Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to a Test Pile Program, 78176-78198 [2015-31620]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 80, Number 241 (Wednesday, December 16, 2015)]
[Notices]
[Pages 78176-78198]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-31620]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XE251


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to a Test Pile Program

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

ACTION: Notice; proposed incidental harassment authorization; request 
for comments.

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SUMMARY: NMFS has received a request from the Municipality of Anchorage 
(MOA), through its Port of Anchorage (POA) department, for 
authorization to take marine mammals incidental to implementation of a 
Test Pile Program, including geotechnical characterization of pile 
driving sites, near its existing facility in Anchorage, Alaska. The POA 
requests that the IHA be valid for 1 year from April 1, 2016, through 
March 31, 2017. Pursuant to the Marine Mammal Protection Act (MMPA), 
NMFS is requesting comments on its proposal to issue an incidental 
harassment authorization (IHA) to POA to incidentally take marine 
mammals, by Level B Harassment only, during the specified activity.

DATES: Comments and information must be received no later than January 
15, 2016.

ADDRESSES: Comments on the application should be addressed to Jolie 
Harrison, Chief, Permits and Conservation Division, Office of Protected 
Resources, National Marine Fisheries Service. Physical comments should 
be sent to 1315 East-West Highway, Silver Spring, MD 20910 and 
electronic comments should be sent to  ITP.Pauline@noaa.gov.
    Instructions: NMFS is not responsible for comments sent by any 
other method, to any other address or individual, or received after the 
end of the comment period. Comments received electronically, including 
all attachments, must not exceed a 25-megabyte file size. Attachments 
to electronic comments will be accepted in Microsoft Word or Excel or 
Adobe PDF file formats only. All comments received are a part of the 
public record and will generally be posted to the Internet at https://www.nmfs.noaa.gov/pr/permits/incidental/construction.htm without 
change. All personal identifying information (e.g., name, address) 
voluntarily submitted by the commenter may be publicly accessible. Do 
not submit confidential business information or otherwise sensitive or 
protected information.

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

SUPPLEMENTARY INFORMATION:

Availability

    An electronic copy of POA'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: https://www.nmfs.noaa.gov/pr/permits/incidental/construction.htm. In case of problems accessing 
these documents, please call the contact listed above.

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, feeding, or 
sheltering [Level B harassment].

Summary of Request

    On February 15, 2015, NMFS received an application from POA for the 
taking of marine mammals incidental to conducting a Test Pile Program 
as part of the Anchorage Port Modernization Project (APMP). POA 
submitted a revised application on November 23, 2015. NMFS determined 
that the application was adequate and complete on November 30, 2015. 
POA proposes to install a total of 10 test piles as part of a Test Pile 
Program to support the design of the Anchorage Port Modernization 
Project (APMP) in Anchorage, Alaska. The Test Pile Program will also be 
integrated with a hydroacoustic monitoring program to obtain data that 
can be used to evaluate potential environmental impacts and meet permit 
requirements. All pile driving is expected to be completed by July 1, 
2016. However, to accommodate unexpected project delays and other 
unforeseeable circumstances, the requested and proposed IHA period for 
the Test Pile Program is for the 1-year period from April 1, 2016, to 
March 31, 2017. Subsequent incidental take authorizations will be 
required to cover pile driving under actual construction associated 
with the APMP. Construction is anticipated to last five years.
    The use of vibratory and impact pile driving 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 the project timeframe include harbor 
seals (Phoca vitulina), Cook Inlet beluga whales (Delphinapterus 
leucas), and harbor porpoises (Phocoena phocoena). Species that may be 
encountered infrequently or rarely within the project area are killer 
whales (Orcinus orca) and Steller sea lions (Eumetopias jubatus).

Description of the Specified Activity

Overview

    The POA is modernizing its facilities through the APMP. Located 
within the MOA on Knik Arm in upper Cook Inlet (See Figure 1-1 in the 
Application), the existing 129-acre Port facility is currently 
operating at or above sustainable practicable capacity for the various 
types of cargo handled at the

[[Page 78177]]

facility. The existing infrastructure and support facilities were 
largely constructed in the 1960s. They are substantially past their 
design life, have degraded to levels of marginal safety, and are in 
many cases functionally obsolete, especially in regards to seismic 
design criteria and condition. The APMP will include construction of 
new pile-supported wharves and trestles to the south and west of the 
existing terminals, with a planned design life of 75 years.
    An initial step in the APMP is implementation of a Test Pile 
Program, the proposed action for this IHA application. The POA proposes 
to install a total of 10 test piles at the POA as part of a Test Pile 
Program to support the design of the APMP. The Test Pile Program will 
also be integrated with a hydroacoustic monitoring program to obtain 
data that can be used to evaluate potential environmental impacts and 
meet permit requirements. Proposed activities included as part of the 
Test Pile Program with potential to affect marine mammals within the 
waterways adjacent to the POA include vibratory and impact pile-driving 
operations in the project area.

Dates and Duration

    In-water work associated with the APMP Test Pile Program will begin 
no sooner than April 1, 2016, and will be completed no later than March 
31, 2017 (1 year following IHA issuance), but is expected to be 
completed by July 1, 2016. Pile driving is expected to take place over 
25 days and include 5 hours of vibratory driving and 17 hours of impact 
driving as is shown in Table 1. A 25 percent contingency has been added 
to account for delays due to weather or marine mammal shutdowns 
resulting in an estimated 6 hours of vibratory driving and 21 hours of 
impact driving over 31 days of installation. Restriking of some of the 
piles will occur two to three weeks following installation. 
Approximately 25 percent of pile driving will be conducted via 
vibratory installation, while the remaining 75 percent of pile driving 
will be conducted with impact hammers. Although each indicator pile 
test can be conducted in less than 2 hours, mobilization and setup of 
the barge at the test site will require 1 to 2 days per location and 
could be longer depending on terminal use. Additional time will be 
required for installation of sound attenuation measures, and for 
subsequent noise-mitigation monitoring. Hydroacoustic monitoring and 
installation of resonance-based systems or bubble curtains will likely 
increase the time required to install specific indicator pile from a 
few hours to a day or more.
    Within any day, the number of hours of pile driving will vary, but 
will generally be low. The number of hours required to set a pile 
initially using vibratory methods is about 30 minutes per pile, and the 
number of hours of impact driving per pile is about 1.5 hours. 
Vibratory driving for each test pile will occur on ten separate days. 
Impact driving could occur on any of the 31 days depending on a number 
of factors including weather delays and unanticipated scheduling 
issues. On some days, pile driving may occur only for an hour or less 
as bubble curtains and the containment frames are set up and 
implemented, resonance-based systems are installed, hydrophones are 
placed, pipe segments are welded, and other logistical requirements are 
handled.

                                    Table 1--Conceptual Project Schedule for Test Pile Driving, Including Estimated Number of Hours and Days for Pile Driving
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                                                                                                                     Number of
                                                                                                     Number of        hours,         Number of    Number of days  Number of days   Total number
                  Month                            Pile type                 Pile diameter             piles         vibratory     hours, impact      of pile      of  restrikes    of days of
                                                                                                                      driving         driving         driving                      pile driving
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April-July 2016.........................  Steel pipe................  48'' OD...................              10               5              17              21               4              25
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                                                                                                                                                + 25% contingency =
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                                                                                                                               6              21              26               5             31
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Notes: OD--outside diameter.

Specified Geographic Region

    The Municipality of Anchorage (MOA) is located in the lower reaches 
of Knik Arm of upper Cook Inlet. The POA sits in the industrial 
waterfront of Anchorage, just south of Cairn Point and north of Ship 
Creek (Latitude 61[deg]15' N., Longitude 149[deg]52' W.; Seward 
Meridian). Knik Arm and Turnagain Arm are the two branches of upper 
Cook Inlet, and Anchorage is located where the two Arms join (Figure 2-
1 in the Application).

Detailed Description of Activities

Pile Driving Operations
    The POA will drive ten 48-inch steel pipe indicator piles as part 
of the Test Pile Program. Installation of the piles will involve 
driving each pile with a combination of a vibratory hammer and an 
impact hammer, or with only an impact pile hammer. It is estimated that 
vibratory installation of each pile will require approximately 30 
minutes. For impact pile driving, pile installation is estimated to 
require between 80 to 100 minutes per pile, requiring 3,200 to 4,375 
pile strikes. Pile driving will be halted during installation of each 
pile as additional pile sections are added. These shutdown periods will 
range from a few hours to a day in length to accommodate welding and 
inspections.
    During the Test Pile Program, the contractor is expected to 
mobilize cranes, tugs, and floating barges, including one derrick barge 
up to 70 feet wide x 200 feet long. These barges will be moved into 
location with a tugboat. The barge will not be grounded at any time, 
but rather anchored in position using a combination of anchor lines and 
spuds (two to four, depending on the barge). Cranes will be used to 
conduct overwater work from barges, which are anticipated to remain on-
site for the duration of the Test Pile Program.
    Indicator pile-load testing involves monitoring installation of 
prototype piles as they are driven into the ground. Ten 48-inch piles 
will be driven for this test. The objective of the indicator pile tests 
is to obtain representative pile installation and capacity data near 
the area of the future pier-head line. The indicator piles will be 
vibrated and impact-driven to depths of 175 feet or more from a large 
derrick barge.
    Indicator piles will be driven adjacent to or shoreward of the 
existing wharf face. The selected locations (Figure 1-3 in the 
Application) provide representative driving conditions, and enable 
hydroacoustic measurements in water depths and locations that closely 
approximate future pile production locations.

[[Page 78178]]

    Each indicator pile will take approximately 1 to 2 hours to 
install. However, indicator test pile locations may be as much as 500 
feet apart. Therefore, the time required to mobilize equipment to drive 
each indicator pile will likely limit the number of piles driven to 
one, or perhaps two, per day.
    Indicator piles 1 and 2, which will be placed outside of the U.S. 
Army Corps of Engineer's dredging prism, will be cut off at or below 
the mudline immediately after being driven to their final depth. All 
other piles will remain in place throughout the APMP, with the 
intention of incorporating them into the new design if possible. If it 
is determined that the former indicator piles cannot be accommodated as 
APMP construction nears completion, the piles will be removed by 
cutting the piles at or below the existing mudline. These measures will 
ensure that the piles do not interfere with dredging and POA 
operations. The eight remaining indicator piles will be allowed to 
settle for two to three weeks and then will be subjected to a maximum 
of 10 restrikes each, for a total of 80 combined restrikes. No sound 
attenuation measures will be used during the restrikes, as the actual 
time spent re-striking piles will be minimal (approximately five 
minutes per pile).

Geotechnical Characterization and Schedule

    The POA proposes to complete geotechnical sampling at five 
overwater locations (Figure 1-4 in the Application) to support the 
design and construction of the APMP. Exploration equipment comprised of 
either a rotary drill rig or Cone Penetrometer Test (CPT) system will 
be used to perform the geotechnical sampling. This equipment will be 
located on the barge or wharf during the explorations. Methods used to 
conduct the sampling are described in Section 1.3.2 of the Application. 
In-water noise associated with these geotechnical sampling techniques 
is expected to be below harassment levels and will not be considered 
under this Authorization.

Hydroacoustic Monitoring

    Sound attenuation measures will be used to test for achieved 
attenuation during pile-driving operations. The POA plans to test 
attenuation associated with the use of pile cushions, resonance-based 
systems, and bubble curtains (encapsulated or confined); however, the 
currents in the project area may preclude bubble curtain use if curtain 
frames cannot be stabilized during testing. The resonance-based sound 
attenuation system is a type of system that uses noise-canceling 
resonating slats around the pile being driven to reduce noise levels 
from pile driving. The sound attenuation measures will be applied 
during specific testing periods, and then intentionally removed to 
allow comparison of sound levels during the driving of an individual 
pile. In this way, the sound signature of an individual pile can be 
compared with and without an attenuation device, avoiding the 
confounding factor of differences among piles. If sound attenuation 
measures cannot easily be added and removed, then different piles with 
and without sound attenuation measures will be compared. Data collected 
from sound attenuation testing will inform future construction of the 
APMP, which is planned as a multi-project. Details of the hydroacoustic 
monitoring plan are provided in the Application.

Description of Marine Mammals in the Area of the Specified Activity

    Marine mammals most likely to be observed within the upper Cook 
Inlet Project area include harbor seals (Phoca vitulina), beluga whales 
(Delphinapterus leucas), and harbor seals (Phocoena phocoena; NMFS 
2003). Species that may be encountered infrequently or rarely within 
the project area are killer whales (Orcinus orca) and Steller sea lions 
(Eumetopias jubatus;).

               Table 2--Marine Mammals in the Project Area
------------------------------------------------------------------------
        Species or DPS*             Abundance             Comments
------------------------------------------------------------------------
Cook Inlet beluga whale         312 \a\..........  Occurs in the project
 (Delphinapterus leucas).                           area. Listed as
                                                    Depleted under the
                                                    MMPA, Endangered
                                                    under ESA.
Killer (Orca) whale (Orcinus    2,347 Resident     Occurs rarely in the
 orca).                          587 Transient      project area. No
                                 \b\.               special status or
                                                    ESA listing.
Harbor porpoise (Phocoena       31,046 \c\.......  Occurs occasionally
 phocoena).                                         in the project area.
                                                    No special status or
                                                    ESA listing.
Harbor seal (Phoca vitulina)..  27,386 \d\.......  Occurs in the project
                                                    area. No special
                                                    status or ESA
                                                    listing.
Steller sea lion (Eumetopias    49,497 \e\.......  Occurs rarely within
 jubatus).                                          the project area.
                                                    Listed as Depleted
                                                    under the MMPA,
                                                    Endangered under
                                                    ESA.
------------------------------------------------------------------------
* DPS refers to distinct population segment under the ESA, and is
  treated as a species.
\a\ Abundance estimate for the Cook Inlet stock.
\b\ Abundance estimate for the Eastern North Pacific Alaska Resident
  stock; the estimate for the transient population is for the Gulf of
  Alaska, Aleutian Islands, and Bering Sea stock.
\c\ Abundance estimate for the Gulf of Alaska stock.
\d\ Abundance estimate for the Cook Inlet/Shelikof stock.
\e\ Abundance estimate for the Western U.S. Stock.
Sources for populations estimates: Allen and Angliss 2013, 2014, 2015.

    We have reviewed POA's detailed species descriptions, including 
life history information, for accuracy and completeness and refer the 
reader to Section 4 of POA's application instead of reprinting the 
information here. Please also refer to NMFS' Web site 
(www.nmfs.noaa.gov/pr/species/mammals) for generalized species 
accounts.
    In the species accounts provided here, we offer a brief 
introduction to the species and relevant stocks found near POA. Table 2 
presents the species and stocks of marine mammals that occur in Cook 
Inlet along with abundance estimates and likely occurrence in the 
project area.

Pinnipeds

Harbor Seal
    Harbor seals range from Baja California north along the west coasts 
of Washington, Oregon, California, British Columbia, and Southeast 
Alaska; west through the Gulf of Alaska, Prince William Sound, and the 
Aleutian Islands; and north in the Bering Sea to Cape Newenhamand the 
Pribilof Islands. There are 12 recognized stocks in Alaska. 
Distribution of the Cook Inlet/Shelikof stock extends from Seal Cape 
(Coal Bay) through all of upper and lower Cook Inlet. The Cook Inlet/
Shelikof stock is estimated at 27,386 individuals (Allen and Angliss 
2014).

