[Federal Register Volume 82, Number 98 (Tuesday, May 23, 2017)]
[Notices]
[Pages 23534-23550]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-10536]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XE988


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to a Dock Replacement Project in 
Unalaska, Alaska

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

ACTION: Notice; issuance of an incidental harassment authorization.

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SUMMARY: In accordance with regulations implementing the Marine Mammal 
Protection Act (MMPA) as amended, notification is hereby given that 
NMFS has issued an Incidental Harassment Authorization (IHA) to the 
City of Unalaska (COU) to incidentally harass, by Level B harassment 
only, marine mammals during construction activities associated with a 
dock expansion project at the existing Unalaska Marine Center (UMC) 
Dock in Unalaska, Alaska.

DATES: Effective April 28, 2017 through April 27, 2018.

FOR FURTHER INFORMATION CONTACT: Jolie Harrison, Office of Protected 
Resources, NMFS, (301) 427-8401.

SUPPLEMENTARY INFORMATION: 

Availability

    An electronic copy of the COU's application and supporting 
documents, as well as a list of the references cited in this document, 
may be obtained by visiting the Internet at: http://www.nmfs.noaa.gov/pr/permits/incidental/construction.htm. In case of problems accessing 
these documents, please call the contact listed under FOR FURTHER 
INFORMATION CONTACT.

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct the Secretary of Commerce to allow, upon request, the 
incidental, but not intentional, taking of small numbers of marine 
mammals by U.S. citizens who engage in a specified activity (other than 
commercial fishing) within a specified geographical region if certain 
findings are made and either regulations are issued or, if the taking 
is limited to harassment, a notice of a proposed authorization is 
provided to the public for review.
    An authorization for incidental takings shall be granted if NMFS 
finds that the taking will have a negligible impact on the species or 
stock(s), will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for subsistence uses (where 
relevant), and if the permissible methods of taking and requirements 
pertaining to the mitigation, monitoring and reporting of such takings 
are set forth. NMFS has defined ``negligible impact'' in 50 CFR 216.103 
as ``an impact resulting from the specified activity that cannot be 
reasonably expected to, and is not reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival.''
    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as: any act of pursuit, torment, or 
annoyance which (i) has the potential to injure a marine mammal or 
marine mammal stock in the wild (Level A harassment); or (ii) has the 
potential to disturb a marine mammal or marine mammal stock in the wild 
by causing disruption of behavioral patterns, including, but not 
limited to, migration, breathing, nursing, breeding,

[[Page 23535]]

feeding, or sheltering (Level B harassment).

Summary of Request

    On March 22, 2016, we received a request from the COU for 
authorization to take marine mammals incidental to pile driving and 
pile removal associated with construction activities that would expand 
the existing UMC Dock in Dutch Harbor in the City of Unalaska, on 
Amaknak Island, Alaska. The COU submitted a revised version of the 
request on July 30, 2016, which was deemed adequate and complete. In 
August 2016, NMFS released its Technical Guidance for Assessing the 
Effects of Anthropogenic Sound on Marine Mammal Hearing (the Guidance, 
available at http://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm) 
which provides technical guidance for assessing the effects of 
anthropogenic sound on the hearing of marine mammal species under the 
jurisdiction of NMFS. The Guidance establishes new thresholds for 
predicting auditory injury, which equates to Level A harassment under 
the MMPA. The COU was able to update relevant portions of their 
application to incorporate re-calculated Level A harassment zones for 
vibratory and impact pile driving activities based on the updated 
acoustic thresholds described in the Guidance. The results of those 
calculations (i.e., revised distances to Level A harassment thresholds) 
were provided to NMFS by the COU in September 2016 and were included in 
the proposed IHA. NMFS published a notice in the Federal Register 
making preliminary determinations and proposing to issue an IHA on 
November 10, 2016 (81 FR 78969). The notice initiated a 30-day comment 
period.
    The COU proposes to demolish portions of the existing UMC dock and 
install a new dock between April 2017 and November 2017. The use of 
both vibratory and impact pile driving during pile removal and 
installation is expected to produce underwater sound at levels that 
have the potential to result in behavioral harassment of marine 
mammals. Species with the expected potential to be present during all 
or a portion of the in-water work window include Steller sea lion 
(Eumetopias jubatus), harbor seal (Phoca vitulina), humpback whale 
(Megaptera novaeangliae), and killer whale (Orcinus orca).
    To account for potential unexpected delay in project time frame, 
the IHA issued to COU covers the period from April 28, 2017, to April 
27, 2018, based on impact analysis.

Description of the Specified Activity

Overview

    In order to meet the increasing needs of the international shipping 
industry and increase vessel berthing capacity, a substantial upgrade 
of aging UMC facilities is necessary. The proposed project will replace 
the existing pile supported docks located at UMC Dock Positions III and 
IV with a modern high-capacity sheet pile bulkhead dock that extends 
from the existing bulkhead dock at Position V to the U.S. Coast Guard 
(USCG) Dock.
    COU port operations saw numerous factory trawler offloads occurring 
at Dock Positions III and IV in 2013. These operations require more 
length at the face of the dock and greater uplands area than is 
available with the current infrastructure. The existing pile-supported 
docks are aging structures in shallower water that no longer meet the 
needs of the Port and require increasing levels of maintenance and 
monitoring costs. Both docks are also severely constrained by the 
limited uplands area available for offloading and loading operations.
    Dock Position III is a timber pile-supported dock with 
approximately 160 feet of dock face that was constructed in the 1960's 
by the U.S. Army Corps of Engineers (USACE). This dock has been used 
for the Alaska Marine Highway System, vessel moorage, and factory 
trawler offloads. However, use of this structure is severely limited 
due to the low load-carrying capacity of the dock. The bullrails, deck 
surface, and bollards have deteriorated with age and the entire 
structure is in need of replacement or extensive renovations.
    Dock Position IV is a steel-pile-supported, concrete deck structure 
with an approximate length of 200 feet that was constructed in the 
1980s by the State of Alaska. Similar to Dock Position III, use of this 
dock is limited due to the low load capacity of the structure. Erosion 
has damaged an abutment underneath the dock, which is very difficult to 
repair and has the potential for further damage to adjacent portions of 
the dock.
    The dock face of Dock Positions III and IV does not align with the 
larger sections of the UMC facility, significantly limiting overall 
usable moorage space. The proposed project aligns the new dock 
structures with the adjacent facilities, eliminates two angle breaks, 
provides substantially more usable moorage, and provides much deeper 
water at the dock face. The sheet pile dock will encompass the area 
between Dock Position V and the adjacent USCG Dock, providing maximum 
use of the available berthing area and upland storage space. The new 
dock alignment will allow larger, deeper vessels as well as 
simultaneous use of the other UMC facilities.

Dates and Duration

    In-water and over-water construction of Phase 1 (all sheet pile 
installation, all in-water pipe pile installation, most upland pipe 
pile installation, and fill placement) is planned to occur between 
approximately April 1, 2017 and November 1, 2017. Phase 2 is planned to 
occur between approximately May 1, 2018 and October 1, 2018. Some of 
the upland pipe pile for utilities may be driven in upland fill away 
from the dock face during Phase 2. The COU proposes to use the 
following general construction sequence, subject to adjustment by the 
construction contractor's means and methods:
    Construction Phase 1 (2017):
     Mobilization of equipment and demolition of the existing 
dock Positions III and IV and removal of any existing riprap/
obstructions (April-May 2017).
     Development of the quarry for materials.
     Installation (and later removal) of temporary support 
piles for contractor's template structures and barge support.
     Installation of the new sheet pile bulkhead dock. This 
includes driving sheet piles, placing fill within the cell to grade, 
and compaction of fill.
     Installation of fender and platform support piles in the 
water adjacent to the dock and miscellaneous support piles within the 
completed sheet pile cells.
     Installation of pre-assembled fender systems (energy 
absorbers, sleeve piles, steel framing, and fender panels).
     Installation of the crane support piles.
     Installation of temporary utilities and gravel surface to 
provide functional dock capability for the 2017/2018 season.
    Construction Phase 2 (2018):
     Installation of concrete grade beam for crane rails, 
utility vaults, and dock surfacing.
     Installation of electrical, sewer, fuel, water, and storm 
drainage utilities.
    Pile removal and pile driving is expected to occur between April 1 
and November 1, 2017. In the summer months (April-September), 12-hour 
workdays in extended daylight will likely be used. In winter months 
(October-March), shorter 8-hour to 10-hour workdays in available 
daylight will likely be achievable. Work windows may be extended or 
shortened if or when electrical lighting is used. The

[[Page 23536]]

daily construction window for pile driving or removal will begin no 
sooner than 30 minutes after sunrise to allow for initial marine mammal 
monitoring to take place, and will end 30 minutes before sunset to 
allow for pre-activity monitoring. It is assumed that sound associated 
with the pile driving and removal activities will be put into the water 
approximately 50 percent of the total estimated project duration of 245 
days (2,940 hours for 12-hour workdays). The remaining 50 percent of 
the project duration will be spent on activities that provide distinct 
periods without noise from pile driving or drilling such as installing 
templates and braces, moving equipment, threading sheet piles, pulling 
piles (without vibration), etc. During this time, a much smaller area 
will be monitored to ensure that animals are not injured by equipment 
or materials.

Specific Geographic Region

    The UMC Dock is located in Dutch Harbor in the City of Unalaska, on 
Amaknak Island, Alaska (see Figure 5 of the application). Dutch Harbor 
is separated from the adjacent Iliuliuk Bay by a spit. The dock is 
located in Section 35, Township 72 South, Range 118 West, of the Seward 
Meridian. Tidelands in this vicinity are owned by the COU. Some of the 
adjacent uplands are owned by the COU and some are leased by the COU 
from Ounalashka Corporation. Adjacent infrastructure includes Ballyhoo 
Road and the Latitude 54 Building in which the COU Department of Ports 
and Harbors offices and facilities are currently housed. Neighboring 
docks include the USCG Dock and the existing UMC OCSP dock positions. 
Other marine facilities within Dutch Harbor include Delta Western Fuel, 
the Resolve-Magone Dock, North Pacific Fuel, the Kloosterboer Dock, and 
the COU's Light Cargo Dock and Spit Dock facilities, as shown in Figure 
5 of the application. APL Limited is located within Iliuliuk Bay, and 
the entrance channel to Iliuliuk Harbor is south of Dutch Harbor.

Detailed Description of Activities

    The COU proposes to install an OPEN CELL SHEET PILETM 
(OCSP) dock at UMC Dock Position III and IV, replacing the existing 
pile-supported structure and providing a smooth transition between the 
UMC facility and the USCG dock. The OCSP dock will be constructed of 
PS31 flat sheet piles (web thickness of 0.5 inches and width between 
interlocks of 19.69 inches). In order to replace the existing timber 
pile-supported dock, the dock construction would include installation 
of the following:
     Approximately forty (40) 30-inch diameter steel fender and 
transition platform support piles;
     Approximately thirty (30) 30-inch diameter miscellaneous 
steel support piles
     Approximately one hundred fifty (150) 30-inch diameter 
steel crane rail support piles (approximately 25 of which are above the 
high tide line (HTL));
     Approximately one hundred fifty (150) 18-inch steel piles 
(H or round) used for temporary support of the sheet pile during 
construction (to be removed prior to completion);
     Approximately 1,800 PS31 flat sheet piles (approximately 
100 of which are above the high tide line (HTL)); and
     Placement of approximately 110,000 cubic yards of clean 
fill.
    The anticipated project quantities are shown in Table 1.
    Concurrent with the dock construction, a material source will be 
developed in the hillside adjacent to Dock Position VII. The quarry 
will provide material for dock fill and other future projects, and the 
cleared area will be used for COU port offices and associated parking 
after the quarry is completed. The quarry will be developed through 
blasting benches in the rock face, with each bench being approximately 
25 feet high, with the total height being approximately 125 feet. 
Quarry materials will be transported the short distance to the adjacent 
project site using heavy equipment.

