[Federal Register Volume 80, Number 173 (Tuesday, September 8, 2015)]
[Notices]
[Pages 53777-53786]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-22069]


-----------------------------------------------------------------------

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XD978


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to the Rehabilitation of Jetty A at 
the Mouth of the Columbia River

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

ACTION: Notice; issuance of an incidental harassment authorization.

-----------------------------------------------------------------------

SUMMARY: In accordance with the regulations implementing the Marine 
Mammal Protection Act (MMPA) as amended, notification is hereby given 
that we have issued an incidental harassment authorization (IHA) to the 
U.S. Army Corp of Engineers (the Corps) to incidentally harass, by 
Level B harassment only, six species of marine mammals during 
activities related to the rehabilitation of Jetty A at the mouth of the 
Columbia River (MCR).

DATES: This authorization is effective from May 1, 2016 through April 
30, 2017.

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

SUPPLEMENTARY INFORMATION:

Availability

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

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct the Secretary of Commerce to allow, upon request, the 
incidental, but not intentional, taking of small numbers of marine 
mammals by U.S. citizens who engage in a specified activity (other than 
commercial fishing) within a specified geographical region if certain 
findings are made and either regulations are issued or, if the taking 
is limited to harassment, a notice of a proposed authorization is 
provided to the public for review.
    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.''
    Section 101(a)(5)(D) of the MMPA established an expedited process 
by which citizens of the U.S. can apply for an authorization to 
incidentally take small numbers of marine mammals by harassment. 
Section 101(a)(5)(D) establishes a 45-day time limit for NMFS' review 
of an application followed by a 30-day public notice and comment period 
on any proposed authorizations for the incidental harassment of marine 
mammals. Within 45 days of the close of the comment period, NMFS must 
either issue or deny the authorization. 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 13, 2015 NMFS received an application from the Corps 
for the taking of marine mammals incidental to the rehabilitation of 
Jetty A at the MCR. On June 9, 2015 NMFS received a revised 
application. NMFS determined that the application was adequate and 
complete on June 12, 2015. The Corps proposes to conduct in-water work 
that may incidentally harass marine mammals (i.e., pile driving and 
removal). The use of vibratory 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 killer 
whale (Orcinus orca), Steller sea lion (Eumatopius jubatus), gray whale 
(Eschrichtius robustus), harbor porpoise (Phocoena phocoena), 
California sea lion (Zalophus californianus), and harbor seal (Phoca 
vitulina richardii).

Description of the Specified Activity

Overview

    The Corps is seeking an IHA for the first year of pile installation 
and, possibly, removal work at Jetty A related to construction and 
maintenance of a barge offloading facility. The barge facility will be 
used for activities associated with the rehabilitation of Jetty A. The 
Corps is seeking this authorization by the end of August 2015 for 
contract bid scheduling reasons.

Dates and Duration

    Work on the first year of pile installation may begin as early as 
May 2016 and would extend through September 2017. Because the work may 
extend to two seasons the Corps has requested a Letter of Authorization 
(LOA) that would come into effect immediately after the IHA expires for 
the second year of pile maintenance and removal at Jetty A. The LOA 
would also

[[Page 53778]]

cover rehabilitation work planned for the North and South Jetties.

Specific Geographic Region

    This activity will take place at Jetty A at the MCR jetty system in 
Pacific County, Washington.

Detailed Description of Activities

    We provided a description of the proposed action in our Federal 
Register notice announcing the proposed authorization (80 FR 43739; 
July 23, 2015). Please refer to that document; we provide only summary 
information here.
    The scheduled rehabilitation of Jetty A would occur as part of the 
Corps' Major Rehabilitation program for the MCR jetty system. During 
the first year of the project, operators would install and potentially 
remove up to 24 24-in steel piles and 93 sections of Z or H piles using 
a vibratory hammer. USACE expects those activities to take 17 days and 
would limit them to daylight hours only.

Comments and Responses

    A notice of NMFS' proposal to issue an IHA was published in the 
Federal Register on July 23, 2015 (80 FR 43739). During the 30-day 
public comment period, the Marine Mammal Commission submitted a letter. 
The letter is available on the Internet at www.nmfs.noaa.gov/pr/permits/incidental/construction.htm. All comments specific to the 
Corps' application that address the statutory and regulatory 
requirements or findings NMFS must make to issue an IHA are addressed 
in this section of the Federal Register notice.
    Comment 1: The Commission recommends that a hydroacoustic 
monitoring plan be incorporated in subsequent years of activity under 
requested regulations, if and when issued. The Commission believes such 
a plan is prudent due to the types and sizes of piles to be installed 
and removed, the substrate of the environment, and the ambient sound 
and sound propagation loss associated with a river mouth opening into 
the open ocean.
    Response 1: NMFS agrees that a hydroacoustic monitoring plan would 
be valuable for defining potential injury and harassment zones during 
future years of the jetty rehabilitation project. There is very limited 
hydroacoustic data pertaining to the MCR. NMFS will work with the 
applicant to devise a monitoring plan during the next application 
cycle.

