[Federal Register Volume 67, Number 141 (Tuesday, July 23, 2002)]
[Notices]
[Pages 48145-48154]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-18592]


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DEPARTMENT OF DEFENSE

Department of the Navy


Record of Decision for Surveillance Towed Array Sensor System Low 
Frequency Active (SURTASS LFA) Sonar

AGENCY: Department of the Navy, Department of Defense.

ACTION: Notice of record of decision.

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SUMMARY: The Department of the Navy, after carefully weighing the 
operational, scientific, technical, and environmental implications of 
the alternatives considered, announces its decision to employ two 
SURTASS LFA sonar systems with certain geographical restrictions and 
monitoring mitigation designed to reduce potential adverse effects on 
the marine environment. This decision, which pertains only to the 
employment of two SURTASS LFA sonar systems (rather than the up to four 
analyzed in the Final Overseas Environmental Impact Statement and 
Environmental Impact Statement [OEIS/EIS] for SURTASS LFA Sonar), 
implements the preferred alternative, Alternative 1, identified in the 
Final OEIS/EIS for SURTASS LFA Sonar.
    Pursuant to 10 U.S.C. 5062, the Navy is required to be trained and 
equipped for prompt and sustained combat incident to operations at sea. 
To fulfill this mandate, the Navy provides credible, combat-ready naval 
forces capable of sailing anywhere, anytime, as powerful 
representatives of American sovereignty. Fleet readiness is the 
foundation of the Navy's war fighting capability, and there is a direct 
link between fleet readiness and training. For the Navy, fleet 
readiness means essential, realistic training opportunities, in both 
open-ocean and littoral environments.
    The Navy is facing existing and emerging threats from foreign naval 
forces. For example, several non-allied nations are fielding new, quiet 
submarines. New anti-ship, submarine-launched cruise missiles are also 
being introduced. When quiet submarines and anti-ship cruise missiles 
are combined, they pose a formidable threat to our sailors and Marines, 
who are called upon to project power from the sea and maintain open sea 
lanes.
    In order to successfully locate and defend against these threats, 
our sailors must train realistically with both active and passive 
sonar. In executing anti-submarine (ASW) missions, sonar is the key to 
survival for our ships and sailors. The employment of SURTASS LFA will 
enable the Navy to meet the clearly defined, real-world national 
security need for improved ASW capability by allowing Navy Fleet units 
to reliably detect quieter and harder-to-find foreign submarines 
underwater at long range, thus providing adequate time to react to and 
defend against the threat, while remaining a safe distance beyond a 
submarine's effective weapons range.

SUPPLEMENTARY INFORMATION: The text of the Record of Decision is 
provided as follows:
    The Department of the Navy (Navy), pursuant to section 102(2)(c) of 
the National Environmental Policy Act (NEPA) of 1969, 42 U.S.C. Section 
4332(2)(c); the regulations of the Council on Environmental Quality 
(CEQ) that implement NEPA procedures, 40 CFR parts 1500-1508; 32 CFR 
part 775; and Presidential Executive Order (EO) 12114 (Environmental 
Effects Abroad of Major Federal Actions), announces its decision to 
employ two SURTASS LFA sonar systems with certain geographical 
restrictions and monitoring mitigation designed to reduce potential 
adverse effects on the marine environment. This decision, which 
pertains only to the employment of two SURTASS LFA sonar systems 
(rather than the up to four analyzed in the Final Overseas 
Environmental Impact Statement and Environmental Impact Statement 
[OEIS/EIS] for SURTASS LFA Sonar), implements the preferred 
alternative, Alternative 1, identified in the Final (OEIS/EIS) for 
SURTASS LFA Sonar.

[[Page 48146]]

Background

    The U.S. and its military forces must have the ability to project 
power decisively throughout the world. A key to the ability of the U.S. 
and its military forces to project power is the protection of U.S. and 
allied forward deployed Naval units against the threat of opposing 
force submarines. Of the approximately 500 non-U.S. submarines in the 
world, 224 are operated by non-allied nations. Many of these are the 
more advanced, quieter diesel-electric submarines that present a real 
threat to U.S. and allied forces. When these units are in a defensive 
mode, that is, not required to travel great distances or at high speed, 
they have a capability nearly equal to that of a modern U.S. nuclear 
submarine. At minimal cost, this threat potential can be readily 
obtained.
    Where once the U.S. Navy could detect hostile submarines before 
they could get close enough to launch their weapons, by the 1990's this 
response time, against the quietest threat, had shrunk to mere minutes. 
To regain the needed response time and thereby protect our forces, the 
Navy embarked on an extensive research program to develop new 
technologies to detect submarines at long ranges. Among the 
technologies investigated were radar, laser, magnetic, infrared, 
electronic, electric, hydrodynamic, biologic and sonar (high-, mid- and 
low frequency). Although no single technology investigated was 
effective during all tactical and environmental conditions, the most 
effective and best available technology for reliable long-range 
detection was Low Frequency Active (LFA) sonar.
    LFA sonar is an augmentation to the passive (SURTASS) detection 
system. Under certain, specific oceanic conditions, passive sonar can 
provide the detection required. However, under environmental conditions 
found in many ocean areas, passive sonar cannot detect quiet targets. 
Therefore, passive systems alone cannot detect quiet, harder-to-find 
submarines during all conditions, particularly at long ranges.

SURTASS LFA Sonar System Description

    SURTASS LFA sonar is a long-range, all-weather sonar system that 
operates in the low frequency (LF) band between 100 and 500 Hertz (Hz). 
It has both active and passive components. The active component of the 
system, LFA, is a set of 18 low frequency acoustic transmitting source 
elements (called projectors) suspended by cable from underneath a ship. 
The source level of an individual projector is 215 dB. These projectors 
produce the active sonar signal or ``ping.'' A ``ping,'' or 
transmission, can last between 6 and 100 seconds. The time between 
transmissions is typically 6 to 15 minutes. The average duty cycle 
(ratio of sound ``on'' time to total time) is between 10 and 20 
percent. The SURTASS LFA sonar signal is not a continuous tone, but 
rather a transmission of waveforms that vary in frequency and duration. 
The duration of each continuous frequency sound transmission is 
nominally 10 seconds or less. The signals are loud at the source, but 
levels diminish rapidly over the first kilometer. The passive, or 
listening, component of the system is SURTASS, which detects returning 
echoes from submerged objects, such as threat submarines, through the 
use of hydrophones on a receiving array that is towed behind the ship. 
The SURTASS LFA ship maintains a minimum speed of 5.6 kilometers (km) 
per hour (kph) (3 knots [kt]) through the water to tow the horizontal 
line hydrophone array.

