Takes of Marine Mammals Incidental to Specified Activities; Pile Placement for ORPC Maine's Cobscook Bay Tidal Energy Pilot Project, 15045-15052 [2012-6196]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 77, Number 50 (Wednesday, March 14, 2012)]
[Notices]
[Pages 15045-15052]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-6196]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XA916


Takes of Marine Mammals Incidental to Specified Activities; Pile 
Placement for ORPC Maine's Cobscook Bay Tidal Energy Pilot Project

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Commerce.

ACTION: Notice; issuance of an incidental harassment authorization.

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SUMMARY: In accordance with the Marine Mammal Protection Act (MMPA) 
implementing regulations, notification is hereby given that NMFS has 
issued an Incidental Harassment Authorization (IHA) to Ocean Renewable 
Power Company Maine, LLC (ORPC), allowing the take of small numbers of 
marine mammals, by Level B harassment only, incidental to pile driving 
in Cobscook Bay, Maine.

DATES: Effective March 12, 2012, through March 11, 2013.

ADDRESSES: A copy of the IHA, the application, and the Environmental 
Assessment may be obtained by writing to Tammy Adams, Acting Chief, 
Permits and Conservation Division, Office of Protected Resources, 
National Marine Fisheries Service, 1315 East-West Highway, Silver 
Spring, MD 20910 or by telephoning the contact listed here (see FOR 
FURTHER INFORMATION CONTACT), or visiting the Internet at: https://www.nmfs.noaa.gov/pr/permits/incidental.htm#applications. Documents 
cited in this notice may be viewed, by appointment, during regular 
business hours, at the aforementioned address.

FOR FURTHER INFORMATION CONTACT: Michelle Magliocca, Office of 
Protected Resources, NMFS, (301) 427-8401.

SUPPLEMENTARY INFORMATION:

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct the Secretary of Commerce to allow, upon request, the 
incidental, but not intentional, taking of small numbers of marine 
mammals by U.S. citizens who

[[Page 15046]]

engage in a specified activity (other than commercial fishing) within a 
specific geographical region if certain findings are made and either 
regulations are issued or, if the taking is limited to harassment, a 
notice of a proposed authorization is provided to the public for 
review.
    Authorization for incidental takings shall 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 (where 
relevant), and if the permissible methods of taking and requirements 
pertaining to the mitigation, 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.''
    Section 101(a)(5)(D) of the MMPA established an expedited process 
by which U.S. citizens can apply for an authorization to incidentally 
take small numbers of marine mammals by harassment. Section 
101(a)(5)(D) further established a 45-day time limit for NMFS' review 
of an application, followed by a 30-day public notice and comment 
period on any proposed authorizations for the incidental harassment of 
marine mammals. Within 45 days of the close of the comment period, NMFS 
must either issue or deny the authorization.
    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as: any act of pursuit, torment, or 
annoyance which (i) has the potential to injure a marine mammal or 
marine mammal stock in the wild [Level A harassment]; or (ii) has the 
potential to disturb a marine mammal or marine mammal stock in the wild 
by causing disruption of behavioral patterns, including, but not 
limited to, migration, breathing, nursing, breeding, feeding, or 
sheltering [Level B harassment].

Summary of Request

    On November 2, 2011, NMFS received an application from ORPC 
requesting an IHA for the take, by Level B harassment, of small numbers 
of harbor seal (Phoca vitulina), gray seal (Halichoerus grypus), harbor 
porpoise (Phocoena phocoena), and Atlantic white-sided dolphin 
(Lagenorhynchus acutus) incidental to pile driving activities in 
Cobscook Bay, Maine. In accordance with the MMPA and implementing 
regulations, NMFS issued a notice in the Federal Register on January 
19, 2012 (77 FR 2701), requesting comments from the public on the 
proposed IHA.

