Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Astoria Waterfront Bridge Replacement Phase 2 Project
| Published date | 06 November 2019 |
| Record Number | 2019-24190 |
| Section | Notices |
| Court | National Oceanic And Atmospheric Administration |
Federal Register, Volume 84 Issue 215 (Wednesday, November 6, 2019)
[Federal Register Volume 84, Number 215 (Wednesday, November 6, 2019)]
[Notices]
[Pages 59773-59794]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-24190]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN 0648-XR043
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to Astoria Waterfront Bridge
Replacement Phase 2 Project
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice; proposed incidental harassment authorization; request
for comments on proposed authorization and possible renewal.
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SUMMARY: NMFS has received a request from the City of Astoria (City)
for authorization to take marine mammals incidental to pile driving and
construction work in Astoria, OR. Pursuant to the Marine Mammal
Protection Act (MMPA), NMFS is requesting comments on its proposal to
issue an incidental harassment authorization (IHA) to incidentally take
marine mammals during the specified activities. NMFS is also requesting
comments on a possible one-year renewal that could be issued under
certain circumstances and if all requirements are met, as described in
Request for Public Comments at the end of this notice. NMFS will
consider public comments prior to making any final decision on the
issuance of the requested MMPA authorizations, and agency responses
will be summarized in the final notice of our decision.
DATES: Comments and information must be received no later than December
6, 2019.
ADDRESSES: Comments should be addressed to Jolie Harrison, Chief,
Permits and Conservation Division, Office of Protected Resources,
National Marine Fisheries Service. Physical comments should be sent to
1315 East-West Highway, Silver Spring, MD 20910 and electronic comments
should be sent to [email protected].
Instructions: NMFS is not responsible for comments sent by any
other method, to any other address or individual, or received after the
end of the comment period. Comments received electronically, including
all attachments, must not exceed a 25-megabyte file size. Attachments
to electronic comments will be accepted in Microsoft Word or Excel or
Adobe PDF file formats only. All comments received are a part of the
public record and will generally be posted online at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities without change. All
personal identifying information (e.g., name, address) voluntarily
submitted by the commenter may be publicly accessible. Do not submit
confidential business information or otherwise sensitive or protected
information.
FOR FURTHER INFORMATION CONTACT: Leah Davis, Office of Protected
Resources, NMFS, (301) 427-8401. Electronic copies of the application
and supporting documents, as well as a list of the references cited in
this document, may be obtained online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities. In case of problems
accessing these documents, please call the contact listed above.
SUPPLEMENTARY INFORMATION:
Background
The MMPA prohibits the ``take'' of marine mammals, with certain
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to
allow, upon request, the incidental, but not intentional, taking of
small numbers of marine mammals by U.S. citizens who engage in a
specified activity (other than commercial fishing) within a specified
geographical region if certain findings are made and either regulations
are issued or, if the taking is limited to harassment, a notice of a
proposed incidental take authorization may be provided to the public
for review.
Authorization for incidental takings shall be granted if NMFS finds
that the taking will have a negligible impact on the species or
stock(s) and will not have an unmitigable adverse impact on the
availability of the species or stock(s) for taking for subsistence uses
(where relevant). Further, NMFS must prescribe the permissible methods
of taking and other ``means of effecting the least practicable adverse
impact'' on the affected species or stocks and their habitat, paying
particular attention to rookeries, mating grounds, and areas of similar
significance, and on the availability of such species or stocks for
taking for certain subsistence uses (referred to in shorthand as
``mitigation''); and requirements pertaining to the mitigation,
monitoring and reporting of such takings are set forth.
The definitions of all applicable MMPA statutory terms cited above
are included in the relevant sections below.
National Environmental Policy Act
To comply with the National Environmental Policy Act of 1969 (NEPA;
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A,
NMFS must review our proposed action (i.e., the issuance of an
incidental harassment authorization) with respect to potential impacts
on the human environment. This action is consistent with categories of
activities identified in Categorical Exclusion B4 (incidental
harassment authorizations with no anticipated serious injury or
mortality) of the Companion Manual for NOAA Administrative Order 216-
6A, which do not individually or cumulatively have the potential for
significant impacts on the quality of the human environment and for
which we have not identified any extraordinary circumstances that would
preclude this categorical exclusion. Accordingly, NMFS has
preliminarily determined that the issuance of the proposed IHA
qualifies to be categorically excluded from further NEPA review.
We will review all comments submitted in response to this notice
prior to concluding our NEPA process or making a final decision on the
IHA request.
Summary of Request
On June 3, 2019 NMFS received a request from the City of Astoria
(City) for an IHA to take marine mammals incidental to pile driving and
construction work in Astoria, Oregon. The application was deemed
adequate and complete on October 17, 2019. The
[[Page 59774]]
City's request is for take of a small number of California sea lion
(Zalophus californianus) and harbor seal (Phoca vitulina richardii) by
Level A and Level B harassment, and a small number of Steller sea lion
(Eumetopias jubatus) by Level B harassment only. Neither the City nor
NMFS expects serious injury or mortality to result from this activity,
and, therefore, an IHA is appropriate.
This proposed IHA would cover one year of a larger, two-year
project that involves removal and replacement of six bridges on the
Astoria, Oregon waterfront. NMFS previously issued an IHA to the City
for removal and replacement of three bridges (83 FR 19243, May 2,
2018). The City complied with all the requirements (e.g., mitigation,
monitoring, and reporting) of the previous IHA and information
regarding their monitoring results may be found in the Proposed
Monitoring and Mitigation Section. The monitoring report exposed the
need for clarification of monitoring requirements, specifically those
involving Protected Species Observer (PSO) coverage of Level A and
Level B zones. NMFS has clarified those requirements with the
applicant.
Description of Proposed Activity
Overview
The City of Astoria, Oregon proposes to remove and replace three
bridges connecting 6th, 8th, and 10th Streets with waterfront piers
near the mouth of the Columbia River. The bridges are currently
supported by decayed timber piles. Among all three bridges, an
estimated 150 timber piles will be removed as will other timber
structural elements and concrete footings. 65 temporary 36-inch steel
casings will be installed to help guide the installation of 65
permanent 24-inch steel piles. Pile driving and removal activities will
be conducted using a vibratory and impact hammer. The contractor may
need to conduct preboring inside of the temporary casings using a
vibratory hammer and a 14-inch H-pile to prepare the new pile sites. In
the event that preboring is not effective, the contractor may conduct
down-the-hole drilling inside of the 36-inch piles to prepare the site
for the permanent piles. It is unlikely that the contractor will need
to conduct down-the-hole drilling, as it was not necessary during Phase
1. The roadway and railway superstructures will also be replaced, and a
temporary, above-water work platform will be created for the
construction. The use of vibratory and impact hammers for pile driving
and site preparation is expected to produce underwater sound at levels
that may result in behavioral harassment or auditory injury of marine
mammals. Human presence and use of general construction equipment may
also lead to behavioral harassment of sea lions hauled out along the
riverbank below the bridges.
The impacted area extends outward from the three bridge sites to a
maximum distance of 21.54 km (13.28 mi). The project will occur over
one year beginning in December 2019, with in-water activities expected
to occur over an estimated 21 days during the months of November
through April.
Dates and Duration
The IHA will be effective from December 2019 to October 2020.
Project work is expected to begin in November 2019 with concurrent
above-water and in-water demolition activities. In-water activities
will be conducted during the Oregon Department of Fish and Wildlife-
prescribed in-water work period (IWWP) for the Lower Columbia River
(November-February). The IWWP is imposed to protect the following
species: MAR (various marine species of fish), SHL (various marine
shell fish), CHF (Chinook salmon, fall), CHS (Chinook salmon, spring),
SS (sockeye salmon), CO (coho salmon), STW (steelhead winter), STS
(steelhead summer), CT (cutthroat trout--including sea run). It is
possible that the City will request an IWWP extension through April.
In-water construction activities will occur intermittently over the
entire proposed IWWP, and above-water work is expected to occur during
the IWWP and over the remainder of the IHA period. Work will take place
over approximately 21 in-water work days, and 11 days per month for
over-water activities.
Specific Geographic Region
The project site is located in the Baker Bay-Columbia River sub-
watershed near the mouth of the Columbia River. This section of the
lower Columbia River represents the most saline portion of the river's
estuarine environment. Tidal influence extends 146 miles upriver to the
Bonneville Dam (LCEP, 2016). The Columbia River is over nine miles wide
in the area around Astoria and contains multiple islands, buoys, and
sandbars that marine mammals utilize to haul out. The upland portions
of the region of activity have been highly altered by human activities,
with substantial shoreline development and remnants of historical
development. This includes thousands of timber piles, overwater
buildings, a railroad trestle, and vehicular bridges. The downtown
Astoria waterfront is a busy area for pedestrians, vehicles, and boats.
In addition to onshore development, the lower Columbia River is
utilized by various types of vessels, including cargo ships, dredging
vessels, fishing vessels, trawlers, pollution control vessels, and
search and rescue vessels, among others. The remainder of the region of
activity is located within the river channel within the intertidal and
subtidal zones. The substrate in this area is primarily made up of
historical rip rap and other rocks/cobbles.