                                        Table 1--Total Project Quantities
----------------------------------------------------------------------------------------------------------------
                                                                    Below mean      Below high
                                                                    high water       tide line
                Item                   Size and type, location     (MHW) (El. =    (HTL) (El. =        Total
                                                                       3.4)            4.7)
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Surface Area of Dock (Acres).......  ...........................             2.1             2.3             3.1
Surface Area of Water Filled         ...........................             2.1             2.8             2.8
 (Acres).
Gravel Fill (Cubic Yards)..........  Clean Fill; Within dock....          74,000          80,000         110,000
Piles to be Removed (Each).........  Steel......................             195             195             195
                                     Timber.....................              55              55              55
Estimated Temporary Piles (Each)...  18'' Steel Pile; Within                 150             150             150
                                      dock.
Steel Piles--Fender and Platform     30'' Steel; In front of                  40              40              40
 Support (Each).                      bulkhead.
Miscellaneous Support Piles (Each).  30'' Steel; Within dock                  30              30              30
                                      (not in-water).
Crane Rail Support Piles (Each)....  30'' Steel; Within dock                 125             125             150
                                      (not in-water).
Proposed Sheet Piles (Each)........  PS31 Sheet Pile; Dock face.           1,400           1,700           1,800
----------------------------------------------------------------------------------------------------------------

    The existing structure will be demolished by removing the concrete 
deck, steel superstructure, and attached appurtenances and structures 
and then extracting the existing steel support piles with a vibratory 
hammer. Sheet pile will also be installed with a vibratory hammer. Pile 
driving may occur from shore or from a stationary barge platform, 
depending on the Contractor's selected methods. After cells are 
completely enclosed, they will be incrementally filled with clean 
material using bulldozers and wheel loaders. Fill will be placed 
primarily from shore, but some may be placed from the barge if needed. 
Fill will be compacted using vibratory compaction methods, described 
below. After all the sheet piles are installed and the cells are filled 
and compacted, fender piles, crane rail piles, mooring cleats, concrete 
surfacing, and other appurtenances will be installed.
    As described, the project requires the removal and installation of 
various types and sizes of piles with the use of a vibratory hammer and 
impact hammer. These activities have the potential to result in Level B 
harassment (behavioral disruption) only, as a monitoring plan will be 
implemented to reduce the potential for exposure to Level A harassment 
(harassment resulting in injury). The rest of the in-water components 
of the project are

[[Page 23537]]

provided here for completeness. Note that many of the support piles 
will be installed to an elevation below MHW or HTL; however, they will 
be installed within the enclosed fill of the sheet pile dock rather 
than in the water.
    Utilities will be installed during Phase II, and include addition/
extension of water, sewer, fuel, electrical, and storm drain. 
Authorization to construct the sewer and storm drain extension, as well 
as a letter of non-objection for the storm drain, will be obtained from 
the State of Alaska Department of Environmental Conservation (ADEC).
    A detailed description of the proposed project is provided in the 
Federal Register notice for the proposed IHA (81 FR 78969; November 10, 
2016). Since that time, no changes have been made to the planned 
project activities. Therefore, a detailed description is not provided 
here. Please refer to that Federal Register notice for the description 
of the specific activity.

Comments and Responses

    A notice of NMFS's proposal to issue an IHA to the City was 
published in the Federal Register on November 10, 2016 (81 FR 78969). 
That notice described, in detail, the COU's activity, the marine mammal 
species that may be affected by the activity, and the anticipated 
effects on marine mammals. During the 30-day public comment period, 
NMFS received comments from the Marine Mammal Commission (Commission). 
Specific comments and responses are provided below. Comments are also 
posted at http://www.nmfs.noaa.gov/pr/permits/incidental/.
    Comment 1: The Commission recommends that NMFS (1) compile all in-
situ source level pile-driving and pile-removal measurements from past 
and future projects in a central database, (2) require each action 
proponent to specify the sediment composition, water depth (in terms of 
hydrophone placement and bathymetry), duration over which the pressure 
was averaged for SPLrms metrics, and median values in all 
future hydroacoustic monitoring reports, (3) ensure consistency 
regarding integration timeframes used for SPLrms 
measurements (e.g., 1-second averages, maximum over 10 seconds, or 
maximum over 30 seconds) in all future hydroacoustic monitoring 
reports, (4) require each action proponent to use median proxy source 
levels from all relevant sources when in-situ data are unavailable, and 
(5) require each action proponent to use the upper 90th percentile 
rather than the best-fit regression to inform the range to effects in 
all future hydroacoustic monitoring reports.
    Response: NMFS understands the importance of taking a consistent 
approach when disseminating data for impact analyses, and is currently 
working on a guidance on in-water pile driving assessment, which will 
be supplemented by a compilation of in-situ source levels from pile 
driving and pile removal measurements from the past. The guidance will 
also include language that requires future sound source verifications 
(SSVs) to include information on sediment composition and water depth. 
Many of the standardized practices for SSVs such as hydrophone depth 
and integration time for impact and vibratory sound sources are 
provided in NMFS 2012 pile driving guidance. NMFS will refer applicants 
to this guidance in the future, and will also refer to these documents 
in the guidance that is being developed.
    While NMFS is striving to achieve consistency in marine mammal 
impact analyses, including developing standard and acceptable 
methodologies and metrics for measuring and quantifying underwater 
noise sources, considerations are also given to action proponents with 
limited resources. In the case of data treatment whether percentile or 
regression to be used would depend on how measurements are conducted 
and how many data points an action proponent collected. For example, if 
an SSV is conducted using a shipboard hydrophone that collected 
acoustic data at various distances from the source, the amount of data 
at each location may be limited, not necessarily allowing us to perform 
a statistical treatment to obtain the percentile. Therefore, NMFS 
accepts a single data point at the received distance, or a distance 
derived using best-fit regression from a set of data that is available.
    Comment 2: The Commission recommends that NMFS require each action 
proponent to (1) use a consistent source level reduction factor when 
sound attenuation devices would be used during impact pile driving and 
in-situ data are unavailable and (2) conduct bubble curtain testing 
(for air pressure and flow prior to impact hammer use) and place the 
bubble curtain device on the substrate in all relevant incidental take 
authorizations.
    Response: The effectiveness of noise attenuation devices often 
depends on oceanographic conditions such as currents and tides, thus 
should be evaluated in a case by case fashion. For example, for pile 
driving activities being conducted in Puget Sound where local currents 
are strong, NMFS worked with the action proponent and recommend 0 dB 
reduction when calculating ensonified zones, while in other locations 
it has been shown in the past that an attenuation of 10 dB or more can 
be achieved. Regarding the second point from the Commission's comment, 
NMFS believes that the requirement for bubble curtain testing and 
design should also be considered in a case by case situation, as some 
of the action proponents may have limited resources to conduct such 
test or design a bubble curtain device that meets certain 
specifications.
    In this case, no noise reduction is included in the calculation 
because the project proponent is not required to implement bubble 
curtain.
    Comment 3: The Commission recommends that NMFS require each action 
proponent to implement a 100- rather than 50-msec pulse duration 
consistently when using NMFS's user spreadsheet and SPLrms-
based source levels to determine ranges to the various Level A 
harassment SELcum thresholds for impact pile driving.
    Response: NMFS agrees with the Commission and will require each 
action proponent to implement a 100-msec pulse duration when using 
NMFS's optional spreadsheet and SPLrms-based source level to 
determine ranges to Level A harassment zones. Consequently, 100-msec is 
the pulse duration we used for calculating Level A ensonified zones.
    Comment 4: The Commission recommends that NMFS specify whether 
source levels based on SPLrms or SELs-s are more 
appropriate for action proponents to use when both are available and 
require each action proponent to use that metric consistently to 
determine the ranges to the various Level A harassment 
SELcum thresholds.
    Response: NMFS considers SELs-s provides a more accurate 
metric to calculate Level A harassment SELcum when using 
NMFS optional spread. Therefore, NMFS recommended action proponents to 
use that metric when both SPLrms and SELs-s are 
available. In the case of issuance an IHA to COU, SELs-s 
metric was used.

Description of Marine Mammals in the Area of the Specified Activity

    Marine waters near Unalaska Island support many species of marine 
mammals, including pinnipeds and cetaceans; however, the number of 
species regularly occurring within Dutch Harbor, including near the 
project location is limited due to the high volume of vessel traffic in 
and around the harbor. Due to this, Steller sea lion, harbor seal, 
humpback whale, and killer whale are the only species within NMFS

[[Page 23538]]

jurisdiction that are being included in the COA's IHA request. 
Sightings of other marine mammals within Dutch Harbor are extremely 
rare, and therefore, no further descriptions of the other marine 
mammals were included in the COA's application or in the notice of 
proposed authorization.
    We have reviewed COA's species descriptions--which summarize 
available information regarding status and trends, distribution and 
habitat preferences, behavior and life history, and auditory 
capabilities of the potentially affected species--for accuracy and 
completeness and refer the reader to Sections 3 and 4 of the 
application. Please also refer to NMFS' Web site (www.nmfs.noaa.gov/pr/species/mammals/) for generalized species accounts.
    Table 2 lists the marine mammal species with the potential for 
occurrence in the vicinity of the project during the project timeframe 
and summarizes key information regarding stock status and abundance. A 
detailed description of the species likely to be affected by the 
project, including brief introductions to the species and relevant 
stocks as well as available information regarding population trends and 
threats, and information regarding local occurrence, were provided in 
the Federal Register notice for the proposed IHA (81 FR 78969; November 
10, 2016). Since that time, we are not aware of any changes in the 
status of these species and stocks; therefore, detailed descriptions 
are not provided here. Please refer to that Federal Register notice for 
these descriptions. Please also refer to NMFS' Web site 
(www.nmfs.noaa.gov/pr/species/mammals/) for generalized species 
accounts.

