document. In summary, without
any mitigation, a remote possibility
exists for a bottlenose and an Atlantic
spotted dolphins to be exposed to blast
levels sufficient to cause mortality.
Additionally, less than 2 cetaceans
could be exposed to injurious Level A
harassment noise levels (205 dB re 1
microPa2–s), and as few as 31 or as
many as 52 cetaceans (depending on the
season and water depth) would
potentially be exposed (annually) to a
non-injurious (TTS) Level B harassment
noise level (182 dB re 1 microPa2–s).
None of these impact estimates consider
mitigation measures that will be
employed by Eglin AFB to minimize
potential impacts to protected species.
These mitigation measures are described
elsewhere in this document and are
anticipated to reduce potential impacts
to marine mammals, in both numbers
and degree of severity.
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Mitigation and Monitoring
Eglin will survey the Zone of
Influence (ZOI) and a buffer zone
around a planned detonation site. The
buffer zone will be twice the size of the
ZOI. Prior to the planned detonation,
trained observers aboard aircraft will
survey (visually monitor) the ZOI and
buffer area, a very effective method for
detecting sea turtles and cetaceans. The
aircraft/helicopters will fly
approximately 500 ft (152 m) above the
sea surface to allow observers to scan a
large distance. In addition, trained
observers aboard surface support vessels
will conduct ship-based monitoring for
non-participating vessels as well as
protected species. Using 25X power
‘‘Big-eye’’ binoculars, surface
observation would be effective out to
several kilometers.
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Weather that supports the ability to
sight small marine life (e.g., sea turtles)
is required to effectively mitigate
impacts on marine life (DON, 1998).
Wind, visibility, and surface conditions
in the GOM are the most critical factors
affecting mitigation operations. Higher
winds typically increase wave height
and create ‘‘white cap’’ conditions, both
of which limit an observer’s ability to
locate surfacing marine mammals and
sea turtles. PSW missions would be
delayed if the Beaufort scale sea state
are greater than 3.5. This would
maximize detection of marine mammals
and sea turtles.
Visibility is also a critical factor for
flight safety issues. A minimum ceiling
of 305 m (1000 ft) and visibility of 5.6
km (3 nm) is required to support
mitigation and safety-of-flight concerns
(DON, 2001).
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Aerial Survey/Monitoring Team
Eglin will complete an aerial survey
before each mission and train personnel
to conduct aerial surveys for protected
species. The aerial survey/monitoring
team would consist of two observers.
Aircraft provides a preferable viewing
platform for detection of protected
marine species. Each aerial observer
will be experienced in marine mammal
and sea turtle surveying and be familiar
with species that may occur in the area.
Each aircraft would have a data recorder
who would be responsible for relaying
the location, the species if possible, the
direction of movement, and the number
of animals sighted. The aerial
monitoring team would also identify
large schools of fish, jellyfish
aggregations, and any large
accumulation of Sargassum that could
potentially drift into the ZOI. Standard
line transect aerial surveying methods,
as developed by NMFS (Blaylock and
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Shipboard Monitoring Team
Eglin AFB will conduct shipboard
monitoring to reduce impacts to
protected species. The monitoring
would be staged from the highest point
possible on a mission ship. Observers
would be familiar with the marine life
of the area. The observer on the vessel
must be equipped with optical
equipment with sufficient magnification
(e.g., 25X power ‘‘Big-Eye’’ binoculars,
as these have been successfully used in
monitoring activities from ships), which
should allow the observer to sight
BILLING CODE 3510–22–C
Stepwise mitigation and monitoring
procedures for PSW missions are
outlined here.
Pre-mission Monitoring
The purposes of pre-mission
monitoring are to (1) evaluate the test
site for environmental suitability of the
mission (e.g., relatively low numbers of
marine mammals and turtles, few or no
patches of Sargassum, etc.) and (2)
verify that the ZOI is free of visually
detectable marine mammals, sea turtles,
large schools of fish, large flocks of
birds, large Sargassum mats, and large
concentrations of jellyfish (both are
possible indicators of turtle presence).
On the morning of the test, the lead
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surfacing mammals from as far as 11.6
km (6.3 nm) and provide overlapping
coverage from the aerial team. A team
leader would be responsible for
reporting sighting locations, which
would be based on bearing and distance.
The aerial and shipboard monitoring
teams will have proper lines of
communication to avoid
communication deficiencies. The
observers from the aerial team and
operations vessel will have direct
communication with the lead scientist
aboard the operations vessel. The lead
scientist will be a qualified marine
biologist familiar with marine surveys.
The lead scientist reviews the range
conditions and recommends a Go/NoGo decision to the test director. The test
director makes the final Go/No-Go
decision.
Mitigation Procedures Plan
All zones (injury, ZOI and buffer
zones) are monitored. Although
unexpected, any mission may be
delayed or aborted due to technical
reasons. Actual delay times depend on
the aircraft supporting the test, test
assets, and range time. Should a
technical delay occur, all mitigation
scientist would confirm that the test
sites can still support the mission and
that the weather is adequate to support
mitigation.
Five Hours Prior to Mission:
Approximately 5 hours prior to the
mission, or at daybreak, the appropriate
vessel(s) would be on-site in the
primary test site near the location of the
earliest planned mission point.
Observers onboard the vessel will assess
the suitability of the test site, based on
visual observation of marine mammals
and sea turtles, the presence of large
Sargassum mats, and overall
environmental conditions (visibility, sea
state, etc.). This information will be
relayed to the lead scientist.
Two Hours Prior to Mission:
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procedures would continue and remain
in place until either the test takes place
or is canceled. The ZOI and buffer zone
around JASSM missions will be
effectively monitored by shipboard
observers from the highest point of the
vessel. Vessels will be positioned as
close to the safety zone as allowed
without infringing on the missile flight
corridor. The SDB has many mission
profiles and does not have a flight
termination system; therefore, the safety
buffer may be quite large (5–10 nm
radius (9.3–18.5 km)).
PSW mitigation must be regulated by
Air Force safety parameters (pers.
comm. Monteith and Nowers, 2004) to
ensure personnel safety. Therefore,
mitigation effectiveness may be reduced
for some missions due to mandatory
safety buffers which limit the time and
type of mitigation. Even though
mitigation may be limited for SDB
missions, all detonations are above the
water surface (5–25 ft (1.5–7.6 m) above
the surface) and of much smaller net
explosive weight than JASSM. Table 6
describes safety zones and clearance
times for JASSM and SDB missions
(time in minutes).
BILLING CODE 3510–22–S
Two hours prior to the mission, aerial
monitoring would commence within the
test site to evaluate the test site for
environmental suitability. Evaluation of
the entire test site would take
approximately 1 to 1.5 hours. Shipboard
observers would monitor the ZOI and
buffer zone, and the lead scientist
would enter all marine mammals and
sea turtle sightings, including the time
of sighting and the direction of travel,
into a marine animal tracking and
sighting database. The aerial monitoring
team would begin monitoring the ZOI
and buffer zone around the target area.
The shipboard monitoring team would
combine with the aerial team to monitor
the area immediately around the
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Hoggard, 1994; Buckland et al., 1993)
would be used. Aerial observers are
expected to have above average to
excellent sighting conditions at sunrise
to 1.85 km (1 nm) on either side of the
aircraft within the weather limitation
noted previously. Observed marine
mammals and sea turtles would be
identified to the species or the lowest
possible taxonomic level and the
relative position recorded. In order to
ensure adequate daylight for pre- and
post-mission monitoring, the mission
activity would occur no earlier than 2
hours after sunrise and no later than 2
hours prior to sunset.
Federal Register / Vol. 70, No. 160 / Friday, August 19, 2005 / Notices
mission area including both the ZOI and
buffer zone.
One to 1.5 Hours Prior to Launch
As noted in Table 6 and depending
upon the mission, aerial and shipboard
viewers would be instructed to leave the
area and remain outside the safety area
(over 2 nm (3.7 km) from impact for
JASSM and 5–10 nm (9.3–18.5 km) for
SDB). The aerial team would report all
marine animals spotted and the
directions of travel to the lead scientist
onboard the vessel. The shipboard
monitoring team would continue
searching the buffer zone for protected
species as it leaves. The aircraft will
leave the area and land on base. The
surface vessels will stay on the outside
of the safety area until after impact (5–
10 nm for SDB and 2 nm for JASSM).
Fifteen Minutes Prior to Launch and Go/
No-Go Decision Process
Visual monitoring from surface
vessels outside the safety zone would
continue to document any animals that
may have gone undetected during the
past two hours and track animals
moving in the direction of the impact
area.
The lead scientist would plot and
record sightings and bearing for all
marine animals detected. This would
depict animal sightings relative to the
mission area. The lead scientist would
have the authority to declare the range
fouled and recommend a hold until
monitoring indicates that the ZOI is and
will remain clear of detectable animals.
As indicated in the previous table, the
ZOI (for preventing TTS (182 dB re 1
microPa2–s/23 psi)) is estimated for the
specific charge weight being used, the
depth of blast, and the season. The
mission would be postponed if:
(1) Any marine mammal or sea turtle
is visually detected within the ZOI prior
to mission launch. The delay would
continue until the marine mammal or
sea turtle that caused the postponement
is confirmed to be outside of the ZOI
due to the animal swimming out of the
range.
(2) Any marine mammal or sea turtle
is detected in the buffer zone and
subsequently cannot be reacquired. The
mission would not continue until the
last verified location is outside of the
ZOI and the animal is moving away
from the mission area.
(3) Large Sargassum rafts or large
concentrations of jellyfish are observed
within the ZOI. The delay would
continue until the Sargassum rafts or
jellyfish that caused the postponement
are confirmed to be outside of the ZOI
due to either the current and/or wind
moving them out of the mission area.
(4) Large schools of fish are observed
in the water within the ZOI. The delay
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would continue until the large fish
schools are confirmed to be outside the
ZOI.
In the event of a postponement, premission monitoring would continue as
long as weather and daylight hours
allow. Aerial monitoring is limited by
fuel and the on-station time of the
monitoring aircraft. If a live warhead
failed to explode operations would
attempt to recognize and solve the
problem while continuing with all
mitigation measures in place. The
probability of this occurring is very
remote but does exist. Should a weapon
fail to explode, the activity sponsor
would attempt to identify the problem
and detonate the charge with all marine
mammal and sea turtle mitigation
measures in place as described. If a live
warhead fails to explode the weapon is
rendered safe after 15 minutes. The
feasibility and practicality of recovering
the warhead will be evaluated on a caseby-case basis. If at all feasible, the
warhead will be recovered.
