Marine Mammals; Incidental Take During Specified Activities; Proposed Incidental Harassment Authorization, 58796-58802 [2014-23233]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 79, Number 189 (Tuesday, September 30, 2014)]
[Notices]
[Pages 58796-58802]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-23233]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

[FWS-R8-ES-2014-N190; FXFR1337088SSO0]


Marine Mammals; Incidental Take During Specified Activities; 
Proposed Incidental Harassment Authorization

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of receipt of application and proposed incidental 
harassment authorization; request for comments.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), have 
received an application from the United States Coast Guard (USCG) for 
authorization to take small numbers of marine mammals by harassment 
incidental to the replacement of pier piles and the potable water line 
at USCG Station Monterey in Monterey County, California. In accordance 
with provisions of the Marine Mammal Protection Act of 1972 (MMPA), as 
amended, we request comments on our proposed authorization for the 
applicant to incidentally take, by harassment, small numbers of 
southern sea otters from November 1, 2014, to October 31, 2015. We 
anticipate no take by injury or death and include none in this proposed 
authorization, which would be for take by harassment only.

DATES: Comments and information must be received by October 30, 2014.

ADDRESSES: You may submit comments by any one of the following methods:
    1. U.S. mail or hand-delivery: Steve Henry, Field Supervisor, 
Ventura Fish and Wildlife Office, 2493 Portola Road, Suite B, Ventura, 
CA 93003.
    2. Fax: 805-644-3958, attention to Steve Henry, Field Supervisor.
    3. Electronic mail (email): R8SSO-
IHAComment@fws.gov. Please include your name and U.S. mail 
address in your message.
    Electronic copies of the incidental harassment authorization 
request, the Final Environmental Assessment (EA), and Marine Mammal 
Monitoring Plan may be obtained by writing to the address specified 
above, telephoning the contact listed in FOR FURTHER INFORMATION 
CONTACT, or visiting the Internet at https://www.fws.gov/ventura/endangered/species/info/sso.html. Documents cited in this notice may 
also be viewed, by appointment, during regular business hours, at the 
aforementioned U.S. mail address.

FOR FURTHER INFORMATION CONTACT: To request copies of the application, 
the list of references used in this notice, and other supporting 
materials, contact Lilian Carswell at the address in ADDRESSES, or by 
email at LilianCarswell@fws.gov.

SUPPLEMENTARY INFORMATION:

Background

    Sections 101(a)(5)(A) and (D) of the MMPA, as amended (16 U.S.C. 
1371 (a)(5)(A) and (D)), authorize the Secretary of the Interior 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, provided that we make certain findings and either 
issue regulations or, if the taking is limited to harassment, provide a 
notice of a proposed authorization to the public for review and 
comment.
    We may grant authorization to incidentally take marine mammals if 
we find that the taking will have a negligible impact on the species or 
stock(s) and will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for subsistence uses. As part 
of the authorization process, we prescribe permissible methods of 
taking and other means of effecting the least practicable impact on the 
species or stock and its habitat, and requirements pertaining to the 
monitoring and reporting of such takings.
    The term ``take,'' as defined by the MMPA, means to harass, hunt, 
capture, or kill, or to attempt to harass, hunt, capture, or kill, any 
marine mammal. Harassment, as defined by the MMPA, means ``any act of 
pursuit, torment, or annoyance which (i) has the potential to injure a 
marine mammal or marine mammal stock in the wild [the MMPA calls this 
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 [the MMPA calls 
this Level B harassment].''
    The terms ``negligible impact,'' ``small numbers,'' and 
``unmitigable adverse impact'' are defined in 50 CFR 18.27, the 
Service's regulations governing take of small numbers of marine mammals 
incidental to specified activities. ``Negligible impact'' is defined as 
``an impact resulting from the specified activity that cannot be 
reasonably expected to, and is not reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival.'' The term ``small numbers'' is also defined 
in the regulations, but we do not rely on that definition here, as it 
conflates the terms ``small numbers'' and ``negligible impact,'' which 
we recognize as two separate and distinct requirements. Instead, in our 
small numbers determination, we evaluate whether the number of marine 
mammals likely to be taken is small relative to the size of the overall 
population. ``Unmitigable adverse impact'' is defined 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 (2) that cannot be sufficiently mitigated by 
other measures to increase

[[Page 58797]]

the availability of marine mammals to allow subsistence needs to be 
met.'' The subsistence provision applies to northern sea otters 
(Enhydra lutris kenyoni) in Alaska but not to southern sea otters (from 
here forward, ``sea otters'').

