[Federal Register Volume 83, Number 85 (Wednesday, May 2, 2018)]
[Notices]
[Pages 19243-19254]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-09238]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XF882


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Astoria Waterfront Bridge 
Replacement Project

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

ACTION: Notice; Issuance of an Incidental Harassment Authorization.

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SUMMARY: In accordance with the 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 of Astoria, Oregon, to incidentally harass, by Level B 
harassment only, marine mammals during construction activities 
associated with a waterfront bridges replacement project in Astoria, 
Oregon.

DATES: This authorization is effective from October 1, 2018 through 
September 30, 2019.

FOR FURTHER INFORMATION CONTACT: Amy Fowler, Office of Protected 
Resources, NMFS, (301) 427-8401. Electronic copies of the IHA and

[[Page 19244]]

supporting documents, as well as a list of the references cited in this 
document, may be obtained online at: https://www.fisheries.noaa.gov/node/23111. In case of problems accessing these documents, please call 
the contact listed above.

SUPPLEMENTARY INFORMATION:

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct the Secretary of Commerce (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 
authorization is provided to the public for review.
    An authorization for incidental takings shall be granted if NMFS 
finds that the taking will have a negligible impact on the species or 
stock(s), will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for subsistence uses (where 
relevant), and if the permissible methods of taking and requirements 
pertaining to the mitigation, monitoring and reporting of such takings 
are set forth.
    NMFS has defined ``negligible impact'' in 50 CFR 216.103 as ``. . . 
an impact resulting from the specified activity that cannot be 
reasonably expected to, and is not reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival.''
    The MMPA states that the term ``take'' means to harass, hunt, 
capture, kill or attempt to harass, hunt, capture, or kill any marine 
mammal. Except with respect to certain activities not pertinent here, 
the MMPA defines ``harassment'' as: Any act of pursuit, torment, or 
annoyance which (i) has the potential to injure a marine mammal or 
marine mammal stock in the wild (Level A harassment); or (ii) has the 
potential to disturb a marine mammal or marine mammal stock in the wild 
by causing disruption of behavioral patterns, including, but not 
limited to, migration, breathing, nursing, breeding, feeding, or 
sheltering (Level B harassment).

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 CE B4 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 
preliminarily determined that the issuance of the proposed IHA 
qualifies to be categorically excluded from further NEPA review.

Summary of Request

    On October 17, 2017, NMFS received a request from the City of 
Astoria (City), Oregon, for an IHA to take marine mammals incidental to 
replacement of bridges in downtown Astoria along the Columbia River. 
The application was considered adequate and complete on January 17, 
2018. The City's request was for take of California sea lions (Zalophus 
californianus), Steller sea lions (Eumetopias jubatus), and harbor 
seals (Phoca vitulina richardii) by Level B harassment only. Neither 
the City nor NMFS expect mortality to result from this activity and, 
therefore, an IHA is appropriate.

Description of the Specified Activity

    The City of Astoria is planning to replace three bridges connecting 
city streets to waterfront piers in the Columbia River. The bridges are 
currently supported by deteriorated timber piles, which will be removed 
and replaced with steel piles. Bridge replacement is scheduled to begin 
with above-water work to remove the superstructures of the bridges in 
October 2018. In-water pile removal and installation will occur over 80 
days between November 1, 2018 and February 28, 2019. Vibratory removal 
of 255 timber piles is expected to take 26 days while impact driving of 
74 permanent steel piles and installation and subsequent removal of 10 
temporary steel piles is expected to take 42 days. The remaining 12 
days of in-water work will be used to remove concrete footings and a 
concrete retaining wall along the riverbank. Additional above-water 
construction to replace the bridge superstructures will occur in March 
and April 2019.
    A detailed description of the planned bridge replacement project is 
provided in the Federal Register notice for the proposed IHA (83 FR 
7680; February 22, 2018). Since that time, no changes have been made to 
the planned construction 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 was published in the 
Federal Register on February 22, 2018 (83 FR 7680). During the 30-day 
public comment period, the Marine Mammal Commission (Commission) 
submitted a letter on March 21, 2018. The Commission provided comments 
as described below and concurred with NMFS's finding that recommended 
the issuance of an IHA to the City, subject to the inclusion of the 
mitigation, monitoring, and reporting measures.
    Comment 1: The Commission commented that NMFS' method of estimating 
takes from this project was inappropriate. Rather than multiplying the 
average count of pinnipeds from the South Jetty by months of activity, 
NMFS should have multiplied by days of activity. As a result, the take 
numbers proposed in the Federal Register notice (83 FR 7680; February 
22, 2018) were underestimated. The Commission recommended revising the 
take estimates to better reflect the likelihood of pinniped occurrence 
in the project area.
    Response 1: NMFS concurs with the Commission recommendation and has 
modified the authorized take limits to account for newly available 
site-specific data. These changes are described further in the ``Marine 
Mammal Occurrence'' and ``Take Calculation and Estimation'' sections in 
this notice. As a result of this modification, NMFS authorized the take 
of 33,736 California sea lions, 5,360 Steller sea lions, and 4,560 
harbor seals.
    Comment 2: The Commission requested clarification of certain issues 
associated with NMFS's notice that one-year renewals could be issued in 
certain limited circumstances and expressed concern that the process 
would bypass the public notice and comment requirements. The Commission 
also suggested that NMFS should discuss the possibility of renewals 
through a more general route, such as a rulemaking, instead of notice 
in a specific authorization. The Commission further recommended that if 
NMFS did not pursue a more general route, that the agency provide the 
Commission and the public with a legal analysis supporting our 
conclusion that this process is consistent with the requirements of 
101(a)(5)(D) of the MMPA.
    Response 2: The process of issuing a renewal IHA does not bypass 
the public