                                   Table 2--Marine Mammals Potentially Present in the Vicinity of the Project Location
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                  Occurrence in/near
             Species                     Stock             MMPA status           ESA status            project            Seasonality        Abundance
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor seal (Phoca vitulina       Aleutian Islands...  Protected..........  ...................  Common.............  Year-round........           5,772
 richardsi).
Steller sea lion (Eumetopias      Western Distinct     Depleted, Strategic  Endangered.........  Common.............  Year-round........          49,497
 jubatus).                         Population Segment
                                   (DPS).
Killer whale (Orcinus orca).....  Eastern North        Protected..........  ...................  Unknown............  Summer, Fall......           2,347
                                   Pacific, Alaska
                                   Resident.
Killer whale (Orcinus orca).....  Gulf of Alaska,      Protected..........  ...................  Unknown............  Year-round........             587
                                   Aleutian Islands,
                                   and Bering Sea
                                   Transient.
Humpback whale (Megaptera         Central North        Depleted, Strategic  n/a *..............  Seasonal...........  Summer............          10,103
 novaeangliae).                    Pacific.
Humpback whale (Megaptera         Western North        Depleted, Strategic  n/a *..............  Seasonal...........  Summer............           1,107
 novaeangliae).                    Pacific.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* The newly defined DPSs (81 FR 62259) do not currently align with the stocks under the MMPA.

Potential Effects of the Specified Activity on Marine Mammals

    The effects of underwater noise from construction activities for 
the project have the potential to result in behavioral harassment of 
marine mammals in the vicinity of the action area. The Federal Register 
notice for the proposed IHA (81 FR 78969; November 10, 2016) included a 
discussion of the effects of anthropogenic noise on marine mammals, 
therefore that information is not repeated here. Please refer to the 
Federal Register notice for that information.

Effects on Marine Mammal Habitat

    The proposed activities at Dutch Harbor would not result in 
permanent impacts to habitats used directly by marine mammals, such as 
haul-out sites, but may have potential short-term impacts to food 
sources such as forage fish and salmonids. There are no rookeries or 
haulout sites within the modeled zone of influence for impact or 
vibratory pile driving associated with the project, or ocean bottom 
structure of significant biological importance to marine mammals that 
may be present in the waters in the vicinity of the project area. The 
project location receives heavy use by vessel moorage and factory 
trawler offloads, and experiences frequent vessel traffic because of 
these activities, thus the area is already relatively industrialized 
and not a pristine habitat for marine mammals. As such, the main impact 
associated with the proposed activity would be temporarily elevated 
sound levels and the associated direct effects on marine mammals, as 
discussed previously in this document. The most likely impact to marine 
mammal habitat occurs from pile driving effects on likely marine mammal 
prey (i.e., fish) near the project location, and minor impacts to the 
immediate substrate during installation and removal of piles during the 
dock construction project.
    The potential effects on marine mammal habitat are discussed in 
detail in the Federal Register notice for the proposed IHA (81 FR 
78969; November 10, 2016), therefore that information is not repeated 
here; please refer to that Federal Register notice for that 
information.

Mitigation

    In order to issue an IHA under section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to such 
activity, and other means of effecting the least practicable impact on 
such species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of such species or stock for taking for certain 
subsistence uses.
    The COU's calculation of the Level A harassment zones utilized the 
methods presented in Appendix D of NMFS' Technical Guidance for 
Assessing the Effects of Anthropogenic Sound on Marine Mammal Hearing 
(the Guidance, available at http://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm), and the

[[Page 23539]]

accompanying User Spreadsheet.\1\ The Guidance provides updated PTS 
onset thresholds using the cumulative SEL (SELcum) metric, 
which incorporates marine mammal auditory weighting functions, to 
identify the received levels, or acoustic thresholds, at which 
individual marine mammals are predicted to experience changes in their 
hearing sensitivity for acute, incidental exposure to all underwater 
anthropogenic sound sources. The Guidance (Appendix D) and its 
companion User Spreadsheet provide alternative methodology for 
incorporating these more complex thresholds and associated weighting 
functions.
---------------------------------------------------------------------------

    \1\ For most recent version of the NMFS User Spreadsheet, see: 
http://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm.
---------------------------------------------------------------------------

    The User Spreadsheet accounts for effective hearing ranges using 
Weighting Factor Adjustments (WFAs), and the COU's application uses the 
recommended values for vibratory and impact driving therein. NMFS' new 
acoustic thresholds use dual metrics of SELcum and peak 
sound level (PK) for impulsive sounds (e.g., impact pile driving) and 
SELcum for non-impulsive sounds (e.g., vibratory pile 
driving) (Table 3). The COU used proxy source level measurements taken 
from similar pile driving events (as described in ``Estimated Take by 
Incidental Harassment''), and using the User Spreadsheet, applied the 
updated PTS onset thresholds for impulsive PK and SELcum in 
the new acoustic guidance to determine distance to the isopleths for 
PTS onset for impact pile driving. For vibratory pile driving, the COU 
used the User Spreadsheet to determine isopleth estimates for PTS onset 
using the cumulative sound exposure level metric (LE) 
(http://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm). In determining 
the cumulative sound exposure levels, the Guidance considers the 
duration of the activity, the sound exposure level produced by the 
source during one working day, and the effective hearing range of the 
receiving species. In the case of the duel metric acoustic thresholds 
(Lpk and LE) for impulsive sound, the larger of 
the two isopleths for calculating PTS onset is used. These values were 
then used to develop mitigation measures for proposed pile driving 
activities. The exclusion zone effectively represents the mitigation 
zone that would be established around each pile to prevent Level A 
harassment (PTS onset) to marine mammals (Table 4), while the zones of 
influence (ZOI) provide estimates of the areas within which Level B 
harassment might occur for impact/vibratory pile driving and quarry 
blasting (Table 5).
    As discussed below, some of the proxy source levels, and the 
resulting PTS isopleth and harassment zone calculations, have been 
modified since the FR notice for the proposed IHA was published.

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

Monitoring and Shutdown for Pile Driving

    The following measures would apply to the COU's mitigation through 
the exclusion zone and zone of influence:
    Exclusion Zone--For all pile driving activities, the COU will 
establish an exclusion zone intended to contain the area in which Level 
A harassment thresholds are exceeded. The purpose of the exclusion zone 
is to define an area within which shutdown of construction activity 
would occur upon sighting of a marine mammal within that area (or in 
anticipation of an animal entering the defined area), thus preventing 
potential injury of marine mammals. Calculated distances to the updated 
PTS onset acoustic thresholds are shown in Table 4. Some of these 
distances have changed since the publication of the FR notice for the 
proposed IHA, as NMFS has incorporated more appropriate proxy source 
levels (see Underwater Sound) for some of the pile sizes based on 
Caltrans 2014 and 2015, as well as source levels used for recent Navy 
pile driving construction IHAs (79 FR 43429; 81 FR 66628; Navy, 2014). 
The greatest calculated distance to the Level A harassment threshold 
during impact pile driving, assuming a targeted maximum of 5 piles 
driven per day, is 397.6 m for low-frequency cetaceans (humpback 
whale). For mid-frequency cetaceans (killer whale), phocid pinnipeds 
(harbor seal), and otariid pinnipeds (Steller sea lion), the distances 
are 14.1 m, 212.8 m, and 15.5 m, respectively (Table 4). Calculated 
distances to the PTS onset threshold during vibratory pile driving 
range from a maximum of 14.7 m for low-frequency cetaceans to 0.6 m for 
otariids--depending on the specific type of piles/sheets that are 
installed or removed (Table 4).

[[Page 23540]]



  Table 4--Pile Driving Activities and Calculated Distances to Level A Harassment Isopleths (Onset PTS Threshold Using NMFS' New Acoustic Guidance) and
                                                           Level A Shutdown (Exclusion) Zones
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Estimated duration                   Level A harassment zone/shutdown zone (m) ** (new
                                                 ----------------------------------------------------                      guidance)
                     Source                                       Piles                              ---------------------------------------------------
                                                   Number of    driven per   Hours per     Days of         LF           MF           PW           OW
                                                     piles         day          day         effort     Cetaceans    Cetaceans    Pinnipeds    Pinnipeds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Vibratory Installation Sheet....................        1,700           15          0.5           95       4.1/10       0.4/10       2.5/10       0.2/10
Vibratory Installation 18''.....................          150           10         1.25           15       9.2/10       0.8/10       5.6/10       0.4/10
Vibratory Installation 30''.....................           40            5            1            8      14.7/15       1.3/10       8.9/10       0.6/10
Vibratory Removal Steel 18''....................          195           10         1.25           35       9.2/10       0.8/10       5.6/10       0.4/10
Vibratory Removal Steel 18''....................          150           10         1.25           35       9.2/10       0.8/10       5.6/10       0.4/10
Vibratory Removal Timber........................           55           10         1.25          5.5       2.3/10       0.2/10       1.4/10       0.1/10
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                    Number of        Piles  Strikes per      Days of           LF           MF           PW           OW
                                                        piles   driven per         pile       effort    Cetaceans    Cetaceans    Pinnipeds    Pinnipeds
                                                                       day
--------------------------------------------------------------------------------------------------------------------------------------------------------
Impact Installation 30'' (SEL Calc) *...........           40            5          200            8    397.6/400      14.1/15    212.8/215      15.5/15
                                                                         4  ...........           10    342.6/340      12.2/15    183.3/185      13.3/15
                                                                         3  ...........           14    282.8/280      10.1/10    151.4/150        11/10
                                                                         2  ...........           20    215.8/215       7.7/10    115.5/115       8.4/10
                                                                         1  ...........           40      136/135       4.8/10      72.8/75       5.3/10
                                                                        10  ...........            4    630.1/630      22.4/25    337.2/340      24.6/25
                                                                        20  ...........            2  1000.2/1000      35.6/35    535.3/535        39/40
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Distances to the Level A harassment (PTS onset) isopleth are based on the cumulative sound exposure level (LE) acoustic threshold; the modeled
  distances to the PTS onset isopleth were smaller using the Lpk metric (see Table 8 in the application), and therefore, not used to establish shutdown
  zones.
** Calculated distances to the Level A harassment zones do assume additional sound reductions that may result from implementation of certain types of
  sound attenuation devices (e.g., air bubble curtains).