All in-water construction will occur in the intertidal and subtidal
zones. Some piles may be removed and installed completely in the dry
while others may be in water more than 75 percent of the time.
[[Page 59775]]
[GRAPHIC] [TIFF OMITTED] TN06NO19.000
Detailed Description of Specific Activity
Phase two of the project involves the removal and replacement of
three bridges connecting 6th, 8th, and 10th Streets to waterfront
piers.
Demolition Activities--Demolition of the existing bridge crossings
will require the removal of the bridge decks and other above-ground
components for the trestle crossings and roadway approaches. Demolition
of the superstructures will likely be accomplished using standard
roadway and bridge construction equipment, including an excavator,
backhoe, jackhammer, and concrete and chain saws, as well as a crane
will be used to remove larger timber elements. Source levels for these
equipment are included in Table 1. Source levels are mostly based on
acoustic data collected during the City of San Diego Lifeguard Station
Demolition and Construction Monitoring project. All equipment will be
operated from the existing roadway, trestle, and upland areas, and
removed materials will be hauled off-site to an approved upland
location for disposal.
Table 1--Superstructure Construction Equipment Sound Source Levels
------------------------------------------------------------------------
Peak source
level (dB root
Equipment mean squared Reference
(RMS)) at 20
meters)
------------------------------------------------------------------------
Air Compressor................. 78 WSDOT, 2016.
Backhoe........................ 78 Hanan & Associates,
2014.
Chain Saw...................... 78
Concrete Saw................... 93
Crane.......................... 89
Excavator...................... 91
Generator Powered Jackhammer... 87
Hand Tools..................... 85
------------------------------------------------------------------------
Construction activities associated with removal of the roadway
approach superstructures will be situated away from the river.
Buildings and other above-grade structures will reduce noise by
physically blocking it and reflecting it away from the river, due to
structural noise reduction (FHWA, 2011). The pier structures will also
block noise from reaching the river and bank areas by deflecting it
upwards. Based on the sound levels produced by the proposed equipment,
existing site conditions, the likely location of the pinnipeds within
the area in relation to the associated construction activities, and
Phase 1 monitoring, removal of the roadway approach superstructures is
not expected to disturb nearby marine mammals, and will not be
considered further.
At each of the three bridge sites, the City will remove
approximately 50 existing 14-inch timber piles (Table 2) using a
vibratory hammer and via direct pull. Abandoned, cutoff timber piles
that are located within close proximity to proposed pile locations will
also be removed. Old pilings are often in very poor condition near and
above the ground surface, making attachment to the pilings for
extraction very difficult. Old vertical piles and other obstructions
encountered near the surface may need to be extracted or cut below the
ground surface elevation per Federal Aid Highway Program (FAHP)
programmatic criteria. Due to uncertainty in the precise timing of
extraction, and therefore the tidal state, all piles are assumed to be
in-water during removal in effort to conduct a conservative analysis of
the project impacts.
[[Page 59776]]
The City estimates it will remove approximately 15 additional
structural elements at each bridge site, consisting of the timber
columns, bottom plates, lower braces and/or cross bracings. These
elements will be removed during low tides and will not require the use
of a vibratory hammer. Standard construction equipment will be used to
remove these elements.
In addition to the timber substructures, an estimated seven
concrete footings will need to be extracted, two at the 8th Street
bridge, and five at the 10th Street bridge. It is anticipated that the
contractor will use an excavator, positioned on the existing roadway or
adjacent gravel/asphalt parking areas, to reach down and remove the
concrete footings. If the vertical or horizontal distance makes a
footing unreachable, the contractor will likely drill an anchor into
the concrete then attach the crane to the anchor with a chain and pull
upwards to extract the concrete. The existing concrete footings are
located just below/above the MHHW elevation, so this work is likely to
occur in the dry during low tides.
The contractor will set up temporary work containment systems to
catch debris during demolition activities. Selection of the appropriate
equipment and design of the work containment systems is the
responsibility of the contractor; however, additional pilings to
support these structures are not anticipated as the contractor will
utilize the existing substructure to support them.
Site Preparation for New Bridges--A total of 65 permanent, 24-inch
steel piles are proposed for this project, as well as installation and
removal of 65 temporary 36-inch steel casings (Table 2). The contractor
is likely to create a template to facilitate pile installation. The
template will consist of a grid pattern in-line with the existing
boardwalk grade comprised of steel H-piles and steel angle iron/
channels, among other materials. The template will guide the vibratory
installation of 36-inch temporary casings at the locations of all new
24-inch steel piles.
A variety of large debris and fill may be present at the pile
sites, given the history of the area, results from the preliminary
geotechnical investigation during which most of the borings encountered
riprap, and Phase 1 construction. To avoid inducing unacceptable
vibration levels on adjacent structures, the contractor may predrill
the piling locations to an elevation of about 3 feet below
mean sea level (msl); though the need to predrill will be determined
on-site once the contractor has identified the exact pile locations.
Predrilling work, also referred to as down-the-hole drilling, would be
conducted inside the 36-inch temporary casings, and no sediment will be
removed from within the temporary casing during this site preparation
activity. The source level for down-the-hole drilling (166.2dB RMS SPL,
Denes et al., 2016) is below the source level for vibratory
installation of 36'' piles (Table 6). Predrilling was not required
during Phase 1 of the project, and the applicant considers it unlikely
for this phase; therefore, the analysis for vibratory installation of
36-inch piles was used to estimate the Level B harassment zone for
potential down-the-hole drilling, and the impact installation of 24-
inch piles was used to estimate the Level A harassment zone. (See
additional explanation in the Ensonified Area section below.) If pre-
drilling is not required, the contractor may use a 14-inch H-pile
equipped with a torched point at the end to break up the ground at each
piling location using the vibratory hammer. The H-pile site preparation
was used in Phase 1. The contractor may also manually remove riprap and
other obstructions from the riverbed and banks, if such materials
prohibit the installation of the temporary casings and permanent
pilings.
Bridge Design--The 6th Street Bridge will require a total of 21
plumb piles. Estimated pile depths range from -74 to -77 feet below
msl. The trestle crossing will consist of two end bents and one
interior bent each consisting of three piles. The trolley bridge will
be constructed using precast concrete tee beams. The roadway approach
will consist of two bents supported by a total of 12 steel piles, with
a pre-cast prestressed slab bridge.
The 8th Street Bridge will consist of a total of 23 plumb piles.
Estimated pile depths range from 84 to -85 feet below msl. The trestle
crossing will consist of two end bents, one comprised of four piles and
the other composed of three piles, and one interior bent comprised of
four piles. The trolley bridge will be constructed using precast
concrete tee beams. The roadway approach will consist of two bents
supported by a total of 12 steel piles, with a pre-cast prestressed
slab bridge.
The 10th Street Bridge will consist of a total of 21 plumb piles.
Estimated pile depth is -64 feet below msl. The trestle crossing will
consist of two end bents and one interior bent each comprised of three
piles. The trolley bridge will be constructed using precast concrete
tee beams. The roadway approach will consist of two bents, each
constructed on six piles for a total of 12 piles, with a pre-cast
prestressed slab bridge.
Bridge Construction--The contractor will install a temporary 36-
inch casing at the site of each of the 65 permanent, 24-inch piles. The
temporary casings will be installed to a depth of approximately 7 feet
below the ground surface elevation using a vibratory hammer. The
permanent piles will be installed inside the casings, and will be
driven open-ended into very soft siltstone and mudstone to develop the
required axial resistance using a vibratory hammer followed by a diesel
impact hammer. It is estimated that the contractor will be able to
advance the permanent piles to roughly 80 percent of the desired depth
using the vibratory hammer, then will use the diesel hammer to seat the
piles at the desired depths.
Table 2--Pilings Expected To Be Removed and Installed at Each Bridge
----------------------------------------------------------------------------------------------------------------
36-inch temporary
Timber piles steel casings 24-inch steel
Bridge removed (each installed piles to be
and removed) installed
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6th Street Bridge............................................ 50 21 21
8th Street Bridge............................................ 50 23 23
10th Street Bridge........................................... 50 21 21
--------------------------------------------------
Total.................................................... 150 65 65
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[[Page 59777]]
The contractor has six temporary casings on-site, so they will need
to remove the casing once the permanent 24-inch piles are advanced to a
low enough depth with the vibratory hammer that the casing prohibits
driving the 24-inch pile with the diesel impact hammer. Removal of the
temporary casings will be completed using a vibratory hammer. The
removed pile will then be positioned elsewhere within the template to
guide additional pile installation. All bridge construction equipment
will be operated from the existing roadway and upland areas.
It is anticipated that the contractor may employ two crews during
construction. These crews would work concurrently at two different
bridge sites to keep the project on schedule. Implications for project
analysis and potential take are discussed in the Ensonified Area
section, below.