[[Page 78179]]

    Harbor seals haul out on rocks, reefs, beaches, and drifting 
glacial ice (Allen and Angliss 2013). They are non-migratory; their 
local movements are associated with tides, weather, season, food 
availability, and reproduction, as well as sex and age class (Allen and 
Angliss 2013; Boveng et al. 2012; Lowry et al. 2001; Small et al. 
2003).
    Harbor seals inhabit the coastal and estuarine waters of Cook Inlet 
and are observed in both upper and lower Cook Inlet throughout most of 
the year (Boveng et al. 2012; Shelden et al. 2013). Recent research on 
satellite-tagged harbor seals observed several movement patterns within 
Cook Inlet (Boveng et al. 2012). In the fall, a portion of the harbor 
seals appeared to move out of Cook Inlet and into Shelikof Strait, 
Northern Kodiak Island, and coastal habitats of the Alaska Peninsula. 
The western coast of Cook Inlet had a higher usage than the eastern 
coast habitats, and seals generally remained south of the Forelands if 
captured in lower Cook Inlet (Boveng et al. 2012).
    The presence of harbor seals in upper Cook Inlet is seasonal. 
Harbor seals are commonly observed along the Susitna River and other 
tributaries within upper Cook Inlet during eulachon and salmon 
migrations (NMFS 2003). The major haul-out sites for harbor seals are 
located in lower Cook Inlet; however, there are a few in upper Cook 
Inlet and none in the vicinity of the project site (Montgomery et al. 
2007).
    Harbor seals are occasionally observed in Knik Arm and in the 
vicinity of the POA, primarily near the mouth of Ship Creek (Cornick et 
al. 2011; Shelden et al. 2013). During annual marine mammal surveys 
conducted by NMFS since 1994, harbor seals have been observed in Knik 
Arm and in the vicinity of the POA, however, there are no haulouts in 
the immediate area (Shelden et al. 2013).
    During construction monitoring conducted at the POA from 2005 
through 2011, harbor seals were observed from 2008 through 2011; data 
were unpublished for years 2005 through 2007 (Table 4-1 in Application) 
(Cornick et al. 2011; Cornick and Saxon-Kendall 2008, 2009, 2010; 
Markowitz and McGuire 2007; Prevel-Ramos et al. 2006). Monitoring took 
place at different times during different years. The months of March 
through December were covered during one or more of these survey years. 
Harbor seals were documented during construction monitoring efforts in 
2008. One harbor seal was sighted in Knik Arm on 13 September 2008, 
traveling north in the vicinity of the POA. In 2009, harbor seals were 
observed in the months of May through October, with the highest number 
of sightings being eight in September (Cornick et al. 2010; ICRC 
2010a). There were no harbor seals reported in 2010 from scientific 
monitoring efforts; however, 13 were reported from construction 
monitoring. In 2011, 32 sightings of harbor seals were reported during 
scientific monitoring, with a total of 57 individual harbor seals 
sighted. Harbor seals were observed in groups of one to seven 
individuals (Cornick et al. 2011). There were only two sightings of 
harbor seals during construction monitoring in 2011 (ICRC 2012).
Steller Sea Lion
    Two Distinct Population Segments (DPS) of Steller sea lions occur 
in Alaska: The western and eastern DPS. The western DPS includes 
animals that occur west of Cape Suckling, Alaska, and therefore 
includes individuals within the project area. The western DPS was 
listed under the ESA as threatened in 1990, and continued population 
decline resulted in a change in listing status to endangered in 1997. 
Since 2000, studies have documented a continued decline in the 
population in the central and western Aleutian Islands; however, the 
population east of Samalga Pass has increased and potentially is stable 
(Allen and Angliss 2014). This includes the population that inhabits 
Cook Inlet.
    It is rare for Steller sea lions to be encountered in upper Cook 
Inlet. Steller sea lions have not been documented in upper Cook Inlet 
during beluga whale aerial surveys conducted annually in June from 1994 
through 2012 (Shelden et al. 2013). During construction monitoring in 
June of 2009, a Steller sea lion was documented three times (within the 
same day) at the POA and was believed to be the same individual each 
time (ICRC 2009a).

Cetaceans

Harbor Porpoise
    In Alaska, harbor porpoises are divided into three stocks: The 
Bering Sea stock, the Southeast Alaska stock, and, relevant to this 
proposed IHA, the Gulf of Alaska stock. The Gulf of Alaska stock is 
currently estimated at 31,046 individuals (Allen and Angliss 2014). 
NMFS suggests that a finer division of stocks is likely in Alaska 
(Allen and Angliss 2014). Dahlheim et al. (2000) estimated abundance 
and density of harbor porpoises in Cook Inlet from surveys conducted in 
the early 1990s. The estimated density of animals in Cook Inlet was 7.2 
per 1,000 (km\2\), with an abundance estimate of 136 (Dahlheim et al., 
2000), indicating that only a small number use Cook Inlet. Hobbs and 
Waite (2010) estimated a harbor porpoise density in Cook Inlet of 13 
per 1,000 km\2\ from aerial beluga whale surveys in the late 1990s.
    Harbor porpoises occur in both upper and lower Cook Inlet. Small 
numbers of harbor porpoises have been consistently reported in the 
upper Cook Inlet between April and October. Several recent studies 
document monthly counts of harbor porpoises. Across these studies, the 
largest number of porpoises observed per month ranged from 12 to 129 
animals, although the latter count is considered atypical. Highest 
monthly counts include 17 harbor porpoises reported for spring through 
fall 2006 by Prevel-Ramos et al. (2008), 14 for spring of 2007 by 
Brueggeman et al. (2007), 12 for fall of 2007 by Brueggeman et al. 
(2008a), and 129 for spring through fall in 2007 by Prevel-Ramos et al. 
(2008) between Granite Point and the Susitna River during 2006 and 
2007; the reason for the spike in numbers (129) of harbor porpoises in 
the upper Cook Inlet is unclear and quite disparate with results of 
past surveys, suggesting it may be an anomaly. In the 2006 survey only 
three harbor porpoises were sighted during that month. The spike 
occurred in July, which was followed by sightings of 79 harbor 
porpoises in August, 78 in September, and 59 in October in 2007. The 
number of porpoises counted more than once was unknown, suggesting the 
actual numbers are likely smaller than reported.
    Harbor porpoises have been detected during passive acoustic 
monitoring efforts throughout Cook Inlet, with detection rates being 
especially prevalent in lower Cook Inlet. In 2009, harbor porpoises 
were documented by using passive acoustic monitoring in upper Cook 
Inlet at the Beluga River and Cairn Point (Small 2009, 2010).
    Harbor porpoises have been observed within Knik Arm during 
monitoring efforts since 2005. During POA construction from 2005 
through 2011, harbor porpoises were reported in 2009, 2010, and 2011 
(Cornick and Saxon-Kendall 2008, 2009, 2010; Cornick et al. 2011; 
Markowitz and McGuire 2007; Prevel-Ramos et al. 2006). In 2009, a total 
of 20 harbor porpoises were observed during construction monitoring 
with sightings occurring in June, July, August, October, and November. 
Harbor porpoises were observed twice in 2010, once in July and again in 
August. In 2011, POA monitoring efforts documented harbor porpoises 
five times with a total of six individuals in August, October, and 
November at the POA (Cornick et al.

[[Page 78180]]

2011). During other monitoring efforts conducted in Knik Arm, there 
were four sightings of harbor porpoises in Knik Arm in 2005 (Shelden et 
al. 2014) and a single harbor porpoise was observed within the vicinity 
of the POA in October 2007 (URS 2008).
Killer Whale
    The population of the Eastern North Pacific Alaska Resident stock 
of killer whales contains an estimated 2,347 animals and the Gulf of 
Alaska, Aleutian Islands, and Bering Sea Transient Stock includes 587 
animals (Allen and Angliss, 2014). Numbers of killer whales in Cook 
Inlet are small compared to the overall population, and most are 
recorded in lower Cook Inlet.
    Resident killer whales are primarily fish-eaters, while transients 
consume marine mammals. Both are occasionally found in Cook Inlet, 
where transient killer whales are known to feed on beluga whales, and 
resident killer whales are known to feed on anadromous fish (Shelden et 
al. 2003).
    Killer whales are rare in upper Cook Inlet, and the availability of 
prey species largely determines the likeliest times for killer whales 
to be in the area. Killer whales have been sighted in lower Cook Inlet 
17 times, with a total of 70 animals between 1993 and 2012 during 
beluga whale aerial surveys (Shelden et al. 2013); no killer whales 
were observed in upper Cook Inlet. Surveys over 20 years by Shelden et 
al. (2003) documented an increase in sightings and strandings in upper 
Cook Inlet beginning in the early 1990s. Several of these sightings and 
strandings report killer whale predation on beluga whales. Passive 
acoustic monitoring efforts throughout Cook Inlet documented killer 
whales at Beluga River, Kenai River, and Homer Spit. They were not 
encountered at any mooring within the Knik Arm. These detections were 
likely resident (fish-eating) killer whales. Transient killer whales 
(marine-mammal eating) were not believed to have been detected due to 
their propensity to move quietly through waters to track prey (Lammers 
et al. 2013; Small 2010).
    No killer whales were spotted during surveys in 2004 and 2005 by 
Funk et al. (2005), or Ireland et al. (2005). Similarly, none were 
sighted in 2007 or 2008 by Brueggeman et al. (2007, 2008a, 2008b). 
Killer whales have also not been documented during any POA construction 
or scientific monitoring (Cornick and Pinney 2011; Cornick and Saxon-
Kendall 2008; Cornick et al. 2010, 2011; ICRC 2009a, 2010a, 2011a, 
2012; Markowitz and McGuire 2007; Prevel-Ramos et al. 2006). Very few 
killer whales, if any, are expected to approach or be in the vicinity 
of the project area.
Beluga Whale
    Beluga whales appear seasonally throughout much of Alaska, except 
in the Southeast region and the Aleutian Islands. Five stocks are 
recognized in Alaska: Beaufort Sea stock, eastern Chukchi Sea stock, 
eastern Bering Sea stock, Bristol Bay stock, and Cook Inlet stock 
(Allen and Angliss 2014). The Cook Inlet stock is the most isolated of 
the five stocks, since it is separated from the others by the Alaska 
Peninsula and resides year round in Cook Inlet (Laidre et al. 2000). 
Only the Cook Inlet stock inhabits the project area.
    The Cook Inlet beluga whale Distinct Population Segment (DPS) is 
genetically (mtDNA) distinct from other Alaska populations suggesting 
the Peninsula is an effective barrier to genetic exchange (O'Corry-
Crowe et al. 1997) and that these whales may have been separated from 
other stocks at least since the last ice age. Laidre et al. (2000) 
examined data from more than 20 marine mammal surveys conducted in the 
northern Gulf of Alaska and found that sightings of belugas outside 
Cook Inlet were exceedingly rare, and these were composed of a few 
stragglers from the Cook Inlet DPS observed at Kodiak Island, Prince 
William Sound, and Yakutat Bay. Several marine mammal surveys specific 
to Cook Inlet (Laidre et al. 2000, Speckman and Piatt 2000), including 
those that concentrated on beluga whales (Rugh et al. 2000, 2005a), 
clearly indicate that this stock largely confines itself to Cook Inlet. 
There is no indication that these whales make forays into the Bering 
Sea where they might intermix with other Alaskan stocks.
    The Cook Inlet beluga DPS was originally estimated at 1,300 whales 
in 1979 (Calkins 1989) and has been the focus of management concerns 
since experiencing a dramatic decline in the 1990s. Between 1994 and 
1998 the stock declined 47 percent which was attributed to 
overharvesting by subsistence hunting. Subsistence hunting was 
estimated to annually remove 10 to 15 percent of the population during 
this period. Only five belugas have been harvested since 1999, yet the 
population has continued to decline, with the most recent estimate at 
only 312 animals (Allen and Angliss 2014). NMFS listed the population 
as ``depleted'' in 2000 as a consequence of the decline, and as 
``endangered'' under the Endangered Species Act (ESA) in 2008 after the 
population failed to show signs of recovery following a moratorium on 
subsistence harvest.
    In April 2011, NMFS designated critical habitat for the beluga 
under the ESA (Figure 4-7 in the Application). NMFS designated two 
areas of critical habitat for beluga whales in Inlet. The designation 
includes 7,800 km\2\ (3,013 mi\2\) of marine and estuarine habitat 
within Cook Inlet, encompassing approximately 1,909 km\2\ (738 mi\2\) 
in Area 1 and 5,891 km2 (2,275 mi\2\) in Area 2. From spring through 
fall, Area 1critical habitat has the highest concentration of beluga 
whales with important foraging and calving habitat. Area 2 critical 
habitat has a lower concentration of beluga whales in the spring and 
summer, but is used by belugas in the fall and winter. Critical habitat 
does not include two areas of military usage, the Eagle River Flats 
Range on Fort Richardson and military lands of JBER between Mean Higher 
High Water and Mean High Water. Additionally, the POA, the adjacent 
navigation channel, and the turning basin were excluded from critical 
habitat designation due to national security reasons (76 FR 20180).
    NMFS' Final Conservation Plan for the Cook Inlet beluga whale 
characterized the relative value of four habitats as part of the 
management and recovery strategy (NMFS 2008a). These are sites where 
beluga whales are most consistently observed, where feeding behavior 
has been documented, and where dense numbers of whales occur within a 
relatively confined area of the inlet. Type 1 Habitat is termed ``High 
Value/High Sensitivity'' and includes what NMFS believes to be the most 
important and sensitive areas of the Cook Inlet for beluga whales. Type 
2 Habitat is termed ``High Value'' and includes summer feeding areas 
and winter habitats in waters where whales typically occur in lesser 
densities or in deeper waters. Type 3 Habitat occurs in the offshore 
areas of the mid and upper inlet and also includes wintering habitat. 
Type 4 Habitat describes the remaining portions of the range of these 
whales within Cook Inlet.
    The habitat that will be directly impacted from Test Pile 
activities at the POA is considered Type 1 Habitat, although it lies 
within the zone that was excluded from any critical habitat 
designation.
    A number of studies have been conducted on the distribution of 
beluga whales in upper Cook Inlet including NMFS aerial surveys; NMFS 
data from satellite-tagged belugas (Hobbs et al. 2005); opportunistic 
sightings; baseline studies of beluga whale occurrence in Knik Arm 
conducted for the Knik Arm Bridge and Toll Authority (KABATA) (Funk et 
al. 2005); baseline studies of

[[Page 78181]]

beluga whale occurrence in Turnagain Arm conducted in preparation for 
Seward Highway improvements (Markowitz et al. 2007); marine mammal 
surveys conducted at Ladd Landing to assess a coal shipping project 
(Prevel-Ramos et al. 2008); marine mammal surveys off Granite Point, 
the Beluga River, and farther south in the inlet at North Ninilchik 
(Brueggeman et al. 2007, 2008a, 2008b); passive acoustic monitoring 
surveys throughout Cook Inlet (Lammers et al. 2013); JBER observations 
conducted within Eagle Bay and Eagle River (U.S. Army Garrison Fort 
Richardson 2009); and the scientific and construction monitoring 
program at the POA (Cornick and Pinney 2011, Cornick and Saxon-Kendall 
2007, 2008; Cornick et al. 2010, Cornick et al. 2011; ICRC 2009a, 
2010a, 2011a, 2012; Markowitz and McGuire 2007; Prevel-Ramos et al. 
2006). These data have provided a relatively good picture of the 
distribution and occurrence of beluga whales in upper Cook Inlet, 
particularly in lower Knik Arm and the project area. Findings of these 
studies are presented in detail in Section 4.5 in the Application.
    The POA conducted a NMFS-approved monitoring program for beluga 
whales and other marine mammals focused on the POA area from 2005 to 
2011 as part of their permitting requirements for the Marine Terminal 
Redevelopment Project (MTRP) (Table 4-6 in Application). Scientific 
monitoring was initiated in 2005 and was conducted by LGL Limited (LGL) 
in 2005 and 2006 (Markowitz and McGuire 2007; Prevel-Ramos et al. 
2006). Alaska Pacific University (APU) resumed scientific monitoring in 
2007 (Cornick and Saxon-Kendall 2008) and continued monitoring each 
year through 2011. Additionally, construction monitoring occurred 
during in-water construction work.
    Data on beluga whale sighting rates, grouping, behavior, and 
movement indicate that the POA is a relatively low-use area, 
occasionally visited by lone whales or small groups of whales. They are 
observed most often at low tide in the fall, peaking in late August to 
early September. Although groups with calves have been observed to 
enter the POA area, data do not suggest that the area is an important 
nursery area.
    Although the POA scientific monitoring studies indicate that the 
area is not used frequently by many beluga whales, it is apparently 
used for foraging habitat by whales traveling between lower and upper 
Knik Arm, as individuals and groups of beluga whales have been observed 
passing through the area each year during monitoring efforts (Table 4-7 
in Application). In all years, diving and traveling were the most 
common behaviors observed, with many instances of confirmed feeding. 
Sighting rates at the POA ranged from 0.05 to 0.4 whales per hour 
(Cornick and Saxon-Kendall 2008; Cornick et al. 2011; Markowitz and 
McGuire 2007; Prevel-Ramos et al. 2006), as compared to three to five 
whales per hour at Eklutna, 20 to 30 whales per hour at Birchwood, and 
three to eight whales per hour at Cairn Point (Funk et al. 2005), 
indicating that these areas are of higher use than the POA.
    Data collected annually during monitoring efforts demonstrated that 
few beluga whales were observed in July and early August; numbers of 
sightings increased in mid- August, with the highest numbers observed 
late August to mid-September. In all years, beluga whales have been 
observed to enter the project footprint while construction activities 
were taking place, including pile driving and dredging. The most 
commonly observed behaviors were traveling, diving, and suspected 
feeding. No apparent behavioral changes or reactions to in-water 
construction activities were observed by either the construction or 
scientific observers (Cornick et al. 2011).