[[Page 19245]]

notice and comment requirements of the MMPA. 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. 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. NMFS has, however, modified the language for future proposed 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 will publish 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

    A detailed description of the species likely to be affected by the 
City's actions, including brief introductions to the species and 
relevant stocks as well as available information regarding population 
trends and threats, and information regarding local occurrence, are 
provided in the City's application and the Federal Register notice for 
the proposed IHA (83 FR 7680; February 22, 2018). 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 refer to 
additional species information available in the NMFS stock assessment 
reports for the Pacific and Alaska at http://www.nmfs.noaa.gov/pr/sars/region.htm.

                                         Table 1--Marine Mammals Potentially Present in the Vicinity of Astoria
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                               ESA/MMPA       Stock abundance
                                                                                status;       (CV, Nmin, most               Annual M/       Relative
           Common name              Scientific name           Stock          strategic (Y/    recent abundance      PBR       SI \3\    occurrence near
                                                                                N) \1\          survey) \2\                                 Astoria
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals
 and sea lions):
    California sea lion.........  Zalophus             U.S................  -; N            296,750 (N/A,            9,200        389  Likely.
                                   californianus.                                            153,337, 2011).
    Steller sea lion............  Eumetopias jubatus.  Eastern U.S........  -; N            41,638 (N/A,             2,498        108  Likely.
                                                                                             41,638, 2015).
Family Phocidae (earless seals):
    Pacific harbor seal.........  Phoca vitulina       Oregon/Washington    -; N            Unknown (0.12,          undet.       10.6  Likely.
                                   richardii.           Coast.                               24,732, 1999).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\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. For certain stocks, abundance estimates are actual counts of animals and there is no associated
  CV.
\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.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    The effects of underwater noise from vibratory and impact pile 
driving and airborne noise from superstructure construction for the 
bridge replacement project have the potential to result in behavioral 
harassment of marine mammals in the vicinity of the action area. The 
Federal Register notice for the proposed IHA (83 FR 7680; February 22, 
2018) included a discussion of the effects of the project and 
anthropogenic noise on marine mammals, therefore that information is 
not repeated here; please refer to the Federal Register notice (83 FR 
7680; February 22, 2018) for that information. We provide a summary 
here.
    The main impact associated with the bridge replacement project 
would be exposure to temporarily elevated sound levels and the 
associated direct effects on marine mammals (e.g., temporary hearing 
impairment, behavioral disturbance, and stress). The new bridges will 
be installed within the footprint of the existing bridges, therefore no 
new permanent impacts to habitats used by marine mammals would result 
from the project. Some short-term impacts to prey availability (e.g., 
fish) and minor impacts to the immediate substrate may occur as a 
result of increased turbidity from pile installation and removal but 
the effects are expected to be minimal. No critical habitat for any 
marine mammal species occurs in the project area.

Estimated Take

    This section provides an estimate of the number of incidental takes 
authorized by this IHA, which informs both NMFS' consideration of 
whether the number of takes is ``small'' 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 are by Level B harassment only, for individual 
marine mammals resulting from exposure to pile driving and construction 
activities. Based on the nature of the activity and

[[Page 19246]]

the anticipated effectiveness of the mitigation measures (i.e., 
shutdown--discussed in detail below in Proposed Mitigation section), 
Level A harassment is neither anticipated nor proposed to be 
authorized. As described previously, no mortality is anticipated or 
proposed to be authorized for this activity. Below we describe how the 
take is estimated.
    Described in the most basic way, 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. Below, we describe these 
components in more detail and present the proposed 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). Thresholds have also 
been developed identifying the received level of in-air sound above 
which exposed pinnipeds would likely be behaviorally harassed.
    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., 2011). 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 decibels (dB) re 1 micro pascal ([mu]Pa) root 
mean square (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. For in-air sounds, NMFS predicts that pinnipeds exposed 
above received levels of 100 dB re 20 [mu]Pa (rms) will be behaviorally 
harassed.
    The City's activities include 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 (Technical Guidance, 2016) 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 City's activities include the use of impulsive (impact pile 
driving) and non-impulsive (vibratory pile driving) sources.
    These thresholds were developed by compiling and synthesizing the 
best available science and soliciting input multiple times from both 
the public and peer reviewers to inform the final product, and are 
provided in Table 2 below. The references, analysis, and methodology 
used in the development of the thresholds are described in NMFS 2016 
Technical Guidance, which may be accessed at: https://www.fisheries.noaa.gov/resource/document/underwater-acoustic-thresholds-onset-permanent-and-temporary-threshold-shifts.