Description of the Specified Activity

    A complete description of the specified activity may be found in 
NMFS' proposed IHA notice (77 FR 2701, January 19, 2012) and a summary 
is provided here. ORPC plans to install foundational piles to support 
an underwater tidal turbine unit as part of the first phase of a long-
term project. The turbine unit is approximately 30 meters (m) (98 feet 
(ft)) long, 5 m (17 ft) high, and 5 m (17 ft) wide and is attached to a 
bottom support frame, which holds the unit in place about 4.5 m (15 ft) 
above the sea floor. The turbine unit weighs about 69,000 pounds (lbs) 
and is coupled with the bottom support frame to comprise what is called 
a single-device TidGen\TM\ Power System. At the interface with the 
seabed, the bottom support frame requires a site-specific design based 
on the environmental conditions at the deployment area. The foundation 
design for the single-device TidGen\TM\ Power System is a pile bent 
arrangement consisting of 10 steel pipe piles. Each foundation pile 
will have a 76-centimeter (cm) (30 inch (in)) diameter and a 1-cm 
(half-inch) wall thickness and will rest on bedrock. Piles will vary in 
length from 15-18 m (50-60 ft) due to bottom sediment depth, but each 
pile will be driven to the top of bedrock and will protrude 3-5 m (10-
15 ft) above the seafloor.
    A total of 11 piles (10 for the foundation and one for mounting 
environmental monitoring equipment) will be driven from a moored barge 
for the first phase. Piles will be placed about six m (20 ft) apart in 
two rows of five and the rows will be separated by about 15 m (50 ft). 
Geotechnical data shows that the TidGen\TM\ device will be located in 
an area with up to 12 m (40 ft) of marine clay and some thin layers of 
glacial till overlaying bedrock. Based on this data and extensive soil 
studies in the area, piles are expected to sink fairly deep into the 
mud line under their own weight. Piles will be driven the remaining 
depth using vibratory and impact pile driving procedures from barge-
based pile driving equipment. A pile for mounting environmental 
monitoring equipment will also be installed with the same pile driving 
equipment. The monitoring pile will be two m (six ft) in diameter, or 
consist of an array of three piles not greater than 76 cm (30 in) in 
diameter. The monitoring pile will protrude about six m (20 ft) above 
the seafloor.
    ORPC plans to use an H&M model H-1700 vibratory hammer to drive 
piles to the extent possible. If additional energy is required to reach 
bedrock, a Berminghammer model B-3505 diesel impact hammer may be used, 
with maximum rated impact energy of 21,533 ft-lb. ORPC expects that the 
need for an impact hammer will be minimal and for very short durations. 
To lessen the amount and intensity of sound propagation, ORPC is 
evaluating the use of wooden sound absorption cushions and/or bubble 
curtains.

Date and Duration of Proposed Activity

    ORPC plans to begin pile driving in mid-March, 2012. Pile driving 
with a vibratory hammer may take up to three minutes per pile and pile 
driving with an impact hammer may take up to five minutes per pile. Due 
to strong currents during ebb and flood tides, pile driving will only 
occur during slack tides. ORPC expects that only one pile will be 
driven per tide cycle for a total of 7-12 days of pile driving during 
daylight hours only. NMFS Northeast Region recommends that in-water 
construction involving pile driving be conducted between November 8 and 
April 9 to avoid impacts to fisheries resources. However, ORPC may be 
able to conduct pile driving activities after April 9 if they can 
demonstrate that noise levels caused by the impact hammer are below 
NMFS guidelines. Although pile driving is only expected to last 7-12 
days, NMFS issued the IHA for a 1-year period to allow for permitting 
and weather delays. Pile driving will only occur in weather that 
provides adequate visibility for marine mammal monitoring activities.

Region of Proposed Activity

    The activity will occur in Cobscook Bay, in between Lubec and 
Eastport, Maine. Piles and other deployment materials will be 
transported by barge from a staging area at the Eastport Boat School or 
other local access point. Cobscook Bay has extremely strong tidal 
currents and notably high tides, creating an extensive intertidal 
habitat for marine and coastal species. Water depth at the proposed 
project location is 26 m (85 ft) at mean lower low water. The Bay is 
considered a relatively intact marine system, as the area has not 
experienced much industrialization.

Sound Propagation

    For background, sound is a mechanical disturbance consisting of 
minute vibrations that travel through a medium, such as air or water, 
and is generally characterized by several variables. Frequency 
describes the

[[Page 15047]]

sound's pitch and is measured in hertz (Hz) or kilohertz (kHz), while 
sound level describes the sound's loudness and is measured in decibels 
(dB). Sound level increases or decreases exponentially with each dB of 
change. For example, 10 dB yields a sound level 10 times more intense 
than 1 dB, while a 20 dB level equates to 100 times more intense, and a 
30 dB level is 1,000 times more intense. Sound levels are compared to a 
reference sound pressure (micro-Pascal) to identify the medium. For air 
and water, these reference pressures are ``re: 20 [mu]Pa'' and ``re: 1 
[mu]Pa,'' respectively. Root mean square (RMS) is the quadratic mean 
sound pressure over the duration of an impulse. RMS is calculated by 
squaring all of the sound amplitudes, averaging the squares, and then 
taking the square root of the average (Urick, 1975). RMS accounts for 
both positive and negative values; squaring the pressures makes all 
values positive so that they may be accounted for in the summation of 
pressure levels (Hastings and Popper, 2005). This measurement is often 
used in the context of discussing behavioral effects, in part because 
behavioral effects, which often result from auditory cues, may be 
better expressed through averaged units rather than by peak pressures.
    Source levels for the vibratory and impact hammer are expected to 
be 175 dB and 190 dB, respectively. Assuming a practical spreading loss 
of 15 log R, OPRC estimates that the 180-dB (Level A harassment) 
isopleth for the impact hammer could be as far as 100 m (328 ft). The 
120-dB (Level B harassment for continuous sound sources) isopleth for 
the vibratory hammer could be as far as 4,600 m (2.5 mi).