Abutment Wingwalls--Wingwalls will need to be constructed at the
10th Street crossing to help contain the roadway approach fill. The
wingwalls will be cast-in-place concrete retaining walls. Construction
of the wingwalls will require the operation of general construction
equipment (see Table 1 for source levels). The contractor will first
excavate existing ground to the desired elevation using an excavator
and dump truck positioned on the existing roadway. Then the contractor
will frame the wall using pneumatic tools or hammer and nails. Once
framed, concrete will be poured into the frame and allowed to cure. It
is anticipated that the contractor will be able to do this work in the
dry; however, the contractor will install isolation measures when
necessary. All equipment will be operated from the existing roadway and
upland areas.
Superstructures--The rail superstructures are comprised of precast,
prestressed slabs with a 2-inch wearing surface. Possible construction
equipment includes a crane, excavator, concrete saw, and concrete
mixer. Source levels are included in Table 1.
Roadway improvements will consist of curb and sidewalk
construction, asphalt paving, inlet construction, and utility
relocates. The roadway work will be completed using standard roadway
construction equipment, such as excavators and backhoes, dump trucks,
pavers, and rollers. Other equipment that may be employed includes air
compressors, jack hammers, concrete pumps and mixers, and pneumatic
tools. (See Table 1 for above-water equipment source levels). The work
will be conducted landward of the trolley crossings, will not require
IWW, and equipment will be operated away from the river. In-air noise
produced by roadway construction equipment will range from 78 dB RMS to
93 dB RMS at 20 meters from the source (Hanan & Associates, 2014).
Buildings and other above-grade structures will reduce noise during
roadway construction by physically blocking it and reflecting it away
from the river, due to structural noise reduction (FHWA, 2011). The
pier structures will also block noise from reaching the river and bank
areas by deflecting it upwards. Additionally, noise levels from much of
the construction equipment used for removal of the existing
superstructures are no different than many of the existing noise
sources in the area. Based on the sound levels produced by the proposed
equipment, existing site conditions, the likely location of the
pinnipeds within the area in relation to the associated construction
activities, and Phase 1 monitoring, roadway improvements are not
expected to disturb nearby marine mammals, and will not be considered
further.
Proposed mitigation, monitoring, and reporting measures are
described in detail later in this document (please see Proposed
Mitigation and Proposed Monitoring and Reporting).
Description of Marine Mammals in the Area of Specified Activities
Sections 3 and 4 of the application summarize available information
regarding status and trends, distribution and habitat preferences, and
behavior and life history, of the potentially affected species.
Additional information regarding population trends and threats may be
found in NMFS's Stock Assessment Reports (SARs; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and more general information about these species
(e.g., physical and behavioral descriptions) may be found on NMFS's
website (https://www.fisheries.noaa.gov/find-species).
Table 3 lists all species with expected potential for occurrence in
Astoria and summarizes information related to the population or stock,
including regulatory status under the MMPA and ESA and potential
biological removal (PBR), where known. For taxonomy, we follow
Committee on Taxonomy (2016). PBR is defined by the MMPA as the maximum
number of animals, not including natural mortalities, that may be
removed from a marine mammal stock while allowing that stock to reach
or maintain its optimum sustainable population (as described in NMFS's
SARs). While no mortality is anticipated or authorized here, PBR and
annual serious injury and mortality from anthropogenic sources are
included here as gross indicators of the status of the species and
other threats.
Marine mammal abundance estimates presented in this document
represent the total number of individuals that make up a given stock or
the total number estimated within a particular study or survey area.
NMFS's stock abundance estimates for most species represent the total
estimate of individuals within the geographic area, if known, that
comprises that stock. For some species, this geographic area may extend
beyond U.S. waters. For Steller sea lion (Eumetopias jubatus) the stock
abundance is the best estimate of pup and non-pup counts, which have
not been corrected to account for animals at sea during abundance
surveys. All managed stocks in this region are assessed in NMFS's U.S.
2018 SARs (e.g., Caretta et al. 2019). All values presented in Table 3
are the most recent available at the time of publication and are
available in the 2018 SARs (Caretta et al. 2019, Muto et al. 2019).
Table 3--Species With Expected Potential for Occurrence in Astoria
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Stock abundance
ESA/MMPA status; (CV, Nmin, most Annual M/SI 3
Common name Scientific name Stock Strategic (Y/N) 1 recent abundance PBR
survey) 2
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Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Balaenopteridae (rorquals)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Humpback whale................... Megaptera Central North -, -, Y 10,103 (0.300, 83 26
novaeangliae. Pacific. 7,891, 2006).
[[Page 59778]]
Humpback whale................... Megaptera California/Oregon/ -, -, Y 2,900 (0.05, 2,784, 16.7 =
novaeangliae. Washington. 2014). 40.2
--------------------------------------------------------------------------------------------------------------------------------------------------------
Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals and sea lions)
--------------------------------------------------------------------------------------------------------------------------------------------------------
California sea lion.............. Zalophus U.S................ -, -, N 257,606 (N/A, 14,011 >=321
californianus. 233,515, 2014).
Steller sea lion................. Eumetopias jubatus. Eastern U.S........ -, -, N 41,638 (See SAR, 2498 108
41,638, 2015).
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Phocidae (earless seals)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pacific harbor seal.............. Phoca vitulina Oregon/Washington -, -, N Unknown (Unknown, Undetermined 10.6
richardii. Coast. Unknown, 1999).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: www.nmfs.noaa.gov/pr/sars/. CV is coefficient of variation; Nmin is the minimum estimate of
stock abundance. In some cases, CV is not applicable [explain if this is the case].
\3\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV
associated with estimated mortality due to commercial fisheries is presented in some cases.
Note--Italicized species are not expected to be taken or proposed for authorization.
All species that could potentially occur in the proposed survey
areas are included in Table 3. However, the temporal and spatial
occurrence of humpback whales is such that take is not expected to
occur, and they are not discussed further beyond the explanation
provided here. Humpback whales occasionally enter the Columbia River to
feed (Calambokidis, et al., 2017), however their presence is rare. They
were not observed during Phase 1 of the City's project (OBEC Consulting
Engineers. 2019), and are not expected during Phase 2.
California sea lions
California sea lions are distributed throughout the Eastern North
Pacific from central Mexico to southeast Alaska, with breeding areas
restricted primarily to island areas off southern California (the
Channel Islands), Baja California, and in the Gulf of California
(Wright et al., 2010). There are five genetically distinct geographic
populations of California sea lions in U.S. waters (Schramm et al.,
2009). In Oregon, California sea lions are from the Pacific Temperate
population, and commonly occur in Oregon from September through May
(ODFW, 2015). The estimated net productivity rate for the species is 7
percent annually (Laake et al., 2018). Threats to this species include
incidental catch and entanglement in fishing gear, such as gillnets;
gunshot wounds and other human-caused injuries; entanglement in marine
debris; and oil exposure (Caretta et al., 2019).
Almost all California sea lions in the Pacific Northwest are sub-
adult or adult males (NMFS, 2008). California sea lions feed in the
Columbia River and adjacent nearshore marine areas, and have been
observed near several bridge crossings within the project site. They
are often seen swimming around underneath the existing structures, and
commonly use these areas when transiting from known temporary haul-outs
and foraging sites in the river channel. A small group haul out at the
Buoy Beer facility near the 8th Street bridge location. However, their
primary haulout in Astoria is the East Mooring Basin, which is located
over one mile (1.6km) upstream from the project site.
The bulk of the construction activities coincide with the season of
lowest California sea lion abundance in the Columbia River basin.
However, the in-water work period includes the tail end of peak usage
of the lower Columbia River by California sea lions. Additionally,
construction of the new rail superstructures will be partially above
the high mean tide elevation which is directly above the river banks
where California sea lions may be temporarily hauled-out.
Steller sea lions
The Steller sea lion range extends along the Pacific Rim, from
northern Japan to central California (Loughlin et al., 1984). Steller
sea lions inhabiting U.S. waters are divided into two stocks, the
Western U.S. stock and the Eastern U.S. stock. Steller sea lions that
occur within the Lower Columbia River are part of the Eastern U.S.
sock. The Eastern U.S. stock was de-listed in 2013 following a
population growth from 18,000 in 1979 to 70,000 in 2010 (and an
estimated annual growth of 4.18 percent) (NMFS, 2013). Threats to
Steller sea lions include: Boat/ship strikes, contaminants/pollutants,
habitat degradation, illegal hunting/shooting, offshore oil and gas
exploration, and interactions (direct and indirect) with fisheries
(NOAA, 2016b).
Steller sea lions are present year-round at the mouth of the
Columbia River, and they are at their peak in the lower river from
September through March. The primary haulout point is on the top of
South Jetty (ten miles downstream from the project site). At the South
Jetty, typical single day counts are approximately 100 individuals,
while at Phoca Rock/Bonneville Dam, there are approximately 40
individuals in a single day (Susan Riemer, pers. comm., 2016). Steller
sea lions feed in both the Columbia River and adjacent nearshore marine
areas. The timing of this
[[Page 59779]]
construction project coincides with peak presence of Steller sea lions
but they are not known to haul out near the project site. Steller sea
lions may be swimming past the project site in the main channel of the
river, however, no Steller sea lions were observed within the region of
activity during Phase 1 construction.
Harbor seals
On the U.S. west coast, Pacific harbor seals (Phoca vitulina
richardii) range from Alaska to Baja California, Mexico (ODFW, 2015).
