[Federal Register Volume 84, Number 113 (Wednesday, June 12, 2019)]
[Notices]
[Pages 27288-27300]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-12346]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN 0648-XG644-X
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to the O'Connell Bridge Lightering
Float Pile Replacement Project in Sitka, Alaska
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
Mammal Protection Act (MMPA) as amended, notification is hereby given
that NMFS has issued an incidental harassment authorization (IHA) to
the City and Borough of Sitka (CBS) to incidentally harass, by Level B
harassment only, marine mammals during the O'Connell Bridge Lightering
Float Pile Replacement Project in Sitka, Alaska.
DATES: This Authorization is effective from June 1, 2019 through May
31, 2020.
FOR FURTHER INFORMATION CONTACT: Rob Pauline, Office of Protected
Resources, NMFS, and (301) 427-8401. Electronic
[[Page 27289]]
copies of the application and supporting documents, as well as a list
of the references cited in this document, may be obtained online at:
https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act. In case of problems accessing these
documents, please call the contact listed above.
SUPPLEMENTARY INFORMATION:
Background
The MMPA prohibits the ``take'' of marine mammals, with certain
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to
allow, upon request, the incidental, but not intentional, taking of
small numbers of marine mammals by U.S. citizens who engage in a
specified activity (other than commercial fishing) within a specified
geographical region if certain findings are made and either regulations
are issued or, if the taking is limited to harassment, a notice of a
proposed incidental take authorization may be 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) and will not have an unmitigable adverse impact on the
availability of the species or stock(s) for taking for subsistence uses
(where relevant). Further, NMFS must prescribe the permissible methods
of taking and other means of effecting the least practicable adverse
impact on the affected species or stocks and their habitat, paying
particular attention to rookeries, mating grounds, and areas of similar
significance, and on the availability of such species or stocks for
taking for certain subsistence uses (referred to in shorthand as
mitigation); and requirements pertaining to the mitigation, monitoring
and reporting of such takings are set forth.
Summary of Request
On November 18, 2018, NMFS received a request from CBS for an IHA
to take marine mammals incidental to pile driving and removal
activities associated with the O'Connell Bridge Lightering Float Pile
Replacement Project in Sitka, Alaska. The application was deemed
adequate and complete on February 5, 2019. CBS's request is for take of
small numbers of humpback whale (Megaptera novaeangliae), minke whale
(Balaenoptera acutorostrata), killer whale (Orcinus orca), harbor
porpoise (Phocoena phocoena), harbor seal (Phoca vitulina), and Steller
sea lion (Eumetopias jubatus) by Level A and Level B harassment.
Neither CBS nor NMFS expects serious injury or mortality to result from
this activity and, therefore, an IHA is appropriate.
Description of Specified Activity
Overview
CBS is repairing the O'Connell Bridge Lightering Float (float)
located in Sitka Sound in Southeast Alaska. The applicant plans to
remove existing piles and replace them with piles that are more deeply
socketed so that the float can accommodate larger vessels including
yachts, fish processors, and research vessels. Existing piles are not
socketed deep enough to provide proper stability to safely support
these vessels. Additionally, the float was damaged during a storm in
June of 2017, and the existing piles are now leaning. This project will
replace the existing piles with new piles that are socketed deeper into
the ocean floor. Once the piles are replaced, the float will safely
accommodate these larger vessels. Vibratory pile removal, vibratory
pile driving, impact pile driving, and drilling will introduce sound
into nearby waters at levels that could result in behavioral harassment
of marine mammals.
A detailed description of the planned O'Connell Bridge project is
provided in the Federal Register notice for the proposed IHA (84 FR
7023; March 1, 2019). Pile removal and installation is expected to
occur for a total of approximately 13 hours over 3 days and is
scheduled to take place in June 2019. As a contingency, the IHA is
effective for a period of one year, from June 1, 2019 through May 31,
2020. Since that time, no changes have been made to the planned project
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 CBS was published in
the Federal Register on March 1, 2019 (84 FR 7023). That notice
described, in detail, CBS's activity, the marine mammal species that
may be affected by the activity, the anticipated effects on marine
mammals and their habitat, proposed amount and manner of take, and
proposed mitigation, monitoring and reporting measures. On March 18,
2019, NMFS received a comment letter from the Marine Mammal Commission
(Commission); the Commission's recommendations and our responses are
provided here, and the comments have been posted online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities. The Commission recommended
that NMFS issue the IHA, subject to inclusion of the proposed
mitigation, monitoring, and reporting measures.
Comment 1: The Commission recommended that NMFS refrain from
implementing its renewal process and instead use abbreviated Federal
Register notices, reference existing documents, and provide a 30-day
public comment period in order to streamline the incidental harassment
authorization process. The Commission further recommended that if NMFS
did not pursue a more general route, NMFS should provide the Commission
and the public with a legal analysis supporting its conclusion that the
process is consistent with the requirements under section 101(a)(5)(D)
of the MMPA.
Response 1: The notice of the proposed IHA expressly notifies the
public that under certain, limited conditions an applicant could seek a
renewal IHA for an additional year. The notice describes the conditions
under which such a renewal request could be considered and expressly
seeks public comment in the event such a renewal is sought. Additional
reference to this solicitation of public comment has recently been
added at the beginning of Federal Register notices that consider
renewals. NMFS appreciates the streamlining achieved by the use of
abbreviated Federal Register notices and intends to continue using them
for proposed IHAs that include minor changes from previously issued
IHAs, but which do not satisfy the renewal requirements. However, we
believe our method for issuing renewals meets statutory requirements
and maximizes efficiency. Importantly, such renewals would be limited
to where the activities are identical or nearly identical to those
analyzed in the proposed IHA, monitoring does not indicate impacts that
were not previously analyzed and authorized, and the mitigation and
monitoring requirements remain the same, all of which allow the public
to comment on the appropriateness and effects of a renewal at the same
time the public provides comments on the initial IHA.
Regarding the sufficiency of the public comment period, NMFS has
taken a number of steps to ensure the public has adequate notice, time,
and information to be able to comment effectively on renewal IHAs
within the limitations of processing IHA applications efficiently. The
Federal Register notice for the proposed initial IHA had previously
identified the
[[Page 27290]]
conditions under which a one-year renewal IHA might be appropriate.
This information is presented in the Request for Public Comments
section and thus encourages submission of comments on the potential of
a one-year renewal as well as the initial IHA during the 30-day comment
period. In addition, when we receive an application for a renewal IHA,
we will publish notice of the proposed renewal IHA in the Federal
Register and provide an additional 15 days for public comment, making a
total of 45 days of public comment. We will also directly contact all
commenters on the initial IHA by email, phone, or, if the commenter did
not provide email or phone information, by postal service to provide
them the opportunity to submit any additional comments on the proposed
renewal IHA.
NMFS has also modified the language for future IHAs to clarify that
all IHAs, including renewal IHAs, are valid for no more than one year
and that the agency would consider only one renewal for a project at
this time. In addition, notice of issuance or denial of a renewal IHA
would be published in the Federal Register, as are all IHAs. Last, NMFS
has published on our website a description of the renewal process
before any renewal is issued utilizing the new process.