Alternatives Considered

    In preparing the OEIS/EIS the Navy considered three alternatives, 
including Alternative 1 (SURTASS LFA sonar employment [up to four 
systems] with geographic restrictions and monitoring mitigation); 
Alternative 2 (unrestricted SURTASS LFA sonar employment [up to four 
systems]); and the No Action alternative. Each alternative was 
evaluated and compared against the others in terms of fulfillment of 
the Navy's validated need for reliable detection of quieter and harder-
to-find underwater submarines at long range, and the potential for 
environmental impacts. The word ``employment'' as used in this context 
means the use of SURTASS LFA sonar during routine training and testing, 
as well as the use of the system during military operations. 
``Employment'' does not apply to the use of the system in armed 
conflict or direct combat support operations, nor during periods of 
heightened threat conditions, as determined by the National Command 
Authorities (President and Secretary of Defense or their duly 
designated alternates or successors).
    Alternative 1, which is the Navy's preferred alternative in the 
Final OEIS/EIS, involves the employment of up to four SURTASS LFA 
systems with certain geographical restrictions and monitoring 
mitigation to reduce potential adverse effects on the marine 
environment. The geographic restrictions include limiting SURTASS LFA 
sonar received levels to not exceed 145 dB at known recreational or 
commercial diving sites; limiting SURTASS LFA sonar received levels to 
below 180 dB within 22 km (12 nm) of all coastlines (including islands) 
and in areas declared as Offshore Biologically Important Areas (OBIAs); 
and the use of sound pressure level (SPL) modeling to accurately gauge 
the 145 dB and 180 dB sound fields prior to commencing operations. The 
monitoring mitigation includes visual monitoring, the use of passive 
acoustic monitoring, and use of the high frequency marine mammal 
monitoring (HF/M3) sonar to detect marine mammals entering or within 
the 180-dB sound field. (See ``Mitigation'' below for further details).
    Additionally, under this alternative, the Navy's Long Term 
Monitoring Program (budgeted at a level of $1M per year for five years, 
starting with the issuance of the first Letter of Authorization [LOA] 
by NMFS under the Marine Mammal Protection Act [MMPA]) will provide 
information to further the understanding of the potential effects of 
anthropogenic (human-generated) sounds on the marine environment.
    Alternative 2 involves the unrestricted operation of up to four 
SURTASS LFA sonar systems in the active mode. Under this alternative, 
the Navy would employ these systems with no mitigation measures (i.e., 
no geographic restrictions or monitoring mitigation to prevent 
potential effects on marine animals and divers). This alternative would 
maximize the Navy's operational flexibility and capability to employ 
SURTASS LFA sonar. However, this alternative has a higher potential to 
affect the marine environment than the other alternatives.
    Under the No Action Alternative, operational employment of SURTASS 
LFA sonar would not occur. This would foreclose employment of SURTASS 
LFA sonar technology, and severely impair the Navy's ability to train 
to locate and defend against enemy submarines. Because the fleet must 
``train as it fights,'' this would in turn directly impact Fleet 
readiness and national security. The lack of a reliable, long-range 
underwater submarine detection capability would make it possible for 
potentially hostile submarines to clandestinely place themselves into 
position to threaten U.S. and allied Fleet units and land-based 
targets. Without this long-range surveillance capability, the reaction 
times to submarines would be greatly reduced and the effectiveness of 
close-in, tactical systems to neutralize threats would be seriously, if 
not fatally, compromised. Although it is the most environmentally 
preferable alternative,

[[Page 48147]]

the No Action Alternative would not fulfill the need to improve U.S. 
detection of quieter and harder-to-find underwater submarines at long 
range.

Environmental Impacts

    The Navy analyzed the potential impacts of the employment of up to 
four SURTASS LFA sonar systems, with certain geographical restrictions 
and monitoring mitigation designed to reduce potential adverse effects 
on the marine environment, in several resource areas. Among the 
resource areas covered were impacts upon marine mammals, fish and sea 
turtles, human divers and swimmers, commercial and recreational 
fishing, whale watching and marine mammal research and exploration 
activities. This ROD summarizes the potentially significant, but 
mitigable impacts associated with the decision and the implementation 
of the selected alternative. The Navy also considered the selected 
action's potential for indirect effects and cumulative impacts, and 
ensured consistency with federal policies addressing environmental 
justice (EO 12898) and protection of children from environmental health 
and safety risks (EO 13045).
    The main areas of impact analysis concerned the potential impact of 
low frequency sounds upon marine life and human divers. The analytical 
process utilized in preparation of the OEIS/EIS first conducted a 
scientific literature review to determine data gaps. Next, scientific 
screening of marine animal species for potential sensitivity to low 
frequency underwater sound was undertaken. Following these steps, 
scientific research and the estimation of the potential for effects 
from low frequency sound on marine mammals and humans in water was 
conducted. The research on marine mammals led to the development of a 
method for quantifying risk to marine mammals. Next, underwater 
acoustic modeling was conducted. These elements combined to produce an 
estimation of marine mammal stocks potentially affected. Similar 
methodologies were used to provide estimations of potential injuries to 
fish and sea turtles. Finally, geographic restrictions and monitoring 
mitigation were established to minimize the potential for effects to a 
negligible level.
    Specifically with regard to marine mammals, the analysis of 
potential impacts contained in the OEIS/EIS was developed based on a 
literature review, the results of the Navy's Low Frequency Sound 
Scientific Research Program (LFS SRP) and underwater acoustical 
modeling. The potential impacts considered were for injury and/or 
significant change to biologically important behaviors. Biologically 
important behaviors are those related to activities essential to the 
continued existence of a species, such as feeding, migrating, breeding 
and calving.
    Initially, it was determined there was potential for injurious 
effects within short ranges from the SURTASS LFA sonar. This area was 
designated as the LFA Mitigation Zone and covers a volume of water 
ensonified to a level at or above 180 dB (sound pressure level) by the 
SURTASS LFA sonar transmit array. Under normal operating conditions, 
this zone will vary between the nominal ranges of 0.75 to 1.0 km (0.40 
to 0.54 nm) from the source array ranging over a depth of approximately 
87 to 157 m (285 to 515 ft). (The center of the array is at a nominal 
depth of 122 m [400 ft]).
    For the purposes of the SURTASS LFA sonar analyses presented in the 
Final OEIS/EIS and this ROD, all marine mammals exposed to received 
levels at or above 180 dB are evaluated as if they are injured. This 
determination was based on estimations of the range of frequencies at 
which an animal's hearing is most sensitive and the associated hearing 
thresholds (including an examination of anatomical models of inner ear 
function); extrapolation from human exposure results; comparison to 
fish hearing studies; and recent measurements of levels of temporary 
threshold shift (TTS) in marine mammals.
    For the purposes of the SURTASS LFA sonar analysis presented in the 
Final OEIS/EIS and this ROD, an animal will have to be within the 180-
dB sound field during transmission for injury to occur. The probability 
of this occurring is negligible because of the visual and acoustic 
monitoring that will be used whenever the SURTASS LFA sonar is 
transmitting. (See ``Mitigation'' below for further details.)
    Knowing that cetacean behavioral responses to low frequency sound 
signals needed to be better defined using controlled experiments, the 
Navy supported the three-year LFS SRP conducted by independent 
scientists beginning in 1997. The LFS SRP was designed to supplement 
the limited scope of data from previous studies. This field research 
program was based on a systematic process for selecting the marine 
mammal indicator species (baleen whales were used as indicator species 
for other marine animals in the studies because they are the animals 
that are the most likely to have the greatest sensitivity to low 
frequency sound, have protected status, and have shown avoidance 
responses to low frequency sounds) and field study sites, using inputs 
from several workshops involving a broad group of interested parties 
(academic scientists, federal regulators, and representatives of 
environmental and animal welfare groups). Controlled experimental tests 
were designed and conducted by independent scientists who are 
recognized experts in the fields of marine mammalogy, marine 
bioacoustics and underwater acoustics. The LFS SRP involved the 
following species and settings: Phase I--blue and fin whales feeding in 
the Southern California Bight (September-October 1997); Phase II--gray 
whales migrating past the central California coast (January 1998); and 
Phase III--male humpback whales singing off Hawaii (February-March 
1998). The LFS SRP produced new information about responses to low 
frequency sounds at received levels from 120 to 155 dB. The scientific 
team explicitly focused on situations that promoted high received 
levels, but were seldom able to achieve received levels above 155 dB 
due to the motion of the whales and maneuvering constraints of the low 
frequency source vessel. Prior to the LFS SRP, the expectation was that 
whales would begin to show avoidance responses at received levels of 
120 dB. Immediately obvious avoidance responses were expected for 
received levels greater than 140 dB. Although the LFS SRP experiments 
detected some short-term behavioral responses at estimated received 
levels between 120 and 155 dB and several behavioral responses were 
revealed through later statistical analysis, the independent scientists 
conducting the research concluded that there was no significant change 
in a biologically important behavior detected in any of the three 
phases. Most animals that did respond returned to normal baseline 
behavior within a few tens of minutes. The modeled underwater acoustic 
received levels, which were calculated in the Final OEIS/EIS subsequent 
to the LFS SRP, have demonstrated that the range of exposure levels for 
subject animals during the LFS SRP covered a significant portion of the 
received level range that will be expected during actual SURTASS LFA 
sonar operations.
    To estimate the percentage of marine mammal stocks potentially 
affected on a yearly basis under the selected alternative, the typical 
annual SURTASS LFA sonar operating schedule was correlated to 31 
acoustically modeled sites. Conservative predictions from the modeling 
of the annual estimates of percentages of marine mammal stocks 
potentially