Three separate harbor seal populations are recognized on the U.S. west
coast: California Stock, Washington Inland Waters Stock, and Oregon/
Washington Coast Stock (Caretta et al., 2019). In 1999, the Oregon/
Washington Coast stock abundance was estimated to be 24,732. However,
the data used to publish that abundance was eight years old at the time
and no more recent stock abundance estimates exist (Caretta et al.,
2019). The Oregon/Washington Coast stock of harbor seals is not listed
under the ESA nor are they considered depleted or strategic under the
MMPA.
Harbor seals utilize specific shoreline locations on a regular
basis as haulouts including beaches, rocks, floats, and buoys. They
must rest at haulout locations to regulate body temperature, interact
with one another, and sleep (NOAA, 2016a). Harbor seals are present
throughout the year at the mouth of the Columbia River and adjacent
nearshore marine areas. They are infrequently present at the Astoria
Mooring Basin, but they are known to transit through the main river
channel past the project site. Their closest haulout and pupping area
is Desdemona Sands which is downstream of the Astoria-Megler Bridge.
Pupping occurs from Mid-April to July, outside of the proposed project
work period (Susan Riemer, pers. comm., 2016). Due to their year-round
occurrence in the Columbia River, harbor seals are likely to be found
transiting the area during in-water construction.
Marine Mammal Hearing
Hearing is the most important sensory modality for marine mammals
underwater, and exposure to anthropogenic sound can have deleterious
effects. To appropriately assess the potential effects of exposure to
sound, it is necessary to understand the frequency ranges marine
mammals are able to hear. Current data indicate that not all marine
mammal species have equal hearing capabilities (e.g., Richardson et
al., 1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect
this, Southall et al. (2007) recommended that marine mammals be divided
into functional hearing groups based on directly measured or estimated
hearing ranges on the basis of available behavioral response data,
audiograms derived using auditory evoked potential techniques,
anatomical modeling, and other data. Note that no direct measurements
of hearing ability have been successfully completed for mysticetes
(i.e., low-frequency cetaceans). Subsequently, NMFS (2018) described
generalized hearing ranges for these marine mammal hearing groups.
Generalized hearing ranges were chosen based on the approximately 65
decibel (dB) threshold from the normalized composite audiograms, with
the exception for lower limits for low-frequency cetaceans where the
lower bound was deemed to be biologically implausible and the lower
bound from Southall et al. (2007) retained. Marine mammal hearing
groups and their associated hearing ranges are provided in Table 4.
Table 4--Marine Mammal Hearing Groups
[NMFS, 2018]
------------------------------------------------------------------------
Hearing group Generalized hearing range *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen 7 Hz to 35 kHz.
whales).
Mid-frequency (MF) cetaceans (dolphins, 150 Hz to 160 kHz.
toothed whales, beaked whales, bottlenose
whales).
High-frequency (HF) cetaceans (true 275 Hz to 160 kHz.
porpoises, Kogia, river dolphins,
cephalorhynchid, Lagenorhynchus cruciger
& L. australis).
Phocid pinnipeds (PW) (underwater) (true 50 Hz to 86 kHz.
seals).
Otariid pinnipeds (OW) (underwater) (sea 60 Hz to 39 kHz.
lions and fur seals).
------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a
composite (i.e., all species within the group), where individual
species' hearing ranges are typically not as broad. Generalized
hearing range chosen based on ~65 dB threshold from normalized
composite audiogram, with the exception for lower limits for LF
cetaceans (Southall et al. 2007) and PW pinniped (approximation).
The pinniped functional hearing group was modified from Southall et
al. (2007) on the basis of data indicating that phocid species have
consistently demonstrated an extended frequency range of hearing
compared to otariids, especially in the higher frequency range
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt,
2013).
For more detail concerning these groups and associated frequency
ranges, please see NMFS (2018) for a review of available information.
Three marine mammal species (all pinnipeds) have the reasonable
potential to co-occur with the proposed construction activities. Of
those pinniped species, two are otariids (Steller sea lion and
California sea lion) and one is a phocid (harbor seal). Please refer to
Table 3.
Potential Effects of Specified Activities on Marine Mammals and Their
Habitat
This section includes a summary and discussion of the ways that
components of the specified activity may impact marine mammals and
their habitat. The Estimated Take by Incidental Harassment section
later in this document includes a quantitative analysis of the number
of individuals that are expected to be taken by this activity. The
Negligible Impact Analysis and Determination section considers the
content of this section, the Estimated Take by Incidental Harassment
section, and the Proposed Mitigation section, to draw conclusions
regarding the likely impacts of these activities on the reproductive
success or survivorship of individuals and how those impacts on
individuals are likely to impact marine mammal species or stocks.
Description of Sound Sources
Sound travels in waves, the basic components of which are
frequency, wavelength, velocity, and amplitude. Frequency is the number
of pressure waves that pass by a reference point per unit of time and
is measured in hertz (Hz) or cycles per second. Wavelength is the
distance between two peaks of a sound wave; lower frequency sounds have
longer wavelengths than higher frequency sounds. Amplitude is the
[[Page 59780]]
height of the sound pressure wave or the `loudness' of a sound and is
typically measured using the decibel (dB) scale. A dB is the ratio
between a measured pressure (with sound) and a reference pressure
(sound at a constant pressure, established by scientific standards). It
is a logarithmic unit that accounts for large variations in amplitude;
therefore, relatively small changes in dB ratings correspond to large
changes in sound pressure. When referring to sound pressure levels
(SPLs; the sound force per unit area), sound is referenced in the
context of underwater sound pressure to 1 microPascal ([mu]Pa). One
Pascal is the pressure resulting from a force of one Newton exerted
over an area of one square meter. The source level (SL) represents the
sound level at a distance of 1 m from the source (referenced to 1
[mu]Pa). The received level is the sound level at the listener's
position. Note that all underwater sound levels in the document are
referenced to a pressure of 1 [mu]Pa and all airborne sound levels in
this document are referenced to a pressure of 20 [mu]Pa.
Root mean square (rms) is the quadratic mean sound pressure over
the duration of an impulse. Rms is calculated by squaring all of the
sound amplitudes, averaging the squares, and then taking the square
root of the average (Urick 1983). Rms accounts for both positive and
negative values; squaring the pressures makes all values positive so
that they may be accounted for in the summation of pressure levels
(Hastings and Popper, 2005). This measurement is often used in the
context of discussing behavioral effects, in part because behavioral
effects, which often result from auditory cues, may be better expressed
through averaged units than by peak pressures. When underwater objects
vibrate or activity occurs, sound-pressure waves are created. These
waves alternately compress and decompress the water as the sound wave
travels. Underwater sound waves radiate in all directions away from the
source (similar to ripples on the surface of a pond), except in cases
where the source is directional. The compressions and decompressions
associated with sound waves are detected as changes in pressure by
aquatic life and man-made sound receptors such as hydrophones.
Even in the absence of sound from the specified activity, the
underwater environment is typically loud due to ambient sound. Ambient
sound is defined as environmental background sound levels lacking a
single source or point (Richardson et al., 1995), and the sound level
of a region is defined by the total acoustical energy being generated
by known and unknown sources. These sources may include physical (e.g.,
waves, earthquakes, ice, atmospheric sound), biological (e.g., sounds
produced by marine mammals, fish, and invertebrates), and anthropogenic
sound (e.g., vessels, dredging, aircraft, construction).
A number of sources contribute to ambient sound, including the
following (Richardson et al., 1995):
Wind and waves: The complex interactions between wind and
water surface, including processes such as breaking waves and wave-
induced bubble oscillations and cavitation, are a main source of
naturally occurring ambient noise for frequencies between 200 Hz and 50
kilohertz (kHz) (Mitson, 1995). In general, ambient sound levels tend
to increase with increasing wind speed and wave height. Surf noise
becomes important near shore, with measurements collected at a distance
of 8.5 km from shore showing an increase of 10 dB in the 100 to 700 Hz
band during heavy surf conditions;
Precipitation: Sound from rain and hail impacting the
water surface can become an important component of total noise
frequencies above 500 Hz, and possibly down to 100 Hz during quiet
times;
Biological: Marine mammals can contribute significantly to
ambient noise levels, as can some fish and shrimp. The frequency band
for biological contributions is from approximately 12 Hz to over 100
kHz;
Anthropogenic: Sources of ambient noise related to human
activity include transportation (surface vessels and aircraft),
dredging and construction, oil and gas drilling and production, seismic
surveys, sonar, explosions, and ocean acoustic studies. Shipping noise
typically dominates the total ambient noise for frequencies between 20
and 300 Hz. In general, the frequencies of anthropogenic sounds are
below 1 kHz and, if higher frequency sound levels are created, they
attenuate rapidly (Richardson et al., 1995). Sound from identifiable
anthropogenic sources other than the activity of interest (e.g., a
passing vessel) is sometimes termed background sound, as opposed to
ambient sound.