Description of Marine Mammals in the Area of Specified Activities
Sections 3 and 4 of the application summarize available information
regarding status and trends, distribution and habitat preferences, and
behavior and life history, of the potentially affected species.
Additional information regarding population trends and threats may be
found in NMFS's Stock Assessment Reports (SAR; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and more general information about these species
(e.g., physical and behavioral descriptions) may be found on NMFS's
website (https://www.fisheries.noaa.gov/find-species).
Table 1 lists all species with expected potential for occurrence
near the project area and summarizes information related to the
population or stock, including regulatory status under the MMPA and ESA
and potential biological removal (PBR), where known. For taxonomy, we
follow Committee on Taxonomy (2018). PBR is 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 (as described in
NMFS's SARs). While no mortality is anticipated or authorized here, PBR
and annual serious injury and mortality from anthropogenic sources are
included here as gross indicators of the status of the species and
other threats.
Marine mammal abundance estimates presented in this document
represent the total number of individuals that make up a given stock or
the total number estimated within a particular study or survey area.
NMFS' stock abundance estimates for most species represent the total
estimate of individuals within the geographic area, if known, that
comprises that stock. For some species, this geographic area may extend
beyond U.S. waters. All managed stocks in this region are assessed in
NMFS' U.S. Alaska SARs (e.g., Muto et al. 2018). All values presented
in Table 1 are the most recent available at the time of publication and
are available in the 2017 SARs (Muto et al. 2018) and draft 2018 SARs
(available online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/draft-marine-mammal-stock-assessment-reports)
Table 1--Marine Mammals Potentially Present Within Sitka Sound During the Specified Activity
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ESA/ MMPA status; Stock abundance (CV,
Common name Scientific name Stock strategic (Y/N) Nmin, most recent PBR Annual M/
\1\ abundance survey) \2\ SI \3\
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Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
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Family Balaenidae:
Humpback whale.................. Megaptera novaeangliae. Central North Pacific.. -, -, Y 10,103 (0.3, 7,891, 83 26
2006).
Minke whale..................... Balaenoptera Alaska................. -, -, N N/A (See SAR), N/A, UND 0
acutorostrata. See SAR.
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Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
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Family Delphinidae:
Killer whale.................... Orcinus orca........... Alaska Resident........ -, -, N 2,347 (N/A, 2,347, 24 1
2012) \4\.
Northern Resident...... -, -, N 261 (N/A, 261, 2011) 1.96 0
\4\.
Gulf of Alaska, -, -, N 587 (N/A, 587, 2012) 5.87 1
Aleutian Islands, \4\.
Bering Sea Transient.
West Coast Transient... -, -, N 243 (N/A, 243, 2009) 2.4 0
\4\.
Family Phocoenidae (porpoises):
Harbor porpoise................. Phocoena phocoena...... Southeast Alaska....... -, -, Y 975 (0.12-0.14, 897, 8.9 34
2012) \5\.
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Order Carnivora--Superfamily Pinnipedia
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Family Otariidae (eared seals and
sea lions):
Steller sea lion................ Eumetopias jubatus..... Western U.S............ E, D, Y 54,267 (N/A, 54,267, 326 252
2017).
Eastern U.S............ -, D, Y 41,638 (N/A, 41,638, 2498 108
2015).
Family Phocidae (earless seals):
Harbor seal..................... Phoca vitulina Sitka/Chatham Strait... -, -, N 14,855 (N/A, 13,212, 555 77
richardii. 2011).
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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 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.
\2\ NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments assessments. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable (N/A).
\3\ These values, found in NMFS' SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g., commercial
fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV associated
with estimated mortality due to commercial fisheries is presented in some cases.
\4\ N is based on counts of individual animals identified from photo-identification catalogs.
[[Page 27291]]
\5\ In the SAR for harbor porpoise, NMFS identified population estimates and PBR for porpoises within inland southeast Alaska waters (these abundance
estimates have not been corrected for g(0); therefore, they are likely conservative).
A detailed description of the of the species likely to be affected
by the O'Connell Bridge project, 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 (84 FR 7023; March 1, 2019); since that time, we are not
aware of any changes in the status of these species and stocks;
therefore, detailed descriptions are not provided here. Please refer to
that Federal Register notice for these descriptions. More general
information about these species (e.g., physical and behavioral
descriptions) may be found on NMFS' website (https://www.fisheries.noaa.gov/find-species).
Potential Effects of Specified Activities on Marine Mammals and Their
Habitat
Underwater noise from impact and vibratory pile driving and down-
the-hole drilling activities associated with the planned O'Connell
Bridge project has the potential to result in harassment of marine
mammals in the vicinity of the action area. The Federal Register notice
for the proposed IHA (84 FR 7023; March 1, 2019) included a discussion
of the potential effects of such disturbances on marine mammals and
their habitat, therefore that information is not repeated in detail
here; please refer to the Federal Register notice (84 FR 7023; March 1,
2019) for that information.
Estimated Take
This section provides an estimate of the number of incidental takes
authorized through this IHA, which will inform both NMFS' consideration
of ``small numbers'' and the negligible impact determination.
Harassment is the only type of take expected to result from these
activities. 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).
Authorized takes would be by Level B harassment, in the form of
disruption of behavioral patterns for individual marine mammals
resulting from exposure to impact and vibratory hammers and down-the-
hole drilling. Limited take by Level A harassment, in the form of
permanent threshold shift (PTS) is also authorized for harbor seals.
Note that seals would have to remain in the Level A harassment zone for
a long enough period to incur auditory injury.
As described previously, no mortality is anticipated or authorized
for this activity. Below we describe how the take is estimated.
Generally speaking, we estimate take by considering: (1) Acoustic
thresholds above which NMFS believes the best available science
indicates marine mammals will be behaviorally harassed or incur some
degree of permanent hearing impairment; (2) the area or volume of water
that will be ensonified above these levels in a day; (3) the density or
occurrence of marine mammals within these ensonified areas; and, (4)
and the number of days of activities. We note that while these basic
factors can contribute to a basic calculation to provide an initial
prediction of takes, additional information that can qualitatively
inform take estimates is also sometimes available (e.g., previous
monitoring results or average group size). Below, we describe the
factors considered here in more detail and present the calculated take
estimate.
Acoustic Thresholds
Using the best available science, NMFS has developed acoustic
thresholds that identify the received level of underwater sound above
which exposed marine mammals would be reasonably expected to be
behaviorally harassed (equated to Level B harassment) or to incur PTS
of some degree (equated to Level A harassment).