Description of Marine Mammals in the Area of the Specified Activity

    There are six marine mammal species known to occur in the vicinity 
of the MCR which may be subjected to Level B harassment. These are the 
killer whale, Steller sea lion, gray whale, harbor porpoise, California 
sea lion, and harbor seal.
    We have reviewed the Corps' detailed species descriptions, 
including life history information, for accuracy and completeness and 
refer the reader to Section 3 of the Corps' application as well as the 
proposed incidental harassment authorization published in the Federal 
Register (80 FR 43739) instead of reprinting the information here. 
Please also refer to NMFS' Web site (www.nmfs.noaa.gov/pr/species/mammals) for generalized species accounts which provide information 
regarding the biology and behavior of the marine resources that occur 
in the vicinity of the MCR. We provided additional information for the 
potentially affected stocks, including details of stock-wide status, 
trends, and threats, in our Federal Register notice of proposed 
authorization (80 FR 43739).
    Table 1 lists marine mammal stocks that could occur in the vicinity 
of the Jetty A project that may be subject to Level B harassment and 
summarizes key information regarding stock status and abundance. 
Taxonomically, we follow Committee on Taxonomy (2014). Please see NMFS' 
Stock Assessment Reports (SAR), available at www.nmfs.noaa.gov/pr/sars, 
for more detailed accounts of these stocks' status and abundance.

  Table 1--List of Marine Mammal Species Under NMFS Jurisdiction That Occur in the Vicinity of the MCR Project
                                                     Area *
----------------------------------------------------------------------------------------------------------------
                                 Stock(s) abundance                                      Frequency of occurrence
           Species                  estimate \1\         ESA status     MMPA * status              \3\
----------------------------------------------------------------------------------------------------------------
Killer Whale (Orcinus orca),   85...................  Endangered.....  Depleted and     Infrequent/Rare.
 Eastern N. Pacific, Southern                                           Strategic.
 Resident Stock.
Killer Whale (Orcinus orca),   243..................  ...............  Non-depleted...  Rare.
 Eastern N. Pacific, West
 Coast Transient Stock.
Gray Whale (Eschrichtius       18,017 (173).........  Delisted/        Non-depleted...  Rare.
 robustus), Eastern North                              Recovered
 Pacific Stock, (Pacific                               (1994).
 Coast Feed Group).
Harbor Porpoise (Phocoena      21,487...............  ...............  Non-depleted...  Likely.
 phocoena), Northern Oregon/
 Washington Coast Stock.
Steller Sea Lion (Eumetopias   63,160-78,198........  Delisted/        Depleted and     Likely.
 jubatus), Eastern U.S. Stock/                         Recovered        Strategic \2\.
 DPS**.                                                (2013).
California Sea Lion (Zalophus  296,750..............  ...............  Non-depleted...  Likely.
 californianus), U.S. Stock.
Harbor Seal (Phoca vitulina    24,732 \4\...........  ...............  Non-depleted...  Seasonal.
 richardii), Oregon and
 Washington Stock.
----------------------------------------------------------------------------------------------------------------
\1\ NOAA/NMFS 2014 marine mammal stock assessment reports at http://www.nmfs.noaa.gov/pr/sars/species.htm.
\2\ May be updated based on the recent delisting status.
\3\ Frequency defined here in the range of:
 Rare--Few confirmed sightings, or the distribution of the species is near enough to the area that the
  species could occur there.
 Infrequent--Confirmed, but irregular sightings.
 Likely--Confirmed and regular sightings of the species in the area year-round.
 Seasonal--Confirmed and regular sightings of the species in the area on a seasonal basis.
\4\ Data is 8 years old. No current abundance estimates exist.
* MMPA = Marine Mammal Protection Act.
** DPS = Distinct population segment.


[[Page 53779]]

Potential Effects of the Specified Activity on Marine Mammals

    The Federal Register notice of proposed authorization (80 FR 
43739), incorporated here by reference, provides a general background 
on sound relevant to the specified activity as well as a detailed 
description of marine mammal hearing and of the potential effects of 
these construction activities on marine mammals.

Anticipated Effects on Habitat

    We described potential impacts to marine mammal habitat in detail 
in our Federal Register notice of proposed authorization. In summary, 
the project activities would not modify existing marine mammal habitat. 
The activities may cause some fish to leave the area of disturbance, 
thus temporarily impacting marine mammals' foraging opportunities in a 
limited portion of the foraging range. 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 for individual 
marine mammals or their populations

Mitigation

    In order to issue an IHA under section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to such 
activity, ``and other means of effecting the least practicable impact 
on such species or stock and its habitat, paying particular attention 
to rookeries, mating grounds, and areas of similar significance, and on 
the availability of such species or stock for taking'' for certain 
subsistence uses.
    Measurements from similar pile driving events were coupled with 
practical spreading loss to estimate zones of influence (ZOI; see 
``Estimated Take by Incidental Harassment''). ZOIs are often used to 
establish a mitigation zone around each pile (when deemed practicable) 
to prevent Level A harassment to marine mammals, and also provide 
estimates of the areas within which Level B harassment might occur. 
ZOIs may vary between different diameter piles and types of 
installation methods. The Corps will employ the following mitigation 
measures:
    (a) Conduct briefings between construction supervisors and crews, 
marine mammal monitoring team, and the Corps' 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).