Comments and Responses

    A notice of receipt and request for public comment on the 
application and proposed authorization was published on January 19, 
2012 (77 FR 2701). During the 30-day public comment period, NMFS only 
received comments from the Marine Mammal Commission (Commission).
    Comment 1: The Commission recommends that NMFS defer issuance of 
the IHA until NMFS evaluates the potential effects of construction, 
installation, and subsequent operation of the tidal turbine. 
Furthermore, the Commission recommends that NMFS then use that 
information as a basis for (1) determining the potential for marine 
mammal injury or mortality, (2) designing mitigation and monitoring 
measures to minimize injury and mortality caused by direct 
interactions, and (3) determining whether the anticipated takes are 
expected to have negligible impacts on marine mammal species and 
stocks.
    Response: NMFS disagrees that issuance of the IHA should be 
deferred. ORPC requested authorization for incidental takings subject 
to a specified activity (i.e., pile driving). NMFS has not received an 
IHA request for incidental takings subject to further construction, 
installation, or subsequent operation of the tidal turbine. However, 
NMFS did analyze the cumulative effects of ongoing and future Cobscook 
Bay activities in an Environmental Assessment (EA), which included the 
eventual operation of ORPC's tidal turbine. The environmental effects 
of ORPC's long-term project were also analyzed in an EA prepared by the 
Federal Energy Regulatory Commission and the Department of Energy (FERC 
and DOE, 2012). In summary, an assortment of mitigation and monitoring 
measures are expected to minimize impacts to marine species and the 
surrounding environment. To date, information on currently operating 
tidal turbines does not suggest the need for an incidental take 
authorization. However, if ORPC determines that there is a potential 
for further marine mammal harassment, they may choose to apply for 
another authorization.
    Comment 2: If an IHA is issued, the Commission recommends that NMFS 
authorize the taking of harbor seals and gray seals by both in-water 
and in-air harassment. If authorization does not include both in-water 
and in-air harassment, the Commission recommends that NMFS require ORPC 
to shutdown pile driving activities whenever a seal is observed within 
the in-air Level B harassment zone.
    Response: As explained in the notice of proposed IHA (77 FR 2701, 
January 19, 2012), elevated in-air sound levels are not a concern 
because the nearest significant haul-out is more than six nautical 
miles (nmi) away. ORPC has not observed any pinnipeds hauled out within 
the proposed project area during their 3 years of conducting visual 
observations in Cobscook Bay. Any pinniped observed swimming or diving 
within 152 m (500 ft) of the pile driving location would be considered 
to be taken by elevated underwater sounds from pile driving; therefore, 
there is no additional need to shutdown any time a pinniped is within 
the in-air Level B harassment zone.
    Comment 3: The Commission recommends that NMFS require ORPC to 
monitor the presence and behavior of marine mammals for 30 minutes 
before, during, and 30 minutes after all impact and vibratory pile 
driving activities.
    Response: As detailed in the notice of proposed IHA (77 FR 2701, 
January 19, 2012) and the mitigation and monitoring sections of this 
notice, ORPC is required to monitor the exclusion zone for 30 minutes 
before, during, and 30 minutes after all impact pile driving. ORPC is 
also required to monitor the larger Level B harassment zone on at least 
three days of vibratory pile driving. NMFS believes that this amount of 
monitoring is sufficient to prevent the injury or mortality of marine 
mammals and to document behavioral responses of marine mammals to pile 
driving.
    Comment 4: The Commission recommends that NMFS require ORPC to 
record distances to observed marine mammals and document their behavior 
within the entirety of the Level B harassment zone for vibratory pile 
driving.
    Response: As detailed in the notice of proposed IHA (77 FR 2701, 
January 19, 2012) and the mitigation and monitoring sections of this 
notice, ORPC is required to monitor the Level B harassment zone on at 
least three days of vibratory pile driving to validate take estimates 
and evaluate the behavioral impacts pile driving has on marine mammals 
out to the Level B harassment isopleth. Protected species observers 
will record species, behaviors, and responses to pile driving within 
this area.
    Comment 5: The Commission recommends that NMFS require ORPC to 
monitor before, during, and after all soft-starts of vibratory and 
impact pile driving activities to gather the data needed to determine 
the effectiveness of this technique as a mitigation measure.
    Response: NMFS disagrees that ORPC needs to monitor for marine 
mammals before, during, and after all soft-starts. Protected species 
observers will be on-site and monitoring for marine mammals at least 30 
minutes before, during, and 30 minutes after all impact driving 
(including during soft-starts) and on at least three days of vibratory 
pile driving. NMFS believes that monitoring for all impact driving and 
on at least three days of vibratory pile driving will allow for 
adequate interpretation of how marine mammals are behaving in response 
to pile driving, including during soft-starts.

Description of Marine Mammals in the Area of the Specified Activity

    Marine mammals with known presence in this region of Cobscook Bay 
are the harbor seal, grey seal, harbor porpoise, and Atlantic white-
sided dolphin. ORPC has been conducting incidental visual observations 
of marine mammals in Cobscook Bay since 2007, for a total effort of 252 
4-hr

[[Page 15048]]

observational periods over 222 days. During this time, marine mammal 
observers have recorded 57 seals, 47 harbor porpoises, and two Atlantic 
white-sided dolphins (Table 1). No observations of any whale species 
have been made in Cobscook Bay by ORPC since monitoring began in 2007. 
In addition, a review of available databases does not indicate any 
recorded whale sightings in Cobscook Bay. Other species that may 
possibly occur in the vicinity of the proposed activity include North 
Atlantic right whale (Eubalaena glacialis), humpback whale (Megaptera 
novaengliae), fin whale (Balaenoptera borealis), minke whale 
(Balaenoptera acutorostrata), and sei whale (Balaenoptera borealis). 
However, these five species are generally associated with open ocean 
habitats and occur in more offshore locations. NMFS has concluded that 
the specified activity will not impact these five species and they are 
not discussed further. Information on the harbor seal, grey seal, 
harbor porpoise, and Atlantic white-sided dolphin was provided in the 
January 19, 2012 Federal Register notice (77 FR 2701).