Level B Harassment for non-explosive sources--Though significantly
driven by received level, the onset of behavioral disturbance from
anthropogenic noise exposure is also informed to varying degrees by
other factors related to the source (e.g., frequency, predictability,
duty cycle), the environment (e.g., bathymetry), and the receiving
animals (hearing, motivation, experience, demography, behavioral
context) and can be difficult to predict (Southall et al., 2007,
Ellison et al., 2012). Based on what the available science indicates
and the practical need to use a threshold based on a factor that is
both predictable and measurable for most activities, NMFS uses a
generalized acoustic threshold based on received level to estimate the
onset of behavioral harassment. NMFS predicts that marine mammals are
likely to be behaviorally harassed in a manner we consider Level B
harassment when exposed to underwater anthropogenic noise above
received levels of 120 dB re 1 [mu]Pa (rms) for continuous (e.g.,
vibratory pile-driving, drilling) and above 160 dB re 1 [mu]Pa (rms)
for non-explosive impulsive (e.g., seismic airguns) or intermittent
(e.g., scientific sonar) sources. CBS's planned activity includes the
use of continuous (vibratory pile driving/removal and drilling) and
impulsive (impact pile driving) sources, and therefore the 120 and 160
dB re 1 [mu]Pa (rms) thresholds are applicable.
Level A harassment for non-explosive sources--NMFS' Technical
Guidance for Assessing the Effects of Anthropogenic Sound on Marine
Mammal Hearing (Version 2.0) (NMFS 2018) identifies dual criteria to
assess auditory injury (Level A harassment) to five different marine
mammal groups (based on hearing sensitivity) as a result of exposure to
noise from two different types of sources (impulsive or non-impulsive).
CBS's planned activity includes the use of impulsive (impact pile
driving) and non-impulsive (vibratory pile driving/removal and
drilling) sources.
These thresholds are provided in the table below. The references,
analysis, and methodology used in the development of the thresholds are
described in NMFS 2018 Technical Guidance, which may be accessed at:
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.
[[Page 27292]]
Table 2--Thresholds Identifying the Onset of Permanent Threshold Shift
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PTS onset thresholds \*\ (received level)
Hearing group ------------------------------------------------------------------------
Impulsive Non-impulsive
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Low-Frequency (LF) Cetaceans........... L0-pk,flat: 219 dB; LE, LE,LF,24h: 199 dB.
LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans........... L0-pk,flat: 230 dB; LE, MF,24h: 198 dB.
LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans.......... L0-pk,flat: 202 dB; LE, HF,24h: 173 dB.
LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater)..... L0-pk.flat: 218 dB; LE,PW,24h: 201 dB.
LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater).... L0-pk,flat: 232 dB; LE,OW,24h: 219 dB.
LE,OW,24h: 203 dB.
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* Dual metric thresholds for impulsive sounds: Use whichever results in the largest isopleth for calculating PTS
onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level thresholds
associated with impulsive sounds, these thresholds are recommended for consideration.
Note: Peak sound pressure level (L0-pk) has a reference value of 1 [micro]Pa, and weighted cumulative sound
exposure level (LE,) has a reference value of 1[micro]Pa\2\s. In this table, thresholds are abbreviated to be
more reflective of International Organization for Standardization standards (ISO 2017). The subscript ``flat''
is being included to indicate peak sound pressure are flat weighted or unweighted within the generalized
hearing range of marine mammals (i.e., 7 Hz to 160 kHz). The subscript associated with cumulative sound
exposure level thresholds indicates the designated marine mammal auditory weighting function (LF, MF, and HF
cetaceans, and PW and OW pinnipeds) and that the recommended accumulation period is 24 hours. The weighted
cumulative sound exposure level thresholds could be exceeded in a multitude of ways (i.e., varying exposure
levels and durations, duty cycle). When possible, it is valuable for action proponents to indicate the
conditions under which these thresholds will be exceeded.
Ensonified Area
Here, we describe operational and environmental parameters of the
activity that will feed into identifying the area ensonified above the
acoustic thresholds, which include source levels and transmission loss
coefficient.
The sound field in the project area is the existing background
noise plus additional construction noise from the planned project.
Marine mammals are expected to be affected via sound generated by the
primary components of the project (i.e., impact pile driving, vibratory
pile driving and removal and down-the-hole drilling). The maximum
(underwater) ensonified area is truncated by land masses and largely
confined to marine waters within Eastern Channel of Sitka Sound,
extending approximately 7.7 kilometers through Crescent Bay, Middle
Channel, and into Eastern Channel and encompassing approximately 7.26
square kilometers (see Figure 5 in the application).
The distances to the Level A and Level B harassment thresholds were
calculated based on source levels from the Naval Base Kitsap at Bangor
EHW-1 Pile Replacement Project, in Bangor, Washington (NAVFAC 2012) and
the Kodiak Ferry Terminal Project in Kodiak, Alaska (Denes et. al.
2016) for a given activity and pile type (e.g., vibratory removal/
installation, drilling, and impact pile driving of 24-inch diameter
steel piles). The vibratory source level is proxy from 24-inch steel
piles driven at the Naval Base Kitsap in Bangor, Washington (NAVFAC
2012) and from acoustic modeling of nearshore marine pile driving at
Navy installations in Puget Sound (United States Navy 2015). The
socketing source level is proxy from mean measured sources levels from
drilling of 24-inch diameter piles to construct the Kodiak Ferry
Terminal (Denes et al. 2016). Sound pressure level root-mean-square
(SPL rms) values were used to calculate distance to Level A and B
harassment isopleths for impact pile driving. The source levels of
168.2 SEL (for Level A harassment) and 181.3 SPL (for Level B
harassment) are the mean measured levels from the Kodiak Ferry Terminal
project (Denes et al. 2016).
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 (R 1/R 2),
where
TL = transmission loss in dB
B = transmission loss coefficient; for practical spreading equals 15
R 1 = the distance of the modeled SPL from the driven
pile, and
R 2 = the distance from the driven pile of the initial
measurement
A practical spreading value of 15 is often used under conditions,
such as at the lightering dock location, 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. Practical spreading loss is
assumed here.
When the NMFS Technical Guidance (2016) was published, in
recognition of the fact that ensonified area/volume could be more
technically challenging to predict because of the duration component in
the new thresholds, we developed a User Spreadsheet that includes tools
to help predict a simple isopleth that can be used in conjunction with
marine mammal density or occurrence to help predict takes. We note that
because of some of the assumptions included in the methods used for
these tools, we anticipate that isopleths produced are typically going
to be overestimates of some degree, which may result in some degree of
overestimate of Level A harassment take. However, these tools offer the
best way to predict appropriate isopleths when more sophisticated 3D
modeling methods are not available, and NMFS continues to develop ways
to quantitatively refine these tools, and will qualitatively address
the output where appropriate. For stationary sources such as pile
driving and drilling, NMFS User Spreadsheet predicts the closest
distance at which, if a marine mammal remained at that distance the
whole duration of the activity, it would not incur PTS. Inputs used in
the User Spreadsheet, and the resulting isopleths are reported in
Tables 3 and 4. Note that the distance of source level measurements for
drilling were incorrect in the Federal Register notice of proposed IHA
as they were sourced at 1 meter when they should have been sourced at
10 m. Additionally, we have revised the SL for drilling/socketing.
Originally, we used an average SL of 167.7 dB RMS from (Denes et al.
2016). However, we recently determined it more appropriate to use the
median value (166.2 dB RMS) rather than the mean. We also determined
that we should be using Tab A.1 of the User Spreadsheet instead of Tab
A for down-the-hole drilling. The drilling associated with Tab A is
more
[[Page 27293]]
applicable to off-shore drilling while Tab A.1 better represents down-
the-hole drilling.