Monitoring and Shutdown for Pile Driving

    The following measures apply to the Corps' mitigation through 
shutdown and disturbance zones:
    Shutdown Zone--For all pile driving activities, the Corps will 
establish a shutdown zone. Shutdown zones are intended to contain the 
area in which SPLs equal or exceed the 180/190 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. The estimated shutdown zone for 
Level A injury to cetaceans would be 1 meter. The Corps, however, would 
implement a minimum shutdown zone of 10 m radius for all marine mammals 
around all vibratory pile driving and removal activities. These 
precautionary measures are intended to further reduce the unlikely 
possibility of injury from direct physical interaction with 
construction operations.
    Disturbance Zone--Disturbance zones are the areas in which sound 
pressure levels (SPLs) equal or exceed 120 dB rms (for continuous 
sound) for pile driving installation and removal. 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. Nominal radial distances for disturbance zones are 
shown in Table 2. The shutdown zone for Level B injury wound extend 
7,356 meters from the sound source. 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 ``Monitoring and 
Reporting.''

 Table 2--Calculated Area Encompassed Within Zone of Influence at MCR Jetties for Underwater Marine Mammal Sound
                                              Thresholds at Jetty A
----------------------------------------------------------------------------------------------------------------
                                  Underwater                                       Area excluding land & jetty
            Jetty                 threshold            Distance--m (mi)               masses--km\2\ (mi\2\)
----------------------------------------------------------------------------------------------------------------
Jetty A: ~ Station 78+50,      Vibratory        0.............................  0
 River Side.                    driving,
                                pinniped
                                injury (190
                                dB).
                               Vibratory        1 (3.3).......................  <0.000003 (0.000001)
                                driving,
                                cetacean
                                injury (180
                                dB).
                               Vibratory        7,356 (4.6 miles).............  23.63 (9.12)
                                driving,
                                disturbance
                                (120 dB).
----------------------------------------------------------------------------------------------------------------

    Time Restrictions--Work would occur only during daylight hours, 
when visual monitoring of marine mammals can be conducted. In order 
minimize impact to Southern resident killer whales, in-water work will 
not be conducted during their primary feeding season extending from 
October 1 until on or after May 1. Installation could occur from May 1 
through September 30 each year.
    In order to document observed incidents of harassment, observers 
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 estimated ZOIs for relevant activities (i.e., pile 
installation and removal). This information may then be used to 
extrapolate observed

[[Page 53780]]

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 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. The project will utilize soft start techniques for all 
vibratory pile driving. We require the Corps to initiate sound from 
vibratory hammers for fifteen seconds at reduced energy followed by a 
thirty-second waiting period, with the procedure repeated two 
additional times. 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.

Monitoring

    Monitoring Protocols--Monitoring would be conducted before, during, 
and after pile driving. In addition, observers shall record all 
incidents of marine mammal occurrence, regardless of distance from 
activity, and shall document any behavioral reactions in concert with 
distance from piles being driven. Observations made outside the 
shutdown zone will not result in shutdown and that pile segment would 
be completed without cessation, unless the animal approaches or enters 
the shutdown zone, at which point all pile driving activities would be 
halted. Monitoring will take place from thirty minutes prior to 
initiation through thirty minutes post-completion of pile driving 
activities. Pile driving activities include the time to remove a single 
pile or series of piles, as long as the time elapsed between uses of 
the pile driving equipment is no more than thirty minutes.
    The following additional measures apply to visual monitoring:
    (1) Monitoring will be conducted by qualified observers, who will 
be placed at the best vantage point(s) practicable to monitor for 
marine mammals and implement shutdown/delay procedures when applicable 
by calling for the shutdown to the hammer operator. One observer will 
be placed on or near the drilling rig near Jetty A while a second 
observer will be stationed on the opposite side of the observable zone 
of influence on Clatsop Spit. Qualified observers are trained 
biologists, with the following minimum qualifications:
    (a) Visual acuity in both eyes (correction is permissible) 
sufficient for discernment of moving targets at the water's surface 
with ability to estimate target size and distance; use of binoculars 
may be necessary to correctly identify the target;
    (b) Advanced education in biological science or related field 
(undergraduate degree or higher required);
    (c) Experience and ability to conduct field observations and 
collect data according to assigned protocols (this may include academic 
experience);
    (d) Experience or training in the field identification of marine 
mammals, including the identification of behaviors;
    (e) Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations;
    (f) Writing skills sufficient to prepare a report of observations 
including but not limited to the number and species of marine mammals 
observed; dates and times when in-water construction activities were 
conducted; dates and times when in-water construction activities were 
suspended to avoid potential incidental injury from construction sound 
of marine mammals observed within a defined shutdown zone; and marine 
mammal behavior; and
    (g) Ability to communicate orally, by radio or in person, with 
project personnel to provide real-time information on marine mammals 
observed in the area as necessary.
    (2) Prior to the start of pile driving activity, the shutdown zone 
will be monitored for 30 minutes to ensure that it is clear of marine 
mammals. Pile driving will only commence once observers have declared 
the shutdown zone clear of marine mammals; animals will be allowed to 
remain in the shutdown zone (i.e., must leave of their own volition) 
and their behavior will be monitored and documented. The shutdown zone 
may only be declared clear, and pile driving started, when the entire 
shutdown zone is visible (i.e., when not obscured by dark, rain, fog, 
etc.).
    If waters exceed a sea-state which restricts the observers' ability 
to make observations within the marine mammal shutdown zone (e.g. 
excessive wind or fog), pile installation will cease. Pile driving will 
not be initiated until the entire shutdown zone is visible.
    The waters will be scanned 30 minutes prior to commencing pile 
driving at the beginning of each day, and prior to commencing pile 
driving after any stoppage of 30 minutes or greater. If marine mammals 
enter or are observed within the designated marine mammal shutdown zone 
during or 30 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.
    If any marine mammal species are encountered during activities that 
are not listed in Table 1 for authorized taking and are likely to be 
exposed to sound pressure levels (SPLs) greater than or equal to 120 dB 
re 1mPa (rms), then the Holder of this Authorization must stop pile 
driving activities and report observations to NMFS' Office of Protected 
Resources at (301) 847-8401.
    If a marine mammal approaches or enters the shutdown zone during 
the course of vibratory pile driving operations, activity will be 
halted and delayed until the animal has voluntarily left and been 
visually confirmed beyond the shutdown zone. If a marine mammal is seen 
above water and then dives below, the contractor would wait 15 minutes 
for pinnipeds and 30 minutes for cetaceans. If no marine mammals are 
seen by the observer in that time it will be assumed that the animal 
has moved beyond the exclusion zone.
    Monitoring will be conducted throughout the time required to drive 
a pile.
    (3) Marine mammal presence within the Level B harassment zone will 
be monitored, but vibratory driving will not be stopped if marine 
mammals are found to be present. Any marine mammal documented within 
the Level B harassment zone during vibratory driving would constitute a 
Level B take (harassment), and will be recorded and reported as such.

