[Federal Register Volume 82, Number 48 (Tuesday, March 14, 2017)]
[Notices]
[Pages 13581-13593]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-04943]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN0648-XE954
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to a Breakwater Replacement Project in
Eastport, Maine
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 regulations implementing the Marine
[[Page 13582]]
Mammal Protection Act (MMPA) as amended, notification is hereby given
that NMFS has issued an incidental harassment authorization (IHA) to
the Maine Department of Transportation (ME DOT) to incidentally harass,
by Level B harassment only, marine mammals during in-water pile driving
construction activities from the Eastport Breakwater Replacement
Project (EBRP) in Eastport, ME.
DATES: This Authorization is effective from January 24, 2017 through
January 23, 2018.
FOR FURTHER INFORMATION CONTACT: Stephanie Egger, Office of Protected
Resources, NMFS, at (301) 427-8401.
SUPPLEMENTARY INFORMATION:
Availability
An electronic copy of ME DOT's application and supporting
documents, as well as a list of the references cited in this document,
may be obtained online at www.nmfs.noaa.gov/pr/permits/incidental/construction.htm. In case of problems accessing these documents, please
call the contact listed above.
National Environmental Policy Act
NMFS prepared an Environmental Assessment (EA) in accordance with
the National Environmental Policy Act (NEPA) and considered comments
submitted in response to the Proposed IHA as part of that process.
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 by U.S.
citizens who engage in a specified activity (other than commercial
fishing) within a specified geographical region if certain findings are
made and 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 citizens of the U.S. can apply for an authorization to
incidentally take small numbers of marine mammals by harassment.
Section 101(a)(5)(D) establishes 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 August 31, 2016, we received an application from ME DOT for
authorization to take marine mammals incidental to construction
activities associated with the replacement and expansion of the pier
and breakwater in Eastport, ME. The project includes the removal of the
original filled sheet pile structure (built in 1962), the replacement
of the approach pier, expansion of the existing pier head, and the
construction of a new wave attenuator. The ME DOT submitted a revised
version of the application on October 21, 2016, and a final application
on December 2, 2016, which we deemed adequate and complete.
Harbor seal (Phoca vitulina), gray seal (Halichoerus grypus),
harbor porpoise (Phocoena phocoena), Atlantic white-sided dolphin
(Lagenorhynchus acutus) and minke whale (Balaenoptera acutorostrata)
are expected to be present during the project activities. Pile driving
activities are expected to produce in-water noise disturbance that has
the potential to result in the behavioral harassment of marine mammals.
Description of the Specified Activities
Project activities will occur in Cobscook Bay (Washington County)
in Eastport, ME. The breakwater lies near the mouth of the St. Croix
River at the end of a long peninsula adjacent to Quoddy Head. Cobscook
Bay has extremely strong tidal currents and notably high tides,
creating an extensive intertidal habitat for marine and coastal
species. Water depths at the project location are between 8 and 55 feet
(ft) (2.4--17 meter (m)). The Bay is considered a relatively intact
marine system, as the area has not experienced much industrialization.
The overall pier replacement structure consists of an open pier
supported by 151 piles, including steel pipe piles, reinforced concrete
pile caps, and a precast pre-stressed plank deck with structural
overlay. The approach pier will be 40 ft by 300 ft and the main pier
section that will be parallel to the shoreline will be 50 ft by 400 ft.
The replacement pier consists of two different sections. The
approach pier will be replaced in kind by placing fill inside of a
sheet pile enclosure, supported by driven piles. The sheet piles can be
installed by use of a vibratory hammer only. The main pier, fender
system, and wave fence system will be pile supported with piles ranging
from 16 inch (in) to 36 in diameter pipe piles. These piles will be
driven with a vibratory hammer to a point and must be seated with an
impact hammer to ensure stability. In addition, approximately 50 old
piles are expected to be removed through vibratory extraction (included
in the estimated number of project workdays). The number of piles and
types of piles needed to complete this project are described in Table
1.
Table 1--Pile Types and Amounts Required To Complete The Project
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Number of piles
Pile size and type remaining to be
installed
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16'' steel pipe pile (vibratory hammer)............. 37
20'' steel pipe pile (impact and vibratory hammer).. 25
36'' steel pipe pile (impact and vibratory hammer).. 2
[[Page 13583]]
Steel sheet pile (vibratory hammer)................. 80 pairs
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ME DOT was issued an IHA for their previous work on this project in
2014 (79 FR 59247; October 4, 2014) with a revised date for project
activities in 2015 (80 FR 46565; July 20, 2015). This prosed IHA is a
continuation of the work to complete the project that began in 2015.
A detailed description of the EBRP project is provided in the
Federal Register notice for the proposed IHA (81 FR 89066; December 12,
2016). Since that time, no changes have been made to the planned
activities. Therefore, a detailed description is not provided here.
Please refer to that Federal Register notice for the description of the
specific activity.
Comments and Responses
A notice of NMFS' proposal to issue an IHA to ME DOT was published
in the Federal Register on December 12, 2016 (81 FR 89066). That notice
described, in detail, ME DOT's activity, the marine mammal species that
may be affected by the activity, and the anticipated effects on marine
mammals. During the 30-day public comment period, NMFS received
comments from the Marine Mammal Commission (MMC). The comments are
posted online at http://www.nmfs.noaa.gov/pr/permits/incidental/construction.html. The following are the substantive comments and NMFS'
responses:
Comment 1: The MMC requested NMFS require the applicant to use a
sound attenuation device (e.g., pile cushions or confined bubble
curtain) during impact driving of steel piles.
Response: NMFS added the a mitigation measure requiring the use of
a sound attenuation device that specifically states: When using an
impact pile hammer to install piles, sound absorption cushions and/or a
bubble curtain shall be used to reduce underwater sound levels and
avoid the potential for marine mammal injury.
Comment 2: The MMC requested that for species for which
authorization has not been granted or species for which authorization
has been granted, but the authorized number of takes has already been
met, NMFS require the applicant to use delay and shut-down procedures
when individuals approach or are observed within the Level B harassment
zone.
Response: NMFS added this language to the Final IHA (see Pile
Driving Shut Down and Delay Procedures in the Mitigation section).
Comment 3: The MMC requested NMFS require the applicant use 15- and
30-min clearance times for small cetaceans and pinnipeds and large
cetaceans, respectively.
Response: In the Proposed IHA, a 30-min clearance time was proposed
for all marine mammals. We have since modified the Final IHA to use the
15- and 30-min clearance times for small cetaceans and pinnipeds and
large cetaceans, respectively.
Comment 4: The MMC requested NMFS increase the Level B harassment
takes from a total of 8 to 72 Atlantic white-sided dolphins based on
group size and frequency of occurrence.
Response: NMFS has made the recommended change from 8 dolphins to
72 based on 1 group (9 dolphins) that may enter the bay each month
(also described in the Estimated Take of Incidental Harassment
section).
Comment 5: The MMC commented on a lack of information regarding the
extent of Level A and B Harassment zones for installation of 16-, 20-
and 36-in piles using a vibratory hammer. The MMC recommended using 161
and 167 decibel (dB) source levels (SL) to calculate harassment zones.