Updated values are provided in Table 4 which presents the Level B
harassment isopleth associated with impact pile driving (160 dB) and
vibratory pile driving/removal and drilling (120 dB). The Level B
harassment isopleth for drilling socketing has also been updated to
reflect the use of a SL of 166.2 dB RMS.
Table 3--User Spreadsheet Input Parameters Used for Calculating Harassment Isopleths
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Vibratory driving Drilling/socketing Impact driving
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(A.1) Vibratory driving-- (A.1) Vibratory driving-- (E.1) Impact pile
Spreadsheet tab used stationary source: Non- stationary source: Non- driving (stationary
impulsive, continuous impulsive, continuous source: Impulsive,
intermittent
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Source Level (dB).................. 161 RMS SPL.............. 166.2 RMS SPL............ 168.2 SEL.
Weighting Factor Adjustment (kHz).. 2.5...................... 2........................ 2.
(a) Number of piles in 24-hr....... 12....................... n/a...................... 6.
(b) Number of strikes/pile......... n/a...................... n/a...................... 5.
(c) Duration of sound (hours) n/a...................... 6........................ n/a.
within 24-h period.
(d) Duration of drive single pile 5........................ n/a...................... n/a.
(minutes).
Propagation (xLogR)................ 15....................... 15....................... 15.
Distance of source level 10....................... 10....................... 10.
measurement (meters).
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* n/a: not applicable.
Table 4--Calculated Distances to Level A Harassment and Level B Harassment Isopleths During Pile Installation and Removal and Drilling
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Distance (m) to level A and level B thresholds
-----------------------------------------------------------------------
Level A
Activity Source level at 10 meters (dB) ------------------------------------------------------------
Low- Mid- High- Level B
frequency frequency frequency Phocid Otariid
cetaceans cetaceans cetaceans
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Vibratory Pile Driving/Removal:
16-inch steel removal and installation (12 161 SPL......................... 6.8 0.6 10.1 4.2 0.3 5,412
piles) (~1 hour on 1 day).
Drilling/Socketing Pile Installation:
16-inch steel installation (6 piles) (6 166.2 SPL....................... 50.1 4.4 74.1 30.5 2.1 * 12,022
hours per day on 2 days).
Impact Pile Driving:
16-inch steel installation (6 piles) (~3 168.2 SEL/181.3 SPL............. 9.9 0.4 11.8 5.3 0.4 263
minutes per day on 1 day).
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* Ensonified area truncated by land masses with a maximum extent of 7.7 km.
Marine Mammal Occurrence and Take Calculation and Estimation
In this section we provide the information about the presence,
density, or group dynamics of marine mammals that will inform the take
calculations and how this information is brought together to produce a
quantitative take estimate.
Density information is not available for marine mammals in the
project area. Potential exposures for marine mammals were estimated
from several sources. Between the months of September through May from
1994 to 2002, weekly surveys were conducted from Sitka's Whale Park,
located at the easternmost end of Eastern Channel as shown in Figure 5
in the application. More recent data (from 2002 to present) were
collected from small vessels or Allen Marine 100-foot catamarans during
school field trips in and around Eastern Channel. Additionally, marine
mammal observational data was collected in the Sitka Channel as part of
the Gary Paxton Industrial Park (GPIP) Multipurpose Dock Project
(Turnagain 2017). Monitors were present during twenty-two days of in
water work as part of this project. This included ten days between
October 9th and 20th, 2017 for wooden pile removal, where only one
monitor was present each day and twelve days between October 22nd and
November 9th, where two observers were monitoring during new pile
installation. Additionally, data was collected in January and October/
November of 2017 in the Sitka Channel when Petro Marine Services
removed and replaced a fuel float in the Sitka Channel and recorded
marine mammal observations (Windward 2017). Finally, marine mammal
observation reports covering the months of June through September, 2018
were also reviewed (Turnagain 2018).
Level B Harassment Calculations
The estimation of takes by Level B harassment uses the following
calculation:
Level B harassment estimate = N (number of animals in the
ensonified area) * Number of days of noise generating activities.
Humpback Whale
Humpback whales are the most commonly observed baleen whale in
Southeast Alaska, particularly during spring and summer months.
Humpback whales frequent the action area and could be encountered
during any given day of pile driving/removal activities. In
[[Page 27294]]
the project vicinity, humpback whales typically occur in groups of 1 to
2 animals, with an estimated maximum group size of 4 animals. Most
humpback whales observed in the area were solitary. When more than one
whale was observed, available survey data reports a typical group size
of 2-4 whales (Straley et al. 2018). During work on GPIP Dock, groups
of 5 and 10 individuals were seen a few times, but most of the time,
single whales were observed (Turnagain 2017). CBS conservatively
estimates that a group of 5 humpback whales may occur within the Level
B harassment zone every day of the 3-day construction window during
active pile driving (5 animals in a group x 1 group each day x 3 days =
15 animals). Therefore, NMFS has authorized 15 takes by Level B
harassment of humpback whales. Based on Wade et al. (2016), the
probability is that 93.9 percent of the humpback whales taken would be
from the Hawaii DPS (not listed under ESA) and 6.1 percent of the
humpback whales taken would be from the ESA-listed threatened Mexico
DPS.
Minke Whale
After informal consultation with the Commission, NMFS opted to
conservatively authorize three minke whale takes by Level B harassment
based on monitoring data from Biorka Island which reported observations
of these whales on numerous days (Turnagain 2018). NMFS had not
originally proposed take of this species in the Federal Register
proposed IHA.
Killer Whale
Killer whales pass through the action area and could be encountered
during any given day of pile removal and installation. In the project
vicinity, typical killer whale pod sizes vary between 4-8 individuals,
with an estimated maximum group size of 8 animals (Straley et al.
2018). A pod of three killer whales were observed during monitoring for
the Petro Marine Dock, and a pod of eight whales were observed on one
day near Biorka Island (Windward 2017; Turnagain 2018). CBS estimates
that a group of 8 killer whales may occur within the Level B harassment
zone every day of during active pile driving (8 animals in a group x 1
group each day x 3 days = 24 animals). Therefore, NMFS has authorized
24 killer whales takes by Level B harassment.
Harbor Porpoise
Harbor porpoises are seen infrequently in the action area, but they
could be encountered during any given day of pile replacement
activities. The mean group size of harbor porpoise in Southeast Alaska
was estimated to be between two to three individuals (Dahlheim et al.
2009). In the project vicinity, harbor porpoises typically occur in
groups of 1-5 animals, with an estimated maximum group size of eight
animals (Straley et al. 2018). No harbor porpoises were seen during the
Petro Marine Dock construction monitoring in January 2017 or during
monitoring for the GPIP dock between October and November of 2017
(Windward 2017 and Turnagain 2017). CBS conservatively estimates that a
group of 5 harbor porpoise may occur within the Level B harassment zone
once each day during the 3-day construction window during active pile
driving (5 animals in a group x 1 group each day x 3 days = 15
animals). Therefore, NMFS has authorized 15 Level B harassment takes of
harbor porpoises.
