[Federal Register Volume 84, Number 195 (Tuesday, October 8, 2019)]
[Notices]
[Pages 53689-53699]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-21905]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN 0648-XG908
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to the King Pile Markers Project on
the Columbia River
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 U.S. Army Corps of Engineers, Portland District (Corps) to
incidentally harass, by Level A and Level B harassment only, marine
mammals during the King Pile Markers Project on the Columbia River in
Washington and Oregon.
DATES: This Authorization is effective from October 1, 2020 through
September 30, 2021.
FOR FURTHER INFORMATION CONTACT: Robert Pauline, Office of Protected
Resources, NMFS, (301) 427-8401. Electronic 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.
The definitions of all applicable MMPA statutory terms cited above
are included in the relevant sections below.
Summary of Request
On February 11, 2019, NMFS received a request from the Corps for an
IHA to take marine mammals incidental to pile driving associated with
the replacement of king pile markers at numerous dike locations in the
lower Columbia River system. The king pile markers are located in
Oregon and Washington between river miles (RM) 41 and 137. The
application was deemed adequate and complete on August 2, 2019. The
Corps' request is for take of small numbers of harbor seal (Phoca
vitulina), Steller sea lion (Eumetopias jubatus),
[[Page 53690]]
and California sea lion (Zalophus californianus) that may occur in the
vicinity of the project by Level A and Level B harassment. Neither the
Corps nor NMFS expects serious injury or mortality to result from this
activity and, therefore, an IHA is appropriate.
Description of Planned Activity
Overview
The Corps is replacing up to 68 king pile markers at 68 pile dike
sites along the lower Columbia River between river miles (RM) 41 and
137. There are a total of 256 pile dikes, in the existing dike system.
The king piles that require replacement are not functioning as
intended. They were designed to aid navigation by helping mariners
avoid pile dikes during high water. Many existing king piles are either
missing completely, damaged, or degraded to a point where they no
longer provide a visual identifier. This lack of visibility poses a
safety concern to both recreational and commercial boaters on the
river. Replacement of the king piles will improve visibility of pile
dikes and improve safety for Columbia River traffic. Impact and
vibratory pile installation would introduce underwater sounds at levels
that may result in take, by Level B harassment, of marine mammals in
the lower Columbia River. Pile installation is expected to occur for up
to 61 days and take place in October and November of 2020. As a
contingency, the IHA is effective for a period of one year, from
October 1, 2020 through September 30, 2021.
A detailed description of the planned King Pile Project is provided
in the Federal Register notice for the proposed IHA (84 FR 44866;
August 27, 2019). 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
We published a notice of receipt of the Corps' application and
proposed IHA in the Federal Register on August 27, 2019 (84 FR 44866).
That notice described, in detail, the Corps' 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
(Commission).
Comment: The Commission recommended that NMFS authorize 52 Level B
harassment takes and 1 Level A harassment take of harbor seals and 27
Level B harassment takes of Steller sea lions for each of the 68 piles
to be driven. The Commission also recommended that take should be
calculated based on the number of piles driven instead of the number of
working days.
Response: For harbor seals, NMFS has accepted the Commission's
recommendation to calculate take based on the total number of piles
instead of the total number of driving days as up to nine piles could
be driven in single day. The Commission noted that there are a number
of harbor seal haulouts located along the section of the Columbia River
where king piles will be installed (Jeffries et al. 2000). However,
this data is 20 years old, and biologists with the Corps indicated
there were not aware of large harbor seal haul-outs in close proximity
to any of the king pile locations. NMFS has increased the take of
harbor seals from three per day to 10 per pile based on local anecdotal
evidence included in the Port of Kalama IHA application for the Kalama
Manufacturing and Marine Export Facility (81 FR 89436; December 12,
2016). Since the anecdotal evidence pertains to a single fixed
location, without an associated temporal component. NMFS calculated
take based on the number of piles, instead of the number of days. It is
important to note that driving times are relatively short at each king
pile location and will require no more than 1 hour of impact and 30
minutes of vibratory driving. NMFS is also authorizing Level A take of
10 harbor seals as it is possible during impact pile driving that some
small number of individuals could enter the permanent threshold shift
(PTS) zone and stay for a sufficient duration to be taken before being
detected by observers. Of the haulouts cited by Jeffries et al. (2000)
only 5 were located in the project area and these were described as low
use. A total of 10 king pile installation locations are located within
five miles of these haulouts.
