[Federal Register Volume 82, Number 210 (Wednesday, November 1, 2017)]
[Notices]
[Pages 50628-50638]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-23748]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XF574


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to U.S. 101/Chehalis River Bridge--
Scour Repair in Washington State

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 we have issued an incidental harassment authorization (IHA) to 
Washington State Department of Transportation (WSDOT) to take small 
numbers of marine mammals, by harassment, incidental to U.S. 101/
Chehalis River Bridge--Scour Repair in Washington State.

DATES: This authorization is valid from July 1, 2018, through June 30, 
2019.

FOR FURTHER INFORMATION CONTACT: Shane Guan, Office of Protected 
Resources, NMFS, (301) 427-8401. Electronic copies of the application 
and supporting documents, as well as the issued IHA, may be obtained 
online at: www.nmfs.noaa.gov/pr/permits/incidental/construction.htm. In 
case of problems accessing these documents, please call the contact 
listed above.

SUPPLEMENTARY INFORMATION:

Background

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

    Issuance of an MMPA 101(a)(5)(D) authorization requires compliance 
with the National Environmental Policy Act.
    NMFS determined the issuance of the proposed IHA is consistent with 
categories of activities identified in CE B4 (issuance of incidental 
harassment authorizations under section 101(a)(5)(A) and (D) of the 
MMPA for which no serious injury or mortality is

[[Page 50629]]

anticipated) of the Companion Manual for NAO 216-6A and we have not 
identified any extraordinary circumstances listed in Chapter 4 of the 
Companion Manual for NAO 216-6A that would preclude this categorical 
exclusion.

Summary of Request

    NMFS received a request from WSDOT for an IHA to take marine 
mammals incidental to U.S. 101/Chehalis River Bridge--Scour Repair in 
the State of Washington. WSDOT's request was for harassment only and 
NMFS concurs that serious injury or mortality is not expected to result 
from this activity. Therefore, an IHA is appropriate.
    In November 2016, WSDOT submitted a request to NMFS requesting an 
IHA for the possible harassment of small numbers of marine mammal 
species incidental to U.S. 101/Chehalis River Bridge-Scour Repair in 
Washington State, between July 16 to September 30, 2018. WSDOT 
subsequently updated its project scope and submitted a revised IHA 
application on July 5, 2017. NMFS determined the IHA application was 
complete on July 14, 2017. NMFS issued an IHA to WSDOT to take by Level 
B harassment of the following marine mammal species: Harbor seal (Phoca 
vitulina); California sea lion (Zalophus californianus); Steller sea 
lion (Eumetopias jubatus); gray whale (Eschrichtius robustus); and 
harbor porpoise (Phocoena phocoena).

Description of Proposed Activity

Overview

    WSDOT is proposing to repair an area of scour associated with Pier 
14 of the U.S. 101 Chehalis River Bridge (Figures 1-3 and 1-4 in the 
IHA application). The bridge foundation at Pier 14 is ``scour 
critical'' due to the bridge foundation being unstable for calculated 
scour depths. The southwest quadrant of Pier 14 is undermined by scour 
void as much as 8 feet deep, and some of the untreated timber pilings 
have been directly exposed to river/estuary water since 2008. Marine 
borers may weaken enough pilings to require more extensive pier repair 
if this project is not built in the near future. In addition, the 
footing and seal are exposed at the other three quadrants of Pier 14.
    The purpose of the U.S. 101/Chehalis River Bridge Project is to 
make the bridge foundation stable for calculated scour depths, protect 
the foundation from further scour by removing debris, filling the scour 
void under Pier 14 with cementitious material (to protect the pilings 
from marine borers), and filling the scour hole and protecting the pier 
with scour resistant material.

Dates and Duration

    Due to NMFS and the U.S. Fish and Wildlife Service (USFWS) in-water 
work timing restrictions to protect ESA-listed salmonids, planned WSDOT 
in-water construction is limited each year to July 16 through February 
15. For this project, in-water construction is planned to take place 
between July 16 to September 30, 2018. The total worst-case time for 
pile installation and removal is 50 hours over 12 days (Table 1).

Specified Geographic Region

    The U.S. 101 Chehalis River Bridge is located in the City of 
Aberdeen, Grays Harbor County, Washington (Figure 1-1 in the IHA 
application). The bridge is located in Township 17 North, Range 9 West, 
Section 9, where the Chehalis River enters Grays Harbor. Land use in 
the Aberdeen area is a mix of residential, commercial, industrial, and 
open space and/or undeveloped lands (Figure 1-2 in the IHA 
application).

Detailed Description of In-Water Pile Driving Associated With the U.S. 
101 Chehalis River Bridge Repair Project

    The proposed project involves noise production that may affect 
marine mammals: Vibratory hammer driving and removal. Details of the 
pile driving and pile removal activities are provided in the Federal 
Register notice (82 FR 37426; August 10, 2017) for the proposed IHA and 
is summarized in Table 1 below.

