[Federal Register Volume 87, Number 73 (Friday, April 15, 2022)]
[Notices]
[Pages 22506-22520]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-08135]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XB891]


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to BNSF Railway Bridge Heavy 
Maintenance Project in King County, Washington

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

ACTION: Notice; issuance of two incidental harassment authorizations.

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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 two consecutive IHAs to the BNSF Railway (BNSF) to 
incidentally harass, by Level a and Level B harassment, marine mammals 
over 2 years during construction associated with the Railway Bridge 
Heavy Maintenance Project in King County, Washington.

DATES: The Year 1 Authorization is effective from July 16, 2022 to July 
15, 2023. The Year 2 Authorization is effective from July 16, 2023 to 
July 15, 2024.

FOR FURTHER INFORMATION CONTACT: Robert Pauline, Office of Protected 
Resources, NMFS, (301) 427-8401. Electronic copies of the application 
and supporting documents, as well as a list of the references cited in 
this document, may be obtained online at: https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act. In case of problems accessing these 
documents, please call the contact listed above.

[[Page 22507]]


SUPPLEMENTARY INFORMATION:

Background

    The MMPA prohibits the ``take'' of marine mammals, with certain 
exceptions. sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to 
allow, upon request, the incidental, but not intentional, taking of 
small numbers of marine mammals by U.S. citizens who engage in a 
specified activity (other than commercial fishing) within a specified 
geographical region if certain findings are made and either regulations 
are proposed or, if the taking is limited to harassment, a notice of a 
proposed incidental harassment authorization is provided to the public 
for review.
    Authorization for incidental takings shall be granted if NMFS finds 
that the taking will have a negligible impact on the species or 
stock(s) and will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for taking for subsistence uses 
(where relevant). Further, NMFS must prescribe the permissible methods 
of taking and other ``means of effecting the least practicable adverse 
impact'' on the affected species or stocks and their habitat, paying 
particular attention to rookeries, mating grounds, and areas of similar 
significance, and on the availability of the species or stocks for 
taking for certain subsistence uses (referred to in shorthand as 
``mitigation''); and requirements pertaining to the mitigation, 
monitoring and reporting of the takings are set forth.

Summary of Request

    On August 17, 2021, NMFS received a request from BNSF Railway 
(BNSF) for two consecutive IHAs allowing the take of marine mammals 
incidental to construction associated with the Railway Bridge 0050-
0006.3 (Bridge 6.3) Heavy Maintenance Project in King County, 
Washington. The application was deemed adequate and complete on 
November 22, 2021. BNSF's request is for take of a small number of 
seven species of marine mammal by Level B harassment and Level A 
harassment. Neither BNSF nor NMFS expects serious injury or mortality 
to result from this activity and, therefore, IHAs are appropriate.

Description of Planned Activity

Overview

    The purpose of this project is to extend the service life of the 
existing structure by replacing several components of the existing 
movable span including replacing the existing counterweight, 
counterweight trunnion bearings, and rocker frame system of the 
existing movable span. This work would occur over 2 years, requiring 
the issuance of two consecutive IHAs. BNSF is planning to engage in 
maintenance activities at Bridge 6.3, a bridge with a movable deck to 
allow vessels to pass. In-water activities that could result in take of 
marine mammals include impact pile driving of 36-inch temporary steel 
piles (which will be removed via cutting with Broco Rod which is not 
likely to cause take), vibratory installation and extraction of 14-inch 
H-piles, vibratory installation and extraction of 12-inch timber piles, 
hydraulic clipper cutting and extraction of 12-inch timber piles, 
drilling of 48-inch diameter shafts using oscillator rotator equipment, 
and removing the pile created by filling the drilled shaft and steel 
casing with concrete and removing the casing with a diamond wire saw. 
BSNF estimates that the project will requires approximately 122 days of 
in-water work over 24 months. The IHAs would be effective from July 16, 
2022 to July 15, 2023 for Year 1, which would include 113 days of in-
water activities and July 16, 2023 to July 15, 2024 for Year 2, which 
would include 9 days of in-water activities. Table 1 provides a summary 
of the pile driving activities.
    A detailed description of the planned testing activities is 
provided in the Federal Register notice of the proposed IHAs (87 FR 
4844; January 31, 2022). Since that time, no changes have been made to 
the project activities. Therefore, a detailed description is not 
provided here. Please refer to that Federal Register notice for the 
description of the specified activities.

                     Table 1--Summary of Pile Driving Activities and User Spreadsheet Inputs
----------------------------------------------------------------------------------------------------------------
                                                                                     Minutes/        Length of
        Pile size              Pile type         Construction      Piles/shafts     strikes per      activity
                                                    method            per day          pile           (days)
----------------------------------------------------------------------------------------------------------------
36 inch.................  Steel pipe........  Impact............               6           1,000              20
14 inch.................  H-pile............  Vibratory.........               8              30               6
12 inch.................  Timber Pile.......  Vibratory.........              10              15               8
12 inch.................  Timber Pile.......  Hydraulic Pile                  20               4               4
                                               Clipper.
48-inch.................  Steel Shaft.......  Oscillator........            0.25           1,920              88
48-inch.................  Steel-encased       Diamond bladed                   4              60               6
                           Concrete Shaft.     wire saw.
----------------------------------------------------------------------------------------------------------------

Comments and Responses

    A notice of NMFS's proposal to issue IHAs to DAF was published in 
the Federal Register on January 31, 2022 (87 FR 4844). That proposed 
notice described, in detail, BNSF's activities, the marine mammal 
species that may be affected by the activities and the anticipated 
effects on marine mammals. During the 30-day public comment period, 
NMFS received no public comments or comments from the Marine Mammal 
Commission.

Changes From the Proposed IHAs to Final IHAs

    No changes have been made from the notice of proposed IHAs.

Description of Marine Mammals in the Area of Specified Activities

    Sections 3 and 4 of the application summarize available information 
regarding status and trends, distribution and habitat preferences, and 
behavior and life history, of the potentially affected species. 
Additional information regarding population trends and threats may be 
found in NMFS's Stock Assessment Reports (SARs; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and more general information about these species 
(e.g., physical and behavioral descriptions) may be found on NMFS's 
website (https://www.fisheries.noaa.gov/find-species).
    Table 2 lists all species or stocks for which take is expected and 
authorized for this action, and summarizes information related to the 
population or stock, including regulatory status under the MMPA and 
Endangered Species Act (ESA) and potential biological removal (PBR), 
where known. For taxonomy, we follow Committee on Taxonomy (2021).

[[Page 22508]]

PBR is defined by the MMPA as the maximum number of animals, not 
including natural mortalities, that may be removed from a marine mammal 
stock while allowing that stock to reach or maintain its optimum 
sustainable population (as described in NMFS's SARs). While no 
mortality is anticipated or authorized here, PBR and annual serious 
injury and mortality from anthropogenic sources are included here as 
gross indicators of the status of the species and other threats.
    Marine mammal abundance estimates presented in this document 
represent the total number of individuals that make up a given stock or 
the total number estimated within a particular study or survey area. 
NMFS's stock abundance estimates for most species represent the total 
estimate of individuals within the geographic area, if known, that 
comprises that stock. For some species, this geographic area may extend 
beyond U.S. waters. All managed stocks in this region are assessed in 
NMFS's U.S. SARs (e.g., Carretta et al., 2021a). All values presented 
in Table 2 are the most recent available at the time of publication and 
are available in the 2020 U.S. Pacific SARs (Carretta et al., 2021a) 
and 2021 draft Pacific and Alaska SARs (Carretta et al., 2021b, Muto et 
al., 2021) available online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports.

                                                          Table 2--Species Authorized for Take
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                         ESA/MMPA status;    Stock abundance  (CV,
             Common name                  Scientific name               Stock             strategic (Y/N)      Nmin, most recent       PBR     Annual M/
                                                                                                \a\          abundance survey) \b\               SI \c\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                            Order Cetartiodactyla--Cetacea--Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Balaenopteridae (rorquals):
    Minke whale.....................  Balaenoptera             California/Oregon/       -, -, N             915 (0.792, 509, 2018)        4.1     >=0.59
                                       acutorostrata.           Washington.
Family Delphinidae:
    Common Bottlenose Dolphin.......  Tursiops truncatus.....  California/Oregon/       -, -, N             3,477 (0.696, 2,048,        19.70       0.82
                                                                Washington offshore.                         2018).
    Long-beaked Common Dolphin......  Delphinus capensis.....  California.............  -, -, N             83,379 (0.216, 69,636,        668     >=29.7
                                                                                                             2018).
Family Phocoenidae (porpoises):
    Harbor porpoise.................  Phocoena phocoena......  Washington Inland        -, -, N             11,233 (0.37, 8,308,           66      >=7.2
                                                                Waters.                                      2015).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals and
 sea lions):
    California Sea Lion.............  Zalophus californianus.  United States..........  -, -, N             257,606 (N/A, 233,515,     14,011       >320
                                                                                                             2014).
    Steller sea lion................  Eumetopias jubatus       Eastern U.S............  -, -, N             43,201 \e\ (see SAR,        2,592        113
                                       monteriensis.                                                         43,201, 2017).
Family Phocidae (earless seals):
    Harbor seal.....................  Phoca vitulina.........  Washington Northern      -, -, N             1,088 (0.15, UNK,              NA       10.6
                                                                Inland Waters.                               1999) \f\.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ 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.
\b\ NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance.
\c\ 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 mortality/serious injury (M/SI) often cannot be determined precisely and is in some cases presented as a
  minimum value or range.
\d\ Based on counts of individual animals identified from photo-identification catalogues. Surveys for abundance estimates of these stocks are conducted
  infrequently.
\e\ Best estimate of pup and non-pup counts, which have not been corrected to account for animals at sea during abundance surveys.
\f\ The abundance estimate for this stock is greater than eight years old and is therefore not considered current. PBR is considered undetermined for
  this stock, as there is no current minimum abundance estimate for use in calculation. We nevertheless present the most recent abundance estimates, as
  these represent the best available information for use in this document.