In the proposed rule, NMFS based Level B take of Steller sea lions
on observations at one of three tailtraces at Bonneville Dam. NMFS
multiplied the number (56) by 3 to account for all the tailtraces for
each driving day in the proposed IHA. NMFS understands that many of
these observations are likely repeated sightings of the same animal and
acknowledges that this take estimate is likely overestimated. A number
of these sea lions were ``branded'' and could be individually
identified. Some of these identified animals were observed at the dam
over multiple days. NMFS acknowledges that the number of sea lions
swimming up and down the Columbia River, passing king pile markers
along the way, is far less than the number observed at the dam.
Therefore, NMFS will assume that 56 (the maximum number seen at where
observations were conducted at the tailtrace, instead of multiplying by
3) is the total number of Steller sea lions could be taken per day
resulting in 3,416 takes by Level B harassment. The take estimate for
California sea lions remains unchanged at 9 per day for a total of 549
takes by Level B harassment.
Comment: If NMFS chooses to authorize 56 Level B harassment takes
of Steller sea lion per day, the Commission recommends that, at a
minimum, NMFS authorize the same number of Level B harassment takes of
harbor seals as Steller sea lions and include 1 Level A harassment take
per pile of harbor seals.
Response: NMFS explained the reasoning behind the revised estimated
take numbers for harbor seals and Steller sea lions in the previous
response. NMFS does agree that that authorizing limited take of harbor
seals by Level A harassment is prudent and has included this as part of
the final authorization. The PTS isopleth is 56.9 meters (m) for harbor
seals during impact pile driving so it is conceivable that a harbor
seal could enter the Level A harassment zone before being detected
resulting in multiple shutdowns which could delay the project, however,
the small size of the zone and the likelihood of some degree of
aversion make it unlikely that this would happen often.
Comment: The Commission recommended that NMFS obtain more recent
pinniped haul-out count data from Washington Department of Fish and
Wildlife and the Oregon Department of Fish and Wildlife before
processing any additional authorizations for activities occurring in
the Columbia River.
Response: When NMFS receives another application for an IHA at a
location on the Columbia River these agencies will be contacted.
Comment: The Commission recommended that NMFS conduct a more
thorough review of the applications and Federal Register notices to
ensure accuracy, completeness, and consistency and to ensure that they
are based on best available science, prior to submitting them to the
Federal Register for public comment.
Response: NMFS thanks the Commission for its recommendation. NMFS
makes every effort to read the notices thoroughly prior to publication
and will continue this effort to publish
[[Page 53691]]
the best possible product for public comment using the best available
science
Comment: The Commission recommended that NMFS conduct a more
thorough review of final incidental harassment authorizations and
letters of authorization to ensure accuracy and completeness and
consistency with the information stipulated in the Federal Register
notice for final issuance.
Response: NMFS thanks the Commission for its concerns regarding the
IHA process and will make a concerted effort to ensure that language in
the final IHA is in agreement with text in the Federal Register notice
for final issuance.
Comment: The Commission recommended that NMFS refrain from using
the proposed renewal process for the Corps' authorization. The renewal
process should be used sparingly and selectively, by limiting its use
only to those proposed incidental harassment authorizations that are
expected to have the lowest levels of impacts on marine mammals and
that require the least complex analyses. If NMFS elects to use the
renewal process frequently or for authorizations that require a more
complex review or for which much new information has been generated the
Commission recommended that NMFS provide the Commission and other
reviewers the full 30-day comment period as set forth in section
101(a)(5)(D)(iii) of the MMPA.
Response: We appreciate the Commission's input and direct the
reader to our recent response to the identical comment, which can be
found at 84 FR 52464 (October 2, 2019), pg. 52466.
Comment: The Commission recommended that, for all relevant
incidental take authorizations, NMFS refrain from using a source level
reduction factor for sound attenuation device implementation during
impact pile driving, including the 24-in steel piles proposed for use
by USACE, until such time that it consults with Caltrans regarding the
appropriate source level reduction factor to use to minimize far-field
effects on marine mammals.
Response: We direct the reader to our recent response to the nearly
identical comment, which can be found at 84 FR 45983 (September 3,
2019), pg. 45985. NMFS will evaluate the appropriateness of using a
certain source level reduction factor for sound attenuation device
implementation during impact pile driving for all relevant incidental
take authorizations when more data become available. Caltrans and other
entities that have pertinent data may be contacted as necessary.
Changes From the Proposed IHA to Final IHA
The project has been delayed by one year due to contracting issues.