Mitigation Conclusions

    We have carefully evaluated the Corps' proposed mitigation measures 
and considered their effectiveness in past implementation to determine 
whether they are likely to effect the least practicable impact on the 
affected marine mammal species and stocks and their habitat. Our 
evaluation of potential measures included consideration of the 
following factors in relation to one another: (1) The manner in which, 
and the degree to which, the successful implementation of the measure 
is expected to minimize adverse impacts to marine mammals, (2) the 
proven or likely efficacy of the specific measure to minimize adverse 
impacts as planned; and (3) the practicability of the measure for 
applicant implementation.
    Any mitigation measure(s) we prescribe should be able to 
accomplish, have a reasonable likelihood of accomplishing (based on 
current

[[Page 53781]]

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 number (total number or number at 
biologically important time or location) of individual marine mammals 
exposed to stimuli expected to result in incidental take (this goal may 
contribute to 1, above, or to reducing takes by behavioral harassment 
only).
    (3) A reduction in the number (total number or number at 
biologically important time or location) of times any individual marine 
mammal would be exposed to stimuli expected to result in incidental 
take (this goal may contribute to 1, above, or to reducing takes by 
behavioral harassment only).
    (4) A reduction in the intensity of exposure to stimuli expected to 
result in incidental take (this goal may contribute to 1, above, or to 
reducing the severity of behavioral harassment only).
    (5) Avoidance or minimization of adverse effects to marine mammal 
habitat, paying particular attention to the prey base, blockage or 
limitation of passage to or from biologically important areas, 
permanent destruction of habitat, or temporary 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 Corps' proposed measures, including 
information from monitoring of implementation of mitigation measures 
very similar to those described here under previous IHAs from other 
marine construction projects, we have determined that the proposed 
mitigation measures provide the means of effecting the least 
practicable impact on marine mammal species or stocks and their 
habitat, paying particular attention to rookeries, mating grounds, and 
areas of similar significance.

Monitoring and Reporting

    In order to issue an IHA for an activity, section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth ``requirements pertaining to 
the monitoring and reporting of such taking''. The MMPA implementing 
regulations at 50 CFR 216.104 (a)(13) indicate that requests for 
incidental take authorizations must include the suggested means of 
accomplishing the necessary monitoring and reporting that will result 
in increased knowledge of the species and of the level of taking or 
impacts on populations of marine mammals that are expected to be 
present in the proposed action area.
    Any monitoring requirement we prescribe should improve our 
understanding of one or more of the following:
    (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.
    The Corps consulted with NMFS to create a marine mammal monitoring 
plan as part of the IHA application for this project.

Visual Marine Mammal Observations

     Two individuals meeting the minimum qualifications 
previously identified will monitor the marine mammal buffer area and 
Level B harassment zones during vibratory pile. Monitors will be 
stationed on the drilling rig or Jetty A as well as on Clatsop Spit.
     During vibratory pile driving, the area within 10 meters 
of pile driving activity will be monitored and maintained as a marine 
mammal buffer area in which pile installation will not commence or will 
be suspended temporarily if any marine mammals are observed within or 
approaching the area of potential disturbance. The Level B harassment 
area will be monitored by 2 observers at locations listed above. The 
monitoring staff will record any presence of marine mammals by species, 
will document any behavioral responses noted, and record Level B takes 
when sightings overlap with pile installation activities.
     The individuals will scan the waters within each 
monitoring zone activity using binoculars (Vector 10X42 or equivalent), 
spotting scopes (Swarovski 20-60 zoom or equivalent), and visual 
observation.
     The area within which the Level B harassment thresholds 
could be exceeded during vibratory pile driving will be monitored for 
the presence of marine mammals. Marine mammal presence within these 
zones, if any, will be monitored but pile driving activity will not be 
stopped if marine mammals were found to be present. Any marine mammal 
documented within the Level B harassment zone will constitute a Level B 
take, and will be recorded and used to document the number of take 
incidents.
     If waters exceed a sea-state which restricts the 
observers' ability to make observations within the marine mammal buffer 
zone (e.g. excessive wind or fog), pile installation will cease until 
conditions allow the resumption of monitoring.
     The waters will be scanned for 30 minutes before, during, 
and 30 minutes after any and all pile driving and removal activities.
     If marine mammals enter or are observed within the 
designated marine mammal buffer zone (10 m) during or 30 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.
     If a marine mammal approaches the shutdown zone prior to 
initiation of pile driving, the Corps cannot commence activities until 
the marine mammal (a) is observed to have left the Level A harassment 
zone or (b) has not been seen or otherwise detected within the Level A 
harassment zone for 30 minutes.
     The waters will continue to be scanned for at least 30 
minutes after pile driving has completed each day, and

[[Page 53782]]

after each stoppage of 30 minutes or greater.