Harbor Seal
Harbor seals are common in the action area and are expected to be
encountered during pile replacement activities. In the action area
harbor seals typically occur in groups of 1-3 animals. Observations
near Sitka Channel recorded only individual seals, and observations for
GPIP dock observed mostly individuals, however, a few groups with up to
3 seals were observed. Near Biorka Island, recent sightings ranged from
1 individual to a group of 9 (June and September 2018). At Biorka
Island, up to 23 harbor seals were observed during a single day
(Turnagain 2018). Therefore, after informal consultation with the
Commission, NMFS has conservatively authorized 69 takes (23 per day
over 3 days) of harbor seal which represents an increase over the 18
takes by Level B harassment proposed for authorization under the
Federal Register proposed IHA. NMFS has also authorized the take of 30
seals by Level A harassment. CBS will employ a 10 meter shutdown zone
for harbor seals. This will allow CBS to avoid repeated shutdowns due
to the presence of seals in the immediate vicinity of the project site.
The established Level A harassment zone for phocids will extend to 35
meters. Any harbor seal observed between 10 and 35 meters will be
recorded as a take by Level A harassment. NMFS has authorized 30 harbor
seal takes by Level A harassment by assuming 10 animals per day will
enter into the injury zone. With total harbor seal exposures estimated
at 69, NMFS has authorized the remaining 39 exposures as takes by Level
B harassment.
Steller Sea Lion
Steller sea lions are common in the action area and are expected to
be encountered during pile removal and driving. In the project vicinity
Steller sea lions typically occur in groups of 1-8 animals near the
project area (Turnagain 2017 and Windward 2017), with an estimated
maximum group size of 100 animals (Straley et al. 2018). Commission
informally noted that Steller sea lions can occur in the action area
every day during construction and that 11 sea lions were observed on
multiple days at GPIP (Turnagain 2017) Therefore, NMFS has authorized
33 takes (11 animals per day over 3 days) of sea lion by Level B
harassment. This represents an increase over the 24 takes that were
described in the Federal Register notice of proposed IHA.
CBS intends to avoid Level A harassment take of marine mammals,
other than harbor seals, by shutting down pile removal or installation
activities at the approach of any animal into their identified Level A
harassment (PTS onset) zone.
Table 6--Estimated Take by Level A and Level B Harassment, by Species, Stock and Percent of Stock
----------------------------------------------------------------------------------------------------------------
Percent of
Species Stock (population) Level A Level B stock
----------------------------------------------------------------------------------------------------------------
Humpback Whale........................ Central North Pacific .............. 15 0.15
(10,103).
Minke Whale........................... Alaska (N.A.)........... .............. 3 N.A.
Killer Whale.......................... Alaska Resident (2,347). .............. \1\ 24 1.02
Northern Resident (261). .............. .............. 9.20
West Coast Transient .............. .............. 9.88
(243).
Gulf of Coast, Aleutian. .............. .............. ..............
Islands, Bering Sea .............. .............. 4.09
Transient (587).
Harbor Porpoise....................... Southeast Alaska (975).. .............. 15 1.54
[[Page 27295]]
Harbor Seal........................... Sitka/Chatham Strait 30 39 0.46
(14,855).
Stellar Sea Lion...................... Western DPS (54,267).... .............. \1\ 33 0.06
Eastern DPS (41,638).... 0.08
----------------------------------------------------------------------------------------------------------------
\1\ Assumes all takes come from each individual stock.
Mitigation
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 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 (latter not applicable for this action). 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 and their habitat (50 CFR
216.104(a)(11)).
In evaluating how mitigation may or may not be appropriate to
ensure the least practicable adverse impact on species or stocks and
their habitat, as well as subsistence uses where applicable, we
carefully consider two primary factors:
(1) 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, and their habitat.
This considers the nature of the potential adverse impact being
mitigated (likelihood, scope, range). It further considers the
likelihood that the measure will be effective if implemented
(probability of accomplishing the mitigating result if implemented as
planned) the likelihood of effective implementation (probability
implemented as planned); and
(2) the practicability of the measures for applicant
implementation, which may consider such things as cost, impact on
operations, and, in the case of a military readiness activity,
personnel safety, practicality of implementation, and impact on the
effectiveness of the military readiness activity.
In addition to the measures described later in this section, CBS
will employ the following standard mitigation measures:
Conduct briefings between construction supervisors and
crews and the marine mammal monitoring team prior to the start of all
pile driving activity, and when new personnel join the work, to explain
responsibilities, communication procedures, marine mammal monitoring
protocol, and operational procedures;
For in-water heavy machinery work other than pile driving
(e.g., standard barges, etc.), if a marine mammal comes within 10 m,
operations shall cease and vessels shall reduce speed to the minimum
level required to maintain steerage and safe working conditions. This
type of work could include the following activities: (1) Movement of
the barge to the pile location; or (2) positioning of the pile on the
substrate via a crane (i.e., stabbing the pile);
Work may only occur during daylight hours, when visual
monitoring of marine mammals can be conducted;
For those marine mammals for which take by Level B
harassment has not been requested, in-water pile installation/removal
and drilling will shut down immediately if such species are observed
within or on a path towards the monitoring zone (i.e., Level B
harassment zone); and
If take reaches the authorized limit for an authorized
species, pile driving activities will be stopped as these species
approach the Level B harassment zone to avoid additional take.
The following measures will apply to CBS's mitigation requirements:
Establishment of Shutdown Zone--For all pile driving/removal and
drilling activities, CBS will establish a shutdown zone to avoid take
by Level A harassment. The purpose of a shutdown zone is generally 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). The shutdown zone will be 10 m in most cases. The
shutdown zone for high-frequency cetaceans will be 15 m for vibratory
pile driving/removal and impact pile driving. During drilling/socketing
installation the shutdown zone for high-frequency cetaceans and low-
frequency cetaceans has been increased from the values presented in the
Federal Register notice of proposed IHA to 75 m and 55 m respectively
(Table 7). These changes were made to account for the revised SL and
sourcing data that was previously described for drilling/socketing
activities (Table 7). These defined shutdown zones will be used to
prevent incidental Level A harassment exposures of species authorized
for take except for harbor seals. The Level A harassment zone for
harbor seals extends to 35 m with a 10 m shutdown zone during all pile
driving and drilling activities. The placement of Protected Species
Observers (PSOs) during all pile driving and drilling activities
(described in detail in the Monitoring and Reporting Section) will
ensure shutdown zones are visible and adequately monitored.
Table 7--Shut Down Zone for Each Project Activity
----------------------------------------------------------------------------------------------------------------
High-
Low- frequency Mid- frequency frequency
Noise source cetaceans cetaceans cetaceans Phocid (harbor Otariid (sea
(humpback (killer whale) (harbor seal) lion)
whale) porpoise)
----------------------------------------------------------------------------------------------------------------
Vibratory Pile Driving/Removal:
[[Page 27296]]
16-inch steel removal and 10 10 15 10 10
installation (12 piles) (~1
hour on 1 day).............