    A detailed description of the species likely to be affected by 
BNSF's activities, including brief information regarding population 
trends and threats, and information regarding local occurrence, were 
provided in the Federal Register notice for the proposed IHA (87 FR 
4844; January 31, 2022). Since that time, we are not aware of any 
changes in the status of these species and stocks; therefore, detailed 
descriptions are not provided here. Please refer to that Federal 
Register notice for those descriptions. Please also refer to NMFS's 
website (https://www.fisheries.noaa.gov/find-species) for generalized 
species accounts.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    The effects of testing activities have the potential to result in 
behavioral harassment of marine mammals in the vicinity of the study 
area. The Federal Register notice for the proposed IHAs (87 FR 4844; 
January 31, 2022) included a discussion of the effects of anthropogenic 
noise on marine mammals and their habitat, therefore that information 
is not repeated here; please refer to the Federal Register notice (87 
FR 4844; January 31, 2022) for that information.

Estimated Take

    This section provides an estimate of the number of incidental takes 
authorized through this IHA, which will inform both NMFS' consideration 
of ``small numbers'' and the negligible impact determination.
    Harassment is the only type of take expected to result from these 
activities. Except with respect to certain activities not pertinent 
here, section 3(18) of the MMPA defines ``harassment'' as any act of 
pursuit, torment, or annoyance, which (i) has the potential to injure a 
marine mammal or marine mammal stock in the wild (Level A harassment);

[[Page 22509]]

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 primarily be by Level B harassment, as use 
of the acoustic sources for pile installation and extraction has the 
potential to result in disruption of behavioral patterns for individual 
marine mammals. There is also some potential for auditory injury (Level 
A harassment) to result, primarily for harbor seals, because predicted 
auditory injury zones are large. Auditory injury is unlikely to occur 
for low-frequency cetaceans, mid-frequency cetaceans, high-frequency 
cetaceans, and otariids. The planned mitigation and monitoring measures 
are expected to minimize the severity of the taking to the extent 
practicable.
    As described previously, no mortality is anticipated or authorized 
for this activity. Below we describe how the take is estimated.
    Generally speaking, we estimate take by considering: (1) Acoustic 
thresholds above which NMFS believes the best available science 
indicates marine mammals will be behaviorally harassed or incur some 
degree of permanent hearing impairment; (2) the area or volume of water 
that will be ensonified above these levels in a day; (3) the density or 
occurrence of marine mammals within these ensonified areas; and, (4) 
the number of days of activities. We note that while these basic 
factors can contribute to a basic calculation to provide an initial 
prediction of takes, additional information that can qualitatively 
inform take estimates is also sometimes available (e.g., previous 
monitoring results or average group size). Below, we describe the 
factors considered here in more detail and present the authorized take 
estimate.

Acoustic Thresholds

    NMFS recommends the use of acoustic thresholds that identify the 
received level of underwater sound above which exposed marine mammals 
would be reasonably expected to be behaviorally harassed (equated to 
Level B harassment) or to incur PTS of some degree (equated to Level A 
harassment).
    Level B Harassment for non-explosive sources--Though significantly 
driven by received level, the onset of behavioral disturbance from 
anthropogenic noise exposure is also informed to varying degrees by 
other factors related to the source (e.g., frequency, predictability, 
duty cycle), the environment (e.g., bathymetry), and the receiving 
animals (hearing, motivation, experience, demography, behavioral 
context) and can be difficult to predict (Southall et al., 2007, 
Ellison et al., 2012). Based on what the available science indicates 
and the practical need to use a threshold based on a factor that is 
both predictable and measurable for most activities, NMFS uses a 
generalized acoustic threshold based on received level to estimate the 
onset of behavioral harassment. NMFS predicts that marine mammals are 
likely to be behaviorally harassed in a manner we consider Level B 
harassment when exposed to underwater anthropogenic noise above 
received levels of 120 dB re 1 [mu]Pa (rms) for continuous (e.g., 
vibratory pile-driving, drilling) and above 160 dB re 1 [mu]Pa (rms) 
for non-explosive impulsive (e.g., seismic airguns) or intermittent 
(e.g., scientific sonar) sources.
    BNSF's planned activity includes the use of continuous (vibratory 
pile driving and removal, oscillator rotator equipment, wire saw 
cutting, clipping) and impulsive (impact pile driving) equipment, and 
therefore both the 120- and 160-dB re 1 [mu]Pa (rms) thresholds are 
applicable.
    Level A harassment for non-explosive sources--NMFS' Technical 
Guidance for Assessing the Effects of Anthropogenic Sound on Marine 
Mammal Hearing (Version 2.0) (Technical Guidance, 2018) identifies dual 
criteria to assess auditory injury (Level A harassment) to five 
different marine mammal groups (based on hearing sensitivity) as a 
result of exposure to noise from two different types of sources 
(impulsive or non-impulsive). BNSF's planned activity includes the use 
of impulsive (impact pile driving) and non-impulsive (vibratory pile 
driving) sources.
    These thresholds are provided in Table 3 below. The references, 
analysis, and methodology used in the development of the thresholds are 
described in NMFS 2018 Technical Guidance, which may be accessed at 
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

                     Table 3--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
                                                    PTS onset acoustic thresholds *  (received level)
             Hearing group              ------------------------------------------------------------------------
                                                  Impulsive                         Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans...........  Cell 1: Lpk,flat: 219 dB;   Cell 2: LE,LF,24h: 199 dB.
                                          LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans...........  Cell 3: Lpk,flat: 230 dB;   Cell 4: LE,MF,24h: 198 dB.
                                          LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans..........  Cell 5: Lpk,flat: 202 dB;   Cell 6: LE,HF,24h: 173 dB.
                                          LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater).....  Cell 7: Lpk,flat: 218 dB;   Cell 8: LE,PW,24h: 201 dB.
                                          LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater)....  Cell 9: Lpk,flat: 232 dB;   Cell 10: LE,OW,24h: 219 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.
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]Pa\2\s. In this Table, thresholds are abbreviated to reflect American National
  Standards Institute standards (ANSI 2013). However, peak sound pressure is defined by ANSI as incorporating
  frequency weighting, which is not the intent for this Technical Guidance. Hence, the subscript ``flat'' is
  being included to indicate peak sound pressure should be flat weighted or unweighted within the generalized
  hearing range. The subscript associated with cumulative sound exposure level thresholds indicates the
  designated marine mammal auditory weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds) and
  that the recommended accumulation period is 24 hours. The cumulative sound exposure level thresholds could be
  exceeded in a multitude of ways (i.e., varying exposure levels and durations, duty cycle). When possible, it
  is valuable for action proponents to indicate the conditions under which these acoustic thresholds will be
  exceeded.

Ensonified Area

    Here, we describe operational and environmental parameters of the 
activity that will feed into identifying the area ensonified above the 
acoustic thresholds, which include source levels and transmission loss 
coefficient.

[[Page 22510]]

    The following pile sizes and installation/extraction methods were 
analyzed:
     36-inch steel pipe pile, impact installation, with 5 dB 
bubble curtain source level reduction under two installation scenarios 
(1 pile driver or 2 concurrent pile drivers);
     48-inch steel pipe pile, oscillator installation (drilled 
shaft);
     48-inch steel pipe pile, diamond wire saw cutting;
     14-inch steel H-pile, vibratory installation/extraction;
     12-inch timber pile, vibratory installation/extraction; 
and
     12-inch timber pile, pile clipper extraction.
    Impact pile driver installation of 36-inch steel pipe piles 
analyzed a worst-case scenario consisting of two crews driving 36-inch 
steel pipe piles simultaneously (Scenario 2) in order to provide 
maximum flexibility should multiple crews become necessary during 
construction. It is likely, however, that only one crew will operate at 
one time (Scenario 1). Based on NMFS guidance, decibel addition is not 
considered in the 36-inch steel pipe pile impact analysis since during 
impact hammering or other impulsive sources, it is unlikely that the 
two hammers would strike at the same exact instant (or within the 0.1 
second average pulse duration). Therefore, the sound source levels will 
not be adjusted regardless of the distance between the hammers and each 
source will be analyzed separately.
    Vibratory pile driving of 14-inch H-piles, and vibratory and pile 
clipper extraction of 12-inch timber piles (residential structures 
demolition) were analyzed in the event these methods become necessary 
(if, for instance, crane weight alone cannot seat the 14-inch H-piles 
for the turbidity screen installation or crane torque alone cannot 
extract timber piles by direct pulling/twisting).
    This analysis uses in-water source sound levels for vibratory and 
impact pile driving from Washington State Department of Transportation 
Biological Assessment Manual (WDSOT 2020), and California Department of 
Transportation Division (Caltrans 2015). Analysis of drilled shaft 
installation used sound source data came from (HDR, 2011. Diamond wire 
saw cutting and hydraulic pile clipper cutting came from the Navy 
(2019). Source sound levels for each analysis were measured at 10m from 
the source and based on other projects with the same pile type and 
size, installation/extraction technique, and similar substrate if no 
project site-specific information is available.
    In cases where multiple sources were provided from the above 
references, the following methodology was used to select in-water 
source sound levels to generate a proxy:
    1. Select first by corresponding pile size and type;
    2. Eliminate those that do not have substrates similar to the 
project site substrate (i.e., sandy silt intermixed with gravels and 
riprap); and
    3. Of the remaining, select highest source sound level to be 
conservative.
    All piles driven and/or proofed with an impact hammer would use a 
bubble curtain. It is estimated that use of a bubble curtain would 
result in a minimum of a 5-dB reduction in underwater sound levels 
during 36-inch pipe pile driving, and this reduction has been included 
in the estimate to account for a reasonably achievable reduction in 
sound during underwater construction activity. Source sound levels are 
summarized in Table 4.