Response: The applicant used a higher SL of 170 dB for vibratory
pile driving (accounting for both sheet piles and piles) and used the
new acoustic guidance, Technical Guidance for Assessing the Effects of
Anthropogenic Sound on Marine Mammal Hearing (July 2016), spreadsheet
(NMFS 2016) (confirmed by NMFS) to determine the permanent threshold
shift (PTS) isopleths for cetaceans and pinnipeds. The applicant then
conservatively applied this one larger shutdown zone (Level A zone) to
all cetaceans groups, using an area slightly larger than the PTS
isopleth for high-frequency cetaceans, which provides greater
protection for low- and mid-frequency cetaceans. The shutdown zone
(Level A zone) for pinnipeds is slightly larger than the PTS isopleth
calculated by the new acoustic guidance spreadsheet. Therefore, the
Level A zones calculated under the 170 dB source level are more
conservative and consider all pile sizes and sheet piles. For Level B
Harassment zones for vibratory driving of piles, NMFS used the source
levels of 161 dB and 167 dB, and used practical spreading to calculate
zones of 500 m and 1,260 m for 16-20 in and 36 in piles, respectively
(this is described in the Estimated Take of Incidental Harassment
section).
Comment 6: The MMC questioned why there were two Level B Harassment
zones (400 m and 665 m) for installation of sheet piles using a
vibratory hammer.
Response: ME DOT will install two different types of sheet piles;
therefore, two Level B Harassment zones were appropriately calculated
for monitoring. The Level B Harassment zones were calculated at 400 m
and 665 m based on the sheet pile type. Data from several sheet piles
of each pile type were used to determine the Level B zones of influence
(ZOI). The applicant indicated that the two types of sheet piles are
not usually driven simultaneously. However, if they are, the larger
Level B Harassment zone (665m) will be applied during vibratory pile
driving of sheet piles.
Comment 7: The MMC asked for clarification on whether sheet pile
removal is part of the project and if so, by which method piles will be
removed (e.g., vibratory extraction or cutting).
Response: NMFS clarified with the applicant that an estimated 50
piles will be removed using vibratory extraction. The number of
workdays includes pile removal; therefore, no revised take estimate is
needed. This information was added to the Final IHA.
Comment 8: The MMC commented that NMFS underestimated the number of
Level B harassment takes for gray/harbor seals. The MMC recommends that
NMFS use the maximum number of gray/harbor seals that were observed in
the Level B Harassment zone on a given day during the previous
authorization to inform the number of Level B harassments takes to be
authorized.
Response: In the proposed IHA, NMFS projected 120 pinnipeds per
month from January through August would be taken by Level B harassment.
This was calculated using an average group size of 6 animals per day
for a 20-day work period/month. When comparing this to ME DOT's data
collected from their previous
[[Page 13584]]
authorization, the maximum number of seals that were observed in one
month was 190 (July 2015), however; only 11 of those 190 seals were
taken as Level B harassment over a 20-day period. The average of all
seals observed in July 2015 was 10 seals per day. Therefore, NMFS has
revised the take estimate to an average of 10 seals per day, increasing
the total number of seals that may be taken by Level B harassment from
120 seals per month to 200 seals per month (also described in the
Estimated Take of Incidental Harassment section). In a previous
discussion with the applicant, ME DOT commented that in July 2015, 50
seals were observed in one monitoring day. However, the protected
species observers for ME DOT believe it was a maximum of six pinnipeds
seen multiple times that day.
Comment 9: The MMC recommended the inclusion of Level B harassment
takes for minke whales.
Response: NMFS recognizes 28 minke whales were observed during ME
DOT's previous authorization during a 4-month period (July through
October); however, none of them were observed in the Level B Harassment
zone, or thought to be taken by Level B harassment. The maximum number
of minkes that were observed was in December 2015, where 11 animals
occurred over an 18-day work period (but again, not within the
harassment zone). However, at the recommendation of the MMC to
authorize take of minke whales, NMFS will authorize 16 minke whales by
Level B harassment, assuming an average group size of two whales that
may enter the Level B Harassment zone once each month over an eight
month period.
Comment 10: The MMC suggested that ME DOT's application included
some inaccuracies and that NMFS should have worked with the applicant
more to ensure that its application was accurate and complete before
sharing it with the public and publishing the Notice of a Proposed IHA.
Response: NMFS works with applicants to ensure that applications
are accurate, as well as adequate and complete, before we develop and
publish a Notice of Proposed IHA, and we work internally to ensure that
correct and comprehensive information is included in our proposed IHAs.
In this case, in addition to working to attain this necessary quality
of documentation, we worked hard to adhere to the aggressive timeline
proposed by the applicant in order to support their important and time-
sensitive work on this project. We will continue to ensure that the
information we rely on for our decisions is based on the best available
information and strive to conduct our regulatory processes in a timely
manner that supports applicants' needs.
Description of Marine Mammals in the Area of the Specified Activity
The marine mammal species under NMFS jurisdiction authorized for
incidental Level B take as a result of project activities, are the
harbor seal, gray seal, harbor porpoise, Atlantic white-sided dolphin
and minke whale (Table 2).
Table 2--Marine Mammal Information for the Project Area
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Stock abundance (CV,
ESA/MMPA status; Nmin, most recent Annua M/ Relative occurrence/season
Species Stock strategic (Y/N) \1\ abundance survey) PBR \3\ SI \4\ of occurrence
\2\
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Harbor seal....................... Western North -; N 75,834 (0.15; 66,884; 2,006 420 Harbor seals are year-
Atlantic. 2012). round inhabitants of the
coastal waters of Maine
and eastern Canada.
Gray seal......................... Western North -; N unknown 505,000 (best unknown 5,004 Gray seals currently pup
Atlantic. estimate 2014 at two established
Canadian population colonies in Maine: Green
DFO 2014). and Seal Islands.
Harbor porpoise................... Gulf of Maine/Bay of -; N 79,883 (0.32; 61,415; 706 564 During winter (January to
Fundy. 2011). March), intermediate
densities of harbor
porpoises can be found in
waters off New York to New
Brunswick, Canada.
In spring (April-June),
harbor porpoises are
widely
dispersed from ME to NJ,
with lower densities
farther north and south.
Atlantic white-sided dolphin...... Western North -; N 48,819 (0.61; 30,403; 304 102 During January to May, low
Atlantic. 2011). numbers of white-sided
dolphins are found from
Georges Bank (separates
the Gulf of Maine from
the Atlantic Ocean to
Jeffreys Ledge (in the
Western Gulf of Maine off
of New Hampshire).
Minke whale....................... Canadian East Coast.. -; N 20,741 (0.30; 16,199; 162 7.9 During the spring and
2007). fall, minkes are
relatively widespread and
common and when the
whales are most abundant
in New England waters.
During the winter, minkes
appears to be largely
absent.
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\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
exceeds PBR (see footnote 3) or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species
or stock listed under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
[[Page 13585]]
\2\ CV is coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable. For certain stocks of
pinnipeds, abundance estimates are based upon observations of animals (often pups) ashore multiplied by some correction factor derived from knowledge
of the species (or similar species) life history to arrive at a best abundance estimate; therefore, there is no associated CV. In these cases, the
minimum abundance may represent actual counts of all animals ashore. The most recent abundance survey that is reflected in the abundance estimate is
presented; there may be more recent surveys that have not yet been incorporated into the estimate.