Data Collection

    We require that observers use approved data forms. Among other 
pieces of information, the Corps 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, the Corps will attempt to 
distinguish between the number of individual animals taken and the 
number of incidents of take. We require that, at a minimum, the 
following information 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 the marine mammals to the observation point;
     Locations of all marine mammal observations; and
     Other human activity in the area.

Reporting

    The Corps will notify NMFS prior to the initiation of the pile 
driving activities. The Corps will provide NMFS with a draft monitoring 
report within 90 days of the conclusion of the proposed construction 
work. 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.

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/removal and involving temporary changes in 
behavior. Injurious or lethal takes are not expected due to the 
expected source levels and sound source characteristics associated with 
the activity, and the planned 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 in every given situation 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, based on the available science.
    This practice potentially overestimates the numbers of marine 
mammals taken for stationary activities, as it is likely that some 
smaller number of individuals may accrue a number of incidences of 
harassment per individual than for each incidence to accrue to a new 
individual, especially if those individuals display some degree of 
residency or site fidelity and the impetus to use the site (e.g., 
because of foraging opportunities) is stronger than the deterrence 
presented by the harassing activity.
    The Corps requested authorization for the incidental taking of 
small numbers of killer whale, Gray whale, harbor porpoise, Steller sea 
lion, California sea lion, and harbor seal near the MCR project area 
that may result from vibratory pile driving and removal during 
construction activities associated with the rehabilitation of Jetty A 
at the MCR.
    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 provided detailed information on 
applicable sound thresholds for determining effects to marine mammals 
as well as 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, in our 
Federal Register notice of proposed authorization (80 FR 43739; July 
23, 2015).
    Table 2 above illustrated that during vibratory driving the120 dB 
Level B harassment threshold could be exceeded at 7,356 meters. Note 
that the actual area ensonified by pile driving activities is 
significantly constrained by local topography relative to the 
identified threshold radii.
    The method used for calculating potential exposures to vibratory 
pile driving noise for each threshold was estimated using local marine 
mammal data sets, the Biological Opinion, best professional judgment 
from state and federal agencies, and data from IHA estimates on similar 
projects with similar actions. All estimates are conservative and 
include the following assumptions:
     During construction, each species could be present in the 
project area each day. The potential for a take is based on a 24-hour 
period. The model assumes that there can be one potential take (Level B 
harassment exposure) per individual per 24-hours.
     All pilings installed at each site would have an 
underwater noise disturbance equal to the piling that causes the 
greatest noise disturbance (i.e., the piling furthest from shore) 
installed with the method that has the largest ZOI. The largest 
underwater disturbance ZOI would be produced by vibratory driving steel 
piles. The ZOIs for each threshold are not spherical and are truncated 
by land masses which would dissipate sound pressure waves.
     Exposures were based on an estimated 17 days of in-water 
work.

In absence of site specific underwater acoustic propagation modeling, 
the practical spreading loss model was used to determine the ZOI.
    Southern resident killer whales have been observed offshore near 
the study area and ZOI, but the Corps does not have fine-scale details 
on frequency of use. While killer whales do occur in the Columbia River 
plume, where fresh water from the river intermixes with salt water from 
the ocean, they are rarely seen in the interior of the Columbia River 
Jetty system. The ensonified area associated with the proposed action 
at Jetty A does not extend out into the open ocean where killer whales 
are likely to be found. Furthermore, the Corps has limited its pile 
installation window in order to avoid peak salmon runs and any overlap 
with the presence of Southern residents. To ensure no Level B 
acoustical harassment occurs, the Corps will restrict pile installation 
from October 1 until April 30 of each season. However, this restriction 
was

[[Page 53783]]

enacted primarily for construction work at the North and South jetties, 
where the ensonified zone will radiate out towards the open ocean. As 
such NMFS is not anticipating any acoustic exposure to Southern 
residents. Also note that in the 2011 Biological Opinion, NMFS issued a 
not likely to adversely affect determination. Therefore, NMFS has 
determined that authorization of take for Southern residents is not 
warranted.
    Western Transient killer whales may be traversing offshore over a 
greater duration of time than the feeding resident. They are rarely 
observed inside of the jetty system. The Southwest Fisheries Science 
Center (SWFSC) stratum model under the Marine Animal Monitor Model 
provides an estimated density of 0.00070853 animals per km\2\for summer 
killer whales for areas near MCR, which may provide a surrogate proxy 
value for assuming possible densities near the jetties (Barlow et al. 
2009, Halpin et al. 2009 at OBIS-SEAMAP). Given anecdotal evidence 
(Griffith 2015) and sightings recorded on the OBIS network from surveys 
done in 2005 (Halpin et al. 2009, OBIS-SEAMAP 2015), this density may 
be appropriate for the MCR vicinity.
    The following formula was used to calculate exposure using

Exposure Estimate = (0.000708DensityEstimate * 
23.63ZOI Jetty A * 17days) = 0.28 killer whale 
exposures

    Where:

NDensityEstimate = Represents estimated density of 
species within the 4.6-mile radius (23.63 km\2\) encompassing the 
ZOI at Jetty A; using the density model suggested by NOAA (2015), 
this equates to 0.000708 animals per km\2\(Barlow et al. 2009).
Days = Total days of pile installation or removal activity (~17 
days)

    Given the low density and rare occurrence of transient killer 
whales in the ZOI, exposure of feeding or transient killer whales to 
Level B acoustical harassment from pile driving is unlikely to occur. 
However, NMFS proposes to authorize take of small number due to the 
remote chance that transient orcas remain in the vicinity to feed on 
pinnipeds that frequent the haulouts at the South Jetty.
    NMFS believes that an authorized take of 8 transients is warranted 
because solitary killer whales are rarely observed, and transient 
whales travel in pods of 2-15 members. NMFS has assumed a pod size of 
8.
    Based on anecdotal information and sightings between 2006 and 2011 
(Halpin et al. 2009 at OBIS SEAMAP 2015), gray whales may be in the 
proximity of the proposed action area and exposed to underwater 
acoustic disturbances. However, no data exists that is specific to 
presence and numbers in the MCR vicinity and gray whale density 
estimates were not available on the SERDP or OBIS-SEAMAP web model 
sites. Anecdotal evidence also indicates gray whales have been seen at 
MCR, but are not a common visitor, as they mostly remain in the 
vicinity of the further offshore shelf-break (Griffith 2015). According 
to NOAA's Cetacean Mapping classification of the MCR vicinity 
pertaining to gray whale use, its Biologically Important Area 
categorization is indicated as a migration corridor (http://cetsound.noaa.gov/biologically-important-area-map). As primarily bottom 
feeders, gray whales are the most coastal of all great whales; they 
primarily feed in shallow continental shelf waters and live much of 
their lives within a few tens of kilometers of shore (Barlow et. al. 
2009 on OBIS--SEAMAP 2015).
    The Pacific Coast Feeding Group or northbound summer migrants would 
be the most likely gray whales to be in the vicinity of MCR. Since no 
information pertaining to gray whale densities could be identified, 
NMFS elected to apply proxy data for estimating densities. As a proxy, 
data pertinent to humpback whales (0.0039 animals per km\2\) was 
selected because both are baleen species found near the MCR vicinity 
for the same purposes (as a migration route or temporary feeding zone). 
However, the number of estimated exposures at Jetty A was increased to 
account for the fact that gray whales are more likely to be in the 
nearshore environment than humpback whales. This increase was proposed 
strictly as a conservative assumption to acknowledge the distinct 
preference gray whales may have over humpbacks for nearshore feeding.
    The following formula was used to calculate exposure:

Exposure Estimate = (0.0039DensityEstimate * 
23.63ZOI Jetty A * 17days) + 1 = 1.56 gray whale 
exposures

    Migrating gray whales often travel in groups of 2, although larger 
pods do occur. For gray whales, NMFS believes 4 Level B authorized 
takes is reasonable.
    Harbor porpoises are known to occupy shallow, coastal waters and, 
therefore, are likely to be found in the vicinity of the MCR. They are 
known to occur within the proposed project area, however, density data 
for this region is unavailable (Griffith 2015).
    The SWFSC stratum model under the Marine Animal Monitor Model 
provides an estimated density per km\2\ of year-round porpoises for 
areas near northern California, which may provide a surrogate proxy 
value for assuming possible densities near the jetties. Though not in 
the project vicinity, the range of 3.642 animals/km\2\(Barlow et al. 
2009, Halpin et al. 2009) is a relatively high density compared to 
values moving even further south along the model boundaries, for which 
the northern-most extent ends in California. Given anecdotal evidence 
(Griffith 2015) and sightings recorded on the OBIS network from surveys 
done between 1989 and 2005, (Halpin et al. 2009, OBIS-SEAMAP 2015), 
this higher density may be appropriate for the MCR vicinity, or may be 
conservative.
    The formula previously described was used to arrive at a take 
estimate for harbor porpoise.

Exposure Estimate = (3.642DensityEstimate * 
23.63ZOI Jetty A * 17days) = 1,464.

    Based on the density model suggested by NOAA (2015), the Corps has 
provided a very conservative maximum estimate of 1,464 harbor porpoise 
disturbance exposures over the 17 days of operation. However, this 
number of potential exposures does not accurately reflect the actual 
number of animals that would potentially be taken for the MCR jetty 
project. Rather, it is more likely that the same pod may be exposed 
more than once during the 17-day operating window. The highest 
estimated number of animals exposed on any single day based on the 
modeled proxy density (Barlow et al. 2009 at SERDP) and the jetty with 
the greatest ZOI is 193 animals (from South Jetty Channel). While the 
number of pods in the vicinity of the MCR is unknown, the size of the 
pods is usually assumed to be significantly smaller than 193 animals. 
According to OBIS-SEAMAP (2015 and Halpin et al. 2009), the normal 
range of group size generally consists of less than five or six 
individuals, though aggregations into large, loose groups of 50 to 
several hundred animals could occur for feeding or migration. Because 
the ZOI only extends for a maximum of 7,256 meters (4.6 miles), it may 
also be assumed that due to competition and territorial circumstances 
only a limited number of pods would be feeding in the ZOI at any 
particular time. If the modeled density calculations are assumed, then 
this means anywhere from 32 small pods to 2 large, 100-animal pods 
might be feeding during every day of pile installation. Given these 
values seem an unrealistic representation of use and pod densities