[[Page 48148]]

affected by SURTASS LFA sonar operations in the Pacific/Indian Oceans 
and Atlantic Ocean/Mediterranean Sea are given in the Final OEIS/EIS. 
Since marine mammal stocks are reproductively isolated, decreases in 
one stock cannot be replaced by animals from other stocks. Therefore, 
to accurately assess the potential effect of SURTASS LFA sonar, each 
stock was examined independently.
    Under the selected alternative, the potential impact on any stock 
of marine mammals from injury is considered negligible, and the 
potential effect on the stock of any marine mammal from significant 
change in a biologically important behavior is considered minimal. 
However, because there is some potential for incidental takes, the Navy 
is requesting a Letter of Authorization (LOA) under the MMPA for each 
SURTASS LFA sonar system from NMFS for the taking of marine mammals 
incidental to the employment of SURTASS LFA sonar during training, 
testing and routine military operations. The Final Rule for issuance of 
the LOA for SURTASS LFA operations was published on 16 July 2002. In 
the Final Rule the National Marine Fisheries Service (NMFS) determined 
that employment of SURTASS LFA as described in Alternative 1 of the 
OEIS/EIS and implemented in this ROD will have negligible impacts on 
the species and stocks of marine mammals and will not have an 
unmitigable adverse impact on the availability of such marine mammals 
for subsistence uses. Additionally, NMFS considers the unintentional 
takes to be ``small numbers of marine mammal species or population 
stocks.''
    The Navy has also consulted with NMFS under Section 7 of the ESA 
concerning the possible incidental taking of listed species, including 
marine mammals, sea turtles, and fish. In a Biological Opinion dated 30 
May 2002, NMFS indicated that employment of the SURTASS LFA sonar as 
described by Alternative 1 of the Final OEIS/EIS and implemented by 
this ROD may adversely affect, but is not likely to jeopardize the 
continued existence of affected endangered and threatened species.
    Regarding impacts to fish, the risk of physical harm or injury from 
exposure to SURTASS LFA sonar transmissions will be no greater than 
that for marine mammals. Several factors support this finding. First, 
coastal waters, OBIAs and recreational dive sites commonly contain 
significant concentrations, abundances and diversity of fish stocks, 
and geographic restrictions imposed on the SURTASS LFA sonar system 
employment limits received levels to no greater than 145 dB at known 
recreational and commercial dive sites and below 180 dB within 22 km 
(12 nm) of any coastline and in offshore biologically important areas. 
Based on prior studies, it is reasonable to consider hearing loss or 
injury to fish from SURTASS LFA sonar transmissions to be limited to 
received levels of 180 dB and higher. Thus, areas of high fish 
abundance and diversity will not be exposed to levels of LFA sounds 
that could potentially cause injury. Second, the SURTASS LFA sonar 
signal has a narrow bandwidth (approximately 30 Hz) whereas most fish 
species have much wider hearing bandwidths, which minimizes the 
potential for masking important regions of fish hearing bandwidth. 
Third, given that the SURTASS LFA sonar ship is always moving and that 
the system has a low system duty cycle (20 percent or less), fish will 
spend little time in the LFA mitigation zone. Finally, the LFA 
mitigation zone is small relative to fisheries resource regions and 
open ocean fish habitats. In any event, because only two SURTASS LFA 
sonar systems will be employed under this ROD, any potential for 
impacts to fish is less than for the four systems analyzed in the Final 
OEIS/EIS.
    Pelagic fish are food for many marine mammals. If these prey 
species were within the 180-dB sound field of the SURTASS LFA sonar 
during source transmission (no more than 20 percent of the time), they 
could potentially be indirectly affected. However, it is unlikely that 
prey availability for marine mammals would be altered for more than a 
few hours. Based on the analyses of potential effects on fish, the 
potential for injury to fish on a stock level is negligible.
    Sea turtle encounters with SURTASS LFA sonar will be limited and 
not significant due to the same factors described above for fish. Thus, 
it is unlikely that a significant portion of any sea turtle stock will 
experience adverse effects on movements, migration patterns, breathing, 
nesting, breeding, feeding, or other normal behaviors. In any event, 
because only two SURTASS LFA sonar systems will be employed under this 
ROD, any potential for impacts to sea turtles is less than for the four 
systems analyzed in the Final OEIS/EIS. Moreover, given that sea 
turtles are comparable in size to a small marine mammal, the visual 
monitoring and active acoustic monitoring employed under the 
implemented alternative will further reduce the risk of sea turtles 
encountering the SURTASS LFA sonar system.
    Because data regarding the effects of underwater low frequency 
sound on humans were limited, the Navy conducted two scientific 
research studies to analyze the potential effects of low frequency 
sound on human divers. This research, in conjunction with guidelines 
developed from psychological aversion testing, led to the conclusion 
that low frequency sounds at or below 145 dB received level would not 
have an adverse effect on recreational or commercial divers. The Naval 
Submarine Medical Research Laboratory then established a 145-dB 
received level criterion for recreational and commercial divers, which 
has been endorsed by both the Navy's Bureau of Medicine and Surgery and 
the Naval Sea Systems Command.
    Impacts on human divers, swimmers, surfers, snorkelers, and others 
that may submerse themselves below the ocean's surface will not be 
significant. Several factors support this conclusion. First, geographic 
restrictions imposed on SURTASS LFA sonar system employment limits 
received levels to no greater than 145 dB at known recreational and 
commercial dive sites. Second, exposure to low frequency sound energy 
will be eliminated or greatly reduced at beaches that are separated 
from the open ocean by a land mass (barrier island) or beaches along a 
broad, shallow portion of the continental shelf. Third, other than for 
very short periods of time, swimmers, surfers, and snorkelers are 
located at depths not greater than 2 m (6.5 ft), where substantial 
sound transmission losses occur in the top layer of water (up to 20 dB 
less than sound fields in adjacent deeper water). Also, as noted 
earlier, only two SURTASS LFA sonar systems will be employed under this 
ROD, so any potential impacts to divers are less than for the four 
systems analyzed in the Final OEIS/EIS.
    Under the selected alternative, there will be negligible impacts on 
fish (as discussed previously) and, hence, negligible impact on 
commercial and recreational fishing in marine waters, fisheries trade, 
or related employment.
    There will be no significant impacts on whale watching activities 
as a result of the employment of SURTASS LFA sonar, primarily because 
of the geographic restrictions imposed on SURTASS LFA sonar operations, 
which are designed to avoid areas of high concentrations of marine 
mammals. Thus, operations will not occur in prime whale watching areas.
    Employment of the system and implementation of the selected 
alternative will not result in potential adverse impacts to existing