Potential Effects of the Specified Activity on Marine Mammals and Their 
Habitat

    This section includes a summary and discussion of the ways that 
stressors, (e.g. pile driving,) and potential mitigation activities, 
associated with the proposed POA Test Pile Program may impact marine 
mammals and their habitat. The ``Estimated Take by Incidental 
Harassment'' section later in this document will include a quantitative 
analysis of the number of individuals that are expected to be taken by 
this activity. The ``Negligible Impact Analysis'' section will include 
the analysis of how this specific activity will impact marine mammals 
and will consider the content of this section, the ``Estimated Take by 
Incidental Harassment'' section, and the ``Proposed Mitigation'' 
section to draw conclusions regarding the likely impacts of this 
activity on the reproductive success or survivorship of individuals and 
from that on the affected marine mammal populations or stocks. In the 
following discussion, we provide general background information on 
sound and marine mammal hearing before considering potential effects to 
marine mammals from sound produced by pile driving.

Description of Sound Sources

    Sound travels in waves, the basic components of which are 
frequency, wavelength, velocity, and amplitude. Frequency is the number 
of pressure waves that pass by a reference point per unit of time and 
is measured in hertz (Hz) or cycles per second. Wavelength is the 
distance between two peaks of a sound wave; lower frequency sounds have 
longer wavelengths than higher frequency sounds and attenuate 
(decrease) more rapidly in shallower water. Amplitude is the height of 
the sound pressure wave or the `loudness' of a sound and is typically 
measured using the decibel (dB) scale. A dB is the ratio between a 
measured pressure (with sound) and a reference pressure (sound at a 
constant pressure, established by scientific standards). It is a 
logarithmic unit that accounts for large variations in amplitude; 
therefore, relatively small changes in dB ratings correspond to large 
changes in sound pressure. When referring to sound pressure levels 
(SPLs; the sound force per unit area), sound is referenced in the 
context of underwater sound pressure to 1 microPascal ([mu]Pa). One 
pascal is the pressure resulting from a force of one newton exerted 
over an area of one square meter. The source level (SL) represents the 
sound level at a distance of 1 m from the source (referenced to 1 
[mu]Pa). The received level is the sound level at the listener's 
position. Note that all underwater sound levels in this document are 
referenced to a pressure of 1 [mu]Pa and all airborne sound levels in 
this document are referenced to a pressure of 20 [mu]Pa.
    Root mean square (rms) is the quadratic mean sound pressure over 
the duration of an impulse. Rms is calculated by squaring all of the 
sound amplitudes, averaging the squares, and then taking the square 
root of the average (Urick, 1983). Rms accounts for both positive and 
negative values; squaring the pressures makes all values positive so 
that they may be accounted for in the summation of pressure levels 
(Hastings and Popper, 2005). This measurement is often used in the 
context of discussing behavioral effects, in part because behavioral 
effects, which often result from auditory cues, may be better expressed 
through averaged units than by peak pressures.
    When underwater objects vibrate or activity occurs, sound-pressure 
waves are created. These waves alternately compress and decompress the 
water as the sound wave travels. Underwater sound waves radiate in all 
directions away from the source (similar to ripples on the surface of a 
pond), except in cases where the source is directional.

[[Page 78182]]

The compressions and decompressions associated with sound waves are 
detected as changes in pressure by aquatic life and man-made sound 
receptors such as hydrophones.
    Even in the absence of sound from the specified activity, the 
underwater environment is typically loud due to ambient sound. Ambient 
sound is defined as environmental background sound levels lacking a 
single source or point (Richardson et al., 1995), and the sound level 
of a region is defined by the total acoustical energy being generated 
by known and unknown sources. These sources may include physical (e.g., 
waves, earthquakes, ice, atmospheric sound), biological (e.g., sounds 
produced by marine mammals, fish, and invertebrates), and anthropogenic 
sound (e.g., vessels, dredging, aircraft, construction). A number of 
sources contribute to ambient sound, including the following 
(Richardson et al., 1995):
     Wind and waves: The complex interactions between wind and 
water surface, including processes such as breaking waves and wave-
induced bubble oscillations and cavitation, are a main source of 
naturally occurring ambient noise for frequencies between 200 Hz and 50 
kHz (Mitson, 1995). In general, ambient sound levels tend to increase 
with increasing wind speed and wave height. Surf noise becomes 
important near shore, with measurements collected at a distance of 8.5 
km from shore showing an increase of 10 dB in the 100 to 700 Hz band 
during heavy surf conditions.
     Precipitation: Sound from rain and hail impacting the 
water surface can become an important component of total noise at 
frequencies above 500 Hz, and possibly down to 100 Hz during quiet 
times.
     Biological: Marine mammals can contribute significantly to 
ambient noise levels, as can some fish and shrimp. The frequency band 
for biological contributions is from approximately 12 Hz to over 100 
kHz.
     Anthropogenic: Sources of ambient noise related to human 
activity include transportation (surface vessels and aircraft), 
dredging and construction, oil and gas drilling and production, seismic 
surveys, sonar, explosions, and ocean acoustic studies. Shipping noise 
typically dominates the total ambient noise for frequencies between 20 
and 300 Hz. In general, the frequencies of anthropogenic sounds are 
below 1 kHz and, if higher frequency sound levels are created, they 
attenuate rapidly (Richardson et al., 1995). Sound from identifiable 
anthropogenic sources other than the activity of interest (e.g., a 
passing vessel) is sometimes termed background sound, as opposed to 
ambient sound.
    The sum of the various natural and anthropogenic sound sources at 
any given location and time--which comprise ``ambient'' or 
``background'' sound--depends not only on the source levels (as 
determined by current weather conditions and levels of biological and 
shipping activity) but also on the ability of sound to propagate 
through the environment. In turn, sound propagation is dependent on the 
spatially and temporally varying properties of the water column and sea 
floor, and is frequency-dependent. As a result of the dependence on a 
large number of varying factors, ambient sound levels can be expected 
to vary widely over both coarse and fine spatial and temporal scales. 
Sound levels at a given frequency and location can vary by 10-20 dB 
from day to day (Richardson et al., 1995). The result is that, 
depending on the source type and its intensity, sound from the 
specified activity may be a negligible addition to the local 
environment or could form a distinctive signal that may affect marine 
mammals.

                          Table 3--Representative Sound Levels of Anthropogenic Sources
----------------------------------------------------------------------------------------------------------------
            Sound source              Frequency range (Hz)   Underwater sound level           Reference
----------------------------------------------------------------------------------------------------------------
Small vessels......................  250-1,000.............  151 dB rms at 1 m.....  Richardson et al., 1995.
Tug docking gravel barge...........  200-1,000.............  149 dB rms at 100 m...  Blackwell and Greene, 2002.
Vibratory driving of 72-in steel     10-1,500..............  180 dB rms at 10 m....  Reyff, 2007.
 pipe pile.
Impact driving of 36-in steel pipe   10-1,500..............  195 dB rms at 10 m....  Laughlin, 2007.
 pile.
Impact driving of 66-in cast-in-     10-1,500..............  195 dB rms at 10 m....  Reviewed in Hastings and
 steel-shell (CISS) pile.                                                             Popper, 2005.
----------------------------------------------------------------------------------------------------------------

    There are two general categories of sound types: Impulse and non-
pulse. Vibratory pile driving is considered to be continuous or non-
pulsed while impact pile driving is considered to be an impulse or 
pulsed sound type. The distinction between these two sound types is 
important because they have differing potential to cause physical 
effects, particularly with regard to hearing (e.g., Ward, 1997 in 
Southall et al., 2007). Please see Southall et al., (2007) for an in-
depth discussion of these concepts.
    Pulsed sound sources (e.g., explosions, gunshots, sonic booms, 
impact pile driving) produce signals that are brief (typically 
considered to be less than one second), broadband, atonal transients 
(ANSI, 1986; Harris, 1998; NIOSH, 1998; ISO, 2003; ANSI, 2005) and 
occur either as isolated events or repeated in some succession. Pulsed 
sounds are all characterized by a relatively rapid rise from ambient 
pressure to a maximal pressure value followed by a rapid decay period 
that may include a period of diminishing, oscillating maximal and 
minimal pressures, and generally have an increased capacity to induce 
physical injury as compared with sounds that lack these features.
    Non-pulsed sounds can be tonal, narrowband, or broadband, brief or 
prolonged, and may be either continuous or non-continuous (ANSI, 1995; 
NIOSH, 1998). Some of these non-pulsed sounds can be transient signals 
of short duration but without the essential properties of pulses (e.g., 
rapid rise time). Examples of non-pulsed sounds include those produced 
by vessels, aircraft, machinery operations such as drilling or 
dredging, vibratory pile driving, and active sonar systems (such as 
those used by the U.S. Navy). The duration of such sounds, as received 
at a distance, can be greatly extended in a highly reverberant 
environment.
    The likely or possible impacts of the proposed Test Pile Program on 
marine mammals could involve both non-acoustic and acoustic stressors. 
Potential non-acoustic stressors could result from the physical 
presence of the equipment and personnel. Any impacts to marine mammals, 
however, are expected to primarily be acoustic in nature.

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals, 
and exposure to sound can have deleterious

[[Page 78183]]

effects. To appropriately assess these potential effects, it is 
necessary to understand the frequency ranges marine mammals are able to 
hear. Current data indicate that not all marine mammal species have 
equal hearing capabilities (e.g., Richardson et al., 1995; Wartzok and 
Ketten, 1999; Au and Hastings, 2008). To reflect this, Southall et al. 
(2007) recommended that marine mammals be divided into functional 
hearing groups based on measured or estimated hearing ranges on the 
basis of available behavioral data, audiograms derived using auditory 
evoked potential techniques, anatomical modeling, and other data. The 
lower and/or upper frequencies for some of these functional hearing 
groups have been modified from those designated by Southall et al. 
(2007). The functional groups and the associated frequencies are 
indicated below (note that these frequency ranges do not necessarily 
correspond to the range of best hearing, which varies by species):
     Low-frequency cetaceans (mysticetes): Functional hearing 
is estimated to occur between approximately 7 Hz and 25 kHz (extended 
from 22 kHz; Watkins, 1986; Au et al., 2006; Lucifredi and Stein, 2007; 
Ketten and Mountain, 2009; Tubelli et al., 2012);
     Mid-frequency cetaceans (larger toothed whales, beaked 
whales, and most delphinids): Functional hearing is estimated to occur 
between approximately 150 Hz and 160 kHz;
     High-frequency cetaceans (porpoises, river dolphins, and 
members of the genera Kogia and Cephalorhynchus; now considered to 
include two members of the genus Lagenorhynchus on the basis of recent 
echolocation data and genetic data [May-Collado and Agnarsson, 2006; 
Kyhn et al. 2009, 2010; Tougaard et al. 2010]): Functional hearing is 
estimated to occur between approximately 200 Hz and 180 kHz; and
     Pinnipeds in water: Functional hearing is estimated to 
occur between approximately 75 Hz to 100 kHz for Phocidae (true seals) 
and between 100 Hz and 48 kHz for Otariidae (eared seals), with the 
greatest sensitivity between approximately 700 Hz and 20 kHz. The 
pinniped functional hearing group was modified from Southall et al. 
(2007) on the basis of data indicating that phocid species have 
consistently demonstrated an extended frequency range of hearing 
compared to otariids, especially in the higher frequency range 
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth et al., 
2013).
    Of the three cetacean species likely to occur in the proposed 
project area and for which take is requested, two are classified as 
mid-frequency cetaceans (i.e., killer whale, beluga whale), and one is 
classified as a high-frequency cetacean (i.e., harbor porpoise) 
(Southall et al., 2007). Additionally, harbor seals are classified as 
members of the phocid pinnipeds in-water functional hearing group while 
Steller sea lions are grouped under the Otariid pinnipeds in-water 
functional hearing group.

Acoustic Impacts

    Potential Effects of Pile Driving Sound--The effects of sounds from 
pile driving might result in one or more of the following: Temporary or 
permanent hearing impairment, non-auditory physical or physiological 
effects, behavioral disturbance, and masking (Richardson et al., 1995; 
Gordon et al., 2004; Nowacek et al., 2007; Southall et al., 2007). The 
effects of pile driving on marine mammals are dependent on several 
factors, including the size, type, and depth of the animal; the depth, 
intensity, and duration of the pile driving sound; the depth of the 
water column; the substrate of the habitat; the standoff distance 
between the pile and the animal; and the sound propagation properties 
of the environment. Impacts to marine mammals from pile driving 
activities are expected to result primarily from acoustic pathways. As 
such, the degree of effect is intrinsically related to the received 
level and duration of the sound exposure, which are in turn influenced 
by the distance between the animal and the source. The further away 
from the source, the less intense the exposure should be. The substrate 
and depth of the habitat affect the sound propagation properties of the 
environment. Shallow environments are typically more structurally 
complex, which leads to rapid sound attenuation. In addition, 
substrates that are soft (e.g., sand) would absorb or attenuate the 
sound more readily than hard substrates (e.g., rock) which may reflect 
the acoustic wave. Soft porous substrates would also likely require 
less time to drive the pile, and possibly less forceful equipment, 
which would ultimately decrease the intensity of the acoustic source.
    In the absence of mitigation, impacts to marine species would be 
expected to result from physiological and behavioral responses to both 
the type and strength of the acoustic signature (Viada et al., 2008). 
The type and severity of behavioral impacts are more difficult to 
document due to limited studies addressing the behavioral effects of 
impulse sounds on marine mammals. Potential effects from impulse sound 
sources can range in severity from effects such as behavioral 
disturbance or tactile perception to physical discomfort, slight injury 
of the internal organs and the auditory system, or mortality (Yelverton 
et al., 1973).
    Hearing Impairment and Other Physical Effects--Marine mammals 
exposed to high intensity sound repeatedly or for prolonged periods can 
experience hearing threshold shift (TS), which is the loss of hearing 
sensitivity at certain frequency ranges (Kastak et al., 1999; Schlundt 
et al., 2000; Finneran et al., 2002, 2005). TS can be permanent (PTS), 
in which case the loss of hearing sensitivity is not recoverable, or 
temporary (TTS), in which case the animal's hearing threshold would 
recover over time (Southall et al., 2007). Marine mammals depend on 
acoustic cues for vital biological functions, (e.g., orientation, 
communication, finding prey, avoiding predators); thus, TTS may result 
in reduced fitness in survival and reproduction. However, this depends 
on the frequency and duration of TTS, as well as the biological context 
in which it occurs. TTS of limited duration, occurring in a frequency 
range that does not coincide with that used for recognition of 
important acoustic cues, would have little to no effect on an animal's 
fitness. Repeated sound exposure that leads to TTS could cause PTS. PTS 
constitutes injury, but TTS does not (Southall et al., 2007). The 
following subsections discuss in somewhat more detail the possibilities 
of TTS, PTS, and non-auditory physical effects.
    Temporary Threshold Shift--TTS is the mildest form of hearing 
impairment that can occur during exposure to a strong sound (Kryter, 
1985). While experiencing TTS, the hearing threshold rises, and a sound 
must be stronger in order to be heard. In terrestrial mammals, TTS can 
last from minutes or hours to days (in cases of strong TTS). For sound 
exposures at or somewhat above the TTS threshold, hearing sensitivity 
in both terrestrial and marine mammals recovers rapidly after exposure 
to the sound ends. Few data on sound levels and durations necessary to 
elicit mild TTS have been obtained for marine mammals, and none of the 
published data concern TTS elicited by exposure to multiple pulses of 
sound. Available data on TTS in marine mammals are summarized in 
Southall et al. (2007).
    Given the available data, the received level of a single pulse 
(with no frequency weighting) might need to be approximately 186 dB re 
1 [mu]Pa\2\-s (i.e., 186 dB sound exposure level [SEL] or approximately 
221-226 dB p-p [peak]) in order to produce brief, mild TTS.