                         Table 1--Summary of In-Water Pile Driving and Removal Durations
----------------------------------------------------------------------------------------------------------------
                                                     Pile size                    Duration (min)     Duration
            Method                  Pile type         (inch)         Pile No.        per pile         (days)
----------------------------------------------------------------------------------------------------------------
Vibratory driving.............  Steel H pile....              12               6              30               1
Vibratory driving.............  Sheet pile......  ..............              44              30               5
Vibratory removal.............  Steel H pile....              12               6              30               1
Vibratory removal.............  Sheet pile......  ..............              44              30               5
                                                 ---------------------------------------------------------------
    Total.....................  ................  ..............  ..............  ..............              12
----------------------------------------------------------------------------------------------------------------

Comments and Responses

    A notice of NMFS' proposal to issue an IHA was published in the 
Federal Register on August 10, 2017 (82 FR 37426). During the 30-day 
public comment period, NMFS received a comment letter from the Marine 
Mammal Commission (Commission). No other comments were received. 
Specific comments and responses are provided below.
    Comment 1: The Commission recommends that NMFS (1) determine 
whether action proponents would be required to implement delay or shut-
down procedures for vibratory pile driving and removal and (2) include 
standard mitigation, monitoring, and reporting measures consistently 
for all authorizations involving those actions.
    Response: As stated in the Federal Register notice for the proposed 
IHA (82 FR 37426, August 10, 2017), WSDOT is required to implement 
delay and shutdown measures if a marine mammal is detected to approach 
the exclusion zone. The language is further clarified that after a 
shutdown measure, the construction cannot be resumed until the animal 
is seen leaving the exclusion zone, or 30 minutes have passed since the 
last sight of the animal within the zone. These measures are consistent 
with all authorizations involving in-water pile driving.
    Comment 2: The Commission states that the method NMFS used to 
estimate the numbers of takes during the proposed activities, which 
summed fractions of takes for each species across project days, does 
not account for and negates the intent of NMFS's 24-hour reset policy. 
The Commission states that it noted NMFS developed criteria associated 
with rounding and recommend that NMFS share these with the Commission.
    Response: While for certain projects NMFS has rounded to the whole 
number for daily takes, for projects like

[[Page 50630]]

this one, when the objective of take estimation is to provide more 
accurate assessments of potential impacts to marine mammals for the 
entire project, rounding in the middle of a calculation would introduce 
large errors into the process. In addition, while NMFS uses a 24-hour 
reset for its take calculation to ensure that individual animals are 
not counted as a take more than once per day, that fact does not make 
the calculation and subsequent rounding of take across the entire 
activity period inherently incorrect. There is no need for daily (24-
hour) rounding in this case because there is no daily limit of takes, 
as long as total authorized takes of marine mammal are not exceeded. 
NMFS is working on general guidance for take calculation and will share 
it with the Commission in the near future.

Description of Marine Mammals in the Area of Specified Activities

    We have reviewed the applicants' species information--which 
summarizes available information regarding status and trends, 
distribution and habitat preferences, behavior and life history, and 
auditory capabilities of the potentially affected species--for accuracy 
and completeness and refer the reader to Sections 3 and 4 of the 
applications, as well as to NMFS's Stock Assessment Reports (SAR; 
www.nmfs.noaa.gov/pr/sars/), instead of reprinting all of the 
information here. Additional general information about these species 
(e.g., physical and behavioral descriptions) may be found on NMFS's Web 
site (www.nmfs.noaa.gov/pr/species/mammals/), or in the U.S. Navy's 
Marine Resource Assessments (MRA) for relevant operating areas. The 
MRAs are available online at: www.navfac.navy.mil/products_and_services/ev/products_and_services/marine_resources/marine_resource_assessments.html. Table 2 lists all species with 
expected potential for occurrence in Chehalis Bridge project area and 
summarizes information related to the population or stock, including 
potential biological removal (PBR), where known. For taxonomy, we 
follow Committee on Taxonomy (2016). PBR, 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, is considered in 
concert with known sources of ongoing anthropogenic mortality to assess 
the population-level effects of the anticipated mortality from a 
specific project (as described in NMFS's SARs). While no mortality is 
anticipated or authorized here, PBR and annual serious injury and 
mortality 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 area. NMFS's stock 
abundance estimates for most species represent the total estimate of 
individuals within the geographic area, if known, that comprises that 
stock.
    Five species (with five managed stocks) are considered to have the 
potential to co-occur with the proposed construction activities. All 
values presented in Table 2 are the most recent available at the time 
of publication and are available in the 2015 SARs (Carretta et al., 
2016) and draft 2016 SARs (available online at: www.nmfs.noaa.gov/pr/sars/draft.htm).

                Table 2--Marine Mammals With Potential Presence Within the Proposed Project Area
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                                                                                 Stock
                                                                 ESA/MMPA      abundance
                                                                  status;     (CV, Nmin,               Annual M/
         Common name          Scientific name       Stock        strategic    most recent      PBR       SI \3\
                                                                 (Y/N) \1\     abundance
                                                                              survey) \2\
----------------------------------------------------------------------------------------------------------------
                      Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
----------------------------------------------------------------------------------------------------------------
                                              Family Eschrichtiidae
----------------------------------------------------------------------------------------------------------------
Gray whale..................  Eschrichtius     Eastern North            N           20,990        624        132
                               robustus.        Pacific.
----------------------------------------------------------------------------------------------------------------
                                         Family Phocoenidae (porpoises)
----------------------------------------------------------------------------------------------------------------
Harbor porpoise.............  Phocoena         Washington               N           11,233         66        7.2
                               phocoena.        inland waters.
----------------------------------------------------------------------------------------------------------------
                                     Order Carnivora--Superfamily Pinnipedia
----------------------------------------------------------------------------------------------------------------
                                  Family Otariidae (eared seals and sea lions)
----------------------------------------------------------------------------------------------------------------
California sea lion.........  Zalophus         U.S............          N          296,750      9,200        389
                               californianus.
Steller sea lion............  Eumetopias       Eastern U.S....          N           71,562      2,498        108
                               jubatus.
----------------------------------------------------------------------------------------------------------------
                                         Family Phocidae (earless seals)
----------------------------------------------------------------------------------------------------------------
Harbor seal.................  Phoca vitulina.  Washington               N       \4\ 11,036      1,641         43
                                                northern
                                                inland waters.
----------------------------------------------------------------------------------------------------------------
\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.
\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.
\4\ Harbor seal estimate is based on data that are 8 years old, but this is the best available information for
  use here.