[[Page 48149]]

governmental, commercial, or academic research and exploration 
activities. SURTASS LFA sonar sound fields will not exceed 145 dB 
within known recreational and commercial dive sites, which includes 
blue water (open ocean) dive sites related to oceanic research. Many 
research and exploration activities are conducted from vessels under 
the University National Oceanographic Laboratory System (UNOLS), which 
cooperates with the Navy on a continuous basis. In addition, data from 
the Navy's proposed Long Term Monitoring Program can be used to 
supplement ongoing and future oceanographic and marine environmental 
research endeavors.
    The potential cumulative impact issue associated with SURTASS LFA 
sonar operations is the addition of underwater sound to oceanic ambient 
noise levels, which, in turn, could have impacts on marine animals. 
Analysis of the potential cumulative impacts requires a discussion of 
recent changes to ambient sound levels in the world's oceans; the 
operational parameters of the SURTASS LFA sonar system, including the 
required mitigation; and the contribution of SURTASS LFA sonar to 
oceanic noise levels relative to other human-generated sources of 
oceanic noise. As noted in the Final OEIS/EIS, since 1950 oceanic 
ambient noise levels have risen by as much as 10 dB, mostly due to 
commercial shipping. Two SURTASS LFA sonars can transmit sound into the 
ocean for a total maximum of 36 days per year'versus a total of 21.9 
million days per year for the 60,000 vessels of the world's merchant 
fleet (assuming 80 percent of the merchant ships are at sea at any one 
time). Therefore, within the existing environment, the potential for 
accumulation of noise in the ocean by the intermittent operation of 
SURTASS LFA sonars is considered negligible.
    Any cumulative impacts on fish (including sharks), sea turtle or 
marine mammal stocks from implementation of the selected alternative 
are a long-term issue, and are estimated to be extremely small because 
the system will transmit for a relatively brief period of time on an 
annual basis (estimated maximum of 432 hours per vessel per year); the 
system will operate at a low duty cycle (on no more than 20 percent of 
the time); and the system will not be stationary. In any event, because 
only two SURTASS LFA sonar systems will be employed under this ROD, any 
potential for impacts is less than for the four systems analyzed in the 
Final OEIS/EIS. Moreover, all observations made during the LFS SRP 
suggest that behavioral effects terminate when transmissions stop. 
Thus, the maximum scale on which any impacts are likely to occur is a 
nominal 30-day operational at-sea mission.

Mitigation

    All practicable means to avoid or minimize environmental harm have 
been adopted through the incorporation of mitigation measures into 
operation of the SURTASS LFA sonar. The objective of these mitigation 
measures is to avoid injury to marine mammals and sea turtles near the 
SURTASS LFA sonar source and to recreational and commercial divers in 
the marine environment. Mitigation measures involve both geographic 
restrictions and operational measures. Geographic restrictions include 
limiting the SURTASS LFA sonar-generated sound field to a maximum of 
145 dB (received level) in the vicinity of known recreational or 
commercial dive sites; limiting the SURTASS LFA sonar-generated sound 
field to below 180 dB (received level) within 22 km (12 nm) of any 
coastlines (including islands) and in offshore areas outside this zone 
that have been determined to be Offshore Biologically Important Areas 
(OBIAs); and estimating SURTASS LFA sound pressure levels prior to and 
during operations to provide the information necessary to modify 
operations, including the delay or suspension of transmissions, in 
order not to exceed the 145-dB and 180-dB sound field criteria.
    Additionally, monitoring will take place during operations to 
prevent injury to marine animals. This monitoring will take three 
forms. First, visual monitoring for marine mammals and sea turtles will 
be conducted from the vessel during daylight hours by personnel trained 
to detect and identify marine mammals and sea turtles. Monitoring will 
begin 30 minutes before sunrise for ongoing missions or 30 minutes 
before SURTASS LFA sonar is deployed and continue until 30 minutes 
after sunset or until the SURTASS LFA sonar have been recovered. 
Second, passive acoustic monitoring using the SURTASS array will listen 
for sounds generated by marine mammals as an indicator of their 
presence when SURTASS is deployed. Finally, active acoustic monitoring 
will take place using the High Frequency Marine Mammal Monitoring (HF/
M3) sonar, which is a Navy-developed, enhanced high frequency 
commercial sonar to detect, locate, and track marine mammals that may 
pass close enough to the SURTASS LFA sonar's transmit array to enter 
the 180-dB sound field (LFA mitigation zone). HF/M3 sonar monitoring 
will begin 30 minutes before the first SURTASS LFA sonar transmission 
of a given mission is scheduled to commence and continue until 
transmissions are terminated. Whenever a marine mammal or sea turtle is 
detected within the LFA mitigation zone (180-dB sound field) or within 
the 1-km buffer zone beyond the LFA mitigation zone (interim 
operational restriction per NMFS Final Rule), the Officer in Charge 
will order the immediate delay or suspension of SURTASS LFA sonar 
transmissions, until the animal is determined to have moved beyond the 
buffer zone.
    The startup of the HF/M3 sonar will involve a ramp-up from a source 
level of approximately 180 dB to ensure there is no inadvertent 
exposure of local animals to received levels 180 dB and above. If the 
operating area is found to be clear, the source level will be increased 
in 10-dB steps until full power (if required) is attained, at which 
time the operator will adjust the HF/M3 sonar controls as necessary to 
optimize system performance. The HF/M3 sonar and its operating 
protocols were designed to minimize potential effects on marine 
animals.
    The HF/M3 sonar operates with a similar power level (220 dB), 
signal type and frequency (30 to 40 kHz) as high frequency ``fish 
finder'' type sonars used worldwide by both commercial and recreational 
fishermen. The HF/M3 sonar is located near the top of the SURTASS LFA 
sonar vertical line array. Its computer terminal for data acquisition, 
processing and display is located in the SURTASS Operations Center. The 
general characteristics of the HF/M3 sonar are provided in the Final 
OEIS/EIS.
    Analysis and testing of the HF/M3 sonar operating capabilities 
indicate that this system substantially increases the probability of 
detecting marine mammals that may pass close enough to the SURTASS LFA 
sonar's transmit array to enter the 180-dB sound field (LFA mitigation 
zone) and provides excellent monitoring capability (particularly for 
medium to large marine mammals) beyond the LFA mitigation zone, in the 
1-km buffer zone. The system's ability to detect marine mammals of 
various sizes has been verified in several sea trials. Recent testing 
of the HF/M3 sonar, as documented in the Final OEIS/EIS, has 
demonstrated a probability of detection above 95 percent within the LFA 
mitigation zone for most marine mammals.