  Table 1--Marine Mammal Observations in the Proposed Project Vicinity Between December 2007, and December 2010
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                                                     Hours of       Harbor and        Harbor      Atlantic white-
                      Month                           effort         grey seal       porpoise      sided dolphin
----------------------------------------------------------------------------------------------------------------
January.........................................              16               0               0               0
February........................................              36               0               1               0
March...........................................              56               1               0               0
April...........................................             160               4               3               0
May.............................................              56               1               3               0
June............................................              84               8               1               0
July............................................              84               4              10               0
August..........................................             120              16              24               2
September.......................................             100               9               5               0
October.........................................              96               8               0               0
November........................................              72               4               0               0
December........................................             104               2               0               0
                                                 ---------------------------------------------------------------
    Total.......................................           1,008              57              47               2
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Potential Effects on Marine Mammals

    Elevated in-water sound levels from pile driving in the project 
area may temporarily impact marine mammal behavior. A detailed 
description of potential impacts to marine mammals can be found in 
NMFS' January 19, 2012 Federal Register notice (77 FR 2701) and is 
summarized here.
    Marine mammals are continually exposed to many sources of sound. 
For example, lightning, rain, sub-sea earthquakes, and animals are 
natural sound sources throughout the marine environment. Marine mammals 
produce sounds in various contexts and use sound for various biological 
functions including, but not limited to, (1) social interactions; (2) 
foraging; (3) orientation; and (4) predator detection. Interference 
with producing or receiving these sounds may result in adverse impacts. 
Audible distance or received levels will depend on the sound source, 
ambient noise, and the sensitivity of the receptor (Richardson et al., 
1995). Marine mammal reactions to sound may depend on sound frequency, 
ambient sound, what the animal is doing, and the animal's distance from 
the sound source (Southall et al., 2007).

Hearing Impairment

    Marine mammals may experience temporary or permanent hearing 
impairment when exposed to loud sounds. Hearing impairment is 
classified by temporary threshold shift (TTS) and permanent threshold 
shift (PTS). There are no empirical data for when PTS first occurs in 
marine mammals; therefore, it must be estimated from when TTS first 
occurs and from the rate of TTS growth with increasing exposure levels. 
PTS is likely if the animal's hearing threshold is reduced by >= 40 dB 
of TTS. PTS is considered auditory injury (Southall et al., 2007) and 
occurs in a specific frequency range and amount. Irreparable damage to 
the inner or outer cochlear hair cells may cause PTS; however, other 
mechanisms are also involved, such as exceeding the elastic limits of 
certain tissues and membranes in the middle and inner ears and 
resultant changes in the chemical composition of the inner ear fluids 
(Southall et al., 2007). Due to proposed mitigation measures and source 
levels in the proposed project area, NMFS does not expect marine 
mammals to be exposed to PTS levels.

Temporary Threshold Shift (TTS)

    TTS is the mildest form of hearing impairment that can occur during 
exposure to a loud sound (Kryter, 1985). While experiencing TTS, the 
hearing threshold rises and a sound must be louder in order to be 
heard. TTS can last from minutes or hours to days, but is recoverable. 
TTS also occurs in specific frequency ranges; therefore, an animal 
might experience a temporary loss of hearing sensitivity only between 
the frequencies of 1 and 10 kHz, for example. The amount of change in 
hearing sensitivity is also variable and could be reduced by 6 dB or 30 
dB, for example. Recent literature highlights the inherent complexity 
of predicting TTS onset in marine mammals, as well as the importance of 
considering exposure duration when assessing potential impacts (Mooney 
et al., 2009a, 2009b; Kastak et al., 2007). Generally, with sound 
exposures of equal energy, quieter sounds (lower SPL) of longer 
duration were found to induce TTS onset more than louder sounds (higher 
SPL) of shorter duration (more similar to subbotom profilers). For 
sound exposures at or somewhat above the TTS-onset threshold, hearing 
sensitivity recovers rapidly after exposure to the sound ends. Southall 
et al. (2007) considers a 6 dB TTS (i.e., baseline thresholds are 
elevated by 6 dB) to be a sufficient definition of TTS-onset. NMFS 
considers TTS as Level B harassment that is mediated by physiological 
effects on the auditory system; however, NMFS does not consider onset 
TTS to be the lowest level at which Level B harassment may occur.