Therefore, construction activities will not begin until October 1,
2020. Therefore, NMFS has revised the effective dates of the IHA from
October 1, 2020 through September 30, 2021 to reflect this change.
As described in the Federal Register notice for the proposed IHA
(84 FR 44866; August 27, 2019), NMFS did not propose take by Level A
harassment. The permanent threshold shift (PTS) isopleth is 56.9 m for
harbor seal for an hour of impact pile driving. As such, it is possible
that during the course of the activities some small number of harbor
seals could enter the Level A harassment zone and stay for a sufficient
duration to be taken before the Corps detects them and is able to
shutdown. Therefore, in consideration of the recommendation from the
Commission, NMFS is authorizing 10 instances of take of harbor seal by
Level A harassment. NMFS has also revised Level B harassment takes for
harbor seals based on the number of piles installed instead of the
number of pile driving days. These changes are described in the
``Estimated Take'' section.
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 (SARs; 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 marine mammal species with expected potential for
occurrence in the lower Columbia River 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 (2016). 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's stock abundance estimates for most species represent the total
estimate of individuals within the geographic area, if known, that
comprise that stock. For some species, this geographic area may extend
beyond U.S. waters. All managed stocks in this region are assessed in
NMFS's 2018 U.S. Pacific Marine Mammal SARs (Carretta et al., 2019).
All values presented in Table 1 are the most recent available at the
time of publication and are available in the 2018 SARs (Carretta et
al., 2019).
Table 1--Marine Mammal Species Likely To Be in Lower Columbia River Near King Pile Marker Sites
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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 Carnivora--Superfamily Pinnipedia
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Family Otariidae (eared seals and
sea lions):
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California sea lion............. Zalophus californianus. U.S. Stock............. -, -, N 257,606 (N/A, 233,515, 14,011 >320
2014).
[[Page 53692]]
Steller sea lion................ Eumetopias jubatus..... Eastern U.S............ -, -, N 41,638 (See SAR, 2,498 108
41,638, 2015).
Family Phocidae (earless seals):
Harbor seal..................... Phoca vitulina Oregon and Washington -, -, N UNK (UNK, UNK, 1999).. UND 10.6
richardii. Coast.
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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: www.nmfs.noaa.gov/pr/sars/. CV is coefficient of variation; Nmin is the minimum estimate of
stock abundance. In some cases, CV is not applicable.
\3\ These values, found in NMFS's 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.
All species that could potentially occur in the planned survey
areas are included in Table 1. All three species (with three managed
stocks) described below co-occur temporally and spatially co-occur with
the planned activity to the degree that take is reasonably likely to
occur, and we have authorized it.
A detailed description of the of the species likely to be affected
by the Corps' project, including brief introductions to the species and
relevant stocks as well as available information regarding population
trends and threats, were provided in the Federal Register notice for
the proposed IHA (84 FR 44866; August 27, 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. Please also refer
to NMFS' website (https://www.fisheries.noaa.gov/find-species) for
generalized species accounts.
Potential Effects of Specified Activities on Marine Mammals and Their
Habitat
Acoustic effects on marine mammals during the specified activity
can occur from vibratory and impact pile driving. The effects of
underwater noise from the Corps' planned activities have the potential
to result in Level A and Level B harassment of marine mammals in the
vicinity of the action area. The effects of pile driving on marine
mammals are dependent on several factors, including the size, type, and
depth of the animal; the depth, intensity, and duration of the pile
driving sound; the depth of the water column; the substrate of the
habitat; the standoff distance between the pile and the animal; and the
sound propagation properties of the environment. It is likely that the
pile driving could result in temporary, short term changes in an
animal's typical behavioral patterns and/or avoidance of the affected
area as well as minor PTS in a limited number of harbor seal. The
Federal Register notice for the proposed IHA (84 FR 44866; August 27,
2019) included a discussion of the effects of anthropogenic noise on
marine mammals, therefore that information is not repeated here.
Anticipated Effects on Marine Mammal Habitat
The main impact issue associated with the planned activity would be
temporarily elevated sound levels and the associated direct effects on
marine mammals. The most likely impact to marine mammal habitat occurs
from pile driving effects on likely marine mammal prey (i.e., fish)
near where the piles are installed. Impacts to the immediate substrate
during installation and removal of piles are anticipated, but these
would be limited to minor, temporary suspension of sediments, which
could impact water quality and visibility for a short amount of time,
but which would not be expected to have any effects on individual
marine mammals. Impacts to substrate are therefore not discussed
further. These potential effects are discussed in detail in the Federal
Register notice for the proposed IHA (84 FR 44866; August 27, 2019).