Summary of Request

    In July 2013, we received a request from the USCG (Applicant) for 
MMPA authorization to take by harassment southern sea otters (Enhydra 
lutris nereis) incidental to the replacement of pier piles and the 
potable water line at USCG Station Monterey in Monterey Harbor, 
California. The Applicant proposes to remove and replace 17 timber 
piles that structurally support the patrol boat pier (Pier), replace 
the existing potable water line, and improve associated structures to 
maintain the structural integrity of the Pier and potable water line. 
Pile driving activities would be limited to the period from June 15 to 
October 15, but other construction activities could occur at any time 
during the 1-year authorization window. On April 3, 2014, we were 
notified that, due to Federal funding issues affecting its contracting 
timelines, the USCG was requesting that the start date of its 1-year 
authorization window be delayed to September 2014. On June 20, 2014, we 
were notified that the USCG was requesting another delay in its start 
date, to October 15, 2014. A detailed description of the proposed 
action is contained in the incidental harassment authorization request 
submitted to us by the USCG (URS 2013). The proposed action is expected 
to result in take, by Level B Harassment only, of sea otters.

Description of the Activity

    The proposed action would involve removing the existing timber 
deck, timber stringers, steel pile caps, steel support beams, and 
hardware to access the 17 timber piles that need to be replaced. The 
timber piles, which are approximately 14 to 16 inches (in) (36 to 41 
centimeters (cm)) in diameter and covered with polyvinyl chloride (PVC) 
wraps, would be removed by means of a vibratory extractor. Each timber 
pile would be replaced with a steel pipe pile up to 18 in (46 cm) in 
diameter, with 0.5 in (1.3 cm) thick walls. Each steel pipe pile would 
be positioned and installed in the footprint of the extracted timber 
pile. The new steel pipe piles would not be filled with concrete. Other 
material and hardware removed to conduct the pile replacement would be 
replaced with in-kind materials. Due to dense substrate at the project 
site, a majority of the steel pipe pile installation would likely 
require impact pile driving, but vibratory pile driving would be 
conducted to the extent feasible, with an impact hammer used for 
proofing the piles. Pre-drilling would be permitted but discontinued 
when the pile tip is approximately 5 feet (ft) (1.5 meters (m)) above 
the required pile tip elevation. If the steel pipe pile could not be 
driven 30 ft (9 m) below the mudline with an impact hammer due to the 
substrate or jetty armor, the pile would be posted onto the armor stone 
using 36 in (91 cm) diameter concrete pedestals and dowels anchored 
into the armor stone. Concrete slurry would be used to cement stone 
within 5 ft (1.5 m) of posted steel pipe piles to further secure the 
piles.
    Pile extraction and driving equipment would not be located on the 
existing Pier but on a barge positioned in a manner that would not 
impede access to the floating docks or disrupt Pier access. The barge 
would be secured so that pedestrians would not be able to access it. 
Several proposed ancillary repairs to the Pier deck and floating dock 
are associated with this project. Specifically, under-deck repairs 
would involve restoring bearings at pedestals and sea walls with non-
shrink grout pads and replacing underwater pile struts. Above-deck 
repairs would include removing abandoned mooring hardware, replacing 
missing sections of curb, and replacing isolated deck planks that have 
deteriorated. Repairs to the floating dock would include repairing tie 
rods, repairing concrete spall, relocating and securing gangway wear 
plate(s), replacing cleats, replacing missing rubstrips, and replacing 
underwater pile struts.
    Best management practices would be employed during demolition and 
construction activities to prevent debris from falling into the water. 
A sound attenuation system (bubble curtain) would be used during impact 
hammer pile driving. The bubble curtain creates an underwater wall of 
air around the pile to dissipate in-water sound waves. The Applicant 
has proposed additional measures to reduce impacts on marine mammals. 
We discuss these measures below under ``Mitigation Measures.''
    To facilitate supplementary monitoring of effects on sea otters in 
or near the project area, the Service has requested, and the USCG has 
agreed to provide, 24-hour advance notice of pile driving activity and 
a record of the start and stop times of all pile driving activities 
once they are completed.

a. Timing of Activity

    The proposed pile extraction and driving activities would occur 
between June 15 and October 15 of 2015. Pile driving activities would 
be expected to require no more than 10 days of the total construction 
time, with a maximum of 60 to 70 minutes of pile driving occurring per 
day. In total, approximately 10 to 12 hours of underwater and airborne 
noise would be expected to result from pile driving and extraction 
activities associated with the proposed action. Other construction 
activities could occur at any time during the November 1, 2014, to 
October 31, 2015, authorization window and would likely require a 
maximum of 60 work days for completion.

b. Geographic Location of Activity

    The USCG Station Monterey is located at 100 Lighthouse Avenue, in 
the city and county of Monterey, California. The Pier is on the eastern 
portion of the USCG Station's waterfront facility, along a jetty that 
extends approximately 1,300 ft (396 m) east into Monterey Harbor. The 
Pier and floating docks are on the southern side of the jetty.