                     Table 2--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
                                                                   PTS onset thresholds
             Hearing group              ------------------------------------------------------------------------
                                                  Impulsive                         Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans...........  Lpk,flat: 219 dB;           LE,LF,24h: 199 dB.
                                          LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans...........  Lpk,flat: 230 dB;           LE,MF,24h: 198 dB.
                                          LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans..........  Lpk,flat: 202 dB;           LE,HF,24h: 173 dB.
                                          LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW); (Underwater)....  Lpk,flat: 218 dB;           LE,PW,24h: 201 dB.
                                          LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater)....  Lpk,flat: 232 dB;           LE,OW,24h: 219 dB.
                                          LE,OW,24h: 203 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 [mu]Pa, and cumulative sound exposure level (LE) has
  a reference value of 1[mu]Pa2s. 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.
Level B Harassment
    In-Air Disturbance during General Construction Activities--Level B 
behavioral disturbance may occur incidental to the use of construction 
equipment during general construction that is proposed in the dry, 
above water, or inland within close proximity to the river banks. These 
construction activities are associated with the removal and 
construction of the rail superstructures, and the removal of the 
existing concrete foundations and the 9th Street retaining wall. 
Possible equipment includes an excavator, crane, dump truck, and chain 
saw. It is estimated that the sound levels during these activities will 
range from 78 to 93

[[Page 19247]]

dB (rms) at 20 meters (m) from the sound source, with the loudest 
airborne noise produced by the use of a concrete saw (Hanan & 
Associates, 2014). These noise levels are based on acoustic data 
collected during the City of San Diego Lifeguard Station Demolition and 
Construction Monitoring project. Using the Spherical Spreading Loss 
Model (20logR), a maximum sound source level of 93 dB (rms) at 20 m, 
sound levels in-air would attenuate below the 90dB (rms) Level B 
harassment threshold for harbor seals at 28 m, and below the 100 dB 
(rms) threshold for all other pinnipeds at 9 m. Harbor seals are only 
present in the main river channel and are not expected to occur within 
28 m of the activity and are therefore not expected to be harassed by 
in-air sound. Additionally, the city will implement a 10 m shutdown 
zone for all general construction work to prevent injury from physical 
interaction with equipment. The City would therefore shut down 
equipment before hauled out sea lions could be acoustically harassed by 
the sound produced. No Level B harassment is expected to occur due to 
increased sounds from railway and roadway construction. However, sea 
lions may be disturbed by the presence of construction equipment and 
increased human presence during above-water construction.
    Although some piles may potentially be driven or removed in the dry 
due to tidal conditions, the City assumed all pile driving and removal 
will occur in water. The Level B harassment zone for in-water pile 
driving and removal is greater than the airborne Level B harassment 
zone so no airborne harassment is requested from pile driving or 
removal. All harassment due to pile driving and removal is assumed to 
be in-water.
    In-Water Disturbance during Vibratory Pile Removal--Level B 
behavioral disturbance may occur incidental to the use of a vibratory 
hammer due to propagation of underwater noise during the removal of the 
existing timber substructures. An estimated 255 timber piles will need 
to be removed to facilitate construction of the three new crossings. It 
is anticipated that the contractor will need to utilize a vibratory 
hammer during extraction. Removal via vibratory hammer will result in 
the greatest amount of underwater noise during construction and will be 
the farthest reaching extent of aquatic impacts during pile removal 
activities. We note that some pile removal will occur in the dry 
(depending on tidal stage); however, we conservatively assumed all work 
would occur in-water since it is not feasible to determine how many 
piles would be removed in the dry. When piles are removed at lower 
tidal stages, we do not anticipate sound to propagate as far or, in the 
case of no water, at all.
    Washington State Department of Transportation (WSDOT) monitored 
underwater noise during the removal of three 12-in timber dolphin piles 
at Port Townsend (Laughlin 2011a). Most of the timber piles to be 
removed in this project are 12-in but some may be up to 14-in. Average 
noise levels during vibratory removal of the wood piles were measured 
at 150 dB (rms) at 16 m from the source. The Practical Spreading Loss 
Model (15logR) was used to calculate the in-water Level B harassment 
zone during vibratory pile removal. Using a measurement of 150dB at 16 
m, a 1,600 m Level B harassment zone (120 dB rms threshold) is expected 
for vibratory pile removal activities. Based on the contours of the 
shoreline and 1,600 m Level B harassment zone, a total of 4.5 square 
kilometers (km\2\) is expected to be ensonified due to vibratory pile 
removal (see Figure 10 in application) (Table 7).
    In-Water Disturbance during Impact Pile Driving--Level B behavioral 
disturbance may occur incidental to the use of an impact hammer due to 
the propagation of underwater noise during the installation of 
permanent and temporary steel piles. The City will install a total of 
74 24-in and 10 16-in steel piles. The City used the sound source 
levels from 24-in piles only to estimate the Level B harassment zone 
due to pile driving as the sound source levels from 24-in piles are 
greater than those of 16-in piles. The City will use the Level B 
harassment zone created by installation of 24-in piles during the 
installation of 16-in piles to be conservative.
    Based on the most recent WSDOT data, the unmitigated sound pressure 
level associated with impact pile driving 24-in steel piles is 194 dB 
RMS at 10 m (WSDOT 2016). The contractor will be required to use a 
bubble curtain device during impact pile driving in compliance with the 
Federal Aid Highway Program (FAHP) Programmatic Biological Opinion, 
which will be utilized for ESA coverage for listed salmonids. Use of a 
bubble curtain device was assumed to decrease initial sound levels by 
10 dB (Reyff, 2007), resulting in an initial sound pressure level (SPL) 
of 184 dB RMS at 10 m from the source. Using the values from WSDOT in 
the Practical Spreading Loss Model (15logR), the distance to the 160 dB 
behavioral disturbance threshold is calculated to be 398 m from the 
pile when a noise attenuation device is used (Table 3) as opposed to 
1,848 m when a device is not used. The use of a noise attenuation 
device would shrink the distance at which noise exceeds the thresholds 
by approximately 80 percent, resulting in a significantly smaller area 
of potential impact. With a 398 m Level B harassment zone, a total of 
0.40 km\2\ is expected to be ensonified by impact pile driving (Figure 
11 in application).