Behavioral Effects

    Behavioral responses to sound are highly variable and context-
specific. An

[[Page 15049]]

animal's perception of and response to (in both nature and magnitude) 
an acoustic event can be influenced by prior experience, perceived 
proximity, bearing of the sound, familiarity of the sound, etc. 
(Southall et al., 2007). If a marine mammal does react briefly to an 
underwater sound by changing its behavior or moving a small distance, 
the impacts of the change are unlikely to be significant to the 
individual, let alone the stock or populations. However, if a sound 
source displaces marine mammals from an important feeding or breeding 
area for a prolonged period, impacts on individuals and populations 
could be significant (e.g., Lusseau and Bejder, 2007; Weilgart, 2007). 
Based on the limited amount of pile driving and use of vibratory pile 
driving, any impacts to marine mammal behavior from ORPC's pile driving 
operations are expected to be temporary. Any disturbance to marine 
mammals is likely to be in the form of temporary avoidance or 
alteration of opportunistic foraging behavior near the pile driving 
location.

Non-pulse Sounds

    The studies that address responses of mid-frequency cetaceans (such 
as Atlantic white-sided dolphins) to non-pulse sounds (like vibratory 
pile driving) include data gathered both in the field and the 
laboratory and related to several different sound sources (of varying 
similarity to chirps) including: pingers, drilling playbacks, ship and 
ice-breaking noise, vessel noise, acoustic harassment devices (AHDs), 
acoustic deterrent devices (ADDs), mid-frequency active sonar, and non-
pulse bands and tones. While none of these studies are specific to 
Atlantic white-sided dolphins, they include species with similar 
auditory bandwidths. Southall et al. (2007) were unable to come to a 
clear conclusion regarding the results of these studies. In some cases 
animals in the field showed significant responses to received levels 
between 90 and 120 dB, while in other cases these responses were not 
seen in the 120 to 150 dB range. This disparity is likely due to 
contextual variables beyond received level and species differences.
    The studies that address responses of high-frequency cetaceans 
(such as the harbor porpoise) to non-pulse sounds include data gathered 
both in the field and the laboratory and related to several different 
sound sources (of varying similarity to chirps), including: pingers, 
AHDs, and various laboratory non-pulse sounds. All of these data were 
collected from harbor porpoises. Southall et al. (2007) concluded that 
the existing data indicate that harbor porpoises are likely sensitive 
to a wide range of anthropogenic sounds at low received levels (around 
90 to 120 dB), at least for initial exposures. All recorded exposures 
above 140 dB induced profound and sustained avoidance behavior in wild 
harbor porpoises (Southall et al., 2007). Rapid habituation was noted 
in some but not all studies.
    There are limited data available on the behavioral effects of non-
pulse noise on pinnipeds while underwater; however, field and captive 
studies to date collectively suggest that pinnipeds do not react 
strongly to exposures between 90 and 140 dB re: 1 [mu]Pa; no data exist 
from exposures at higher levels.

Impulse Sounds

    Southall et al. (2007) also addressed behavioral responses of 
marine mammals to impulse sounds (like impact pile driving). The 
studies that address the responses of mid-frequency cetaceans to 
impulse sounds include data gathered both in the field and the 
laboratory and related to several different sound sources (of varying 
similarity to boomers), including: small explosives, airgun arrays, 
pulse sequences, and natural and artificial pulses. The data show no 
clear indication of increasing probability and severity of response 
with increasing received level. Behavioral responses seem to vary 
depending on species and stimuli. Data on behavioral responses of high-
frequency cetaceans to multiple pulses is not available. Although 
individual elements of some non-pulse sources (such as pingers) could 
be considered pulses, it is believed that some mammalian auditory 
systems perceive them as non-pulse sounds (Southall et al., 2007).
    The studies that address the responses of pinnipeds in water to 
impulse sounds include data gathered in the field and related to 
several different sources, including: small explosives, impact pile 
driving, and airgun arrays. Quantitative data on reactions of pinnipeds 
to impulse sounds is limited, but a general finding is that exposures 
in the 150 to 180 dB range generally have limited potential to induce 
avoidance behavior (Southall et al., 2007).
    As discussed below, impacts to marine mammal reproduction are not 
anticipated because there are no known pinniped rookeries within the 
proposed project area and Cobscook Bay is not a known breeding ground 
for cetaceans. Marine mammals may avoid the area around the hammer, 
thereby reducing their exposure to elevated sound levels. NMFS expects 
any impacts to marine mammal behavior to be temporary, Level B 
harassment (for example, avoidance or alteration of behavior). ORPC 
conservatively assumes 12 pile driving days may occur over the validity 
of the IHA. Marine mammal injury or mortality is not likely, as the 180 
dB isopleth (NMFS' Level A harassment threshold for cetaceans) for the 
impact hammer is expected to be no more than a 100-m (328 ft) radius. 
ORPC proposes to continuously monitor a 152-m (500-ft) area around the 
sound source and cease all pile driving if a marine mammal is observed 
nearing or within this 152-m (500-ft) isopleth.