Description of Marine Mammals in the Area of the Activity

    Several species of marine mammals occur in the proposed 
construction area, including the Pacific harbor seal (Phoca vitulina 
richardsi), California sea lion (Zalophus californianus), harbor 
porpoise (Phocoena phocoena), killer whale (Orcinus orca), and gray 
whale (Eschrichtius robustus). These species are under the jurisdiction 
of the National Marine Fisheries Service and are considered under a 
separate proposed IHA notice (79 FR 13991; March 12, 2014). The only 
marine mammal species under the jurisdiction of the Service that occurs 
in the proposed construction area is the sea otter.
    Southern sea otters are listed as threatened under the Endangered 
Species Act of 1973, as amended (ESA) (42 FR 2965; January 14, 1977), 
and, because of their threatened status, are automatically considered 
``depleted'' under the MMPA. The State of California also recognizes 
the sea otter as a fully protected mammal (Fish and Game Code section 
4700) and as a protected marine mammal (Fish and Game Code section 
4500). All members of the sea otter population in California are 
descendants of a small group that survived the fur trade and persisted 
near Big Sur, California. Historically ranging from at least as far 
north as Oregon (Valentine et al. 2008) to Punta Abreojos, Baja 
California, Mexico, in the south, sea otters currently occur in only 
two areas of California. The mainland population ranges from San Mateo

[[Page 58798]]

County to Santa Barbara County, and a translocated population exists at 
San Nicolas Island. The most recent (2013) California-wide index of 
abundance is 2,941 individuals (www.werc.usgs.gov/seaottercount). 
Additional general information on status and trends of the sea otter 
may be found in the stock assessment report, available at https://www.fws.gov/ventura/endangered/species/info/sso.html.
    Sea otters occur in the Monterey Bay Harbor area year round. Census 
data for 2013 and 2014 indicate that there are, on average, three to 
four sea otters per 1,640 ft (500 m) of coastline within Monterey 
Harbor and in the immediately adjacent shoreline areas (U.S. Geological 
Survey (USGS) 2013, 2014). Figure 6-2 of URS (2013) shows the expected 
extent of attenuated underwater noise resulting from the proposed 
project to thresholds of 190, 180, and 160 decibels (dB) re 1 micro-
Pascal ([mu]Pa) root mean square (RMS). Direct observations indicate 
that approximately six independent (adult or juvenile) sea otters 
utilize the area expected to be exposed to underwater noise of 160 dB 
or higher, about half of which are adult females with pups (Staedler, 
pers. comm. 2014). Sea otters typically use this area to rest and to 
forage. In areas close to the proposed project location (within the 
modeled underwater 180 to 190 dB zone), sea otters occasionally use a 
passage through the rocks to access the kelp beds north of the jetty 
from the harbor (M. Staedler, Monterey Bay Aquarium Sea Otter Research 
and Conservation Program, pers. comm. 2014).