\3\ Potential biological removal, defined by the MMPA as the maximum number of animals, not including natural mortalities, that may be removed from a
marine mammal stock while allowing that stock to reach or maintain its optimum sustainable population size (OSP).
\4\ These values, found in NMFS' SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g., commercial
fisheries, subsistence hunting, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value.
A detailed description of the species likely to be affected by the
EBRP, including brief introductions to the species and relevant stocks
as well as available information regarding population trends and
threats, and information regarding local occurrence, were provided in
the Federal Register notice for the proposed IHA (81 FR 89066; December
12, 2016) (with the exception of the minke whale that has been added to
this Final IHA). Since that time, we are not aware of any changes in
the status of these species and stocks that were previously described
in the proposed IHA; therefore, detailed descriptions are not provided
here. Please refer to that Federal Register notice for these
descriptions. Please also refer to NMFS' Web site (www.nmfs.noaa.gov/pr/species/mammals/) for generalized species accounts.
Minke whale
The minke whale is common and widely distributed within the U.S.
Atlantic Exclusive Economic Zone (EEZ) (CETAP 1982 as cited in Waring
et al., 2015). During the spring to fall, minkes are relatively
widespread and common occurrence, and when the whales are most abundant
in New England waters. However, during winter months, minkes appear to
be largely absent (e.g., Risch et al., 2013 as cited as Waring et al.,
2015). Like most other baleen whales, minke whales generally occupy the
continental shelf proper (< 100 m deep), rather than the continental
shelf-edge region (Waring et al., 2015). In the North Atlantic, there
are four recognized populations--Canadian East Coast, west Greenland,
central North Atlantic, and northeastern North Atlantic (Donovan 1991
as cited in Waring et al., 2015). Minke whales off the eastern coast of
the United States are considered to be part of the Canadian East Coast
stock, which inhabits the area from the western half of the Davis
Strait (45[deg] W.) to the Gulf of Mexico (Waring et al., 2015). The
most current abundance estimate for minke whales is 20,741. A current
population trend analysis has not been conducted for this stock (Waring
et al., 2015).
Effects of the Specified Activity on Marine Mammals and Their Habitat
In-water construction activities associated with the EBRP such as
impact and vibratory pile driving components of the specified activity
have the potential to result in impacts to marine mammals and their
habitat in the project area. The Federal Register notice for the
proposed IHA (81 FR 89066; December 12, 2016) included a detailed
discussion of the behavioral and acoustic effects on marine mammals.
Therefore, that information is not repeated here. Please refer to the
referenced Federal Register notice for that information. No take by
injury, serious injury, or death is anticipated as a result of the
construction activities.
Mitigation
In order to issue an IHA for the 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
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. NMFS regulations require
applicants for incidental take authorizations to include information
about the availability and feasibility (economic and technological) of
equipment, methods, and manner of conducting such activity or other
means of effecting the least practicable adverse impact upon the
affected species or stocks, their habitat (50 CFR 216.104(a)(11)).
ME DOT worked with NMFS and developed the following mitigation
measures to minimize the potential impacts to marine mammals in the
project vicinity. The primary purposes of these mitigation measures are
to minimize sound levels from the activities, and to monitor marine
mammals within designated ZOI corresponding to NMFS' current Level A
and B harassment thresholds. Here we provide a description of the
mitigation measures required as part of the Authorization.
Noise Attenuation Devices
When using an impact hammer to ``proof'' piles, ME DOT shall use
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.
Zones of Influence
Direct measured data from the pile driving events of the EBRP IHA
were used to calculate the ZOIs for Level B Harassment for pile driving
activities. These values were used to develop mitigation measures for
pile driving activities at EBRP. The ZOIs effectively represent the
mitigation zone that will be established around each pile to prevent
Level A harassment to marine mammals, while providing estimates of the
areas within which Level B harassment might occur. In addition to the
specific measures described later in this section, the EBRP will
conduct briefings between construction supervisors and crews, marine
mammal monitoring team, and EBRP staff prior to the start of all pile
driving activity, and if/when new personnel join the work, in order to
explain responsibilities, communication procedures, marine mammal
monitoring protocol, and operational procedures.
Monitoring and Shutdown for Pile Driving
The following measures will apply to the EBRP's mitigation through
shutdown and disturbance zones:
Shutdown Zone--For all pile driving activities, EBRP will establish
exclusion zones (shutdown zones). Shutdown zones are intended to
contain the area in which SPLs equal or exceed acoustic injury
criteria, with the purpose being to define an area within which
shutdown of activity will occur upon sighting of a marine mammal (or in
anticipation of an animal entering the defined area), thus preventing
injury marine mammals (PTS) of marine mammals (as described previously
under Potential Effects of the Specified Activity on Marine Mammals,
serious injury or death are unlikely outcomes even in the absence of
mitigation measures).
[[Page 13586]]
Using the user spreadsheet for the NMFS new acoustic guidance,
injury zones were determined for low-, mid- and high-frequency
cetaceans and pinnipeds (phocids) as the hearing groups analyzed for
this project (see Table 3). The purpose of a shutdown zone is to define
an area within which shutdown of activity will occur upon sighting of a
marine mammal (or in anticipation of an animal entering the defined
area). As a precautionary measure, intended to reduce the unlikely
possibility of injury from direct physical interaction with
construction operations, ME DOT will implement a minimum shutdown zone
of 10 m radius around each pile for all construction methods for all
marine mammals. The shutdown zones calculated for injury were rounded
to the nearest 10 m to be more conservative or species were grouped
(e.g., low-, mid- and high-frequency cetaceans combined into one group)
for more streamlined monitoring in the field. For both impact and
vibratory pile driving, the shutdown zones were increased for low- and
mid-frequency cetaceans to that which was calculated for high-frequency
cetaceans in order to group all cetaceans together for monitoring. The
shutdown zones for vibratory pile driving were calculated considering
all piles (sheet piles and piles) and are more conservative for piles
as their source levels are lower than the one entered into the
spreadsheet for sheet piles.
Table 3--Injury Zones and Shutdown Zones for Hearing Groups for Each Construction Method
----------------------------------------------------------------------------------------------------------------
High-
Hearing group Low-frequency Mid-frequency frequency Phocid
cetaceans (m) cetaceans (m) cetaceans (m) pinnipeds (m)
----------------------------------------------------------------------------------------------------------------
Vibratory Pile Driving \1\
----------------------------------------------------------------------------------------------------------------
PTS Isopleth to threshold....................... 79.5 7.0 117.5 48.3
------------------------------------------------
Shutdown Zone................................... 120 50
----------------------------------------------------------------------------------------------------------------
Impact Pile Driving \2\
----------------------------------------------------------------------------------------------------------------
PTS Isopleth to threshold....................... 130.7 4.6 155.6 69.9
------------------------------------------------
Shutdown Zone................................... 160 70
----------------------------------------------------------------------------------------------------------------
\1\ For vibratory driving, SL is 170 dB, TL is15logR, weighting function is 2.5, duration is 5 hours, and
distance from the source is 10 m. This covers all vibratory hammering.