Anticipated Effects on Habitat

    No permanent detrimental impacts to marine mammal habitat are 
expected to result from pile driving. Pile driving (resulting in 
temporary ensonification) may impact prey species and marine mammals by 
causing avoidance or abandonment of the area; however these impacts are 
expected to be local and temporary. The benthic impact of the 
foundation for this phase of the proposed project will be about 10 m\2\ 
(113 ft\2\) during pile placement. While the foundation frame will take 
up a limited amount of space on the seafloor, there are no expected 
adverse impacts to marine mammal habitat.

Mitigation Measures

    In order to issue an IHA under section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to such 
activity, and other means of effecting the least practicable adverse 
impact on such species or stock and its habitat, paying particular 
attention to rookeries, mating grounds, and areas of similar 
significance, and on the availability of such species or stock for 
taking for certain subsistence uses. There are no subsistence hunting 
grounds within the action area and since the activity will not result 
in marine mammal mortality, the availability of marine mammals for 
subsistence uses will not be impacted. ORPC will implement the 
following mitigation measures to minimize adverse impacts to marine 
mammals:

Sound Attenuation Device

    When using a diesel impact hammer to ``proof'' piles, ORPC will use 
wooden sound absorption cushions and/or a bubble curtain to reduce 
hydroacoustic sound levels and avoid the potential for marine mammal 
injury. Based on previous studies, sound attenuation devices are 
expected to reduce sound levels by at least 5 dB.

[[Page 15050]]

Exclusion Zone

    The purpose of the proposed exclusion zone is to prevent Level A 
harassment (injury) of any marine mammal species. Current NMFS practice 
regarding exposure of marine mammals to anthropogenic sound is that in 
order to avoid the potential for injury (PTS), cetaceans and pinnipeds 
should not be exposed to impulsive sounds of 180 and 190 dB or above, 
respectively. These levels are considered precautionary as it is likely 
that more intense sounds would be required before injury would actually 
occur (Southall et al., 2007). During all in-water impact pile driving, 
ORPC will establish a preliminary marine mammal exclusion zone around 
each pile to avoid exposure to sounds at or above 180 dB. The 
preliminary exclusion zone will have a radius of 152 m (500 ft). This 
encompasses the initial estimate of the 180 dB isopleth, where injury 
could occur, plus a 52-m (171-ft) buffer zone. Once hydroacoustic 
monitoring is conducted, the exclusion and buffer zone may be adjusted 
accordingly so that marine mammals are not exposed to Level A 
harassment sound pressure levels. The exclusion zone will be monitored 
continuously during impact pile driving to ensure that no marine 
mammals enter the area. Protected species observers (PSOs) will be 
stationed on two observer boats, one 152 m (500 ft) upstream and one 
152 m (500 ft) downstream of the installation site. One observer on 
each vessel will survey the exclusion zone, while the second observer 
will conduct behavioral monitoring outwards to a distance of 1 nmi. 
Several floats anchored at 152 m (500 ft) and 305 m (1,000 ft) will be 
located around the installation site to help identify when marine 
mammals are entering or within the exclusion zone. An exclusion zone 
for vibratory pile driving or installation of concrete piles is 
unnecessary as source levels will not exceed the Level A harassment 
threshold.

Pile Driving Shut Down and Delay Procedures

    If a PSO sees a marine mammal within or approaching the exclusion 
zone prior to start of impact pile driving, the observer will notify 
the on-site project lead (or other authorized individual) who will then 
be required to delay pile driving until the marine mammal has moved 305 
m (1,000 ft) from the sound source or if the animal has not been 
resighted within 30 minutes. If a marine mammal is sighted within or on 
a path toward the 152-m (500-ft) exclusion zone during pile driving, 
pile driving will cease until that animal has moved 305 m (1,000 ft) 
and is on a path away from the exclusion zone or 30 minutes has lapsed 
since the last sighting.

Soft-start Procedures

    A ``soft-start'' technique will be used at the beginning of each 
pile installation to allow any marine mammal that may be in the 
immediate area to leave before the pile hammer reaches full energy. For 
vibratory pile driving, the soft-start procedure requires contractors 
to initiate noise from the vibratory hammer for 15 seconds at 40-60 
percent reduced energy followed by a 1-minute waiting period. The 
procedure will be repeated two additional times before full energy may 
be achieved. For impact hammering, contractors will be required to 
provide an initial set of three strikes from the impact hammer at 40 
percent energy, followed by a 1-minute waiting period, then two 
subsequent three-strike sets. Soft-start procedures will be conducted 
any time hammering ceases for more than 30 minutes.