Potential Impacts of the Proposed Action on Sea Otters

    In this section we provide a qualitative discussion of the 
potential impacts of the proposed project. The ``Estimated Take by 
Incidental Harassment'' section later in this document includes a 
quantitative analysis of the number of individuals that may be taken by 
Level B harassment as a result of this activity.
    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). A 
permanent threshold shift (PTS) is said to occur when the loss of 
hearing sensitivity is unrecoverable, whereas a temporary threshold 
shift (TTS) is said to occur when the animal's hearing threshold 
recovers over time (Southall et al. 2007). Noise exposures resulting in 
TTS can cause PTS if repeated over time. Chronic exposure to excessive, 
but not high-intensity, noise can cause masking at the frequency band 
that some animals utilize for vital biological functions (Clark et al. 
2009). Noise can also cause other forms of disturbance when marine 
mammals alter their normal patterns of behavior to move away from the 
source.
    Relatively little is known regarding the effects of noise on sea 
otters, but they have not been reported to be particularly sensitive to 
noise disturbance, especially in comparison to other marine mammals 
(Riedman 1983, 1984). Many marine mammals depend on acoustic cues for 
vital biological functions, such as orientation, communication, 
locating prey, and avoiding predators. However, sea otters are not 
known to use acoustic information to orient or to locate prey, nor are 
they known to communicate underwater. Ghoul and Reichmuth (in press) 
obtained aerial and underwater audiograms for a captive adult male sea 
otter and evaluated his hearing in the presence of noise. In air, the 
sea otter's hearing was similar to that of a sea lion but less 
sensitive to high-frequency (greater than 22 kHz) and low-frequency 
(less than 2 kHz) sounds than terrestrial mustelids. Underwater, the 
sea otter's hearing was less sensitive than that of sea lions and other 
pinnipeds, particularly at frequencies below 1 kHz. Critical ratios 
were more than 10 dB above those measured in pinnipeds, suggesting that 
sea otters have a relatively poor capacity to detect acoustic signals 
in noise.
    Observed responses of wild sea otters to disturbance are highly 
variable, probably reflecting the level of noise and activity to which 
they have been exposed and become acclimated over time and the 
particular location and social or behavioral state of that individual 
(G. Bentall, Monterey Bay Aquarium Sea Otter Research and Conservation 
Program, pers. comm. 2010). Sea otters appeared to be relatively 
undisturbed by pile driving activities in Elkhorn Slough during the 
construction of the Parsons Slough Sill, with many showing no response 
to pile driving and generally reacting more strongly to passing vessels 
associated with construction than to the sounds of machinery (Elkhorn 
Slough National Estuarine Research Reserve (ESNERR) 2011). However, 
these animals were likely acclimated to loud noises, as they occupied 
an area near an active railroad track, which produced in-air sound 
levels comparable to those produced by the vibratory driving of H piles 
(ESNERR 2011).
    The most likely effect of the proposed project on sea otters is 
behavioral disturbance due to construction noise and activity. 
Potentially affected areas include the harbor and the area immediately 
north of the jetty. Underwater and airborne noise generated by pile 
replacement work may cause sea otters that rest or forage within or 
near the harbor to relocate temporarily to nearby areas. Behavioral 
changes resulting from disturbance could include startle responses, the 
interruption of resting behaviors (while in-water or hauled out on 
nearby docks), and changes in foraging patterns. Most likely, sea 
otters would move away from the noise source and would be temporarily 
displaced from the pile replacement work area.
    The National Marine Fisheries Service (NMFS) employs acoustic 
exposure criteria to define Level A harassment (injury) and Level B 
harassment (disturbance) resulting from sound for the marine mammal 
species under its jurisdiction. For underwater noise, NMFS currently 
uses 180 and 190 dB re 1 [mu]Pa (received levels) as the thresholds for 
Level A harassment of cetaceans and pinnipeds, respectively. NMFS uses 
120 and 160 dB re 1 [mu]Pa (received levels) as the thresholds for 
Level B harassment due to non-impulsive (vibratory pile driving and 
removal) and impulsive (impact pile driving) sources, respectively, for 
both cetaceans and pinnipeds. For airborne noise, NMFS uses 90 and 100 
dB re 20 [mu]Pa (received levels) as a guideline (but not formal 
threshold) for the onset of Level B harassment for harbor seals and all 
other pinnipeds, respectively (79 FR 13991; March 12, 2014). NMFS does 
not have a guideline for the onset of Level A harassment of pinnipeds 
by airborne noise (A. Scholik-Schlomer, Office of Protected Resources, 
Marine Mammal and Sea Turtle Conservation Division, pers. comm. 2014). 
However, Southall et al. (2007) propose an injury criterion for sea 
lions exposed to airborne noise of 172.5 dB re 20 [mu]Pa.
    In the absence of sufficient data on which to base noise exposure 
thresholds specific to sea otters, but in light of evidence suggesting 
that the hearing sensitivities of sea lions and sea otters are 
generally comparable (although underwater, sea otter hearing appears to 
be less sensitive than sea lion hearing), we use the thresholds, 
guidelines, and criteria applicable to sea lions as proxies. With 
regard to underwater noise, we use the thresholds adopted by NMFS for 
pinnipeds (e.g., sea lions) to evaluate whether noise exposure levels 
would constitute Level A or Level B harassment of sea otters. With 
regard to

[[Page 58799]]

airborne noise, we use the guideline that NMFS uses for pinnipeds other 
than harbor seals to evaluate whether anticipated exposure levels 
resulting from this project would constitute Level B harassment of sea 
otters and the injury criterion proposed in Southall et al. (2007) for 
sea lions to evaluate whether the anticipated airborne noise exposures 
would constitute Level A harassment. Specifically, we use 190 dB re 1 
[mu]Pa as the threshold for Level A harassment underwater and 120 dB re 
1 [mu]Pa (for non-impulse sources) and 160 dB re 1 [mu]Pa (for impulse 
sources) as the thresholds for Level B harassment underwater. 
Similarly, we adopt for sea otters the 100 dB re 20 [mu]Pa guideline 
that NMFS uses for in-air Level B harassment of pinnipeds other than 
harbor seals. We use the Southall et al. (2007) criterion of 172.5 dB 
re 20 [mu]Pa for sea lions to approximate the airborne noise levels 
that may cause injury to sea otters.

Potential Effects of the Proposed Action on Sea Otter Habitat

    No permanent impacts on habitat are proposed or would occur as a 
result of this project. The Proposed Action would not increase the 
Pier's existing footprint, and no new structures would be installed 
that would result in the loss of additional habitat. Therefore, no 
restoration of habitat would be necessary. A temporary, small-scale 
loss of foraging habitat may occur if sea otters leave the area during 
pile extraction and driving activities.