[[Page 78184]]

Exposure to several strong pulses that each have received levels near 
190 dB rms (175-180 dB SEL) might result in cumulative exposure of 
approximately 186 dB SEL and thus slight TTS in a small odontocete, 
assuming the TTS threshold is (to a first approximation) a function of 
the total received pulse energy.
    The above TTS information for odontocetes is derived from studies 
on the bottlenose dolphin (Tursiops truncatus) and beluga whale. There 
is no published TTS information for other species of cetaceans. 
However, preliminary evidence from a harbor porpoise exposed to pulsed 
sound suggests that its TTS threshold may have been lower (Lucke et 
al., 2009). As summarized above, data that are now available imply that 
TTS is unlikely to occur unless odontocetes are exposed to pile driving 
pulses stronger than 180 dB re 1 [mu]Pa rms.
    Permanent Threshold Shift--When PTS occurs, there is physical 
damage to the sound receptors in the ear. In severe cases, there can be 
total or partial deafness, while in other cases the animal has an 
impaired ability to hear sounds in specific frequency ranges (Kryter, 
1985). There is no specific evidence that exposure to pulses of sound 
can cause PTS in any marine mammal. However, given the possibility that 
mammals close to a sound source can incur TTS, it is possible that some 
individuals might incur PTS. Single or occasional occurrences of mild 
TTS are not indicative of permanent auditory damage, but repeated or 
(in some cases) single exposures to a level well above that causing TTS 
onset might elicit PTS.
    Relationships between TTS and PTS thresholds have not been studied 
in marine mammals but are assumed to be similar to those in humans and 
other terrestrial mammals, based on anatomical similarities. PTS might 
occur at a received sound level at least several decibels above that 
inducing mild TTS if the animal were exposed to strong sound pulses 
with rapid rise time. Based on data from terrestrial mammals, a 
precautionary assumption is that the PTS threshold for impulse sounds 
(such as pile driving pulses as received close to the source) is at 
least 6 dB higher than the TTS threshold on a peak-pressure basis and 
probably greater than 6 dB (Southall et al., 2007). On an SEL basis, 
Southall et al. (2007) estimated that received levels would need to 
exceed the TTS threshold by at least 15 dB for there to be risk of PTS. 
Thus, for cetaceans, Southall et al. (2007) estimate that the PTS 
threshold might be an M-weighted SEL (for the sequence of received 
pulses) of approximately 198 dB re 1 [mu]Pa\2\-s (15 dB higher than the 
TTS threshold for an impulse). Given the higher level of sound 
necessary to cause PTS as compared with TTS, it is considerably less 
likely that PTS could occur.
    Although no marine mammals have been shown to experience TTS or PTS 
as a result of being exposed to pile driving activities, captive 
bottlenose dolphins and beluga whales exhibited changes in behavior 
when exposed to strong pulsed sounds (Finneran et al., 2000, 2002, 
2005). The animals tolerated high received levels of sound before 
exhibiting aversive behaviors. Experiments on a beluga whale showed 
that exposure to a single watergun impulse at a received level of 207 
kPa (30 psi) p-p, which is equivalent to 228 dB p-p, resulted in a 7 
and 6 dB TTS in the beluga whale at 0.4 and 30 kHz, respectively. 
Thresholds returned to within 2 dB of the pre-exposure level within 
four minutes of the exposure (Finneran et al., 2002). Although the 
source level of pile driving from one hammer strike is expected to be 
much lower than the single watergun impulse cited here, animals being 
exposed for a prolonged period to repeated hammer strikes could receive 
more sound exposure in terms of SEL than from the single watergun 
impulse (estimated at 188 dB re 1 [mu]Pa\2\-s) in the aforementioned 
experiment (Finneran et al., 2002). However, in order for marine 
mammals to experience TTS or PTS, the animals have to be close enough 
to be exposed to high intensity sound levels for a prolonged period of 
time. Based on the best scientific information available, these SPLs 
are far below the thresholds that could cause TTS or the onset of PTS.
    Non-auditory Physiological Effects--Non-auditory physiological 
effects or injuries that theoretically might occur in marine mammals 
exposed to strong underwater sound include stress, neurological 
effects, bubble formation, resonance effects, and other types of organ 
or tissue damage (Cox et al., 2006; Southall et al., 2007). Studies 
examining such effects are limited. In general, little is known about 
the potential for pile driving to cause auditory impairment or other 
physical effects in marine mammals. Available data suggest that such 
effects, if they occur at all, would presumably be limited to short 
distances from the sound source and to activities that extend over a 
prolonged period. The available data do not allow identification of a 
specific exposure level above which non-auditory effects can be 
expected (Southall et al., 2007) or any meaningful quantitative 
predictions of the numbers (if any) of marine mammals that might be 
affected in those ways. Marine mammals that show behavioral avoidance 
of pile driving, including some odontocetes and some pinnipeds, are 
especially unlikely to incur auditory impairment or non-auditory 
physical effects.

Disturbance Reactions

    Disturbance includes a variety of effects, including subtle changes 
in behavior, more conspicuous changes in activities, and displacement. 
Behavioral responses to sound are highly variable and context-specific 
and reactions, if any, depend on species, state of maturity, 
experience, current activity, reproductive state, auditory sensitivity, 
time of day, and many other factors (Richardson et al., 1995; Wartzok 
et al., 2003; Southall et al., 2007).
    Habituation can occur when an animal's response to a stimulus wanes 
with repeated exposure, usually in the absence of unpleasant associated 
events (Wartzok et al., 2003). Animals are most likely to habituate to 
sounds that are predictable and unvarying. The opposite process is 
sensitization, when an unpleasant experience leads to subsequent 
responses, often in the form of avoidance, at a lower level of 
exposure. Behavioral state may affect the type of response as well. For 
example, animals that are resting may show greater behavioral change in 
response to disturbing sound levels than animals that are highly 
motivated to remain in an area for feeding (Richardson et al., 1995; 
NRC, 2003; Wartzok et al., 2003).
    Controlled experiments with captive marine mammals showed 
pronounced behavioral reactions, including avoidance of loud sound 
sources (Ridgway et al., 1997; Finneran et al., 2003). Observed 
responses of wild marine mammals to loud pulsed sound sources 
(typically seismic guns or acoustic harassment devices, but also 
including pile driving) have been varied but often consist of avoidance 
behavior or other behavioral changes suggesting discomfort (Morton and 
Symonds, 2002; Thorson and Reyff, 2006; see also Gordon et al., 2004; 
Wartzok et al., 2003; Nowacek et al., 2007). Responses to continuous 
sound, such as vibratory pile installation, have not been documented as 
well as responses to pulsed sounds.
    With both types of pile driving, it is likely that the onset of 
pile driving could result in temporary, short term changes in an 
animal's typical behavior and/or avoidance of the affected area. These 
behavioral changes may include (Richardson et al., 1995): changing 
durations of surfacing and dives,

[[Page 78185]]

number of blows per surfacing, or moving direction and/or speed; 
reduced/increased vocal activities; changing/cessation of certain 
behavioral activities (such as socializing or feeding); visible startle 
response or aggressive behavior (such as tail/fluke slapping or jaw 
clapping); avoidance of areas where sound sources are located; and/or 
flight responses (e.g., pinnipeds flushing into water from haul-outs or 
rookeries). Pinnipeds may increase their haul-out time, possibly to 
avoid in-water disturbance (Thorson and Reyff, 2006).
    The biological significance of many of these behavioral 
disturbances is difficult to predict, especially if the detected 
disturbances appear minor. However, the consequences of behavioral 
modification could be expected to be biologically significant if the 
change affects growth, survival, or reproduction. Significant 
behavioral modifications that could potentially lead to effects on 
growth, survival, or reproduction include:
     Drastic changes in diving/surfacing patterns (such as 
those thought to cause beaked whale stranding due to exposure to 
military mid-frequency tactical sonar);
     Habitat abandonment due to loss of desirable acoustic 
environment; and
     Cessation of feeding or social interaction.
    The onset of behavioral disturbance from anthropogenic sound 
depends on both external factors (characteristics of sound sources and 
their paths) and the specific characteristics of the receiving animals 
(hearing, motivation, experience, demography) and is difficult to 
predict (Southall et al., 2007).
    Auditory Masking--Natural and artificial sounds can disrupt 
behavior by masking, or interfering with, a marine mammal's ability to 
hear other sounds. Masking occurs when the receipt of a sound is 
interfered with by another coincident sound at similar frequencies and 
at similar or higher levels. Chronic exposure to excessive, though not 
high-intensity, sound could cause masking at particular frequencies for 
marine mammals that utilize sound for vital biological functions. 
Masking can interfere with detection of acoustic signals such as 
communication calls, echolocation sounds, and environmental sounds 
important to marine mammals. Therefore, under certain circumstances, 
marine mammals whose acoustical sensors or environment are being 
severely masked could also be impaired from maximizing their 
performance fitness in survival and reproduction. If the coincident 
(masking) sound were anthropogenic, it could be potentially harassing 
if it disrupted hearing-related behavior. It is important to 
distinguish TTS and PTS, which persist after the sound exposure, from 
masking, which occurs only during the sound exposure. Because masking 
(without resulting in TS) is not associated with abnormal physiological 
function, it is not considered a physiological effect, but rather a 
potential behavioral effect.
    Masking occurs at the frequency band which the animals utilize so 
the frequency range of the potentially masking sound is important in 
determining any potential behavioral impacts. Because sound generated 
from in-water vibratory pile driving is mostly concentrated at low 
frequency ranges, it may have less effect on high frequency 
echolocation sounds made by porpoises. However, lower frequency man-
made sounds are more likely to affect detection of communication calls 
and other potentially important natural sounds such as surf and prey 
sound. It may also affect communication signals when they occur near 
the sound band and thus reduce the communication space of animals 
(e.g., Clark et al., 2009) and cause increased stress levels (e.g., 
Foote et al., 2004; Holt et al., 2009).
    Masking affects both senders and receivers of the signals and can 
potentially have long-term chronic effects on marine mammal species and 
populations. Recent research suggests that low frequency ambient sound 
levels have increased by as much as 20 dB (more than three times in 
terms of SPL) in the world's ocean from pre-industrial periods, and 
that most of these increases are from distant shipping (Hildebrand, 
2009). All anthropogenic sound sources, such as those from vessel 
traffic, pile driving, and dredging activities, contribute to the 
elevated ambient sound levels, thus intensifying masking.
    Vibratory pile driving is relatively short-term, with rapid 
oscillations occurring for 10 to 30 minutes per installed pile. It is 
possible that vibratory pile driving resulting from this proposed 
action may mask acoustic signals important to the behavior and survival 
of marine mammal species, but the short-term duration and limited 
affected area would result in insignificant impacts from masking.
    Impacts of geotechnical Investigations--Limited data exist 
regarding underwater noise levels associated with Standard Penetration 
Test (SPT) or Cone Penetrometer Test (CPT) investigations, and no data 
exist for SPT or CPT geotechnical investigations in Cook Inlet or Knik 
Arm. Geotechnical drilling for the POA, which includes SPT or CPT 
sampling, will be of smaller size and scale than the full-scale 
drilling operations described below. Hydroacoustic tests conducted by 
Illingworth & Rodkin (2014a) in May 2013 revealed that underwater noise 
levels from large drilling operations were below ambient noise levels. 
On two different occasions, Sound Source Verification (SSV) 
measurements were made of conductor pipe drilling, with and without 
other noise-generating activities occurring simultaneously. Drilling 
sounds could not be measured or heard above the other sounds emanating 
from the rig. The highest sound levels measured that were emanating 
from the rig during drilling were 128 dB rms, and they were attributed 
to a different sound source (Illingworth & Rodkin 2014a). Therefore, 
NMFS will assume that sound impacts from geotechnical investigations 
will not rise to Level B harassment thresholds.
    Acoustic Effects, Airborne--Marine mammals that occur in the 
project area could be exposed to airborne sounds associated with pile 
driving that have the potential to cause harassment, depending on their 
distance from pile driving activities. Airborne pile driving sound 
would not impact cetaceans because sound from atmospheric sources does 
not transmit well underwater (Richardson et al., 1995); thus, airborne 
sound may only be an issue for pinnipeds either hauled-out or looking 
with heads above water in the project area. Most likely, airborne sound 
would cause behavioral responses similar to those discussed above in 
relation to underwater sound. For instance, anthropogenic sound could 
cause hauled-out pinnipeds to exhibit changes in their normal behavior, 
such as reduction in vocalizations, or cause them to temporarily 
abandon their habitat and move further from the source. Studies by 
Blackwell et al. (2004) and Moulton et al. (2005) indicate a tolerance 
or lack of response to unweighted airborne sounds as high as 112 dB 
peak and 96 dB rms.

Vessel Interaction

    Besides being susceptible to vessel strikes, cetacean and pinniped 
responses to vessels may result in behavioral changes, including 
greater variability in the dive, surfacing, and respiration patterns; 
changes in vocalizations; and changes in swimming speed or direction 
(NRC 2003). There will be a temporary and localized increase in vessel 
traffic during construction. A maximum of three work barges will be 
present at any time during the in-water and over water work. The barges 
will be located near

[[Page 78186]]

each other where construction is occurring. Additionally, the floating 
pier will be tugged into position prior to installation.

Potential Effects on Marine Mammal Habitat

    The primary potential impacts to marine mammal habitat are 
associated with elevated sound levels produced by impact and vibratory 
pile driving in the area. However, other potential impacts to the 
surrounding habitat from physical disturbance are also possible.
    Potential Pile Driving Effects on Prey--Test Pile activities would 
produce continuous (i.e., vibratory pile driving) sounds and pulsed 
(i.e. impact driving) sounds. Fish react to sounds that are especially 
strong and/or intermittent low-frequency sounds. Short duration, sharp 
sounds can cause overt or subtle changes in fish behavior and local 
distribution. Hastings and Popper (2005) identified several studies 
that suggest fish may relocate to avoid certain areas of sound energy. 
Additional studies have documented effects of pile driving on fish, 
although several are based on studies in support of large, multiyear 
bridge construction projects (e.g., Scholik and Yan, 2001, 2002; Popper 
and Hastings, 2009). Sound pulses at received levels of 160 dB may 
cause subtle changes in fish behavior. SPLs of 180 dB may cause 
noticeable changes in behavior (Pearson et al., 1992; Skalski et al., 
1992). SPLs of sufficient strength have been known to cause injury to 
fish and fish mortality.
    The area likely impacted by the proposed Test Pile Program is 
relatively small compared to the available habitat in Knik Arm. Due to 
the lack of definitive studies on how the proposed Test Pile Program 
might affect prey availability for marine mammals there is uncertainty 
to the impact analysis. However, this uncertainty will be mitigated due 
to the low quality and quantity of marine habitat, low abundance and 
seasonality of salmonids and other prey, and mitigation measures 
already in place to reduce impacts to fish. The most likely impact to 
fish from the proposed Test Pile Program will be temporary behavioral 
avoidance of the immediate area. In general, the nearer the animal is 
to the source the higher the likelihood of high energy and a resultant 
effect (such as mild, moderate, mortal injury). Affected fish would 
represent only a small portion of food available to marine mammals in 
the area. The duration of fish avoidance of this area after pile 
driving stops is unknown, but a rapid return to normal recruitment, 
distribution, and behavior is anticipated. Any behavioral avoidance by 
fish of the disturbed area will still leave significantly large areas 
of fish and marine mammal foraging habitat in Knik Arm. Therefore, the 
impacts on marine mammal prey during the proposed Test Pile Program are 
expected to be minor.

Effects to Foraging Habitat

    The Cook Inlet beluga whale is the only marine mammal species in 
the project area that has critical habitat designated in Cook Inlet. 
NMFS designated critical habitat in portions of Cook Inlet, including 
Knik Arm. NMFS noted that Knik Arm is Type 1 habitat for the Cook Inlet 
beluga whale, which means it is the most valuable, used intensively by 
beluga whales from spring through fall for foraging and nursery 
habitat. However, the area in the immediate vicinity of POA has been 
excluded from critical habitat designation. The waters around POA are 
subject to heavy vessel traffic and the shoreline is built up and 
industrialized, resulting in habitat of marginal quality.
    The proposed Test Pile Program will not result in permanent impacts 
to habitats used by marine mammals. Pile installation may temporarily 
increase turbidity resulting from suspended sediments. Any increases 
would be temporary, localized, and minimal. POA must comply with state 
water quality standards during these operations by limiting the extent 
of turbidity to the immediate project area. In general, turbidity 
associated with pile installation is localized to about a 25-foot 
radius around the pile (Everitt et al. 1980). Cetaceans are not 
expected to be close enough to the project site driving areas to 
experience effects of turbidity, and any pinnipeds will be transiting 
the terminal area and could avoid localized areas of turbidity. 
Therefore, the impact from increased turbidity levels is expected to be 
discountable to marine mammals. The proposed Test Pile Program will 
result in temporary changes in the acoustic environment. Marine mammals 
may experience a temporary loss of habitat because of temporarily 
elevated noise levels. The most likely impact to marine mammal habitat 
would be from pile-driving effects on marine mammal prey at and near 
the POA and minor impacts to the immediate substrate during 
installation of piles during the proposed Test Pile Program. Long-term 
effects of any prey displacements are not expected to affect the 
overall fitness of the Cook Inlet beluga whale population or its 
recovery; effects will be minor and will terminate after cessation of 
the proposed Test Pile Program.