The sum of the various natural and anthropogenic sound sources at
any given location and time--which comprise ``ambient'' or
``background'' sound--depends not only on the source levels (as
determined by current weather conditions and levels of biological and
shipping activity) but also on the ability of sound to propagate
through the environment. In turn, sound propagation is dependent on the
spatially and temporally varying properties of the water column and sea
floor, and is frequency-dependent. As a result of the dependence on a
large number of varying factors, ambient sound levels can be expected
to vary widely over both coarse and fine spatial and temporal scales.
Sound levels at a given frequency and location can vary by 10-20 dB
from day to day (Richardson et al., 1995). The result is that,
depending on the source type and its intensity, sound from the
specified activity may be a negligible addition to the local
environment or could form a distinctive signal that may affect marine
mammals.
In-water construction activities associated with the Project
include impact pile driving, vibratory pile removal and driving,
potential down-the-hole drilling (included in vibratory pile removal
and driving analysis), and potential preboring using an H-pile. The
sounds produced by these activities fall into one of two general sound
types: pulsed and non-pulsed (defined in the following). The
distinction between these two sound types is important because they
have differing potential to cause physical effects, particularly with
regard to hearing (e.g., Ward 1997 in Southall et al., 2007). Please
see Southall et al., (2007) for an in-depth discussion of these
concepts. Pulsed sound sources (e.g., impact pile driving) produce
signals that are brief (typically considered to be less than one
second), broadband, atonal transients (ANSI 1986; Harris 1998; NIOSH
1998; ISO 2003; ANSI 2005) and occur either as isolated events or
repeated in some succession. Pulsed sounds are all characterized by a
relatively rapid rise from ambient pressure to a maximal pressure value
followed by a rapid decay period that may include a period of
diminishing, oscillating maximal and minimal pressures, and generally
have an increased capacity to induce physical injury as compared with
sounds that lack these features. Non-pulsed sounds can be tonal,
narrowband or broadband, brief or prolonged, and may be continuous or
non-continuous (ANSI 1995; NIOSH 1998). Some of these non-pulsed sounds
can be transient signals of short duration without the essential
properties of pulses (e.g., rapid rise time). Examples of non-pulsed
sounds include those produced by vessels, aircraft, machinery
operations such as drilling or dredging, vibratory pile driving, and
active sonar systems (such as those used by the U.S. Navy). The
duration of such sounds, as received at a distance, can be greatly
extended in a highly reverberant environment. Impact
[[Page 59781]]
hammers operate by repeatedly dropping a heavy piston onto a pile to
drive the pile into the substrate.
Sound generated by impact hammers is characterized by rapid rise
times and high peak levels, a potentially injurious combination
(Hastings and Popper, 2005). Vibratory hammers install piles by
vibrating them and allowing the weight of the hammer to push them into
the sediment. Vibratory hammers produce significantly less sound than
impact hammers. Peak SPLs may be 180 dB or greater, but are generally
10 to 20 dB lower than SPLs generated during impact pile driving of the
same-sized pile (Oestman et al., 2009). Rise time is slower, reducing
the probability and severity of injury, and sound energy is distributed
over a greater amount of time (Nedwell and Edwards, 2002; Carlson et
al., 2005). Drilling would be conducted inside of the hollow 36-inch
casings. The pulsing sounds produced by the down-the-hole drilling
methods are continuous, however, this method likely increases sound
attenuation because the noise is primarily contained within the steel
pile and below ground, rather than impact hammer driving methods which
occur at the top of the pile (R&M, 2016).
The likely or possible impacts of the City's proposed activity on
marine mammals could involve both non-acoustic and acoustic stressors.
Potential non-acoustic stressors could result from the physical
presence of the equipment and personnel; however, any impacts to marine
mammals are expected to primarily be acoustic in nature. Acoustic
stressors include effects of heavy equipment operation during site
preparation and pile installation and removal, and use of above-water
construction equipment.
Acoustic Impacts
The introduction of anthropogenic noise into the aquatic
environment from pile driving and removal is the primary means by which
marine mammals may be harassed from the City's specified activity. In
general, animals exposed to natural or anthropogenic sound may
experience physical and psychological effects, ranging in magnitude
from none to severe (Southall et al., 2007). In general, exposure to
pile driving and drilling noise has the potential to result in auditory
threshold shifts and behavioral reactions (e.g., avoidance, temporary
cessation of foraging and vocalizing, changes in dive behavior).
Exposure to anthropogenic noise can also lead to non-observable
physiological responses such an increase in stress hormones. Additional
noise in a marine mammal's habitat can mask acoustic cues used by
marine mammals to carry out daily functions such as communication and
predator and prey detection. The effects of pile driving and drilling
noise on marine mammals are dependent on several factors, including,
but not limited to, sound type (e.g., impulsive vs. non-impulsive), the
species, age and sex class (e.g., adult male vs. mom with calf),
duration of exposure, the distance between the pile and the animal,
received levels, behavior at time of exposure, and previous history
with exposure (Wartzok et al., 2004; Southall et al., 2007). Here we
discuss physical auditory effects (threshold shifts) followed by
behavioral effects and potential impacts on habitat.
NMFS defines a noise-induced threshold shift (TS) as a change,
usually an increase, in the threshold of audibility at a specified
frequency or portion of an individual's hearing range above a
previously established reference level (NMFS, 2018). The amount of
threshold shift is customarily expressed in dB. A TS can be permanent
or temporary. As described in NMFS (2018), there are numerous factors
to consider when examining the consequence of TS, including, but not
limited to, the signal temporal pattern (e.g., impulsive or non-
impulsive), likelihood an individual would be exposed for a long enough
duration or to a high enough level to induce a TS, the magnitude of the
TS, time to recovery (seconds to minutes or hours to days), the
frequency range of the exposure (i.e., spectral content), the hearing
and vocalization frequency range of the exposed species relative to the
signal's frequency spectrum (i.e., how animal uses sound within the
frequency band of the signal (Kastelein et al., 2014)), and the overlap
between the animal and the source (e.g., spatial, temporal, and
spectral).
Permanent Threshold Shift (PTS)--NMFS defines PTS as a permanent,
irreversible increase in the threshold of audibility at a specified
frequency or portion of an individual's hearing range above a
previously established reference level (NMFS 2018). Available data from
humans and other terrestrial mammals indicate that a 40 dB threshold
shift approximates PTS onset (see Ward et al., 1958, 1959; Ward 1960;
Kryter et al., 1966; Miller, 1974; Ahroon et al., 1996; Henderson et
al., 2008). PTS levels for marine mammals are estimates, as with the
exception of a single study unintentionally inducing PTS in a harbor
seal (Kastak et al., 2008), there are no empirical data measuring PTS
in marine mammals largely due to the fact that, for various ethical
reasons, experiments involving anthropogenic noise exposure at levels
inducing PTS are not typically pursued or authorized (NMFS, 2018).
Temporary Threshold Shift (TTS)--A temporary, reversible increase
in the threshold of audibility at a specified frequency or portion of
an individual's hearing range above a previously established reference
level (NMFS, 2018). Based on data from cetacean TTS measurements (see
Southall et al., 2007), a TTS of 6 dB is considered the minimum
threshold shift clearly larger than any day-to-day or session-to-
session variation in a subject's normal hearing ability (Schlundt et
al., 2000; Finneran et al., 2000, 2002). As described in Finneran
(2015), marine mammal studies have shown the amount of TTS increases
with cumulative sound exposure level (SELcum) in an
accelerating fashion: At low exposures with lower SELcum,
the amount of TTS is typically small and the growth curves have shallow
slopes. At exposures with higher SELcum, the growth curves
become steeper and approach linear relationships with the noise SEL.
Depending on the degree (elevation of threshold in dB), duration
(i.e., recovery time), and frequency range of TTS, and the context in
which it is experienced, TTS can have effects on marine mammals ranging
from discountable to serious (similar to those discussed in auditory
masking, below). For example, a marine mammal may be able to readily
compensate for a brief, relatively small amount of TTS in a non-
critical frequency range that takes place during a time when the animal
is traveling through the open ocean, where ambient noise is lower and
there are not as many competing sounds present. Alternatively, a larger
amount and longer duration of TTS sustained during time when
communication is critical for successful mother/calf interactions could
have more serious impacts. We note that reduced hearing sensitivity as
a simple function of aging has been observed in marine mammals, as well
as humans and other taxa (Southall et al., 2007), so we can infer that
strategies exist for coping with this condition to some degree, though
likely not without cost.
Currently, TTS data only exist for four species of cetaceans
(bottlenose dolphin (Tursiops truncatus), beluga whale (Delphinapterus
leucas), harbor porpoise (Phocoena phocoena), and Yangtze finless
porpoise (Neophocoena asiaeorientalis)) and five species of pinnipeds
exposed to a limited number of sound sources (i.e., mostly tones and
octave-band noise) in laboratory settings
[[Page 59782]]
(Finneran, 2015). TTS was not observed in trained spotted (Phoca
largha) and ringed (Pusa hispida) seals exposed to impulsive noise at
levels matching previous predictions of TTS onset (Reichmuth et al.,
2016). In general, harbor seals and harbor porpoises have a lower TTS
onset than other measured pinniped or cetacean species (Finneran,
2015). Additionally, the existing marine mammal TTS data come from a
limited number of individuals within these species. No data are
available on noise-induced hearing loss for mysticetes. For summaries
of data on TTS in marine mammals or for further discussion of TTS onset
thresholds, please see Southall et al. (2007), Finneran and Jenkins
(2012), Finneran (2015), and Table 5 in NMFS (2018). Installing piles
requires a combination of impact pile driving and vibratory pile
driving. For the project, these activities would not occur at the same
time and there would likely be pauses in activities producing the sound
during each day. Given these pauses and that many marine mammals are
likely moving through the action area and not remaining for extended
periods of time, the potential for TS declines.