[[Page 50631]]

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    This section includes a summary and discussion of the ways that 
components of the specified activity may impact marine mammals and 
their habitat. The ``Estimated Take by Incidental Harassment'' section 
later in this document will include a quantitative analysis of the 
number of individuals that are expected to be taken by this activity. 
The ``Negligible Impact Analysis and Determination'' section will 
consider the content of this section, the ``Estimated Take by 
Incidental Harassment'' section, and the ``Mitigation'' section, to 
draw conclusions regarding the likely impacts of these activities on 
the reproductive success or survivorship of individuals and how those 
impacts on individuals are likely to impact marine mammal species or 
stocks.
    Potential impacts to marine mammals from the proposed US 101/
Chehalis Bridge repair project are from noise generated during in-water 
pile driving and pile removal activities.

Acoustic Effects

    Here, we first provide background information on marine mammal 
hearing before discussing the potential effects of the use of active 
acoustic sources on marine mammals.
    Marine Mammal Hearing--Hearing is the most important sensory 
modality for marine mammals underwater, and exposure to anthropogenic 
sound can have deleterious effects. To appropriately assess the 
potential effects of exposure to sound, it is necessary to understand 
the frequency ranges marine mammals are able to hear. Current data 
indicate that not all marine mammal species have equal hearing 
capabilities (e.g., Richardson et al., 1995; Wartzok and Ketten, 1999; 
Au and Hastings, 2008). To reflect this, Southall et al. (2007) 
recommended that marine mammals be divided into functional hearing 
groups based on directly measured or estimated hearing ranges on the 
basis of available behavioral response data, audiograms derived using 
auditory evoked potential techniques, anatomical modeling, and other 
data. Note that no direct measurements of hearing ability have been 
successfully completed for mysticetes (i.e., low-frequency cetaceans). 
Subsequently, NMFS (2016) described generalized hearing ranges for 
these marine mammal hearing groups. Generalized hearing ranges were 
chosen based on the approximately 65 decibel (dB) threshold from the 
normalized composite audiograms, with the exception for lower limits 
for low-frequency cetaceans where the lower bound was deemed to be 
biologically implausible and the lower bound from Southall et al. 
(2007) retained. The functional groups and the associated frequencies 
are indicated below (note that these frequency ranges correspond to the 
range for the composite group, with the entire range not necessarily 
reflecting the capabilities of every species within that group):
    <bullet> Low-frequency cetaceans (mysticetes): Generalized hearing 
is estimated to occur between approximately 7 Hertz (Hz) and 35 
kilohertz (kHz), with best hearing estimated to be from 100 Hz to 8 
kHz;
    <bullet> Mid-frequency cetaceans (larger toothed whales, beaked 
whales, and most delphinids): Generalized hearing is estimated to occur 
between approximately 150 Hz and 160 kHz, with best hearing from 10 to 
less than 100 kHz;
    <bullet> High-frequency cetaceans (porpoises, river dolphins, and 
members of the genera Kogia and Cephalorhynchus; including two members 
of the genus Lagenorhynchus, on the basis of recent echolocation data 
and genetic data): Generalized hearing is estimated to occur between 
approximately 275 Hz and 160 kHz.
    <bullet> Pinnipeds in water; Phocidae (true seals): Generalized 
hearing is estimated to occur between approximately 50 Hz to 86 kHz, 
with best hearing between 1-50 kHz;
    <bullet> Pinnipeds in water; Otariidae (eared seals): Generalized 
hearing is estimated to occur between 60 Hz and 39 kHz, with best 
hearing between 2-48 kHz.
    The pinniped functional hearing group was modified from Southall et 
al. (2007) on the basis of data indicating that phocid species have 
consistently demonstrated an extended frequency range of hearing 
compared to otariids, especially in the higher frequency range 
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt, 
2013).
    For more detail concerning these groups and associated frequency 
ranges, please see NMFS (2016) for a review of available information. 
Five marine mammal species (2 cetacean and 3 pinniped (2 otariid and 1 
phocid) species) have the reasonable potential to co-occur with the 
proposed construction activities. Please refer to Table 2. Of the 
cetacean species that may be present, one species is classified as low-
frequency cetaceans (i.e., gray whale), and one is classified as high-
frequency cetaceans (i.e., harbor porpoise).
    The WSDOT's US 101 Chehalis River Bridge Project using in-water 
pile driving and pile removal could adversely affect marine mammal 
species and stocks by exposing them to elevated noise levels in the 
vicinity of the activity area.
    Exposure to high intensity sound for a sufficient duration may 
result in auditory effects such as a noise-induced threshold shift 
(TS)--an increase in the auditory threshold after exposure to noise 
(Finneran et al., 2005). Factors that influence the amount of threshold 
shift include the amplitude, duration, frequency content, temporal 
pattern, and energy distribution of noise exposure. The magnitude of 
hearing threshold shift normally decreases over time following 
cessation of the noise exposure. The amount of TS just after exposure 
is the initial TS. If the TS eventually returns to zero (i.e., the 
threshold returns to the pre-exposure value), it is a temporary 
threshold shift (TTS) (Southall et al., 2007).
    Threshold Shift (noise-induced loss of hearing)--When animals 
exhibit reduced hearing sensitivity (i.e., sounds must be louder for an 
animal to detect them) following exposure to an intense sound or sound 
for long duration, it is referred to as a noise-induced TS. An animal 
can experience TTS) or permanent threshold shift (PTS). TTS can last 
from minutes or hours to days (i.e., there is complete recovery), can 
occur in specific frequency ranges (i.e., an animal might only have a 
temporary loss of hearing sensitivity between the frequencies of 1 and 
10 kHz), and can be of varying amounts (for example, an animal's 
hearing sensitivity might be reduced initially by only 6 dB or reduced 
by 30 dB). PTS is permanent, but some recovery is possible. PTS can 
also occur in a specific frequency range and amount as mentioned above 
for TTS.
    For marine mammals, published data are limited to the captive 
bottlenose dolphin, beluga, harbor porpoise, and Yangtze finless 
porpoise (Finneran et al., 2000, 2002, 2003, 2005, 2007, 2010a, 2010b; 
Finneran and Schlundt, 2010; Lucke et al., 2009; Mooney et al., 2009a, 
2009b; Popov et al., 2011a, 2011b; Kastelein et al., 2012a; Schlundt et 
al., 2000; Nachtigall et al., 2003, 2004). For pinnipeds in water, data 
are limited to measurements of TTS in harbor seals, an elephant seal, 
and California sea lions (Kastak et al., 1999, 2005; Kastelein et al., 
2012b).
    Lucke et al. (2009) found a TS of a harbor porpoise after exposing 
it to airgun noise with a received sound pressure level (SPL) at 200.2 
dB (peak-to-peak) re: 1 micropascal ([mu]Pa), which corresponds to a 
sound exposure level of 164.5 dB re: 1 [mu]Pa\2\ s after integrating