                                      Table 4--In-Water Sound Source Levels
----------------------------------------------------------------------------------------------------------------
                                                                                                       dB single-
    Pile size          Pile type              Source        Construction method   dB peak     dB RMS     strike
                                                                                                          SEL
----------------------------------------------------------------------------------------------------------------
36 inch.........  Steel pipe.........  Caltrans, 2015. 36-  Impact.............        208        190        180
                                        inch steel pipe
                                        pile Table I.2-1.
14 inch.........  H-pile.............  Caltrans, 2015. 12-  Vibratory..........  .........        150  .........
                                        inch steel H-pile
                                        proxy Table I.2-2.
12 inch.........  Timber Pile........  Greenbusch Group,    Vibratory..........  .........        152  .........
                                        2018. 12-inch
                                        timber pile.
12 inch.........  Timber Pile........  NAVFAC SW 2020       Hydraulic Pile       .........        154  .........
                                        Compendium. 13-      Clipper.
                                        inch round
                                        polycarbonate pile.
48-inch.........  Steel Shaft........  HDR Alaska, Inc.,    Oscillator.........  .........      143.8  .........
                                        2011. 144-inch
                                        steel shaft proxy.
48-inch.........  Steel-encased        NAVFAC SW 2020       Diamond bladed wire  .........      161.5  .........
                   Concrete Shaft.      Compendium. 66-      saw.
                                        inch steel encased
                                        concrete-filled
                                        caisson proxy.
----------------------------------------------------------------------------------------------------------------

    Transmission loss (TL), expressed as decibels, is the reduction in 
a specified level between two specified points R1, 
R2 that are within an underwater acoustic field. By 
convention, R1 is chosen to be closer to the source of sound 
than R2, such that transmission loss is usually a positive 
quantity. TL parameters vary with frequency, temperature, sea 
conditions, current, source and receiver depth, water depth, water 
chemistry, and bottom composition and topography. The general formula 
for underwater TL is:

TL = B * Log10 (R2/R1),

Where

TL = transmission loss in dB
B = transmission loss coefficient
R1 = distance from source to distance at which the level 
is estimated (typically 10-m for pile driving)
R2 = distance from source to the isopleth associated with 
the applicable acoustic threshold

    Absent site-specific acoustical monitoring with differing measured 
transmission loss, a practical spreading value of 15 is used as the 
transmission loss coefficient in the above formula. Site-specific 
transmission loss data for BNSF bridge site is not available, therefore 
the default coefficient of 15 is used to determine the distances to the 
Level A and Level B harassment thresholds.
    When the NMFS Technical Guidance (2016) was published, in 
recognition of the fact that ensonified area/volume could be more 
technically challenging to predict because of the duration component in 
the new thresholds, we developed a User Spreadsheet that includes tools 
to help predict a simple isopleth that can be used in conjunction with 
marine mammal density or occurrence to help predict takes. We note that 
because of some of the assumptions included in the methods used for 
these tools, we anticipate that isopleths produced are typically going 
to be overestimates of some degree, which may result in some degree of 
overestimate of Level A harassment take. However, these tools offer the 
best way to predict appropriate isopleths when more sophisticated 3D 
modeling methods are not available, and NMFS continues to develop ways 
to quantitatively refine these tools, and will qualitatively address 
the output where appropriate. For stationary sources, NMFS User 
Spreadsheet predicts the distance at which, if a marine mammal remained 
at that distance the whole duration of the activity, it would incur 
PTS. Inputs used in the User Spreadsheet are shown in Table 5 and the 
resulting isopleths are reported below in Table 6.

[[Page 22511]]



                              Table 5--User Spreadsheet Input Parameters Used for Calculating Level A Harassment Isopleths
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  36-inch steel--  14-inch steel  H-  12-inch timber
                                 36-inch steel     2 concurrent     pile vibratory       vibratory      48-inch steel     48-inch wire    12-inch timber
                                 (scenario 1)      (scenario 2)         install         extraction        oscillator      saw cutting    clipper cutting
--------------------------------------------------------------------------------------------------------------------------------------------------------
Spreadsheet Tab Used.........  (E.1) Impact      (E.1) Impact      (A.1) Vibratory   (A.1) Vibratory   (A) stationary   (A) stationary   (A) stationary
                                pile driving.     pile driving.     pile driving.     pile driving.     source (non-     source (non-     source (non-
                                                                                                        impulsive,       impulsive,       impulsive,
                                                                                                        continuous).     continuous).     continuous).
Source Level (Single Strike/   175 SEL/203 Peak  175 SEL/203 Peak  150 RMS.........  152 RMS.........  143.8 RMS......  161.5 RMS......  154 RMS.
 shot SEL) and Peak or RMS.
Weighting Factor Adjustment    2...............  2...............  2.5.............  2.5.............  2.5............  2.5............  2.5.
 (kHz).
(a) Number of strikes per      1000............  1000............
 pile.
Number piles or shafts per     6...............  12..............  8...............  10..............  0.25...........  4..............  20.
 day.
Duration for single pile       ................  ................  30..............  15..............  1920...........  60.............  4.
 (min).
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Transmission loss coefficient for all sources is 15 and all source level values quoted are at 10m distance.


                                        Table 6--Calculated Distances to Level A and Level B Harassment Isopleths
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                 Level A zone (meters)                         Level B
                                                                           -----------------------------------------------------------------  harassment
                 Pile type, size, and pile driving method                        LF           MF           HF                                    zone
                                                                              cetacean     cetacean     cetacean      Phocid      Otariid      (meters)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Scenario 1. 36-inch Steel Pipe Impact Drive (Year 1)......................          966           34        1,150          517           38          464
Scenario 2. 36-inch Steel Pipe Impact Drive (Year 1)......................        1,533           55        1,826          820           60          464
14-inch H-Pile Vibratory (Year 1, Year 2).................................            3            1            5            2            1        1,000
12-inch Timber Vibratory (Year 1).........................................            3            1            5            2            1        1,359
48-inch Drilled Shaft Oscillatory Installation (Year 1)...................          0.2            0          0.2          0.1            0          386
48-inch Concrete-lined Steel Shaft Diamond Wire Saw Removal (Year 2)......          1.9          0.2          2.7          1.1          0.1        5,843
12-inch Timber Pile Clipper (Year 1)......................................          0.6            0          0.6          0.3            0        1,848
--------------------------------------------------------------------------------------------------------------------------------------------------------

Marine Mammal Occurrence and Take Calculation and Estimation

    In this section we provide the information about the presence, 
density, or group dynamics of marine mammals and how it is brought 
together to produce a quantitative take estimate.
    Take estimates were calculated using a combination of best 
available data. Best available density data was for the most part from 
the U.S. Department of the Navy's Marine Species Density Database Phase 
III for the Northwest Training and Testing Study Area (Navy 2019) which 
includes seasonal density estimates: Winter (Dec-Feb), Spring (Mar-
May), Summer (Jun-Aug), Fall (Sep-Nov). The project will not work in-
water in the Spring as that season is outside the July 16-February 15 
in-water work season. The most conservative (highest density) seasonal 
estimate from the remaining three seasons was used where seasonal 
overlap exists and densities differ across seasons. Estimated take was 
calculated using density estimates multiplied by the area of each Level 
B harassment zone for each pile type multiplied by the number of days 
of in-water activity for each pile type. In some instances and where 
noted, observation-based data from WSDOT's Seattle Multimodal Project 
at Colman Dock Season Three Marine Mammal Monitoring Report (WSDOT 
2020a) or other observational data was used instead of U.S. Navy data 
when Navy density data was zero or extremely low.
    BNSF plans to work in-water for 113 days in Year 1 and 9 days in 
Year 2, or approximately 5.5 months assuming a 5-day work week for 23 
weeks in Year 1 and a half a month assuming a 5-day work week for 2 
weeks in Year 2,

Minke Whale

    The estimated take was calculated as described above using the 
Navy's density data which resulted in zero takes of minke whale for 
both Year 1 and Year 2 as shown in Table 7. Therefore, as described 
above, we looked at other observational data. The WSDOT Seattle 
Multimodal Project at Colman Dock Year 3 IHA Monitoring Report observed 
minke whale presence indicates sightings of a single minke whale over 7 
months (WSDOT 2020a). Given this information, BNSF and NMFS 
conservatively assumed that up to one whale per month could be taken by 
harassment.
    A shutdown zone at the full distance of the level A harassment 
isopleths (<= 1533 m) will be applied to avoid take by Level A 
harassment.
    The 113 days of work in Year 1 and 9 days in Year 2, equates to 5.5 
months x 1 minke whale/month = 6 encounters with minke whales in Year 1 
and 0.5 months x 1 Minke whale/month = 1 whale in Year 2. Therefore, 
BNSF has requested and NMFS has authorized 6 takes by Level B 
harassment in Year 1 and 1 take by Level B harassment in year in Year 
2.