Potential Impacts on Subsistence Needs

    The subsistence provision of the MMPA does not apply.

Mitigation Measures

    The USCG has proposed the following measures to prevent Level A 
harassment (injury) and to reduce the extent of potential effects from 
Level B harassment (disturbance) to marine mammals.
    1. Noise attenuation: Noise attenuation systems (i.e., bubble 
curtains) would be used during all impact pile driving to interrupt the 
acoustic pressure and reduce the impact on marine mammals. By reducing 
underwater sound pressure levels at the source, bubble curtains would 
minimize the size of the Level A harassment exclusion zone and reduce 
the area within which Level B harassment would occur, thereby 
minimizing the number of sea otters affected.
    2. Establishment of Level A and Level B harassment zones based on 
in-water and in-air empirical sound measurements of pile driving and 
removal: A Level A harassment exclusion zone would include all areas 
where underwater sound pressure levels were expected to reach or exceed 
190 dB re 1 [micro]Pa. Modeled distances to the 190 dB isopleth are 33 
ft (10 m) or less for attenuated noise and 75 ft (23 m) or less for 
unattenuated noise. To provide a margin of safety, a provisional 
conservative exclusion zone would be established during initial pile 
extraction and driving efforts while hydroacoustic measurements were 
made to establish actual field conditions. A bubble curtain would be 
employed, but during initial pile extraction and driving, the exclusion 
zone would be set at the modeled distances for unattenuated noise. The 
Level A and Level B harassment zones would be adjusted, in consultation 
with NMFS and the Service, once field conditions for impulse and non-
impulse noise sources were established through hydroacoustic 
monitoring. Airborne noise monitoring would also be conducted to ensure 
that noise levels were consistent with those anticipated. Regardless of 
the results of field measurements, the radius of the Level A exclusion 
zone would be a minimum of 33 ft (10 m) to prevent the injury of sea 
otters from machinery. An exclusion zone of this radius would also 
preclude the possibility that sea otters could be exposed to airborne 
noise levels with the potential to cause injury. Airborne noise levels 
from pile driving at a distance of 33 ft (10 m) from the source are 
expected to be 104 dB re 20 [micro]Pa for vibratory driving and 116 dB 
re 20 [micro]Pa for impact driving (K. Bayer, URS, pers. comm. 2014). 
These noise levels are well below the potential threshold for injury, 
172.5 dB re 20 [micro]Pa.
    3. Visual monitoring and shutdown procedures: The exclusion zone 
would be monitored visually prior to any pile extraction and driving 
activities to ensure that the area was clear of any sea otters. Pile 
extraction or driving would not commence (or re-commence following a 
shutdown) until sea otters were not sighted within the exclusion zone 
for a 15-minute period. If a sea otter entered the exclusion zone 
during pile replacement work, work would stop until the animal left the 
exclusion zone. Monitoring would be conducted by qualified observers 
familiar with marine mammal species, including sea otters, and their 
behavior. The observer would monitor the exclusion zone from the best 
vantage point possible (the Pier itself, the jetty, or adjacent boat 
docks in the harbor) to determine whether sea otters entered the 
exclusion zone.
    4. Soft-start procedures: A ``soft-start'' technique would be used 
to allow sea otters to vacate the area before the pile driver reached 
full power. For vibratory hammers, the contractor would initiate the 
driving or extraction for 15 seconds at reduced energy, followed by a 
1-minute waiting period. This procedure would be repeated two 
additional times before continuous driving or extraction proceeded. For 
impact driving, an initial set of three strikes would be made by the 
hammer at 40 percent energy, followed by a 1-minute waiting period and 
two subsequent three-strike sets before the initiation of continuous 
driving. A soft start would be used in any instance following a down 
time of 30 minutes or more.
    5. Daylight construction period: Work would occur only during 
daylight hours (7 a.m. to 7 p.m.) to facilitate visual observation of 
the exclusion zone.

Monitoring and Reporting

    The USCG would follow two detailed monitoring plans: One for 
conducting acoustic measurements and one for documenting marine mammal 
observations. The acoustic monitoring plan would ensure that 
measurements are recorded to provide data on actual noise levels during 
construction and provide data to ensure that the marine mammal 
exclusion zone is enforced during pile extraction and driving 
activities. The marine mammal monitoring plan would provide details on 
data collection for each marine mammal species observed in the project 
area during the construction period. Monitoring would include the 
following: Marine mammal behavior observations, count of the 
individuals observed, and the frequency of the observations.