Behavioral Harassment--Exposure to noise from site preparation
activities and pile driving and removal also has the potential to
behaviorally disturb marine mammals. Available studies show wide
variation in response to underwater sound; therefore, it is difficult
to predict specifically how any given sound in a particular instance
might affect marine mammals perceiving the signal. If a marine mammal
does react briefly to an underwater sound by changing its behavior or
moving a small distance, the impacts of the change are unlikely to be
significant to the individual, let alone the stock or population.
However, if a sound source displaces marine mammals from an important
feeding or breeding area for a prolonged period, impacts on individuals
and populations could be significant (e.g., Lusseau and Bejder, 2007;
Weilgart, 2007; NRC, 2005).
Disturbance may result in changing durations of surfacing and
dives, number of blows per surfacing, or moving direction and/or speed;
reduced/increased vocal activities; changing/cessation of certain
behavioral activities (such as socializing or feeding); visible startle
response or aggressive behavior (such as tail/fluke slapping or jaw
clapping); avoidance of areas where sound sources are located.
Pinnipeds may increase their haul out time, possibly to avoid in-water
disturbance (Thorson and Reyff, 2006). Behavioral responses to sound
are highly variable and context-specific and any reactions depend on
numerous intrinsic and extrinsic factors (e.g., species, state of
maturity, experience, current activity, reproductive state, auditory
sensitivity, time of day), as well as the interplay between factors
(e.g., Richardson et al., 1995; Wartzok et al., 2003; Southall et al.,
2007; Weilgart, 2007; Archer et al., 2010). Behavioral reactions can
vary not only among individuals but also within an individual,
depending on previous experience with a sound source, context, and
numerous other factors (Ellison et al., 2012), and can vary depending
on characteristics associated with the sound source (e.g., whether it
is moving or stationary, number of sources, distance from the source).
In general, pinnipeds seem more tolerant of, or at least habituate more
quickly to, potentially disturbing underwater sound than do cetaceans,
and generally seem to be less responsive to exposure to industrial
sound than most cetaceans. Please see Appendices B-C of Southall et al.
(2007) for a review of studies involving marine mammal behavioral
responses to sound.
Disruption of feeding behavior can be difficult to correlate with
anthropogenic sound exposure, so it is usually inferred by observed
displacement from known foraging areas, the appearance of secondary
indicators (e.g., bubble nets or sediment plumes), or changes in dive
behavior. As for other types of behavioral response, the frequency,
duration, and temporal pattern of signal presentation, as well as
differences in species sensitivity, are likely contributing factors to
differences in response in any given circumstance (e.g., Croll et al.,
2001; Nowacek et al., 2004; Madsen et al., 2006; Yazvenko et al.,
2007). A determination of whether foraging disruptions incur fitness
consequences would require information on or estimates of the energetic
requirements of the affected individuals and the relationship between
prey availability, foraging effort and success, and the life history
stage of the animal.
During Phase 1 of the Astoria Waterfront Bridge Replacement
project, the City documented observations of marine mammals during
construction activities (i.e., pile driving and removal) at the bridge
sites (see 83 FR 19243 for Final IHA Federal Register notice). In the
marine mammal monitoring report, 604 California sea lions were observed
within the behavioral disturbance zone (4204 takes when extrapolated
across unobserved construction days) during pile driving activities
(i.e., documented as Level B harassment take). Behavioral reactions
were observed in only five percent of the observed California sea
lions, and included travel towards and away from construction
activities. 53 harbor seals were also observed within the behavioral
disturbance zone (323 takes when extrapolated across unobserved
construction days), however very few behavioral reactions were observed
by protected species observers (PSOs). Given that the projects sites in
Phase 2 are adjacent to those in Phase 1, and the fact the same species
are involved, we expect similar behavioral responses of marine mammals
to the specified activity. That is, disturbance, if any, is likely to
be temporary and localized (e.g., small area movements).
Masking--Sound can disrupt behavior through masking, or interfering
with, an animal's ability to detect, recognize, or discriminate between
acoustic signals of interest (e.g., those used for intraspecific
communication and social interactions, prey detection, predator
avoidance, navigation) (Richardson et al., 1995). Masking occurs when
the receipt of a sound is interfered with by another coincident sound
at similar frequencies and at similar or higher intensity, and may
occur whether the sound is natural (e.g., snapping shrimp, wind, waves,
precipitation) or anthropogenic (e.g., pile driving, shipping, sonar,
seismic exploration) in origin. The ability of a noise source to mask
biologically important sounds depends on the characteristics of both
the noise source and the signal of interest (e.g., signal-to-noise
ratio, temporal variability, direction), in relation to each other and
to an animal's hearing abilities (e.g., sensitivity, frequency range,
critical ratios, frequency discrimination, directional discrimination,
age or TTS hearing loss), and existing ambient noise and propagation
conditions. Masking of natural sounds can result when human activities
produce high levels of background sound at frequencies important to
marine mammals. Conversely, if the background level of underwater sound
is high (e.g., on a day with strong wind and high waves), an
anthropogenic sound source would not be detectable as far away as would
be possible under quieter conditions and would itself be masked. The
Lower Columbia River is used by various types of vessels, including
cargo ships, dredging vessels, fishing vessels, and pollution control
vessels, among others; therefore, background sound levels in the area
are sometimes already elevated.
Airborne Acoustic Effects--Pinnipeds that occur near the project
site could be exposed to airborne sounds associated
[[Page 59783]]
with pile driving and removal that have the potential to cause
behavioral harassment, depending on their distance from pile driving
activities. Cetaceans are not expected to be exposed to airborne sounds
that would result in harassment as defined under the MMPA.
Airborne noise is primarily an issue for pinnipeds that are
swimming or hauled out near the project site within the range of noise
levels exceeding the acoustic thresholds. We recognize that pinnipeds
in the water could be exposed to airborne sound that may result in
behavioral harassment when looking with their heads above water. Most
likely, airborne sound would cause behavioral responses similar to
those discussed above in relation to underwater sound. For instance,
anthropogenic sound could cause hauled-out pinnipeds to exhibit changes
in their normal behavior, such as reduction in vocalizations, or cause
them to temporarily abandon the area and move further from the source.
During in-water activities, these animals would previously have been
`taken' because of exposure to underwater sound above the behavioral
harassment thresholds, which are, in all cases, larger than those
associated with airborne sound. However, this project includes above-
water work that occurs near California sea lion haulouts, and there is
potential for above-water work to result in behavioral harassment of
these hauled out animals.
Marine Mammal Habitat Effects
The City's construction activities could have localized, temporary
impacts on marine mammal habitat by increasing in-water sound pressure
levels and slightly decreasing water quality. In-water construction
activities are of short duration and would likely have temporary
impacts on marine mammal habitat through increases in underwater sound
and minor visual disturbance due to the construction. Increased noise
levels may affect acoustic habitat (see masking discussion above) and
adversely affect marine mammal prey in the vicinity of the project area
(see discussion below). During impact pile driving and potential site
preparation activities, elevated levels of underwater noise would
ensonify the river where both fish and mammals may occur and could
affect foraging success.
In-water pile driving and pile removal would also cause short-term
effects on water quality due to increased turbidity. The City would
employ standard construction best management practices, thereby
reducing any impacts. Considering the nature and duration of the
effects, combined with the measures to reduce turbidity, the impact
from increased turbidity levels is expected to be discountable.
In-Water Construction Effects on Potential Foraging Habitat
The area likely impacted by the project is relatively small
compared to the available habitat in the surrounding waters of the
Columbia River and Pacific Ocean. Pile installation and removal may
temporarily increase turbidity resulting from suspended sediments. Any
increases would be temporary, localized, and minimal. In general,
turbidity associated with pile installation is localized to about a 25-
foot radius around the pile (Everitt et al., 1980). Based on monitoring
results from Phase 1, pinnipeds in the project area would likely be
traveling through and could avoid localized areas of turbidity.
Therefore, the impact from increased turbidity levels is expected to be
discountable to marine mammals. Furthermore, pile driving and removal
at the project site would not obstruct movements or migration of marine
mammals.
Avoidance by potential prey (i.e., fish) of the immediate area due
to the temporary loss of this foraging habitat is also possible. The
duration of fish avoidance of this area after pile driving stops is
unknown, but a rapid return to normal recruitment, distribution and
behavior is anticipated. Any behavioral avoidance by fish of the
disturbed area would still leave significantly large areas of fish and
marine mammal foraging habitat in the nearby vicinity. Impacts to
habitat and prey are expected to be temporary and minimal based on the
short duration of activities.