[[Page 50632]]

exposure. Because the airgun noise is a broadband impulse, one cannot 
directly determine the equivalent of root mean square (rms) SPL from 
the reported peak-to-peak SPLs. However, applying a conservative 
conversion factor of 16 dB for broadband signals from seismic surveys 
(McCauley, et al., 2000) to correct for the difference between peak-to-
peak levels reported in Lucke et al. (2009) and rms SPLs, the rms SPL 
for TTS would be approximately 184 dB re: 1 [mu]Pa, and the received 
levels associated with PTS (Level A harassment) would be higher. 
Therefore, based on these studies, NMFS recognizes that TTS of harbor 
porpoises is lower than other cetacean species empirically tested 
(Finneran & Schlundt, 2010; Finneran et al., 2002; Kastelein and 
Jennings, 2012).
    Marine mammal hearing plays a critical role in communication with 
conspecifics, and interpretation of environmental cues for purposes 
such as predator avoidance and prey capture. Depending on the degree 
(elevation of threshold in dB), duration (i.e., recovery time), and 
frequency range of TTS, and the context in which it is experienced, TTS 
can have effects on marine mammals ranging from discountable to serious 
(similar to those discussed in auditory masking, below). For example, a 
marine mammal may be able to readily compensate for a brief, relatively 
small amount of TTS in a non-critical frequency range that occurs 
during a time where ambient noise is lower and there are not as many 
competing sounds present. Alternatively, a larger amount and longer 
duration of TTS sustained during time when communication is critical 
for successful mother/calf interactions could have more serious 
impacts. Also, depending on the degree and frequency range, the effects 
of PTS on an animal could range in severity, although it is considered 
generally more serious because it is a permanent condition. Of note, 
reduced hearing sensitivity as a simple function of aging has been 
observed in marine mammals, as well as humans and other taxa (Southall 
et al., 2007), so one can infer that strategies exist for coping with 
this condition to some degree, though likely not without cost.
    In addition, chronic exposure to excessive, though not high-
intensity, noise could cause masking at particular frequencies for 
marine mammals, which utilize sound for vital biological functions 
(Clark et al., 2009). Acoustic masking is when other noises such as 
from human sources interfere with animal detection of acoustic signals 
such as communication calls, echolocation sounds, and environmental 
sounds important to marine mammals. Therefore, under certain 
circumstances, marine mammals whose acoustical sensors or environment 
are being severely masked could also be impaired from maximizing their 
performance fitness in survival and reproduction.
    Masking occurs at the frequency band that the animals utilize. 
Therefore, since noise generated from vibratory pile driving is mostly 
concentrated at low frequency ranges, it may have less effect on high 
frequency echolocation sounds by odontocetes (toothed whales). However, 
lower frequency man-made noises are more likely to affect detection of 
communication calls and other potentially important natural sounds such 
as surf and prey noise. It may also affect communication signals when 
they occur near the noise band and thus reduce the communication space 
of animals (e.g., Clark et al., 2009) and cause increased stress levels 
(e.g., Foote et al., 2004; Holt et al., 2009).
    Unlike TS, masking, which can occur over large temporal and spatial 
scales, can potentially affect the species at population, community, or 
even ecosystem levels, as well as individual levels. Masking affects 
both senders and receivers of the signals and could have long-term 
chronic effects on marine mammal species and populations. Recent 
science suggests that low frequency ambient sound levels have increased 
by as much as 20 dB (more than three times in terms of sound pressure 
level) in the world's ocean from pre-industrial periods, and most of 
these increases are from distant shipping (Hildebrand, 2009). For 
WSDOT's Chehalis Bridge repair activities, noises from vibratory pile 
driving and pile removal contribute to the elevated ambient noise 
levels in the project area, thus increasing potential for or severity 
of masking. Baseline ambient noise levels in the vicinity of project 
area are high due to ongoing shipping, construction and other 
activities in the Puget Sound.
    Finally, marine mammals' exposure to certain sounds could lead to 
behavioral disturbance (Richardson et al., 1995), such as: Changing 
durations of surfacing and dives, number of blows per surfacing, or 
moving direction and/or speed; reduced/increased vocal activities; 
changing/cessation of certain behavioral activities (such as 
socializing or feeding); visible startle response or aggressive 
behavior (such as tail/fluke slapping or jaw clapping); avoidance of 
areas where noise sources are located; and/or flight responses (e.g., 
pinnipeds flushing into water from haulouts or rookeries).
    The onset of behavioral disturbance from anthropogenic noise 
depends on both external factors (characteristics of noise sources and 
their paths) and the receiving animals (hearing, motivation, 
experience, demography) and is also difficult to predict (Southall et 
al., 2007). Currently NMFS uses a received level of 160 dB re 1 [mu]Pa 
(rms) to predict the onset of behavioral harassment from impulse noises 
(such as impact pile driving), and 120 dB re 1 [mu]Pa (rms) for 
continuous noises (such as vibratory pile driving). For the WSDOT's US 
101 Chehalis River Bridge Project, only the 120-dB level is considered 
for effects analysis because WSDOT plans to use vibratory pile driving 
and pile removal.
    The biological significance of many of these behavioral 
disturbances is difficult to predict, especially if the detected 
disturbances appear minor. However, the consequences of behavioral 
modification could be biologically significant if the change affects 
growth, survival, and/or reproduction, which depends on the severity, 
duration, and context of the effects.