                     Table 3--Inputs and Resulting Distances to Level B Harassment Isopleths
----------------------------------------------------------------------------------------------------------------
                                                                    Propagation
           Activity              SL (distance    Threshold level       loss           Level B      Level B area
                                   measured)                        coefficient    isopleth (m)       (km\2\)
----------------------------------------------------------------------------------------------------------------
Vibratory pile driving/        150 dB (16 m)...  120 dB re 1                  15           1,600             4.5
 removal.                                         [micro]Pa.
Impact pile driving (24-in     184 dB (10 m)     160 dB re 1                  15             398             0.4
 piles).                        \a\.              [micro]Pa.
General Construction (in-air)  93 dB (20 m)....  100 dB re 20                 20             9 m             n/a
                                                  [micro]Pa \b\.
----------------------------------------------------------------------------------------------------------------
a Proxy SL with 10 dB reduction due to bubble curtain.
b 100 dB re 20 [micro]Pa airborne threshold applies only to sea lions. The distance to the 90 dB re 20[micro]Pa
  applicable to harbor seals is 28 m but harbor seals are not expected to be harassed by airborne sound, as
  described above.

Level A Harassment
    When 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

[[Page 19248]]

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 will result in some degree of overestimate of Level A 
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 impact and vibratory pile 
driving), 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 permanent threshold shift (PTS). Inputs 
used in the User Spreadsheet, and the resulting isopleths are reported 
below.

          Table 4--PTS Isopleth Data for Vibratory Pile Removal
------------------------------------------------------------------------
 
------------------------------------------------------------------------
Source Level (RMS SPL)..................................             150
Activity Duration (hours) within 24-hr period...........               8
Activity Duration (seconds).............................          28,800
10 Log (Duration).......................................           44.59
Propagation (xLogR).....................................              15
Distance of source level measurement (m)................              16
------------------------------------------------------------------------


       Table 5--Resulting PTS Isopleths for Vibratory Pile Driving
------------------------------------------------------------------------
                                              Phocid          Otariid
                                             pinnipeds       pinnipeds
------------------------------------------------------------------------
SELcum Threshold........................             210             219
PTS Isopleth to Threshold (meters)......             4.9             0.3
------------------------------------------------------------------------


           Table 6--PTS Isopleth Data for Impact Pile Driving
------------------------------------------------------------------------
 
------------------------------------------------------------------------
Source Level (Single Strike/shot SEL)...................             168
(a) Number of strikes in 1 h OR (b) Number of strikes                250
 per pile...............................................
(a) Activity Duration (h) within 24-h period OR (b)                    4
 Number of piles per day................................
Propagation (xLogR).....................................              15
Distance of single strike SEL measurement (meters)......              10
------------------------------------------------------------------------


        Table 7--Resulting PTS Isopleths for Impact Pile Driving
------------------------------------------------------------------------
                                              Phocid          Otariid
                                             pinnipeds       pinnipeds
------------------------------------------------------------------------
SELcum Threshold........................             185             203
PTS Isopleth to Threshold (m)...........            53.4             3.9
------------------------------------------------------------------------

    The resulting small PTS isopleths assume an animal would remain 
stationary at that distance for the duration of the activity. Given the 
extended durations and due to the relatively small distances to PTS 
onset from each activity, and the mitigation measures (See 
``Mitigation'') proposed by the City, Level A take is neither expected 
nor authorized.

Marine Mammal Occurrence

    In this section we provide the information about the presence, 
density, or group dynamics of marine mammals that will inform the take 
calculations.
    In the Federal Register notice of proposed IHA (83 FR 7680; 
February 22, 2018), takes of marine mammals were estimated using counts 
from 2000-2014 by WDFW at the South Jetty at the mouth of the Columbia 
River. At the time of publication, these counts were believed to be the 
best available data on pinniped occurrence in the lower Columbia River. 
After publication of the Federal Register notice (83 FR 7680; February 
22, 2018), NMFS learned of Oregon Department of Fish and Wildlife 
(ODFW) aerial surveys of pinnipeds at the East Mooring Basin 
(approximately one mile upstream from the project site) and Desdemona 
Sands (approximately one mile downstream from the project site). 
Estimated takes of California sea lions were recalculated using data 
generated by those surveys (ODFW; Bryan Wright, pers. comm., March 
2018).
    Aerial surveys of the East Mooring Basin in Astoria from 2011 to 
2017 were used to calculate take of California sea lions. Maximum daily 
counts of California sea lions at the East Mooring Basin ranged from 3 
in July 2016 to 3,834 in March 2016. In addition to ODFW aerial 
surveys, the City conducted opportunistic surveys of pinnipeds at the 
bridge sites in December 2017. A maximum of four California sea lions 
were observed in the water surrounding the bridges and piers. 
Additional California sea lions were heard vocalizing from the 
riverbanks under the bridges but the number of sea lions could not be 
determined. A conservative estimate of 16 California sea lions per day 
may be hauled out on the riverbanks and subject to harassment from 
above-water construction work.
    Counts of Steller sea lions at the East Mooring Basin typically 
numbered in the single digits (B. Wright, pers. comm., March 2018). 
However, there are typically dozens of Steller sea lions at the 
Bonneville Dam and a few individuals at Willamette Falls. While the sea 
lions observed at Bonneville and Willamette are often the same 
individuals seen daily, these animals must transit past Astoria at some 
point in their travels from the Pacific to the

[[Page 19249]]

upper Columbia River (B. Wright, pers. comm., March 2018).
    Numbers of harbor seals hauled out at Desdemona Sands have been 
reported to reach into the thousands (Profita 2015) but specific counts 
were unavailable. Without counts of harbor seals closer to the project 
site, the maximum average count of harbor seals at the South Jetty (57 
seals; WDFW 2014) is used to calculate take.