                                                         Table 7--Calculated Take of Minke Whale
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Species
                                            density     Level A    Level B                                      Year 1     Year 1     Year 2     Year 2
                Activity                   (animals/      area       area       Length of activity (days)     estimated  estimated  estimated  estimated
                                             km\2\)     (km\2\)    (km\2\)                                      take A     take B     take A     take B
--------------------------------------------------------------------------------------------------------------------------------------------------------
Impact 36-inch Steel Pipe Pile (2           0.0000054      0.376      0.183  10 (Yr 1)......................          0          0  .........  .........
 Concurrent Drivers).
Vibratory 14-inch H-Pile................    0.0000054      0.005      0.235  6 (3 Yr 1, 3 Yr 2).............          0          0          0          0
Vibratory 12-inch Timber Pile...........    0.0000054      0.005      0.286  8 (Yr 1).......................          0          0  .........  .........

[[Page 22512]]

 
Oscillator Install of 4-foot Drilled        0.0000054      0.000      0.169  88 (Yr 1)......................          0          0  .........  .........
 Shaft.
Diamond Wire Saw Removal of 48-inch         0.0000054      0.000      2.290  6 (Yr 2).......................  .........  .........          0          0
 Drilled Shaft.
24-inch Pile Clipper Removal of 12-inch     0.0000054      0.000      0.381  4 (Yr 1).......................          0          0  .........  .........
 Timber Pile.
--------------------------------------------------------------------------------------------------------------------------------------------------------

Common Bottlenose Dolphin

    Estimated take using the Navy's density estimates for common 
bottlenose dolphins as described above resulted in zero take in both 
Year 1 and Year 2 as shown in Table 8. Therefore, as described above, 
we looked at other observational data. Common bottlenose dolphins have 
been rare visitors to Puget Sound. However, the WSDOT Seattle 
Multimodal Project at Colman Dock Year 3 IHA monitoring report observed 
common bottlenose dolphin at a rate of 6 per month (WSDOT 2020a). In-
water work will occur for 113 days in Year 1 and 9 days in Year 2, 
which would equate to 33 dolphin takes in Year 1 (5.5 months x 6 
dolphins/month) and 3 dolphin takes in Year 2 (0.5 months x 3 dolphins/
month). A shutdown zone at the full distance of the level A harassment 
isopleths (<=55m) can be effectively applied to avoid Level A take. 
Therefore, BNSF has requested and NMFS has authorized 33 takes by Level 
B harassment in Year 1 and 3 takes by Level B harassment in year in 
Year 2.

                                                     Table 8--Calculated Take of Bottlenose Dolphin
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Species
                                            density     Level A    Level B                                      Year 1     Year 1     Year 2     Year 2
                Activity                   (animals/      area       area       Length of activity (days)     estimated  estimated  estimated  estimated
                                             km\2\)     (km\2\)    (km\2\)                                      take A     take B     take A     take B
--------------------------------------------------------------------------------------------------------------------------------------------------------
Impact 36-inch Steel Pipe Pile (2           0.0000054      0.376      0.183  10 (Yr 1)......................          0          0  .........  .........
 Concurrent Drivers).
Vibratory 14-inch H-Pile................    0.0000054      0.005      0.235  6 (3 Yr 1, 3 Yr 2).............          0          0          0          0
Vibratory 12-inch Timber Pile...........    0.0000054      0.005      0.286  8 (Yr 1).......................          0          0  .........  .........
Oscillator Install of 4-foot Drilled        0.0000054      0.000      0.169  88 (Yr 1)......................          0          0  .........  .........
 Shaft.
Diamond Wire Saw Removal of 48-inch         0.0000054      0.000      2.290  6 (Yr 2).......................  .........  .........          0          0
 Drilled Shaft.
24-inch Pile Clipper Removal of 12-inch     0.0000054      0.000      0.381  4 (Yr 1).......................          0          0  .........  .........
 Timber Pile.
                                         ---------------------------------------------------------------------------------------------------------------
    Total...............................  ...........  .........  .........  122............................          0          0          0          0
--------------------------------------------------------------------------------------------------------------------------------------------------------

Long-Beaked Common Dolphin

    Using the Navy's density data, which was zero, estimated take of 
common dolphins was calculated to be zero in Year 1 and Year 2. 
Therefore, as described above, we looked at other observational data. 
Sightings of live dolphins throughout inside waters and Southern Puget 
Sound have been recorded in 2003, 2011-12, and 2016-17. Group size 
ranged from 2 (in 2003 and 2011-12) to 5-12 (in 2016-2017) (Shuster et 
al. 2017). Since June 2016, several common dolphins have remained in 
Puget Sound, group sizes of 5-20 individuals are often reported and 
some of these groups stayed in the region for several months. Sightings 
of these animals mostly began in summer and early fall sometimes 
extending into winter months. (Shuster et al., 2018). We conservatively 
predict that a group of 20 individuals will be taken on a monthly 
basis. The Level A harassment shutdown zone for mid-frequency hearing 
group will be implemented to minimize the severity of any Level A 
harassment that could occur. The in-water work would occur for 113 days 
in Year 1 and 9 days in Year 2, which would result in 110 takes (5.5 
months x 20 dolphins/month) in Year 1 and 20 takes (1 month x 20 
dolphins/month) in Year 2 by Level B harassment. BNSF has requested and 
NMFS has authorized 110 takes of long-beaked common dolphin by Level B 
harassment in Year 1 and 10 takes by Level B harassment in year in Year 
2.

Harbor Porpoise

    Harbor porpoise density estimates based on the Navy's data were 
used to calculate requested and authorized take as shown in Table 9. 
Analysis of the size of the level A harassment zones multiplied by 
density associated with harbor porpoise predicted that two porpoises 
could be taken by Level A harassment during the 10 days that concurrent 
driving of 36-in steel piles occurs during year 1. However, take by 
Level A harassment is unlikely given that the threshold and associated 
PTS isopleth is based on the acoustic energy accrued over a specified 
time period and it is unlikely that a highly mobile animal such as the 
harbor porpoise would spend the that amount if time in the Level A 
harassment zone. However, given the larger size of the zone and the 
cryptic nature of harbor porpoises, we have precautionarily authorized 
2 takes by Level A harassment for Year 1. The Level A harassment shut 
down zone for high frequency hearing group will be implemented to 
minimize severity of any Level A harassment takes that do occur. Since 
there will be no impact driving during Year 2, the size of the Level A 
harassment zone will not exceed 5 m and, therefore, no take by Level A 
harassment was requested and none has been authorized. BNSF has 
requested and NMFS has authorized 12 takes of harbor porpoise by Level 
B harassment in Year 1 and 8 takes by Level B harassment in year in 
Year 2.

                                                       Table 9--Calculated Take of Harbor Porpoise
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Species
                                            density     Level A    Level B                                      Year 1     Year 1     Year 2     Year 2
                Activity                   (animals/      area       area       Length of activity (days)     estimated  estimated  estimated  estimated
                                             km\2\)     (km\2\)    (km\2\)                                      take A     take B     take A     take B
--------------------------------------------------------------------------------------------------------------------------------------------------------
Impact 36-inch Steel Pipe Pile (2                0.54      0.376      0.183  10 (Yr 1)......................          2          1  .........  .........
 Concurrent Drivers).

[[Page 22513]]

 
Vibratory 14-inch H-Pile................         0.54      0.005      0.235  6 (3 Yr 1, 3 Yr 2).............          0          1          0          1
Vibratory 12-inch Timber Pile...........         0.54      0.005      0.286  8 (Yr 1).......................          0          1  .........  .........
Oscillator Install of 4-foot Drilled             0.54      0.000      0.169  88 (Yr 1)......................          0          8  .........  .........
 Shaft.
Diamond Wire Saw Removal of 48-inch              0.54      0.000      2.290  6 (Yr 2).......................  .........  .........          0          7
 Drilled Shaft.
24-inch Pile Clipper Removal of 12-inch          0.54      0.000      0.381  4 (Yr 1).......................          0          1  .........  .........
 Timber Pile.
                                         ---------------------------------------------------------------------------------------------------------------
    Total...............................  ...........  .........  .........  122............................          2         12          0          8
--------------------------------------------------------------------------------------------------------------------------------------------------------