Potential Effects on Marine Mammal Habitat

    The primary potential impacts to marine mammal habitat are 
associated with elevated sound levels produced by vibratory pile 
removal and pile driving in the area. However, other potential impacts 
to the surrounding habitat from physical disturbance are also possible.
    With regard to fish as a prey source for cetaceans and pinnipeds, 
fish are known to hear and react to sounds and to use sound to 
communicate (Tavolga et al., 1981) and possibly avoid predators (Wilson 
and Dill, 2002). Experiments have shown that fish can sense both the 
strength and direction of sound (Hawkins, 1981). Primary factors 
determining whether a fish can sense a sound signal, and potentially 
react to it, are the frequency of the signal and the strength of the 
signal in relation to the natural background noise level.
    The level of sound at which a fish will react or alter its behavior 
is usually well above the detection level. Fish have been found to 
react to sounds when the sound level increased to about 20 dB above the 
detection level of 120 dB (Ona, 1988); however, the response threshold 
can depend on the time of year and the fish's physiological condition 
(Engas et al., 1993). In general, fish react more strongly to pulses of 
sound (such as noise from impact pile driving) rather than continuous 
signals (such as noise from vibratory pile driving) (Blaxter et al., 
1981), and a quicker alarm response is elicited when the sound signal 
intensity

[[Page 50633]]

rises rapidly compared to sound rising more slowly to the same level.
    During the coastal construction only a small fraction of the 
available habitat would be ensonified at any given time. Disturbance to 
fish species would be short-term and fish would return to their pre-
disturbance behavior once the pile driving activity ceases. Thus, the 
proposed construction would have little, if any, impact on marine 
mammals' prey availability in the area where construction work is 
planned.
    Finally, the time of the proposed construction activity would avoid 
the spawning season of the ESA-listed salmonid species.

Estimated Take

    This section provides an estimate of the number of incidental takes 
authorized through this IHA, which will inform 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 would be by Level B harassment only, in the form 
of disruption of behavioral patterns for individual marine mammals 
resulting from exposure to noise generated from vibratory pile driving 
and removal. Based on the nature of the activity and the anticipated 
effectiveness of the mitigation measures (i.e., shutdown measures--
discussed in detail below in Mitigation section), Level A harassment is 
neither anticipated nor authorized.
    As described previously, no mortality is anticipated or 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 take estimate.

Acoustic Thresholds

    Using the best available science, NMFS has developed acoustic 
thresholds that identify the received level of underwater sound above 
which exposed marine mammals would be reasonably expected to be 
behaviorally harassed (equated to Level B harassment) or to incur PTS 
of some degree (equated to Level A harassment).
    Level B Harassment for non-explosive sources--Though significantly 
driven by received level, the onset of behavioral disturbance from 
anthropogenic noise exposure is also informed to varying degrees by 
other factors related to the source (e.g., frequency, predictability, 
duty cycle), the environment (e.g., bathymetry), and the receiving 
animals (hearing, motivation, experience, demography, behavioral 
context) and can be difficult to predict (Southall et al., 2007, 
Ellison et al., 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 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.
    Applicant's proposed activity includes the use of continuous 
(vibratory pile driving and removal) source, and therefore the 120 dB 
re 1 [mu]Pa (rms) is 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). 
Applicant's proposed activity includes the use non-impulsive (vibratory 
pile driving and pile removal) source.
    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 the table 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: http://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm.

                 Table 3--Current Acoustic Exposure Criteria for Non-Explosive Sound Underwater
----------------------------------------------------------------------------------------------------------------
                                            PTS onset thresholds                    Behavioral thresholds
         Hearing group          --------------------------------------------------------------------------------
                                        Impulsive          Non-impulsive        Impulsive        Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans...  Lpk,flat: 219           LE,LF,24h: 199 dB  Lrms,flat: 160 dB  Lrms,flat: 120
                                  dB,LE,LF,24h: 183 dB.                                         dB.
Mid-Frequency (MF) Cetaceans...  Lpk,flat: 230           LE,MF,24h: 198 dB
                                  dB,LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans..  Lpk,flat: 202           LE,HF,24h: 173 dB
                                  dB,LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW)            Lpk,flat: 218           LE,PW,24h: 201 dB
 (Underwater).                    dB,LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW)           Lpk,flat: 232           LE,OW,24h: 219 dB
 (Underwater).                    dB,LE,OW,24h: 203 dB.
----------------------------------------------------------------------------------------------------------------
* 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.

[[Page 50634]]

 
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.