    The established shutdown zones corresponding to the Level A 
harassment zones for each activity are shown in Table 4 and are as 
follows:
     For all vibratory pile driving activities except vibratory 
installation of 30'' steel pile, a 10-m radius shutdown zone will be 
employed for all species observed. For vibratory installation of 30'' 
steel pile a 15-m radius shutdown zone will be employed.
     During impact pile driving, a shutdown zone will be 
determined by the number of piles to be driven that day as follows: If 
a maximum of five piles are to be driven that day, shutdown during the 
first driven pile will occur if a marine mammal enters the `5-pile' 
radius. After the first pile is driven, if no marine mammals have been 
observed within the `5-pile' radius, the `4-pile' radius will become 
the shutdown radius. This pattern will continue unless an animal is 
observed within the most recent shutdown radius, at which time that 
shutdown radius will remain in effect for the rest of the workday. 
Shutdown radii for each species, depending on number of piles driven, 
are as follows:
    [cir] 5-pile radius: Humpback whale, 400 m; killer whale, 15 m; 
harbor seal, 215 m; Steller sea lion, 15 m.
    [cir] 4-pile radius: Humpback whale, 340 m; killer whale, 15 m; 
harbor seal, 185 m; Steller sea lion, 15 m.
    [cir] 3-pile radius: Humpback whale, 280 m; killer whale, 10 m; 
harbor seal, 150 m; Steller sea lion, 10 m.
    [cir] 2-pile radius: Humpback whale, 215 m; killer whale, 10 m; 
harbor seal, 115 m; Steller sea lion, 10 m.
    [cir] 1-pile radius: Humpback whale, 135 m; killer whale, 10 m; 
harbor seal, 75 m; Steller sea lion, 10 m.
    A shutdown will occur prior to a marine mammal entering a shutdown 
zone appropriate for that species and the concurrent work activity. 
Activity will cease until the observer is confident that the animal is 
clear of the shutdown zone: The animal will be considered clear if:
     It has been observed leaving the shutdown zone; or
     It has not been seen in the shutdown zone for 30 minutes 
for cetaceans and 15 minutes for pinnipeds.
    If shutdown lasts for more than 30 minutes, pre-activity monitoring 
(see below) must recommence.
    If the exclusion zone is obscured by fog or poor lighting 
conditions, pile driving will not be initiated until the exclusion zone 
is clearly visible. Should such conditions arise while impact driving 
is underway, the activity would be halted.
    Level B Harassment Zone (Zone of Influence)--The zone of influence 
(ZOI) refers to the area(s) in which SPLs equal or exceed NMFS' current 
Level B harassment thresholds (160 and 120 dB rms for pulsed and non-
pulsed continuous sound, respectively). ZOIs provide utility for 
monitoring that is conducted for mitigation purposes (i.e., exclusion 
zone monitoring) by establishing monitoring protocols for areas 
adjacent to the exclusion zone. Monitoring of the ZOI enables observers 
to be aware of, and communicate about, the presence of marine mammals 
within the project area but outside the exclusion zone and thus prepare 
for potential shutdowns of activity should those marine mammals 
approach the exclusion zone. However, the primary purpose of ZOI 
monitoring is to allow documentation of incidents of Level B 
harassment; ZOI monitoring is discussed in greater detail later (see 
``Monitoring and Reporting''). The modeled radial distances for ZOIs 
for impact and vibratory pile driving and removal (not taking into 
account landmasses which are expected to limit the actual ZOI radii) 
are shown in Table 6.
    In order to document observed incidents of harassment, monitors 
will record all marine mammals observed within the ZOI. Modeling was

[[Page 23541]]

performed to estimate the ZOI for impact pile driving (the areas in 
which SPLs are expected to equal or exceed 160 dB rms during impact 
driving) and for vibratory pile driving (the areas in which SPLs are 
expected to equal or exceed 120 dB rms during vibratory driving and 
removal). Results of this modeling showed the ZOI for impact driving 
would extend to a radius of 1,000 m from the pile being driven and the 
ZOI for vibratory pile driving would extend to a maximum radius of 
11,659 m from the pile being driven. However, due to the geography of 
the project area, landmasses surround Dutch Harbor and Iliuliuk Bay are 
expected to limit the propagation of sound from construction activities 
such that the actual distances to the ZOI extent for vibratory pile 
driving will be substantially smaller than those described above. 
Modeling results of the ensonified areas, taking into account the 
attenuation provided by landmasses, suggest the actual ZOI will extend 
to a maximum distance of 3,300 m for vibratory driving. Due to this 
adjusted ZOI, and due to the monitoring locations chosen by the COU 
(see the Monitoring Plan in Appendix E of the application for details), 
we expect that monitors will be able to observe the entire modeled ZOI 
for both impact and vibratory pile driving, and thus we expect data 
collected on incidents of Level B harassment to be relatively accurate. 
The modeled areas of the ZOIs for impact and vibratory driving, taking 
into account the attenuation provided by landmasses in attenuating 
sound from the construction project, are shown in Appendix B of the 
application. The actual Level B harassment/monitoring zones for impact 
pile driving (1,000 m) and vibratory pile driving (3,300 m) are shown 
in Table 6. Some of these distances have changes since the publication 
of the FR notice for the proposed IHA, as NMFS has incorporated more 
appropriate proxy source levels (see Underwater Sound) for some of the 
pile sizes based on Caltrans 2014 and 2015, as well as proxy source 
levels used for recent Navy pile driving construction IHAs (79 FR 
43429; 81 FR 66628; Navy, 2014).

Marine Mammal Monitoring

    Qualified observers will be on site before, during, and after all 
pile-driving activities. The Level A and Level B harassment zones for 
underwater noise will be monitored before, during, and after all in-
water construction activity. The observers will be authorized to shut 
down activity if pinnipeds or cetaceans are observed approaching or 
within the shutdown zone of any construction activities.
    Observers will follow observer protocols, meet training 
requirements, fill out data forms and report findings in accordance 
with protocols reviewed and approved by NMFS. A detailed Marine Mammal 
Monitoring Plan is found in Appendix E of the application.
    If marine mammals are observed approaching or within the shutdown 
zone, shutdown procedures will be implemented to prevent unauthorized 
exposure. If marine mammals are observed within the monitoring zone 
(ZOI), the sighting will be documented as a potential Level B take and 
the animal behaviors shall be documented. If the number of marine 
mammals exposed to Level B harassment approaches the number of takes 
allowed by the IHA, the COU will notify NMFS and seek further 
consultation. If any marine mammal species are encountered that are not 
authorized by the IHA and are likely to be exposed to sound pressure 
levels greater than or equal to the Level B harassment thresholds, then 
the COU will shut down in-water activity to avoid take of those 
species.

Pre-Activity Monitoring

    Prior to the start of daily in-water construction activity, or 
whenever a break in pile driving of 30 minutes or longer occurs, the 
observer will observe the shutdown and monitoring zones for a period of 
30 minutes. The shutdown zone will be cleared when a marine mammal has 
not been observed within zone for that 30-minute period. If a marine 
mammal is observed within the shutdown zone, a soft-start (described 
below) cannot proceed until the marine mammal has left the zone or has 
not been observed for 15 minutes (for pinnipeds) and 30 minutes (for 
cetaceans). If the Level B harassment zone has been observed for 30 
minutes and non-permitted species are not present within the zone, soft 
start procedures can commence and work can continue even if visibility 
becomes impaired within the Level B zone. If the Level B zone is not 
visible while work continues, exposures will be recorded at the 
estimated exposure rate for each permitted species. If work ceases for 
more than 30 minutes, the pre-activity monitoring of both zones must 
recommence

Soft Start

    The use of a ``soft-start'' procedure is believed to provide 
additional protection to marine mammals by providing a warning and an 
opportunity to leave the area prior to the hammer operating at full 
capacity. Soft start procedures will be used prior to pile removal, 
pile installation, and in-water fill placement to allow marine mammals 
to leave the area prior to exposure to maximum noise levels. For 
vibratory hammers, the soft start technique will initiate noise from 
the hammer for short periods at a reduced energy level, followed by a 
brief waiting period and repeating the procedure two additional times. 
For impact hammers, the soft start technique will initiate several 
strikes at a reduced energy level, followed by a brief waiting period. 
This procedure would also be repeated two additional times. Equipment 
used for fill placement will be idled near the waterside edge of the 
fill area for 15 minutes prior to performing in-water fill placement.

In-Water or Over-Water Construction Activities

    During in-water or over-water construction activities having the 
potential to affect marine mammals, but not involving a pile driver, a 
shutdown zone of 10 m will be monitored to ensure that marine mammals 
are not endangered by physical interaction with construction equipment. 
These activities could include, but are not limited to, the positioning 
of the pile on the substrate via a crane (``stabbing'' the pile) or the 
removal of the pile from the water column/substrate via a crane 
(``deadpull''), or the slinging of construction materials via crane.

Sound Attenuation Devices

    Sound attenuation devices (e.g., air bubble curtains, pile caps, or 
other attenuating device) shall be used during all impact pile driving 
operations. Sound levels can be greatly reduced during impact pile 
driving using sound attenuation devices. The exact reduction of noise 
level by a noise attenuator varies, and depends on many factors such as 
water depth, current flow, and in the case of an air bubble curtain, 
bubble density and bubble diameter, etc. Caltrans (2015) and Navy 
(2014) provide information on the general effectiveness of various air 
bubble curtain systems in attenuating underwater sound. In low current 
situations, 5 to 15 dB of noise reduction has been achieved (Caltrans, 
2015). Data are more limited on the effectiveness of pile caps in 
reducing the sound generated by the pile during impact pile driving.

Vessel Interactions

    To minimize impacts from vessels interactions with marine mammals, 
the crews aboard project vessels will follow NMFS's marine mammal 
viewing guidelines and regulations as practicable. (https://

[[Page 23542]]

alaskafisheries.noaa.gov/protectedresources/mmv/guide.htm).

Mitigation Conclusions

    We have carefully evaluated the COU's proposed mitigation measures 
and considered their likely effectiveness relative to implementation of 
similar mitigation measures in previously issued IHAs to determine 
whether they are likely to affect the least practicable impact on the 
affected marine mammal species and stocks and their habitat. Our 
evaluation of potential measures included consideration of the 
following factors in relation to one another:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure is expected to minimize adverse impacts 
to marine mammals;
    (2) The proven or likely efficacy of the specific measure to 
minimize adverse impacts as planned; and
    (3) The practicability of the measure for applicant implementation.
    Based on our evaluation of the COU's proposed measures, we have 
determined that the mitigation measures provide the means of affecting 
the least practicable impact on marine mammal species or stocks and 
their habitat.

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 
incidental take authorizations must include the suggested means of 
accomplishing the necessary monitoring and reporting that will result 
in increased knowledge of the species and of the level of taking or 
impacts on populations of marine mammals that are expected to be 
present in the proposed action area.

Monitoring

    Any monitoring requirement we prescribe should accomplish one or 
more of the following general goals:
    1. An increase in the probability of detecting marine mammals, both 
within defined zones of effect (thus allowing for more effective 
implementation of the mitigation) and in general to generate more data 
to contribute to the analyses mentioned below;
    2. An increase in our understanding of how many marine mammals are 
likely to be exposed to stimuli that we associate with specific adverse 
effects, such as behavioral harassment or hearing threshold shifts;
    3. An increase in our understanding of how marine mammals respond 
to stimuli expected to result in incidental take and how anticipated 
adverse effects on individuals may impact the population, stock, or 
species (specifically through effects on annual rates of recruitment or 
survival) through any of the following methods:
     Behavioral observations in the presence of stimuli 
compared to observations in the absence of stimuli (need to be able to 
accurately predict pertinent information, e.g., received level, 
distance from source);
     Physiological measurements in the presence of stimuli 
compared to observations in the absence of stimuli (need to be able to 
accurately predict pertinent information, e.g., received level, 
distance from source); and
     Distribution and/or abundance comparisons in times or 
areas with concentrated stimuli versus times or areas without stimuli.
    4. An increased knowledge of the affected species; or
    5. An increase in our understanding of the effectiveness of certain 
mitigation and monitoring measures.
    The COU submitted a Marine Mammal Monitoring Plan as part of their 
IHA application (Appendix E of the application; also available online 
at: http://www.nmfs.noaa.gov/pr/permits/incidental/). The COU's 
proposed Marine Mammal Monitoring Plan was created with input from NMFS 
and was based on similar plans that have been successfully implemented 
by other action proponents under previous IHAs for pile driving 
projects.