Acoustic Monitoring

    Both underwater and airborne noise would be measured. Hydroacoustic 
monitoring would be conducted by a qualified monitor during pile 
extraction and driving activities. Details would be developed during 
work plan preparation, but could include monitoring one pile in every 
set of three piles during installation. A reference location would be 
established at the estimated 180 dB contour (approximately 330 ft (100 
m) from the pile). Noise measurements would be taken at the reference 
location and at locations every 20 ft (6 m) until the 180 dB level 
(Level A threshold) is found. Measurements would be taken at two 
depths: One in mid-water column, and one near the bottom but at least 3 
ft (0.9 m) above the bottom. Marine mammal exclusion zones would be 
adjusted according to the results of this monitoring. Additional 
acoustical

[[Page 58800]]

monitoring details would be developed in conjunction with NMFS and the 
Service prior to the start of construction.
    Airborne noise monitoring would be conducted at two locations. One 
location would be at 49 to 98 ft (15 to 30 m) from the pile driving 
operation to provide near-source noise measurements. This location 
would likely be a fixed position with an intended clear view of pile 
driving operations. The second system would be established at the haul-
out area on the jetty. The actual position would be determined in the 
field, depending on access and security issues. This position is 
anticipated to be 262 to 492 ft (80 to 150 m) from the piles driven. 
Airborne sound levels would be continuously monitored for the duration 
of pile extraction or installation. The maximum 1/8th second average 
(i.e., Lmax) of each 1 second (or pile strike) and the 
energy average level (Leq) for each pile would be measured 
in real time. Airborne sound levels would be measured in decibels 
referenced to 20 [mu]Pa.

Marine Mammal Monitoring and Reporting

    The USCG would employ protected species observers trained in marine 
mammal identification and behavior and approved by NMFS and the 
Service.
     Biological monitoring would occur on two separate days 
within one week before the first day of construction to establish 
baseline observations. Baseline observations would be used for 
comparison with observations during pile driving and removal 
activities.
     Monitoring for marine mammal presence would commence 30 
minutes before any pile driving or removal activities and conclude 30 
minutes after any pile driving or removal activities.
     Monitoring of marine mammals around the construction site 
would be conducted using high-quality binoculars as necessary (e.g., 
Zeiss, 10 x 42 power).
     Marine mammal visual monitoring would occur from the best 
vantage points available, including the USCG Pier, jetty, adjacent 
docks within the harbor, or watercraft, in order to maintain a 
comprehensive view of the exclusion zone and adjacent areas during the 
survey period. Monitors would be equipped with radios or cell phones 
for maintaining contact with work crews.
     Vessel-based visual marine mammal monitoring within the 
120 dB and 160 dB level B harassment zones would be conducted during 10 
percent of the vibratory pile driving and removal and impact pile 
driving activities, respectively.
     Data collection would consist of a count of all marine 
mammals by species, a description of behavior (if possible), location, 
direction of movement, type of construction that is occurring, time 
that pile replacement work begins and ends, any acoustic or visual 
disturbance, and time of the observation. Environmental conditions such 
as weather, visibility, temperature, tide level, current, and sea state 
would also be recorded.
     Weekly monitoring reports that summarize the monitoring 
results, construction activities, and environmental conditions would be 
submitted to NMFS and the Service.
     A final report would be submitted to NMFS and the Service 
within 90 days after completion of the proposed project.
     The Service would require the USCG to notify the Service's 
Ventura Fish and Wildlife Office and the Monterey Bay Aquarium by 
telephone within one hour of sighting an injured sea otter in the 
vicinity of the construction site, or within 24 hours of sighting a 
dead sea otter in the vicinity of the construction site. The USCG would 
be required to provide a description of the condition of the animal(s) 
or carcass(es), location, time of discovery, observed behavior (if 
alive), and photographic or video documentation, if available. In the 
unanticipated event that the construction activities clearly caused the 
injury or death of a sea otter, the USCG would be required immediately 
to suspend all activities and immediately to report the incident by 
telephone to the Service's Ventura Fish and Wildlife Office and the 
Monterey Bay Aquarium. The USCG would not be permitted to resume 
activities until notified by the Service by email, letter, or 
telephone.

Estimated Take by Incidental Harassment

    Based on the proposed construction methodology and mitigation, 
including use of an exclusion zone, no Level A harassment is 
anticipated as a result of the proposed project. Behavioral harassment 
(Level B) will be considered to have occurred when sea otters are 
exposed to (1) in-air noise of 100 dB or greater or (2) underwater 
noise of 160 dB RMS or greater for impulse noise (impact pile driving) 
and 120 dB RMS for continuous noise (vibratory pile extraction and 
driving). For continuous noise, RMS levels are based on a time constant 
of 10 seconds, and those RMS levels should be averaged across the 
entire event. For impact pile driving, the overall RMS level should be 
characterized by integrating sound energy for each acoustic pulse 
across 90 percent of the acoustic energy in each pulse, and averaging 
all the RMS levels for all pulses.