Long Term Monitoring (LTM) Program

    The LTM program consists of two parts. First are NMFS-directed 
reports

[[Page 48150]]

under the Final Rule. These reports will provide the necessary 
information for assessments of whether any taking of marine mammals 
occurred within the SURTASS LFA mitigation zone during operations based 
upon data from the monitoring mitigation (visual, passive acoustic, 
active acoustic). Data analysis from the LTM and post-operation 
acoustic modeling will provide post-mission estimates of any incidental 
harassment takes. The second part of the LTM program involves long-term 
independent scientific research efforts on topics designed to fill data 
gaps and further the overall understanding of the effects of 
anthropogenic sound and noise on the marine environment. While the Navy 
believes that the research and analyses contained in the Final OEIS/EIS 
are sufficient to permit informed decision-making regarding the 
employment of SURTASS LFA sonar, it believes that it would be prudent 
to continue research. The LTM program has been budgeted by the Navy at 
a level of $1M per year for 5 years, starting with the issuance of the 
first LOA.
    During routine operations of SURTASS LFA sonar, technical and 
environmental data will be collected and recorded. These will include 
data from visual and acoustic monitoring, ocean environmental 
measurements, and technical operational inputs. As part of the LTM 
Program and as stipulated in the MMPA Final Rule/LOA, the following 
reports are required. First, a mission report will be provided to NMFS 
on a quarterly basis with the report including all active-mode missions 
that have been completed 30 days or more prior to the date of the 
deadline for the report. Second, the Navy will submit an annual report 
to NMFS no later than 90 days prior to expiration of an LOA. Finally, 
the Navy is required to provide a final comprehensive report analyzing 
any impacts of SURTASS LFA sonar on marine mammal stocks during the 5-
year period of the regulations.

Summary of Public Involvement

    The public participation program for the OEIS/EIS began with 
publication of a Notice of Intent (NOI) to prepare an EIS in the 
Federal Register (FR) on July 18, 1996. Three public scoping meetings 
were held in August 1996 to determine the scope of issues to be 
addressed by the OEIS/EIS. In addition to conducting the public 
participation program, the Navy invited representatives of concerned 
environmental groups, or non-governmental organizations, to an outreach 
meeting held on January 8, 1997 in Washington, DC. Three additional 
meetings were held between February 1997 and June 1998. The purpose of 
these meetings was to provide interested parties with detailed 
briefings on SURTASS LFA sonar and to exchange views on the EIS process 
and content. The outreach meetings provided significant input to the 
OEIS/EIS development.
    The Navy also organized a Scientific Working Group (SWG) on ``The 
Potential Effects of Low Frequency Sound on the Marine Environment.'' 
The SWG provided a forum for scientific discourse among Navy and non-
governmental organizations to address the underlying scientific issues 
needing resolution for development of the OEIS/EIS. Group members 
included representatives from the Navy, the National Marine Fisheries 
Service, the Marine Mammal Commission, several leading universities, 
several leading marine research institutions, and an observer from the 
League for Coastal Protection, who represented the public environmental 
community. The SWG met three times and was responsible for designing 
the LFS SRP, which provided critical research on the impacts of low 
frequency sounds upon marine mammals. The results from the LFS SRP were 
key factors driving the development and conclusions of the OEIS/EIS.
    On July 31, 1999, copies of the Draft OEIS/EIS were distributed to 
agencies and officials of federal, state, and local governments, 
citizen groups and associations, and other interested parties (FR Vol. 
64 No. 146). Documents produced for the SURTASS LFA Sonar Draft OEIS/
EIS were also made available for review at 17 public libraries located 
in many coastal states, including Hawaii.
    A 90-day public review and comment period on the Draft OEIS/EIS 
ended on October 28, 1999. During this period, three public hearings 
were held on the Draft OEIS/EIS with notifications published in the 
Federal Register on September 14, 1999 (FR Vol. 64 No. 177) and in 
local newspapers. Over 1,000 comments were received on the Draft OEIS/
EIS, covering federal, state, regional, and local agencies, groups and 
associations, and private individuals. All oral and written comments 
received were considered in the preparation of the Final OEIS/EIS.
    On January 19, 2001, copies of the Final OEIS/EIS were distributed 
to agencies and officials of federal, state, and local governments, 
citizen groups and associations, and other interested parties (FR Vol. 
66 No. 23). The Final OEIS/EIS was also made available for review at 17 
public libraries located in many coastal states, including Hawaii.
    The SURTASS LFA Sonar OEIS/EIS Internet Web site (http://www.surtass-lfa-eis.com) will be available for information purposes 
until 60 days after publication of the ROD in the Federal Register.

Comments on the Final OEIS/EIS

    The Navy received eleven comment letters on the Final OEIS/EIS, 
including one comment from the U.S Environmental Protection Agency 
(USEPA), six comments from individuals, and four from non-governmental 
organizations. Comments received were considered when preparing this 
ROD.
    The USEPA in its comments on the Draft OEIS/EIS recommended that 
information from the NMFS biological opinion be included in the Final 
OEIS/EIS. As the biological opinion was not completed when the Final 
OEIS/EIS was published, in comments on the Final OEIS/EIS the USEPA 
similarly requested that the Navy clearly define the mitigation 
measures in the ROD based on the biological opinion. This information 
has been provided in this document.
    Six comment letters were received from individuals. Responses to 
issues raised in four of the letters were adequately addressed in the 
Final OEIS/EIS and/or the NMFS Final Rule. The comments of another 
individual, which primarily concerned diver issues, were addressed in 
sufficient detail in the Final OEIS/EIS and Technical Report Number 3 
(Summary Report on the Bioeffects of Low Frequency Waterborne Sound). 
The comments of Mr. K. C. Balcomb, which primarily concerned the 
Bahamas stranding and the potential for injury to marine mammals from 
resonance, have been addressed in this document under the discussion 
concerning the requests for the Navy to do a supplemental EIS and were 
addressed in the NMFS Final Rule.
    The Cape Cod Commercial Hook Fisherman's Association, Inc., raised 
concerns about impacts that active sonar will have on the New England 
groundfishery. The potential for impacts from SURTASS LFA sonar to fish 
and commercial/recreational fishing was addressed in the Final OEIS/
EIS. Under the selected alternative, there will be negligible impacts 
on commercial and recreational fishing in marine waters, fisheries 
trade, or related employment.
    The Navy received two letters from the Natural Resources Defense 
Council (NRDC) (letters of 31 May 2001 and 4 February 2002) and one 
from Earth Island Institute (EII) (letter of 27 September 2001) stating 
that since the Final SURTASS LFA Sonar OEIS/EIS