Source Levels

    The project includes vibratory pile driving and removal of steel H 
piles and sheet piles. The dimension of the H piles is unknown, but not 
is expected to be more than 12 inches (in).
    Source levels for the steel H pile vibratory driving are based on 
in-water measurements reported by CALTRANS (2015) of 12-in steel H 
pile, which are 150 dB<INF>rms</INF> and 165 dB<INF>peak</INF> re 1 
[micro]Pa at 10 meters (m). Source levels for the sheet pile are based 
on in-water measurements at the Elliot Bay Seawall Project (The 
Greenbush Group, 2015), which is 165 dB<INF>rms</INF> and 180 
dB<INF>peak</INF> re 1 [micro]Pa at 10 m. For vibratory pile removal, 
the source levels are conservatively estimated using the pile driving 
source levels as proxies.
    A summary of source levels from different pile driving and pile 
removal activities is provided in Table 4.

                             Table 4--Summary of In-Water Pile Driving Source Levels
                                              [At 10 m from source]
----------------------------------------------------------------------------------------------------------------
                                                                               SEL (dB re 1     SPLrms (dB re 1
                   Method                            Pile type/size          [micro]Pa \2\-s)      [micro]Pa)
----------------------------------------------------------------------------------------------------------------
Vibratory driving/removal..................  12-in steel H pile...........                150                150
Vibratory driving/removal..................  Sheet pile...................                165                165
----------------------------------------------------------------------------------------------------------------

    These source levels are used to compute the Level A injury zones 
and to estimate the Level B harassment zones. For Level A harassment 
zones, since the peak source levels for both pile driving are below the 
injury thresholds, cumulative SEL were used to do the calculations 
using the NMFS acoustic guidance (NMFS 2016).

Estimating Injury Zones

    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 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 cumulative SEL (L<INF>E</INF>), distances to marine mammal 
injury thresholds were estimated using NMFS Optional User Spreadsheet 
based on the noise exposure guidance.
    Isopleths to Level B behavioral zones are based on rms SPL 
(SPL<INF>rms</INF>) that are specific for non-impulse (vibratory pile 
driving) sources. Distances to marine mammal behavior thresholds were 
calculated using practical spreading.
    A summary of the measured and modeled harassment zones is provided 
in Table 5.

                                     Table 5--Distances to Harassment Zones
----------------------------------------------------------------------------------------------------------------
                                                                   Injury zone (m)
                                               -------------------------------------------------------  Behavior
    Pile type, size and pile driving method         LF         MF         HF                            zone (m)
                                                 cetacean   cetacean   cetacean    Phocid    Otariid
----------------------------------------------------------------------------------------------------------------
Vibratory driving & removal, sheet pile, 10          36.9        3.3       54.6       22.4        1.6     10,000
 piles/day....................................
Vibratory driving & removal, steel H pile, 6          2.6        0.2        3.9        1.6        0.1      1,000
 piles/day....................................
----------------------------------------------------------------------------------------------------------------

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 most cases, marine mammal density data are from the U.S. Navy 
Marine Species Density Database (U.S. Navy 2015). Harbor seal density 
is based on a counts of harbor seals at 44 low-tide haul outs in Grays 
Harbor by Jeffries, et al. (2000), the estimated density of harbor 
seals in the US 101 Chehalis River Bridge project area is 29.4 animals 
per square kilometer (km\2\).
    The Navy Marine Species Density Database (U.S. Navy 2015) estimates 
the density of California sea lions in the waters offshore of Grays 
Harbor as 0.033 animals/km\2\. This estimate will be used as a 
surrogate for Grays Harbor.
    The Navy Marine Species Density Database (U.S. Navy 2015) estimates 
the density of Steller sea lions in the waters offshore of Grays Harbor 
as 0.0145 animals/km\2\. This estimate will be used as a surrogate for 
Grays Harbor.
    The Navy Marine Species Density Database (U.S. Navy 2015) estimates 
the density of harbor porpoises in the waters offshore of Grays Harbor 
as a range between 0.69 and 1.67 animals

[[Page 50635]]

per square kilometer. According to Evenson, et al. (2016), the maximum 
harbor porpoise density in the Strait of Juan de Fuca (approximately 
105 miles north of Grays Harbor) in 2014 was 0.768 animals/km\2\. The 
higher density estimate for waters offshore of Grays Harbor (1.67) will 
be used for this analysis.
    According to counts conducted by Calambokidis et al. (2012), 29 
gray whales were observed over a 12-year period during the months of 
July through September (the proposed period of project activities). 
Based on this data, an average of 2.25 gray whales may be present in 
Grays Harbor/south Washington coast during the 3-month period.

Take Calculation and Estimation

    Here we describe how the information provided above is brought 
together to produce a quantitative take estimate. For all marine mammal 
species except gray whale, estimated takes are calculated based on 
ensonified area for a specific pile driving activity multiplied by the 
marine mammal density in the action area, multiplied by the number of 
pile driving (or removal) days. Distances to and areas of different 
harassment zones are listed in Tables 5 and 6. Total days for sheet 
pile driving and removal are five days each, and the total day for 
steel H pile driving and removal is one day each.

                                       Table 6--Areas of Harassment Zones
----------------------------------------------------------------------------------------------------------------
                                                                 Injury zone (km\2\)
                                               -------------------------------------------------------  Behavior
    Pile type, size and pile driving method         LF         MF         HF                              zone
                                                 cetacean   cetacean   cetacean    Phocid    Otariid    (km\2\)
----------------------------------------------------------------------------------------------------------------
Vibratory driving & removal, sheet pile, 10         0.004      0.000      0.009      0.002      0.000       2.13
 piles/day....................................
Vibratory driving & removal, steel H pile, 6        0.000      0.000      0.000      0.000      0.000       0.67
 piles/day....................................
----------------------------------------------------------------------------------------------------------------

    The results predicted that a total of 666 harbor seals, 1 
California sea lion, 0 Steller sea lion, and 38 harbor porpoise could 
be exposure to received levels that would cause Level B harassment. 
However, owing to the prior observations that California sea lion and 
Steller sea lion's presence in the project area, we adjusted the take 
number of these species to 10.
    For gray whales, the Level B takes were estimate based on an 
average sighting of 2.25 whales in Grays Harbor/south Washington Coast 
during the months of July through September (Calambokidis et al., 
(2012) adjusted upwards to 3 animals.
    Due to the extreme small injury zones (maximum zone is 0.009 km\2\ 
for high-frequency cetacean), the calculation predicted no animals 
would be exposed to noise levels that could cause Level A harassment, 
and therefore no Level A take is authorized. A summary of estimated 
marine mammal Level B takes is listed in Table 7.