\2\ For impact driving, SL (Single Strike/shot SEL) is 171 dB, TL is 15log R, weighting function is 2, strikes
per pile is 250, number off piles per day is 3, and distance from the source is 10 m.
Disturbance Zone--Disturbance zones are the areas in which SPLs
equal or exceed 160 and 120 dB rms (for impulse and continuous sound,
respectively). Disturbance zones provide utility for monitoring
conducted for mitigation purposes (i.e., shutdown zone monitoring) by
establishing monitoring protocols for areas adjacent to the shutdown
zones. Monitoring of disturbance zones enables observers to be aware of
and communicate the presence of marine mammals in the project area but
outside the shutdown zone and thus prepare for potential shutdowns of
activity. However, the primary purpose of disturbance zone monitoring
is for documenting incidents of Level B harassment; disturbance zone
monitoring is discussed in greater detail later (see Monitoring and
Reporting). Any marine mammal documented within the Level B harassment
zone will constitute a Level B take (harassment), and will be recorded
and reported as such. Nominal radial distances for disturbance zones
are shown in Table 4. Given the size of the disturbance zone for both
impact and vibratory pile driving, it is impossible to guarantee that
all animals will be observed or to make comprehensive observations of
fine-scale behavioral reactions to sound, and only a portion of the
zone (e.g., what may be reasonably observed by visual observers) would
be observed.
Table 4--Calculated Threshold Distances (m) for Level B Harassment of Marine Mammals
----------------------------------------------------------------------------------------------------------------
Threshold distances (m)
Source -----------------------------------------------------------------------
160 dB (m) 120 dB
----------------------------------------------------------------------------------------------------------------
Vibratory pile driving.................. n/a 400 m for PZC-18 Sheet Piles.
665 m for PZC-26 Sheet Piles.
500 m for 16-20 in piles.
1,260 m for 36 in piles.
Impact pile driving..................... 550 n/a.
----------------------------------------------------------------------------------------------------------------
Note: If both types of sheet piles were installed simultaneously, the larger Level B zone of 665 m will be used.
In order to document observed incidents of harassment, monitors
will record all marine mammal observations, regardless of location. The
observer's location, as well as the location of the pile being driven
or removed, is known from a GPS unit. The location of the animal is
estimated as a distance from the observer, which is then compared to
the location from the pile. It may then be estimated whether the animal
was exposed to sound levels constituting incidental harassment on the
basis of predicted distances to relevant thresholds in post-processing
of observational and acoustic data, and a precise accounting of
observed incidences of harassment created. This information may then be
used to extrapolate observed takes to reach an
[[Page 13587]]
approximate understanding of actual total takes.
Two Qualified Protected Species Observers (PSO) (NMFS approved
biologists, monitoring responsibilities fully described in the
Monitoring section) will be stationed on the pier. One PSO will be
responsible for monitoring the shutdown zones, while the second
observer will conduct behavioral monitoring outwards to a distance of 1
nautical mile (nmi).
Pile Driving Shut Down and Delay Procedures
If a PSO sees a marine mammal within or approaching the shutdown
zones prior to start of 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 out of
the shutdown zone from the sound source or if the animal has not been
resighted within 15 min for small cetaceans and pinnipeds and 30 min
for large cetaceans. If a marine mammal is sighted within or on a path
toward a shutdown zone during pile driving, pile driving will cease
until that animal has moved out of the shutdown zone and is on a path
away from the shutdown zone or 15 min (pinnipeds and small cetaceans)/
30 min (large cetaceans) has lapsed since the last sighting. Shutdown
and delay procedures will also be required if a species for which
authorization has not been granted or if a species for which
authorization has been granted but the authorized number of takes has
been met, approaches or is observed within the Level B harassment zone.
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-min waiting period. The
procedure will be repeated two additional times before full energy may
be achieved. For impact pile driving, contractors will be required to
provide an initial set of 3 strikes from the impact hammer at 40
percent energy, followed by a 1-min waiting period, then two subsequent
3 strike sets. Soft-start procedures will be conducted any time
hammering ceases for more than 30 min.
Time Restrictions
Work will occur only during daylight hours, when visual monitoring
of marine mammals can be conducted.
Mitigation Conclusions
To ensure that the ``least practicable adverse impact'' will be
achieved, NMFS has carefully evaluated mitigation measures in
consideration of the following factors in relation to one another: The
manner in which, and the degree to which, the successful implementation
of the measure(s) is expected to reduce impacts to marine mammals,
marine mammal species or stocks, their habitat, and their availability
for subsistence uses (latter where relevant); the proven or likely
efficacy of the measures; and the practicability of the measures for
applicant implementation (including, consideration of personnel safety,
practicality of implementation).
Any mitigation measure(s) prescribed by NMFS should be able to
accomplish, have a reasonable likelihood of accomplishing (based on
current science), or contribute to the accomplishment of one or more of
the general goals listed below:
1. Avoidance or minimization of injury or death of marine mammals
wherever possible (goals 2, 3, and 4 may contribute to this goal).
2. A reduction in the numbers of marine mammals (total number or
number at biologically important time or location) exposed to received
levels of pile driving, or other activities expected to result in the
take of marine mammals (this goal may contribute to 1, above, or to
reducing harassment takes only).
3. A reduction in the number of times (total number or number at
biologically important time or location) individuals would be exposed
to received levels of pile driving, or other activities expected to
result in the take of marine mammals (this goal may contribute to 1,
above, or to reducing harassment takes only).
4. A reduction in the intensity of exposures (either total number
or number at biologically important time or location) to received
levels of pile driving, or other activities expected to result in the
take of marine mammals (this goal may contribute to 1, above, or to
reducing the severity of harassment takes only).
5. Avoidance or minimization of adverse effects to marine mammal
habitat, paying special attention to the food base, activities that
block or limit passage to or from biologically important areas,
permanent destruction of habitat, or temporary destruction/disturbance
of habitat during a biologically important time.
6. For monitoring directly related to mitigation--an increase in
the probability of detecting marine mammals, thus allowing for more
effective implementation of the mitigation.
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
incidental take authorizations 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 in the project action area.
Any monitoring requirement we prescribe should improve our
understanding of one or more of the following:
Occurrence of marine mammal species in the action area
(e.g., presence, abundance, distribution, density).
Nature, scope, or context of likely marine mammal exposure
to potential stressors/impacts (individual or cumulative, acute or
chronic), through better understanding of: (1) Action or environment
(e.g., source characterization, propagation, ambient noise); (2)
Affected species (e.g., life history, dive patterns); (3) Co-occurrence
of marine mammal species with the action; or (4) Biological or
behavioral context of exposure (e.g., age, calving or feeding areas).
Individual responses to acute stressors, or impacts of
chronic exposures (behavioral or physiological).
How anticipated responses to stressors impact either: (1)
Long-term fitness and survival of an individual; or (2) population,
species, or stock.
Effects on marine mammal habitat and resultant impacts to
marine mammals.