Visual Marine Mammal Observations

    The COU will collect sighting data and will record behavioral 
responses to construction activities for marine mammal species observed 
in the project location during the period of activity. All marine 
mammal observers (MMOs) will be trained in marine mammal identification 
and behaviors and are required to have no other construction-related 
tasks while conducting monitoring. The COU will monitor the exclusion 
zone (shutdown zone) and Level B harassment zone before, during, and 
after pile driving, with observers located at the best practicable 
vantage points (See Figure 3 in the Marine Mammal Monitoring Plan for 
the observer locations planned for use during construction). Based on 
our requirements, the Marine Mammal Monitoring Plan would implement the 
following procedures for pile driving:
     During observation periods, observers will continuously 
scan the area for marine mammals using binoculars and the naked eye. 
Observers will work shifts of a maximum of four consecutive hours 
followed by an observer rotation or a 1-hour break and will work no 
more than 12 hours in any 24-hour period.
     Observers will collect data including, but not limited to, 
environmental conditions (e.g., sea state, precipitation, glare, etc.), 
marine mammal sightings (e.g., species, numbers, location, behavior, 
responses to construction activity, etc.), construction activity at the 
time of sighting, and number of marine mammal exposures. Observers will 
conduct observations, meet training requirements, fill out data forms, 
and report findings in accordance with this IHA.
     During all observation periods, observers will use 
binoculars and the naked eye to search continuously for marine mammals.
     If the exclusion zone is obscured by fog or poor lighting 
conditions, pile driving will not be initiated until the exclusion zone 
is clearly visible. Should such conditions arise while impact driving 
is underway, the activity would be halted.
     Observers will implement mitigation measures including 
monitoring of the shutdown and monitoring zones, clearing of the zones, 
and shutdown procedures.
     Observers will be in continuous contact with the 
construction personnel via two-way radio. A cellular phone will be used 
as back-up communications and for safety purposes.
     Individuals implementing the monitoring protocol will 
assess its effectiveness using an adaptive approach. MMOs will use 
their best professional judgment throughout implementation and seek 
improvements to these methods when deemed appropriate. Any 
modifications to protocol will be coordinated between NMFS and the COU.

Data Collection

    We require that observers use approved data forms. Among other 
pieces of information, the COU will record detailed information about 
any implementation of shutdowns, including the distance of animals to 
the pile being driven, a description of specific actions that ensued, 
and resulting behavior of the animal, if any. In addition, the COU will 
attempt to distinguish between the number of individual animals taken 
and the number of incidents of take, when possible. We require that, at 
a minimum, the following information be collected on sighting forms:

[[Page 23543]]

     Date and time that permitted construction activity begins 
or ends;
     Weather parameters (e.g. percent cloud cover, percent 
glare, visibility) and Beaufort sea state;
     Species, numbers, and, if possible, sex and age class of 
observed marine mammals;
     Construction activities occurring during each sighting;
     Marine mammal behavior patterns observed, including 
bearing and direction of travel;
     Specific focus should be paid to behavioral reactions just 
prior to, or during, soft-start and shutdown procedures;
     Location of marine mammal, distance from observer to the 
marine mammal, and distance from pile driving activities to marine 
mammals;
     Record of whether an observation required the 
implementation of mitigation measures, including shutdown procedures 
and the duration of each shutdown; and
     Other human activity in the area. Record the hull numbers 
of fishing vessels if possible.

Sound Source and Attenuation Verification

    The companion User Spreadsheet provided with NMFS' new acoustic 
guidance uses multiple conservative assumption which may result in 
unrealistically large isopleths associated with PTS onset. The COU may 
elect to verify the values used for source levels and sound attenuation 
in the various exclusion radii calculations. This would be achieved 
using the techniques and equipment for sound source verification 
discussed in Appendix A of the application. Sound levels would be 
measured at the earliest possibility during pile driving at 10, 100, 
300, and 500 meters from the sound source. For the purpose of 
recalculating the observation and hazard radii, measured source levels 
(at 10 m) would be substituted for the assumed source levels for piles 
of the same size and method of installation as the measured pile. The 
distant values would be plotted and a logarithmic line of best fit used 
to determine the site specific attenuation rate (geometric loss 
coefficient) experienced at the project site. If the measured geometric 
loss coefficient is higher than the typically-used value of 15, the 
observation and hazard radii for all pile driving activities will be 
revised by applying the site specific measured values to the practical 
spreading loss equation. The site specific radii would be used for the 
remaining duration of construction. The COU may elect not to exercise 
this option, if the cost of shutdown during impact pile driving is not 
anticipated to warrant additional measurements.
    The COU must obtain approval from NMFS of any new exclusion zone 
before it may be implemented.

Reporting

Annual Report
    A draft report will be submitted within 90 calendar days of the 
completion of the activity. The report will include information on 
marine mammal observations pre-activity, during-activity, and post-
activity during pile driving days, and will provide descriptions of any 
behavioral responses to construction activities by marine mammals and a 
complete description of any mitigation shutdowns and results of those 
actions, as well as an estimate of total take based on the number of 
marine mammals observed during the course of construction. A final 
report must be submitted within 30 days following resolution of 
comments from NMFS on the draft report. The report shall include at a 
minimum:
     General data:
    [cir] Date and time of activity.
    [cir] Water conditions (e.g., sea-state).
    [cir] Weather conditions (e.g., percent cover, percent glare, 
visibility).
     Specific pile driving data:
    [cir] Description of the pile driving activity being conducted 
(pile locations, pile size and type), and times (onset and completion) 
when pile driving occurs.
    [cir] The construction contractor and/or marine mammal monitoring 
staff will coordinate to ensure that pile driving times and strike 
counts are accurately recorded. The duration of soft start procedures 
should be noted as separate from the full power driving duration.
    [cir] Detailed description of the sound attenuation system 
utilized, including the design.
    [cir] Description of in-water construction activity not involving 
pile driving (location, type of activity, onset and completion times).
     Pre-activity observational survey-specific data:
    [cir] Date and time survey is initiated and terminated.
    [cir] Description of any observable marine mammals and their 
behavior in the immediate area during monitoring.
    [cir] Times when pile driving or other in-water construction is 
delayed due to presence of marine mammals within shutdown zones.
     During-activity observational survey-specific data:
    [cir] Description of any observable marine mammal behavior within 
monitoring zones or in the immediate area surrounding the monitoring 
zones, including the following:
    [ssquf] Distance from animal to pile driving sound source.
    [ssquf] Reason why/why not shutdown implemented.
    [ssquf] If a shutdown was implemented, behavioral reactions noted 
and if they occurred before or after implementation of the shutdown.
    [ssquf] If a shutdown was implemented, the distance from animal to 
sound source at the time of the shutdown.
    [ssquf] Behavioral reactions noted during soft starts and if they 
occurred before or after implementation of the soft start.
    [ssquf] Distance to the animal from the sound source during soft 
start.
     Post-activity observational survey-specific data:
    [cir] Results, which include the detections and behavioral 
reactions of marine mammals, the species and numbers observed, sighting 
rates and distances,
    [cir] Refined exposure estimate based on the number of marine 
mammals observed. This may be reported as a rate of take (number of 
marine mammals per hour or per day), or using some other appropriate 
metric.
General Notifications
    In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner not authorized by the 
IHA, such as a Level A harassment, or a take of a marine mammal species 
other than those authorized, the COU would immediately cease the 
specified activities and immediately report the incident to the Chief 
of the Permits and Conservation Division, Office of Protected 
Resources, NMFS, and the Alaska Stranding Coordinator.
    The report would include the following information:
     Time, date, and location (latitude/longitude) of the 
incident;
     Description of the incident;
     Status of all sound source use in the 24 hours preceding 
the incident;
     Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);
     Description of all marine mammal observations in the 24 
hours preceding the incident;
     Species identification or description of the animal(s) 
involved;
     Fate of the animal(s); and
     Photographs or video footage of the animal(s) (if 
equipment is available).
    Activities would not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS would work with the COU to 
determine what is necessary to

[[Page 23544]]

minimize the likelihood of further prohibited take and ensure MMPA 
compliance. The COU would not be able to resume their activities until 
notified by NMFS via letter, email, or telephone.
    In the event that the COU discovers an injured or dead marine 
mammal, and determines that the cause of the injury or death is unknown 
and the death is relatively recent (i.e., in less than a moderate state 
of decomposition), the COU would immediately report the incident to 
Jolie Harrison ([email protected]), Chief of the Permits and 
Conservation Division, Office of Protected Resources, NMFS, and Mandy 
Migura ([email protected]), Alaska Stranding Coordinator. The 
report would include the same information identified in the paragraph 
above. Construction related activities would be able to continue while 
NMFS reviews the circumstances of the incident. NMFS would work with 
the COU to determine whether modifications in the activities are 
appropriate.
    In the event that the COU discovers an injured or dead marine 
mammal, and determines that the injury or death is not associated with 
or related to the activities authorized in the IHA (e.g., previously 
wounded animal, carcass with moderate to advanced decomposition, or 
scavenger damage), the COU would report the incident to Jolie Harrison 
([email protected]), Chief of the Permits and Conservation 
Division, Office of Protected Resources, NMFS, and Mandy Migura 
([email protected]), Alaska Stranding Coordinator, within 24 hours 
of the discovery. The COU would provide photographs or video footage 
(if available) or other documentation of the stranded animal sighting 
to NMFS and the Marine Mammal Stranding Network. The COU can continue 
its operations under such a case.

Estimated Take by Incidental Harassment

    Except with respect to certain activities not pertinent here, 
section 3(18) of the MMPA defines ``harassment'' as: ``. . . any act of 
pursuit, torment, or annoyance which (i) has the potential to injure a 
marine mammal or marine mammal stock in the wild (Level A harassment); 
or (ii) has the potential to disturb a marine mammal or marine mammal 
stock in the wild by causing disruption of behavioral patterns, 
including, but not limited to, migration, breathing, nursing, breeding, 
feeding, or sheltering (Level B harassment).''
    All anticipated takes would be by Level B harassment, resulting 
from vibratory and impact pile driving and involving temporary changes 
in behavior. Based on the best available information, the proposed 
activities--vibratory and impact pile driving--would not result in 
serious injuries or mortalities to marine mammals even in the absence 
of the planned mitigation and monitoring measures. Additionally, the 
mitigation and monitoring measures are expected to minimize the 
potential for injury, such that take by Level A harassment is 
considered discountable.
    If a marine mammal responds to a stimulus by changing its behavior 
(e.g., through relatively minor changes in locomotion direction/speed 
or vocalization behavior), the response may or may not constitute 
taking at the individual level, and is unlikely to affect the stock or 
the species as a whole. However, if a sound source displaces marine 
mammals from an important feeding or breeding area for a prolonged 
period, impacts on animals or on the stock or species could potentially 
be significant (e.g., Lusseau and Bejder, 2007; Weilgart, 2007). Given 
the many uncertainties in predicting the quantity and types of impacts 
of sound on marine mammals, it is common practice to estimate how many 
animals are likely to be present within a particular distance of a 
given activity, or exposed to a particular level of sound.
    This practice potentially overestimates the numbers of marine 
mammals taken, as it is often difficult to distinguish between the 
individual animals harassed and incidences of harassment. In 
particular, for stationary activities, it is more likely that some 
smaller number of individuals may accrue a number of incidences of 
harassment per individual than for each incidence to accrue to a new 
individual, especially if those individuals display some degree of 
residency or site fidelity and the impetus to use the site (e.g., 
because of foraging opportunities) is stronger than the deterrence 
presented by the harassing activity.
    The COU has requested authorization for the incidental taking of 
small numbers of Steller sea lions, harbor seals, humpback whales, and 
killer whales that may result from pile driving activities associated 
with the UMC dock construction project described previously in this 
document. In order to estimate the potential incidents of take that may 
occur incidental to the specified activity, we must first estimate the 
extent of the sound field that may be produced by the activity and then 
incorporate information about marine mammal density or abundance in the 
project area. We first provide information on applicable sound 
thresholds for determining effects to marine mammals before describing 
the information used in estimating the sound fields, the available 
marine mammal density or abundance information, and the method of 
estimating potential incidences of take.