Proposed Mitigation Measures

    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. NMFS regulations require applicants for incidental 
take authorizations to include information about the availability and 
feasibility (economic and technological) of equipment, methods, and 
manner of conducting such activity or other means of effecting the 
least practicable adverse impact upon the affected species or stocks, 
their habitat. 50 CFR 216.104(a)(11). For the proposed project, POA 
worked with NMFS and proposed the following mitigation measures to 
minimize the potential impacts to marine mammals in the project 
vicinity. The primary purposes of these mitigation measures are to 
minimize sound levels from the activities, and to monitor marine 
mammals within designated zones of influence corresponding to NMFS' 
current Level A and B harassment thresholds which are depicted in Table 
5 found later in the Estimated Take by Incidental Harassment section.
    In addition to the measures described later in this section, POA 
would employ the following standard mitigation measures:
    (a) Conduct briefings between construction supervisors and crews, 
marine mammal monitoring team, and POA staff prior to the start of all 
pile driving activity, and when new personnel join the work, in order 
to explain responsibilities, communication procedures, marine mammal 
monitoring protocol, and operational procedures.
    (b) For in-water heavy machinery work other than pile driving 
(using, e.g., standard barges, tug boats, barge-mounted excavators, or 
clamshell equipment used to place or remove material), if a marine 
mammal comes within 10 m, operations shall cease and vessels shall 
reduce speed to the minimum level required to maintain steerage and 
safe working conditions. This type of work could include the following 
activities: (1) Movement of the barge to the pile location or (2) 
positioning of the pile on the substrate via a crane (i.e., stabbing 
the pile).
    Time Restrictions--Work would occur only during daylight hours, 
when visual monitoring of marine mammals can be conducted.

[[Page 78187]]

    Establishment of Disturbance Zone or Zone of Influence--Disturbance 
zones or zones of influence (ZOI) are the areas in which SPLs equal or 
exceed 160 dB rms for impact driving and 125 dB rms for vibratory 
driving. Note that 125 dB has been established as the Level B 
harassment zone isopleth for vibratory driving since ambient noise 
levels near the POA are likely to be above 120 dB RMS and this value 
has been used previously as a threshold in this area. Disturbance zones 
provide utility for monitoring conducted for mitigation purposes (i.e., 
shutdown zone monitoring) by establishing monitoring protocols for 
areas adjacent to the shutdown zones. Monitoring of disturbance zones 
enables observers to be aware of and communicate the presence of marine 
mammals in the project area but outside the shutdown zone and thus 
prepare for potential shutdowns of activity. However, the primary 
purpose of disturbance zone monitoring is for documenting incidents of 
Level B harassment; disturbance zone monitoring is discussed in greater 
detail later (see ``Proposed Monitoring and Reporting''). Nominal 
radial distances for disturbance zones are shown in Table 5. Given the 
size of the disturbance zone for vibratory pile driving, it is 
impossible to guarantee that all animals would be observed or to make 
comprehensive observations of fine-scale behavioral reactions to sound. 
We discuss monitoring objectives and protocols in greater depth in 
``Proposed Monitoring and Reporting.''
    In order to document observed incidents of harassment, monitors 
record all marine mammal observations, regardless of location. The 
observer's location, as well as the location of the pile being driven, 
is known from a GPS. The location of the animal is estimated as a 
distance from the observer, which is then compared to the location from 
the pile and the ZOIs for relevant activities (i.e., pile 
installation). This information may then be used to extrapolate 
observed takes to reach an approximate understanding of actual total 
takes.
    Soft Start--The use of a soft start procedure is believed to 
provide additional protection to marine mammals by warning or providing 
a chance to leave the area prior to the hammer operating at full 
capacity, and typically involves a requirement to initiate sound from 
the hammer for 15 seconds at reduced energy followed by a waiting 
period. This procedure is repeated two additional times. It is 
difficult to specify the reduction in energy for any given hammer 
because of variation across drivers and, for impact hammers, the actual 
number of strikes at reduced energy will vary because operating the 
hammer at less than full power results in ``bouncing'' of the hammer as 
it strikes the pile, resulting in multiple ``strikes.'' The project 
will utilize soft start techniques for both impact and vibratory pile 
driving. POA will initiate sound from vibratory hammers for fifteen 
seconds at reduced energy followed by a 1 minute waiting period, with 
the procedure repeated two additional times. For impact driving, we 
require an initial set of three strikes from the impact hammer at 
reduced energy, followed by a thirty-second waiting period, then two 
subsequent three strike sets. Soft start will be required at the 
beginning of each day's pile driving work and at any time following a 
cessation of pile driving of 20 minutes or longer (specific to either 
vibratory or impact driving).

Monitoring and Shutdown for Pile Driving

    The following measures would apply to POA's mitigation through 
shutdown and disturbance zones:
    Shutdown Zone--For all pile driving activities, POA will establish 
a shutdown zone. Shutdown zones are intended to contain the area in 
which SPLs equal or exceed the 180/90 dB rms acoustic injury criteria, 
with the purpose being to define an area within which shutdown of 
activity would occur upon sighting of a marine mammal (or in 
anticipation of an animal entering the defined area), thus preventing 
injury of marine mammals. POA, however, will implement a minimum 
shutdown zone of 100 m radius for all marine mammals around all 
vibratory and impact pile activity. These precautionary measures would 
also further reduce the possibility of auditory injury and behavioral 
impacts as well as limit the unlikely possibility of injury from direct 
physical interaction with construction operations.
    Shutdown for Large Groups--To reduce the chance of POA reaching or 
exceeding authorized take, and to minimize harassment to beluga whales, 
in-water pile driving operations will be shut down if a group of five 
or more beluga whales is sighted within or approaching the Level B 
harassment 160 dB and 125 dB disturbance zones, as appropriate. If the 
group is not re-sighted within 20 minutes, pile driving will resume.
    Shutdown for Beluga Whale Calves--Beluga whale calves are likely 
more susceptible to loud anthropogenic noise than juveniles or adults. 
If a calf is sighted within or approaching a harassment zone, in-water 
pile driving will cease and will not be resumed until the calf is 
confirmed to be out of the harassment zone and on a path away from the 
pile driving. If a calf or the group with a calf is not re-sighted 
within 20 minutes, pile driving will resume.
    Visual Marine Mammal Observation--POA will collect sighting data 
and behavioral responses to construction for marine mammal species 
observed in the region of activity during the period of activity. All 
observers will be trained in marine mammal identification and behaviors 
and are required to have no other construction-related tasks while 
conducting monitoring. POA will monitor the shutdown zone and 
disturbance zone before, during, and after pile driving, with observers 
located at the best practicable vantage points. Based on our 
requirements, the Marine Mammal Monitoring Plan would implement the 
following procedures for pile driving:
     Four MMOs will work concurrently in rotating shifts to 
provide full coverage for marine mammal monitoring during in-water pile 
installation activities for the Test Pile Program. MMOs will work in 
four-person teams to increase the probability of detecting marine 
mammals and to confirm sightings. Three MMOs will scan the Level A and 
Level B harassment zones surrounding pile-driving activities for marine 
mammals by using big eye binoculars (25X), hand-held binoculars (7X), 
and the naked eye. One MMO will focus on the Level A harassment zone 
and two others will scan the Level B zone. Four MMOs will rotate 
through these three active positions every 30 minutes to reduce eye 
strain and increase observer alertness. The fourth MMO will record data 
on the computer, a less-strenuous activity that will provide the 
opportunity for some rest. A theodolite will also be available for use.
     In order to more effectively monitor the larger Level B 
harassment zone for vibratory pile driving, one or more MMOs shall be 
placed on one of the vessels used for hydroacoustic monitoring, which 
will be stationed offshore.
     Before the Test Pile Program commences, MMOs and POA 
authorities will meet to determine the most appropriate observation 
platform(s) for monitoring during pile driving. Considerations will 
include:
    [cir] Height of the observation platform, to maximize field of view 
and distance
    [cir] Ability to see the shoreline, along which beluga whales 
commonly travel

[[Page 78188]]

    [cir] Safety of the MMOs, construction crews, and other people 
present at the POA
    [cir] Minimizing interference with POA activities
Height and location of an observation platform are critical to ensuring 
that MMOs can adequately observe the harassment zone during pile 
installation. The platform should be mobile and able to be relocated to 
maintain maximal viewing conditions as the construction site shifts 
along the waterfront. Past monitoring efforts at the POA took place 
from a platform built on top of a cargo container or a platform raised 
by an industrial scissor lift. A similar shore-based, raised, mobile 
observation platform will likely be used for the Test Pile Program.
     POA will monitor a 100-meter ``shutdown'' zone during all 
pile-driving operations (vibratory and impact) to prevent Level A take 
by injury. If a marine mammal passes the 100-meter shutdown zone prior 
to the cessation of in-water pile installation but does not reach the 
Level A harassment zone, which is 14 m for pinnipeds 63 m for 
cetaceans, there is no Level A take.
     MMOs will begin observing for marine mammals within the 
Level A and Level B harassment zones for 20 minutes before ``the soft 
start'' begins. If a marine mammal(s) is present within the 100-meter 
shutdown zone prior to the ``soft start'' or if marine mammal occurs 
during ``soft start'' pile driving will be delayed until the animal(s) 
leaves the 100-meter shutdown zone. Pile driving will resume only after 
the MMOs have determined, through sighting or by waiting 20 minutes, 
that the animal(s) has moved outside the 100-meter shutdown zone. After 
20 minutes, when the MMOs are certain that the 100-meter shutdown zone 
is clear of marine mammals, they will authorize the soft start to 
begin.
     If a marine mammal is traveling along a trajectory that 
could take it into the Level B harassment zone, the MMO will record the 
marine mammal(s) as a ``take'' upon entering the Level B harassment 
zone. While the animal remains within the Level B harassment zone, that 
pile segment will be completed without cessation, unless the animal 
approaches the 100-meter shutdown zone, at which point the MMO will 
authorize the immediate shutdown of in-water pile driving before the 
marine mammal enters the 100- meter shutdown zone. Pile driving will 
resume only once the animal has left the 100-meter shutdown zone on its 
own or has not been resighted for a period of 20 minutes.
     Beluga whale calves are likely more susceptible to loud 
anthropogenic noise than juveniles or adults. If a calf is sighted 
approaching a harassment zone, in-water pile driving will cease and not 
resume until the calf is confirmed to be out of the harassment zone and 
on a path away from the pile driving. If a calf or the group with a 
calf is not re-sighted within 20 minutes, pile driving may resume.
     If waters exceed a sea-state which restricts the 
observers' ability to make observations within the marine mammal 
shutdown zone (the 100 meter radius) (e.g. excessive wind or fog), 
impact pile installation will cease until conditions allow the 
resumption of monitoring.
     The waters will be scanned 20 minutes prior to commencing 
pile driving at the beginning of each day, and prior to commencing pile 
driving after any stoppage of 20 minutes or greater. If marine mammals 
enter or are observed within the designated marine mammal buffer zone 
(the 100m radius) during or 20 minutes prior to pile driving, the 
monitors will notify the on-site construction manager to not begin 
until the animal has moved outside the designated radius.
     The waters will continue to be scanned for at least 20 
minutes after pile driving has completed each day.

Mitigation Conclusions

    NMFS has carefully evaluated the applicant's proposed mitigation 
measures and considered a range of other measures in the context of 
ensuring that NMFS prescribes the means of affecting 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:
     The manner in which, and the degree to which, the 
successful implementation of the measure is expected to minimize 
adverse impacts to marine mammals
     The proven or likely efficacy of the specific measure to 
minimize adverse impacts as planned
     The practicability of the measure for applicant 
implementation,
    Any mitigation measure(s) prescribed by NMFS should be able to 
accomplish, have a reasonable likelihood of accomplishing (based on 
current science), or contribute to the accomplishment of one or more of 
the general goals listed below:
    1. Avoidance or minimization of injury or death of marine mammals 
wherever possible (goals 2, 3, and 4 may contribute to this goal).
    2. A reduction in the numbers of marine mammals (total number or 
number at biologically important time or location) exposed to received 
levels of pile driving, or other activities expected to result in the 
take of marine mammals (this goal may contribute to 1, above, or to 
reducing harassment takes only).
    3. A reduction in the number of times (total number or number at 
biologically important time or location) individuals would be exposed 
to received levels of pile driving, or other activities expected to 
result in the take of marine mammals (this goal may contribute to 1, 
above, or to reducing harassment takes only).
    4. A reduction in the intensity of exposures (either total number 
or number at biologically important time or location) to received 
levels of pile driving, or other activities expected to result in the 
take of marine mammals (this goal may contribute to a, above, or to 
reducing the severity of harassment takes only).
    5. Avoidance or minimization of adverse effects to marine mammal 
habitat, paying special attention to the food base, activities that 
block or limit passage to or from biologically important areas, 
permanent destruction of habitat, or temporary destruction/disturbance 
of habitat during a biologically important time.
    6. For monitoring directly related to mitigation--an increase in 
the probability of detecting marine mammals, thus allowing for more 
effective implementation of the mitigation.
    Based on our evaluation of the applicant's proposed measures, as 
well as other measures considered by NMFS, our preliminarily 
determination is that the proposed mitigation measures provide the 
means of effecting the least practicable impact on marine mammals 
species or stocks and their habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance.

Proposed Monitoring and Reporting

    In order to issue an ITA 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 ITAs 
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

[[Page 78189]]

action area. POA submitted a marine mammal monitoring plan as part of 
the IHA application. It can be found at https://www.nmfs.noaa.gov/pr/permits/incidental/construction.htm.
    Monitoring measures prescribed by NMFS should accomplish one or 
more of the following general goals:
    1. An increase in the probability of detecting marine mammals, both 
within the mitigation zone (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 levels of pile driving that we associate with 
specific adverse effects, such as behavioral harassment, TTS, or PTS;
    3. An increase in our understanding of how marine mammals respond 
to stimuli expected to result in take and how anticipated adverse 
effects on individuals (in different ways and to varying degrees) may 
impact the population, species, or stock (specifically through effects 
on annual rates of recruitment or survival) through any of the 
following methods:
    [ssquf] Behavioral observations in the presence of stimuli compared 
to observations in the absence of stimuli (need to be able to 
accurately predict received level, distance from source, and other 
pertinent information);
    [ssquf] Physiological measurements in the presence of stimuli 
compared to observations in the absence of stimuli (need to be able to 
accurately predict received level, distance from source, and other 
pertinent information);
    [ssquf] 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; and
    5. An increase in our understanding of the effectiveness of certain 
mitigation and monitoring measures.