It should be noted that for economic
(costs of testing $2 million per test) and
practical (in-air destruction of the
missile) reasons, Eglin AFB will not be
required to terminate an in-flight missile
or bomb due to sighting of a protected
species.
Launch to Impact
Visual monitoring from vessels would
continue to survey the ZOI and
surrounding buffer zone and track
animals moving in the direction of the
impact area. The lead scientist would
continue to plot and record sightings
and bearing for all marine animals
detected. This will depict animal
sightings relative to the impact area.
Post-mission monitoring
Post-mission monitoring is designed
to determine the effectiveness of premission mitigation by reporting any
sightings of dead or injured marine
mammals or sea turtles. Post-detonation
monitoring via shipboard surveyors
would commence immediately
following each detonation; no aerial
surveys would be conducted during this
monitoring stage. The vessels will move
into the ZOI from outside the safety
zone and continue monitoring for at
least two hours, concentrating on the
area down current of the test site.
Although it is highly unlikely that
marine mammals or sea turtles would be
killed or seriously injured by this
activity, marine mammals or sea turtles
killed by an explosion would likely
suffer lung rupture, which would cause
them to float to the surface immediately
due to air in the blood stream. Animals
that were not killed instantly but were
mortally wounded would likely
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48689
resurface within a few days, though this
would depend on the size and type of
animal, fat stores, depth, and water
temperature (DON, 2001). The
monitoring team would attempt to
document any marine mammals or
turtles that were killed or injured as a
result of the test and, if practicable,
recover and examine any dead animals.
The species, number, location, and
behavior of any animals observed by the
observation teams would be
documented and reported to the lead
scientist.
Post-mission monitoring activities
include coordination with marine
animal stranding networks. NMFS
maintains stranding networks along
coasts to collect and circulate
information about marine mammal and
sea turtle standings. Local coordinators
report stranding data to state and
regional coordinators. Any observed
dead or injured marine mammal or sea
turtle would be reported to the
appropriate coordinator.
Summary of Mitigation Plan
The PSW test will be postponed if any
human safety concerns arise, protected
species are sighted within the ZOI, any
protected species is detected in the
buffer zone and subsequently cannot be
reacquired, or a protected species is
moving into the ZOI from the buffer
zone. PSW testing would be delayed if
definitive indicators of protective
species (i.e., large Sargassum mats) were
present. The delay would continue until
the marine mammal, sea turtle, and/or
indicators that caused the postponement
is confirmed to be outside of the ZOI
due to the animal swimming out of the
range.
Avoidance of impacts to pods of
cetaceans will most likely be realized
through these measures since groups of
dolphins are relatively easy to spot with
the survey distances and methods that
will be employed. Typically solitary
marine mammals such as dwarf/pygmy
sperm whales and sea turtles, while
more challenging to detect, will also be
afforded substantial protection through
pre-test monitoring.
The safety vessels would conduct
post-mission monitoring for two hours
after each mission. The monitoring team
would attempt to document any marine
mammals or turtles that were killed or
injured as a result of the test and, if
practicable, recover and examine any
dead animals.
Hard-bottom habitats and artificial
reefs will be avoided to alleviate any
potential impacts to protected habitat.
PSW testing will be delayed if large
Sargassum mats are found in the ZOI.
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Federal Register / Vol. 70, No. 160 / Friday, August 19, 2005 / Notices
Testing will resume only when the mats
move outside of the largest ZOI.
Conservative Estimates of Marine
Mammal Densities
By using conservative mathematic
calculations, conservative density
estimates can serve as a respectable
mitigation technique for take estimates.
Marine mammal densities used to
calculate takes were based on the most
current and comprehensive GOM
surveys available (GulfCet II). The
densities are adjusted for the time the
animals are submerged, and further
adjusted by applying standard
deviations to provide an approximately
99 percent confidence level. As an
example, the density estimates for
bottlenose dolphins range from 0.06 to
0.15 animals/km2 in GulfCet II aerial
surveys of the shelf and slope. However,
the final adjusted density used in take
calculations is 0.81 animals/km2.
Reporting
NMFS will require Eglin AFB to
submit an annual report on the results
of the monitoring requirements. This
annual report will be due within 120
days of the expiration of the IHA. This
report will include a discussion on the
effectiveness of the mitigation in
addition to the following information:
(1) date and time of each of the
detonations; (2) a detailed description of
the pre-test and post-test activities
related to mitigating and monitoring the
effects of explosives detonation on
marine mammals and their populations;
(3) the results of the monitoring
program, including numbers by species/
stock of any marine mammals noted
injured or killed as a result of the
detonations and numbers that may have
been harassed due to undetected
presence within the safety zone; and (4)
results of coordination with coastal
marine mammal/sea turtle stranding
networks.
Research
Although Eglin AFB does not
currently conduct independent Air
Force monitoring efforts, Eglin AFB’s
Natural Resources Branch does
participate in marine animal tagging and
monitoring programs lead by other
agencies. Additionally, the Natural
Resources Branch also supports
participation in annual surveys of
marine mammals in the GOM with
NOAA Fisheries. From 1999 to 2002,
Eglin AFB’s Natural Resources Branch
has, through a contract representative,
participated in summer cetacean
monitoring and research opportunities.
The contractor participated in visual
surveys in 1999 for cetaceans in GOM,
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16:47 Aug 18, 2005
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photographic identification of sperm
whales in the northeastern Gulf in 2001,
and as a visual observer during the 2000
Sperm Whale Pilot Study and the 2002
sperm whale Satellite-tag (S-tag) cruise.
Support for these research efforts is
anticipated to continue.
Eglin AFB conducts other research
efforts that utilize marine mammal
stranding information as a means of
ascertaining the effectiveness of
mitigation techniques. Stranding data is
collected and maintained for the Florida
panhandle and Gulf-wide areas. This is
undertaken through the establishment
and maintenance of contacts with local,
state, and regional stranding networks.
Eglin AFB assists with stranding data
collection by maintaining its own team
of stranding personnel. In addition to
simply collecting stranding data,
various analyses are performed.
Stranding events are tracked by year,
season, and NOAA Fisheries statistical
zone, both Gulf-wide and on the
coastline in proximity to Eglin AFB.
Stranding data is combined with records
of EGTTR mission activity in each water
range and analyzed for any possible
correlation. In addition to being used as
a measure of the effectiveness of
mission mitigation, stranding data can
yield insight into the species
composition of cetaceans in the region.
Endangered Species Act (ESA)
NMFS has issued a biological opinion
regarding the effects of this action on
ESA-listed species and critical habitat
under the jurisdiction of NMFS. That
biological opinion concluded that this
action is not likely to jeopardize the
continued existence of listed species or
result in the destruction or adverse
modification of critical habitat. A copy
of the Biological Opinion is available
upon request (see ADDRESSES).
National Environmental Policy Act
(NEPA)
In December, 2003, Eglin AFB
released a Draft EA on this proposed
activity. On April 22, 2004 (69 FR
21816), NMFS noted that Eglin AFB had
prepared an EA for PSW activities and
made this EA was available upon
request. Eglin AFB has updated that
draft EA.
In accordance with NOAA
Administrative Order 216–6
(Environmental Review Procedures for
Implementing the National
Environmental Policy Act, May 20,
1999), NMFS has reviewed the
information contained in Eglin’s draft
Final EA and determined that the Eglin
AFB EA accurately and completely
describes the proposed action
alternative, reasonable additional
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alternatives, and the potential impacts
on marine mammals, endangered
species, and other marine life that could
be impacted by the preferred alternative
and the other alternatives. Based on this
review and analysis, NMFS is adopting
Eglin’s EA under 40 CFR 1506.3 and has
made its own FONSI. Therefore, NMFS
has determined it is not necessary to
issue a new EA, supplemental EA or an
environmental impact statement for the
issuance of an IHA to Eglin AFB for this
activity. A copy of NMFS’ FONSI for
this activity is available upon request
(see ADDRESSES). A copy of the Eglin
AFB EA for this activity is available by
contacting either Eglin AFB or NMFS
(see ADDRESSES).
Determinations
NMFS has determined that this action
is expected to have a negligible impact
on the affected species or stocks of
marine mammals in the GOM. No take
by serious injury and/or death is
anticipated, and the potential for
temporary or permanent hearing
impairment is low and will be avoided
through the incorporation of the
mitigation measures mentioned in this
document. The information contained
in Eglin’s EA and incidental take
application support NMFS’ finding that
impacts will be mitigated by
implementation of a conservative safety
range for marine mammal exclusion,
incorporation of aerial and shipboard
survey monitoring efforts in the program
both prior to, and after, detonation of
explosives, and delay/postponement/
cancellation of detonations whenever
marine mammals are either detected
within the safety zone or may enter the
safety zone at the time of detonation or
if weather and sea conditions preclude
adequate aerial surveillance. Since the
taking will not result in more than the
incidental harassment of certain species
of marine mammals, will have only a
negligible impact on these stocks, will
not have an unmitigable adverse impact
on the availability of these stocks for
subsistence uses, and, through
implementation of required mitigation
and monitoring measures, will result in
the least practicable adverse impact on
the affected marine mammal stocks,
NMFS has determined that the
requirements of section 101(a)(5)(D) of
the MMPA have been met and the IHA
can be issued.
Authorization
NMFS has issued an IHA to take
marine mammals, by harassment,
incidental to testing and training during
Precision Strike Weapons (PSW) tests in
the Gulf of Mexico for a 1–year period,
provided the mitigation, monitoring,
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Federal Register / Vol. 70, No. 160 / Friday, August 19, 2005 / Notices
and reporting requirements described in
this document and the IHA are
undertaken.
Dated: August 11, 2005.
James H. Lecky,
Director, Office of Protected Resources,
National Marine Fisheries Service.
[FR Doc. 05–16390 Filed 8–18–05; 8:45 am]
BILLING CODE 3510–22–S
DEPARTMENT OF DEFENSE
Office of the Secretary
Notice; Meeting of the Independent
Review Panel To Study the
Relationships Between Military
Department General Counsels and
Judge Advocates General—Open
Meeting
Department of Defense.