Estimated Take
This section provides an estimate of the number of incidental takes
authorized through this IHA, which informs 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).
Take of marine mammals incidental to the Corps' pile driving
activities could occur as a result of Level A and B harassment. 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 take estimate.
Acoustic Thresholds
Using the best available science, NMFS has developed acoustic
thresholds that identify the received level of underwater sound above
which
[[Page 53693]]
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.
The Corps' planned activity includes the use of continuous
(vibratory pile driving) and impulsive (impact pile driving) sources,
and therefore the 120 and 160 dB re 1 [mu]Pa (rms) 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) (Technical Guidance, 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). The Corp's planned activity includes the
use of impulsive (impact pile driving) and non-impulsive (vibratory
pile driving) source.
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.
Table 2--Thresholds Identifying the Onset of PTS
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PTS onset acoustic thresholds *
(received level)
Hearing group ---------------------------------------
Impulsive Non-impulsive
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Low-Frequency (LF) Cetaceans.... Cell 1: Lpk,flat: Cell 2: LE,LF,24h:
219 dB; 199 dB.
LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans.... Cell 3: Lpk,flat: Cell 4: LE,MF,24h:
230 dB; 198 dB.
LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans... Cell 5: Lpk,flat: Cell 6: LE,HF,24h:
202 dB; 173 dB.
LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) Cell 7: Lpk,flat: Cell 8: LE,PW,24h:
(Underwater). 218 dB; 201 dB.
LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) Cell 9: Lpk,flat: Cell 10:
(Underwater). 232 dB; LE,OW,24h: 219
LE,OW,24h: 203 dB. dB.
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* Dual metric acoustic 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
should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [micro]Pa,
and cumulative sound exposure level (LE) has a reference value of
1[micro]Pa\2\s. In this Table, thresholds are abbreviated to reflect
American National Standards Institute standards (ANSI 2013). However,
peak sound pressure is defined by ANSI as incorporating frequency
weighting, which is not the intent for this Technical Guidance. Hence,
the subscript ``flat'' is being included to indicate peak sound
pressure should be flat weighted or unweighted within the generalized
hearing range. 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
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 acoustic 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.
Sound Propagation
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:
B = transmission loss coefficient (assumed to be 15)
R1 = the distance of the modeled sound pressure Level 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)). As is
common practice in coastal waters, here we assume practical spreading
loss (4.5 dB reduction in sound level for each doubling of distance).
Practical spreading is a compromise that is often used under conditions
where water depth increases as the receiver moves away from the
shoreline, resulting in an expected propagation environment that would
lie between spherical and cylindrical spreading loss conditions.
Sound Source Levels
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. Pile driving may be done
with
[[Page 53694]]
either vibratory or impact hammer, with vibratory driving being the
preferred method. Due to anticipated enrockment surrounding existing
piles, however, use of impact hammers may be required.
Estimated in-water sound levels anticipated from vibratory
installation and impact hammer installation of steel pipe piles are
summarized in Table 3. Sound pressure levels for impact driving of 24-
in steel piles were taken from Caltrans (2015). The source levels (SLs)
in the table below include a 7 dB reduction for impact driving due to
attenuation associated with the use of bubble curtains. Vibratory
driving source levels for 24-in steel piles came from the United States
Navy (2015). Due to the short operating window (61 days), and concerns
about possible delays due to bad weather, the Corps does not propose to
use bubble curtains during vibratory driving. This should expedite pile
installation at king pile locations where use of vibratory hammers is
employed.
Table 3--Estimated Underwater Source Levels Associated With Vibratory Pile Driving and Impact Hammer Pile
Driving
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Pile type SPL (single strike)
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24-Inch Steel Pipe Piles w/ 200 dBPEAK................ 187 dBRMS................. 171 dBSEL.
impact hammer (attenuated) \1\.
24-Inch Steel Pipe Piles w/ Not Available............. 161 dBRMS................. Not Available.
vibratory (unattenuated) \2\.
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\1\ From Caltrans (2015) Acoustic data from CalTrans 2015 Table I.2-1. Summary of Near-Source (10-Meter)
Unattenuated Sound Pressure Levels for In-Water Pile Driving Using an Impact Hammer: 0.61-meter (24-inch)
steel pipe pile in water ~15 meters deep, w/7dB reduction for use of attenuation (as per NMFS 2019 pers.
Comm).