Acoustic Monitoring

    The POA will conduct acoustic monitoring for impact pile driving to 
determine the actual distances to the 190 dB re 1[mu]Pa rms, 180 dB re 
1[mu]Pa rms, and 160 dB re 1[mu]Pa rms isopleths, which are used by 
NMFS to define the Level A injury and Level B harassment zones for 
pinnipeds and cetaceans for impact pile driving. Encapsulated bubble 
curtains and resonance-based attenuation systems will be tested during 
installation of some piles to determine their relative effectiveness at 
attenuating underwater noise. The POA will also conduct acoustic 
monitoring for vibratory pile driving to determine the actual distance 
to the 120 dB re 1[mu]Pa rms isopleth for behavioral harassment 
relative to background levels (estimated to be 125 dB re 1[mu]Pa in the 
project area).
    A typical daily sequence of operations for an acoustic monitoring 
day will include the following activities:
     Discussion of the day's pile-driving plans with the crew 
chief or appropriate contact and determination of setup locations for 
the fixed positions. Considerations include the piles to be driven and 
anticipated barge movements during the day.
     Calibration of hydrophones.
     Setup of the near (10-meter) system either on the barge or 
the existing dock.
     Deployment of an autonomous or cabled hydrophone at one of 
the distant locations.
     Recording pile driving operational conditions throughout 
the day.
     Upon conclusion of the day's pile driving, retrieve the 
remote systems, post-calibrate all the systems, and download all 
systems.
     A stationary hydrophone recording system will be suspended 
either from the pile driving barge or existing docks at approximately 
10 meters from the pile being driven, for each pile driven. These data 
will be monitored in real-time.
     Prior to monitoring, a standard depth sounder will record 
depth before pile driving commences. The sounder will be turned off 
prior to pile driving to avoid interference with acoustic monitoring. 
Once the monitoring has been completed, the water depth will be 
recorded.
     A second stationary hydrophone will be deployed across the 
Knik Arm near Port MacKenzie, approximately 2,800-3,200 meters from the 
pile, from either an anchored floating raft or an autonomous hydrophone 
recorder package (Figure 13-2 and Figure 13-3 in Application). At 3,000 
meters, the hydrophone will be located in the water approximately 
three-quarters of the way across Knik Arm. The autonomous hydrophone is 
a self-contained system that is anchored and suspended from a float. 
Data collected using this system will not be in real-time; the distant 
hydrophones will collect a continuous recording of the noise produced 
by the piles being driven.
    Vessel-based Hydrophones (One to Two Locations):
     An acoustic vessel with a single-channel hydrophone will 
be in the Knik Arm open water environment to monitor near-field and 
real-time isopleths for marine mammals (Figure 13-1, Figure 13-4 in 
Application).
     Continuous measurements will be made using a sound level 
meter.
     One or two acoustic vessels are proposed to deploy 
hydrophones that will be used to collect data to estimate the distance 
to far-field sound levels (i.e., the 120-125-dB zone for vibratory and 
160-dB zone for impact driving).
     During the vessel-based recordings, the engine and any 
depth finders must be turned off. The vessel must be silent and 
drifting during spot recordings.
     Either a weighted tape measure or an electronic depth 
finder will be used to determine the depth of the water before 
measurement and upon completion of measurements. A GPS unit or range 
finder will be used to determine the distance of the measurement site 
to the piles being driven.
     Prior to and during the pile-driving activity, 
environmental data will be gathered, such as water depth and tidal 
level, wave height, and other factors, that could contribute to 
influencing the underwater sound levels (e.g., aircraft, boats, etc.). 
Start and stop time of each pile-driving event and the time at which 
the bubble curtain is turned on and off will be logged.
     The construction contractor will provide relevant 
information, in writing, to the hydroacoustic monitoring contractor for 
inclusion in the final monitoring report:

Data Collection

    MMOs will use approved data forms. Among other pieces of 
information, POA will record detailed information about any 
implementation of shutdowns, including the distance of animals to the 
pile and description of specific actions that ensued and resulting 
behavior of the animal, if any. In addition, POA will attempt to 
distinguish between the number of individual animals taken and the 
number of incidents of take. At a minimum, the following information 
would be collected on the sighting forms:
     Date and time that monitored activity begins or ends;
     Construction activities occurring during each observation 
period;
     Weather parameters (e.g., percent cover, visibility);
     Water conditions (e.g., sea state, tide state);
     Species, numbers, and, if possible, sex and age class of 
marine mammals;
     Description of any observable marine mammal behavior 
patterns, including bearing and direction of travel and distance from 
pile driving activity;
     Distance from pile driving activities to marine mammals 
and distance from

[[Page 78190]]

the marine mammals to the observation point;
     Locations of all marine mammal observations; and
     Other human activity in the area.

Reporting Measures

    POA would provide NMFS with a draft monitoring report within 90 
days of the conclusion of the proposed construction work or 60 days 
prior to any subsequent authorization, whichever is sooner. A 
monitoring report is required before another authorization can be 
issued to POA. This report will detail the monitoring protocol, 
summarize the data recorded during monitoring, and estimate the number 
of marine mammals that may have been harassed. If no comments are 
received from NMFS within 30 days, the draft final report will 
constitute the final report. If comments are received, a final report 
must be submitted within 30 days after receipt of comments.
    In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner prohibited by the IHA 
(if issued), such as an injury, serious injury or mortality (e.g., 
ship-strike, gear interaction, and/or entanglement), POA would 
immediately cease the specified activities and report the incident to 
the Chief of the Permits and Conservation Division, Office of Protected 
Resources, NMFS, and the Alaska Regional Stranding Coordinators. The 
report would include the following information:
     Time, date, and location (latitude/longitude) of the 
incident;
     Name and type of vessel involved;
     Vessel's speed during and leading up to the incident;
     Description of the incident;
     Status of all sound source use in the 24 hours preceding 
the incident;
     Water depth;
     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 POA to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. POA would not be able to 
resume their activities until notified by NMFS via letter, email, or 
telephone.
    In the event that POA discovers an injured or dead marine mammal, 
and the lead MMO 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 as described in the next paragraph), 
POA would immediately report the incident to the Chief of the Permits 
and Conservation Division, Office of Protected Resources, NMFS, and the 
NMFS Alaska Stranding Hotline and/or by email to the Alaska Regional 
Stranding Coordinators. The report would include the same information 
identified in the paragraph above. Activities would be able to continue 
while NMFS reviews the circumstances of the incident. NMFS would work 
with POA to determine whether modifications in the activities are 
appropriate.
    In the event that POA discovers an injured or dead marine mammal, 
and the lead MMO 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), POA would report the incident to 
the Chief of the Permits and Conservation Division, Office of Protected 
Resources, NMFS, and the NMFS Alaska Stranding Hotline and/or by email 
to the Alaska Regional Stranding Coordinators, within 24 hours of the 
discovery. POA would provide photographs or video footage (if 
available) or other documentation of the stranded animal sighting to 
NMFS and the Marine Mammal Stranding Network.

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 pile driving and impact pile driving and are likely to 
involve temporary changes in behavior. Physical injury or lethal takes 
are not expected due to the expected source levels and sound source 
characteristics associated with the activity, and the proposed 
mitigation and monitoring measures are expected to further minimize the 
possibility of such take.
    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, where NMFS believes take is likely.
    Upland work can generate airborne sound and create visual 
disturbance that could potentially result in disturbance to marine 
mammals (specifically, pinnipeds) that are hauled out or at the water's 
surface with heads above the water. However, because there are no 
regular haul-outs in the vicinity of the site of the proposed project 
area, we believe that incidents of incidental take resulting from 
airborne sound or visual disturbance are unlikely.
    POA has requested authorization for the incidental taking of small 
numbers of Steller sea lion, harbor seal, harbor porpoise, killer whale 
and beluga whale near the project area that may result from vibratory 
and impact pile driving during activities associated with a Test Pile 
Program.
    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 
consider in combination with 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 generic 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. To date, no studies have 
been conducted that explicitly examine impacts to marine mammals from 
pile driving sounds or from which empirical sound thresholds have been 
established. These thresholds (Table 4) are used to estimate when 
harassment may occur (i.e., when an animal is exposed to levels equal 
to or exceeding the relevant criterion) in specific contexts; however, 
useful contextual information that may inform our assessment of effects 
is typically lacking and we consider these thresholds as step 
functions. NMFS is

[[Page 78191]]

working to revise these acoustic guidelines; for more information on 
that process, please visit www.nmfs.noaa.gov/pr/acoustics/guidelines.htm.

 Table 4--Underwater Injury and Disturbance Threshold Decibel Levels for
                             Marine Mammals
------------------------------------------------------------------------
          Criterion           Criterion definition       Threshold *
------------------------------------------------------------------------
Level A harassment..........  PTS (injury) **.....  190 dB RMS for
                                                     pinnipeds.
                                                    180 dB RMS for
                                                     cetaceans.
Level B harassment..........  Behavioral            160 dB RMS.
                               disruption for
                               impulse noise
                               (e.g., impact pile
                               driving).
Level B harassment..........  Behavioral            125 dB RMS ***.
                               disruption for non-
                               pulse noise (e.g.,
                               vibratory pile
                               driving, drilling).
------------------------------------------------------------------------
* All decibel levels referenced to 1 micropascal (re: 1 [mu]Pa). Note
  all thresholds are based off root mean square (RMS) levels
** PTS=Permanent Threshold Shift conservatively based on TTS (Temporary
  Threshold Shift)
*** Assuming ambient background noise of 125 dB RMS. Usually 120 dB RMS

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. 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 in the absence of reliable data and under conditions 
where water increases with depth 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.
    A review of underwater sound measurements for similar projects was 
undertaken to estimate the near-source sound levels for vibratory and 
impact pile driving at POA. Sounds from similar-sized steel shell piles 
have been measured in water for several projects. Measurements 
conducted for the US Navy Explosive Handling Wharf in the Hood Canal, 
in the Puget Sound at Naval Base Kitsap-Bangor, Washington, are most 
representative due to the similar pile size and depth of water at the 
site. Underwater sound levels at 10 m for 48-inch-diameter pile 
installation was measured at 164 dB RMS for vibratory driving and 192 
dB RMS for impact driving (Illingsworth & Rodkin 2012, 2013). This data 
was used to calculate distances to Level A and Level B thresholds.
    The formula for transmission loss is TL = X log10 (R/10), where R 
is the distance from the source assuming the near source levels are 
measured at 10 meters (33 feet) and X is the practical spreading loss 
value. This TL model, based on the default practical spreading loss 
assumption, was used to predict distances to isopleths for Level A 
injury and Level B harassment (Table 5). Pile-driving sound 
measurements recorded during the Test Pile Program will further refine 
the rate of sound propagation or TL and help inform the APMP marine 
mammal monitoring strategy.

   Table 5--Distances in Meters to NMFS' Level A (Injury) and Level B Harassment Thresholds (Isopleths) for a 48-Inch-Diameter Pile, Assuming a 125-dB
                                                                 Background Noise Level
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          Impact                                           Vibratory
                                                   -----------------------------------------------------------------------------------------------------
              Pile diameter  (inches)               Pinniped, level  Cetacean, level      Level B      Pinniped, level  Cetacean, level      Level B
                                                     A injury  190    A injury  180   harassment  160   A injury  190    A injury  180   harassment  125
                                                           dB               dB               dB               dB               dB               dB
--------------------------------------------------------------------------------------------------------------------------------------------------------
48, unattenuated..................................            14 m             63 m         1,359 km            <10 m            <10 m          3,981 m
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The distances to the Level B harassment and Level A injury 
isopleths were used to estimate the areas of the Level B harassment and 
Level A injury zones for an unattenuated a 48-inch pile. Note that 125 
dB was used as the Level B harassment zone isopleth since ambient noise 
is likely elevated in that area. Distances and areas were calculated 
for both vibratory and impact pile driving, and for cetaceans and 
pinnipeds. Geographic information system software was used to map the 
Level B harassment and Level A injury isopleths from each of the six 
indicator test pile locations. Land masses near the POA, including 
Cairn Point, the North Extension, and Port MacKenzie, act as barriers 
to underwater noise and prevent further spread of sound pressure waves. 
As such, the harassment zones for each threshold were truncated and 
modified with consideration of these impediments to sound transmission 
(See Figures 6-1--6-6 in the Application). The measured areas (Table 6) 
were then used in take calculations for beluga whales. Although sound 
attenuation methods will be used during pile installation, it

[[Page 78192]]

is unknown how effective they will be and for how many hours they will 
be utilized. Therefore, to estimate potential exposure of beluga 
whales, the areas of the harassment zones for impact and vibratory pile 
driving with no sound attenuation were used.

                                                            Table 6--Areas of the Level A Injury Zones and Level B Harassment Zones *
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Impact                                                                                              Vibratory
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                 Level B harassment
                                                                              ---------------------------------------------------------------------------------------  Pinniped,  Cetacean,    harassment
                                     Pinniped, level A     Cetacean, level A                                                                                            level A    level A  ---------------
                                          injury                injury         Indicator test piles         190 dB                180 dB                160 dB           injury     injury   190
                                                                                                                                                                                              dB
--------------------------------------------------------------------------------------------------------------------------------------------------------------------- -------------------------------------
Piles 3 and 4....................  <0.01 km\2\.........  <0.01 km\2\.........  2.24 km\2\..........  0 km\2\.............  0 km\2\.............  15.54 km\2\
Pile 1...........................  ....................  ....................  2.71 km\2\..........  ....................  ....................  19.54 km\2\
Pile 2...........................  ....................  ....................  2.76 km\2\..........  ....................  ....................  20.08 km\2\
Pile 5 and 6.....................  ....................  ....................  2.79 km\2\..........  ....................  ....................  20.90 km\2\
Pile 7...........................  ....................  ....................  2.80 km\2\..........  ....................  ....................  20.95 km\2\
Piles 8, 9, 10...................  ....................  ....................  3.03 km\2\..........  ....................  ....................  22.14 km\2\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
* Based on the distances to sound isopleths for a 48-inch-diameter pile, assuming a 125-dB background noise level.

    Incidental take is estimated for each species by estimating the 
likelihood of a marine mammal being present within a ZOI, described 
earlier in the mitigation section, during active pile driving. 
Monitoring data recorded for the MTRP were used to estimate daily 
sighting rates for harbor seals and harbor porpoises in the project 
area (See Table 4-1 and 4-2 in Application). Sighting rates of harbor 
seals and harbor porpoises were highly variable, and there was some 
indication that reported sighting rates may have increased during the 
years of MTRP monitoring. It is unknown whether any increase, if real, 
were due to local population increases or habituation to on-going 
construction activities. Shelden et al. (2014) reported evidence of 
increased abundance of harbor porpoise in upper Cook Inlet, which may 
have contributed to this pattern. As a conservative measure, the 
highest monthly individual sighting rate for any recorded year was used 
to quantify take of harbor seals and harbor porpoises for pile driving 
associated with the Test Pile Program.
    The pile driving take calculation for all harbor seal and harbor 
porpoise exposures is: Exposure estimate = (N) * # days of pile driving 
per site, where:
    N = highest daily abundance estimate for each species in project 
area
    Take for Steller sea lions was estimated based on three sightings 
of what was likely a single individual. Take for killer whales was 
estimated based on their known occasional presence in the project area, 
even though no killer whales were observed during past MTRP monitoring 
efforts.

Beluga Whale

    Aerial surveys for beluga whales in Cook Inlet were completed in 
June and July from 1993 through 2008 (Goetz et al. 2012). Data from 
these aerial surveys were used along with depth soundings, coastal 
substrate type, an environmental sensitivity index, an index of 
anthropogenic disturbance, and information on anadromous fish streams 
to develop a predictive beluga whale habitat model (Goetz et al. 2012). 
Three different beluga distribution maps were produced from the habitat 
model based on sightings of beluga whales during aerial surveys. First, 
the probability of beluga whale presence was mapped using a binomial 
(i.e., yes or no) distribution and the results ranged from 0.00 to 
0.01. Second, the expected group size was mapped. Group size followed a 
Poisson distribution, which ranged from 1 to 232 individuals in a 
group. Third, the product (i.e., multiplication) of these predictive 
models produced an expected density model, with beluga whale densities 
ranging from 0 to 1.12 beluga whales/km\2\. From this model Goetz et 
al. (2012) developed a raster GIS dataset which provides a predicted 
density of beluga whales throughout Cook Inlet at a scale of one square 
kilometer (See Figure 6-7 in the Application). Habitat maps for beluga 
whale presence, group size, and density (beluga whales/km\2\) were 
produced from these data and resulting model, including a raster 
Geographic Information System data set, which provides a predicted 
density of beluga whales throughout Cook Inlet at a 1-km\2\ scale grid.
    The numbers of beluga whales potentially exposed to noise levels 
above the Level B harassment thresholds for impact (160 dB) and 
vibratory (125 dB) pile driving were estimated using the following 
formula:
    Beluga Exposure Estimate = N * Area * # days of pile driving where:
    N = maximum predicted # of beluga whales/km\2\
    Area = Area of Isopleth (area in km\2\ within the 160-dB isopleth 
for impact pile driving, or area in km\2\ within the 125-dB isopleth 
for vibratory pile driving); (Table 6)
    The beluga whale exposure estimate was calculated for each of the 
six indicator test pile locations separately, because the area of each 
isopleth was different for each location. The predicted beluga whale 
density raster (developed by Goetz et al. 2012) was overlaid with the 
isopleth areas for each of the indicator test pile locations. The 
maximum predicted beluga whale density within each area of isopleth was 
then used to calculate the beluga whale exposure estimate for each of 
the indicator test pile locations. The maximum density values ranged 
from 0.031 to 0.063 beluga whale/km\2\.
    The area values from Table 6 were multiplied by these maximum 
predicted densities. The final step in the equation is to account for 
the number of days of exposure. As discussed in Section 1.2, the 
maximum number of days of impact pile driving, plus a 25 percent 
contingency, is 31 days. As such, the predicted exposure estimate for 
each of the 10 indicator test piles was multiplied by 3.1 to account 
for the number of days of exposure. The maximum number of days of 
vibratory pile driving (10), plus a 25 percent contingency, is 12.5 
days. As such, the predicted exposure estimate for each indicator test 
pile was multiplied by 1.25 to account for the number of days of 
exposure. The total estimated exposure of beluga whales to Level B 
harassment from impact pile driving (160 dB) is 3.884. The total 
estimated exposure of beluga whales to Level B harassment from 
vibratory pile driving (125 dB) is 15.361. The expected number of 
beluga whale exposures for

[[Page 78193]]

each indicator test pile and total exposure estimates is shown in Table 
7.