Pursuant to the Federal
Advisory Committee Act (FACA), Public
Law 96–463, notice is hereby given that
the Independent Review Panel to Study
the Relationships between Military
Department General Counsels and Judge
Advocates General will hold an open
meeting at the Hilton Crystal City, 2399
Jefferson Davis Highway, Arlington,
Virginia 22202, on August 29, 2005, if
needed, from 8:30 a.m. to 11:30 a.m. and
1 p.m. to 4 p.m.
DATES: August 29, 2005: 8:30 a.m.–11:30
a.m., and 1 p.m.–4 p.m.
ADDRESSES: Hilton Crystal City, 2399
Jefferson Davis Highway,
Arlington,Virginia 22202.
FOR FURTHER INFORMATION CONTACT: Any
member of the public wishing further
information concerning this meeting
may contact: Mr. James R. Schwenk,
Designated Federal Official, Department
of Defense Office of the General
Counsel, 1600 Defense Pentagon,
Arlington, Virginia 20301–1600,
Telephone: (703) 697–9343, Fax: (703)
693–7616, schwenkj@dodgc.osd.mil.
SUPPLEMENTARY INFORMATION: The Panel
will meet on August 29, 2005, from 8:30
a.m. to 11:30 a.m. and 1 p.m. to 4 p.m.,
if needed, to conduct deliberations
concerning the relationships between
the legal elements of their respective
Military Departments. These sessions
will be open to the public, subject to the
availability of space. The Panel has held
eight public hearings and has provided
the public opportunities to address the
Panel both in person and in writing. The
Panel has also deliberated in several
sessions open to the public, including
deliberations on an initial draft of a final
report prepared by the Panel’s staff. The
Panel must complete its report during
August so that Congress may consider it
AGENCY:
SUMMARY:
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16:47 Aug 18, 2005
Jkt 205001
during this legislative session as
envisioned in section 574 of the Ronald
W. Reagan National Defense
Authorization Act for Fiscal Year 2005.
Due to this exceptional circumstance,
the Panel decided to hold its final
deliberation session, if needed, open to
the public, on August 29. This decision,
based on that exceptional circumstance,
was made on August 12, thus making it
impossible for the Department to
provide the 15 calendar days notice
normally required for Panel meetings.
On August 12, the Panel completed
deliberations necessary for the staff to
prepare a final report. If, after reviewing
the final report prepared by the staff,
any member of the Panel believes that
additional deliberations are necessary,
the meeting on August 29 will occur. If
all Panel members believe that the final
report prepared by the staff properly
addresses all issues and no additional
deliberations are necessary, there will
not be a meeting on August 29. Please
call the Designated Federal Official at
the number listed below for additional
information including whether the
meeting scheduled for August 29 will be
held.
Dated: August 16, 2005.
Jeannette Owings-Ballard,
OSD Federal Register Liaison Officer,
Department of Defense.
[FR Doc. 05–16505 Filed 8–16–05; 3:25 pm]
BILLING CODE 5001–06–P
DEPARTMENT OF ENERGY
Federal Energy Regulatory
Commission
[Docket No. CP05–402–000]
Columbia Gas Storage, LLC; Notice of
Petition
August 12, 2005.
Take notice that on August 9, 2005,
Columbia Gas Storage, 20333 State
Highway 249, Suite 400, Houston, TX
77070, filed a petition for Exemption of
Temporary Acts and Operations from
Certificate Requirements, pursuant to
Rule 207(a)(5) of the Commission’s
Rules of Practice and Procedure (18 CFR
385.207(a)(5)), and section 7(c)(1)(B) of
the Natural Gas Act (15 U.S.C.
717(c)(1)(B)), seeking approval of an
exemption from certificate requirements
to perform temporary activities related
to drilling a test well and performing
other activities to assess the feasibility
of developing an underground natural
gas storage facility in Benton County,
Washington, all as more fully set forth
in the application which is on file with
the Commission and open to public
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48691
inspection. The filing may also be
viewed on the Web at https://
www.ferc.gov using the ‘‘eLibrary’’ link.
Enter the docket number excluding the
last three digits in the docket number
field to access the document. For
assistance, call (202) 502–3676 or TYY,
(202) 502–8659.
Any questions regarding the petition
should be directed to Joseph H. Fagan,
Heller Ehrman LLP, 1717 Rhode Island
Ave., NW., Washington, DC 20036–3001
and Phone: 202–912–2162; Fax 202–
912–2020.
There are two ways to become
involved in the Commission’s review of
this project. First, any person wishing to
obtain legal status by becoming a party
to the proceedings for this project
should, on or before the comment date,
file with the Federal Energy Regulatory
Commission, 888 First Street, NE.,
Washington, DC 20426, a motion to
intervene in accordance with the
requirements of the Commission’s Rules
of Practice and Procedure (18 CFR
385.214 or 385.211) and the Regulations
under the NGA (18 CFR 157.10). A
person obtaining party status will be
placed on the service list maintained by
the Secretary of the Commission and
will receive copies of all documents
filed by the applicant and by all other
parties. A party must submit 14 copies
of filings made with the Commission
and must mail a copy to the applicant
and to every other party in the
proceeding. Only parties to the
proceeding can ask for court review of
Commission orders in the proceeding.
Persons who wish to comment only
on the environmental review of this
project, or in support of or in opposition
to this project, should submit an
original and two copies of their
comments to the Secretary of the
Commission. Environmental
commenters will be placed on the
Commission’s environmental mailing
list, will receive copies of the
environmental documents, and will be
notified of meetings associated with the
Commission’s environmental review
process. Environmental commenters
will not be required to serve copies of
filed documents on all other parties.
The Commission’s rules require that
persons filing comments in opposition
to the project provide copies of their
protests only to the applicant. However,
the non-party commenters will not
receive copies of all documents filed by
other parties or issued by the
Commission (except for the mailing of
environmental documents issued by the
Commission) and will not have the right
to seek court review of the
Commission’s final order.
E:\FR\FM\19AUN1.SGM
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Agencies
[Federal Register Volume 70, Number 160 (Friday, August 19, 2005)]
[Notices]
[Pages 48675-48691]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-16390]
-----------------------------------------------------------------------
DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
[I.D. 022304A]
Taking and Importing Marine Mammals; Taking Marine Mammals
Incidental to Conducting the Precision Strike Weapon (PSW) Testing and
Training by Eglin Air Force Base in the Gulf of Mexico
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice of issuance of an incidental harassment authorization.
-----------------------------------------------------------------------
SUMMARY: In accordance with provisions of the Marine Mammal Protection
Act (MMPA) as amended, notification is hereby given that an Incidental
Harassment Authorization (IHA) to take marine mammals, by harassment,
incidental to testing and training during Precision Strike Weapon (PSW)
tests in the Gulf of Mexico (GOM), a military readiness activity, has
been issued to Eglin Air Force Base (Eglin AFB).
DATES: Effective from July 28, 2005, through July 27, 2006.
ADDRESSES: The application, a list of references used in this document,
and/or the IHA are available by writing to Steve Leathery, Chief,
Permits, Conservation and Education Division, Office of Protected
Resources, National Marine Fisheries Service, 1315 East-West Highway,
Silver Spring, MD 20910-3225, or by telephoning the contact listed
here. A copy of the Final Environmental Assessment (Final EA) is
available by writing to the Department of the Air Force, AAC/EMSN,
Natural Resources Branch, 501 DeLeon St., Suite 101, Eglin AFB, FL
32542-5133. Documents cited in this notice may be viewed, by
appointment, during regular business hours, at the aforementioned
address.
FOR FURTHER INFORMATION CONTACT: Kenneth R. Hollingshead, NMFS, 301-
713-2055, ext 128.
SUPPLEMENTARY INFORMATION:
Background
Sections 101(a)(5)(A) and 101(a)(5)(D) of the Marine Mammal
Protection Act (16 U.S.C. 1361 et seq.)(MMPA) direct the Secretary of
Commerce (Secretary) to allow, upon request, the incidental, but not
intentional taking of small numbers of marine mammals by U.S. citizens
who engage in a specified activity (other than commercial fishing)
within a specified geographical region if certain findings are made and
regulations are issued or, if the taking is limited to harassment, a
notice of a proposed authorization is provided to the public for
review. In 2004, The National Defense Authorization Act (NDAA) (Public
Law 108-136) amended section 101(a)(5) of the MMPA to exempt military
readiness activities from the ``specified geographical region'' and
``small numbers'' requirements.
An authorization may be granted if NMFS finds that the taking will
have a negligible impact on the species or stock(s), will not have an
unmitigable adverse impact on the availability of the species or
stock(s) for subsistence uses, and if the permissible methods of taking
and requirements pertaining to the monitoring and reporting of such
takings are set forth. NMFS has defined ``negligible impact'' in 50 CFR
216.103 as ''...an impact resulting from the specified activity that
cannot be reasonably expected to, and is not reasonably likely to,
adversely affect the species or stock through effects on annual rates
of recruitment or survival.z4''
Section 101(a)(5)(D) of the MMPA established an expedited process
by which citizens of the United States can apply for an authorization
to incidentally take small numbers of marine mammals by harassment. The
NDAA amended the definition of ``harassment'' in section 18(A) of the
MMPA as it applies to a ``military readiness activity'' to read as
follows:
(i) any act that injures or has the significant potential to
injure a marine mammal or marine mammal stock in the wild [Level A
harassment]; or (ii) any act that disturbs or is likely to disturb a
marine mammal or marine mammal stock in the wild by causing
disruption of natural behavioral patterns, including, but not
limited to, migration, surfacing, nursing, breeding, feeding, or
sheltering, to a point where such behavioral patterns are abandoned
or significantly altered [Level B harassment].
Summary of Request
On February 4, 2004, Eglin AFB submitted a request for a 1-year IHA
under section 101(a)(5)(D) of the MMPA and for an authorization under
section 101(a)(5)(A) of the MMPA (to take effect after the expiration
of the IHA), for the incidental, but not intentional taking (in the
form of noise-related harassment), of marine mammals incidental to PSW
testing within the Eglin Gulf Test and Training Range (EGTTR) for the
next 5 years. The EGTTR is described as the airspace over the GOM that
is controlled by Eglin AFB; it is also referred to as the ``Eglin Water
Range.''