Harbor Seal

    Harbor seal density estimates based on data from the Navy were 
initially used to calculate requested and authorized take (Table 10). 
These estimates, however, do not account for numerous seals feeding on 
migrating salmonids at Ballard Locks, especially during.summer (June-
September) months. A new acoustic deterrent device was tested over two 
years to keep seals away from the Locks (Bogaard, Pers. Comm, 2022). A 
study report is currently being developed for publication. Study 
observers were primarily focused on behavioral effects of the deterrent 
on seals and monitored seal behavioral reactions during 30 minute 
observation periods up to eight times per day. Actual seal abundance 
was not recorded. However, observers noted that groups of 5-6 harbor 
seals were very common from late June through September during the 
salmon run, although smaller numbers were present throughout the year. 
It is likely that many of the same animals were observed multiple times 
across daily observation periods. The in-water work window runs from 
July 16, 2022 through February 15, 2023. Given this information, NMFS 
assumed for Year 1 that during the 54 in-water work days between July 
16, 2022 and September 30, 2022, 5 harbor seals would be taken per day 
(270 takes). For the remaining 59 in-water work days between October 1, 
2022 and February 15, 2023, a single harbor seal would be taken per day 
(59) for a total of 329 takes. There are 10 in-water work days that 
include concurrent impact driving of 36-inch piles when the Level A 
harassment isopleth is relatively large (1,826 m) (and also exceeds the 
Level B harassment isopleth (464 m)) so it is possible that Level A 
harassment could occur in some animals. Also, note that the constrained 
design of the lock system means that seals would likely spend extended 
periods in the confined area while feeding. NMFS conservatively assumes 
that all of these 10 in-water work days would occur during salmon 
migration (February 15-Sept 30) and that up to one-third of seals taken 
per day (2) could be exposed to sound energy levels resulting in some 
degree of Level A harassment (20). The estimated takes by Level A 
harassment is subtracted from the Level B harassment take to avoid 
double-counting. Since a smaller number of seals expected to be present 
during non-migratory period and the seals would have little incentive 
to congregate near the locks in the absence of salmon, NMFS does not 
expect any Level A harassment of seals to occur. Therefore, NMFS is 
proposing during Year 1 to authorize 20 takes by Level A harassment and 
309 takes by Level B harassment (329-20).
    For Year 2, NMFS assumed that all 9 in-water work days would occur 
during salmon migration between July 16, 2023 and September 30, 2024 
with up to 6 harbor seals taken per day (54). No Level A take 
harassment is authorized during Year 2 since the largest Level A 
isopleth for all planned activities is 2 m. However, the density-based 
estimate was 57 takes as shown in Table 10. Therefore, NMFS is 
proposing 57 takes of harbor seal by Level B harassment during Year 2.

                                                        Table 10--Calculated Take of Harbor Seal
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Species
                                            density     Level A    Level B                                      Year 1     Year 1     Year 2     Year 2
                Activity                   (animals/      area       area       Length of Activity (days)     estimated  estimated  estimated  estimated
                                             km\2\)     (km\2\)    (km\2\)                                      take A     take B     take A     take B
--------------------------------------------------------------------------------------------------------------------------------------------------------
Impact 36-inch Steel Pipe Pile (2                3.91      0.215      0.183  10 (Yr 1)......................          8          7  .........  .........
 Concurrent Drivers).
Vibratory 14-inch H-Pile................         3.91      0.005      0.235  6 (3 Yr 1, 3 Yr 2).............          0          3          0          3
Vibratory 12-inch Timber Pile...........         3.91      0.005      0.286  8 (Yr 1).......................          0          9  .........  .........
Oscillator Install of 4-foot Drilled             3.91      0.005      0.169  88 (Yr 1)......................          0         58  .........  .........
 Shaft.
Diamond Wire Saw Removal of 48-inch              3.91      0.005      2.290  6 (Yr 2).......................  .........  .........          0         54
 Drilled Shaft.
24-inch Pile Clipper Removal of 12-inch          3.91      0.005      0.381  4 (Yr 1).......................          0          6  .........  .........
 Timber Pile.
                                         ---------------------------------------------------------------------------------------------------------------
    Total...............................  ...........  .........  .........  122............................          8         83          0         57
--------------------------------------------------------------------------------------------------------------------------------------------------------

California Sea Lion

    BNSF initially considered California sea lion density estimates to 
calculate requested take, which resulted in relatively low estimates (4 
takes in Year 1 and 3 takes in Year 2 by Level B harassment) as shown 
in Table 11. However, California sea lions are known to frequent the 
Ballard Locks to feed on migrating salmon (KUOW, 2020). While no formal 
research studies have recorded individual numbers of California sea 
lions at Ballard Locks, news articles reported accounts of California 
sea lion sightings which ranged from a few to many more (Hakai 
Magazine, 2018; King 5 News, 2021). Observers associated with the 
acoustic deterrent device study described above, reported that 
California sea lions were less numerous than harbor seals, having been 
seen at a rate of 2-3 per day during peak salmonid migration (Bogaard, 
Pers. Comm. 2022). They were less common during non-migratory seasons. 
Given this information, NMFS assumed for Year 1 that during the 54 in-
water work days between July 16, 2022 and September 30, 2022, 2 
California sea lions would be taken per day (108). For the remaining 59 
in-water work days between October 1, 2022 and February 15, 2023, a 
single California sea lion

[[Page 22514]]

would be taken very third day (20). Take by Level A harassment is 
possible, but unlikely, given that the largest Level A harassment 
isopleth is 60 m (with a 10 m shutdown zone for otariids) but only 
during 10 in-water work days which would include impact driving during 
Year 1. The Level A harassment zone during all other in-water work days 
in both Year 1 and Year 2 is 1 m or less. A California sea lion would 
not be expected to remain within the injury zone long enough (5.4 
hours) to accrue the amount energy that would result in take Level A 
harassment. As such, NMFS is proposing during Year 1 to authorize 128 
takes by Level B harassment. No takes by Level A harassment are 
authorized.
    For Year 2, NMFS assumed that all 9 in-water work days would occur 
during peak salmon migration between July 16, 2023 and September 30, 
2024 with up to 2 California sea lions taken per day (18). NMFS is 
proposing to authorize 18 takes of California sea lion by Level B 
harassment. No Level A take harassment is authorized.

                                         Table 11--Calculated Take of California Sea Lions by Level B Harassment
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Species
                                            density     Level A    Level B                                      Year 1     Year 1     Year 2     Year 2
                Activity                   (animals /     area       area       Length of activity  (days)    estimated  estimated  estimated  estimated
                                             km\2\)     (km\2\)    (km\2\)                                      take A     take B     take A     take B
--------------------------------------------------------------------------------------------------------------------------------------------------------
Impact 36-inch Steel Pipe Pile (2              0.2211      0.023      0.183  10 (Yr 1)......................          0          0  .........  .........
 Concurrent Drivers).
Vibratory 14-inch H-Pile................       0.2211      0.004      0.235  6 (3 Yr 1, 3 Yr 2).............          0          0          0          0
Vibratory 12-inch Timber Pile...........       0.2211      0.004      0.286  8 (Yr 1).......................          0          1  .........  .........
Oscillator Install of 4-foot Drilled           0.2211      0.000      0.169  88 (Yr 1)......................          0          3  .........  .........
 Shaft.
Diamond Wire Saw Removal of 48-inch            0.2211      0.000      2.290  6 (Yr 2).......................  .........  .........          0          3
 Drilled Shaft.
24-inch Pile Clipper Removal of 12-inch        0.2211      0.000      0.381  4 (Yr 1).......................          0          0  .........  .........
 Timber Pile.
                                         ---------------------------------------------------------------------------------------------------------------
    Total...............................  ...........  .........  .........  ...............................  .........          4  .........          3
--------------------------------------------------------------------------------------------------------------------------------------------------------

Stellar Sea Lion

    Stellar sea lion density estimates were initially used to calculate 
requested take as shown in Table 12. Based on the density data, BNSF 
has requested a single take for both Year 1 and Year 2. Given the large 
number of in-water work days in Year 1, NMFS has precautionarily 
increased the authorized Level B harassment to 5 takes while 
maintaining the 1 authorized by Level B harassment as calculated by 
density estimates in Year 2. Monitors with the acoustic deterrent study 
did not observe any Steller sea lions during the two years that the 
study was underway (Bogaard, Pers. Comm, 2022).

                                          Table 12--Calculated Take of Steller Sea Lions by Level B Harassment
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Species
                                            density     Level A    Level B                                      Year 1     Year 1     Year 2     Year 2
                Activity                   (animals /     area       area       Length of activity  (days)    estimated  estimated  estimated  estimated
                                             km\2\)     (km\2\)    (km\2\)                                      take A     take B     take A     take B
--------------------------------------------------------------------------------------------------------------------------------------------------------
Impact 36-inch Steel Pipe Pile (2              0.0478      0.023      0.183  10 (Yr 1)......................          0          0  .........  .........
 Concurrent Drivers).
Vibratory 14-inch H-Pile................       0.0478      0.004      0.235  6 (3 Yr 1, 3 Yr 2).............          0          0          0          1
Vibratory 12-inch Timber Pile...........       0.0478      0.004      0.286  8 (Yr 1).......................          0          0  .........  .........
Oscillator Install of 4-foot Drilled           0.0478      0.000      0.169  88 (Yr 1)......................          0          1  .........  .........
 Shaft.
Diamond Wire Saw Removal of 48-inch            0.0478      0.000      2.290  6 (Yr 2).......................  .........  .........          0          0
 Drilled Shaft.
24-inch Pile Clipper Removal of 12-inch        0.0478      0.000      0.381  4 (Yr 1).......................          0          0  .........  .........
 Timber Pile.
                                         ---------------------------------------------------------------------------------------------------------------
    Total...............................  ...........  .........  .........  ...............................  .........          1  .........          1
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The estimated take by Level A and Level B harassment for all 
authorized species and stocks by year, and percentage take by stock is 
shown in Table 13.