[[Page 48151]]

was published in January 2001 significant new information relevant to 
environmental concerns and bearing on the Final OEIS/EIS analysis and 
conclusions has been developed. These letters further requested that 
the Navy prepare a supplemental EIS (SEIS) based on the matters 
presented. Under CEQ regulations governing NEPA, Federal agencies are 
required to prepare an SEIS when there are significant new 
circumstances or information relevant to environmental concerns and 
bearing on the proposed action or its impacts (40 CFR 1502.9(c)(1)).
    First, the letters have suggested that there is a potential for 
non-auditory physiological impacts on marine mammals, induced by 
acoustic resonance of the LFA signal in the bodies of animals. They 
also suggest that resonance can cause serious physical injury or death 
at far lower acoustic intensities and over a much wider range of impact 
than the Navy has heretofore calculated.
    In response to the resonance issue raised by these letters and 
comments to NMFS Proposed Rule, Cudahy and Ellison (2002) analyzed the 
potential for injury related to resonance from SURTASS LFA signals. 
Their analysis does not support the claim that resonance from LFA sonar 
will cause injury. Physical injury due to resonance will not occur 
unless it will increase stress on tissue to the point of damage. 
Therefore, the issue is not whether resonance occurs in air/gas 
cavities, but whether tissue damage occurs. Cudahy and Ellison (2002) 
indicate that the potential for in vivo tissue damage to marine mammals 
from exposure to underwater low frequency sound will occur at a damage 
threshold on the order of 180 to 190 dB or higher. These include: (1) 
Transluminal (hydraulic) damage to tissues at intensities on the order 
of 190 dB or greater; (2) vascular damage thresholds from cavitation at 
intensities in the 240-dB regime; (3) tissue shear damage at 
intensities on the order of 190 dB or greater; and (4) tissue damage in 
air-filled spaces at intensities above 180 dB.
    In a workshop held April 24 and 25, 2002, an international group of 
32 scientists with backgrounds in acoustics met at NMFS Headquarters in 
Silver Spring, Maryland, to consider the question of acoustic resonance 
and its possible role in tissue damage in marine mammals. The group 
concluded that it is not likely that acoustic resonance in air spaces 
plays a primary role in tissue damage in marine mammals exposed to 
intense acoustic sources. Tissue displacements are too small to cause 
damage, and the resonant frequencies of marine mammal air spaces are 
too low to be excited by most sounds produced by humans. Resonance of 
non-air containing tissues was not ruled out. While tissue trauma from 
resonance in air spaces seems highly unlikely, the group agreed that 
resonance in non-air containing tissues cannot be considered negated 
until certain experiments are performed. (PersComm with Dr. Roger L. 
Gentry, Workshop Organizer, NMFS Office of Protected Resources, 14 May 
2002)
    In summary, the best available scientific information shows that, 
while resonance can occur in marine animals, this resonance does not 
necessarily cause injury, and any such injury is not expected to occur 
below a sound pressure level of 180 dB. Because the Draft and Final 
OEIS/EISs used 180 dB as the criterion for the determination for the 
potential for injury to marine life and for the implementation of 
geographic and monitoring mitigation measures, any non-auditory 
physiological impacts associated with resonance were accounted for. The 
145-dB restriction for known recreational and commercial dive sites 
will provide an additional level of protection to marine animals in 
these areas. Based on this analysis, I have concluded that this claim 
does not constitute significant new information relevant to the 
employment of SURTASS LFA sonar that would require an SEIS.
    Additionally, it has been claimed that air space resonance impacts 
will cause damage to the lungs and large sinus cavities of cetaceans, 
that LFA sound could induce panic and subsequent problems with 
equalization, and that LFA sonar could cause bubble growth in blood 
vessels. With regard to the specific impacts to lungs and sinus 
cavities, there is abundant anatomical evidence that marine mammals 
have adapted to dramatic fluctuations in pressure. For example, marine 
mammal lungs are reinforced with more extensive connective tissues than 
their terrestrial relatives. These extensive connective tissues, 
combined with the probable collapse of the alveoli at the depths at 
which significant SURTASS LFA signals can be heard, make it very 
unlikely that significant lung resonance effects could be realized. 
Based on this analysis, I have concluded that this claim does not 
constitute significant new information relevant to the employment of 
SURTASS LFA sonar that would require an SEIS.
    Regarding the issue of equalization (or more correctly--
decompression), it is likely that marine mammals, which have evolved in 
an ambient hydrostatic pressure environment spanning several orders of 
magnitude [1:103], would be pre-disposed to have an innately 
rugged physiology for handling pressure changes and are unlikely to 
have problems with decompression. Therefore, it is unlikely that they 
would experience these problems. Based on this analysis, I have 
concluded that this claim does not constitute significant new 
information relevant to the employment of SURTASS LFA sonar that would 
require an SEIS.
    One of the letters (NRDC, 4 February 2002) cited a 2001 paper, 
which building on a theoretical model advanced in a paper published in 
1996, hypothesizes that intense, low-frequency sound could spur the 
growth of nitrogen bubbles in diving animals and result in embolism, 
hemorrhaging, and decompression sickness. According to the paper, 
marine mammals whose bodies are already saturated or supersaturated 
with nitrogen--a condition induced in at least some species by diving--
could be especially vulnerable to such injuries. The NRDC letter 
alleges that the potential for debilitating injury resulting from this 
process was not addressed by the Navy in its final EIS for the LFA 
system.
    The papers referred to above are ``Acoustically Enhanced Bubble 
Growth at Low Frequencies and Implication for Human Diver and Marine 
Mammal Safety'' by L.A. Crum and Y. Mao in the Journal of the 
Acoustical Society of America (1996), and ``Can Diving-induced Tissue 
Nitrogen Supersaturation Increase the Chance of Acoustically Driven 
Bubble Growth in Marine Mammals?'' by D. S. Houser, R. Howard, and S. 
Ridgway in the Journal of Theoretical Biology in 2001. The ``bubble 
growth'' issue as presented in Crum and Mao (1996) was discussed in the 
Final OEIS/EIS based on comments concerning possible effects on divers, 
even though that paper is also relevant to marine mammals. Both papers 
raised concerns regarding the potential for low frequency sound (note: 
in both papers, the authors considered ``low frequency'' to be below 
5,000 Hz; the SURTASS LFA Sonar Final OEIS/EIS, by contrast, defined 
``low frequency'' as below 1,000 Hz) to cause bubble growth from 
saturated and supersaturated gases in the blood (similar to the human 
diver condition known as the bends). Crum and Mao (1996), whose 
analysis was peer reviewed, concluded that sound pressure induced 
bubble growth would not be of concern until the sound pressure level 
exceeded 190 dB. Houser et al. (2001) hypothesized that due to their 
dive profiles, beaked and sperm whales could have high supersaturation 
of gases in their blood and tissues at or