PSW missions involve air-to-surface impacts of two weapons, the
Joint Air-to-Surface Stand-off Missile (JASSM) AGM-158 A and B and the
small-diameter bomb (SDB) (GBU-39/B) that result in underwater
detonations of up to approximately 300 lbs (136 kg) and 96 lbs (43.5
kg, double SDB) of net explosive weight (NEW), respectively.
The JASSM is a precision cruise missile designed for launch from
outside area defenses to kill hard, medium-hard, soft, and area-type
targets. The JASSM has a range of more than 200 nautical miles (nm)
(370 kilometers (km)) and carries a 1,000-lb (453.6 kg) warhead. The
JASSM has approximately 300 lbs (136 kg) of TNT equivalent NEW. The
explosive used is AFX-757, a type of plastic bonded explosive (PBX)
formulation with higher blast characteristics and less sensitivity to
many physical effects that could trigger unwanted explosions. The JASSM
would be launched from an aircraft at altitudes greater than 25,000 ft
(7620 m). The JASSM would cruise at altitudes greater than 12,000 ft
(3658 m)
[[Page 48676]]
for the majority of the flight profile until it makes the terminal
maneuver toward the target. The JASSM exercise involves a maximum of
two live shots (single) and 4 inert shots (single) each year for the
next 5 years. One live shot will detonate in water and one will
detonate in air. Detonation of the JASSM would occur under one of three
scenarios: (1) Detonation upon impact with the target (about 5 ft (1.5
m) above the GOM surface); (2) detonation upon impact with a barge
target at the surface of the GOM; or (3) detonation at 120 milliseconds
after contact with the surface of the GOM.
The SDB is a glide bomb. Because of its capabilities, the SDB
system is an important element of the Air Force's Global Strike Task
Force. The SDB has a range of up to 50 nm (92.6 km) and carries a
217.4-lb (98.6 kg) warhead. The SDB has approximately 48 lbs (21.7 kg)
of TNT equivalent NEW. The explosive used is AFX-757. Launch from an
aircraft would occur at altitudes greater than 15,000 ft (4572 m). The
SDB would commence a non-powered glide to the intended target. The SDB
exercise involves a maximum of six live shots a year, with two of the
shots occurring simultaneously, and a maximum of 12 inert shots, with
up to two occurring simultaneously. Detonation of the SDBs would occur
under one of two scenarios: (1) Detonation of one or two bombs upon
impact with the target (about 5 ft (1.5 m)above the GOM surface), or
(2) a height of burst (HOB) test: Detonation of one or two bombs 10 to
25 ft (3 to 7.6 m) above the GOM surface. No underwater detonations of
the SDB are planned.
The JASSM and SDBs would be launched from B-1, B-2, B-52, F-15, F-
16, F-18, or F-117 aircraft. Chase aircraft would include F-15, F-16,
and T-38 aircraft. These aircraft would follow the test items during
captive carry and free flight but would not follow either item below a
predetermined altitude as directed by Flight Safety. Other assets on
site may include an E-9 turboprop aircraft or MH-60/53 helicopters
circling around the target location. Tanker aircraft including KC-10s
and KC-135s would also be used. A second unmanned barge may also be on
location to hold instrumentation. Targets include a platform of five
containers strapped, braced, and welded together to form a single
structure and a hopper barge, typical for transportation of grain.
The proposed Eglin AFB action would occur in the northern GOM in
the EGTTR. Targets would be located in water less than 200-ft (61-m)
deep and from 15 to 24 nm (27.8 to 44.5 km) offshore, south of Santa
Rosa Island and south of Cape San Blas.
Comments and Responses
A notice of receipt of Eglin AFB's application and proposed IHA was
published in the Federal Register on April 22, 2004 (69 FR 21816). That
notice described, in detail, Eglin AFB's proposed activity, the marine
mammal species that may be affected by the activity, and the
anticipated effects on marine mammals. During the 30-day public comment
period, substantial comments were received from the Marine Mammal
Commission (Commission), the Gulf Restoration Network (GRN), and the
Acoustic Ecology Institute (AEI). Other comments received from
individuals on this proposed action only expressed either support for,
or concern over, missile launches based on a news article.
MMPA Concerns
Comment 1: The GRN has concerns that NMFS proposes to issue a 1-
year IHA, followed by a 5-year authorization to Eglin AFB. The GRN is
unclear why NMFS is presently contemplating the issuance of an IHA when
it has already stated its intention to propose regulations. The GRN
asks whether the interim action is being considered to enable Eglin AFB
and/or NMFS to complete an in-depth environmental analysis of the
potential long-term impacts of the activity prior to making a final
decision on the regulations. Alternatively, GRN asks, is this an
attempt to essentially allow Eglin AFB a 6-year LOA, which GRN believes
would be impermissible under the MMPA?
Response: NMFS proposes to issue a 1-year IHA to Eglin AFB for its
activities over the next 12 months. Subsequent authorizations will
likely proceed under section 101(a)(5)(A) of the MMPA, which allows for
take authorizations over a 5-year time horizon. The alternative to
issuance of Letters of Authorization (LOAs) under section 101(a)(5)(A)
regulations would be to continue processing applications under section
101(a)(5)(D) of the MMPA, and, presumably, issue IHAs annually to Eglin
for PSW activities. Either way, the public would be provided another
opportunity to comment on Eglin AFB's application and NMFS' proposed
action. We disagree that it is not permissible to follow a one-year IHA
with a 5-year rule and regulations that govern take authorizations. The
MMPA does not limit the number of times or the period of time over
which an applicant can receive an incidental take authorization so long
as all the requirements are met. For our determination under the
National Environmental Policy Act (NEPA), see that section later in
this document.
Comment 2: The Commission notes that the proposed weapons test
appear to fit within the definition of a ``military readiness
activity'' as defined in section 315(f) of Public Law 107-314, which
includes ``the adequate and realistic testing of military equipment,
vehicles, weapons, and sensors for proper operation and suitability for
combat use.'' As such, the revised definition of harassment adopted in
the NDAA (Public Law 108-136) would seem to be applicable in this
instance. However, NMFS' analysis of the small take request does not
seem to have employed this definition. If NMFS' preliminary conclusion
that no take by serious injury and/or death is anticipated, and the
potential for temporary or permanent hearing impairment is low and will
be avoided through the incorporation of (proposed) mitigation measures
is correct, it may be that no taking by harassment can be expected and
that no authorization is needed. The Commission therefore recommends
that NMFS analyze the request for an IHA and the small take regulations
being contemplated in light of the applicable definition of the term
``harassment.'' Although the Commission appreciates NMFS has yet to
promulgate regulations or take other steps to implement the new
definition, the statutory change cannot be ignored.
Response: In the preamble to the notice of proposed authorization
and in this document, NMFS cited the NDAA definition of Level B
harassment for military readiness activities. While NMFS believes that
the monitoring to be implemented by Eglin AFB will ensure that the
probability of Level A harassment will be very low (1-2 animals/year-
see Table 4) and mortality likely to be zero (see Table 3), an
authorization under section 101(a)(5) of the MMPA is warranted because
some animals may be harassed if the mitigation and monitoring overlooks
an animal.
Given the scientific uncertainty associated with predicting animal
presence and behavior in the field, NMFS accords some deference to
applicants requesting an MMPA authorization for an activity that might
fall slightly below the NDAA definition of harassment, so that they are
covered for impacts that may rise to the level of take. Equally
important, such an authorization also carries with it responsibilities
to implement mitigation
[[Page 48677]]
and monitoring measures to protect marine mammals.
Marine Mammal Impact Concerns
Comment 3: The GRN is concerned with Eglin AFB's and/or NMFS' claim
that the activity will only result in Level B harassment. The record
before the agency clearly establishes the potential for injury (Level A
harassment) or even death among marine mammals as a result of this
testing.
Response: Neither Eglin AFB nor NMFS have claimed that there is no
potential for incidental injury to occur as a result of this activity.
While the application calculated that 6-7 marine mammals may incur a
Level A (injury) harassment, recalculation of the potential for injury
has resulted in a revised estimate of 1-2 animals annually. Also the
criterion for mortality is lung hemorrhage calculated for a small
dolphin calf at 31 psi-msec. For the PSW, the zone of potential
lethality is approximately 75-320 m (246-1050 ft) around the detonation
point (Table 2). Table 3 provides a risk analysis that indicates that
less than 1 cetacean might be killed annually even if no mitigation
measures were implemented. However, NMFS believes that due to the
mitigation measures that Eglin AFB will implement, it is very unlikely
that any cetaceans will be killed, and injury is also unlikely as a
result of PSW activities.
Comment 4: The GRN notes that the Federal Register notice states
that from 3 to as many as 103 cetaceans would potentially be exposed
annually to 182 dB by the action and GRN contends that the impact of
the action would therefore be more than negligible and would not be an
appropriate subject of an IHA. The GRN disagrees with NMFS' claim that
exposure to sound levels greater than 182 dB on possibly 13 percent of
the GOM cetaceans would constitute only non-injurious Level B
harassment.
Response: Neither Eglin AFB nor NMFS claim that 13 percent of the
GOM cetacean population might be affected by Eglin's PSW activities. As
shown in the proposed authorization notice (69 FR 21816, April 22,
2004), only four of the 29 species/stocks of marine mammals that
inhabit the GOM would be within the area offshore Eglin AFB. Of the
high estimate of 103 cetaceans that might be subject to sound exposure
levels (SELs) of 182 dB re 1 microPa\2\-s or higher, roughly half would
be bottlenose dolphins and half would be Atlantic spotted dolphins. No
more than a single Kogia individual might be subject to an SEL of 182
dB re 1 microPa2-s. As a result of an error in estimating the number of
shots, those numbers in the application were higher than currently
projected and analyzed in this document.
The rationale on why exposure to an SEL of this magnitude would
result in only Level B harassment takes (by TTS) and why these takings
would have only negligible impacts was discussed in the proposed IHA
authorization Federal Register notice with reference to the scientific
basis for that reasoning. That information is also provided in detail
later in this document. To assess impacts on marine mammals from
explosives, NMFS and Eglin used the energy flux density (EFD) metric.
This is also explained in the proposed IHA notice and later in this
document.