                  Table 13--Estimated Take by Level A and Level B Harassment, by Species, Stock and Year, and Percentage Take by Stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                           IHA Year 1       Total take       IHA Year 2       Total take
                                                                                     ----------------------     as     ----------------------     as
               Common name                             Stock              Abundance     Take A     Take B   percentage    Take A     Take B   percentage
                                                                                       request    request    of stock    request    request    of  stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
Minke Whale..............................  California/Oregon/Washington          915  .........          6        0.66  .........          1        0.11
Common Bottlenose Dolphin................  California/Oregon/Washington        3,477  .........         33        0.95  .........          3        0.09
                                            offshore.
Long-beaked Common Dolphin...............  California..................       83,379  .........        110        0.13  .........         20        0.01
Harbor Porpoise..........................  Washington Inland Waters....       11,233  .........         12        0.11  .........          8        0.07
Harbor Seal..............................  Washington Northern Inland          1,088         20        309        32.6  .........         57         5.2
                                            Waters.
California Sea Lion......................  United States...............      257,606  .........        108        0.04  .........         20       <0.01
Stellar Sea Lion.........................  Eastern U.S.................       43,201  .........          5        0.01  .........          1       <0.01
--------------------------------------------------------------------------------------------------------------------------------------------------------

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 the 
activity, and other means of effecting the least practicable impact on 
the species or stock and its habitat, paying particular attention to 
rookeries, mating grounds,

[[Page 22515]]

and areas of similar significance, and on the availability of the 
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 the activity or other means of 
effecting the least practicable adverse impact upon the affected 
species or stocks and their habitat (50 CFR 216.104(a)(11)).
    In evaluating how mitigation may or may not be appropriate to 
ensure the least practicable adverse impact on species or stocks and 
their habitat, as well as subsistence uses where applicable, we 
carefully consider two primary factors:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure(s) is expected to reduce impacts to 
marine mammals, marine mammal species or stocks, and their habitat. 
This considers the nature of the potential adverse impact being 
mitigated (likelihood, scope, range). It further considers the 
likelihood that the measure will be effective if implemented 
(probability of accomplishing the mitigating result if implemented as 
planned), the likelihood of effective implementation (probability 
implemented as planned); and
    (2) The practicability of the measures for applicant 
implementation, which may consider such things as cost, impact on 
operations, and, in the case of a military readiness activity, 
personnel safety, practicality of implementation, and impact on the 
effectiveness of the military readiness activity.
    In addition to the measures described later in this section, BNSF 
will employ the following mitigation measures:
     BNSF must ensure that construction supervisors and crews, 
the monitoring team, and relevant BNSF staff are trained prior to the 
start of activities subject to these IHAs, so that responsibilities, 
communication procedures, monitoring protocols, and operational 
procedures are clearly understood. New personnel joining during the 
project must be trained prior to commencing work;
     Monitoring must take place from 30 minutes prior to 
initiation of pile driving activity (i.e., pre-start clearance 
monitoring) through 30 minutes post-completion of pile driving 
activity;
     If a marine mammal is observed entering or within the 
shutdown zones indicated in Table 14, pile driving activity must be 
delayed or halted;
     Pile driving activity must be halted upon observation of 
either a species for which incidental take is not authorized or a 
species for which incidental take has been authorized but the 
authorized number of takes has been met, entering or within the 
harassment zone (as shown in Table 14); and
     BNSF, construction supervisors and crews, Protected 
Species Observers (PSOs), and relevant BNSF staff must avoid direct 
physical interaction with marine mammals during construction activity. 
If a marine mammal comes within 10 meters of such activity, operations 
must cease and vessels must reduce speed to the minimum level required 
to maintain steerage and safe working conditions, as necessary to avoid 
direct physical interaction.
    The following mitigation measures apply to BNSF's in-water 
construction activities:
     Establishment of Shutdown Zones--BNSF will establish 
shutdown zones for all pile driving and removal activities. The purpose 
of a shutdown zone is generally to define an area within which shutdown 
of the activity would occur upon sighting of a marine mammal (or in 
anticipation of an animal entering the defined area). Shutdown zones 
will vary based on the activity type and marine mammal hearing group. 
In addition to the shutdown zones listed in Table 14, BNSF will shut 
down construction activity if a humpback or southern resident killer 
whale is observed approaching or within the specified Level B 
harassment zone.
     Protected Species Observers--The placement of PSOs during 
all pile driving and removal activities (described in detail in the 
Monitoring and Reporting section) will ensure that the entire shutdown 
zone is visible during pile driving and removal. Should environmental 
conditions deteriorate such that marine mammals within the entire 
shutdown zone would not be visible (e.g., fog, heavy rain), drilling, 
cutting, clipping, pile driving and removal must be delayed until the 
PSO is confident marine mammals within the shutdown zone could be 
detected.

    Table 14--Shutdown Zones for Each Hearing Group and Level B Harassment Zones During Pile Installation and
                                                     Removal
                                                    [meters]
----------------------------------------------------------------------------------------------------------------
                                                                                                       Level B
 Pile type, size, and pile driving       LF           MF           HF         Phocid      Otariid     harassment
              method                                                                                     zone
----------------------------------------------------------------------------------------------------------------
Scenario 1. Single 36-inch Pipe...        1,000           40        1,200           10           10          500
Scenario 2. 2 Concurrent 36-inch          1,600           60        1,900           10           10          500
 Pipe.............................
14-inch H-Pile....................           10           10           10           10           10        1,000
12-inch Timber Vibratory..........           10           10           10           10           10        1,400
48-inch Drilled Shaft Oscillatory            10           10           10           10           10          400
 Installation.....................
48-inch Concrete-lined Steel Shaft           10           10           10           10           10        5,900
 Diamond Wire Saw Removal.........
12-inch Timber Pile Clipper.......           10           10           10           10           10        1,900
----------------------------------------------------------------------------------------------------------------

     Monitoring for Level A and Level B Harassment--BNSF will 
monitor the Level B harassment zones to the extent practicable and the 
entire Level A harassment zones. Monitoring zones provide utility for 
observing by establishing monitoring protocols for areas adjacent to 
the shutdown zones. Monitoring zones enable observers to be aware of 
and communicate the presence of marine mammals in the project area 
outside the shutdown zone and thus prepare for a potential cessation of 
activity should the animal enter the shutdown zone. At least three PSOs 
would monitor harassment zones during all in-water construction 
activities. PSO monitoring stations are described below in the 
Monitoring and Reporting section.
     Pre-activity Monitoring--Prior to the start of daily in-
water construction activity, or whenever a break in drilling, clipping, 
cutting, pile driving/removal

[[Page 22516]]

of 30 minutes or longer occurs, PSOs will observe the shutdown and 
monitoring zones for a period of 30 minutes. The shutdown zone will be 
considered cleared when a marine mammal has not been observed within 
the zone for that 30-minute period. If a marine mammal is observed 
within the shutdown zone, a soft-start cannot proceed until the animal 
has left the zone or has not been observed for 15 minutes. When a 
marine mammal for which Level B harassment take is authorized is 
present in the Level B harassment zone, activities may begin and Level 
B harassment take will be recorded. If the entire Level B harassment 
zone is not visible at the start of construction, pile driving 
activities can begin. If work ceases for more than 30 minutes, the pre-
activity monitoring of the shutdown zones will commence.
     Soft Start--Soft-start procedures are believed to provide 
additional protection to marine mammals by providing warning and/or 
giving marine mammals a chance to leave the area prior to the hammer 
operating at full capacity. For impact pile driving, contractors will 
be required to provide an initial set of three strikes from the hammer 
at reduced energy, followed by a 30-second waiting period. This 
procedure will be conducted three times before impact pile driving 
begins. Soft start will be implemented at the start of each day's 
impact pile driving and at any time following cessation of impact pile 
driving for a period of 30 minutes or longer.
     Bubble Curtain--BNSF will use a marine pile-driving energy 
attenuator (i.e., air bubble curtain system) during impact pile 
driving. The use of sound attenuation will reduce SPLs and the size of 
the zones of influence for Level A harassment and Level B harassment. 
Bubble curtains will meet the following requirements:
    [cir] The bubble curtain must distribute air bubbles around 100 
percent of the piling circumference for the full depth of the water 
column;
    [cir] The lowest bubble ring must be in contact with the substrate 
for the full circumference of the ring, and the weights attached to the 
bottom ring shall ensure 100 percent substrate contact. No parts of the 
ring or other objects shall prevent full substrate contact; and
    [cir] Air flow to the bubblers must be balanced around the 
circumference of the pile.
    Based on our evaluation of BNSF's planned measures, NMFS has 
determined that the required mitigation measures provide the means 
effecting the least practicable impact on the affected species or 
stocks and their habitat, paying particular attention to rookeries, 
mating grounds, and areas of similar significance.

Monitoring and Reporting

    In order to issue an IHA for an activity, section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth requirements pertaining to the 
monitoring and reporting of such taking. The MMPA implementing 
regulations at 50 CFR 216.104 (a)(13) indicate that requests for 
authorizations must include the suggested means of accomplishing the 
necessary monitoring and reporting that will result in increased 
knowledge of the species and of the level of taking or impacts on 
populations of marine mammals that are expected to be present in the 
action area. Effective reporting is critical both to compliance as well 
as ensuring that the most value is obtained from the required 
monitoring.
    Monitoring and reporting requirements prescribed by NMFS should 
contribute to improved understanding of one or more of the following:
     Occurrence of marine mammal species or stocks in the area 
in which take is anticipated (e.g., presence, abundance, distribution, 
density);
     Nature, scope, or context of likely marine mammal exposure 
to potential stressors/impacts (individual or cumulative, acute or 
chronic), through better understanding of: (1) Action or environment 
(e.g., source characterization, propagation, ambient noise); (2) 
affected species (e.g., life history, dive patterns); (3) co-occurrence 
of marine mammal species with the action; or (4) biological or 
behavioral context of exposure (e.g., age, calving or feeding areas);
     Individual marine mammal responses (behavioral or 
physiological) to acoustic stressors (acute, chronic, or cumulative), 
other stressors, or cumulative impacts from multiple stressors;
     How anticipated responses to stressors impact either: (1) 
Long-term fitness and survival of individual marine mammals; or (2) 
populations, species, or stocks;
     Effects on marine mammal habitat (e.g., marine mammal prey 
species, acoustic habitat, or other important physical components of 
marine mammal habitat); and
     Mitigation and monitoring effectiveness.