Take Calculation and Estimation

    Here we describe how the information provided above is brought 
together to produce a quantitative take estimate.
    In the Federal Register notice for the proposed IHA (83 FR 7680; 
February 22, 2018), take of each species was calculated using average 
counts of pinnipeds at the South Jetty (WDFW 2014). Average monthly 
counts were multiplied by months of activity to determine the total 
take estimation. During the public comment period, we received 
information that although the WDFW counts were presented as average 
number of pinnipeds per month, the numbers were actually daily counts 
and therefore should have been multiplied by days of activity. The take 
limits in the final authorization were calculated by multiplying 
maximum counts of pinnipeds by days of activity.
    Although three species of pinniped occur in the vicinity of the 
project, they do not occur in equal numbers. Harbor seals and Steller 
sea lions do not haul-out near the project area and would only be 
harassed if they are transiting through the in-water Level B harassment 
zone (1,600 m for vibratory pile removal, 398 m for impact pile 
driving) at the time of pile driving. Because harbor seals and Steller 
sea lions do not have the potential to be harassed when hauled-out (in-
air), they would only be harassed during the in-water work period 
(November through February).
    California sea lions are the most commonly observed marine mammal 
in the area, and are known to haul out on the riverbanks and structures 
near the bridges. California sea lions may be harassed by underwater 
sound resulting from vibratory pile removal and impact pile driving (at 
the distances listed above) as well as airborne sound resulting from 
roadway and railway demolition and construction. As such, California 
sea lions may be subject to both in-water and in-air sources of 
harassment (October through April).
    Using the highest sound source (concrete saw, 93 dBrms 
re: 20 [micro]Pa at 20 m), the isopleth to Level B harassment from 
airborne noise (100 dB re: 20 [micro]Pa) is 9 m. The City is proposing 
a 10 m shutdown zone during all railway and roadway above-water 
construction to prevent injury from physical interaction with equipment 
(see ``Mitigation''). The City would therefore shut down equipment 
before sea lions would be acoustically harassed by the sound produced 
and no Level B acoustic harassment would occur. However, the City 
anticipates that California sea lions hauled out on the banks of the 
river in the vicinity of the construction work may be visually 
disturbed by the presence of construction equipment and may flush, 
resulting in Level B take. Therefore, we have authorized take of 
California sea lions during the above-water work period (October 2018 
and March-April 2019).
    While harbor seals and Steller sea lions would only be harassed 
during the in-water work period (November through February), California 
sea lions may be harassed over the entire duration of the project 
(October through April). To determine the estimated exposure and take 
of harbor seals, the maximum average daily count of harbor seals at the 
South Jetty (57 seals) was multiplied by planned days of in-water work 
(80 days). Similarly, the maximum number of Steller sea lions observed 
at the Bonneville Dam (63; USACE 2017) and Willamette Falls (4; ODFW 
2017) were multiplied by 80 days of in-water work to account for the 
maximum number of Steller sea lions likely to be in the Columbia River 
transiting past Astoria each day (Table 8).

                         Table 8--Take Calculation of Harbor Seals and Steller Sea Lions
----------------------------------------------------------------------------------------------------------------
                                                                   Maximum daily      Days of       Total take
                             Species                                   count         activity        (Level B)
----------------------------------------------------------------------------------------------------------------
Harbor seal.....................................................          \1\ 57              80           4,560
Steller sea lion................................................          \2\ 67              80           5,360
----------------------------------------------------------------------------------------------------------------
\1\ WDFW 2014.
\2\ 63 sea lions at Bonneville Dam + 4 sea lions at Willamette Falls (USACE 2017; ODFW 2017).

    Take of California sea lions was calculated by multiplying the 
average maximum daily count per month by the days of activity in each 
month (Table 9).

                                Table 9--Take Calculation of California Sea Lions
----------------------------------------------------------------------------------------------------------------
                                                                                                    Total takes
                              Month                                Daily average   Days of work      per month
                                                                    maximum \1\    in month \2\      (Level B)
----------------------------------------------------------------------------------------------------------------
October.........................................................              16              22             352
November........................................................             141              20           2,817
December........................................................             135              20           2,690
January.........................................................             408              21           8,577
February........................................................             980              19          18,612
March...........................................................              16              21             336
April...........................................................              16              22             352
                                                                 -----------------------------------------------
    Total Takes.................................................  ..............  ..............          33,736
----------------------------------------------------------------------------------------------------------------
\1\ B. Wright, pers. comm.
\2\ Days of work excludes weekends and holidays.


[[Page 19250]]

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.