 Table 7--Maximum Predicted Beluga Whale Densities and Exposure Estimates Within Each of the Six Unique Isopleth
                                                      Areas
----------------------------------------------------------------------------------------------------------------
                                                                     Vibratory
                                                  Impact driving      driving                        Vibratory
                                                      (160 dB)        (125dB)     Impact driving      driving
               Indicator test pile                    maximum         maximum         exposure       exposure
                                                      density         density        estimate        estimate
                                                  (whales/km\2\)  (whales/km\2\)
----------------------------------------------------------------------------------------------------------------
3,4.............................................           0.031           0.056           0.428           2.191
1...............................................           0.042           0.063           0.350           1.541
2...............................................           0.038           0.062           0.329           1.550
5,6.............................................           0.062           0.062           1.066           3.225
7...............................................           0.062           0.062           0.536           1.617
8,9,19..........................................           0.042           0.063           1.175           5.238
                                                 ---------------------------------------------------------------
    Total Exposure Estimates....................  ..............  ..............           3.884          15.361
----------------------------------------------------------------------------------------------------------------

    Based on predicted beluga whale density in the vicinity of the POA, 
an estimated total of 19.245 beluga whales could be exposed to noise 
levels at the Level B harassment level during vibratory and impact pile 
driving (Table 7).
    Beluga whale distribution in Cook Inlet is much more clumped than 
is portrayed by the estimated density model (See Figure 6-7 in 
Application). Beluga whales are highly mobile animals that move based 
on tidal fluctuations, prey abundance, season, and other factors. 
Generally, beluga whales pass through the vicinity of the POA to reach 
high-quality feeding areas in upper Knik Arm or at the mouth of the 
Susitna River. Although beluga whales may occasionally linger in the 
vicinity of the POA, they typically transit through the area. It is 
important to note that the instantaneous probability of observing a 
beluga whale at any given time is extremely low (0.0 to 0.01) based on 
the Goetz et al. (2012) model; however, the probability of observing a 
beluga whale can change drastically and increase well above predicted 
values based on season, prey abundance, tide stage, and other 
variables. The Goetz et al. (2012) density model is the best available 
information for upper Cook Inlet and for the estimation of beluga whale 
density across large areas. However, in order to account for the 
clumped and highly variable distribution of beluga whales, we have 
accounted for large groups to improve our estimate of exposure.
    During previous POA monitoring, large groups of beluga whales were 
seen swimming through the POA vicinity. Based on reported takes in 
monitoring reports from 2008 through 2011, groups of beluga whales were 
occasionally taken by Level B harassment during previous POA activities 
(See Table 6-9 in Application).
    During past monitoring efforts, an occasional group of animals was 
observed, and on three occasions, groups of five beluga whales or more 
were observed (See Table 6-9 in Application). Therefore, the use of the 
beluga exposure estimate formula alone does not account for larger 
groups of beluga whales that could be taken, and does not work well for 
calculating relatively minor, short-term construction events involving 
small population densities or infrequent occurrences of marine mammals.
    The beluga density estimate used for estimating potential beluga 
exposures does not accurately reflect the reality that beluga whales 
can travel in large groups. As a contingency that a large group of 
beluga whales could occur in the project area, NMFS buffered the 
exposure estimate detailed in the preceding by adding the estimated 
size of a notional large group of beluga whales. Incorporation of large 
groups into the beluga whale exposure estimate is intended to reduce 
risk to the Test Pile Program of the unintentional take of a larger 
number of belugas than would be authorized by using the density method 
alone. A common convention in statistics and other fields is use of the 
95th percentile to evaluate risk. Use of the 95th percentile of group 
size to define a large group of beluga whales, which can be added to 
the estimate of exposure, calculated by the density method, provides a 
conservative value that reduces the risk to the POA of taking a large 
group of beluga whales and exceeding authorized take levels. A single 
large group has been added to the estimate of exposure for beluga 
whales based on the density method, in the anticipation that the entry 
of a large group of beluga whales into a Level B harassment zone would 
take place, at most, one time during the project. To determine the most 
appropriate size of a large group, two sets of data were examined: (1) 
Beluga whale sightings collected opportunistically by POA employees 
since 2008 (See Table 6-10 in Application), and (2) Alaska Pacific 
University (APU) scientific monitoring that occurred from 2007 through 
2011 (See Table 6-11, Figure 1-1 in Application). It is important to 
understand how data were collected for each data set to assess how the 
data can be used to determine the size of a large group.
    POA employees are encouraged to document opportunistic sightings of 
beluga whales in a logbook. This has resulted in a data set of beluga 
sightings that spans all months over many years, and includes estimates 
of group size. Observations were not conducted systematically or from 
the same location, and this data set is likely to be biased in that 
smaller groups or individual whales are less likely to be sighted than 
larger groups. However, the data set contains good information on 
relative frequency of sightings and maximum group sizes. The APU data 
were collected systematically by dedicated observers, and bias against 
small groups is likely less than for the POA opportunistic sightings. 
However, the APU data were collected over a more limited range of 
dates, and sampling effort was less in April and May, when the Test 
Pile Program is scheduled. Both data sets are useful for assessing 
beluga group size in the POA area.
    The APU scientific monitoring data set documents 390 beluga whale 
sightings. Group size exhibits a mode of 1 and a median of 2, 
indicating that over

[[Page 78194]]

half of the beluga groups observed over the 5-year span of the 
monitoring program were of individual beluga whales or groups of 2. As 
expected, the opportunistic sighting data from the POA do not reflect 
this preponderance of small groups. The POA opportunistic data do 
indicate, however, that large groups of belugas were regularly seen in 
the area over the past 7 years, and that group sizes ranged as high as 
100 whales. Of the 131 sightings documented in the POA opportunistic 
data set, 48 groups were of 15 or more beluga whales.
    The 95th percentile of group size for the APU scientific monitoring 
data is 11.1 beluga whales (rounded up to 12 beluga whales). This means 
that, of the 390 documented beluga whale groups in this data set, 95 
percent consisted of fewer than 11.1 whales; 5 percent of the groups 
consisted of more than 11.1 whales. Therefore, it is improbable that a 
group of more than 12 beluga whales would occur during the Test Pile 
Program. This number balances reduced risk to the POA with protection 
of beluga whales. POA opportunistic observations indicate that many 
groups of greater than 12 beluga whales commonly transit through the 
project area. APU scientific monitoring data indicate that 5 percent of 
their documented groups consisted of greater than 12 beluga whales. To 
reduce the chance of the POA reaching or exceeding authorized take, and 
to minimize harassment to beluga whales, in-water pile driving 
operations will be shut down if a group of 5 or more beluga whales is 
sighted approaching the Level B harassment 160 dB and 125 dB isopleths. 
Although POA would shut down for groups of 5 or more belugas, NMFS 
assumes here that a large group occurring in the far reaches of the ZOI 
may not be observed by the MMOs.
    The total number of proposed takes of Cook Inlet beluga whales is, 
therefore, 19.245 (density method) plus 12 (large group method) rounded 
up to a conservative 32 total incidents of take. No Level A harassment 
is expected or proposed.

Harbor Seal

    Airborne noise was not considered in this analysis since no known 
harbor seal haul-out or pupping sites occur in the vicinity of the POA. 
With the exception of newborn pups, all ages and sexes of harbor seals 
could occur in the project area for the duration of the Test Pile 
Program. However, harbor seals are not known to regularly reside in the 
POA area. For these reasons, any harassment to harbor seals during test 
pile driving will primarily involve a limited number of individuals 
that may potentially swim through the project area. Harbor seals that 
are disturbed by noise may change their behavior and be temporarily 
displaced from the project area for the short duration of test pile 
driving.
    The maximum number of harbor seals observed during POA construction 
monitoring conducted from 2005 through 2011 was 57 individuals, 
recorded over 104 days of monitoring, from June-November 2011. Based on 
these observations, sighting rates during the 2011 POA construction 
monitoring period were 0.55 harbor seal/day. Take by Level B harassment 
during 31 days of impact and vibratory pile driving for the Test Pile 
Program is anticipated to be less than 1 harbor seal per day. With in 
water pile driving occurring for only about 27 hours over those 31 
days, the potential for exposure within the 160-dB and 125-dB isopleths 
is anticipated to be low. Level B take is conservatively estimated at a 
total of 31 harbor seals (31 days x 1 harbor seal/day) for the duration 
of the Test Pile Program. Few harbor seals are expected to approach the 
project area, and this small number of takes is expected to have no 
more than a negligible effect on individual animals, and no effect on 
the population as a whole. Level B harassment has the most potential to 
occur during the mid-summer and fall when anadromous prey fish return 
to Knik Arm, in particular near Ship Creek south of the POA area. 
Because the unattenuated 190-dB isopleth is estimated to extend only 14 
meters from the source, no Level A harassment take is anticipated or 
proposed under this authorization.

Steller Sea Lion

    Steller sea lions are expected to be encountered in low numbers, if 
at all, within the project area. Based on the three sightings of what 
was likely a single individual in the project area in 2009, NMFS 
proposes an encounter rate of 1 individual every 5 pile driving days. 
The proposed Test Pile Program will drive piles for up to 31 days and, 
therefore, NMFS proposes the take of up to 6 individuals over the 
duration of test pile driving activities. Because the unattenuated 190-
dB isopleth is estimated to extend only 14 meters from the source, no 
Level A harassment take is anticipated or proposed.

Harbor Porpoises

    Aerial surveys designed specifically to estimate population size 
for the three management stocks of harbor porpoises in Alaska were 
conducted in 1997, 1998, and 1999 (Hobbs and Waite 2010). As part of 
the overall effort, Cook Inlet harbor porpoises were surveyed 9-15 June 
1998 by NMFS as part of their annual beluga whale survey effort (Hobbs 
and Waite 2010; Rugh et al. 2000). The survey yielded an average harbor 
porpoise density in Cook Inlet of 0.013 harbor porpoise/km\2\, with a 
coefficient of variation of 13.2 percent. Although the survey transited 
both upper and lower Cook Inlet, harbor porpoise sightings were limited 
to 8, all of which were south of Tuxedni Bay, in lower Cook Inlet; no 
harbor porpoises were sighted during this survey in upper Cook Inlet. 
Given the summer timing of this survey effort and lack of upper Cook 
Inlet sightings, NMFS determined that use of this density for 
estimating take of harbor porpoises in association with the Test Pile 
Program, which is planned for the fall season, will not be appropriate.
    Harbor porpoise sighting rates during the POA pre-construction 
monitoring period in 2007 were rare, and only four sightings were 
reported in 2005 (Table 4-2). Harbor porpoise sighting rates in the 
project area from 2008-2011 during pile driving and other port 
activities ranged from 0-0.09 harbor porpoise/day. We have rounded this 
up to 1 harbor porpoise per day. Take by Level B harassment during the 
Test Pile Program over 31 days of pile driving activity is estimated to 
be no more than 31 harbor porpoises (31 days x 1 harbor porpoise/day). 
Harbor porpoises sometimes travel in small groups, so as a contingency, 
an additional 6 harbor porpoise takes are estimated, for a total of 37 
Level B takes. With in-water pile driving occurring for only about 27 
hours over those 31 days, the potential for exposure within the 160-dB 
and 125-dB isopleths is anticipated to be low. Because the unattenuated 
190-dB isopleth is estimated to extend only 63 meters from the source, 
no Level A take is anticipated, nor requested under this authorization.

Killer Whales

    No killer whales were sighted during previous monitoring programs 
for the Knik Arm Crossing and POA construction projects, based on a 
review of monitoring reports. The infrequent sightings of killer whales 
that are reported in upper Cook Inlet tend to occur when their primary 
prey (anadromous fish for resident killer whales and beluga whales for 
transient killer whales) are also in the area (Shelden et al. 2003).
    With in-water pile driving occurring for only about 27 hours over 
31 days, the potential for exposure within the Level B harassment 
isopleths is anticipated to be extremely low. Level B

[[Page 78195]]

take is conservatively estimated at no more than 8 killer whales, or 
two small pods, for the duration of the Test Pile Program. Few killer 
whales are expected to approach the project area, and this small 
potential exposure is expected to have no more than a nominal effect on 
individual animals. Because the unattenuated 180-dB isopleth is 
estimated to extend only 63 meters from the source, no Level A 
harassment take is anticipated or proposed.

Analysis and Preliminary Determinations

Negligible Impact

    Negligible impact is ``an impact resulting from the specified 
activity that cannot be reasonably expected to, and is not reasonably 
likely to, adversely affect the species or stock through effects on 
annual rates of recruitment or survival'' (50 CFR 216.103). A 
negligible impact finding is based on the lack of likely adverse 
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of 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, 
NMFS must consider other factors, such as the likely nature of any 
responses (their intensity, duration, etc.), the context of any 
responses (critical reproductive time or location, migration, etc.), as 
well as the number and nature of estimated Level A harassment takes, 
the number of estimated mortalities, effects on habitat, and the status 
of the species.
    To avoid repetition, the discussion of our analyses applies to all 
the species listed in Table 2, given that the anticipated effects of 
this pile driving project on marine mammals are expected to be 
relatively similar in nature. Except for beluga whales, where we 
provide additional discussion, there is no information about the size, 
status, or structure of any species or stock that would lead to a 
different analysis for this activity, else species-specific factors 
would be identified and analyzed.
    Pile driving activities associated with the Test Pile Program, 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. Harassment takes could 
occur if individuals of these species are present in the ensonified 
zone when pile driving is happening.
    No injury, serious injury, or mortality is anticipated given the 
nature of the activity and measures designed to minimize the 
possibility of injury to marine mammals. The potential for these 
outcomes is minimized through the implementation of the following 
planned mitigation measures. POA will employ a ``soft start'' when 
initiating driving activities. Given sufficient ``notice'' through use 
of soft start, marine mammals are expected to move away from a pile 
driving source. The likelihood of marine mammal detection ability by 
trained observers is high under the environmental conditions described 
for waters around the project area. This further enables the 
implementation of shutdowns if animals come within 100 meters of 
operational activity to avoid injury, serious injury, or mortality. 
POA's proposed activities are localized and of relatively short 
duration. The total amount of time spent pile driving, including a 25% 
contingency, will be 27 hours over approximately 31 days.
    These localized and short-term noise exposures may cause brief 
startle reactions or short-term behavioral modification by the animals. 
These reactions and behavioral changes are expected to subside quickly 
when the exposures cease.
    The project also is not expected to have significant adverse 
effects on affected marine mammals' habitat, as analyzed in detail in 
the ``Anticipated Effects on Marine Mammal Habitat'' section. No 
important feeding and/or reproductive areas for marine mammals other 
than beluga whales are known to be near the proposed project area. 
Project-related 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.
    Beluga whales have been observed transiting past the POA project by 
both scientific and opportunistic surveys. During the spring and summer 
when the Test Pile Program is scheduled belugas are generally 
concentrated near warmer river mouths where prey availability is high 
and predator occurrence is low (Moore et al. 2000). Data on beluga 
whale sighting rates, grouping, behavior, and movement indicate that 
the POA is a relatively low-use area, occasionally visited by lone 
whales or small groups of whales. They are observed most often at low 
tide in the fall, peaking in late August to early September. Groups 
with calves have been observed to enter the POA area, but data do not 
suggest that the area is an important nursery area. Although POA 
scientific monitoring studies indicate that the area is not used 
frequently by many beluga whales, it is apparently used for foraging 
habitat by whales traveling between lower and upper Knik Arm, as 
individuals and groups of beluga whales have been observed passing 
through the area each year during monitoring efforts. Data collected 
annually during monitoring efforts demonstrated that few beluga whales 
were observed in July and early August; numbers of sightings increased 
in mid-August, with the highest numbers observed late August to mid-
September. In all years, beluga whales have been observed to enter the 
project footprint while construction activities were taking place, 
including pile driving and dredging. The most commonly observed 
behaviors were traveling, diving, and suspected feeding. No apparent 
behavioral changes or reactions to in-water construction activities 
were observed by either the construction or scientific observers 
(Cornick et al. 2011).
    Critical habitat for Beluga whales has been identified in the area. 
However, habitat in the immediate vicinity of the project has been 
excluded from critical habitat designation. Furthermore the project 
activities would not modify existing marine mammal habitat. NMFS 
concludes that both the short-term adverse effects and the long-term 
effects on Beluga whale prey quantity and quality will be 
insignificant. The sound from pile driving may interfere with whale 
passage between lower upper Knik Arm. However, POA is an industrialized 
area with significant noise from vessel traffic and beluga whales pass 
through the area unimpeded. Given the low use of the area, lack of 
observed behavioral changes associated with past construction 
operations, and nominal impact on critical habitat, NMFS believes that 
the proposed activity is not expected to impact rates of recruitment or 
survival for belugas whales and therefore will have a negligible impact 
on the species.
    Effects on individuals that are taken by Level B harassment, on the 
basis of reports in the literature as well as monitoring from other 
similar activities, will likely be limited to reactions such as 
increased swimming speeds, increased surfacing time, or decreased 
foraging (if such activity were occurring) (e.g., Thorson and Reyff, 
2006; Lerma, 2014). Most likely, individuals will