Visual Monitoring

    Marine mammal monitoring must be conducted in accordance with the 
Marine Mammal Monitoring Plan found in Appendix E in the application. 
Marine mammal monitoring during drilling, clipping, cutting, pile 
driving and removal must be conducted by NMFS-approved PSOs in a manner 
consistent with the following:
     Independent PSOs (i.e., not construction personnel) who 
have no other assigned tasks during monitoring periods must be used;
     At least one PSO must have prior experience performing the 
duties of a PSO during construction activity pursuant to a NMFS-issued 
incidental take authorization;
     Other PSOs may substitute other relevant experience, 
education (degree in biological science or related field), or training 
for prior experience performing the duties of a PSO during construction 
activity pursuant to a NMFS-issued incidental take authorization; and
     PSOs must be approved by NMFS prior to beginning any 
activity subject to this IHA.
    PSOs must have the following additional qualifications:
     Ability to conduct field observations and collect data 
according to assigned protocols;
     Experience or training in the field identification of 
marine mammals, including the identification of behaviors;
     Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations;
     Writing skills sufficient to prepare a report of 
observations including but not limited to the number and species of 
marine mammals observed; dates and times when in-water construction 
activities were conducted; dates, times, and reason for implementation 
of mitigation (or why mitigation was not implemented when required); 
and marine mammal behavior; and
     Ability to communicate orally, by radio or in person, with 
project personnel to provide real-time information on marine mammals 
observed in the area as necessary;
    A minimum of three PSOs located at positions designated in Figure 1 
and Figure 2 of the Marine Mammal Monitoring Plan found in Appendix E 
of the Application must monitor harassment zones during all in-water 
construction activities. One PSO would be stationed in close proximity 
to the construction site. A second PSO would be stationed at Bay 
Terrace Road which is located east of the Bridge 6.3 on the

[[Page 22517]]

southern side of the Ship Canal. This location would provide views of 
ensonified areas radiating into Shilshole Bay as well as waters east of 
the mouth of the Ship Canal. A third PSO would be located on the north 
side of the Ship Canal at the Northwest 60th Street Viewpoint west of 
Bridge 6.3. This location provides views westward towards the mouth of 
the Ship Canal. A fourth PSO must be on a boat positioned in Puget 
Sound when a wire saw is being utilized to monitor the extended Level B 
harassment zone associated with this equipment. A wire saw would be 
employed on approximately 6 in-water work days. If hydroacoustic 
monitoring results of diamond wire saw cutting activities show that the 
entirety of the Level B harassment zone may be viewed by from land-
based PSOs, then the PSO on the boat may not be deployed. All results 
from hydroacoustic monitoring, described in the next section, must be 
submitted to NMFS. NMFS must approve the removal of the boat-based PSO 
and modification of the new harassment isopleth.
    Monitoring will be conducted 30 minutes before, during, and 30 
minutes after drilling, clipping, cutting, pile driving/removal 
activities. In addition, observers shall record all incidents of marine 
mammal occurrence, regardless of distance from activity, and shall 
document any behavioral reactions in concert with distance from piles 
being driven or removed. Drilling, clipping, cutting, Pile driving 
activities include the time to install or remove a single pile or 
series of piles, as long as the time elapsed between uses of the 
drilling, clipping, cutting, pile driving equipment is no more than 30 
minutes.

Hydroacoustic Monitoring

    Hydroacoustic monitoring will be conducted during in-water pile-
driving and wire saw activities and recorded source levels will be 
compared to the reported sound levels employed as part of this 
application to determine harassment isopleths modeled in this 
application. Information about methods, data collection, and reporting 
are described in the Acoustic Monitoring Plan in Appendix F of the 
Application. The following representative subsets will be measured:
     A minimum of 15, 36-inch impact driven piles for the 
Project in the following subsets:
    1. A minimum of 5 piles towards the beginning of pile driving 
activity;
    2. A minimum of 5 piles towards the middle of pile driving 
activity;
    3. A minimum of 5 piles towards the latter pile driving activity.
     A minimum of 4, 48-inch drilled shafts oscillated for the 
Project in the following subsets:
    1. A minimum of 2 drilled shafts towards the beginning of the 
activity;
    2. A minimum of 2 drilled shafts towards the end of the activity.
     A minimum of 2 48-inch drilled shafts will be monitored 
when cut with a wire saw.

Reporting

    BNSF must submit its draft reports on all monitoring conducted 
under the IHAs within 90 calendar days of the completion of monitoring 
or 60 calendar days prior to the requested issuance of any subsequent 
IHA for construction activity at the same location, whichever comes 
first. A final report must be prepared and submitted within 30 calendar 
days following receipt of any NMFS comments on the draft report. If no 
comments are received from NMFS within 30 calendar days of receipt of 
the draft report, the report shall be considered. The report will 
include an overall description of work completed, a narrative regarding 
marine mammal sightings, and associated PSO data sheets. Specifically, 
the report must include:
     Dates and times (begin and end) of all marine mammal 
monitoring;
     Construction activities occurring during each daily 
observation period, including how many and what type of piles were 
driven or removed and by what method: Drilling, cutting, clipping, 
impact driving, and vibratory driving and removal ; duration of driving 
time for each pile (vibratory) and number of strikes per pile (impact 
driving);
     PSO locations during marine mammal monitoring;
     Environmental conditions during monitoring periods (at 
beginning and end of PSO shift and whenever conditions change 
significantly), including Beaufort sea state and any other relevant 
weather conditions including cloud cover, fog, sun glare, and overall 
visibility to the horizon, and estimated observable distance;
     Name of PSO who sighted the animal(s) and PSO location and 
activity at time of sighting;
     Time of sighting;
     Identification of the animal(s) (e.g., genus/species, 
lowest possible taxonomic level, or unidentified), PSO confidence in 
identification, and the composition of the group if there is a mix of 
species;
     Distance and location of each observed marine mammal 
relative to the pile being driven for each sighting;
     Estimated number of animals (min/max/best estimate);
     Estimated number of animals by cohort (adults, juveniles, 
neonates, group composition, etc.);
     Animal's closest point of approach and estimated time 
spent within the harassment zone;
     Description of any marine mammal behavioral observations 
(e.g., observed behaviors such as feeding or traveling), including an 
assessment of behavioral responses thought to have resulted from the 
activity (e.g., no response or changes in behavioral state such as 
ceasing feeding, changing direction, flushing, or breaching);
     Number of marine mammals detected within the harassment 
zones, by species; and
     Detailed information about implementation of any 
mitigation (e.g., shutdowns and delays), a description of specific 
actions that ensued, and resulting changes in behavior of the 
animal(s), if any.
    The acoustic monitoring report must contain the informational 
elements described in the Acoustic Monitoring Plan and, at minimum, 
must include:
     Hydrophone equipment and methods: recording device, 
sampling rate, distance (m) from the pile where recordings were made; 
depth of water and recording device(s);
     Type and size of pile being driven or cut, substrate type, 
method of driving or cutting during recordings (e.g., hammer model and 
energy), and total pile driving or cutting duration;
     Whether a sound attenuation device is used and, if so, a 
detailed description of the device used and the duration of its use per 
pile;
     For impact pile driving (per pile): Number of strikes; 
depth of substrate to penetrate; pulse duration and mean, median, and 
maximum sound levels (dB re: 1 [micro]Pa): Root mean square sound 
pressure level (SPLrms); cumulative sound exposure level (SELcum), peak 
sound pressure level (SPLpeak), and single-strike sound exposure level 
(SELs-s);
     For wire saw cutting (per pile): Duration of driving per 
pile; mean, median, and maximum sound levels (dB re: 1 [micro]Pa): Root 
mean square sound pressure level (SPLrms), cumulative sound exposure 
level (SELcum) (and timeframe over which the sound is averaged); and
     One-third octave band spectrum and power spectral density 
plot.
    In the event that personnel involved in the construction activities 
discover an injured or dead marine mammal, the IHA-holder shall report 
the incident to the Office of Protected Resources (OPR) (301-427-8401), 
NMFS and to the West Coast Region Stranding Hotline (866-

[[Page 22518]]

767-6114) as soon as feasible. If the death or injury was clearly 
caused by the specified activity, the IHA-holder must immediately cease 
the specified activities until NMFS is able to review the circumstances 
of the incident and determine what, if any, additional measures are 
appropriate to ensure compliance with the terms of the IHA. The IHA-
holder must not resume their activities until notified by NMFS.
    The report must include the following information:
    i. Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
    ii. Species identification (if known) or description of the 
animal(s) involved;
    iii. Condition of the animal(s) (including carcass condition if the 
animal is dead);
    iv. Observed behaviors of the animal(s), if alive;
    v. If available, photographs or video footage of the animal(s); and
    vi. General circumstances under which the animal was discovered.