Mitigation and monitoring effectiveness.
Visual Marine Mammal Observations
PSOs shall be used to detect, document, and minimize impacts to
marine mammals. Monitoring will be conducted before, during, and after
construction activities. In addition, PSOs shall record all incidents
of marine mammal occurrence, regardless of distance from activity, and
document any behavioral reactions in concert with
[[Page 13588]]
distance from construction activities. Important qualifications for
PSOs for visual monitoring include:
Visual acuity in both eyes (correction is permissible)
sufficient for discernment of marine mammals on land or in the water
with ability to estimate target size and distance; use of binoculars
may be necessary to correctly identify the target;
Advanced education in biological science or related field
(undergraduate degree or higher required);
Experience and ability to conduct field observations and
collect data according to assigned protocols (this may include academic
experience);
Experience or training in the field identification of
marine mammals, including the identification of behaviors;
Sufficient training, orientation, or experience with the
construction operation to provide for personal safety during
observations;
Writing skills sufficient to prepare a report of
observations including but not limited to the number and species of
marine mammals observed; dates and times when construction activities
were conducted; dates and times when construction activities were
suspended, if necessary; and marine mammal behavior; and
Ability to communicate orally, by radio or in person, with
project personnel to provide real-time information on marine mammals
observed in the area as necessary.
PSOs shall also conduct mandatory biological resources awareness
training for construction personnel. The awareness training shall be
provided to brief construction personnel on marine mammals and the need
to avoid and minimize impacts to marine mammals. If new construction
personnel are added to the project, the contractor shall ensure that
the personnel receive the mandatory training before starting work. PSOs
will have authority to stop construction if marine mammals appear
distressed (evasive maneuvers, rapid breathing, inability to flush) or
in danger of injury.
The ME DOT has developed a monitoring plan based on discussions
between ME DOT and NMFS. The ME DOT will collect sighting data and
behavioral responses to construction activities for marine mammal
species observed in the region of activity during the period of
activity. All PSOs will be trained in marine mammal identification and
behaviors and are required to have no other construction-related tasks
while conducting monitoring.
Data Collection
We require that PSOs use approved data forms. Among other pieces of
information, the ME DOT will record detailed information about any
implementation of shutdowns, including the distance of animals to the
pile and description of specific actions that ensued and resulting
behavior of the animal, if any. In addition, the ME DOT will attempt to
distinguish between the number of individual animals taken and the
number of incidents of take. We require that, at a minimum, the
following information be collected on the sighting forms:
Date and time that monitored activity begins or ends;
Construction activities occurring during each observation
period;
Weather parameters (e.g., percent cover, visibility);
Water conditions (e.g., sea state, tide state);
Species, numbers, and, if possible, sex and age class of
marine mammals;
Description of any observable marine mammal behavior
patterns, including bearing and direction of travel and distance from
pile driving activity;
Distance from pile driving activities to marine mammals
and distance from the marine mammals to the observation point;
Locations of all marine mammal observations; and
Other human activity in the area.
Reporting
ME DOT is required to submit a draft monitoring report to NMFS
within 90 days of completion of in-water construction activities. The
report will include data from marine mammal sightings as described in
the Data Collection section above (i.e., 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
(i.e., wind speed and direction, sea state, tidal 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
(if issued), such as an injury (Level A harassment), serious injury, or
mortality, ME DOT will immediately cease the specified activities and
immediately report the incident to the Permits and Conservation
Division, Office of Protected Resources, NMFS and the Greater Atlantic
Regional Fisheries Office Stranding Coordinator. 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;
Status of all sound source use in the 24 hrs preceding the
incident;
Water depth;
Environmental conditions (e.g., wind speed and direction,
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 ME DOT to
determine what is necessary to minimize the likelihood of further
prohibited take and ensure MMPA compliance. ME DOT may not resume their
activities until notified by NMFS via letter, email, or telephone.
In the event that ME DOT 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),
ME DOT will immediately report the incident to the NMFS' Permits and
Conservation Division, Office of Protected Resources at (301) 427-840
and NMFS' GARFO Stranding Coordinator at (978) 282-8478. 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 ME DOT to determine whether modifications
in the activities are appropriate.
In the event that ME DOT 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), ME DOT will report the incident to
the NMFS' Permits and Conservation Division, Office of Protected
Resources at (301) 427-840 and the NMFS' GARFO Stranding Coordinator at
(978) 282-8478 within 24 hrs of the discovery. ME DOT 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
[[Page 13589]]
may continue while NMFS reviews the circumstances of the incident.
Estimated Take of Incidental Harassment
Except with respect to certain activities not pertinent here,
section 3(18) of 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).''
All anticipated takes will be by Level B harassment resulting from
pile driving activities involving temporary changes in behavior. The
mitigation and monitoring measures are expected to minimize the
possibility of injurious or lethal takes such that potential for take
by Level A harassment, serious injury, or mortality is considered
discountable.
Given the many uncertainties in predicting the quantity and types
of impacts of sound on marine mammals, it is common practice to
estimate take based on how many animals are likely to be present within
a particular distance of a given activity, or exposed to a particular
level of sound. In practice, depending on the amount of information
available to characterize daily and seasonal movement and distribution
of affected marine mammals, it can be difficult to distinguish between
the number of individuals harassed and the instances of harassment and,
when duration of the activity is considered, it can result in a take
estimate that overestimates the number of individuals harassed. In
particular, for stationary activities, it is more likely that some
smaller number of individuals may accrue a number of incidences of
harassment per individual than for each incidence to accrue to a new
individual, especially if those individuals display some degree of
residency or site fidelity and the impetus to use the site (e.g.,
because of foraging opportunities) is stronger than the deterrence
presented by the harassing activity.
Elevated in-water sound levels from pile driving activities in the
project area may temporarily impact marine mammal behavior. Elevated
in-air sound levels are not a concern because the nearest significant
pinniped haul-out is more than six nmi away. 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).
Behavioral disturbances that could result from anthropogenic sound
associated with these activities are expected to affect only a small
number of individual marine mammals, although those effects could be
recurring over the life of the project if the same individuals remain
in the project vicinity.
The ME DOT has requested authorization for the incidental taking of
small numbers of harbor seals, gray seals, harbor porpoise, Atlantic
white-sided dolphins, and minke whales incidental to the pile driving
associated with the EBRP described previously in this document. In
order to estimate the potential incidents of take that may occur
incidental to the specified activity, we must first estimate the extent
of the sound field that may be produced by the activity and then
consider in combination with information about marine mammal density or
abundance in the project area and the number of days the activity will
be conducted. We first provide information on applicable sound
thresholds for determining effects to marine mammals before describing
the information used in estimating the sound fields, the available
marine mammal density or abundance information, and the method of
estimating potential incidents of take.
As discussed above, in-water pile driving activities generate loud
noises that could potentially harass marine mammals in the vicinity of
ME DOT's EBRP. No impacts from visual disturbance are anticipated
because there are no known pinniped haul-outs within the project area.
The only potential disturbance anticipated to occur will be during
driving operations, which may cause individual marine mammals to
temporarily avoid the area.