Comment 5: Citing from the Minerals Management Service's 2002 Draft
Programmatic EA for GOM seismic activities, the GRN notes that a
received sound pressure level of 180 dB re 1 micro Pa (rms) or greater
is an indication of potential concern about temporary and/or permanent
injury (to cetaceans, such as sperm whales). Thus, GRN believes, there
is significant uncertainty as to whether Level A harassment would be
limited to ``nearly 3 cetaceans'' or could instead affect 103
cetaceans. In the face of this uncertainty, the GRN would contend that
the no action alternative is appropriate.
Response: The principal metric employed for determining harassment,
injury and mortality in this action is EFD, not sound pressure levels.
The scientific basis for employing this metric is explained in detail
in Eglin's application and later in this document. Use of the energy
metric has been employed in the shock trials of the USS SEAWOLF (see 63
FR 66069, December 1, 1998) and USS WINSTON S. CHURCHILL (66 FR 22450,
May 4, 2001).
Comment 6: The Commission remains concerned that NMFS continues to
categorize temporary threshold shift (TTS) as constituting Level B
harassment, discounting the potential that diminishment of hearing
capability in marine mammals, even if only of limited duration, may
cause impairment that could lead to injury or even death (e.g. by
lowering the ability of an animal to detect and avoid predators or
ships). The Commission notes, however, that regardless of whether TTS
is considered Level A or Level B harassment, taking could be authorized
under a section 101(a)(5)(D) IHA, provided that mortalities do not
occur.
Response: As mentioned in previous Federal Register documents,
second level impacts due to a marine mammal having a temporary hearing
impairment cannot be predicted and are, therefore, speculative. The
principal reason that second level impacts are not considered in
classification is that any Level B disruption of behavior could, with
suppositions, be seen as potentially dangerous and, therefore,
considered potential Level A harassment or even lethal. Similarly,
Level A injuries could be seen as being accompanied by some disruption
of behavior and, therefore, with both Level B disturbances and Level A
injuries. Such reasoning blurs the distinctions between the definitions
of harassment. NMFS believes that Level B harassment, if of sufficient
degree and duration, can be very serious and require consideration, as
has been done here. Moderate TTS does not necessarily mean that the
animal cannot hear, only that its threshold of hearing is raised above
its normal level. The extent of time that this impairment remains is
dependent upon the amount of initial TS, which depends on the strength
of the received sound and whether the TTS is in a frequency range that
the animal depends on for receiving cues that would benefit survival.
It should be noted that increased ambient noise levels, due to
biologics, storms, shipping, and tectonic events may also result in
short-term decreases in an animal's ability to hear normally. NMFS
scientists believe that marine mammals have likely adopted behavioral
responses, such as decreased spatial separation, slower swimming
speeds, and cessation of socialization to compensate for increased
ambient noise or hearing threshold levels.
Ship strikes of whales by large vessels suggest that at least
certain species of large whales do not use vessel sounds to avoid
interactions. Also, there is no indication that smaller whales and
dolphins with TTS would modify behavior significantly enough to be
struck by an approaching vessel. Finally, a hypothesis that marine
mammals would be subject to increased predation presumes that the
predators would either not be similarly affected by the detonation or
would travel from areas outside the impact zone, indicating recognition
between the signal of a single detonation at distance and potentially
debilitated food sources. Therefore, NMFS does not believe the evidence
warrants that all (or an unknown percentage) of the estimated numbers
of Level B harassment be considered as Level A harassment or as
potential mortalities.
Comment 7: The Commission states that NMFS seems to discount
entirely the possibility that marine mammals may be harassed through
changes in behavioral patterns other than by TTS.
[[Page 48678]]
The basis for this conclusion is not clear from the discussion on page
21819 of the Federal Register notice. Additional explanation is needed
and should consider, among other things, whether marine mammals might
alter their use patterns in the vicinity of detonations, or even
abandon an area, as a result of infrequent or even a one-time exposure.
Response: NMFS does not have information to support the
Commission's hypothesis that marine mammals would abandon or
significantly alter their natural behavioral patterns in response to a
single explosive detonation. Contrary to this hypothesis, NMFS believes
that, unless the mammal was transiting the area, it is unlikely that a
marine mammal would leave an area that provides important biological
resources for sustenance and reproductive success from the sounds from
a single distant water detonation (presuming here that it is more
likely that an animal will spend the majority of its time in a
biologically important area). In fact, the GOM has thousands of
lightning strikes annually (approximately 10 strikes per sq km per year
in the GOM with source levels of about 260 dB re 1 microPa (peak)(NASA,
2005). It is likely that marine mammals are evolutionarily adapted to
natural events such as tectonics and lightning storms, which have
similar characteristics to the explosives in this action. In the
absence of additional information, NMFS concludes that a marine mammal
may be startled by the received sound level from a single explosive
detonation if near enough to the source, but it is highly unlikely that
marine mammals would abandon or significantly alter their behavior
patterns. Therefore, we do not believe effects rise to the level of a
significant alteration or abandonment of natural behavioral patterns,
i.e., Level B harassment. In any case, Level B takes are counted
insofar as we consider TTS to be Level B harassment.
Comment 8: The Commission believes that NMFS needs to provide a
better explanation of, and justification for, using the dual criteria
established for determining non-lethal injury (i.e., the onset of
slight lung hemorrhage and a 50 percent probability for eardrum
rupture).
Response: Explanation and justification were provided in detail in
both the SEAWOLF and CHURCHILL Final EISs (DoN 1998 and DoN 2001). An
updated summary for using the dual injury criteria from those documents
is provided here:
1. Auditory System Injury
Tympanic membrane (TM) rupture, while not necessarily a serious or
life-threatening injury, is a useful index of injury that is well
correlated with measures of permanent hearing loss (Ketten, 1995,
1998). The occurrence of 50 percent TM rupture has been correlated to
30 percent permanent threshold shift (PTS) (Ketten, 1995, 1998) and
will be considered as the index for permanent auditory system injury.
In this response, the criteria will be explained for conservatively
estimating the range for occurrence of 50-percent TM rupture (30-
percent PTS). Significant occurrence of TM rupture would be expected at
``near field'' ranges significantly closer to the charge than the
ranges for TTS and onset of PTS. For the CHURCHILL EIS injury model, TM
rupture criteria were based on a limited number of small charge
underwater explosion tests conducted with small terrestrial mammals as
reported by both Yelverton et al. (1973) and Richmond et al. (1973). TM
rupture-specific tests were conducted with post-mortem dogs (nominal
25-kg body mass) using 1-lb (0.45-kg) TNT charges. Additional TM
rupture data from general injury tests conducted with sheep (nominal
40-kg body mass) using 0.5-lb and 1-lb (0.23-kg and 0.45-kg) pentolite
charges were also included.
Damage to terrestrial mammal internal organs typically has been
referenced to total shock wave impulse (pressure integrated over time)
(Richmond et al. (1973) and Yelverton et al. (1973)). Yelverton et al.
(1973) state that eardrum ruptures would occur at sub-lethal impulses
of 20 to 40-psi-msec (138 to 276-Pa-sec) and that an impulse of 10-psi-
msec (69-Pa-sec) or less would not cause eardrum ruptures.
Acoustic energy (proportional to the square of pressure integrated
over time) may be one of the appropriate parameters for evaluation of
the response of the mammalian ear to the intensities of underwater
noise at least sufficient to cause TTS. The shock wave's EFD appears to
be at least as good an indicator/predictor of auditory system injury
(TM rupture) as impulse and, for the CHURCHILL shock trial conditions,
provided a means to include the potential effects of the bottom-
reflected pressure wave.
Logarithmic interpolation of the test data for EFDs for 42 percent
and 67 percent TM rupture indicates that the calculated EFD required
for the occurrence of 50 percent TM rupture (approximately 30 percent
PTS) is 1.17 in-lb/in2 (20.44 milli-Joules/cm\2\). The small sample
sizes for the reported terrestrial animal test data in combination with
the inherent variability in the occurrence of TM rupture at levels less
than approximately 50 percent preclude realistic predictions of low
percentages of occurrence of TM rupture.
2. Onset of Slight Lung Injury
Using data from tests with small terrestrial mammals from Yelverton
et al. (1973) and Richmond et al. (1973), Goertner (1982) developed a
conservative model for calculating the ranges for occurrence of two
types of internal organ injury to marine mammals exposed to underwater
explosion shock waves. The two injury mechanisms considered are (1)
slight lung hemorrhage, and (2) contusions and hemorrhage of the
gastrointestinal (G.I.) tract. For lung hemorrhage, the Goertner model
considers lung volume as a function of animal weight and depth and
considers shock wave duration and impulse tolerance as a function of
animal weight and depth. Goertner indicated that slight injury to the
G.I. tract could be related to the magnitude of the peak shock wave
pressure over the hydrostatic pressure and would be independent of
mammal size and weight. Slight contusions to the G.I. tract occurred
during small charge tests (Richmond et al., 1973) when the peak shock
wave pressure was 104 psi above hydrostatic pressure. Onset of G.I.
tract contusion and onset of slight lung hemorrhage are injuries from
which a mammal would be expected to recover on its own and would not be
debilitating. For small mammals, significant G.I. tract injury (G.I.
tract hemorrhage) would be expected to occur at ranges significantly
closer to the explosion than the maximum calculated ranges for the
onset of slight lung injury. Injury ranges determined on the basis of
the Goertner model are most appropriate for use in regions close to the
explosive charge.
After correcting for the atmospheric and hydrostatic pressures for
the data, the minimum impulse (I) for predicting onset of slight lung
hemorrhage in a small mammal is:
I = 19.7 (M/42)1/3 psi-msec, or
I = 136 (M/42)1/3 Pa-sec,
where M is the body mass (in kg) of the subject animal. Impulse
values from the above equation provide a shallow depth ``starting
point'' for determining the maximum range and the corresponding ``at-
depth'' impulse level for the specific charge weight and marine mammal
size. A maximum range should not be calculated using only the above
impulse/body mass relationship
[[Page 48679]]
and the total impulse similitude equation for a specific explosive.
The modified Goertner model is very sensitive to mammal weight. By
assuming a small mammal weight for an impact analysis, the onset of
slight injury range is maximized for conservatism. Injuries from
explosions in relatively shallow water (i.e., on the continental shelf)
may be exacerbated by strong bottom-reflected pressure pulses.