Monitoring and Reporting

    In order to issue an IHA for an activity, section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth ``requirements pertaining to 
the monitoring and reporting of such taking''. The MMPA implementing 
regulations at 50 CFR 216.104(a)(13) indicate that requests for IHAs 
must include the suggested means of accomplishing the necessary 
monitoring and reporting that will result in increased knowledge of the 
species and of the level of taking or impacts on populations of marine 
mammals that are expected to be present.
    Hydroacoustic monitoring will be performed at the initial 
installation of each pile driving method to ensure that the harassment 
isopleths are not extending past the calculated distances described in 
this notice and the proposed IHA (77 FR 2701, January 19, 2012) and to 
assess the efficiency of the sound attenuation devices. ORPC will 
designate two biologically-trained, on-site PSOs, approved in advance 
by NMFS, to monitor the exclusion zone (preliminarily set at 152 m [500 
ft]) for marine mammals 30 minutes before, during, and 30 minutes after 
all impact pile driving activities and call for shut down if any marine 
mammal is observed within or approaching the exclusion zone. These PSOs 
will be positioned on two vessels, one anchored upstream and one 
anchored downstream at 152 m (500 ft) on the edge of the exclusion 
zone. One observer on each vessel will survey inwards toward the pile 
driving site and the second observer will conduct behavioral monitoring 
outwards to a distance of 1 nmi during all impact pile driving. 
Additional PSOs will be stationed at the Level B harassment isopleth 
(preliminarily set at 4,600 m [2.5 mi]) on at least three days of 
vibratory pile driving to validate take estimates and evaluate the 
behavioral impacts pile driving has on marine mammals out to the Level 
B harassment isopleth.
    PSOs will be provided with the equipment necessary to effectively 
monitor for marine mammals (for example, high-quality binoculars, 
compass, and range-finder as well as a digital SLR camera with 
telephoto lens and video capability) in order to determine if animals 
have entered into the exclusion zone or Level B harassment isopleth and 
to record species, behaviors, and responses to pile driving. If 
hydroacoustic monitoring indicates that threshold isopleths are greater 
than originally calculated, ORPC will contact NMFS within 48 hours and 
make the necessary adjustments. Likewise, if threshold isopleths are 
actually less than originally calculated, downward adjustments may be 
made to the exclusion and buffer zone. PSOs will submit a report to 
NMFS within 90 days of completion of pile driving. The report will 
include data from marine mammal sightings (such as date, time, 
location, species, group size, and behavior), any observed reactions to 
construction, distance to operating pile hammer, and construction 
activities occurring at time of sighting and environmental data for the 
period (wind speed and direction, Beaufort sea state, cloud cover, and 
visibility).
    In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner prohibited by the IHA, 
such as an injury (Level A harassment), serious injury, or mortality, 
ORPC will immediately cease the specified activities and immediately 
report the incident to the Acting Chief of the Permits and Conservation 
Division, Office of Protected Resources, NMFS, at 301-427-8401 and/or 
by email to Tammy.Adams@noaa.gov and Michelle.Magliocca@noaa.gov and 
the Northeast Regional Stranding Coordinator (Mendy.Garron@noaa.gov). 
The report must include the following information:
     Time, date, and location (latitude/longitude) of the 
incident;
     Name and type of vessel involved;
     Vessel's speed during and leading up to the incident;
     Description of the incident;

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     Status of all sound source use in the 24 hrs preceding the 
incident;
     Water depth;
     Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);
     Description of all marine mammal observations in the 24 
hrs preceding the incident;
     Species identification or description of the animal(s) 
involved;
     Fate of the animal(s); and
     Photographs or video footage of the animal(s) (if 
equipment is available).
    Activities will not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS will work with ORPC to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. ORPC may not resume their 
activities until notified by NMFS via letter, email, or telephone.
    In the event that ORPC discovers an injured or dead marine mammal, 
and the lead PSO determines that the cause of the injury or death is 
unknown and the death is relatively recent (i.e., in less than a 
moderate state of decomposition as described in the next paragraph), 
ORPC will immediately report the incident to the Acting Chief of the 
Permits and Conservation Division, Office of Protected Resources, NMFS, 
at 301-427-8401, and/or by email to Tammy.Adams@noaa.gov and 
Michelle.Magliocca@noaa.gov and the Northeast Regional Stranding 
Coordinator at 978-281-9300 (Mendy.Garron@noaa.gov). The report must 
include the same information identified in the paragraph above. 
Activities may continue while NMFS reviews the circumstances of the 
incident. NMFS will work with ORPC to determine whether modifications 
in the activities are appropriate.
    In the event that ORPC discovers an injured or dead marine mammal, 
and the lead PSO determines that the injury or death is not associated 
with or related to the activities authorized in the IHA (e.g., 
previously wounded animal, carcass with moderate to advanced 
decomposition, or scavenger damage), ORPC will report the incident to 
the Acting Chief of the Permits and Conservation Division, Office of 
Protected Resources, NMFS, at 301-427-8401, and/or by email to 
Tammy.Adams@noaa.gov and Michelle.Magliocca@noaa.gov and the NMFS 
Northeast Stranding Hotline (866-755-6622) and/or by email to the 
Northeast Regional Stranding Coordinator (Mendy.Garron@noaa.gov), 
within 24 hrs of the discovery. ORPC will provide photographs or video 
footage (if available) or other documentation of the stranded animal 
sighting to NMFS and the Marine Mammal Stranding Network. Activities 
may continue while NMFS reviews the circumstances of the incident.

Estimated Take by Incidental Harassment

    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as:

    Any act of pursuit, torment, or annoyance which (i) has the 
potential to injure a marine mammal or marine mammal stock in the 
wild [Level A harassment]; or (ii) has the potential to disturb a 
marine mammal or marine mammal stock in the wild by causing 
disruption of behavioral patterns, including, but not limited to, 
migration, breathing, nursing, breeding, feeding, or sheltering 
[Level B harassment].