Mitigation for Marine Mammals and Their Habitat

    General Construction Measures--All construction activities shall be 
performed in accordance with the current Oregon Department of 
Transportation (ODOT) Standard Specifications for Construction, the 
Contract Plans, and the Project Special Provisions. In addition, the 
following general construction measures shall be adhered to:
     All work below the highest measured tide shall be 
completed during the ODFW prescribed in-water work period of November 1 
through February 28;
     All work shall be performed according to the requirements 
and conditions of the regulatory permits issued by federal, state, and 
local governments. Seasonal restrictions, i.e., work windows, shall be 
applied to the Project to avoid or minimize potential impacts to listed 
or proposed species based on agreement with, and the regulatory permits 
issued by Department of State Lands, and U.S. Army Corps of Engineers 
(USACE) in consultation with NMFS. The City shall comply with all 
stipulations from the FAHP Biological Opinion for salmonids (i.e., 
using air bubble curtains);
     The City shall have an inspector onsite during 
construction. The role of the inspector is to ensure compliance with 
the construction contract and other permits and regulations. The onsite 
inspector shall also perform marine mammal monitoring duties when 
protected species observers (PSOs) are not onsite (See Proposed 
Monitoring section);
     To ensure no contaminants enter the water, mobile heavy 
equipment shall be stored in a staging area at least 150 ft from the 
river or in an isolated hard zone. Equipment shall be inspected daily 
for fluid leaks before leaving the staging area. Stationary equipment 
operated within 150 ft of the river shall be maintained and protected 
to prevent leaks and spills. Erosion and sediment control BMPs shall be 
installed prior to initiating and construction activities; and
     The contractor shall be responsible for the preparation of 
a Pollution Control Plan (PCP). The PCP shall designate a professional 
on-call spill response team, and identify all contractor activities, 
hazardous substances used, and wastes generated. The PCP shall describe 
how hazardous substances and wastes will be stored, used, contained, 
monitored, disposed of, and documented.
    Pile Removal and Installation BMPs--The following mitigation 
measures shall be implemented to minimize disturbance during pile 
removal and installation activities:
     An air bubble system shall be employed during impact 
installation unless the piles are driven on dry areas;
     The contractor shall implement a soft-start procedure for 
impact pile driving activities. The objective of a soft-start is to 
provide a warning and/or give animals in close proximity to pile 
driving a chance to leave the area prior to an impact driver operating 
at full capacity, thereby exposing fewer animals to loud underwater and 
airborne sounds. A soft-start procedure shall be used at the beginning 
of each day that pile installation activities are conducted (i.e., for 
impact driving, an initial set of three strikes would be made by the 
hammer at 40 percent energy, followed by a one minute wait period, then 
two subsequent 3-strike sets at 40 percent energy, with one minute 
waiting periods, before initiating continuous driving);
     Monitoring of marine mammals shall take place starting 30 
minutes before construction begins until 30 minutes after construction 
ends (See Proposed Monitoring);
     Before beginning vibratory pile removal activities, the 
City shall establish a 15 m shutdown zone to protect marine mammals 
from Level A harassment;
     Before beginning impact pile driving activities, the City 
shall establish a 55 m shutdown zone to protect marine mammals from 
Level A harassment;
     Before beginning any in-water work (not including pile 
driving/removal) and any above-water construction activities, the City 
shall establish a 10 m Level A shutdown zone to prevent injury from 
physical interaction with construction equipment;
     The City shall shut down operations if a marine mammal is 
sighted within or approaching the shutdown zone until the marine mammal 
is sighted moving away from the shutdown zone, or if not sighted for 15 
minutes after the shutdown;
     If a species for which authorization has been not been 
granted or for which authorization has been granted but the take limit 
has been met approaches or enters the Level B harassment zone, 
construction activity must cease and the City shall contact the Office 
of Protected Resources, NMFS;
     If the shutdown zone is obscured by poor lighting 
conditions, pile driving shall not be initiated until the entire zone 
is visible; and
     In-water work shall only commence once observers have 
declared the shutdown zone clear of marine mammals.
    Based on our evaluation of the applicant's proposed 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.

[[Page 19251]]

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 
proposed action area. Effective reporting is critical both to 
compliance and to 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