[[Page 78196]]

simply move away from the sound source and be temporarily displaced 
from the areas of pile driving, although even this reaction has been 
observed primarily only in association with impact pile driving. The 
pile removal activities analyzed here are similar to, or less impactful 
than, numerous construction activities conducted in other similar 
locations, which have taken place with no reported injuries or 
mortality to marine mammals, and no known long-term adverse 
consequences from behavioral harassment. Repeated exposures of 
individuals to levels of sound that may cause Level B harassment here 
are unlikely to result in hearing impairment or to significantly 
disrupt foraging behavior. Thus, even repeated Level B harassment of 
some small subset of the species is unlikely to result in any 
significant realized decrease in fitness for the affected individuals, 
and thus would not result in any adverse impact to the stock as a 
whole. Level B harassment will be reduced to the level of least 
practicable impact through use of mitigation measures described herein. 
Finally, if sound produced by project activities is sufficiently 
disturbing, animals are likely to simply avoid the project area while 
the activity is occurring.
    In summary, this negligible impact analysis is founded on the 
following factors for beluga whales: (1) The seasonal distribution and 
habitat use patterns of Cook Inlet beluga whales, which suggest that 
for much of the time only a small portion of the population would be in 
the vicinity of the Test Pile Program; (2) the proposed mitigation 
requirements, including shutdowns for groups of 5 or more belugas as 
well as for or calves approaching the Level B harassment area to avoid 
impacts to large numbers of belugas or to calves who may be more 
susceptible to acoustic impacts; (3) the proposed monitoring 
requirements and mitigation measures described earlier in this document 
for all marine mammal species that will further reduce the amount and 
intensity of takes; and (4) monitoring results from previous activities 
that indicated low numbers of beluga whale sightings within the Level B 
disturbance exclusion zone and low levels of Level B harassment takes 
of other marine mammals.
    For marine mammals other than beluga whales the negligible impact 
analysis is based on the following: (1) The possibility of injury, 
serious injury, or mortality may reasonably be considered discountable; 
(2) the anticipated incidents of Level B harassment consist of, at 
worst, temporary modifications in behavior; (3) the absence of any 
significant habitat within the project area, including rookeries, 
significant haul-outs, or known areas or features of special 
significance for foraging or reproduction; (4) the anticipated efficacy 
of the proposed mitigation measures in reducing the effects of the 
specified activity. 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 individuals. The specified activity is 
not expected to impact rates of recruitment or survival and will 
therefore have a negligible impact on those species.
    Therefore, based on the analysis contained herein of the likely 
effects of the specified activity on marine mammals and their habitat, 
and taking into consideration the implementation of the proposed 
monitoring and mitigation measures, NMFS preliminarily finds that the 
total marine mammal take from POA's Test Pile Program will have a 
negligible impact on the affected marine mammal species or stocks.

Small Numbers

    Table 8 indicates the numbers of animals that could be exposed to 
received noise levels that could cause Level B behavioral harassment 
from work associated with the proposed Test Pile Program. The analyses 
provided represents between <0.01% to 10.2% of the populations of these 
stocks that could be affected by Level B behavioral harassment. These 
are small numbers of marine mammals relative to the sizes of the 
affected species and population stocks under consideration.

   Table 8--Summary of the Estimated Numbers and Percentages of Marine Mammals Potentially Exposed to Level B
                                             Harassment Noise Levels
----------------------------------------------------------------------------------------------------------------
                                        Level B
             Species              harassment (160 or           Population             Percentage of population
                                        125 dB)
----------------------------------------------------------------------------------------------------------------
Harbor Seal.....................                  31  27,836......................  0.11.
Steller sea lion................                   6  49,497......................  <0.01.
Harbor porpoise.................                  37  31,046......................  0.12.
Killer whale....................                   8  2,347 Resident *............  0.34 Resident.
                                                      587 Transient...............  1.36 Transient.
Beluga whale....................                  32  312.........................  10.2.
                                 --------------------
      Total.....................                 114
----------------------------------------------------------------------------------------------------------------
* Percentage of population being requested for take is calculated out for the maximum of each killer stock.
  Eight takes are being requested total for both stocks.

    Based on the methods used to estimate take, and taking into 
consideration the implementation of the mitigation and monitoring 
measures, we preliminarily 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

    Under section 101(a)(5)(D), NMFS must find that the taking will not 
have an unmitigable adverse impact on the availability of the affected 
species for taking for subsistence uses. NMFS' implementing regulations 
define ``unmitigable adverse impact'' as an impact resulting from the 
specified activity:
    (1) That is likely to reduce the availability of the species to a 
level insufficient for a harvest to meet subsistence needs by:
    (i) Causing the marine mammals to abandon or avoid hunting areas;
    (ii) Directly displacing subsistence users; or
    (iii) Placing physical barriers between the marine mammals and the 
subsistence hunters; and

[[Page 78197]]

    (2) That cannot be sufficiently mitigated by other measures to 
increase the availability of marine mammals to allow subsistence needs 
to be met. (50 CFR 216.103).
    The primary concern is the disturbance of marine mammals through 
the introduction of anthropogenic sound into the marine environment 
during the proposed Test Pile Program. Marine mammals could be 
behaviorally harassed and either become more difficult to hunt or 
temporarily abandon traditional hunting grounds. However, the proposed 
Test Pile Program will not have any impacts to beluga harvests as none 
currently occur in Cook Inlet. Additionally, subsistence harvests of 
other marine mammal species in the proposed project area are limited.

Endangered Species Act (ESA)

    The Beluga whale is a marine mammal species listed as endangered 
under the ESA with confirmed or possible occurrence in the study area. 
NMFS' Permits and Conservation Division has initiated consultation with 
NMFS' Protected Resources Division under section 7 of the ESA on the 
issuance of an IHA to POA under section 101(a)(5)(D) of the MMPA for 
this activity. Consultation will be concluded prior to a determination 
on the issuance of an IHA.

National Environmental Policy Act (NEPA)

    NMFS is also preparing an Environmental Assessment (EA) in 
accordance with the National Environmental Policy Act (NEPA) and will 
consider comments submitted in response to this notice as part of that 
process. The EA will be posted at https://www.nmfs.noaa.gov/pr/permits/incidental/construction.htm once it is finalized.

Proposed Authorization

    As a result of these preliminary determinations, NMFS proposes to 
issue an IHA to POA for the POA Test Pile Program in Anchorage, Alaska, 
provided the previously mentioned mitigation, monitoring, and reporting 
requirements are incorporated. The proposed IHA language is provided 
next.
    1. This Incidental Harassment Authorization (IHA) is valid from 
April 1, 2016 through March 31, 2017.
    2. This Authorization is valid only for in-water construction work 
associated with the POA Test Pile Program in Anchorage, Alaska.
    3. General Conditions
    (a) A copy of this IHA must be in the possession of POA, its 
designees, and work crew personnel operating under the authority of 
this IHA.
    (b) The species authorized for taking are Steller sea lion 
(Eumatopius jubatus), harbor seal (Phoca vitulina), harbor porpoise 
(Phocoena phocoena), killer whale (Orcinus orca), and beluga whale 
(Delphinapterus Leucas)
    (c) The taking, by Level B harassment only, is limited to the 
species listed in condition 3(b).
    (d) The taking by injury (Level A harassment), serious injury, or 
death of any of the species listed in condition 3(b) of the 
Authorization or any taking of any other species of marine mammal is 
prohibited and may result in the modification, suspension, or 
revocation of this IHA.
    (e) POA shall conduct briefings between construction supervisors 
and crews, marine mammal monitoring team, and staff prior to the start 
of all in-water pile driving, and when new personnel join the work, in 
order to explain responsibilities, communication procedures, marine 
mammal monitoring protocol, and operational procedures.
    4. Mitigation Measures
    The holder of this Authorization is required to implement the 
following mitigation measures:
    (a) Time Restriction: For all in-water pile driving activities, POA 
shall operate only during daylight hours.
    (b) Pile Driving Weather Delays: Pile driving shall only take place 
when the 100 m shutdown zone cannot be can be adequately monitored.
    (c) Establishment of Level A and B Harassment (ZOI)
    (i) For all pile driving, POA shall implement a minimum shutdown 
zone of 100 m radius around the pile. If a marine mammal comes within 
or approaches the shutdown zone, such operations will cease. See Table 
5 for minimum radial distances required for Level A and Level B 
disturbance zones.
    (d) Shutdown for Large Groups of Beluga Whales.
    (i) In-water pile driving operations shall be shut down if a group 
of five or more beluga whales is sighted approaching the Level B 
harassment 160 dB and 125 dB isopleths. If the group is not re-sighted 
within 20 minutes, pile driving shall resume.
    (e) Shutdown for Beluga Whale Calves.
    (i) If a calf is sighted approaching a harassment zone, in-water 
pile driving shall cease and shall not be resumed until the calf is 
confirmed to be out of the harassment zone and on a path away from the 
pile driving. If a calf is not re-sighted within 20 minutes, pile 
driving shall resume.
    (f) Use of Soft-start
    (i) The project shall utilize soft start techniques for both impact 
and vibratory pile driving. POA shall initiate sound from vibratory 
hammers for fifteen seconds at reduced energy followed by a 1-minute 
waiting period, with the procedure repeated two additional times. For 
impact driving, POA shall conduct an initial set of three strikes from 
the impact hammer at 40 percent energy, followed by a 1-minute waiting 
period, then two subsequent three strike sets. Soft start shall be 
required at the beginning of each day's pile driving work and at any 
time following a cessation of pile driving of twenty minutes or longer 
(specific to either vibratory or impact driving).
    (ii) Whenever there has been downtime of 20 minutes or more without 
vibratory or impact driving, the contractor shall initiate the driving 
with soft-start procedures described above.
    (g) Standard mitigation measures
    (i) For in-water heavy machinery work other than pile driving 
(using, e.g., standard barges, tug boats), if a marine mammal comes 
within 10 m, operations shall cease and vessels shall reduce speed to 
the minimum level required to maintain steerage and safe working 
conditions.
    (h) Visual Marine Mammal Monitoring and Observation
    (i) Four MMOs shall work concurrently in rotating shifts to provide 
full coverage for marine mammal monitoring during in-water pile 
installation activities for the Test Pile Program. One MMO shall 
observe the Level A zone and two MMS shall scan the Level B zone. Four 
MMOs shall rotate through these three active positions every 30 
minutes. The fourth MMO shall record data.
    (ii) Before the Test Pile Program commences, MMOs and POA 
authorities shall meet to determine the most appropriate observation 
platform(s) for monitoring during pile driving.
    (iii) MMOs shall begin observing for marine mammals within the 
Level A and Level B harassment zones for 20 minutes before in-water 
pile driving begins. If a marine mammal(s) is present within the 100-
meter shutdown zone prior to pile driving or during the ``soft start'' 
the start of pile driving shall be delayed until the animal(s) leaves 
the 100-meter shutdown zone. Pile driving shall resume only after the 
MMOs have determined, through sighting or by waiting 20 minutes, that 
the animal(s) has moved outside the 100-meter shutdown zone.
    (iv) If a marine mammal is traveling along a trajectory that could 
take it into the Level B harassment zone, the MMO

[[Page 78198]]

shall record the marine mammal(s) as a ``take'' upon entering the Level 
B harassment zone. While the animal remains within the Level B 
harassment zone, that pile segment shall be completed without 
cessation, unless the animal approaches the 100-meter shutdown zone, at 
which point the MMO shall authorize the immediate shutdown of in-water 
pile driving before the marine mammal enters the 100- meter shutdown 
zone. Pile driving shall resume only once the animal has left the 100-
meter shutdown zone on its own or has not been resighted for a period 
of 20 minutes.
    (v) MMOs shall be placed on one of the vessels used for 
hydroacoustic monitoring, which will be stationed offshore.
    (vi) The individuals shall scan the waters within each monitoring 
zone activity using binoculars (25x or equivalent), hand held 
binoculars (7x) and visual observation.
    (vii) The waters shall be scanned 20 minutes prior to commencing 
pile driving at the beginning of each day, and prior to commencing pile 
driving after any stoppage of 20 minutes or greater. If marine mammals 
enter or are observed within the designated marine mammal buffer zone 
(the 100m radius) during or 20 minutes prior to impact pile driving, 
the monitors will notify the on-site construction manager to not begin 
until the animal has moved outside the designated radius.
    (viii) The waters shall continue to be scanned for at least 20 
minutes after pile driving has completed each day.
    5. Monitoring and Reporting
    The holder of this Authorization is required to submit a draft 
report on all monitoring conducted under the IHA 90 calendar days after 
the completion of the marine mammal monitoring or 60 days prior to the 
issuance of a subsequent authorization, whichever comes first. A final 
report shall be prepared and submitted within thirty days following 
resolution of comments on the draft report from NMFS. This report must 
contain the informational elements described in the Monitoring Plan, at 
minimum (see attached), and shall also include:
    (a) Acoustic Monitoring
    (i) POA conduct acoustic monitoring for representative scenarios of 
pile driving activity, as described in the Monitoring Plan.
    (b) Data Collection
    (i) For all marine mammal and acoustic monitoring, information 
shall be recorded as described in the Monitoring Plan.
    (c) Reporting Measures
    (i) In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner prohibited by the IHA, 
such as an injury (Level A harassment), serious injury or mortality 
(e.g., ship-strike, gear interaction, and/or entanglement), POA shall 
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 Regional Stranding 
Coordinators. The report would include the following information:
    1. Time, date, and location (latitude/longitude) of the incident;
    2. Name and type of vessel involved;
    3. Vessel's speed during and leading up to the incident;
    4. Description of the incident;
    5. Status of all sound source use in the 24 hours preceding the 
incident;
    6. Water depth;
    7. Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);
    8. Description of all marine mammal observations in the 24 hours 
preceding the incident;
    9. Species identification or description of the animal(s) involved;
    10. Fate of the animal(s); and
    11. Photographs or video footage of the animal(s) (if equipment is 
available).
    (ii) Activities would not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS shall work with POA to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. POA would not be able to 
resume their activities until notified by NMFS via letter, email, or 
telephone.
    (iii) In the event that POA discovers an injured or dead marine 
mammal, and the lead MMO 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 as described in the next paragraph), 
POA shall immediately report the incident to the Chief of the Permits 
and Conservation Division, Office of Protected Resources, NMFS, and the 
NMFS Alaska Stranding Hotline and/or by email to the Alaska Regional 
Stranding Coordinators. The report shall include the same information 
identified in the paragraph above. Activities would be able to continue 
while NMFS reviews the circumstances of the incident. NMFS would work 
with POA to determine whether modifications in the activities are 
appropriate.
    (iv) In the event that POA discovers an injured or dead marine 
mammal, and the lead MMO 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), POA shall report the incident to 
the Chief of the Permits and Conservation Division, Office of Protected 
Resources, NMFS, and the NMFS Alaska Stranding Hotline and/or by email 
to the Alaska Regional Stranding Coordinators, within 24 hours of the 
discovery. POA would provide photographs or video footage (if 
available) or other documentation of the stranded animal sighting to 
NMFS and the Marine Mammal Stranding Network.
    6. This Authorization may be modified, suspended or withdrawn if 
the holder fails to abide by the conditions prescribed herein, or if 
NMFS determines the authorized taking is having more than a negligible 
impact on the species or stock of affected marine mammals.

Request for Public Comments

    NMFS requests comment on our analysis, the draft authorization, and 
any other aspect of the Notice of Proposed IHA for POA's proposed Test 
Pile Program in Anchorage, Alaska. Please include with your comments 
any supporting data or literature citations to help inform our final 
decision on POA's request for an MMPA authorization.

    Dated: December 11, 2015.
Perry Gayaldo,
Deputy Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2015-31620 Filed 12-15-15; 8:45 am]
BILLING CODE 3510-22-P