Comment 9: In reviewing NMFS' May 4, 2001, response to the
Commission's January 26, 2001, comments (see 66 FR 22456, May 4, 2001),
NMFS appears to agree with the Commission that eardrum rupture is a
questionable measure of acoustic injury in marine mammals. NMFS notes
that ``(b)ecause the criterion is based upon land mammals rather than
marine mammals, and because TM (tympanic membrane) rupture research has
not been conducted on marine mammals, it is not the 50-percent rupture
itself that is the criterion used, but the 'impulse' in psi-msec that
is associated with other impacts on the body...the EFD that causes
either the 50 percent TM rupture or the impulse that causes slight lung
hemorrhage is the real criterion.'' NMFS' response further indicates
that ``because the impulse estimated to cause slight lung hemorrhage
was more conservative (i.e., had a greater range), it is slight lung
hemorrhage that is the defining criterion used for determining injury
in this action, not the EFD used for 50-percent TM rupture.'' Based on
this explanation, it appears that the 50 percent probability for
eardrum rupture is not a useful metric in that it cannot be measured.
In essence, the probability for eardrum rupture substitutes for another
metric (PTS), which also cannot be measured. Because of these
difficulties, neither metric is ultimately used in setting the safety
zone.
Response: Although non-lethal impact cannot be measured for wild
animals at the time of the action, acoustic thresholds for injury have
been derived from tests on terrestrial animals in water. These
thresholds are the best science available today. For the subject
action, the impact range determined from the lung injury threshold is
the most conservative. However, in other actions, the eardrum rupture
threshold may be more conservative. For that reason, the dual criteria
are needed to use a conservative approach for determining injury ranges
for the variety of explosive activities considered by NMFS for
incidental take authorizations.
Comment 10: Related to the previous comment, the Commission notes
that both the May 4, 2001, and the April 22, 2004, Federal Register
notices give a value of EFD that would cause 50 percent probability of
TM rupture, but provide no reference for this value and no indication
of the signal waveform or the time interval over which the energy
density flux is integrated. Before using this value of EFD as the
threshold of Level A harassment for an authorization, the applicant or
NMFS needs to provide the waveform and integration time interval and
explain the scientific basis for this choice.
Response: Explanation and reference for the EFD value are found in
response to comment 8. The nominal source waveform at unit distance
used for the Air Force risk assessment modeling is defined as follows:
p(t) = 0 for t <0
p(t) = pmax exp (-t/t) for t > 0
where p(t) is pressure as a function of time, t. Pmax represents
peak pressure at unit distance and t is the characteristic time at unit
distance. The waveform and parameters are estimated using the
similitude formulas of Weston (1960) (see, e. g., Urick, 1983)(note
that this is the Friedlander waveform).
Consistent with NMFS' SEAWOLF and CHURCHILL rulemakings and the
Navy's NEPA analyses for those actions, no bubble pulses were included
(and are not considered important for near surface shots). The
waveforms were 'propagated' using the similitude-based peak pressures
and characteristic times as functions of distance. The propagation
model was the Navy standard CASS-GRAB model, modified to calculate
impulse response of the channel.
At range, the squared pressure for the entire set of arrivals was
integrated over time, and normalized by the scalar acoustic impedance,
to yield total energy (i.e., the integration was over the duration of
all arrivals).
Comment 11: The Commission believes that additional clarification
and justification is needed concerning the ``non-injurious behavioral
response'' threshold proposed in Table 6-1 on page 14 of the
application. The applicant suggests a level of 6 dB below TTS (i.e.,
176 dB re 1 microPa\2\-sec) as a reasonable criterion to assess
potential behavioral responses of marine mammals. However, neither the
application nor the NMFS notice provides information as to how this
number was derived. Prior to issuing the requested authorization, the
applicant or NMFS should provide additional information to support the
scientific basis for using this criterion.
Response: As noted in the proposed authorization notice, the PSW
action consists of single detonations. Based on the science used to
develop the CHURCHILL criteria, for single detonations a significant
response by a marine mammal is not expected to occur other than by TTS.
The discussion in the application and Federal Register notice is
relevant to actions involving multiple detonations. NMFS will address
comments on this threshold criterion in an applicable proposed IHA
authorization with multiple detonations.
Comment 12: The Commission notes that the Federal Register notice
for the proposed IHA states that, in its rulemaking on the CHURCHILL
ship shock testing, NMFS adopted two criteria for estimating the TTS
threshold: 182 dB and 12 psi. The notice states that the second
criterion ``was introduced to provide a more conservative safety zone
for TTS when the explosive or the animal approaches the sea surface
(for which the explosive energy is reduced but the peak pressure is
not).'' The notice states that ``for large explosives (2,000 to 10,000
lbs) and explosives/animals not too close to the surface, the TTS
impact zones for these two TTS criteria are approximately the same.
However, for small detonations, some acousticians contend that ranges
for the two TTS thresholds may be quite different, with ranges for the
peak pressure threshold several times greater than those for energy.''
NMFS notes that the applicant is endorsing an approach being developed
by the Navy for ``scaling'' the peak pressure threshold in order to
estimate more accurately the TTS for small detonations while preserving
the safety feature provided by the peak pressure threshold. The
Commission recommends that, in any authorization issued to Eglin AFB,
NMFS provide the full set of data, assumptions, and calculations
considered in its review.
Response: This issue remains under review by the Navy, the U.S. Air
Force and NMFS. Navy acousticians believe that Ketten (1995), which
summarized earlier acoustic research, does not fully support using a
12-psi peak pressure threshold for TTS for underwater explosion impacts
on marine mammals from small detonations. The original basis in Ketten
(1995) for the use of the 12-psi threshold for the SEAWOLF and
CHURCHILL actions (which were 10,000 lb (4,536 kg) detonations) is the
use of a combination of in-air and in-water peak pressure measurements
without adjustment for the medium. A re-examination of the basis for
the 12-psi threshold by Navy acousticians indicate that, for underwater
explosions of small charges, a higher threshold may
[[Page 48680]]
be warranted. This led the Navy and Eglin to suggest scaling 12 psi for
small charges, which was used in the proposed authorization notice and
analysis. Although this issue remains under review by NMFS and the Navy
for future rulemaking actions (including the upcoming PSW proposed
rule), as an interim criterion for this IHA, NMFS is adopting the
experimental findings of Finneran et al. (2002) that TTS can be induced
at a pressure level of 23 psi (at least in belugas). As explained here,
this is considered conservative since a 23 psi pressure level was below
the level that induced TTS in bottlenose dolphins.
Finneran et al. (2000; as described in Finneran et al. (2002))
conducted a study designed to measure masked TTS (MTTS) in bottlenose
dolphins and belugas exposed to single underwater impulses. This study
used an ``explosion simulator'' (ES) to generate impulsive sounds with
pressure waveforms resembling those produced by distant underwater
explosions. No substantial (i.e., 6 dB or larger) threshold shifts were
observed in any of the subjects (two bottlenose dolphins and 1 beluga)
at the highest received level produced by the ES: approximately 70 kPa
(10 psi) peak pressure, 221 dB re re 1 micro Pa peak-to-peak (pk-pk)
pressure, and 179 dB re 1 microPa\2\-s total EFD. In Finneran et al.
(2002), a watergun was substituted for the ES because it is capable of
producing impulses with higher peak pressures and total energy fluxes
than the pressure waveforms produced using the ES. It was also
preferable to other seismic sources because its impulses contain more
energy at higher frequencies, where odontocete hearing thresholds are
relatively low (i.e., more sensitive). Hearing thresholds were measured
at 0.4, 4 and 30 kHz. MTTSs of 7 and 6 dB were observed in the beluga
at 0.4 and 30 kHz, respectively, approximately 2 minutes following
exposure to single impulses with peak pressures of 160 kPa (23 psi),
pk-pk pressures of 226 dB re 1 microPa, and total EFD of 186 dB re 1
microPa\2\-s. Thresholds returned to within 2 dB of the pre-exposure
value approximately 4 minutes post exposure. No MTTS was observed in
the single bottlenose dolphin tested at the highest exposure
conditions: peak pressure of 207 kPa (30 psi), 228 dB re 1 microPa pk-
pk pressure, and 188 dB re 1 microPa\2\-s total energy flux. Therefore,
until additional scientific information is obtained, NMFS has
determined that the pressure criterion for small explosions can be
raised from 12 psi to 23 psi. At this time, NMFS believes that setting
the pressure metric at 23 psi is conservative.
It should be noted that the PSW mission includes only a single
JASSM detonation in water, all other detonations are in-air
detonations. Analyses indicate that the ranges for the 23- psi TTS
metric at depths greater than 20 ft (6.1 m) are less conservative than
the originally provided ranges for the 182-dB (re 1 microPa\2\-s) TTS
energy metric. Conversely, ranges for the 23-psi TTS metric in air and
at the 1-ft (0.3-m) water depth are more conservative than the ranges
originally provided for the 182-dB energy metric. For the PSW activity,
NMFS will use the more conservative values to determine impacts (Table
1).
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[GRAPHIC] [TIFF OMITTED] TN19AU05.008
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[[Page 48681]]
Mitigation and Monitoring Concerns
Comment 13: Based on the information contained in the application
and Federal Register notice, the Commission believes that NMFS'
preliminary determinations are reasonable, provided that the proposed
mitigation and monitoring activities are adequate to detect all marine
mammals in the vicinity of the proposed operations and sufficient to
ensure that marine mammals are not being taken in unanticipated ways or
numbers. The Commission notes however, that even under the best of
conditions and using experienced observers, there is greater than an 80
percent likelihood that small cetaceans, particularly species such as
dwarf or pygmy sperm whales, will not be observed if they are in the
vicinity of the test site. Thus, although there may be a low
probability that certain marine mammal species will be within the area
where mortalities are considered possible at the time of weapon
deployment, it is unclear that the proposed monitoring effort will be
adequate to detect them if they are present. This being the case, the
proposed monitoring activities may be insufficient to provide assurance
that marine mammals are not being exposed to sound pressures or energy
levels that could cause lethal injuries. Thus, NMFS, before issuing the
requested authorization, should further explain its rationale for
determining that the takings will only be by harassment.