    The following marine mammal monitoring measures are included in the 
IHA.
    (1) Protected Species Observers: The City shall employ two 
qualified PSOs to monitor the extent of the Region of Activity for 
marine mammals. Qualifications for marine mammal observers include:
    a. Visual acuity in both eyes (correction is permissible) 
sufficient for discerning moving targets at the water's surface with 
ability to estimate target size and distance. Use of binoculars is 
necessary to correctly identify the target;
    b. Advanced education (at least some college level course work) in 
biological science, wildlife management, mammalogy, or related fields 
(bachelor's degree or higher is preferred but not required);
    c. Experience or training in the field identification of marine 
mammals (cetaceans and pinnipeds);
    d. Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations;
    e. 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;
    f. Experience and ability to conduct field observations and collect 
data according to assigned protocols (this may include academic 
experience); and
    g. Writing skills sufficient to prepare a report of observations 
that would include such information as the number and type of marine 
mammals observed; the behavior of marine mammals in the project area; 
dates and times when observations were conducted; dates and times when 
in-water construction activities were conducted; and dates and times 
when marine mammals were present at or within the defined Region of 
Activity.
    (2) Monitoring Schedule: PSOs shall be present onsite during IWW 
construction activities as follows:
    a. During vibratory pile removal activities:
    i. Two NMFS qualified observers shall be onsite the first day of 
removal at each bridge, one NMFS qualified observer shall be onsite 
every third day thereafter.
    ii. One NMFS qualified observer shall be stationed at the best 
practicable land-based vantage point to observe the downstream portion 
of the disturbance zone, and the other positioned at the best 
practicable land-based vantage point to monitor the upstream portion of 
the disturbance zone.
    iii. When PSOs are not onsite, the contractor's onsite inspector 
shall be trained in species identification and monitoring protocol, and 
shall be onsite during all pile removal activities to ensure that no 
species enter the 15 m shutdown zone.
    b. During pile driving activities:
    i. Two NMFS qualified observers shall be onsite the first two days 
of pile driving at each bridge, and every third day thereafter.
    ii. One NMFS observer shall be stationed at the best practicable 
land-based vantage point to observe the downstream portion of the 
disturbance and exclusion zones, and the other positioned at the best 
practicable land-based vantage point to monitor the upstream portion of 
the disturbance and exclusion zones.
    iii. When PSOs are not onsite, the contractor's onsite inspector 
shall be trained in species identification and monitoring protocol, and 
shall be onsite during all pile driving activities to ensure that no 
species enter the shutdown zone.
    c. During in-water substructure demolition activities (not 
including pile driving/removal) and above-water superstructure 
demolition and construction activities:
    i. One NMFS qualified observer shall be onsite once a week to 
monitor the shutdown zone within 10 m of the construction site.
    ii. When PSO is not on-site, the contractor's inspector shall be 
trained in species identification and monitoring protocol, and shall be 
onsite during all construction activities to ensure that no species 
enter the 10 m shutdown zone during superstructure demolition and 
construction activities.
    (3) Monitoring Protocols: PSOs shall monitor marine mammal presence 
within the shutdown zone and Level B harassment zones per the following 
protocols:
    a. A range finder or hand-held global positioning system device 
shall be used by PSOs to ensure that the defined shutdown zones are 
fully monitored and the Level B ZOIs monitored to the best extent 
practicable.
    b. A 30-minute pre-construction marine mammal monitoring period 
shall be required before the first pile driving or pile removal of the 
day. A 30-minute post-construction marine mammal monitoring period 
shall be required after the last pile driving or pile removal of the 
day. If the contractor's personnel take a break between subsequent pile 
driving or pile removal for more than 30 minutes, then additional pre-
construction marine mammal monitoring shall be required before the next 
start-up of pile driving or pile removal.
    c. If marine mammals are observed, the following information shall 
be documented:
    i. Species of observed marine mammals;

[[Page 19252]]

    ii. Number of observed marine mammal individuals;
    iii. Life stages of marine mammals observed;
    iv. Behavioral habits, including feeding, of observed marine 
mammals, in both presence and absence of activities;
    v. Location within the Region of Activity; and
    vi. Animals' reaction (if any) to pile driving activities or other 
construction-related stressors including:
    1. Impacts to the long-term fitness of the individual animal, if 
any
    2. Long-term impacts to the population, species, or stock (e.g., 
through effects on annual rates of recruitment or survival), if any
    vii. Overall effectiveness of mitigation measures
    d. During vibratory pule removal and impact driving, qualified PSOs 
shall monitor the Level B harassment zones from the best practicable 
land-based vantage point to observe the downstream and upstream 
portions of the disturbance zone according to the above schedule.
    e. PSOs shall use binoculars to monitor the Level B harassment 
zone.
    f. PSOs shall keep a running tally of takes of each marine mammal 
species authorized by extrapolating the observed takes to the days when 
monitoring did not occur. The City shall notify the Office of Protected 
Resources, NMFS if takes of any species come with five percent of the 
take limits established in the IHA.

Reporting

    (1) The City shall provide NMFS with a draft monitoring report 
within 90 days of the conclusion of the construction work. This report 
shall detail the monitoring protocol, summarize the data recorded 
during monitoring, and estimate the number of marine mammals that may 
have been harassed.
    (2) If comments are received from the NMFS West Coast Regional 
Administrator or NMFS Office of Protected Resources on the draft 
report, a final report shall be submitted to NMFS within 30 days 
thereafter. If no comments are received from NMFS, the draft report 
will be considered to be the final report.
    (3) In the unanticipated event that the construction activities 
clearly cause the take of a marine mammal in a manner prohibited by the 
NMFS authorization, such as an injury, serious injury, or mortality), 
the City shall immediately cease all operations and immediately report 
the incident to the Chief, Permits and Conservation Division, Office of 
Protected Resources, and the West Coast Regional Stranding Coordinator, 
(206) 526-4747. The report must include the following information:
    a. Time, date, and location (latitude/longitude) of the incident;
    b. Description of the incident;
    c. Status of all sound source use in the 24 hours preceding the 
incident;
    d. Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, visibility, and water depth);
    e. Description of marine mammal observations in the 24 hours 
preceding the incident;
    f. Species identification or description of the animal(s) involved, 
including life stage and the fate of the animal(s); and
    g. Photographs or video footage of the animal(s) (if equipment is 
available).
    Activities shall not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS shall work with the City to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. Activities may not be 
resumed until notified by NMFS via letter, email, or telephone.
    (4) In the event that the City discovers an injured or dead marine 
mammal, and the lead PSO determines that the cause of injury or death 
is unknown and the death is relatively recent (i.e., in less than a 
moderate state of decay as described in the next paragraph), the City 
shall immediately report the incident to the Chief, Permits and 
Conservation Division, Office of Protected Resources, NMFS, and the 
West Coast Regional Stranding Coordinators. The report must contain the 
same information identified above. Activities may continue while NMFS 
reviews the circumstances of the incident. NMFS will work with the City 
to determine whether modifications in the activities are appropriate.
    (5) In the event that the City 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), the City shall report the incident 
to the Chief, Permits and Conservation Division, Office of Protected 
Resources, NMFS, and the West Coast Regional Stranding Coordinators, 
within 24 hours of the discovery. The City shall provide photographs or 
video footage (if available) or other documentation of the stranded 
animal sighting to NMFS and the Marine Mammal Stranding Network. The 
City can continue its operations under such a case.