    URS (2013) estimated the number of exposures of sea otters to 
underwater and airborne sound, using a formula based on the following 
assumptions:
     All piles to be installed would have a noise disturbance 
distance equal to the pile that causes the greatest noise disturbance 
(i.e., the piling furthest from shore, in this case the easternmost 
pile along the jetty).
     An average of two or three piles would be installed and 
removed per day. The best estimate of the number of days during which 
pile driving would occur is 10 days, and this was used in all modeling 
calculations.
     Mitigation (e.g., a noise attenuation system such as a 
bubble curtain) would be used during impact pile driving.
     An individual sea otter can only be taken once per method 
of installation during a 24-hour period.

URS (2013) calculated the number of exposures using the following 
formula: Take Estimate = n multiplied by AOI multiplied by 10 days of 
activity, where: n (number of animals per unit area) is the density 
estimate used for each species (for the sea otter, the unit of area is 
linear km of coastline) and AOI (area of influence) is the area 
encompassed by all locations where the sound pressure levels equal or 
exceed the threshold being evaluated. Multiplying n by AOI produces an 
estimate of the abundance of animals that could be present in the area 
of exposure per day. Because the final take estimate must be a whole 
number, values are rounded up to the next whole number.
    The AOI impact is the estimated range of noise impact for a given 
threshold. Because the work will be conducted near the jetty, 
underwater noise is not expected to spread spherically from the source. 
Underwater noise contours were therefore modeled using SoundPlan. The 
contours were then imported to ArcGIS to calculate the area within the 
contours and determine the AOI for each threshold. The AOI for 
vibratory pile driving encompasses the area out to the 120 dB isopleth 
(Level B threshold), while the AOI for impact driving encompasses the 
area out to the 160 dB isopleth (Level B threshold). It is assumed that 
an underwater noise attenuation system, such as a bubble curtain with 
an estimated 10 dB attenuation, would be used as a mitigation measure. 
However, the actual attenuation that will be achieved in the field is 
unknown and would likely vary

[[Page 58801]]

with each installation. Airborne noise would spread spherically from 
the source; therefore, the AOI for airborne impacts was calculated as 
the area within a circle (Area = pi multiplied by radius squared).
    Although 10 days of total in-water work are proposed, pile 
extraction or driving would only occur periodically during that time. 
An average work day (beginning 2 hours after sunrise and ending 2 hours 
before sunset) is approximately 8 to 9 hours, depending on the month. 
Although it is anticipated that only 60 to 70 minutes would be spent 
pile driving per day, to take into account deviations from the 
estimated times for pile installation and extraction, and to account 
for the additional use of the impact pile driver in case of failure of 
the vibratory hammer to reach the desired embedment depth, the 
potential impacts were modeled as if the entire day could be spent pile 
driving.
    Based on these assumptions and an abundance of 8 sea otters per 
0.62 mile (1 kilometer) of coastline for the Monterey Harbor and 
adjacent areas (USGS 2012), URS estimated that during 10 days of pile 
driving, there could be 44 exposures to underwater sound within the 160 
dB threshold zone for impact driving, 480 exposures to underwater sound 
within the 120 dB threshold zone for vibratory driving, 10 exposures to 
airborne sound resulting from impact driving, and 4 exposures to 
airborne sound resulting from vibratory driving (URS 2013). 
Approximately 8 sea otters occur in the area that would be exposed to 
impulsive underwater noise of 160 dB or greater, and approximately 48 
sea otters occur within the entire area that could be exposed to 
project-related sound exceeding the Level B harassment thresholds 
(defined by the 120 dB threshold for continuous underwater noise, which 
is larger than and encompasses all other threshold zones).
    Thus, we expect 44 potential exposures (for up to 8 otters) within 
the 160 dB (underwater impulsive) threshold zone and 494 potential 
exposures (for up to 48 otters) within the 120 dB (underwater 
continuous) or 100 dB (airborne) threshold zones.

Findings

    We propose the following findings regarding this action:

Negligible Impact

    We find that any incidental take by harassment that is reasonably 
likely to result from the proposed project would not adversely affect 
the sea otter by means of effects on rates of recruitment or survival, 
and would, therefore, have no more than a negligible impact on the 
stock. In making this finding, we considered the best available 
scientific information, including: (1) The biological and behavioral 
characteristics of the species; (2) information on distribution and 
abundance of sea otters within the area of the proposed activity; (3) 
the potential sources of disturbance during the proposed activity; and 
(4) the potential response of sea otters to disturbance.
    The estimated 44 potential exposures (for up to 8 otters) within 
the 160 dB (underwater impulsive) threshold zone and 494 potential 
exposures (for up to 48 otters) within the 120 dB (underwater 
continuous) or 100 dB (airborne) threshold zones are expected to result 
in negligible impact, because sea otters do not appear to be 
particularly sensitive to noise (and often do not react visibly to it) 
and because any behavioral reactions to noise are expected to be 
temporary and of short duration. In particular, the estimate of the 
number of sea otters that would be harassed by exposure to project-
related sound based on the 120 dB threshold may overstate impacts, 
because this threshold is sometimes at or even below the ambient noise 
level in certain locations. For instance, Illingworth & Rodkin, Inc., 
measured ambient noise levels in the Monterey Harbor in the project 
area and found that ambient sounds were in the 110 to 120 dB range, 
with frequent acoustic events, such as boat traffic, resulting in sound 
levels that exceeded 120 dB (URS 2013, Appendix A).
    The mitigation measures outlined above are intended to minimize the 
number of sea otters that could be disturbed by the proposed activity. 
Any impacts to individuals are expected to be limited to Level B 
harassment of short duration. Responses of sea otters to disturbance 
would most likely be common behaviors such as diving and/or swimming 
away from the source of the disturbance. No take by injury or death is 
anticipated. Because any Level B harassment that occurs would be of 
short duration, and because no take by injury or death is anticipated, 
we find that the anticipated harassment caused by the proposed 
activities is not expected to adversely affect the species or stock 
through effects on annual rates of recruitment or survival.
    Our finding of negligible impact applies to incidental take 
associated with the proposed activity as mitigated through this 
authorization process. This authorization establishes monitoring and 
reporting requirements to evaluate the potential impacts of the 
authorized activities, as well as mitigation measures designed to 
minimize interactions with, and impacts to, sea otters.

Small Numbers

    For small numbers take analysis, the statute and legislative 
history do not expressly require a specific type of numbers analysis, 
leaving the determination of ``small'' to the agency's discretion. The 
sea otter population in California consists of approximately 2,941 
animals. The number of sea otters that could potentially be taken by 
harassment in association with the proposed project, approximately 48 
animals, is 1.6 percent of the population size. We find that the number 
of sea otters utilizing the affected area is small relative to the size 
of the population.

Impact on Subsistence

    The subsistence provision of the MMPA does not apply to southern 
sea otters.

Endangered Species Act

    The proposed activity will occur within the range of the southern 
sea otter, which is listed as threatened under the ESA. The Applicant 
has initiated interagency consultation under section 7 of the ESA with 
the Service's Ventura Fish and Wildlife Office. We will also complete 
intra-Service section 7 consultation on our proposed issuance of the 
IHA.

National Environmental Policy Act (NEPA)

    The impacts associated with the project are described in a final EA 
prepared on behalf of the USCG (URS 2014). The Service will review the 
EA and decide either to adopt it or prepare its own NEPA document 
before making a determination on the issuance of an IHA. Our analysis 
will be completed prior to issuance or denial of the IHA and will be 
available at https://www.fws.gov/ventura/endangered/species/info/sso.html.

Government-to-Government Relations With Native American Tribal 
Governments

    In accordance with the President's memorandum of April 29, 1994, 
``Government-to-Government Relations with Native American Tribal 
Governments'' (59 FR 22951), Executive Order 13175, Secretarial Order 
3225, and the Department of the Interior's manual at 512 DM 2, we 
readily acknowledge our responsibility to communicate meaningfully with 
federally recognized Tribes on a Government-to-Government basis. We

[[Page 58802]]

have evaluated possible effects on federally recognized Indian Tribes 
and have determined that there are no effects.

Proposed Authorization

    The Service proposes to issue an IHA for small numbers of sea 
otters harassed incidentally by the Applicant while the applicant is 
completing waterfront repairs at USCG Station Monterey, with a 1-year 
authorization window beginning November 1, 2014, and ending October 31, 
2015. Authorization for incidental take beyond this period would 
require a request for renewal.
    The final IHA would incorporate the mitigation, monitoring, and 
reporting requirements discussed in this proposal. The Applicant would 
be responsible for following those requirements. These authorizations 
would not allow the intentional taking of sea otters.
    If the level of activity exceeded that described by the Applicant, 
or the level or nature of take exceeded those projected here, the 
Service would reevaluate its findings. The Secretary may modify, 
suspend, or revoke an authorization if the findings are not accurate or 
the conditions described in this notice are not being met.

Request for Public Comments

    The Service requests interested persons to submit comments and 
information concerning this proposed IHA. Consistent with section 
101(a)(5)(D)(iii) of the MMPA, we are opening the comment period on 
this proposed authorization for 30 days (see DATES).
    Before including your address, phone number, email address, or 
other personal identifying information in your comment, you should be 
aware that your entire comment--including your personal identifying 
information--may be made publicly available at any time. While you can 
ask us in your comment to withhold your personal identifying 
information from public review, we cannot guarantee that we will be 
able to do so.

    Dated: September 23, 2014.
Polly Wheeler,
Acting Deputy Regional Director, Pacific Southwest Region.
[FR Doc. 2014-23233 Filed 9-29-14; 8:45 am]
BILLING CODE 4310-55-P