Sound Thresholds

    We use sound exposure thresholds to determine when an activity that 
produces sound might result in impacts to a marine mammal such that a 
``take'' by harassment might occur. As discussed above, NMFS has 
recently revised PTS (and temporary threshold shift) onset acoustic 
thresholds for impulsive and non-impulsive sound as part of its new 
acoustic guidance (refer to Table 3 for those thresholds). The Guidance 
does not address Level B harassment, nor airborne noise harassment; 
therefore, COU uses the current NMFS acoustic exposure criteria to 
determine exposure to airborne and underwater noise sound pressure 
levels for Level B harassment (Table 5).

 Table 5--Current NMFS Acoustic Exposure Criteria for Level B Harassment
------------------------------------------------------------------------
           Criterion                Definition           Threshold
------------------------------------------------------------------------
Level B harassment              Behavioral         160 dB re: 1
 (underwater).                   disruption.        [micro]Pa (impulsive
                                                    source *)/120 dB re:
                                                    1 [micro]Pa
                                                    (continuous source
                                                    *) (rms).
Level B harassment (airborne)   Behavioral         90 dB re: 20
 **.                             disruption.        [micro]Pa (harbor
                                                    seals)/100 dB re: 20
                                                    [micro]Pa (other
                                                    pinnipeds)
                                                    (unweighted).
------------------------------------------------------------------------
* Impact pile driving produces impulsive noise; vibratory pile driving
  produces non-pulsed (continuous) noise.
** NMFS has not established any formal criteria for harassment resulting
  from exposure to airborne sound. However, these thresholds represent
  the best available information regarding the effects of pinniped
  exposure to such sound and NMFS' practice is to associate exposure at
  these levels with Level B harassment.


[[Page 23545]]

Distance to Sound Thresholds

    Underwater Sound Propagation Formula--Pile driving generates 
underwater noise that can potentially result in disturbance to marine 
mammals in the project area. Transmission loss (TL) is the decrease in 
acoustic intensity as an acoustic pressure wave propagates out from a 
source. TL parameters vary with frequency, temperature, sea conditions, 
current, source and receiver depth, water depth, water chemistry, and 
bottom composition and topography. The general formula for underwater 
TL is:
TL = B * log10(R1/R2),

where
R1 = the distance of the modeled SPL from the driven 
pile, and
R2 = the distance from the driven pile of the initial 
measurement

    This formula neglects loss due to scattering and absorption, which 
is assumed to be zero here. The degree to which underwater sound 
propagates away from a sound source is dependent on a variety of 
factors, most notably the water bathymetry and presence or absence of 
reflective or absorptive conditions including in-water structures and 
sediments. Spherical spreading occurs in a perfectly unobstructed 
(free-field) environment not limited by depth or water surface, 
resulting in a 6 dB reduction in sound level for each doubling of 
distance from the source (20*log(range)). Cylindrical spreading occurs 
in an environment in which sound propagation is bounded by the water 
surface and sea bottom, resulting in a reduction of 3 dB in sound level 
for each doubling of distance from the source (10*log(range)). A 
practical spreading value of fifteen is often used under conditions, 
such as Dutch Harbor, where water depth increases as the receiver moves 
away from the shoreline, resulting in an expected propagation 
environment that would lie between spherical and cylindrical spreading 
loss conditions. Practical spreading loss (4.5 dB reduction in sound 
level for each doubling of distance) is assumed here.
    Underwater Sound--During the installation of piles, the project has 
the potential to increase underwater noise levels. This could result in 
disturbance to pinnipeds and cetaceans that occur within the Level B 
harassment zone. The intensity of pile driving sounds is greatly 
influenced by factors such as the type of piles, hammers, and the 
physical environment in which the activity occurs. A large quantity of 
literature regarding SPLs recorded from pile driving projects is 
available for consideration. In order to determine reasonable SPLs and 
their associated effects on marine mammals that are likely to result 
from pile driving at the UMC dock, studies with similar properties to 
the specified activity were evaluated.
    According to studies by the California Department of Transportation 
(Caltrans), the installation of steel sheet piles using a vibratory 
hammer can result in underwater noise levels reaching a source level of 
163 dB RMS or 162 dBSEL at 10 m (Caltrans, 2015). PND 
Engineers, Inc. performed acoustic measurements during vibratory 
installation of steel sheet pile at a similar construction project in 
Unalaska, Alaska, and found average SPLs of 160.7 dB RMS (Unisea, 
2015). This lower value was used to calculate the harassment radii for 
vibratory installation sheet pile and is discussed further in Appendix 
A of the application.
    Underwater noise levels during the vibratory removal and 
installation of 18-inch steel pile can reach a source level of 162 dB 
RMS at 10 m (Illingworth and Rodkin, 2012; Navy, 2014). Because there 
was little information on the underwater noise levels of the removal of 
timber piles, the levels used for analysis (153 dB RMS at 10 m) were 
taken from the installation of timber piles (Illingworth and Rodkin, 
2012; Navy, 2014). Underwater noise levels during the impact pile 
driving of a 30-inch steel pile can reach a source level of 190 dB RMS 
(177 dBSEL) at 10 m (Caltrans, 2014 and 2015), whereas the 
underwater noise from the vibratory driving of 30-inch steel pile can 
result in a source level of 166 dB RMS at 10 m (Illingworth and Rodkin, 
2012; Navy, 2014).
    Dutch Harbor does not represent open water, or free field, 
conditions. Therefore, sounds would attenuate as they encounter land 
masses. As a result, and as described above, pile driving noise in the 
project area is not expected to propagate to the calculated distances 
for the 120 dB thresholds as shown in Table 6. See Appendix B of the 
application for figures depicting the actual extents of areas in which 
each underwater sound threshold is predicted to occur at the project 
area due to pile driving, taking into account the attenuation provided 
by landmasses.

  Table 6--Modeled Distances to the NMFS Level B Harassment Thresholds
  (isopleths) and Actual Monitoring Zones During Pile Installation and
                                 Removal
------------------------------------------------------------------------
                                                        Monitoring zone
            Threshold               Distance  (m) *           (m)
------------------------------------------------------------------------
Impact driving, disturbance (160  1,000 **..........  1,000.
 dB).
Vibratory removal, disturbance    11,659 *** (steel)  3,300 (steel).
 (120 dB).
                                  1,585 (timber)....  1,600 (timber).
------------------------------------------------------------------------
*Distances shown are modeled maximum distances and do not account for
  landmasses which are expected to reduce the actual distances to sound
  thresholds.
**Calculated distance to the impact pile driving Level B harassment zone
  does not assume additional sound reductions that may result from
  implementation of certain types of sound attenuation devices (e.g.,
  air bubble curtains).
***This is the maximum distance modeled. See Section 5 of the
  application for the modeled distances for each pile driving activity
  type.

    Airborne Sound--During the installation of piles and blasting 
activities at the quarry, the project has the potential to increase 
airborne noise levels. This could result in disturbance to pinnipeds at 
the surface of the water or hauled out along the shoreline of Iliuliuk 
Bay or the Dutch Harbor spit; however, we do not expect animals to haul 
out frequently within Dutch Harbor or the spit due to the amount of 
activity within the area. A spherical spreading loss model (i.e., 6 dB 
reduction in sound level for each doubling of distance from the 
source), in which there is a perfectly unobstructed (free-field) 
environment not limited by depth or water surface, is appropriate for 
use with airborne sound and was used to estimate the distance to the 
airborne thresholds.
    The formula for calculating spherical spreading loss in airborne 
noise is:

TL=GL x log(R1/R2)

where:

TL = Transmission loss (dB)
GL = Geometric Loss Coefficient (20 for spherical spreading in 
airborne noise)

[[Page 23546]]

R1 = Range of the sound pressure level (m)
R2 = Distance from the source of the initial measurement 
(m)

    Noise levels used to calculate airborne harassment radii come from 
Laughlin (2010) and Laughlin (2013) and are summarized in Table 9 of 
the application. Data for vibratory driving from Laughlin (2010) is 
presented in dBL5EQ, or the 5-minute average continuous 
sound level. In this case dBRMS values would be calculated 
in a similar fashion, so these dBL5EQ were considered 
equivalent to the standard dBRMS. Impact pile driving noise 
levels were taken from a recent Washington State Department of 
Transportation IHA application which used data collected by Laughlin 
(2013). A report was not available for this data, but it is assumed to 
be provided in dBRMS. Only A-weighted airborne noise levels 
were available for quarry plasting (Giroux, 2009), so a conservative 
maximum level was selected, dBALMAX.
    Based on the spherical spreading loss equation, the calculated 
airborne Level B harassment zones would extend out to the following 
distances:
     For the vibratory installation of 18-inch steel piles, the 
calculated airborne Level B harassment zone for harbor seals is 11.4 m; 
for Steller sea lions, the distance is 3.6 m;
     For the vibratory installation of 30-inch steel piles, the 
calculated airborne Level B harassment zone for harbor seals is 31.9 
meters; for Steller sea lions, the distance is 10.1 m;
     For the impact installation of 24-inch steel piles, the 
calculated airborne Level B harassment zone for harbor seals is 152.4 
m; for Steller sea lions, the distance is 48.2 m; and
     For quarry blasting, the calculated Level B harassment 
zone for harbor seals extends to 38.5 m and 12.2 m for Steller sea 
lions.
    Vibratory installation of sheet piles is assumed to create lower 
noise levels than installation of 30-inch round piles, so these values 
will be used for sheet pile driving. Similarly, vibratory removal of 
steel or wooden piles will observe the same harassment radii. For the 
purposes of this analysis, impact installation of 30-inch steel piles 
is assumed to generate similar sound levels to the installation of 24-
inch piles, as no unweighted data was available for the 30-inch piles.
    Since the in-water area encompassed within the above areas is 
located entirely within the underwater Level B harassment zone, the 
pinnipeds that come within these areas will already be recorded as a 
take based on Level B harassment threshold for underwater noise, which 
are in all cases larger than those associated with airborne sound. 
Further, it is not anticipated that any pinnipeds will haul out within 
the airborne harassment zone. Airborne noise thresholds have not been 
established for cetaceans (NOAA, 2015b), and no adverse impacts are 
anticipated.
    Distance from the quarry bottom to the shoreline is an average of 
70-80 m, so exposure to even Level B harassment from blasting noise is 
highly unlikely.
    Therefore, we do not believe that authorization of incidental take 
resulting from airborne sound for pinnipeds is warranted, and airborne 
sound is not discussed further here.