Response: The monitoring effort for PSW is similar to that used in
previous ship-shock actions wherein detonations of 10,000 lbs (4536 kg)
were used without any serious injuries or mortalities being detected
during extensive follow-up monitoring. While dwarf/pygmy sperm whales
are unlikely to be in the general area and, therefore, not subject to
potential injury or mortality, past shock trial exercises considered
the detection of these species to be 50 percent by vessel observers and
10 percent by aerial observers. For the bottlenose and spotted
dolphins, detection by shipboard observers is 100 percent and aerial
observers at 50 percent giving an overall detection capability of 90
percent (DON, 1999, Appendix C). However, for safety reasons,
monitoring personnel will need to vacate the respective safety zones in
advance of detonation, as explained later in this document (see Table 6
in Mitigation). As a result, Eglin AFB and NMFS calculate an overall
monitoring effectiveness of 30 percent for all species. Table 3 in this
document indicates that the risk for a lethal take of an individual
marine mammal from all PSW exercises with a 30-percent mitigation
effectiveness is less than one animal.
There is a scientific methodology to estimate the probability of
detecting marine mammals during vessel assessment surveys, as explained
in detail in Buckland et al. (1993) and Barlow (1995). Methodology
includes several components, including the probability that the mammal
will be at the surface and potentially sightable while within visual
range of the observers, the probability that an animal at the surface
will in fact be detected, and the relationship between sighting
probability and lateral distance from the ship's trackline. One factor
providing better detection rates for Kogia spp. for this action is that
the vessel observers will be monitoring a relatively small area, not
conducting track line surveys at a high rate of speed as done in NMFS
marine mammal abundance surveys. In addition, Eglin will be conducting
aerial marine mammal surveys over an area of 12.56 nm\2\ (2-nm (3.7-km)
radius), further precluding animals from entering the safety zone
undetected. As a result of all of these factors, NMFS is confident that
no marine mammals will be killed as a result of Eglin's PSW activities.
Comment 14: The Commission recommends that, if NMFS determines that
the potential for lethal injuries is sufficiently remote to warrant the
issuance of an authorization under section 101(a)(5)(D) of the MMPA,
any such authorization explicitly require that operations be suspended
immediately if a dead or seriously injured animal is found in the
vicinity of the test site, pending authorization to proceed or issuance
of regulations authorizing such takes under section 101(a)(5)(A) of the
MMPA.
Response: Testing consists of a single exercise with a single
detonation with weeks or months likely between detonations. As a
result, if a seriously injured or dead marine mammal is found in the
vicinity of the test operations do not need to be ``immediately
suspended,'' but future tests will not occur until the serious injury
or mortality has been investigated as to likely cause.
Comment 15: The GRN and the AEI find that the proposed mitigation
is inadequate to protect marine species in the GOM. Both groups claim
that visual monitoring is not an effective method for detecting all
cetaceans. The GRN notes that sperm whales, for instance, are known for
their extremely long, deep-water dives. Up to 5000 ft (1524 m) dives
have been reported for periods up to 2 hours long. The animals would
not be visible to observers in either a helicopter 250 ft (76.2 m)
above the surface of the water or on board a ship, and they could
easily surface unnoticed in an area impacted by the testing. Reliance
on visual monitoring is not sufficient to adequately protect cetacean
populations in the GOM. Instead, if allowed to proceed with the
proposed activity, Eglin AFB should be required to use passive acoustic
monitoring to ensure that impacts to protect species are minimal.
Response: While sperm whales and other deep-diving marine mammals
may remain submerged for long periods of time, the proposed action
would be located in waters less than 200 ft (61 m) deep. This habitat
is not expected to be utilized by sperm whales or beaked whales. The
marine mammal species that inhabit the waters off Eglin AFB are the
bottlenose dolphin, spotted dolphin and possibly Kogia. Other than
Kogia, these species are easily sighted from aircraft and ships. While
Kogia are more difficult to see, restricting exercises to sea states
lower than 4, having aerial coverage in addition to shipboard
observers, and the small zone for Level A harassment, should eliminate
the likelihood that Kogia or other marine mammal species would be
injured or killed. Therefore, requiring the use of passive acoustics is
not warranted.
Comment 16: The GRN is also concerned by Eglin AFB's apparent
emphasis on post-mission monitoring (affording 2 hours of aerial
surveys after the activity and only one hour of continuous aerial
surveying prior to detonation of the weapons). The GRN believes that,
although post-mission monitoring is important, major emphasis should be
placed on preventing harm, not quantifying the number of dead and
injured marine mammals and sea turtles.
Response: NMFS believes that both pre-detonation monitoring and
post-detonation monitoring are important. Eglin will begin vessel
surveys 5 hours prior to the test and aerial surveys of the test site 2
hours prior to the proposed time of detonation (Eglin, 2004). For
safety reasons, aircraft and ships will need to begin exiting the area
15 minutes prior to detonation (see Table 6). While it is very unlikely
that marine mammals will enter the relatively small impact zone between
the time vacating the area and the time of detonation, post monitoring
will provide valuable information on whether current mitigation
measures are fully effective at preventing mortality and serious
injury.
Comment 17: The AEI believes that NMFS should consider the use of
active
[[Page 48682]]
acoustic systems (i.e., fish-finding sonar) to identify large schools
of fish and/or individual sea turtles that may be affected by the
bombing exercises.
Response: Large fish schools and sea turtles will be more
effectively sighted by the marine mammal monitoring aircraft than by
standard ``fish finding'' sonars. However, to the extent that the
monitoring vessel can utilize its acoustic equipment to detect fish
schools and sea turtles, NMFS recommends that it do so. This acoustic
equipment is of low intensity and, therefore, is not expected to result
in marine mammal harassment. However, the use of more sophisticated
high-intensity military sonars are not recommended for use as a
mitigation/monitoring tool here because of its potential impacts to
marine mammals and other marine life.
Comment 18: The AEI notes that the recent calibration test for
Lamont-Doherty Earth Observatory's marine seismic array in the GOM
indicates that in relatively shallow water, loud low-frequency acoustic
sources may lead to received levels of concern at greater distances
than current models would suggest. As a result, received level models
of the bombing exercises should be based at least on the most recent
propagation models. Also, the most reliable safety radii would be
determined by real-world tests in the areas planned for the exercises.
Response: The model employed by L-DEO for seismic arrays is
different from the model used by Eglin and the Navy for explosives. The
subject risk assessment employs the CASS/GRAB Navy Standard propagation
model and Navy Standard environmental databases (including bathymetry,
sound speed, and 15-parameter geo-acoustic sediment properties). These
are considered state of the art. The propagation model starts with
impulse response and accounts for multipath propagation in the water
column and in the sediments. Hence, it estimates the effects of the
'bottom' in shallow water. For sediments like those found at the
coastal water sites for Eglin's risk assessment, propagation of sound
energy at the lower frequencies (below several hundred Hertz) is
generally much better than that in deep water. This enhanced
propagation for energy metrics is included in the range estimates for
the risk assessment.
It should be noted that sound propagation in shallow water has been
a topic of intense study and measurement for at least 50 years,
primarily by the U.S. Navy, but also by other nations and international
bodies. Shallow-water bottom effects('reverberant' multipaths, shallow
water waveguides, low-frequency cutoff, influence of sea state, etc.)
are all covered in most basic underwater-acoustics textbooks (e.g.,
Urick, 1967).
Comment 19: The GRN questions whether post-activity monitoring,
when limited to 2 hours, can accurately estimate the effectiveness of
pre-activity monitoring. While many dead marine mammals and sea turtles
may rise to the surface immediately after the mission, it is possible
that the lethal impacts of the activity may not be immediate. As a
result, sea turtles and marine mammals may resurface days later, float
to shore, and may or may not be reported to a stranding network.
Response: Considering the extensive pre-mission mitigation measures
implemented to prevent injury or mortality, NMFS believes it is
unnecessary to remain at the site with vessels and aircraft for longer
periods of time after completion of a test. Eglin AFB will coordinate
its activities with the NMFS stranding network and with local stranding
networks to locate any stranded marine mammals after an event. In
addition, Eglin AFB maintains its own stranding network team. Stranding
events are tracked by year, season and NMFS statistical zone, both
Gulf-wide and along the coastline of Eglin AFB.
Activity Concerns
Comment 20: The GRN notes that in the event that a live warhead
fails to explode during the strike, Eglin AFB will likely detonate the
warhead where it fell to the bottom of the ocean. An underwater
detonation creates a much larger chance of injury or death to all
marine species, yet Eglin does not provide an adequate description of
the level of potential impact to protected species taken under that
scenario.
Response: The noise analysis was conservatively modeled by Eglin
for 20 ft (6 m) below the surface in order to cover any water depth,
including detonation on the sea bottom. There would be no difference in
the noise zone of influence from what is modeled and mitigated from a
20-ft (6 m) depth detonation and a bottom detonation. However, the
missile itself is programmed to lose power and will not detonate after
15 minutes. Therefore, it is safe to retrieve the missile after 15
minutes and they do not need to be detonated on-site.
Description of Marine Mammals Affected by the Activity
There are 29 species of marine mammals documented as occurring in
Federal waters of the GOM. Information on those species that may be
impacted by this activity are discussed in the Eglin AFB application
and the Draft EA. A summary of that information is provided in this
section.
General information on these species can be found in Wursig et al.
(2000. The Marine Mammals of the Gulf of Mexico, TAMU Press, College
Station, TX) and in the NMFS Stock Assessment Reports (Waring, 2002).
This latter document is available at: https://www.nmfs.noaa.gov/prot_
res/PR2/Stock_Assessment_Program/sars.html#Stock Assessment Reports
Marine mammal species that potentially occur within the EGTTR
include several species of cetaceans and one sirenian, the West Indian
manatee. During winter months, manatee distribution in the GOM is
generally confined to southern Florida. During summer months, a few may
migrate north as far as Louisiana. However, manatees primarily inhabit
coastal and inshore waters and rarely venture offshore. PSW missions
would be conducted offshore. Therefore, effects on manatees are
considered very unlikely.
Cetacean abundance estimates for the study area are derived from
GulfCet II (Davis et al., 2000) aerial surveys of the continental shelf
within the Minerals Management Service Eastern Planning Area, an area
of 70,470 km\2\. Texas A&M University and NMFS conducted these surveys
from 1996 to 1998. Abundance and density data from the aerial survey
portion of the survey best reflect the occurrence of cetaceans within
the EGTTR, given that the survey area overlaps approximately one-third
of the EGTTR and nearly the entire continental shelf region of the
EGTTR where military activity is highest. The GulfCet II aerial surveys
identified different density estimates of marine mammals for the shelf
and slope geographic locations. Only the shelf data is used because PSW
missions will only be conducted on the shelf.