    Based on the application and subsequent analysis, the impact of the 
described pile driving activities, in conjunction with the required 
mitigation and monitoring measures, may result in, at most, short-term 
modification of behavior by small numbers of marine mammals within the 
action area. Marine mammals may avoid the area or temporarily alter 
their behavior at time of exposure. Current NMFS practice regarding 
exposure of marine mammals to anthropogenic noise is that in order to 
avoid the potential for injury (PTS), cetaceans and pinnipeds should 
not be exposed to impulsive sounds of 180 and 190 dB or above, 
respectively. This level is considered precautionary as it is likely 
that more intense sounds would be required before injury would actually 
occur (Southall et al., 2007). Potential for behavioral Level B 
harassment is considered to have occurred when marine mammals are 
exposed to sounds at or above 160 dB for impulse sounds (such as impact 
pile driving) and 120 dB for non-pulse noise (such as vibratory pile 
driving). These levels are also considered precautionary.
    Distances to NMFS' harassment thresholds were calculated based on 
the expected sound levels at each source and the expected attenuation 
rate of sound (see 77 FR 2701, January 19, 2012). The 100-m (328-ft) 
distance to the Level A harassment threshold provides protected species 
observers plenty of time and adequate visibility to prevent marine 
mammals from entering the area during impact pile driving. This will 
prevent marine mammals from being exposed to sound levels that reach 
the Level A harassment threshold.
    Based on ORPC's marine mammal monitoring records and the maximum 
number of pile driving days, NMFS authorized the take by Level B 
harassment of 72 total seals (because they cannot always be identified 
to the species-level), 72 harbor porpoises, and two Atlantic white-
sided dolphins. These numbers are extremely conservative and indicate 
the maximum number of animals expected to occur within the largest 
Level B harassment isopleth 4,600 m (2.5 mi). For more detailed 
information on how these numbers were calculated, see the notice of 
proposed IHA (77 FR 2701, January 19, 2012).

Negligible Impact and Small Numbers Analysis and Determination

    NMFS has defined ``negligible impact'' 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.'' In making a negligible impact determination, NMFS considers 
a number of factors which include, but are not limited to, the number 
of anticipated injuries or mortalities (none of which would be 
authorized here), number, nature, intensity, and duration of Level B 
harassment, and the context in which takes occur.
    As described above, marine mammals will not be exposed to 
activities or sound levels which could result in injury (PTS), serious 
injury, or mortality. Pile driving will occur in relatively shallow 
coastal waters of Cobscook Bay. The project area is not considered 
significant habitat for marine mammals. The closest significant 
pinniped haul out is more than six nmi away, which is well outside the 
project area's largest harassment zone. Marine mammals approaching the 
action area will likely be traveling or opportunistically foraging. The 
amount of take NMFS authorized, is considered small (less than one 
percent) relative to the estimated populations of 91,000 harbor seals, 
250,000 gray seals, 89,054 harbor porpoises, and 63,000 Atlantic white-
sided dolphins. Marine mammals may be temporarily impacted by pile 
driving noise. However, marine mammals are expected to avoid the area, 
thereby reducing exposure and impacts, and mitigation will prevent 
injury. Pile driving activities are expected to occur for about 7-12 
days total. There is no anticipated effect on annual rates of 
recruitment or survival of affected marine mammals. Based on the 
application and subsequent analysis, the impact of the described pile 
driving operations may result in, at most, short-term modification of 
behavior by small numbers of marine mammals within the action area. 
Marine mammals may avoid

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the area or temporarily alter their behavior at time of exposure.
    Based on the analysis contained in this notice, the proposed IHA 
notice (77 FR 2701, January 19, 2012), and the IHA application, and 
taking into consideration the implementation of the mitigation and 
monitoring measures, NMFS has determined that ORPC's pile driving 
activities will result in the incidental take of small numbers of 
marine mammals, by Level B harassment only, and that the total taking 
will have a negligible impact on the affected species or stocks.

Impact on Availability of Affected Species for Taking for Subsistence 
Uses

    There are no relevant subsistence uses of marine mammals implicated 
by this action.

Endangered Species Act (ESA)

    No marine mammal species listed under the ESA are anticipated to 
occur within the action area. Therefore, section 7 consultation under 
the ESA is not required.

National Environmental Policy Act (NEPA)

    In compliance with the National Environmental Policy Act of 1969 
(42 U.S.C. 4321 et seq.), as implemented by the regulations published 
by the Council on Environmental Quality (40 CFR parts 1500-1508), and 
NOAA Administrative Order 216-6, NMFS prepared an Environmental 
Assessment (EA) to consider the environmental impacts of issuance of a 
1-year IHA and made a finding of no significant impact FONSI. The EA 
and FONSI are available on the NMFS Web site listed in the beginning of 
this document (see ADDRESSES).

    Dated: March 8, 2012.
Helen M. Golde,
Deputy Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2012-6196 Filed 3-13-12; 8:45 am]
BILLING CODE 3510-22-P