\2\ From United States Navy. 2015. Proxy source sound levels and potential bubble curtain attenuation for
acoustic modeling of nearshore marine pile driving at Navy installations in Puget Sound. Prepared by Michael
Slater, Naval Surface Warfare Center, Carderock Division, and Sharon Rainsberry, Naval Facilities Engineering
Command Northwest. Revised January 2015. Table 2-2.
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, NMFS User Spreadsheet predicts the distance at which, if a
marine mammal remained at that distance the whole duration of the
activity, it would incur PTS. Inputs used in the User Spreadsheet, and
the resulting Level A harassment isopleths are reported below in Tables
4 and 5 respectively. Note that while up to 9 piles could be installed
in a single day, they would be driven at different locations and the
ensonified areas associated with each location would not overlap. For
the purpose of calculating PTS isopleths using the User Spreadsheet, it
is assumed that a single pile would be driven per day at a single
location (i.e., the zones for each pile are calculated independently)
since there will be no overlap of disturbance zones from adjacent king
pile installation sites. The Level B harassment isopleths were
calculated using the practical spreading loss model. Underwater noise
will fall below the behavioral effects threshold of 160 dB for impact
driving and 120 dB rms for vibratory driving at the distances shown in
Table 5.
Table 4--NMFS Technical Guidance (2018) User Spreadsheet Input To Calculate PTS Isopleths
----------------------------------------------------------------------------------------------------------------
Inputs 24-in Steel impact installation 24-in Steel vibratory installation
----------------------------------------------------------------------------------------------------------------
Spreadsheet Tab Used.......... (E.1) Impact Pile Driving.............. (A.1) Vibratory Pile Driving
Source Level (Single Strike/ 171 dB SEL/200 dB Peak................. 161 dB RMS
shot SEL).
Weighting Factor Adjustment 2...................................... 2.5
(kHz).
Number of strikes per pile.... 550....................................
Number of piles per day....... 1...................................... 1
Duration to install single 60..................................... 30
pile (minutes).
Propagation (xLogR)........... 15..................................... 15
Distance of source level 10..................................... 10
measurement (meters) +.
----------------------------------------------------------------------------------------------------------------
Table 5--Level A and Level B Harassment Isopleths
----------------------------------------------------------------------------------------------------------------
Level A harassment PTS isopleth Level B harassment
(meters) isopleth (meters)
Noise generation type --------------------------------------------------------------
Phocid pinniped Otariid pinniped All groups
----------------------------------------------------------------------------------------------------------------
24'' Steel Pipe Impact attenuated................ 56.9 4.1 631
24'' Steel Pipe Vibratory unattenuated........... 2.6 0.2 5,412
----------------------------------------------------------------------------------------------------------------
[[Page 53695]]
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. Pinnipeds are typically concentrated at haul out sites
(e.g., the MCR South jetty) and feeding areas where there are
concentrations of salmon (e.g., Bonneville Dam). Individual animals
that occur near king pile locations are likely to be in transit between
these two prominent sites. Pinnipeds that travel to Bonneville Dam
consistently forage in all three of the dam's tailraces. A tailrace is
the flume, or water channel leading away from the dam. Pinniped
presence at the dam during the spring months has been recorded since
2002 and during fall/winter months starting in 2011 to assess the
impact of predation on adult salmonids and other fish (Tidwell et al.
2019).
Estimated take in the proposed IHA was calculated using the maximum
daily number of individuals observed at Bonneville dam (Tidwell et al.
2019), multiplied by the total number of work days (61). The maximum
daily number of animals observed at the dam between August 15 and
December 31 was used for both California sea lions (3 in 2015 and 2017)
and Steller sea lions (56 in 2016). No harbor seals were observed
during the fall/winter sampling period. However, only one of the three
tailraces was monitored during the fall/winter months and only when sea
lion abundance was >=20 animals. Therefore, NMFS multiplied the number
of observed California and Steller sea lions by three to account for
potential animals at all of the tailraces. Since there were no harbor
seals observed during the fall/winter period, NMFS used the maximum
daily observation from the spring observation period (3 in 2006) during
which all three tailraces were monitored.
For the final IHA, NMFS revised take numbers of Steller sea lions
and harbor seals. For Steller sea lions NMFS reduced take by utilizing
the maximum of observations (56) at only one tailrace instead of
multiplying by 3 as was done in the proposed IHA because many of these
observations at the dam are likely repeated sightings of the same
animal, some of whom are known to remain at the dam for extended
periods. NMFS feels this reduced take estimate is more appropriate
given that the initial estimate in the proposed IHA was overly
conservative. Therefore, NMFS will assume that 56 is the total number
of Steller sea lions could be taken per day resulting in 3,416 takes by
Level B harassment. Take of California sea lions remains unchanged at 9
takes per day.