Drilling/Socketing Pile
Installation:
16-inch steel installation 55 10 75 10 10
(6 piles) (6 hours per day
on 2 days).................
Impact Pile Driving:
16-inch steel installation 10 10 15 10 10
(6 piles) (~3 minutes on 1
day).......................
----------------------------------------------------------------------------------------------------------------
Establishment of Monitoring Zones for Level B Harassment--CBS will
establish monitoring zones to correlate with Level B harassment
disturbance zones or zones of influence which are areas where SPLs are
equal to or exceed the 160 dB rms threshold for impact driving and the
120 dB rms threshold during vibratory driving and drilling. Monitoring
zones provide utility for observing by establishing monitoring
protocols for areas adjacent to the shutdown zones. Monitoring zones
enable observers to be aware of and communicate the presence of marine
mammals in the project area outside the shutdown zone and thus prepare
for a potential cease of activity should the animal enter the shutdown
zone. The monitoring zones are described in Table 8. The monitoring
zone for drilling activities extends 7,700 m from the noise source,
corresponding to the maximum distance before landfall. It is likely
that PSOs will not be able to effectively observe the entire monitoring
zone. Therefore, Level B harassment exposures will be recorded and
extrapolated based upon the number of observed takes and the percentage
of the Level B harassment zone that was not visible.
Table 8--Level B Harassment Monitoring Zones
------------------------------------------------------------------------
Monitoring
zones for take
Pile driving noise source by Level B
harassment
(meter)
------------------------------------------------------------------------
Vibratory Pile Driving:
16-inch steel removal and installation (12 piles) 5,500
(~1 hour on 1 day).................................
Socketing Pile Installation:
16-inch steel installation (6 piles) (6 hours per 7,700
day on 2 days).....................................
Impact Pile Driving:
16-inch steel installation (6 piles) (~3 minutes per 265
day on 1 day)......................................
------------------------------------------------------------------------
Use of Pile Caps/Cushions--Pile driving softening material (i.e.,
pile caps/cushions) will be used to minimize noise during vibratory and
impact pile driving. Much of the noise generated during pile
installation comes from contact between the pile being driven and the
steel template used to hold the pile in place. The contractor will use
high-density polyethylene (HDPE) or ultra-high-molecular-weight
polyethylene (UHMW) softening material on all templates to eliminate
steel on steel noise generation.
Direct Pull--To minimize construction noise levels as much as
possible, the contractor will first attempt to direct pull old piles;
if those efforts prove to be ineffective, they will proceed with a
vibratory hammer.
Reduced Energy--To reduce noise production, the vibratory hammer
will be operated at a reduced energy setting (30 to 50 percent of its
rated energy).
Soft Start--The use of soft-start procedures are believed to
provide additional protection to marine mammals by providing warning
and/or giving marine mammals a chance to leave the area prior to the
hammer operating at full capacity. For impact pile driving, contractors
will be required to provide an initial set of strikes from the hammer
at reduced energy, with each strike followed by a 30-second waiting
period. This procedure will be conducted a total of three times before
impact pile driving begins. Soft start will be implemented at the start
of each day's impact pile driving (if more than one day) and at any
time following cessation of impact pile driving for a period of thirty
minutes or longer. Soft start is not required during vibratory pile
driving and removal activities.
Pre-Activity Monitoring--Prior to the start of daily in-water
construction activity, or whenever a break in pile driving/removal or
drilling of 30 minutes or longer occurs, PSOs will observe the shutdown
and monitoring zones for a period of 30 minutes. The shutdown zone will
be cleared when a marine mammal has not been observed within the zone
for the 30-minute period. If a marine mammal is observed within the
shutdown zone, a soft-start cannot proceed until the animal has left
the zone or has not been observed for 15 minutes. If the Level B
harassment zone has been observed for 30 minutes and non-permitted
species are not present within the zone, soft start procedures can
commence and work can continue even if visibility becomes impaired
within the Level B harassment monitoring zone. When a marine mammal
permitted for Level B take is present in the Level B harassment zone,
activities may begin and Level B take will be recorded. As stated
above, if the entire Level B harassment zone is not
[[Page 27297]]
visible at the start of construction, piling driving or drilling
activities can begin. If work ceases for more than 30 minutes, the pre-
activity monitoring of both the Level B harassment and shutdown zone
will commence.
Based on our evaluation of the applicant's proposed measures, as
well as other measures considered by NMFS, NMFS has determined that the
required mitigation measures provide the means effecting the least
practicable impact on the affected species or stocks and their habitat,
paying particular attention to rookeries, mating grounds, and areas of
similar significance.
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
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
action area. Effective reporting is critical both to compliance as well
as ensuring that the most value is obtained from the required
monitoring.
Monitoring and reporting requirements prescribed by NMFS should
contribute to improved understanding of one or more of the following:
Occurrence of marine mammal species or stocks in the area
in which take is anticipated (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 marine mammal responses (behavioral or
physiological) to acoustic stressors (acute, chronic, or cumulative),
other stressors, or cumulative impacts from multiple stressors;
How anticipated responses to stressors impact either: (1)
Long-term fitness and survival of individual marine mammals; or (2)
populations, species, or stocks;
Effects on marine mammal habitat (e.g., marine mammal prey
species, acoustic habitat, or other important physical components of
marine mammal habitat); and
Mitigation and monitoring effectiveness.
Monitoring shall be conducted by NMFS-approved PSOs. Trained
observers shall be placed from the best vantage point(s) practicable to
monitor for marine mammals and implement shutdown or delay procedures
when applicable through communication with the equipment operator.
Observer training must be provided prior to project start, and shall
include instruction on species identification (sufficient to
distinguish the species in the project area), description and
categorization of observed behaviors and interpretation of behaviors
that may be construed as being reactions to the specified activity,
proper completion of data forms, and other basic components of
biological monitoring, including tracking of observed animals or groups
of animals such that repeat sound exposures may be attributed to
individuals (to the extent possible).
Monitoring will be conducted 30 minutes before, during, and 30
minutes after pile driving/removal and drilling activities. In
addition, observers shall record all incidents of marine mammal
occurrence, regardless of distance from activity, and shall document
any behavioral reactions in concert with distance from piles being
driven or removed. Pile driving/removal and drilling activities include
the time to install or remove a single pile or series of piles, as long
as the time elapsed between uses of the pile driving equipment is no
more than 30 minutes.
PSOs will scan the waters using binoculars, and/or spotting scopes,
and will use a handheld GPS or range-finder device to verify the
distance to each sighting from the project site. All PSOs will be
trained in marine mammal identification and behaviors and are required
to have no other project-related tasks while conducting monitoring. In
addition, monitoring will be conducted by qualified observers, who will
be placed at the best vantage point(s) practicable to monitor for
marine mammals and implement shutdown/delay procedures when applicable
by calling for the shutdown to the hammer operator. CBS will adhere to
the following observer qualifications:
1. Independent observers (i.e., not construction personnel) are
required.
2. At least one observer must have prior experience working as an
observer.
3. Other observers may substitute education (degree in biological
science or related field) or training for experience.