Marine Mammal Occurrence

    The most appropriate information available was used to estimate the 
number of potential incidences of take. Density estimates for Steller 
sea lions, harbor seals, humpback whales, and killer whales in Dutch 
Harbor, and more broadly in the waters surrounding Unalaska Island, are 
not readily available. Likewise, we were not able to find any published 
literature or reports describing densities or estimating abundance of 
either species in the project area. As such, data collected from marine 
mammal surveys represent the best available information on the 
occurrence of both species in the project area.
    Beginning in April 2015, UMC personnel began conducting surveys 
within Dutch Harbor under the direction of an ecological consultant. 
The consultant visited the site every month to ensure that data was 
gathered consistently and comprehensively. Observers monitored for a 
variety of marine mammals, including Steller sea lions, whales, and 
harbor seals. Several observation locations from various vantage points 
were selected for the surveys. Observations took place for 
approximately 15 minutes from each point, and included only marine 
mammals which were inside Dutch Harbor. The survey recorded the type of 
species observed, the number of species observed, the primary activity 
of the species, and any applicable notes. Surveys were conducted 
through July 2016.
    These surveys represent the most recent data on marine mammal 
occurrence in the harbor, and represent the only targeted marine mammal 
surveys of the project area that we are aware of.
    Data from bird surveys of Dutch Harbor conducted by the U.S. Army 
Corps of Engineers (USACE) from 2003-2013, which included observations 
of Steller sea lions in the harbor, were also available; however, we 
determined that these data were unreliable as a basis for prediction of 
marine mammal abundance in the project location as the goal of the 
USACE surveys was to develop a snapshot of waterfowl and seabird 
location and abundance in the harbor, thus the surveys would have been 
designed and carried out differently if the goal had been to document 
marine mammal use of the harbor. Additionally, USACE surveys occurred 
only in winter; as Steller sea lion abundance is expected to vary 
significantly between the breeding and the non-breeding season in the 
project location, data that were collected only during the non-breeding 
season have limited utility in predicting year-round abundance. As 
such, we determined that the data from the surveys commissioned by COU 
in 2015-2016 represents the best available information on marine 
mammals in the project location.

Description of Take Calculation

    The take calculations presented here rely on the best data 
currently available for marine mammal populations in the project 
location. Density data for marine mammal species in the project 
location is not available. Therefore the data collected from marine 
mammal surveys of Dutch Harbor in 2015-2016 represent the best 
available information on marine mammal populations in the project 
location, and this data was used to estimate take. As such, the zones 
that have been calculated to contain the areas ensonified to the Level 
A and Level B thresholds for marine mammals have been calculated for 
mitigation and monitoring purposes and were not used in the calculation 
of take. See Table 7 for total estimated incidents of take. Estimates 
were based on the following assumptions:

     All marine mammals estimated to be in areas ensonified 
by noise exceeding the Level B harassment threshold for impact and 
vibratory driving (as shown in Appendix B of the application) are 
assumed to be in the water 100 percent of the time. This assumption 
is based on the fact that there are no haulouts or rookeries within 
the area predicted to be ensonified to the Level B harassment 
threshold based on modeling.
     Predicted exposures were based on total estimated total 
duration of pile driving/removal hours, which are estimated at 1,470 
hours over the entire project. This estimate is based on a 245 day 
project time frame, an average work day of 12 hours, and a 
conservative estimate that up to approximately 50 percent of time 
(likely less on some days, based on the short pile driving durations 
provided in Table 4) during those work days will include pile 
driving and removal activities (with the rest of the work day spent 
on non-pile driving activities

[[Page 23547]]

which will not result in marine mammal take, such as installing 
templating and bracing, moving equipment, etc.).
     Vibratory or impact driving could occur at any time 
during the ``duration'' and our approach to take calculation assumes 
a rate of occurrence that is the same for any of the calculated 
zones.
     The hourly marine mammal observation rate recorded 
during marine mammal surveys of Dutch Harbor in 2015 is reflective 
of the hourly rate that will be observed during the construction 
project.
     Takes were calculated based on estimated rates of 
occurrence for each species in the project area and this rate was 
assumed to be the same regardless of the size of the zone (for 
impact or vibratory driving/removal).
     Activities that may be accomplished by either impact 
driving or down-the-hole drilling (i.e., fender support/pin piles, 
miscellaneous support piles, and temporary support piles) were 
assumed to be accomplished via impact driving. If any of these 
activities are ultimately accomplished via down-the-hole drilling 
instead of impact driving, this would not result in a change in the 
amount of overall effort (as they will be accomplished via down-the-
hole drilling instead of, and not in addition to, impact driving). 
As take estimates are calculated based on effort and not marine 
mammal densities, this would not change the take estimate.

    Take estimates for Steller sea lions, harbor seals, humpback 
whales, and killer whales were calculated using the following series of 
steps:

    1. The average hourly rate of animals observed during 2015-2016 
marine mammal surveys of Dutch Harbor was calculated separately for 
both species (``Observation Rate''). Thus ``Observation Rate'' (OR) 
= Number of individuals observed/hours of observation;
    2. The 95 percent confidence interval was calculated for the 
data set, and the upper bound of the 95 percent confidence interval 
was added to the Observation Rate to account for variability of the 
small data set (``Exposure Rate''). Thus ``Exposure Rate'' (XR) = 
[micro]OR + CI95 (where [micro]OR = 
average of hourly observation rates and CI95 = 95 percent 
confidence interval (normal distribution);
    3. The total estimated hours of pile driving work over the 
entire project was calculated, as described above (``Duration''); 
Thus ``Duration'' = total number of work days (245) * average pile 
driving/removal hours per day (6) = total work hours for the project 
(1,470); and
    4. The estimated number of exposures was calculated by 
multiplying the ``Duration'' by the estimated ``Exposure Rate'' for 
each species. Thus, estimated takes = Duration * XR.

    Please refer to Appendix G of the application for a more thorough 
description of the statistical analysis of the observation data from 
marine mammal surveys.
    Steller Sea Lion--Steller sea lion density data for the project 
area is not available. Steller sea lions occur year-round in the 
Aleutian Islands and within Unalaska Bay and Dutch Harbor. As described 
above, local abundance in the non-breeding season (winter months) is 
generally lower overall; data from surveys conducted by the COU in 
2015-2016 revealed Steller sea lions were present in Dutch Harbor in 
most months that surveys occurred. We assume, based on marine mammal 
surveys of Dutch Harbor, and based on the best available information on 
seasonal abundance patterns of the species including over 20 years of 
NOAA National Marine Mammal Laboratory (NMML) survey data collected in 
Unalaska, that Steller sea lions will be regularly observed in the 
project area during most or all months of construction. As described 
above, all Steller sea lions in the project area at a given time are 
assumed to be in the water, thus any sea lion within the modeled area 
of ensonification exceeding the Level B harassment threshold would be 
recorded as taken by Level B harassment.
    Estimated take of Steller sea lions was calculated using the 
equations described above, as follows:

mOR = 0.40 animals/hour
CI95 = 0.23 animals/hour
XR = 0.63 animals/hour
Estimated exposures (Level B harassment) = 0.63 * 1,470 = 926

    Thus we estimate that a total of 926 Steller sea lion takes will 
occur as a result of the proposed UMC dock construction project (Table 
7).
    Harbor Seal--Harbor seal density data for the project location is 
not available. We assume, based on the best on the best available 
information, that harbor seals will be encountered in low numbers 
throughout the duration of the project. We relied on the best available 
information to estimate take of harbor seals, which in this case was 
survey data collected from the 2015-2016 marine mammal surveys of Dutch 
Harbor as described above. That survey data showed harbor seals are 
present in the harbor only occasionally (average monthly observation 
rate = 0.41). NMML surveys have not been performed in Dutch Harbor, but 
the most recent NMML surveys of Unalaska Bay confirm that harbor seals 
are present in the area in relatively small numbers, with the most 
recent haulout counts in Unalaska Bay (2008-2011) recording no more 
than 19 individuals at the three known haulouts there. NMML surveys 
have been limited to the months of July and August, so it is not known 
whether harbor seal abundance in the project area varies seasonally. As 
described above, all harbor seals in the project area at a given time 
are assumed to be in the water, thus any harbor seals within the 
modeled area of ensonification exceeding the Level B harassment 
threshold would be recorded as taken by Level B harassment.
    Estimated take of harbor seals was calculated using the equations 
described above, as follows:

mOR = 0.16 animals/hour
CI95 = 0.16 animals/hour
XR = 0.32 animals/hour
Estimated exposures (Level B harassment) = 0.32 * 1,470 hours = 470

    Thus we estimate that a total of 470 harbor seal takes will occur 
as a result of the proposed UMC dock construction project (Table 7).
    Humpback Whale--Humpback whale density data for the project 
location is not available. We assume, based on the best on the best 
available information, that humpback whales will be encountered in low 
numbers throughout the duration of the project. We relied on the best 
available information to estimate take of humpback whales, which in 
this case was survey data collected from the 2015-2016 marine mammal 
surveys of Dutch Harbor as described above. That survey data showed 
humpback whales are present in the harbor only occasionally (average 
monthly observation rate = 0.06). Estimated take of humpback whales was 
calculated using the equations described above, as follows:

mOR = 0.06 animals/hour
CI95 = 0.06 animals/hour
XR = 0.12 animals/hour
Estimated exposures (Level B harassment) = 0.12 * 1,470 hours = 176

    Thus we estimate that a total of 176 humpback whale takes will 
occur as a result of the proposed UMC dock construction project (Table 
7).
    Killer Whale--Little is known about killer whales that inhabit 
waters near Unalaska (Parsons et al., 2013). While it is likely that 
killer whales may appear in Dutch Harbor, given their known range and 
the availability of food, the 2015-2016 surveys saw only a small number 
(2) of marine mammals that were suspected to be killer whales (average 
monthly observation rate for these unidentified whales = 0.02). There 
are differences in the physical appearance of transient and resident 
killer whales; however, in the surveys no distinction was notated. 
Killer whale density data for the project location is not available. We 
assume, based on the best on the best available information,

[[Page 23548]]

that killer whales will be encountered in low numbers throughout the 
duration of the project. We relied on the best available information to 
estimate take of killer whales, which in this case was survey data 
collected from the 2015-2016 marine mammal surveys of Dutch Harbor as 
described above. That survey data showed killer whales are potentially 
present in the harbor only very rarely. Estimated take of killer whales 
was calculated using the equations described above, as follows:

mOR = 0.02 animals/hour
CI95 = 0.04 animals/hour
XR = 0.06 animals/hour
Estimated exposures (Level B harassment) = 0.06 * 1,470 hours = 88

    Thus we estimate that a total of 88 killer whale takes will occur 
as a result of the proposed UMC dock construction project (Table 7).
    We therefore propose to authorize the take, by Level B harassment 
only, of a total of 926 Steller sea lions (Western DPS), 470 harbor 
seals (Aleutian Islands Stock), 88 killer whales (Eastern North Pacific 
Alaska Resident and Gulf of Alaska, Aleutian Islands, and Bering Sea 
Transient Stocks), and 176 humpback whales (Central North Pacific 
Stock; Western North Pacific Stock) as a result of the proposed 
construction project. These take estimates are considered reasonable 
estimates of the number of marine mammal exposures to sound above the 
Level B harassment threshold that are likely to occur over the course 
of the project, and not the number of individual animals exposed. For 
instance, for pinnipeds that associate fishing boats in Dutch Harbor 
with reliable sources of food, there will almost certainly be some 
overlap in individuals present day-to-day depending on the number of 
vessels entering the harbor, however each instance of exposure for 
these individuals will be recorded as a separate, additional take. 
Moreover, because we anticipate that marine mammal observers will 
typically be unable to determine from field observations whether the 
same or different individuals are being exposed over the course of a 
workday, each observation of a marine mammal will be recorded as a new 
take, although an individual theoretically would only be considered as 
taken once in a given day.