Sound Thresholds
We use generic sound exposure thresholds to determine when an
activity that produces sound might result in impacts to a marine mammal
such that a take by Level B harassment might occur. To date, no studies
have been conducted that explicitly examine impacts to marine mammals
from pile driving sounds or from which empirical sound thresholds have
been established. These thresholds (Table 5) are used to estimate when
harassment may occur (i.e., when an animal is exposed to levels equal
to or exceeding the relevant criterion) in specific contexts; however,
useful contextual information that may inform our assessment of effects
is typically lacking and we consider these thresholds as step
functions. NMFS new technical guidance establishes new thresholds for
predicting auditory injury, which equates to Level A harassment under
the MMPA. The ME DOT project used this new technical guidance when
determining the injury (Level A) zones (see Table 3).
Table 5--Current Acoustic Exposure Criteria for Level B Harassment
------------------------------------------------------------------------
Criterion Definition Threshold
------------------------------------------------------------------------
Level B harassment Behavioral 160 dB (impulsive
(underwater) \1\. disruption. source)/120 dB
(continuous source).
Level B harassment (airborne) Behavioral 90 dB (harbor seals)/
\2\. disruption. 100 dB (other
pinnipeds)
(unweighted).
------------------------------------------------------------------------
Note: All thresholds are based off of root mean square (rms) levels.
\1\ All decibels referenced to 1 micro Pascal (re: 1uPa).
\2\ All decibels referenced to 20 micro Pascals (re: 20uPa).
[[Page 13590]]
Distance to Sound Thresholds
Pile driving generates underwater noise that can potentially result
in disturbance to marine mammals in the project area. Transmission loss
(TL) is the decrease in acoustic intensity as an acoustic pressure wave
propagates out from a source. TL parameters vary with frequency,
temperature, sea conditions, current, source and receiver depth, water
depth, water chemistry, and bottom composition and topography. The
general formula for underwater TL is:
TL = B * log10(R1/R2),
Where:
R1 = the distance of the modeled SPL from the driven
pile, and
R2 = the distance from the driven pile of the initial
measurement.
This formula neglects loss due to scattering and absorption, which
is assumed to be zero here. The degree to which underwater sound
propagates away from a sound source is dependent on a variety of
factors, most notably the water bathymetry and presence or absence of
reflective or absorptive conditions including in-water structures and
sediments. Spherical spreading occurs in a perfectly unobstructed
(free-field) environment not limited by depth or water surface,
resulting in a 6 dB reduction in sound level for each doubling of
distance from the source (20*log[range]). Cylindrical spreading occurs
in an environment in which sound propagation is bounded by the water
surface and sea bottom, resulting in a reduction of 3 dB in sound level
for each doubling of distance from the source (10*log[range]). A
practical spreading value of fifteen is often used under conditions,
where water increases with depth as the receiver moves away from the
shoreline, resulting in an expected propagation environment that would
lie between spherical and cylindrical spreading loss conditions.
For Level B ZOIs for vibratory driving of piles, NMFS used source
levels of 161 dB and 167 dB, and used practical spreading to calculate
zones of 500 m and 1,260 m for 16-20 in and 36-in piles, respectively.
In this case of sheet piles, we have measured field data available
from the previous EBRP IHA at the same location and from the same type
sheet piles showing at a particular point where the received level is
below 120 dB, to determine the disturbance distance for the Level B
ZOI. Data from several sheet piles of each pile type were used to
determine the Level B ZOIs. For sheet pile type PZC-18, 400 m is the
measured distance where the Level B ZOI is below 120 dB. For sheet pile
type PZC-26, the farthest measurement did not go below 120 dB so the
statistical analysis of 90 percent confidence interval was used, which
pointed to 665 m for the Level B ZOI. For impact pile driving, we used
the third farthest point from the measured field data, which was 550 m
from the source, and measured under 160 dB.
The sound field in the project area is the existing ambient noise
plus additional construction noise from the project. The primary
components of the project expected to affect marine mammals is the
sound generated by impact and vibratory pile driving. The intensity of
pile driving sounds is greatly influenced by factors such as the type
of piles, hammers, and the physical environment in which the activity
takes place. In order to determine the distance to the thresholds and
the received levels to marine mammals that are likely to result from
pile driving at EBRP, we evaluated the acoustic monitoring data (Table
6) from the previous EBRP IHA with similar properties to the current
project activity.
Table 6--Eastport Breakwater Noise Monitoring Data for Un-Attenuated
Pile Strikes With an Impact Hammer and a Vibratory Hammer
------------------------------------------------------------------------
Relative water
Pile type/size depth (m) Max avg dB RMS
------------------------------------------------------------------------
Impact Pile Driving
------------------------------------------------------------------------
20 ft/Steel Pipe................ 15 182.
20 ft/Steel Pipe (`Spin fin')... 15 186.
------------------------------------------------------------------------
Vibratory Pile Driving
------------------------------------------------------------------------
24 ft Steel Sheet PZC-16........ 15 170 (max dB RMS).
------------------------------------------------------------------------
We consider the values presented in Table 6 to be representative of
SPLs that may be produced by pile driving in the project area.
Distances to the harassment isopleths vary by marine mammal type and
pile extraction/driving tool. All calculated distances to and the total
area encompassed by the marine mammal sound thresholds are provided in
Tables 3 and 4.
In addition, we generally recognize that pinnipeds occurring within
an estimated airborne harassment zone, whether in the water or hauled
out (no haul outs within six nmi of the project area), could be exposed
to airborne sound that may result in behavioral harassment. However,
any animal exposed to airborne sound above the behavioral harassment
threshold is likely to also be exposed to underwater sound above
relevant thresholds (which are typically in all cases larger zones than
those associated with airborne sound). Thus, the behavioral harassment
of these animals is already accounted for in the estimates of potential
take. Multiple incidents within a day of exposure to sound above NMFS'
thresholds for behavioral harassment are not believed to result in
increased behavioral disturbance, in either nature or intensity of
disturbance reaction. Therefore, we do not believe that authorization
of incidental take resulting from airborne sound for pinnipeds is
warranted, and airborne sound is not discussed further here.
Acoustic Impacts
When considering the influence of various kinds of sound on the
marine environment, it is necessary to understand that different kinds
of marine life are sensitive to different frequencies of sound. Based
on available behavioral data, audiograms have been derived using
auditory evoked potentials, anatomical modeling, and other data.
Southall et al. (2007) designated hearing groups for marine mammals and
estimated the lower and upper frequencies of hearing of the groups.
NMFS made modifications to
[[Page 13591]]
the marine mammal hearing groups proposed in Southall et al. (2007)
which is reflected in the new technical guidance (NMFS 2016). The
marine mammal hearing groups, pinnipeds, high frequency cetaceans
(harbor porpoise), mid-frequency cetaceans (Atlantic white-sided
dolphin) and low-frequency cetaceans (minke whale) which are the
subject of this project, and their associated generalized hearing range
were previous discussed in the Marine Mammal Hearing section.