4. NMFS will require submission and approval of observer CVs.
CBS must ensure that observers have the following additional
qualifications:
1. Ability to conduct field observations and collect data according
to assigned protocols;
2. Experience or training in the field identification of marine
mammals, including the identification of behaviors;
3. Sufficient training, orientation, or experience with the
construction operation to provide for personal safety during
observations;
4. 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 in-water construction activities were
conducted; dates, times, and reason for implementation of mitigation
(or why mitigation was not implemented when required); and marine
mammal behavior; and
5. 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.
Two land-based PSOs will be used to monitor the area during all
pile driving and removal activities. One PSO will monitor from the
O'Connell Bridge which features a high vantage point with unobstructed
views of, and close proximity to, the project site. A second monitor
will be stationed east of the construction site, likely off Islander
Drive. PSOs will work in shifts lasting no longer than 4 hours with at
least a 1-hour break between shifts, and will not perform duties as a
PSO for more than 12 hours in a 24-hr period to reduce PSO fatigue.
A draft marine mammal monitoring report will be submitted to NMFS
within 90 days after the completion of pile driving and removal and
drilling activities. It will include an overall description of work
completed, a narrative regarding marine mammal sightings, and
associated PSO data sheets. Specifically, the report must include:
Dates and times (begin and end) of all marine mammal
monitoring.
Construction activities occurring during each daily
observation period, including how many and what type of piles were
driven or removed and by what method (i.e., impact or vibratory).
Weather parameters and water conditions during each
monitoring
[[Page 27298]]
period (e.g., wind speed, percent cover, visibility, sea state).
The number of marine mammals observed, by species,
relative to the pile location and if pile driving or removal was
occurring at time of sighting.
Age and sex class, if possible, of all marine mammals
observed.
PSO locations during marine mammal monitoring.
Distances and bearings of each marine mammal observed to
the pile being driven or removed for each sighting (if pile driving or
removal was occurring at time of sighting).
Description of any marine mammal behavior patterns during
observation, including direction of travel.
Number of individuals of each species (differentiated by
month as appropriate) detected within the monitoring zone, and
estimates of number of marine mammals taken, by species (a correction
factor may be applied to total take numbers, as appropriate).
Detailed information about any implementation of any
mitigation triggered (e.g., shutdowns and delays), a description of
specific actions that ensued, and resulting behavior of the animal, if
any.
Description of attempts to distinguish between the number
of individual animals taken and the number of incidences of take, such
as ability to track groups or individuals.
If no comments are received from NMFS within 30 days, the draft
final report will constitute the final report. If comments are
received, a final report addressing NMFS comments must be submitted
within 30 days after receipt of comments.
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, serious injury or mortality, CBS will
immediately cease the specified activities and report the incident to
the Chief of the Permits and Conservation Division, Office of Protected
Resources, NMFS, and the Alaska Regional Stranding Coordinator. The
report will include the following information:
Description of the incident;
Environmental conditions (e.g., Beaufort sea state,
visibility);
Description of all marine mammal observations in the 24
hours 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 CBS to
determine what is necessary to minimize the likelihood of further
prohibited take and ensure MMPA compliance. CBS will not be able to
resume their activities until notified by NMFS via letter, email, or
telephone.
In the event that CBS 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 (e.g., in less than a
moderate state of decomposition as described in the next paragraph),
CBS will immediately report the incident to the Chief of the Permits
and Conservation Division, Office of Protected Resources, NMFS, and the
Alaska Regional Stranding Coordinator. The report will include the same
information identified in the paragraph above. Activities will be able
to continue while NMFS reviews the circumstances of the incident. NMFS
will work with CBS to determine whether modifications in the activities
are appropriate.
In the event that CBS 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), CBS will report the incident to
the Chief of the Permits and Conservation Division, Office of Protected
Resources, NMFS, and the Alaska Regional Stranding Coordinator, within
24 hours of the discovery. CBS will provide photographs, video footage
(if available), or other documentation of the stranded animal sighting
to NMFS and the Marine Mammal Stranding Network.
Negligible Impact 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 (50 CFR 216.103). 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 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 harassment, NMFS considers 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 effects on habitat, and the likely effectiveness
of the mitigation. We also assess the number, intensity, and context of
estimated takes by evaluating this information relative to population
status. Consistent with the 1989 preamble for NMFS's implementing
regulations (54 FR 40338; September 29, 1989), the impacts from other
past and ongoing anthropogenic activities are incorporated into this
analysis via their impacts on the environmental baseline (e.g., as
reflected in the regulatory status of the species, population size and
growth rate where known, ongoing sources of human-caused mortality, or
ambient noise levels).
Pile driving, pile removal and drilling activities as outlined
previously, have the potential to disturb or displace marine mammals.
Specifically, the specified activities may result in take in the form
of Level B harassment from underwater sounds generated from vibratory
pile removal, vibratory pile driving, impact pile driving, and drilling
over 3 days. Potential takes could occur if individuals of these
species are present in the ensonified zone when these activities are
underway. One day of work will be dedicated to removing 6 old and
installing 6 new piles which will emit low levels of noise into the
aquatic environment if removed via direct pull or vibratory hammer and
installed via vibratory hammer as planned. Vibratory removal and
installation will take approximately one hour. Drilling will occur for
only 6 hours per day over 2 days. Impact driving will be used to proof
socketed piles and take place for a total of 3 minutes on a single day.
Effects on individuals that are taken by Level A harassment will
likely include minor PTS to a limited number of animals, consisting of
hearing loss of no more than a few dB. Level B harassment, on the basis
of reports in the literature as well as monitoring from other similar
activities, will likely be limited to reactions such as increased
swimming speeds, increased surfacing time, or decreased foraging (if
such activity were occurring) (e.g., Thorson and Reyff 2006; HDR, Inc.
2012; Lerma 2014; ABR 2016). Most likely, individuals will simply move
away from the sound source and be temporarily displaced from the areas
of pile driving and drilling, although even this reaction has been
observed primarily only in association with impact pile driving. The
pile driving activities analyzed here are similar to, or less impactful
than, numerous other
[[Page 27299]]
construction activities conducted in southeast Alaska, which have taken
place with no known long-term adverse consequences from behavioral
harassment. Level A and Level B harassment will be reduced to the level
of least practicable adverse impact through use of mitigation measures
described herein and, if sound produced by project activities is
sufficiently disturbing, animals are likely to simply avoid the area
while the activity is occurring.
The project also is not expected to have significant adverse
effects on affected marine mammals' habitat. Project activities will
not modify existing marine mammal habitat for a significant amount of
time. The activities may cause some fish to leave the area of
disturbance, thus temporarily impacting marine mammals' foraging
opportunities in a limited portion of the foraging range. However,
because of the short duration of the activities and the relatively
small area of the habitat that may be affected, and the decreased
potential of prey species to be in the project area during the
construction work window, the impacts to marine mammal habitat are not
expected to cause significant or long-term negative consequences.