[[Page 48152]]

near the end of their dive cycles (at or near the surface). At these 
high levels of supersaturation, the primary factor in producing bubble 
growth is static diffusion, which is not induced by sound pressure. 
Because the SURTASS LFA sonar monitoring mitigation measures will 
prevent marine mammals from being exposed to sound levels of 180 dB and 
above within the LFA mitigation zone, marine mammals will not be 
exposed to sound levels that could cause bubble growth due to 
supersaturation. Additionally, since high levels of supersaturation of 
gases in the tissue and blood are a normal part of marine mammal diving 
behavior, it must also be assumed that marine mammals have evolved 
mechanisms to deal with bubble growth by this method. Further, this 
evolutionary process has included marine mammal exposure to loud sound 
pressure levels from their own vocalizations and from others in the 
diving pod. Based on this analysis, I have concluded that this claim 
does not constitute significant new information relevant to the 
employment of SURTASS LFA sonar that would require an SEIS.
    Further, it is claimed there is a general correlation between naval 
maneuvers (which may include active sonar) and other mass strandings 
and multi-species strandings associated with beaked whales. The 
stranding information provided in the letters has been analyzed by both 
the Navy and NMFS. Based on this analysis, I have concluded that this 
claim does not constitute significant new information relevant to the 
employment of SURTASS LFA sonar that would require an SEIS.
    It has also been asserted that the interim report on the Bahamas 
stranding event (DoC and SECNAV, 2001) provides significant new 
information. For the following reasons, I have concluded that it does 
not.
    First, as the report notes, SURTASS LFA sonar was not involved in 
the Bahamas stranding, and it has been confirmed that SURTASS LFA sonar 
has never been associated with any strandings. Second, the LFS SRP made 
systematic evaluations of the animals most likely to be potentially 
affected by low frequency sound. While beaked whales, the primary 
species that stranded in the Bahamas, may be sensitive to frequencies 
above that employed by SURTASS LFA sonar, the available evidence does 
not show that they are more sensitive to low frequency sounds than the 
species selected as subjects for the LFS SRP (baleen whales).
    Finally, the interim report on the Bahamas stranding concluded that 
the cause of this stranding was the confluence of the Navy mid-range 
frequency sonar and contributory factors including the presence of a 
strong surface duct, unusual underwater bathymetry, constricted channel 
with limited egress, intensive active use of multiple sonar units over 
an extended period of time, and the presence of beaked whales that 
appear to be sensitive to the frequencies produced by these sonars.
    In addition to the geographic restrictions and monitoring 
mitigation protocols required for the proposed action (Alternative 1), 
the Navy will apply interim operational restrictions required by NMFS 
in the Final Rule that include a maximum frequency of 330 Hz and a 1-km 
buffer zone outside of the LFA mitigation zone. Taken as a whole, these 
protocols and SURTASS vessel maneuvering restrictions (due to the 
length of the acoustic arrays) will preclude employment in narrow 
channels surrounded by land such as those in the Bahamas.
    The letters have also asserted, in light of the interim Bahamas 
stranding report that resonance may have had an impact that caused the 
strandings, that the 180-dB threshold for injury is suspect for marine 
mammals, that baleen whales may also have stranded in the incident, and 
that the treatment of the incident in the Final EIS was dismissive.
    Possible impacts associated with resonance were discussed earlier. 
The Navy does not agree that the interim Bahamas stranding report 
raises doubts about using 180 dB as the basis for determining injury 
with respect to the SURTASS LFA Sonar Final OEIS/EIS. The Final OEIS/
EIS provides detailed discussions supporting the selection of 180 dB as 
the scientifically reasonable criterion for the potential onset of 
injury to marine mammals, and are not repeated here. In addition, 
research published after the Final OEIS/EIS was issued has strengthened 
this selection. Au and Andrews (2001) measured humpback whale calls off 
Hawaii at 189 dB; the average call source level for blue whales was 
calculated by McDonald et al. (2001) to be 186 dB; Charif et al. (2002) 
found source levels for fin whales up to 186 dB; and M[oslash]hl et al. 
(2000) recorded source levels for sperm whale clicks up to 223 dB. If 
marine mammals vocalize at these levels, it is reasonable to conclude 
that these species have also evolved mechanisms to protect themselves 
and conspecifics from high vocalization source levels.
    Two minke whales, which are baleen whales, stranded in the Bahamas, 
but in a different geographical area than the beaked whales. The minke 
whales returned to deep water and were not reported to re-strand, so no 
information about the cause or causes of their strandings is available.
    Based on the analysis discussed above, I have concluded that claims 
associated with the interim Bahamas stranding report do not constitute 
significant new information relevant to the employment of SURTASS LFA 
sonar that would require an SEIS.
    One of the letters claimed that the Final OEIS/EIS failed to 
discuss the cumulative or synergistic effects of operation of the 
SURTASS LFA sonar system in the same area with other low-frequency 
active sonar systems employed by other countries. All low frequency 
range active sonar systems used by other nations that the Navy is aware 
of are above 1 kHz, except for the SACLANTCEN (NATO) TVDS system. The 
NATO TVDS system has both mid- and low-frequency components with 
frequency ranges of 2.8 to 3.3 kHz and 450 to 700 Hz, respectively 
(SACLANTCEN, 1998). The U.S. Navy does not intend to operate SURTASS 
LFA sonar with this NATO system. I have concluded that the potential 
for SURTASS LFA sonar to operate with other low frequency systems is 
unlikely and, therefore, this claim does not constitute significant new 
information relevant to the employment of SURTASS LFA sonar that would 
require an SEIS.
    One letter also alleged that the Final OEIS/EIS failed to 
adequately discuss the use of new and advanced passive sonar 
technologies--such as Advanced Deployable Systems, towed arrays 
equipped with Acoustic Rapid Commercial-off-the-shelf Insertion (ARCI) 
processing, Robust Passive Sonar (RPS), and other systems--which have 
the potential to achieve the strategic goal of locating ``quiet'' 
submarines. As stated in the Final OEIS/EIS, LFA ``is an augmentation 
to the passive (SURTASS) detection system, and is planned for use when 
passive performance is inadequate.'' Under certain conditions, such as 
areas of high ambient (background) noise (e.g., high shipping density), 
passive sonar cannot detect quiet targets. Therefore, passive systems 
alone cannot meet the Navy's requirement to detect quiet, harder-to-
find submarines during all conditions, particularly at long ranges. 
Passive sonar technologies, such as the Advanced Deployable System 
(ADS), were discussed in the Final OEIS/EIS and also in the Final Rule. 
Additionally, SURTASS LFA sonar will have ARCI as its processor. 
Therefore, I have

[[Page 48153]]

concluded that this claim does not constitute significant new 
information relevant to the employment of SURTASS LFA sonar that would 
require an SEIS.
    Finally, one letter suggested that the Navy prepare an SEIS because 
the Final OEIS/EIS analysis relied heavily on behavioral audiograms 
obtained on bottlenose dolphins for its analysis of auditory impacts 
rather than the newly reported alternative, electro-physiological 
method (auditory brainstem response) for measuring hearing loss in 
marine mammals. The letter stated that results indicate that hearing 
loss in bottlenose dolphins may occur to a greater degree and possibly 
at lower levels of exposure than had been presumed using behavioral 
techniques.
    The auditory brainstem response (ABR) method referenced in the 
letter was used to measure temporary threshold shift (TTS), not to 
measure hearing loss. Additionally, an abstract received from the 
principal investigator on the referenced research states, ``Following 
the collection of the evoked auditory potential thresholds, the 
dolphin's thresholds were also reexamined using a conventional standard 
behavioral psychophysical procedure. The data show very similar 
thresholds using the two different procedures'' (PersComm with Dr. P.E. 
Nachtigall, 11 February 2002). Thus, the Navy's analysis in the Final 
OEIS/EIS remains valid. Furthermore, the Navy did not rely primarily on 
behavioral audiograms obtained on bottlenose dolphins in the Final 
OEIS/EIS for the analysis of auditory impacts. The subject study by 
Schlundt et al., (2000) was only one set of data used to estimate the 
potential effects on marine mammal hearing, which included marine 
mammal hearing thresholds, extrapolation from human hearing loss 
studies, temporary threshold shift studies, and comparison to fish 
hearing studies. Therefore, I have concluded that this claim does not 
constitute significant new information relevant to the employment of 
SURTASS LFA sonar that would require an SEIS.
    NMFS received several comments under their Proposed Rulemaking 
regarding the Navy's Final OEIS/EIS. The Navy has worked closely with 
NMFS in responding to these comments, which have been incorporated into 
NMFS Final Rule for the Taking of Marine Mammals Incidental to Navy 
Operations of SURTASS LFA Sonar (Federal Register July 16, 2002). In 
making the decision regarding employment of the SURTASS LFA sonar 
system, the Navy has fully considered the responses to comments within 
the NMFS Final Rule for the Taking of Marine Mammals Incidental to Navy 
Operations of SURTASS LFA Sonar.