Harbor seal takes were increased to 10 per pile based on anecdotal
evidence reported by the Port of Kalama in their IHA application for
the. Kalama Manufacturing and Marine Export Facility (81 FR 89436;
December 12, 2016). NMFS elected to calculate seal takes based on the
number of animals taken per pile instead of per day. This was done
since the anecdotal data represents a single location without any
temporal component on which a daily take rate could be derived. NMFS
authorized take of 10 harbor seals by Level A harassment since it is
possible during impact pile driving that a harbor seal could enter the
Level A harassment zone before being detected by observers.
Table 6 depicts the stocks NMFS proposes to authorize for take, the
numbers authorized, and the percentage of the stock taken.
Table 6--Level B Harassment Take Estimates for the King Pile Marker Project
----------------------------------------------------------------------------------------------------------------
Stock Percentage of
Species Level A take Level B take abundance stock taken
----------------------------------------------------------------------------------------------------------------
California Sea Lion......................... ............... 549 296,750 0.2
Stellar Sea Lion............................ ............... 3,416 41,638 8.2
Harbor Seal................................. 10 610 * 24,732 2.5
----------------------------------------------------------------------------------------------------------------
* There is no current estimate of abundance available for this stock since most recent abundance estimate is >8
years old. Abundance value provided represents best available information from 1999.
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, the
Corps must 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, tug boats), if a marine mammal comes within 10
m, operations shall cease and vessels shall reduce speed to
[[Page 53696]]
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 any marine mammal species for which take by Level B
harassment has not been requested or authorized, in-water pile
installation will shut down immediately when the animals are sighted;
If take by Level B harassment reaches the authorized limit
for an authorized species, pile installation will be stopped as these
species approach the Level B harassment zone to avoid additional take
of them.
Establishment of Shutdown and Level A Harassment Zones--For all
pile driving activities, the Corps shall establish a shutdown zone. The
purpose of a shutdown zone is generally to define an area within which
shutdown of activity would occur upon sighting of a marine mammal (or
in anticipation of an animal entering the defined area). Shutdown zones
will vary based on the type of driving activity and by marine mammal
hearing group. Shutdown zones during impact and vibratory driving will
be 10 m for all species. Planned shutdown zones are larger than the
calculated Level A harassment isopleths shown in Table 5 for Steller
sea lions and California sea lions. The Level A harassment zone is
larger for phocids than for other authorized species. Seals could
appear unexpectedly in this zone before being observed by protected
species observers (PSOs). Therefore, the area between 10 m and 60 m is
established as a Level A harassment zone for harbor seal and must be
monitored as such by PSOs. The placement of PSOs during all pile
driving activities (described in detail in the Monitoring and Reporting
Section) will ensure that the entirety of all shutdown zones are
visible during pile installation.
Establishment of Monitoring Zones for Level B Harassment--The Corps
will establish monitoring zones, based on the Level B harassment
isopleths 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. 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. In the unlikely event that a cetacean
enters the Level B harassment zones work will stop immediately until
the animal either departs the zone or is undetected for 15 minutes.
Distances to the Level B harassment zones are depicted in Table 5. In
addition, the Corps will establish minimum allowable work distances
between adjacent work platforms, based on monitoring zone isopleths, to
ensure that there is no overlap of behavioral harassment zones.
Sound Attenuation--Bubble curtains will be used during any impact
pile driving of piles located in water greater than 2 ft. in depth. The
bubble curtain will be operated in a manner consistent with the
following performance standards:
a. The bubble curtain will distribute air bubbles around 100
percent of the piling perimeter for the full depth of the water column;
b. The lowest bubble ring will be in contact with the mudline for
the full circumference of the ring, and the weights attached to the
bottom ring shall ensure 100 percent mudline contact. No parts of the
ring or other objects shall prevent full mudline contact; and
c. Air flow to the bubblers must be balanced around the
circumference of the pile.
Soft Start--The use of a soft-start procedure 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 percent energy, each strike followed by no less than a 30-
second waiting period. This procedure will be conducted a total of
three times before impact pile driving begins. Soft start is not
required during vibratory pile driving activities. A soft start must be
implemented at the start of each day's impact pile driving and at any
time following cessation of impact pile driving for a period of thirty
minutes or longer. If a marine mammal is present within the shutdown
zone, soft start will be delayed until the animal is observed leaving
the shutdown zone. Soft start will begin only after the PSO has
determined, through sighting, that the animal has moved outside the
shutdown zone or 15 minutes have passed without being seen in the zone.