 Table 7--Number of Potential Marine Mammal Incidental Takes Authorized, and Percentage of Stock Abundance, as a
                                         Result of the Proposed Project
----------------------------------------------------------------------------------------------------------------
                                                                          Underwater \1\           Percentage of
                             Species                             --------------------------------      stock
                                                                      Level A         Level B        abundance
----------------------------------------------------------------------------------------------------------------
Humpback whale..................................................               0             176             1.6
Killer whale....................................................               0              88             3.0
Steller sea lion................................................               0             926             1.9
Harbor seal.....................................................               0             470             8.1
----------------------------------------------------------------------------------------------------------------
\1\ We assume, for reasons described earlier, that no takes would occur as a result of airborne noise.

Analyses and Determinations

Negligible Impact Analysis

    NMFS has defined ``negligible impact'' in 50 CFR 216.103 as ``. . . 
an impact resulting from the specified activity that cannot be 
reasonably expected to, and is not reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival.'' 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 
Level B harassment 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 behavioral 
harassment, we consider 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 
the number and nature of estimated Level A harassment takes, the number 
of estimated mortalities, and effects on habitat.
    To avoid repetition, the discussion of our analyses applies 
generally to all the species listed in Table 7, given that the 
anticipated effects of this pile driving project on marine mammals are 
expected to be relatively similar in nature. Where there are species-
specific factors that have been considered, they are identified below.
    Pile driving activities associated with the proposed dock 
construction 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 B harassment 
(behavioral disturbance) only, from underwater sounds generated from 
pile driving. Potential takes could occur if individuals of these 
species are present in the ensonified zone when pile driving and 
removal are under way.
    The takes from Level B harassment will be due to potential 
behavioral disturbance and TTS. No injury, serious injury or mortality 
of marine mammals would be anticipated as a result of vibratory and 
impact pile driving. Except when operated at long continuous duration 
(not the case here) in the presence of marine mammals that do not move 
away, vibratory hammers do not have significant potential to cause 
injury to marine mammals due to the relatively low source levels 
produced and the lack of potentially injurious source characteristics. 
Impact pile driving produces short, sharp pulses with higher peak 
levels than vibratory driving and much sharper rise time to reach those 
peaks. The potential for injury that may otherwise result from exposure 
to noise associated with impact pile driving will effectively be 
minimized through the implementation of the planned mitigation 
measures. These measures include: The implementation of an exclusion 
(shutdown) zone, which is expected to eliminate the likelihood of 
marine mammal exposure to noise at received levels that could result in 
injury; and the use of ``soft start'' before pile driving, which is 
expected to provide marine mammals near or within the zone of potential 
injury with sufficient time to vacate the area. We believe the required 
mitigation measures, which have been successfully implemented in 
similar pile driving projects, will minimize the possibility of injury 
that may otherwise exist as a result of impact pile driving.
    The proposed activities are localized and of relatively short 
duration. The entire project area is limited to the UMC Dock area and 
its immediate surroundings. These localized and relatively short-term 
noise exposures may cause short-term behavioral modifications in harbor 
seals, Steller sea lions, killer whales, and humpback

[[Page 23549]]

whales. Moreover, the mitigation and monitoring measures, including 
injury shutdowns, soft start techniques, and multiple MMOs monitoring 
the behavioral and injury zones for marine mammal presence, are 
expected to reduce the likelihood of injury and behavior exposures. 
Additionally, no critical habitat or other specifically important areas 
for marine mammals are known to be within the ensonification areas of 
the proposed action area during the construction time frame. No 
pinniped rookeries or haul-outs are present within the project area
    The project also is not expected to have significant adverse 
effects on affected marine mammals' habitat. The project activities 
would 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.
    Effects on individuals that are taken by Level B harassment, on the 
basis of reports in the literature as well as monitoring from similar 
pile driving projects that have received incidental take authorizations 
from NMFS, will likely be limited to reactions such as increased 
swimming speeds, increased surfacing time, or decreased foraging. Most 
likely, individuals will simply move away from the sound source and be 
temporarily displaced from the area of pile driving. In response to 
vibratory driving, harbor seals have been observed to orient towards 
and sometimes move towards the sound. Repeated exposures of individuals 
to comparatively lower levels of sound that may cause Level B 
harassment are unlikely to result in hearing impairment or to 
significantly disrupt foraging behavior. Thus in this case, even 
repeated Level B harassment of some small subset of the overall stock 
is unlikely to result in any significant realized decrease in fitness 
to those individuals, and thus would not result in any adverse impact 
to the stock as a whole. Take of marine mammal species or stocks and 
their habitat will be reduced to the level of least practicable impact 
through use of mitigation measures described herein and, if sound 
produced by project activities is sufficiently disturbing, animals are 
likely to simply avoid the project area while the activity is 
occurring.
    While we are not aware of comparable construction projects in the 
project location, the pile driving activities analyzed here are similar 
to other in-water construction activities that have received incidental 
harassment authorizations previously, including a Unisea dock 
construction project in neighboring Iliuliuk Harbor, and at Naval Base 
Kitsap Bangor in Hood Canal, Washington, and at the Port of Friday 
Harbor in the San Juan Islands, which have occurred with no reported 
injuries or mortalities to marine mammals, and no known long-term 
adverse consequences to marine mammals from behavioral harassment.
    In summary, this negligible impact analysis is founded on the 
following factors: (1) The possibility of injury, serious injury, or 
mortality may reasonably be considered discountable; (2) the 
anticipated incidences of Level B harassment consist of, at worst, 
temporary modifications in behavior or potential short-term TTS; (3) 
the absence of any major rookeries and only a few isolated haulout 
areas near the project site; (4) the absence of any other known areas 
or features of special significance for foraging or reproduction within 
the project area; and (5) the presumed efficacy of planned mitigation 
measures in reducing the effects of the specified activity to the level 
of least practicable impact. In combination, we believe that these 
factors, as well as the available body of evidence from other similar 
activities, demonstrate that the potential effects of the specified 
activity will have only short-term effects on individual animals. The 
specified activity is not expected to impact rates of recruitment or 
survival and will therefore not result in population-level impacts.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the monitoring and mitigation 
measures, we find that the total marine mammal take from UMC dock 
construction activities in Dutch Harbor will have a negligible impact 
on the affected marine mammal species or stocks.

Small Numbers Analysis

    The numbers of animals authorized to be taken would be considered 
small relative to the relevant stocks or populations (1.9 percent for 
Steller sea lions, 8.1 percent for harbor seals, 1.6 percent for 
humpback whales, and 3.0 percent for killer whales) even if each 
estimated taking occurred to a new individual. However, the likelihood 
that each take would occur to a new individual is extremely low.
    Further, these takes are likely to occur only within some small 
portion of the overall regional stock. For example, of the estimated 
49,497 western DPS Steller sea lions throughout Alaska, there are 
probably no more than 300 individuals with site fidelity to the three 
haulouts located nearest to the project location, based on over twenty 
years of NMML survey data (see ``Description of Marine Mammals in the 
Area of the Specified Activity'' above). For harbor seals, NMML survey 
data suggest there are likely no more than 60 individuals that use the 
three haulouts nearest to the project location (the only haulouts in 
Unalaska Bay). Thus the estimate of take is an estimate of the number 
of anticipated exposures, rather than an estimate of the number of 
individuals that will be taken, as we expect the majority of exposures 
would be repeat exposures that would accrue to the same individuals. As 
such, the authorized takes would represent a much smaller number of 
individuals in relation to total stock sizes.
    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 mitigation and monitoring 
measures, we find that small numbers of marine mammals will be taken 
relative to the populations of the affected species or stocks.

Impact on Availability of Affected Species for Taking for Subsistence 
Uses

    Subsistence hunting and fishing is an important part of the history 
and culture of Unalaska Island. However, the number of Steller sea 
lions and harbor seals harvested in Unalaska decreased from 1994 
through 2008; in 2008, the last year for which data is available, there 
were no harbor seals reported as harvested for subsistence use and only 
three Steller sea lions reported (Wolfe et al., 2009). Data on 
pinnipeds hunted for subsistence use in Unalaska has not been collected 
since 2008. For a summary of data on pinniped harvests in Unalaska from 
1994-2008, see Section 8 of the application. Subsistence hunting for 
humpback whales and killer whales does not occur in Unalaska.
    Aside from the apparently decreasing rate of subsistence hunting in 
Unalaska, Dutch Harbor is not likely to be used for subsistence hunting 
or fishing due to its industrial nature, with several dock facilities 
located along the shoreline of the harbor. In addition, the proposed 
construction project is likely to result only in short-term, temporary 
impacts to

[[Page 23550]]

pinnipeds in the form of possible behavior changes, and is not expected 
to result in the injury or death of any marine mammal. As such, the 
proposed project is not likely to adversely impact the availability of 
any marine mammal species or stocks that may otherwise be used for 
subsistence purposes.

Endangered Species Act (ESA)

    Threatened or endangered marine mammal species with confirmed 
occurrence in the project area include the Western North Pacific DPS 
and Mexico DPS of humpback whale, and the Western DPS Steller sea lion. 
The project area occurs within critical habitat for three major Steller 
sea lion haul-outs and one rookery. The three haul-outs (Old Man Rocks, 
Unalaska/Cape Sedanka, and Akutan/Reef-Lava) are located between 
approximately 15 and 19 nautical miles from the project area. The 
closest rookery is Akutan/Cape Morgan, which is about 19 nautical miles 
from the project area.
    The NMFS Alaska Regional Office Protected Resources Division issued 
a Biological Opinion on April 19, 2017, under Section 7 of the ESA, on 
the issuance of an IHA to the COU under section 101(a)(5)(D) of the 
MMPA by the NMFS Permits and Conservation Division. The Biological 
Opinion concluded that the action is not likely to jeopardize the 
continued existence of Western DPS Steller sea lions or the Mexico DPSs 
of humpback whales, and is not likely to destroy or adversely modify 
western DPS Steller sea lion critical habitat.

National Environmental Policy Act (NEPA)

    NMFS prepared an Environmental Assessment (EA) analyzing the 
potential impacts to marine mammals from the proposed action and 
subsequently signed a Finding of No Significant Impact (FONSI). A copy 
of the EA and Finding of No Significant Impact (FONSI) is available 
upon request (see ADDRESSES).

    Dated: May 18, 2017.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2017-10536 Filed 5-22-17; 8:45 am]
 BILLING CODE 3510-22-P