In summary and as described above, the following factors primarily
support our determination that the impacts resulting from this activity
are not expected to adversely affect the species or stock through
effects on annual rates of recruitment or survival:
No mortality is anticipated or authorized;
Limited take by Level A harassment, consisting of small
degree of hearing loss;
Level B harassment may consist of, at worst, temporary
modifications in behavior (e.g., temporary avoidance of habitat or
changes in behavior);
The specified activity is temporary and of short duration;
The ensonified area is very small relative to the overall
habitat ranges of all species and does not include habitat areas of
special significance (BIAs or ESA-designated critical habitat); and
The presumed efficacy of the mitigation measures in
reducing the effects of the specified activity to the level of least
practicable adverse impact.
In addition, although affected humpback whales and Steller sea
lions may be from a DPS that is listed under the ESA, it is unlikely
that minor noise effects in a small, localized area of habitat will
have any effect on the stocks' ability to recover. 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 minor effects on
individuals. The specified activities are not expected to impact 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, NMFS finds that the total marine mammal take from the planned
activity will have a negligible impact on all affected marine mammal
species or stocks.
Small Numbers
As noted above, only small numbers of incidental take may be
authorized under sections 101(a)(5)(A) and (D) of the MMPA for
specified activities other than military readiness activities. The MMPA
does not define small numbers and so, in practice, where estimated
numbers are available, NMFS compares the number of individuals taken to
the most appropriate estimation of abundance of the relevant species or
stock in our determination of whether an authorization is limited to
small numbers of marine mammals. Additionally, other qualitative
factors may be considered in the analysis, such as the temporal or
spatial scale of the activities.
Table 6 presents the number of animals that could be exposed to
received noise levels that may result in Level B take for the planned
work at O'Connell Bridge. Our analysis shows that less than 10 percent
of the best available population estimate of each affected stock could
be taken. Furthermore, these percentages conservatively assume that all
takes of killer whale and Steller sea lion will be accrued to a single
stock, when multiple stocks are known to occur in the project area.
There was one stock, minke whale, where the lack of an accepted stock
abundance value did not allow for the calculation an expected
percentage of the population that would be affected. The most relevant
estimate of partial stock abundance is 1,233 minke whales for a portion
of the Gulf of Alaska (Zerbini et al. 2006). Given 3 authorized takes
by Level B harassment for the stock, comparison to the best estimate of
stock abundance shows less than 1 percent of the stock is expected to
be impacted. Therefore, the numbers of animals authorized to be taken
for all species will be considered small relative to the relevant
stocks or populations even if each estimated taking occurred to a new
individual--an extremely unlikely scenario. For pinnipeds, especially
harbor seals and Steller sea lions, occurring in the vicinity of the
project site, there could be some overlap in individuals present day-
to-day, and these takes are likely to occur only within some small
portion of the overall regional stock.
Based on the analysis contained herein of the planned activity
(including the required mitigation and monitoring measures) and the
anticipated take of marine mammals, NMFS finds that small numbers of
marine mammals will be taken relative to the population size of the
affected species or stocks.
Unmitigable Adverse Impact Analysis and Determination
In order to issue an IHA, NMFS must find that the specified
activity will not have an ``unmitigable adverse impact'' on the
subsistence uses of the affected marine mammal species or stocks by
Alaskan Natives. NMFS has defined ``unmitigable adverse impact'' in 50
CFR 216.103 as an impact resulting from the specified activity: (1)
That is likely to reduce the availability of the species to a level
insufficient for a harvest to meet subsistence needs by: (i) Causing
the marine mammals to abandon or avoid hunting areas; (ii) Directly
displacing subsistence users; or (iii) Placing physical barriers
between the marine mammals and the subsistence hunters; and (2) That
cannot be sufficiently mitigated by other measures to increase the
availability of marine mammals to allow subsistence needs to be met.
The peak hunting season in southeast Alaska occurs during the month
of November and again over the March to April time frame (Wolfe et al.
2013). The planned project is in an area where subsistence hunting for
harbor seals or sea lions could occur (Wolfe et al. 2013), but the area
near the project location is not preferred for hunting.
During September 2018, CBS contacted the Alaska Harbor Seal
Commission, the Alaska Sea Otter and Steller Sea Lion Commission, and
the Sitka Tribe of Alaska. These organizations expressed no concerns
about the impact of the action on subsistence marine mammals or their
harvest by hunters near the project area. The Sitka Tribe did request
that no pile driving occur between March 15 and May 31 to protect
herring, as has been the case for past permitting in Sitka Sound. In
response to this request, CBS will not commence in-water construction
operations prior to June 1, 2019 or between March 15, 2020 and May 31,
2020.
[[Page 27300]]
Based on the description of the specified activity, the measures
described to minimize adverse effects on the availability of marine
mammals for subsistence purposes, and the mitigation and monitoring
measures, NMFS has determined that there will not be an unmitigable
adverse impact on subsistence uses from CBS's planned activities.
National Environmental Policy Act
To comply with the National Environmental Policy Act of 1969 (NEPA;
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A,
NMFS must review our proposed action (i.e., the issuance of an
incidental harassment authorization) with respect to potential impacts
on the human environment.
This action is consistent with categories of activities identified
in Categorical Exclusion B4 (incidental harassment authorizations with
no anticipated serious injury or mortality) of the Companion Manual for
NOAA Administrative Order 216-6A, which do not individually or
cumulatively have the potential for significant impacts on the quality
of the human environment and for which we have not identified any
extraordinary circumstances that would preclude this categorical
exclusion. Accordingly, NMFS has determined that the issuance of the
IHA qualifies to be categorically excluded from further NEPA review.
Endangered Species Act (ESA)
Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 16
U.S.C. 1531 et seq.) requires that each Federal agency insure that any
action it authorizes, funds, or carries out is not likely to jeopardize
the continued existence of any endangered or threatened species or
result in the destruction or adverse modification of designated
critical habitat. To ensure ESA compliance for the issuance of IHAs,
NMFS consults internally, in this case with NMFS' Alaska Regional
Office, whenever we propose to authorize take for endangered or
threatened species.
NMFS is authorizing take of two DPSs (i.e., western DPS of Steller
sea lions and Mexico DPS of humpback whales), which are listed under
the ESA. The NMFS Alaska Regional Office issued a Biological Opinion in
May 2019, under Section 7 of the ESA, on the issuance of an IHA to CBS
under section 101(a)(5)(D) of the MMPA by the NMFS Office of Protected
Resources. The Biological Opinion concluded that the proposed action is
not likely to jeopardize the continued existence of western DPS Steller
sea lions or Mexico DPS of humpback whales, and is not likely to
destroy or adversely modify western DPS Steller sea lion critical
habitat.
Authorization
NMFS has issued an IHA to CBS for the incidental take of marine
mammals due to in-water construction work associated with the O'Connell
Bridge Lightering Float Pile Replacement project in Sitka, Alaska from
June 1, 2019 through May 31, 2020, provided the previously mentioned
mitigation, monitoring, and reporting requirements are incorporated.
Dated: May 23, 2019.
Shannon Bettridge,
Acting Deputy Director, Office of Protected Resources, National Marine
Fisheries Service.
[FR Doc. 2019-12346 Filed 6-11-19; 8:45 am]
BILLING CODE 3510-22-P