If a marine mammal is present in the Level B harassment zone, soft
start may begin and a Level B take will be recorded for authorized
species. Soft start up may occur whether animals enter the Level B zone
from the shutdown zone or from outside the monitoring area.
Pre-Activity Monitoring--Prior to the start of daily in-water
construction activity, or whenever a break in pile driving 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 that 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 marine mammals 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 zone. When
a marine mammal permitted for take by Level B harassment is present in
the Level B harassment zone, pile driving activities may begin and take
by Level B will be recorded. 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 required measures, NMFS
has determined that the 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:
[[Page 53697]]
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.
Visual Monitoring
Monitoring would be conducted 30 minutes before, during, and 30
minutes after pile driving 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. Pile driving activities
include the time to install 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.
There will be at least one PSO employed at all king pile
installation locations during all pile driving activities. PSO will not
perform duties for more than 12 hours in a 24-hour period. The PSO
would be positioned close to pile driving activities at the best
practical vantage point.
As part of monitoring, PSOs would scan the waters using binoculars,
and/or spotting scopes, and would use a handheld GPS or range-finder
device to verify the distance to each sighting from the project site.
All PSOs would be trained in marine mammal identification and behaviors
and are required to have no other project-related tasks while
conducting monitoring. In addition, PSOs will monitor for marine
mammals and implement shutdown/delay procedures when applicable by
calling for the shutdown to the hammer operator. Qualified observers
are trained and/or experienced professionals, with the following
minimum qualifications:
Visual acuity in both eyes (correction is permissible)
sufficient for discernment of moving targets at the water's surface
with ability to estimate target size and distance; use of binoculars
may be necessary to correctly identify the target;
Independent observers (i.e., not construction personnel);
Observers must have their CVs/resumes submitted to and
approved by NMFS;
Advanced education in biological science or related field
(i.e., undergraduate degree or higher). Observers may substitute
education or training for experience;
Experience and ability to conduct field observations and
collect data according to assigned protocols (this may include academic
experience);
At least one observer must have prior experience working
as an observer;
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 in-water construction
activities were conducted; dates and times when in-water construction
activities were suspended to avoid potential incidental injury from
construction sound of marine mammals observed within a defined shutdown
zone; 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.
Due to the large size of the Level B harassment zones at each pile,
it is impracticable for the PSO to consistently view the entire
harassment area. Therefore, takes by Level B harassment 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.
Distances to the Level B harassment zones are depicted in Table 5.
Reporting
A draft marine mammal monitoring report must be submitted to NMFS
within 90 days after the completion of pile driving activities. This
reports will include an overall description of work completed, a
narrative regarding marine mammal sightings, and associated PSO data
sheets. Specifically, the reports must include:
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;
An estimate of total take based on proportion of the
monitoring zone that was observed;
Other human activity in the area; and
Marine mammal PSO observational datasheets or raw data.
If no comments are received from NMFS within 30 days, that phase's
draft final report will constitute the final report. If comments are
received, a final report for the given phase 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 IHAs (if issued), such
as an injury, serious injury or mortality, the Corps would 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 West Coast Regional Stranding Coordinator. The report
would 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).
[[Page 53698]]
Activities would not resume until NMFS is able to review the
circumstances of the prohibited take. NMFS would work with the Corps to
determine what is necessary to minimize the likelihood of further
prohibited take and ensure MMPA compliance. The Corps would not be able
to resume their activities until notified by NMFS via letter, email, or
telephone.
In the event that the Corps 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),
the Corps would immediately report the incident to the Chief of the
Permits and Conservation Division, Office of Protected Resources, NMFS,
and the West Coast Regional Stranding Coordinator. The report would
include the same information identified in the paragraph above.
Activities would be able to continue while NMFS reviews the
circumstances of the incident. NMFS would work with the Corps to
determine whether modifications in the activities are appropriate.
In the event that the Corps 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 these IHAs
(e.g., previously wounded animal, carcass with moderate to advanced
decomposition, or scavenger damage), the Corps would report the
incident to the Chief of the Permits and Conservation Division, Office
of Protected Resources, NMFS, and the West Coast Regional Stranding
Coordinator, within 24 hours of the discovery. The Corps would 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).