In order to maximize species conservation and protection, the
species density estimate data were adjusted to reflect more realistic
encounters of these animals in their natural environment. Refer to
``Conservative Estimates of Marine Mammal Densities'' in this document
and Eglin AFB's application for more information on density estimates.
A brief description of each marine mammal species observed during
GulfCet II aerial surveys on the shelf that has the potential to be
present in the PSW test area is summarized here.
[[Page 48683]]
Atlantic Bottlenose Dolphins (Tursiops truncatus)
Bottlenose dolphins are distributed worldwide in tropical and
temperate waters. In the GOM, several coastal and offshore stocks have
been identified (see Waring et al. 2002) and one stock occurs in the
inshore waters of the entire GOM. Waring et al. (2002) provides the
following minimum population estimates for the GOM bottlenose dolphin
stocks: outer shelf, 43,233; shelf and slope, 4,530; western Gulf,
2,938; northern Gulf, 3,518; eastern Gulf, 8,953; and Bay, Sound &
Estuarine waters, 3,933. Baumgartner et al. (2001) suggest a bimodal
distribution in the northern GOM, with a shelf population occurring out
to the 150-m (492 ft) isobath and a shelf break population out to the
750-m (2461 ft) isobath. Occurrence in water with depth greater than
1,000 m (3281 ft) is not considered likely. Migratory patterns from
inshore to offshore are likely associated with the movements of prey
rather than a preference for a particular habitat characteristic (such
as surface water temperature) (Ridgeway, 1972; Irving, 1973; Jefferson
et al., 1992).
The average herd or group size of Atlantic bottlenose dolphins in
shelf and slope waters was approximately four and 10 individuals,
respectively, per herd as determined by GulfCet II surveys of eastern
Gulf waters (Davis et al., 2000). The diet of Atlantic bottlenose
dolphins consists mainly of fish, crabs, squid, and shrimp (Caldwell
and Caldwell, 1983).
Atlantic Spotted Dolphins (Stenella frontalis)
Atlantic spotted dolphins are endemic to the tropical and warm
temperate Atlantic Ocean. This species ranges from the latitude of Cape
May, NJ, along mainland shores to Venezuela, including the GOM and
Lesser Antilles (Caldwell and Caldwell, 1983). Sightings of this
species are concentrated along the continental shelf and shelf edge
(Fritts et al., 1983), but they also occur farther offshore. At one
time, Atlantic spotted dolphins were considered to be the most abundant
species of dolphin in offshore waters (Schmidly, 1981), with most
sightings occurring at an average of 168 km (90.7 nm) offshore. The
best available abundance estimate for this species in the northern GOM
is the combined estimate of abundance for both the OCS (39,307,
CV=0.31) and oceanic (238, CV=0.87) waters from 1996 to 2001, which is
39,545 (CV=0.31)(NMFS, 2003).
The preferred depth of the spotted dolphin is believed to be
associated with food availability and water temperature. The diet of
the Atlantic spotted dolphin consists of squid and fish.
Dwarf Sperm Whales and Pygmy Sperm Whales
Dwarf sperm whales (Kogia simus) commonly inhabit the deeper
offshore water, generally eating squid, crustaceans, and fish (Caldwell
and Caldwell, 1983), but they do move into inshore waters during
calving season. The pygmy sperm whale (Kogia breviceps) has a diet
similar to that of the dwarf sperm whale. Both pygmy and dwarf sperm
whales have been sighted in the northern GOM primarily along the
continental shelf edge and in deeper shelf waters during all seasons
except winter (Mullin et al., 1994). The estimate of abundance for
dwarf and pygmy sperm whales in oceanic waters is 809 (CV=0.33)(Mullin
and Fulling, in prep), which is the best available abundance estimate
for these species in the northern GOM. Separate estimates of abundance
cannot be made due to uncertainty of species identification (NMFS,
2003). Dwarf and pygmy sperm whales have a high percentage of
strandings relative to percent population of all cetaceans (Mullin et
al., 1994).
Impacts to Marine Mammals
Potential impacts to marine mammals from the detonation of the PSWs
and SDBs include both lethal and non-lethal injury, as well as Level B
behavioral harassment. Although unlikely due to the extensive
mitigation measures proposed by Eglin AFB, marine mammals have the
potential to be killed or injured as a result of a blast due to the
response of air cavities in the body, such as the lungs and bubbles in
the intestines. Effects are likely to be most severe in near surface
waters where the reflected shock wave creates a region of negative
pressure called ``cavitation.'' This is a region of near total physical
trauma within which no animals would be expected to survive. A second
criterion used by NMFS for categorizing taking by mortality is the
onset of extensive lung hemorrhage. Extensive lung hemorrhage is
considered to be debilitating and thereby potentially fatal.
Suffocation caused by lung hemorrhage is likely to be the major cause
of marine mammal death from underwater shock waves.
For the acoustic analysis, the exploding charge is characterized as
a point source. The impact thresholds used for marine mammals relate to
potential effects on hearing from underwater noise from detonations.
For the explosives in question, actual detonation heights would range
from 0 to 25 ft (7.6 m) above the water surface. Detonation depths
would range from 0 to 80 ft (73.2 m) below the surface. To bracket the
range of possibilities, detonation scenarios just above and below the
surface were used to analyze bombs set to detonate on contact with the
target barge. Potentially, the barge may interact with the propagation
of noise into the water. However, barge effects on the propagation of
noise into the water column cannot be determined without in-water noise
monitoring at the time of detonation.
Potential exposure of a sensitive species to detonation noise could
theoretically occur at the surface or at any number of depths with
differing consequences. As a conservative measure a mid-depth scenario
was selected to ensure the greatest direct path for the harassment
ranges, and to give the greatest impact range for the injury
thresholds.
Explosive Criteria and Thresholds for Impact of Noise on Marine Mammals
Criteria and thresholds that are the basis of the analysis of PSW
noise impacts to cetaceans were initially used in U.S. Navy's
environmental impact statements (EISs) for ship shock trials of the
SEAWOLF submarine and the USS WINSTON S. CHURCHILL vessel (DON, 1998;
DON, 2001) and accepted by NMFS as representing the best science
available (see 66 FR 22450, May 4, 2001). With a single exception
mentioned in this document, NMFS believes that the criteria developed
for the shock trials represent the best science available. The
following sections summarize the information contained in those
actions.
Criteria and Thresholds: Lethality
The criterion for mortality for marine mammals used in the
CHURCHILL Final EIS is 'onset of severe lung injury.' This is
conservative in that it corresponds to a 1 percent chance of mortal
injury, and yet any animal experiencing onset severe lung injury is
counted as a lethal take. The threshold is stated in terms of the
Goertner (1982) modified positive impulse with value ``indexed to 31
psi-ms.'' Since the Goertner approach depends on propagation, source/
animal depths, and animal mass in a complex way, the actual impulse
value corresponding to the 31-psi-ms index is a complicated
calculation. The acoustic threshold is derived from:
I1% = 42.9 (M/34)\1/3\ psi-ms,
[[Page 48684]]
where M is animal mass in kg. Again, to be conservative, CHURCHILL
used the mass of a calf dolphin (at 12.2 kg), so that the threshold
index is 30.5 psi-ms.
Criteria and Thresholds: Injury (Level A Harassment)
Non-lethal injurious impacts are defined in this document as
eardrum rupture (i.e., tympanic-membrane (TM) rupture) and the onset of
slight lung injury. These are considered indicative of the onset of
injury. The threshold for TM rupture corresponds to a 50 percent rate
of rupture (i.e., 50 percent of animals exposed to the level are
expected to suffer TM rupture); this is stated in terms of an EFD value
of 1.17 in-lb/in\2\, which is about 205 dB re 1 microPa\2\-s. (Note:
EFD is the time integral of the squared pressure divided by the
impedance in values of dB re 1 microPa\2\-s.) This recognizes that TM
rupture is not necessarily a life-threatening injury, but is a useful
index of possible injury that is well-correlated with measures of
permanent hearing impairment (e.g., Ketten (1998) indicates a 30
percent incidence of permanent threshold shift (PTS) at the same
threshold).
Criteria and Thresholds: Non-injurious Impacts (Level B Harassment)
Marine mammals may also be harassed due to noise from PSW missions
involving high explosive detonations in the EGTTR. The CHURCHILL
criterion for non-injurious harassment from detonations, as established
through NMFS' incidental take rulemaking (see 66 FR 22450, May 4,
2001), is temporary (auditory) threshold shift (TTS), which is a
slight, recoverable loss of hearing sensitivity (DoN, 2001). The
criterion for TTS used in this document is 182 dB re 1 microPa\2\-s
maximum EFD level in any 1/3-octave band at frequencies above 100 Hz
for all toothed whales (e.g., sperm whales, beaked whales, dolphins).
(Note: 1/3-octave band is the EFD in a 1/3-octave frequency band; the
1/3 octave selected is the hearing range at which the affected species'
hearing is believed to be most sensitive.) A 1/3-octave band above 10
Hz is used for impact assessments on all baleen whales, but those
species do not inhabit the affected environment of this project.
The CHURCHILL rulemaking also established a second criterion for
estimating TTS threshold: 12 psi. The appropriate application of this
second TTS criterion is currently under debate, as this 12-psi
criterion was originally established for estimating the impact of a
10,000-lb (4536-kg) explosive to be employed for the Navy's shock
trial. It was introduced to provide a more conservative safety zone for
TTS when the explosive or the animal approaches the sea surface (for
which cases the explosive energy is reduced but the peak pressure is
not).
For large explosives (2000 to 10,000 lbs (907-4536 kg)) and
explosives/animals not too close to the surface, the TTS impact zones
for these two TTS criteria are approximately the same. However, for
small detonations, some acousticians contend the ranges for the two TTS
thresholds may be quite different, with ranges for the peak pressure
threshold several times greater than those for energy. In its
application, Eglin AFB endorsed an approach, currently being developed
by the Navy, for appropriately ``scaling'' the peak pressure threshold,
in