As mentioned previously in this document, five marine mammal
species (three cetacean and two pinniped species) are likely to occur
in the area of the activity. Of the three cetacean species likely to
occur in the project area, the minke whale is considered a low-
frequency cetacean, the Atlantic white-sided dolphin is classified as a
mid-frequency cetacean and the harbor porpoise is classified as a high-
frequency cetacean (NMFS 2016). A species' hearing group and its
generalized hearing range is a consideration when we analyze the
effects of exposure to sound on marine mammals.
ME DOT and NMFS determined that in-water construction activities
involving the use of impact and vibratory pile driving during the EBRP
has the potential to result in behavioral harassment of marine mammal
species and stocks in the vicinity of the project activity.
Description of Take Calculation
The following sections are descriptions of how take was determined
for impacts to marine mammals from noise disturbance related to pile
driving.
Incidental take is calculated for each species by estimating the
likelihood of a marine mammal being present within the ensonified area
above the threshold during pile driving activities, based on
information about the presence of the animal (density estimates or the
best available occurrence data) and the size of the zones of influence,
which in this case is based on previous measurements from the acoustic
monitoring in the previous EBRP IHA. Expected marine mammal presence is
determined by past observations and general abundance during the
construction window. When local abundance is the best available
information, in lieu of the density-area method, we may simply multiply
some number of animals (as determined through counts of animals hauled-
out) by the number of days of activity, under the assumption that all
of those animals will be present within the area ensonified by the
threshold and incidentally taken on each day of activity.
There are a number of reasons why estimates of potential incidents
of take may be conservative, assuming that available density or
abundance estimates and estimated ZOI areas are accurate. We assume, in
the absence of information supporting a more refined conclusion, that
the output of the calculation represents the number of individuals that
may be taken by the specified activity. In fact, in the context of
stationary activities such as pile driving and in areas where resident
animals may be present, this number more realistically represents the
number of incidents of take that may accrue to a smaller number of
individuals. While pile driving can occur any day throughout the in-
water work window, and the analysis is conducted on a per day basis,
only a fraction of that time (typically a matter of hours on any given
day) is actually spent pile driving. The potential effectiveness of
mitigation measures in reducing the number of takes is typically not
quantified in the take estimation process. For these reasons, these
take estimates may be conservative.
For this project, the take requests were estimated using local
marine mammal data sets and information from Federal agencies and other
experts. The best available data for marine mammals in the vicinity of
the project area was derived from three sources including: three years
(2007-2010) of marine mammal monitoring data from the Ocean Renewable
Power Company (ORPC) tidal generator project that was located between
Eastport and Lubec, ME, the 2015-2016 marine mammal monitoring data
from the previous EBRP IHA, and communication with marine mammals
experts from ME (Stephanie Wood (NOAA Biologist) and Dr. James Gilbert
(Wildlife Ecologist, University of ME)). Although the ORPC project was
located on the other side of the peninsula from the Eastport pier, the
presence of species and timing of their occurrence appears similar
between the ORPC data and marine mammal monitoring data from the
previous EBRP IHA.
The calculation for marine mammal exposures is estimated by:
Exposure estimate = N (number of animals in the area that is ensonified
above the thresholds based on the previous sound measurements) * 160
days of pile driving activities from January to August 2017.
The estimated number of animals in the area was previously
determined based on the maximum group size of animals observed during
ORPC's marine mammal observation effort (six seals (harbor and gray
seals combined), six harbor porpoises, and one Atlantic white-sided
dolphin) multiplied by the maximum expected number of pile/sheet
installation and sheet removal days. During the winter and spring
months we expect lower numbers of harbor porpoise in the Gulf of Maine
(including the project area) and therefore take estimates were lower
(January through May). Atlantic white-sided dolphins are not expected
to frequent the project area, as they are more of a pelagic species.
Only two Atlantic white-sided dolphins were observed in four years of
marine mammal monitoring (ORPC and EBRP IHA). Harbor and gray seals
were combined into one pinniped group because they cannot always be
identified by species level. See Tables 7 and 8 for total estimated
incidents of take.
Based on comments provided by the MMC, take estimates are now
revised for gray/harbor seal and Atlantic white-side dolphins. Minke
whale take has also been added. In the proposed IHA, NMFS estimated 120
pinnipeds per month from January through August would be taken by Level
B Harassment. This was calculated using an average group size of six
animals per day for a 20-day work period/month. When comparing this to
ME DOT's data collected from their previous authorization, the maximum
number of seals observed in one month was 190 (July 2015), however;
only 11 of those 190 seals were taken as Level B harassment over a 20-
day period. The average of all seals observed in July 2015 was 10 seals
per day. Therefore, NMFS has revised the take estimate to an average of
10 seals per day, increasing the total number of seals that may be
taken by Level B harassment from 120 seals to 200 seals per month
(Table 7). Although only two Atlantic white-sided dolphins were
observed over the past four years, NMFS has revised the Level B take
estimate, recommended by the MMC, from one Atlantic white-sided
dolphins per month to nine dolphins per month based on one group (nine
dolphins) that may enter the bay each month. NMFS added minke whales to
be taken by Level B Harassment over the project period. NMFS recognizes
28 minke whales were observed during ME DOT's previous authorization
during a 4-month period (July through October); however, none of these
whales were taken by Level B harassment. The
[[Page 13592]]
maximum number of minkes observed was in December 2015, where 11
animals occurred over an 18-day work period. NMFS will authorize 16
minke whales may be taken by Level B Harassment assuming a group size
of two whales may enter the Level B Harassment zone each month over an
eight month period.
Table 7--Marine Mammal Calculated Take for Level B Harassment
--------------------------------------------------------------------------------------------------------------------------------------------------------
Calculated
Calculated Calculated Atlantic white- Calculated minke
Month Pile driving harbor/gray seal harbor porpoise sided dolphin whale take by
days per month take by Level B take by Level B take by Level B Level B
Harassment Harassment Harassment Harassment
--------------------------------------------------------------------------------------------------------------------------------------------------------
Jan........................................................... 20 200 6 9 2
Feb........................................................... 20 200 6 9 2
March......................................................... 20 200 6 9 2
April......................................................... 20 200 6 9 2
May........................................................... 20 200 6 9 2
June.......................................................... 20 200 120 9 2
July.......................................................... 20 200 120 9 2
August........................................................ 20 200 120 9 2
Sept.......................................................... ................ ................ ................ ................ ................
Oct........................................................... ................ ................ ................ ................ ................
Nov........................................................... ................ ................ ................ ................ ................
Dec........................................................... ................ ................ ................ ................ ................
-----------------------------------------------------------------------------------------
Total..................................................... 160 1,600 390 72 16
--------------------------------------------------------------------------------------------------------------------------------------------------------
Table 8--Estimated Marine Mammal Takes by Level B Harassment
----------------------------------------------------------------------------------------------------------------
Approximate
percentage of
Species Take Abundance estimated stock Population trend
authorization (takes authorized/
population)
----------------------------------------------------------------------------------------------------------------
Harbor seal *............... 1,600 75,834--Western North 2.11 unknown.
Atlantic stock.
Gray seal................... .............. Unknown for U.S.-- unknown increasing in the U.S.
Western North Atlantic (EEZ), but the rate
stock. of increase is
unknown.