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 of the species listed in Table 13, given that many of 
the anticipated effects of this project on different marine mammal 
stocks are expected to be relatively similar in nature. Where there are 
meaningful differences between species or stocks in anticipated 
individual responses to activities, impact of expected take on the 
population due to differences in population status, or impacts on 
habitat, they are described independently in the analysis below, such 
as for the potential repeated and prolonged exposure of habituated 
harbor seals that feed on salmonids traversing through the lock system. 
The analysis below applies to both the Year 1 and Year 2 authorized 
IHAs, except where noted otherwise.
    Drilling, clipping, cutting, Pile driving and removal activities 
associated with the project, as outlined previously, have the potential 
to disturb or displace marine mammals. Specifically, the specified 
activities may result in take, in the form of Level A harassment and 
Level B harassment from underwater sounds generated by drilling, 
clipping, cutting, pile driving and removal. Potential takes could 
occur if marine mammals are present in zones ensonified above the 
thresholds for Level A or Level B harassment, identified above, while 
activities are underway.
    The nature of the drilling, clipping, cutting, pile driving project 
precludes the likelihood of serious injury or mortality. The mitigation 
is expected to ensure that no Level A harassment occurs to any species 
except harbor seal. The nature of the estimated takes anticipated to 
occur are similar among all species and similar in Year 1 and Year 2, 
other than the potential Level A harassment take of harbor seal in Year 
1, described further below and the likely comparatively higher number 
of repeated takes of some small number of harbor seals by Level B 
harassment during both Year 1 and Year 2.
    For all species other than harbor seal, take would be limited to 
Level B harassment (behavioral disturbance and TTS) only. Effects on 
individuals that are taken by Level B harassment, on the basis of 
reports in the literature as well as monitoring from other similar 
activities, will likely include reactions such as increased swimming 
speeds, increased surfacing time, or decreased foraging (if such 
activity were occurring). Marine mammals present in the vicinity of the 
action area and taken by Level B harassment are most likely to move 
away from and avoid the area of elevated noise levels during in-water 
construction activities. The project site itself is located along a 
highly developed waterfront with high amounts of vessel traffic and, 
therefore, we expect that most animals disturbed by project sound would 
simply avoid the area and use more-preferred habitats. These short-term 
behavioral effects are not expected to affect marine mammals' fitness, 
survival, and reproduction due to the limited geographic area that 
would be affected in comparison to the much larger habitat for marine 
mammals in the Puget Sound. Harbor seals that are habituated to in-
water construction noise could be exposed for 5.4 hours per day for up 
to 10 consecutive days during impact driving activities in Year 1 only. 
These animals would likely remain in close proximity to the locks and 
may be exposed to enough accumulated energy to result in TTS or PTS 
(described below). Longer duration exposure could result in TTS in some 
cases if exposures occur within the Level B TTS zone. As discussed 
earlier in this document, TTS is a temporary loss of hearing 
sensitivity when exposed to loud sound, and the hearing threshold is 
expected to recover completely within minutes to hours. Any behavioral 
effects of repeated or long duration exposures are not expected to 
negatively impact survival or reproductive success of any individuals. 
Similarly, given that the exposure to these individuals is not expected 
to exceed 10 consecutive days for 5.4 or fewer hours at a time for any 
individual, any limited energetic impacts from the interruption of 
foraging or other important behaviors are not expected to affect the 
reproductive success of any individual harbor seals.
    In addition to the expected effects resulting from authorized Level 
B harassment, we anticipate that a limited number of habituated harbor 
seals (20) may sustain some Level A harassment in the form of auditory 
injury during 10 days of impact driving planned for Year 1 only. 
However, any animals that experience PTS would likely only receive 
slight PTS, i.e. minor degradation of hearing capabilities within 
regions of hearing that align most completely with the frequency range 
of the energy produced by pile driving (i.e., the low-frequency region 
below 2kHz), not severe hearing impairment or impairment in the reigns 
of greatest hearing sensitivity. If hearing impairment does occur, it 
is most likely that the affected animal would lose a

[[Page 22519]]

few dBs in its hearing sensitivity, which in most cases, is not likely 
to meaningfully affect its ability to forage and communicate with 
conspecifics. These takes by Level A harassment (i.e., a small degree 
of PTS) of habituated harbor seals are not expected to accrue in a 
manner that would affect the reproductive success or survival of any 
individuals, much less result in adverse impacts on the species or 
stock. As described above, we expect that marine mammals would be 
likely to move away from a sound source that represents an aversive 
stimulus, especially at levels that would be expected to result in PTS, 
given sufficient notice through use of soft start.
    The project is also not expected to have significant adverse 
effects on affected marine mammals' habitats. The project activities 
will not modify existing marine mammal habitat for a significant amount 
of time. The activities may cause some fish to leave the area of 
disturbance, thus temporarily impacting marine mammals' foraging 
opportunities in a limited portion of the foraging range; 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.
    Portions of the southern resident killer whale range are within the 
project area and the entire Puget Sound is designated as critical 
habitat for these whales under the ESA. However, BNSF would be required 
to shut down and suspend pile driving or pile removal activities when 
this stock is detected in the vicinity of the project area. We 
anticipate that take of southern resident killer whale would be 
avoided. There are no other known important areas for other marine 
mammals, such as feeding or pupping, areas.
    In summary and as described above, the following factors primarily 
support our determination that the impacts resulting from this activity 
are not expected to adversely affect the species or stock through 
effects on annual rates of recruitment or survival:
     No mortality or serious injury is anticipated or 
authorized.
     For all species except harbor seal and only during Year 1, 
no Level A harassment is anticipated or authorized.
     The Level A harassment exposures to habituated harbor 
seals in Year 1 only are anticipated to result in slight PTS, within 
the lower frequencies associated with impact pile driving.
     Though a small number of habituated harbor seals will 
accrue Level B harassment in the form of TTS from repeated days of 
exposure, hearing thresholds are expected to completely recover within 
minutes to hours.
     Anticipated effects of Level B harassment in the form of 
behavioral modification would be temporary.
     Although a small portion of the southern resident killer 
whale critical habitat is within the project area, strict mitigation 
measures such as implementing shutdown measures and suspending pile 
driving are expected to avoid take of this stock. No other important 
habitat for marine mammals exist in the vicinity of the project area.
     We do not expect significant or long-term negative effects 
to marine mammal habitat.
    Year 1 IHA--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 required 
monitoring and mitigation measures, NMFS finds that the total marine 
mammal take from BNSF's construction activities will have a negligible 
impact on all affected marine mammal species or stocks.
    Year 2 IHA--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 required 
monitoring and mitigation measures, NMFS finds that the total marine 
mammal take from BNSF's construction activities will have a negligible 
impact on all affected marine mammal species or stocks.

Small Numbers

    As noted above, only small numbers of incidental take may be 
authorized under sections 101(a)(5)(A) and (D) of the MMPA for 
specified activities other than military readiness activities. The MMPA 
does not define small numbers and so, in practice, where estimated 
numbers are available, NMFS compares the number of individuals taken to 
the most appropriate estimation of abundance of the relevant species or 
stock in our determination of whether an authorization is limited to 
small numbers of marine mammals. When the predicted number of 
individuals to be taken is fewer than one third of the species or stock 
abundance, the take is considered to be of small numbers. Additionally, 
other qualitative factors may be considered in the analysis, such as 
the temporal or spatial scale of the activities.
    The amount of take NMFS has authorized is below one third of the 
estimated stock abundance for all species during both Year 1 and Year 
2. The authorized take of individuals during Year 1 is less than 32.6 
percent for harbor seals and less than 1 percent for all other 
authorized species. During year 2 the authorized take of individuals is 
less than 5.2 percent of the abundance of the affected species or stock 
as shown in Table 13. Note that harbor seal take during Year 1 likely 
includes multiple repeated takes of some small group of individuals. 
Similarly, for all other authorized species, the authorized take 
numbers probably represent conservative estimates because they assume 
all takes are of different individual animals, which is unlikely to be 
the case. Some individuals may return multiple times in a day, but PSOs 
would count them as separate takes if they cannot be individually 
identified.
    Year 1 IHA--Based on the analysis contained herein of the activity 
(including the 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 in Year 1 of the project.
    Year 2 IHA--Based on the analysis contained herein of the activity 
(including the 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 in Year 2 of the project.

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

    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 whenever we authorize take for endangered or 
threatened species.
    No incidental take of ESA-listed species is authorized or expected 
to

[[Page 22520]]

result from this activity. Therefore, NMFS has determined that formal 
consultation under section 7 of the ESA is not required for this 
action.

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must review our action (i.e., the issuance of an IHA) with respect 
to potential impacts on the human environment.
    This action is consistent with categories of activities identified 
in Categorical Exclusion B4 (IHAs with no anticipated serious injury or 
mortality) of the Companion Manual for NOAA Administrative Order 216-
6A, which do not individually or cumulatively have the potential for 
significant impacts on the quality of the human environment and for 
which we have not identified any extraordinary circumstances that would 
preclude this categorical exclusion. Accordingly, NMFS has determined 
that the issuance of the IHAs qualifies to be categorically excluded 
from further NEPA review

Authorizations

    As a result of these determinations, NMFS has issued two distinct 
and consecutive one-year IHAs to BNSF for construction associated with 
the Railway Bridge 0050-0006.3 Heavy Maintenance Project in King 
County, Washington from July 16, 2022 to July 15, 2023 (Year 1) and 
from July 16, 2023 to July 15, 2024 (Year 2) provided the previously 
mentioned mitigation, monitoring, and reporting requirements are 
incorporated.

    Dated: April 12, 2022.
Catherine Marzin,
Deputy Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2022-08135 Filed 4-14-22; 8:45 am]
BILLING CODE 3510-22-P