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, the discussion of our analyses applies to all 
three species authorized to be taken by this project (California sea 
lion, Steller sea lion, and harbor seal), given that the anticipated 
effects of this activity on these different marine mammal stocks are 
expected to be similar. There is little information about the nature or 
severity of the impacts, or the size, status, or structure of any of 
these species or stocks that would lead to a different analysis for 
this activity.
    Authorized takes are expected to be limited to short-term Level B 
harassment. Marine mammals present in the vicinity of the action area 
and taken by Level B harassment would most likely show overt brief 
disturbance (e.g., startle reaction, flushing) and avoidance of the 
area from elevated noise levels during pile removal and installation 
and railway superstructure construction. The project is not expected to 
have a significant adverse effect on affected marine mammal habitat, as 
discussed in

[[Page 19253]]

detail in the ``Anticipated Effects on Marine Mammal Habitat'' section. 
There is no critical habitat in the vicinity of the project and the 
project activities would not permanently modify existing marine mammal 
habitat. The impacts to marine mammal habitat from the construction 
actions are expected to be temporary and include increased human 
activity and noise levels, minimal impacts to water quality, and 
negligible changes in prey availability near the individual bridge 
sites. The project may benefit marine mammal habitat by removing 
several hundred treated timber piles from the Columbia River.
    Impacts to pinnipeds are expected to be minor and temporary. The 
area likely impacted by the construction is relatively small compared 
to the available habitat in the river. Pinnipeds in the vicinity are 
likely habituated to high levels of human activity as the Astoria 
waterfront is a highly developed area. Exposures to elevated sound 
levels produced during pile driving and removal activities may cause 
behavioral responses by an animal, but they are expected to be minor 
and temporary. Animals may become alert, avoid the area, leave the 
area, or show no observable response. Given the short daily duration of 
noise-generating activities and the limited season of in-water work, 
any harassment would be temporary. For California and Steller sea 
lions, sub-adult and adult males could be harassed during construction 
activities. For harbor seals, sub-adult and adult males and/or females 
could be harassed during construction activities. The project occurs 
outside of known pupping periods for all species, and there are no 
known rookeries within the region of activity. Therefore, no pups or 
breeding adults are expected to be affected by the project activities.
    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 injury is anticipated or authorized;
     No serious injury or mortality is anticipated or 
authorized;
     In-water work is limited to a four-month period, and 
likely only 80 days within that time;
     No permanent effects to marine mammal habitat or prey is 
expected;
     Marine mammals are currently exposed to high human use 
area and are likely habituated to disturbance;
     Any impacts from the project are expected to result in 
short-term, mild behavioral reactions such as avoidance or flushing;
     There are no known important feeding, pupping, or other 
areas of biological significance in the project area; and
     The project affects only a small percentage of each stock 
of marine mammal affected, and only in a limited portion of their 
overall range.
    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 proposed monitoring and 
mitigation measures, NMFS finds that the total marine mammal take from 
the proposed 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 section 101(a)(5)(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 10--Authorized Pinniped Take, by Level B Harassment
------------------------------------------------------------------------
                                            Authorized      Percent of
                                               take            stock
------------------------------------------------------------------------
California Sea Lion.....................          33,736            11.4
Steller Sea Lion........................           5,360            12.9
Harbor Seal.............................           4,560            18.4
------------------------------------------------------------------------

    The number of instances of take of each stock proposed to be taken 
as a result of this project is less than 20 percent of the total stock 
(Table 10). Additionally, the number of takes requested is based on the 
number of estimated exposures, not necessarily the number of 
individuals exposed. Pinnipeds may remain in the general area of the 
project sites and the same individuals may be harassed multiple times 
over multiple days, rather than numerous individuals harassed once. 
Therefore, the percent of stock may be less since the numbers 
represented in Table 10 assume distinct individuals.
    Based on the analysis contained herein of the proposed activity 
(including the proposed 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. Therefore, NMFS has 
determined that the total taking of affected species or stocks would 
not have an unmitigable adverse impact on the availability of such 
species or stocks for taking for subsistence purposes.

Endangered Species Act (ESA)

    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 the NMFS West Coast Region 
Protected Resources Division Office, whenever we propose to authorize 
take for endangered or threatened species.
    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.

[[Page 19254]]

Authorization

    As a result of these determinations, NMFS has issued an IHA to the 
City for the harassment of small numbers of California sea lions, 
Steller sea lions, and Pacific harbor seals incidental to construction 
activities related to bridge replacements in Astoria, Oregon, provided 
the previously mentioned mitigation, monitoring, and reporting 
requirements are incorporated.

    Dated: April 26, 2018.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2018-09238 Filed 5-1-18; 8:45 am]
 BILLING CODE 3510-22-P