  Table 7--Estimated Numbers of Marine Mammals That May Be Exposed to Received Noise Levels That Cause Level B
                                                   Harassment
----------------------------------------------------------------------------------------------------------------
                                                      Density
                     Species                         (animals/       Estimated       Abundance      Percentage
                                                      km\2\)       Level B take
----------------------------------------------------------------------------------------------------------------
Pacific harbor seal.............................            29.4             666          11,036            6.03
California sea lion.............................           0.033              10         296,750            0.00
Steller sea lion................................          0.0145              10          71,562            0.00
Gray whale......................................              NA               3          20,990            0.00
Harbor porpoise.................................            1.67              38          11,233            0.34
----------------------------------------------------------------------------------------------------------------

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

1. Time Restriction
    Work would occur only during daylight hours, when visual monitoring 
of marine mammals can be conducted. In addition, all in-water 
construction will be limited to the period between July 16, 2018, and 
September 30, 2018.

[[Page 50636]]

2. Establishing and Monitoring Level A, Level B Harassment Zones, and 
Exclusion Zones
    Before the commencement of in-water construction activities, which 
include vibratory pile driving and pile removal, WSDOT shall establish 
Level A harassment zones where received underwater SEL<INF>cum</INF> 
could cause PTS (see above).
    WSDOT shall also establish Level B harassment zones where received 
underwater SPLs are higher than 120 dB<INF>rms</INF> re 1 [mu]Pa for 
non-impulsive noise sources (vibratory pile driving and pile removal).
    WSDOT shall establish exclusion zones within which marine mammals 
could be taken by Level A harassment. For Level A harassment zones that 
is less than 10 m from the source, a minimum of 10 m distance should be 
established as an exclusion zone.
    A summary of exclusion zones is provided in Table 8.

          Table 8--Exclusion Zones for Various Pile Driving Activities and Marine Mammal Hearing Groups
----------------------------------------------------------------------------------------------------------------
                                                                Exclusion zone (m)
Pile type, size and pile driving -------------------------------------------------------------------------------
             method                 LF cetacean     MF cetacean     HF cetacean       Phocid          Otariid
----------------------------------------------------------------------------------------------------------------
Vibratory driving and removal,                37              10              55              22              10
 sheet pile, 10 piles/day.......
Vibratory driving & removal,                  10              10              10              10              10
 steel H pile, 6 piles/day......
----------------------------------------------------------------------------------------------------------------

    NMFS-approved protected species observers (PSO) shall conduct an 
initial survey of the exclusion zones to ensure that no marine mammals 
are seen within the Level A zones before pile driving and pile removal 
of a pile segment begins. If marine mammals are found within the 
exclusion zone, pile driving of the segment would be delayed until they 
move out of the area. If a marine mammal is seen above water and then 
dives below, the contractor would wait 30 minutes. If no marine mammals 
are seen by the observer in that time it can be assumed that the animal 
has moved beyond the exclusion zone.
    If pile driving of a segment ceases for 30 minutes or more and a 
marine mammal is sighted within the designated exclusion zone prior to 
commencement of pile driving, the observer(s) must notify the pile 
driving operator (or other authorized individual) immediately and 
continue to monitor the exclusion zone. Operations may not resume until 
the marine mammal has exited the exclusion zone or 30 minutes have 
elapsed since the last sighting.
3. Shutdown Measures
    WSDOT shall implement shutdown measures if a marine mammal is 
detected within an exclusion zone or is about to enter an exclusion 
zone listed in Table 8. In-water pile driving may not resume until the 
animal is seen leaving the exclusion zone, or 30 minutes have passed 
since the sighting of the animal within the exclusion zone.
    Further, WSDOT shall implement shutdown measures if the number of 
authorized takes for any particular species reaches the limit under the 
IHA (if issued) and if such marine mammals are sighted within the 
vicinity of the project area and are approaching the Level B harassment 
zone during in-water construction activities.
    Based on our evaluation of the required measures, NMFS has 
determined that the prescribed 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 
proposed 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:
    <bullet> Occurrence of marine mammal species or stocks in the area 
in which take is anticipated (e.g., presence, abundance, distribution, 
density);
    <bullet> 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);
    <bullet> Individual marine mammal responses (behavioral or 
physiological) to acoustic stressors (acute, chronic, or cumulative), 
other stressors, or cumulative impacts from multiple stressors;
    <bullet> How anticipated responses to stressors impact either: (1) 
Long-term fitness and survival of individual marine mammals; or (2) 
populations, species, or stocks;
    <bullet> Effects on marine mammal habitat (e.g., marine mammal prey 
species, acoustic habitat, or other important physical components of 
marine mammal habitat); and
    <bullet> Mitigation and monitoring effectiveness.