Harbor porpoise............. 390 79,883--Gulf of Maine/ 0.48 unknown.
Bay of Fundy stock.
Atlantic white-sided dolphin 72 48,819--Western North 0.15 unknown.
Atlantic stock.
Minke whale................. 16 20,741--Canadian East 0.077 unknown.
Coast stock.
----------------------------------------------------------------------------------------------------------------
* Note: Any pinnipeds observed/taken by Level B harassment will likely be harbor seals rather than gray seal (as
gray seals do not frequent the waters of the project area as much and are found more in Canadian waters/haul
out).
Analysis and Determinations
Negligible Impact
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.'' A negligible impact finding is based on the
lack of likely adverse effects on annual rates of recruitment or
survival (i.e., population-level effects). An estimate of the number of
Level B harassment takes alone is not enough information on which to
base an impact determination. In addition to considering estimates of
the number of marine mammals that might be ``taken'' through behavioral
harassment, we consider other factors, such as the likely nature of any
responses (e.g., intensity, duration), the context of any responses
(e.g., critical reproductive time or location, migration), as well as
the number and nature of estimated Level A harassment takes, the number
of estimated mortalities, and effects on habitat.
Pile driving activities associated with this project have the
potential to disturb or displace marine mammals. Elevated noise levels
are expected to be generated as a result of these activities. However,
ME DOT will use noise attenuation devices (e.g., pile cushions, bubble
curtains) during impact pile driving to ensure that sound levels of 180
dB (rms) do not extend more than 10 m from the pile, which eliminates
the potential for injury (PTS) and temporary threshold shift. Serious
injury or mortality is not expected at all, and with mitigation, we
expect to avoid any potential for Level A harassment as a result of the
EBRP activities, and none are authorized by NMFS. The specified
activities may result in take, in the form of Level B harassment
(behavioral disturbance) only, from in-water noise from construction
activities.
Effects on individuals that are taken by Level B harassment, on the
basis reports in the literature as well as monitoring from other
similar activities, will likely be limited to reactions from these low
intensity, localized, and short-term noise exposures that may cause
brief startle reactions or short-term behavioral modifications by the
animals. These reactions and behavioral changes are expected to subside
quickly when the exposures cease. Moreover, marine mammals are expected
to avoid the area during in-water construction because animals
generally move away from active sound sources, thereby reducing
exposure and impacts. In addition, through mitigation measures
including soft start, marine mammals are expected to move away from a
sound source that is annoying prior to its becoming potentially
injurious and detection of marine mammals by observers will enable the
implementation of shutdowns to avoid injury. Repeated exposures of
individuals to levels of noise disturbance that may cause Level B
harassment are unlikely to result in hearing impairment or to
significantly disrupt foraging behavior.
[[Page 13593]]
In-water construction activities will occur in relatively shallow
coastal waters of Cobscook Bay. The project area is not considered
significant habitat for marine mammals and therefore no adverse effects
on marine mammal habitat are expected. Marine mammals approaching the
action area will likely be traveling or opportunistically foraging.
There are no rookeries or major haul-out sites nearby, foraging
hotspots, or other ocean bottom structure of significant biological
importance to marine mammals that may be present in the marine waters
in the vicinity of the project area. The closest significant pinniped
haul out is more than six nmi away, which is well outside the project
area's largest harassment zone. The project area is not a prime habitat
for marine mammals, nor is it considered an area frequented by marine
mammals. Therefore, behavioral disturbances that could result from
anthropogenic noise associated with breakwater replacement activities
are expected to affect only small numbers of marine mammals on an
infrequent basis. Although it is possible that some individual marine
mammals may be exposed to sounds from in-water construction activities
more than once, the duration of these multi-exposures is expected to be
low since animals will be constantly moving in and out of the area and
in-water construction activities will not occur continuously throughout
the day.
Harbor and gray seals, harbor porpoise, Atlantic white-sided
dolphins and minke whales as the potentially affected marine mammal
species under NMFS' jurisdiction in the action area, are not listed as
threatened or endangered under the ESA and are not considered strategic
under the MMPA. Because of the low level of impact, even repeated Level
B harassment of some small subset of the overall stocks is unlikely to
result in any significant realized decrease in fitness to those
individuals, and thus would not result in any adverse impact to the
stocks as a whole. Additionally, Level B harassment will be reduced to
the level of least practicable impact through use of mitigation
measures described herein and, if sound produced by project activities
is sufficiently disturbing, animals are likely to avoid the project
area while the activity is occurring.
In summary, this negligible impact analysis is founded on the
following factors: (1) The possibility of injury, serious injury, or
mortality may reasonably be considered discountable; (2) The
anticipated incidents of Level B harassment consist of, at worst,
temporary modifications in behavior; (3) There is no known foraging or
reproductive habitat in the project area and the project activities are
not expected to result in the alteration of habitat important to these
behaviors or substantially impact the behaviors themselves; (4) There
is no major haul out habitat within six nmi of the project area; (5)
The project area is not a prime habitat for marine mammals, nor will
the activity otherwise have adverse effects on marine mammal habitat;
and (6) Mitigation measures are expected to be effective in reducing
the effects of the specified activity to the level of least practicable
impact. In addition, these stocks are not listed under the ESA or
considered depleted under the MMPA. In combination, we believe that
these factors, as well as the available body of evidence from other
similar activities, demonstrate that the potential effects of the
specified activities will have only short-term effects on individuals.
The specified activities are not expected to have adverse effects on
annual rates of recruitment or survival and will therefore not result
in population-level impacts.
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, and taking into
consideration the implementation of the monitoring and mitigation
measures, we preliminarily find that the total marine mammal take from
the construction activities will have a negligible impact on the
affected marine mammal species or stocks.
Small Numbers
The amount of take NMFS is authorizing is considered small, less
than one percent relative to the estimated populations for harbor
porpoises, Atlantic white-sided dolphins, and minke whales and 2.11
percent for harbor seals. Based on the analysis contained herein of the
likely effects of the specified activity on marine mammals and their
habitat, and taking into consideration the implementation of the
mitigation and monitoring measures, NMFS finds that small numbers of
marine mammals will be taken relative to the populations of 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. Therefore, NMFS has determined that the total taking of
affected species or stocks would not have an unmitigable adverse impact
on the availability of such species or stocks for taking for
subsistence purposes.
Endangered Species Act (ESA)
No ESA-listed marine mammal species under NMFS' jurisdiction or
their designated critical habitat are expected to be affected by these
activities. Therefore, we have determined that a consultation under the
ESA is not required. The applicant consulted with the NMFS' GARFO for
federally listed fish species.
National Environmental Policy Act (NEPA)
NMFS prepared an EA and analyzed the potential impacts to marine
mammals that will result from the EBRP. A Finding of No Significant
Impact (FONSI) was signed January 2017. A copy of the EA and FONSI is
available upon request (see ADDRESSES).
Authorization
NMFS has issued an IHA to ME DOT for the potential harassment of
small numbers of marine mammals incidental to the EBRP in Eastport, ME,
provided the previously mentioned mitigation, monitoring and reporting.
Dated: March 8, 2017.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2017-04943 Filed 3-13-17; 8:45 am]
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