Other Considerations

    On June 10, 2002, the General Accounting Office (GAO) completed an 
investigation into the Defense Acquisition of the SURTASS LFA Sonar and 
issued a report (GAO-02-692) entitled, ``Testing Needed to Prove 
SURTASS/LFA Effectiveness in Littoral Waters.'' This exhaustive 
examination concluded that the primary benefit of SURTASS LFA sonar is 
that it will provide a significant increase in long-range undersea 
detection capabilities in the open ocean, with fewer assets and 
operators than other technologies, thus, validating the purpose as 
defined in the SURTASS LFA Sonar Final EIS. In its singular 
recommendation, GAO stated that the Navy should establish a test plan 
and conduct testing of the system to demonstrate its capabilities in 
littoral areas, which they defined as coastal, near-shore regions. 
Future testing pursuant to this decision will include testing in the 
littorals. Therefore, I have concluded that this report does not 
provide any significant new information relevant to the employment of 
SURTASS LFA sonar that would require an SEIS.
    In a recent article (Croll, D.A, C.W. Clark, A. Acevedo, B. Tershy, 
S. Flores, J. Gedamke, and J. Urban. 2002. ``Bioacoustics: Only male 
fin whales sing loud songs.'' Brief Communications, Nature 417: 809), 
the authors concluded, ``. . . .the recovery of fin- and blue-whale 
populations from past exploitation could be impeded by low-frequency 
sounds generated by human activity.'' These low-frequency vocalizations 
are considered to be breeding displays by males. They also stated, ``An 
increase in ambient noise could thus reduce the distance over which 
receptive females might hear the vocalizations of males.'' One of the 
coauthors, Dr. Chris Clark of Cornell University, was a principal 
investigator on the LFS SRP and a preparer/reviewer of the Final OEIS/
EIS. He has stated that the low frequency contribution to ambient noise 
of greatest concern is from commercial shipping. He also stated that 
SURTASS LFA sonar does not contribute to ambient noise in the frequency 
band of fin whale and blue whale songs (below 100 Hz). Further, the 
information presented in Croll et al. (2002) was known during the 
preparation of and is consistent with the conclusions of the SURTASS 
LFA Final OEIS/EIS. Therefore, I have concluded that this article does 
not provide any significant new information relevant to the employment 
of SURTASS LFA sonar that would require an SEIS.

Conclusions

    I have considered the following issues relative to the potential 
environmental impacts from the employment of the SURTASS LFA sonar 
system including, but not limited to, adequacy of scientific 
information on human divers and the Navy sponsored research to study 
the potential effects of low frequency sound on divers to fill these 
gaps; adequacy of scientific information on marine animals and the Low 
Frequency Sound Scientific Research Program conducted by independent 
bioacousticians and marine biologists; development of impact criteria 
including risk continuum and thresholds; analytical methodology, 
analyses, and results of the determination of potential impacts; the 
NOAA/Navy Joint Interim Report Bahamas Marine Mammal Stranding Event of 
15-16 March 2000 as it relates to the potential for SURTASS LFA sonar 
to cause tissue damage/injury to marine mammals; resonance and bubble 
growth issues as they relate to the potential for SURTASS LFA sonar to 
cause tissue damage/injury to marine animals; NMFS Final Rule for the 
Taking of Marine Mammals Incidental to Navy Operations of Surveillance 
Towed Array Sensor System Low Frequency Active Sonar and their response 
to comments received on the Proposed Rule; NMFS Biological Opinion on 
the Navy's Proposed Employment of Surveillance Towed Array Sensor 
System Low Frequency Active Sonar; comments received on the SURTASS LFA 
Sonar Final OEIS/EIS; and requests from environmental groups for the 
Navy to prepare a supplemental EIS based on significant new 
information.
    Based upon my review of the comparative analysis of the potential 
for environmental and socioeconomic effects from the three alternatives 
presented in the Final OEIS/EIS and public comments received during the 
NEPA process, I have decided to implement Alternative 1 of the Final 
OEIS/EIS, which was identified as the Navy's preferred alternative, 
with certain geographical restrictions and monitoring mitigation 
designed to reduce potential adverse effects on the marine environment, 
but only to employ two SURTASS LFA sonar systems rather than the four 
systems analyzed under Alternative 1. Only two SURTASS LFA sonar 
systems will be available during the next five years. There is no 
budget identified for any further SURTASS LFA sonar systems through 
fiscal year 2007. This decision permits the Navy to

[[Page 48154]]

reasonably fulfill its purpose of providing U.S. forces with reliable, 
effective, and efficient long-range detection of new-generation, quiet 
submarines, while the geographic restrictions and monitoring mitigation 
requirements constitute all practical means to avoid or minimize 
environmental harm from the alternative selected. In addition, this 
decision and implementation of this alternative provide for continued 
long-term monitoring and research, which will further enhance the 
understanding of the potential effects of anthropogenic sounds on the 
marine environment.
    Actions requiring issuance of NMFS Letter(s) of Authorization 
(LOA[s]) are being addressed through NMFS rulemaking under 50 CFR part 
216 and the Final Rule (Federal Register, 16 July 2002). Actions 
requiring issuance of incidental take statements (ITS[s]) are being 
addressed as part of the NMFS Biological Opinion on the U.S. Navy's 
proposed use of SURTASS LFA Sonar that has been prepared by NMFS in 
accordance with section 7 of the Endangered Species Act (ESA) of 1973, 
as amended (16 U.S.C. 1531 et seq.) (Consultation No. F/FPR/2000/00483, 
dated 30 May 2002).
    Operational employment of the SURTASS LFA sonar system onboard the 
R/V Cory Chouest is contingent upon issuance of a LOA for that system, 
which the Navy anticipates being issued with an effective date of 15 
August 2002 (30 days after the Final Rule is published in the Federal 
Register), in specific bio-geographic provinces approved for 
operations. Operational employment is also contingent upon issuance of 
an ITS concurrent with the above LOA and for the same specified bio-
geographic provinces.
    Operational employment of the second SURTASS LFA sonar system is 
contingent upon issuance of a LOA and ITS for that system, in specified 
bio-geographic provinces approved for operation. The LOA and ITS for 
this system will be requested by the Navy in accordance with the above 
regulations when appropriate.

    Dated: July 16, 2002.
Donald R. Schregardus,
Deputy Assistant Secretary of the Navy, (Environment).
[FR Doc. 02-18592 Filed 7-22-02; 8:45 am]
BILLING CODE 3810-FF-P