[[Page 53784]]

within any one of the ZOIs, NMFS is proposing an alternative 
calculation.
    NMFS conservatively assumed that a single, large feeding pod of 50 
animals forms within the ZOI for Jetty A on each day of pile 
installation. Though this is likely much higher than actual use by 
multiple pods in the vicinity, it more realistically represents a 
worst-case scenario for the number of animals that could potentially be 
affected by the proposed work. This calculation also assumes that it is 
a new pod of individuals would be affected on each installation day, 
which is also unlikely given pod residency. Therefore, NMFS is 
permitting a Level B take for 850 animals.
    There are haulout sites on the South Jetty used by pinnipeds, 
especially Steller sea lions. It is likely that pinnipeds that use the 
haulout area in would be exposed to 120 dB threshold acoustic threshold 
during pile driving activities. The number of exposures would vary 
based on weather conditions, season, and daily fluctuations in 
abundance. Based on a survey by the Washington Department of Fish & 
Wildlife (WDFW) the number of affected Steller sea lions could be 
between 200-800 animals per month; California sea lion numbers could 
range from 1 to 500 per month and the number of harbor seals could be 
as low as 1 to as high as 57 per month. Exposure and take estimates 
below are based on past pinniped data from WDFW (2000-2014 data), which 
had a more robust monthly sampling frequency relative to Oregon 
Department of Fish &Wildlife (ODFW) counts. The exception to this was 
for harbor seal counts, for which ODFW (also 2000-2014 data) had more 
sampling data in certain months. Therefore, ODFW harbor seal data was 
used for the months of May and July. Exposure estimates are much higher 
than take estimates. This is because unlike the exposure estimate which 
assumes all new individuals, the take estimate request assumes that 
some of the same individuals will remain in the area and be exposed 
multiple times during the short 17-day installation period to complete 
and remove each offloading facility (for a total of about 68 days). 
NMFS examined the estimated monthly average number of animals from 
2000-2014 hauled on South Jetty during May and June, which are the most 
likely months for pile installation as is shown in Table 3. There are 
no anticipated airborne exposures since the main haul out sites are not 
in close proximity to Jetty A. Note that the formula used by NMFS is 
different than that employed by the Corps in their application as NMFS 
is only analyzing potential impacts associated with Jetty A. To 
reiterate, these exposure estimates assume a new individual is exposed 
every day throughout each acoustic disturbance, for the entire duration 
of the project.

Exposure EstimateStellar = (Nest(May+June/2) * 
17underwater/piles days) = 12,750 Steller sea lions
Exposure EstimateCalifornia = (Nest(May+June/2) * 
17underwater/piles days) = 2,788 CA sea lions
Exposure EstimateHarbor = (Nest(May+June/2) * 
17underwater/piles days)= 493 Harbor porpoises

Where:

Nest = Estimated daily average number of animals for May 
and June hauled out at South Jetty based on WDFW data.
Duration = total days of pile installation or removal activity for 
underwater thresholds (17);

                   Table 3--Authorized Takes of Pinnipeds During Pile Installation at Jetty A
----------------------------------------------------------------------------------------------------------------
                                                                   Steller  sea     California     Harbor  seal
                                                                       lion          sea lion    ---------------
                              Month                              --------------------------------
                                                                     Avg \1\ #       Avg \1\ #     Avg \1\ \2\ #
----------------------------------------------------------------------------------------------------------------
April...........................................................             587              99  ..............
May.............................................................             824             125               0
June............................................................             676             202              57
July............................................................             358               1              10
August..........................................................             324             115               1
September.......................................................             209             249  ..............
October.........................................................             384             508  ..............
Avg Daily Count (May+June/2) \3\................................             750             164              29
    Total Exposures over Duration \4\ (17 days).................          12,750           2,788             493
----------------------------------------------------------------------------------------------------------------
\1\ WDFW average daily count per month from 2000-2014.
\2\ ODFW average daily count per month for May and July 2000-2014 due to additional available sampling data.
\3\ Conservatively assumes each exposure is to new individual, all individuals are new arrivals each month, and
  no individual is exposed more than one time.
\4\ Assumed 17 pile installation/removal days.

Analyses and Determinations

Negligible Impact Analysis

    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 4 given that the anticipated effects of 
this pile driving project on marine mammals are expected to be 
relatively similar in nature. 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 rehabilitation of Jetty 
A at the mouth of the Columbia River, as outlined

[[Page 53785]]