In-Water Construction Effects on Potential Prey (Fish)
Construction activities would produce continuous (i.e., vibratory
pile driving) and pulsed (i.e., impact driving) sounds. Fish react to
sounds that are especially strong and/or intermittent low-frequency
sounds. Short duration, sharp sounds can cause overt or subtle changes
in fish behavior and local distribution. Hastings and Popper (2005)
identified several studies that suggest fish may relocate to avoid
certain areas of sound energy. Additional studies have documented
effects of pile driving on fish, although several are based on studies
in support of large, multiyear bridge construction projects (e.g.,
Scholik and Yan, 2001, 2002; Popper and Hastings, 2009). Sound pulses
at received levels of 160 dB may cause subtle changes in fish behavior.
SPLs of 180 dB may cause noticeable changes in behavior (Pearson et
al., 1992; Skalski et al., 1992). SPLs of sufficient strength have been
known to cause injury to fish and fish mortality.
The most likely impact to fish from pile driving and drilling
activities at the project area would be temporary behavioral avoidance
of the area. The duration of fish avoidance of this area after pile
driving stops is unknown, but a rapid return to normal recruitment,
distribution and behavior is anticipated. In general, impacts to marine
mammal prey species are expected to be minor and temporary due to the
short timeframe for the project. Uncertainty regarding direct and
indirect effects on prey species will be mitigated due to the seasonal
presence of salmonids and other prey present in the area, and the
mitigation measures in place to reduce impacts to fish under Federal
Aid Highway Program (FAHP). Further, it is anticipated that some of the
pile driving activities will occur in the dry, despite the conservative
project analysis that assumes all pile driving would occur in-water.
Sound attenuation devices will be installed for in-water pile driving.
Construction activities, in the form of increased turbidity, have
the potential to adversely affect fish in the project area. Increased
turbidity is expected to occur in the immediate vicinity (on the order
of 10 feet or less) of construction activities. However, suspended
sediments and particulates are expected to dissipate quickly within a
single tidal cycle. Given the limited area affected and high tidal
dilution rates, any effects on fish are expected to be minor or
negligible. In addition, best management practices would be in effect,
which would limit the extent of turbidity to the immediate project
area.
In summary, given the large areas of fish and marine mammal
foraging habitat in the Columbia River outside of the ensonified area,
and the anticipated rapid return to the project area following
cessation of in-water work, pile driving and site preparation
activities associated with the proposed action are not likely to have a
permanent, adverse effect on any fish habitat, or populations of fish
species. Thus, we conclude that impacts of the specified activity are
not likely to have more than short-term adverse effects on any prey
habitat or populations of prey species. Further, any impacts to marine
mammal habitat are not expected to result in significant or long-term
consequences for individual marine mammals, or to contribute to adverse
impacts on their populations.
[[Page 59784]]
Estimated Take
This section provides an estimate of the number of incidental takes
proposed for authorization through this IHA, which will inform both
NMFS' consideration of ``small numbers'' and the negligible impact
determination.
Harassment is the only type of take expected to result from these
activities. Except with respect to certain activities not pertinent
here, section 3(18) of the MMPA defines ``harassment'' as any act of
pursuit, torment, or annoyance, which (i) has the potential to injure a
marine mammal or marine mammal stock in the wild (Level A harassment);
or (ii) has the potential to disturb a marine mammal or marine mammal
stock in the wild by causing disruption of behavioral patterns,
including, but not limited to, migration, breathing, nursing, breeding,
feeding, or sheltering (Level B harassment).
Authorized takes would primarily be by Level B harassment, as use
of the vibratory and impact pile hammers, potential drill, and other
construction equipment has the potential to result in disruption of
behavioral patterns for individual marine mammals. There is also some
potential for auditory injury (Level A harassment) to California sea
lions and harbor seals because they are more likely to occur closer to
the project site, particularly considering the small, nearby California
sea lion haulout. Auditory injury is unlikely to occur to other groups,
and the proposed mitigation and monitoring measures are expected to
minimize the severity of such taking to the extent practicable.
As described previously, no mortality or serious injury is
anticipated or proposed to be authorized for this activity. Below we
describe how the take is estimated.
Generally speaking, we estimate take by considering: (1) Acoustic
thresholds above which NMFS believes the best available science
indicates marine mammals will be behaviorally harassed or incur some
degree of permanent hearing impairment; (2) the area or volume of water
that will be ensonified above these levels in a day; (3) the density or
occurrence of marine mammals within these ensonified areas; and, (4)
and the number of days of activities. We note that while these basic
factors can contribute to a basic calculation to provide an initial
prediction of takes, additional information that can qualitatively
inform take estimates is also sometimes available (e.g., previous
monitoring results or average group size). Below, we describe the
factors considered here in more detail and present the proposed take
estimate.
Acoustic Thresholds
Using the best available science, NMFS has developed acoustic
thresholds that identify the received level of underwater sound above
which exposed marine mammals would be reasonably expected to be
behaviorally harassed (equated to Level B harassment) or to incur PTS
of some degree (equated to Level A harassment). Thresholds have also
been developed identifying the received level of in-air sound above
which exposed pinnipeds would likely be behaviorally harassed.
Level B Harassment for non-explosive sources--Though significantly
driven by received level, the onset of behavioral disturbance from
anthropogenic noise exposure is also informed to varying degrees by
other factors related to the source (e.g., frequency, predictability,
duty cycle), the environment (e.g., bathymetry), and the receiving
animals (hearing, motivation, experience, demography, behavioral
context) and can be difficult to predict (Southall et al., 2007;
Ellison et al., 2012). Based on what the available science indicates
and the practical need to use a threshold based on a factor that is
both predictable and measurable for most activities, NMFS uses a
generalized acoustic threshold based on received level to estimate the
onset of behavioral harassment. NMFS predicts that marine mammals are
likely to be behaviorally harassed in a manner we consider Level B
harassment when exposed to underwater anthropogenic noise above
received levels of 120 dB re 1 [mu]Pa (rms) for continuous (e.g.,
vibratory pile-driving, drilling) and above 160 dB re 1 [mu]Pa (rms)
for non-explosive impulsive (e.g., seismic airguns) or intermittent
(e.g., scientific sonar) sources. For in-air sounds, NMFS predicts that
harbor seals exposed above received levels of 90 dB re 20 [mu]Pa (rms)
will be behaviorally harassed, and other pinnipeds will be harassed
when exposed above 100 dB re 20 [mu]Pa (rms).
The City's proposed activity includes the use of continuous
(vibratory pile driving, preboring and potential down-the-hole
drilling) and impulsive (impact pile driving) sources, and therefore
the 120 and 160 dB re 1 [mu]Pa (rms) are applicable for in-water noise.
Level A harassment for non-explosive sources--NMFS' Technical
Guidance for Assessing the Effects of Anthropogenic Sound on Marine
Mammal Hearing (Version 2.0) (Technical Guidance, 2018) identifies dual
criteria to assess auditory injury (Level A harassment) to five
different marine mammal groups (based on hearing sensitivity) as a
result of exposure to noise from two different types of sources
(impulsive or non-impulsive). The City's proposed activities include
the use of impulsive (impact hammers) and non-impulsive (vibratory
hammers, potential down-the-hole drilling) sources.
These thresholds are provided in the table below. The references,
analysis, and methodology used in the development of the thresholds are
described in NMFS 2018 Technical Guidance, which may be accessed at
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.
Table 5--Thresholds Identifying the Onset of Permanent Threshold Shift
------------------------------------------------------------------------
PTS onset acoustic thresholds *
(received level)
Hearing group ------------------------------------------
Impulsive Non-impulsive
------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans. Cell 1: Cell 2: LE,LF,24h: 199
Lpk,flat: 219 dB
dB; LE,LF,24h:
183 dB..
Mid-Frequency (MF) Cetaceans. Cell 3: Cell 4: LE,MF,24h: 198
Lpk,flat: 230 dB.
dB; LE,MF,24h:
185 dB.
High-Frequency (HF) Cetaceans Cell 5: Cell 6: LE,HF,24h: 173
Lpk,flat: 202 dB.
dB; LE,HF,24h:
155 dB.
Phocid Pinnipeds (PW) Cell 7: Cell 8: LE,PW,24h: 201
(Underwater). Lpk,flat: 218 dB.
dB; LE,PW,24h:
185 dB.
[[Page 59785]]
Otariid Pinnipeds (OW) Cell 9: Cell 10: LE,OW,24h: 219
(Underwater). Lpk,flat: 232 dB.
dB; LE,OW,24h:
203 dB.
------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever
results in the largest isopleth for calculating PTS onset. If a non-
impulsive sound has the potential of exceeding the peak sound pressure
level thresholds associated with impulsive sounds, these thresholds
should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [mu]Pa, and
cumulative sound exposure level (LE) has a reference value of
1[mu]Pa\2\s. In this Table, thresholds are abbreviated to reflect
American National Standards Institute standards (ANSI 2013). However,
peak sound pressure is defined by ANSI as incorporating frequency
weighting, which is not the intent for this Technical Guidance. Hence,
the subscript ``flat'' is being included to indicate peak sound
pressure should be flat weighted or unweighted within the generalized
hearing range. The subscript associated with cumulative sound exposure
level thresholds indicates the designated marine mammal auditory
weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds)
and that the recommended accumulation period is 24 hours. The
cumulative sound exposure level thresholds could be exceeded in a
multitude of ways (i.e., varying exposure levels and durations, duty
cycle). When possible, it is valuable for action proponents to
indicate the conditions under which these acoustic thresholds will be
exceeded.