To avoid repetition, our analysis applies to all species listed in
Table 6, given that NMFS expects the anticipated effects of the planned
pile driving to be similar in nature. Where there are meaningful
differences between species or stocks, or groups of species, in
anticipated individual responses to activities, impact of expected take
on the population due to differences in population status, or impacts
on habitat, NMFS has identified species-specific factors to inform the
analysis.
NMFS does not anticipate that serious injury or mortality would
occur as a result of the Corps' planned activity. As stated in the
planned mitigation section, shutdown zones will be established and
monitored that equal or exceed calculated Level A harassment isopleths
during all pile driving activities.
Behavioral responses of marine mammals to pile driving during the
King Pile Marker Project are expected to be mild, short term, and
temporary. Marine mammals within the Level B harassment zones may not
show any visual cues they are disturbed by activities or they could
become alert, avoid the area, leave the area, or display other mild
responses that are not observable such as changes in vocalization
patterns. Given the short duration of noise-generating activities (less
than 90 minutes of combined daily impact and vibratory driving at 68
separate locations over 61 days, any harassment would be likely be
intermittent and temporary.
In addition, for all species there are no known biologically
important areas (BIAs) within the lower Columbia River and no ESA-
designated marine mammal critical habitat. The lower Columbia River
represents a very small portion of the total habitat available to the
pinniped species for which NMFS is proposing to authorize take. More
generally, there are no known calving or rookery grounds within the
project area, the project area represents a small portion of available
foraging habitat, and the duration of noise-producing activities
relatively is short, meaning impacts on marine mammal feeding for all
species should be minimal.
Any impacts on marine mammal prey that would occur during the
Corps' planned activity would have at most short-terms effects on
foraging of individual marine mammals while transiting between the
South Jetty at the Mouth of the Columbia River and Bonneville Dam
located 146 miles upstream. Better feeding opportunities exist at these
two locations which is why pinnipeds tend to congregate in these areas.
Therefore, indirect effects on marine mammal prey during the
construction are not expected to be substantial, and these
insubstantial effects would therefore be unlikely to cause substantial
effects on individual marine mammals or the populations of marine
mammals as a whole.
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;
The Corps would implement mitigation measures including
bubble curtains and soft-starts during impact pile driving as well as
shutdown zones that exceed Level A harassment zones for authorized
species, such that Level A harassment is neither anticipated nor
authorized;
Anticipated incidents of Level B harassment consist of, at
worst, temporary modifications in behavior;
There are no BIAs or other known areas of particular
biological importance to any of the affected stocks impacted by the
activity within the Columbia River estuary or lower Columbia River; and
The project area represents a very small portion of the
available foraging area for all marine mammal species and anticipated
habitat impacts are minimal.
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 planned monitoring and
mitigation measures, NMFS finds that the total marine mammal take from
the planned activity will have a negligible impact on
[[Page 53699]]
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 in the Marine Mammal Occurrence and Take Calculation and
Estimation section presents the number of animals that could be exposed
to received noise levels that may result in take by Level B harassment
from the Corps' planned activities. Our analysis shows that less than 9
percent of the Steller sea lion stock could be taken. Less than three
percent of harbor seal and less than one percent of California sea lion
are expected to be taken. Given that numbers for Steller sea lions were
derived from limited observation at Bonneville Dam, it is likely that
many of these takes will be repeated takes of the same animals over
multiple days. As such, the take estimate serves as a good estimate of
instances of take, but is likely an overestimate of individuals taken,
so actual percentage of stocks taken would be even lower. We also
emphasize the fact that the lower Columbia River represents a very
small portion of the stock's large range, which extends from southeast
Alaska to southern California. It is unlikely that one quarter of the
entire stock would travel in excess of 137 miles upstream to forage at
Bonneville Dam on the Columbia River.
Based on the analysis contained herein of the planned activity
(including 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
There are no relevant subsistence uses of the affected marine
mammal stocks or species implicated by this action.
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 IHA)
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)
No incidental take of ESA-listed species is authorized or expected
to result from this activity. Therefore, NMFS has determined that
formal consultation under section 7 of the ESA is not required for this
action.
Authorization
NMFS has issued an IHA to the Corps for the harassment of small
numbers of marine mammals incidental to the King Marker Project on the
Columbia River provided the previously mentioned mitigation,
monitoring, and reporting requirements are incorporated.
Dated: September 30, 2019.
Catherine Marzin,
Deputy Director, Office of Protected Resources, National Marine
Fisheries Service.
[FR Doc. 2019-21905 Filed 10-7-19; 8:45 am]
BILLING CODE 3510-22-P