previously, have the potential to disturb or displace marine mammals. 
Specifically, the planned activities may result in take, in the form of 
Level B harassment (behavioral disturbance) only, from underwater 
sounds generated from pile driving. Potential takes could occur if 
individuals of these species are present in the ensonified zone when 
pile driving 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 construction method and the 
implementation of the planned mitigation measures. Specifically, 
vibratory hammers will be the only method of installation utilized. No 
impact driving is planned. Vibratory driving does not have significant 
potential to cause injury to marine mammals due to the relatively low 
source levels produced (site-specific acoustic monitoring data show no 
source level measurements above 180 dB rms) and the lack of potentially 
injurious source characteristics. The likelihood that marine mammal 
detection ability by trained observers is high under the environmental 
conditions described for the rehabilitation of Jetty A at MCR further 
enables the implementation of shutdowns to avoid injury, serious 
injury, or mortality.
    The Corps' proposed activities are localized and of short duration. 
The entire project area is limited to the Jetty A area and its 
immediate surroundings. Actions covered under the Authorization would 
include installing a maximum of 24 piles for use as dolphins and a 
maximum of 93 sections of Z or H piles for retention of rock fill over 
17 days. The piles would be a maximum diameter of 24 inches and would 
only be installed by vibratory driving method. The possibility exists 
that smaller diameter piles may be used but for this analysis it is 
assumed that 24 inch piles will be driven.
    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. Moreover, the proposed mitigation and 
monitoring measures are expected to reduce potential exposures and 
behavioral modifications even further. Additionally, no important 
feeding and/or reproductive areas for marine mammals are known to be 
near the proposed action area. Therefore, the take resulting from the 
proposed project is not reasonably expected to and is not reasonably 
likely to adversely affect the marine mammal species or stocks through 
effects on annual rates of recruitment or survival.
    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. The 
project activities would not modify existing marine mammal habitat. The 
activities may cause some fish to leave the area of disturbance, thus 
temporarily impacting marine mammals' foraging opportunities in a 
limited portion of the foraging range; but, because of the short 
duration of the activities and the relatively small area of the habitat 
that may be affected, the impacts to marine mammal habitat are not 
expected to cause significant or long-term negative consequences.
    Effects on individuals that are taken by Level B harassment, on the 
basis of reports in the literature as well as monitoring from 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 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. In response to vibratory 
driving, pinnipeds (which may become somewhat habituated to human 
activity in industrial or urban waterways) have been observed to orient 
towards and sometimes move towards the sound. The pile driving 
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 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 overall stock 
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 and, 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: (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 and; (3) the presumed efficacy of 
the proposed mitigation measures in reducing the effects of the 
specified activity to the level of least practicable impact. In 
combination, we believe that these factors, as well as the available 
body of evidence from other similar activities, demonstrate that the 
potential effects of the specified activity will have only short-term 
effects on individuals. The specified activity is not expected to 
impact rates of recruitment or survival and will therefore not result 
in population-level impacts.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the proposed monitoring and 
mitigation measures, NMFS finds that the total marine mammal take from 
the Corps' rehabilitation of Jetty A at MCR will have a negligible 
impact on the affected marine mammal species or stocks.

            Table 4--Estimated Percentage of Species/Stocks That May Be Exposed to Level B Harassment
----------------------------------------------------------------------------------------------------------------
                                                                  Total proposed
                             Species                                authorized       Abundance     Percentage of
                                                                       takes                        total stock
----------------------------------------------------------------------------------------------------------------
Killer whale (Western transient stock)..........................               8             243             3.2
Gray whale (Eastern North Pacific Stock)........................               4          18,017           <0.01
Harbor porpoise.................................................             850          21,487             3.9

[[Page 53786]]

 
Steller sea lion................................................          12,750   63,160-78,198   20.2-16.3-1.0
California sea lion.............................................           2,788         296,750            0.01
Harbor seal.....................................................             493          24,732             2.0
----------------------------------------------------------------------------------------------------------------

Small Numbers Analysis

    Table 4 illustrates the number of animals that could be exposed to 
received noise levels that could cause Level B behavioral harassment 
for the proposed work associated with the rehabilitation of Jetty A at 
MCR. The analyses provided above represents between <0.01%--20.9% of 
the populations of these stocks that could be affected by Level B 
behavioral harassment. The numbers of animals authorized to be taken 
for all species would be considered small relative to the relevant 
stocks or populations even if each estimated taking occurred to a new 
individual--an extremely unlikely scenario. For pinnipeds occurring in 
the vicinity of Jetty A, there will almost certainly be overlap in 
individuals present day-to-day, and these takes are likely to occur 
only within some small portion of the overall regional stock.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the mitigation and monitoring 
measures, which are expected to reduce the number of marine mammals 
potentially affected by the proposed action, NMFS finds 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

    There are no subsistence uses of marine mammals in the proposed 
project area; and, thus, no subsistence uses impacted by this action.

Endangered Species Act (ESA)

    There are two marine mammal species that are listed as endangered 
under the ESA with confirmed or possible occurrence in the study area: 
humpback whale and Southern resident killer whale. For the purposes of 
this IHA, NMFS determined that take of Southern resident killer whales 
was highly unlikely given the rare occurrence of these animals in the 
project area. A similar conclusion was reached for humpback whales. On 
March 18, 2011, NMFS signed a Biological Opinion concluding that the 
proposed action is not likely to jeopardize the continued existence of 
humpback whales and may affect, but is not likely to adversely affect 
Southern resident killer whales.

National Environmental Policy Act (NEPA)

    The Corps issued the Final Environmental Assessment Columbia River 
at the Mouth, Oregon and Washington Rehabilitation of the Jetty System 
at the Mouth of the Columbia River and Finding of No Significant Impact 
in 2011. The environmental assessment (EA) and finding of no 
significant interest (FONSI) were revised in 2012 with a FONSI being 
signed on July 26, 2012. NMFS has adopted the findings of the 2012 
FONSI.

Authorization

    As a result of these determinations, we have issued an IHA to the 
Corps for conducting the described activities related to the 
rehabilitation of Jetty A at the MCR from May 1, 2016 through April 30, 
2017 provided the previously described mitigation, monitoring, and 
reporting requirements are incorporated.

    Dated: September 1, 2015.
Perry Gayaldo,
Deputy Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2015-22069 Filed 9-4-15; 8:45 am]
 BILLING CODE 3510-22-P