Monitoring Measures

    WSDOT shall employ NMFS-approved PSOs to conduct marine mammal 
monitoring for its U.S. 101/Chehalis Bridge Repair Project. The 
purposes of marine mammal monitoring are to implement mitigation 
measures and learn more about impacts to marine mammals from WSDOT's 
construction activities. The PSOs will observe and collect data on 
marine mammals in and around the project area for 30 minutes before, 
during, and for 30 minutes after all pile removal and pile installation 
work. NMFS-approved PSOs shall meet the following requirements:
    1. Independent observers (i.e., not construction personnel) are 
required;
    2. At least one observer must have prior experience working as an 
observer;
    3. Other observers may substitute education (undergraduate degree 
in biological science or related field) or training for experience;
    4. Where a team of three or more observers are required, one 
observer

[[Page 50637]]

should be designated as lead observer or monitoring coordinator. The 
lead observer must have prior experience working as an observer; and
    5. NMFS will require submission and approval of observer CVs.
    Monitoring of marine mammals around the construction site shall be 
conducted using high-quality binoculars (e.g., Zeiss, 10 x 42 power). 
Due to the different sizes of ZOIs from different pile types, two 
different ZOIs and different monitoring protocols corresponding to a 
specific pile type will be established.
    <bullet> For vibratory pile driving and pile removal of sheet 
piles, a total of four land-based PSOs will monitor the exclusion zones 
and Level B harassment zone.
    <bullet> For vibratory pile driving and pile removal of H piles, a 
total of three land-based PSOs will monitor the exclusion zones and 
Level B harassment zone.
    Locations of the land-based PSOs and routes of monitoring vessels 
are shown in WSDOT's Marine Mammal Monitoring Plan, which is available 
online at www.nmfs.noaa.gov/pr/permits/incidental/construction.htm.
    To verify the required monitoring distance, the exclusion zones and 
ZOIs will be determined by using a range finder or hand-held global 
positioning system device.

Reporting Measures

    WSDOT is required to submit a draft monitoring report within 90 
days after completion of the construction work or the expiration of the 
IHA, whichever comes earlier. This report would detail the monitoring 
protocol, summarize the data recorded during monitoring, and estimate 
the number of marine mammals that may have been harassed. NMFS would 
have an opportunity to provide comments on the report, and if NMFS has 
comments, WSDOT would address the comments and submit a final report to 
NMFS within 30 days.
    In addition, NMFS would require WSDOT to notify NMFS' Office of 
Protected Resources and NMFS' West Coast Stranding Coordinator within 
48 hours of sighting an injured or dead marine mammal in the 
construction site. WSDOT shall provide NMFS and the Stranding Network 
with the species or description of the animal(s), the condition of the 
animal(s) (including carcass condition, if the animal is dead), 
location, time of first discovery, observed behaviors (if alive), and 
photo or video.
    In the event that WSDOT finds an injured or dead marine mammal that 
is not in the construction area, WSDOT would report the same 
information as listed above to NMFS as soon as operationally feasible.

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, this introductory discussion of our analyses 
applies to all the species listed in Table 7, given that the 
anticipated effects of WSDOT's Chehalis Bridge repair project 
activities involving pile driving and pile removal on marine mammals 
are expected to be relatively similar in nature. There is no 
information about the nature or severity of the impacts, or the size, 
status, or structure of any species or stock that would lead to a 
different analysis by species for this activity, or else species-
specific factors would be identified and analyzed.
    For all marine mammal species, takes that are anticipated and 
authorized are expected to be limited to short-term Level B harassment 
(behavioral) because of the small scale (only a total of 100 piles to 
be installed and removed), lower source levels (small piles by 
vibratory pile driving and pile removal), and short durations (maximum 
five hours pile driving or pile removal per day). Marine mammals 
present in the vicinity of the action area and taken by Level B 
harassment would most likely show overt brief disturbance (startle 
reaction) and avoidance of the area from elevated noise levels during 
pile driving and pile removal. For these reasons, these behavioral 
impacts are not expected to affect marine mammals' growth, survival, 
and reproduction, especially considering the limited geographic area 
that would be affected in comparison to the much larger habitat for 
marine mammals in the Pacific Northwest.
    The project also is not expected to have significant adverse 
effects on affected marine mammals' habitat, as analyzed in detail in 
the ``Anticipated Effects on Marine Mammal Habitat'' section. There is 
no ESA designated critical area in the vicinity of the Chehalis Bridge 
Project area. The project activities would not permanently modify 
existing marine mammal habitat. The activities may kill some fish and 
cause other fish to leave the area temporarily, thus impacting marine 
mammals' foraging opportunities in a limited portion of the foraging 
range; but, because of the short duration of the activities and the 
relatively small area of the habitat that may be affected, the impacts 
to marine mammal habitat are not expected to cause significant or long-
term negative consequences. Therefore, given the consideration of 
potential impacts to marine mammal prey species and their physical 
environment, WSDOT's proposed construction activity at Chehalis Bridge 
would not adversely affect marine mammal habitat.
    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:
    <bullet> No injury, series injury, or mortality is anticipated or 
authorized;
    <bullet> All harassment is Level B harassment in the form of short-
term behavioral modification; and
    <bullet> No areas of specific importance to affected species are 
impacted.
    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 prescribed monitoring and 
mitigation measures, NMFS finds that the total take from the proposed 
activity will have a negligible impact on all affected marine mammal 
species or stocks.

[[Page 50638]]

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, 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.
    The estimated takes are below seven percent of the population for 
all marine mammals (Table 7).
    Based on the analysis contained herein of the proposed activity 
(including the prescribed 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 Subsistence 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)

    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

    As a result of these determinations, NMFS has issued an IHA to the 
Washington State Department of Transportation for the U.S. 101/Chehalis 
River Bridge--Scour Repair in Washington State, provided the previously 
described mitigation, monitoring, and reporting requirements are 
incorporated.

    Dated: October 26, 2017.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2017-23748 Filed 10-31-17; 8:45 am]
 BILLING CODE 3510-22-P