Ensonified Area
Here, we describe operational and environmental parameters of the
activity that will feed into identifying the area ensonified above the
acoustic thresholds, which include source levels and transmission loss
coefficient.
The sound field in the project area is the existing background
noise plus additional construction noise from the proposed project.
Marine mammals are expected to be affected via sound generated by the
primary components of the project (i.e., impact pile driving, vibratory
pile driving and removal, site preparation). The maximum (underwater)
area ensonified above the thresholds for behavioral harassment
referenced above is 21.53km (13.38 mi) into the river channel during
vibratory installation/removal of the 36-inch temporary steel casings,
though this distance does not account for tide levels. There is a
chance that pile installation work could be done during low tides,
where exposed sand bars could significantly reduce the Level B ZOI.
The project includes vibratory removal of timber piles, vibratory
and impact pile installation of steel pipe piles and site preparation
using a vibratory hammer and H-pile. Source levels of pile
installation/removal activities and site preparation are based on
reviews of measurements of the same or similar types and dimensions of
piles available in the literature. Source levels for each pile size and
driving method are presented in Table 6. Source levels for vibratory
installation and removal of piles of the same diameter are assumed to
be the same.
The source level for vibratory removal of timber piles is from in-
water measurements generated by the Greenbusch Group (2018) from the
Seattle Pier 62 project (83 FR 39709; April 10, 2018). Hydroacoustic
monitoring results from Pier 62 determined unweighted rms ranging from
140 dB to 169 dB. NMFS analyzed source measurements at different
distances for all 63 individual timber piles that were removed at Pier
62 and normalized the values to 10 m. The results showed that the
median is 152 dB SPLrms.
Table 6--Sound Source Levels for In-Water Activities
----------------------------------------------------------------------------------------------------------------
Source level (at 10m)
Pile size/type Method ------------------------------------------------ Literature
dB RMS dB SEL \b\ dB peak source
----------------------------------------------------------------------------------------------------------------
14-inch Timber............... Vibratory....... 152 .............. .............. The Greenbusch
Group, Inc
(2018).
14-inch Steel H-pile......... Vibratory....... 150 .............. .............. WSDOT (2016).
24-inch Steel Pipe........... Vibratory....... 162 .............. .............. WSDOT (2010).
Impact.......... \a\ 187 \a\ 171 \a\ 200 WSDOT (2016).
36-inch Steel Pipe........... Vibratory....... 170 .............. .............. CA Dept. of
Transportation
(2015).
----------------------------------------------------------------------------------------------------------------
\a\ Includes 7dB reduction from use of bubble curtain.
\b\ Sound exposure level (dB re 1 [mu]Pa\2\-sec).
It is anticipated that the contractor may employ two crews during
construction to keep the project on schedule. This could result in
concurrent use of a vibratory hammer and an impact hammer, however, the
contractor will not operate two of the same hammer type concurrently.
The hammers would be operated at two different bridges. The ensonified
zones would likely overlap during concurrent use, but the multiple-
source decibel addition method (Table 7) does not result in significant
increases in the noise source when an impact hammer and vibratory
hammer are operated at the same time, because the difference in noise
source levels (Table 6) between the two hammers is greater than 10dB.
Table 7--Multiple-Source Decibel Addition
------------------------------------------------------------------------
Add the
following to
When two decibel values differ by: the higher
level
------------------------------------------------------------------------
0-1 dB.................................................. 3 dB
2-3 dB.................................................. 2 dB
4-9 dB.................................................. 1 dB
>10 dB.................................................. 0 dB
------------------------------------------------------------------------
[[Page 59786]]
Transmission loss (TL) is the decrease in acoustic intensity as an
acoustic pressure wave propagates out from a source. TL parameters vary
with frequency, temperature, sea conditions, current, source and
receiver depth, water depth, water chemistry, and bottom composition
and topography. The general formula for underwater TL is:
TL = B * Log10 (R 1/R 2),
where
TL = transmission loss in dB
B = transmission loss coefficient
R 1 = the distance of the modeled SPL from the driven
pile, and
R 2 = the distance from the driven pile of the initial
measurement
Absent site-specific acoustical monitoring with differing measured
transmission loss, a practical spreading value of 15 is used as the
transmission loss coefficient in the above formula. Site-specific
transmission loss data for Astoria are not available, therefore the
default coefficient of 15 is used to determine the distances to the
Level A and Level B harassment thresholds.
Table 8--In-Water Activity Source Levels and Distances to Level B Harassment Thresholds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source level Level B Level B
at 10 m (dB re threshold (dB Propagation Distance to harassment
Pile size/type Method 1 [micro]Pa re 1 [micro]Pa (xLogR) Level B ensonified
rms) rms) threshold (m) area (km\2\)
--------------------------------------------------------------------------------------------------------------------------------------------------------
14-inch Timber............................ Vibratory................... 152 120 15 1,359.4 3.2
14-inch Steel H-pile...................... Vibratory................... 150 120 15 1,000.0 1.8
24-inch Steel Pipe........................ Vibratory................... 162 120 15 6,309.6 55.3
Impact...................... 187 160 15 631.0 0.8
36-inch Steel Pipe........................ Vibratory................... 170 120 15 21,544.4 212.3
--------------------------------------------------------------------------------------------------------------------------------------------------------
In-Air Disturbance during General Construction Activities--
Behavioral disturbance (Level B harassment take) may occur incidental
to the use of construction equipment during general construction that
is proposed in the dry, above water, or inland within close proximity
to the river banks. These construction activities are associated with
the removal and construction of the rail superstructures, removal of
the existing concrete foundations, construction of abutment wingwalls,
and the construction of a temporary work platform. Possible equipment
and sound source levels are included in Table 1. Using the Spherical
Spreading Loss Model (20logR), a maximum sound source level of 93 dB
RMS at 20 m, sound levels in-air would attenuate below the 90dB RMS
Level B harassment threshold for harbor seals at 28 m, and below the
100 dB RMS threshold for all other pinnipeds at 9 m. Harbor seals are
not expected to occur within 28m of the activity as there are no nearby
haulouts, and are, therefore, not expected to be harassed by in-air
sound. Additionally, the City is proposing a 10 m shutdown zone (Table
16) for all construction work to prevent injury from physical
interaction with equipment. The City would therefore shut down
equipment before hauled out sea lions could be acoustically harassed by
the sound produced. No Level B harassment is expected to occur due to
increased sounds from roadway construction. However, sea lions may be
disturbed by the presence of construction equipment and increased human
presence during above-water construction.
When the NMFS Technical Guidance (2016) was published, in
recognition of the fact that ensonified area/volume could be more
technically challenging to predict because of the duration component in
the new thresholds, we developed a User Spreadsheet that includes tools
to help predict a simple isopleth that can be used in conjunction with
marine mammal density or occurrence to help predict takes. We note that
because of some of the assumptions included in the methods used for
these tools, we anticipate that isopleths produced are typically going
to be overestimates of some degree, which may result in some degree of
overestimate of Level A harassment take. However, these tools offer the
best way to predict appropriate isopleths when more sophisticated 3D
modeling methods are not available, and NMFS continues to develop ways
to quantitatively refine these tools, and will qualitatively address
the output where appropriate. For stationary sources such as pile
driving, NMFS User Spreadsheet predicts the distance at which, if a
marine mammal remained at that distance the whole duration of the
activity, it would incur PTS. Inputs entered in the User Spreadsheet
(Table 9) and the resulting isopleths are reported below (Table 10).
Table 9--User Spreadsheet Input Parameters Used for Calculating Level A Harassment Isopleths
--------------------------------------------------------------------------------------------------------------------------------------------------------
Weighting Number of Duration to Distance from
Pile size and installation Spreadsheet tab factor Source level at piles drive Number of Propagation source level
method used adjustment 10 m within 24-h single pile strikes per (xLogR) measurement
(kHz) period (minutes) pile (meters)
--------------------------------------------------------------------------------------------------------------------------------------------------------
14-inch Timber Vibratory....... A.1) Vibratory 2.5 152dB RMS SPL.... 50 20 ........... 15 10
pile driving.
14-inch Steel H-Pile........... A.1) Vibratory 2.5 150dB RMS SPL.... 36 25 ........... 15 10
pile driving.
24-inch Steel Vibratory........ A.1) Vibratory 2.5 162dB RMS SPL.... 18 20 ........... 15 10
pile driving.
36-inch Steel Vibratory........ A.1) Vibratory 2.5 170dB RMS SPL.... 36 8 ........... 15 10
pile driving.
24-inch Steel Impact........... E.1) Impact pile 2 171dB SEL/207 PK 23 ........... 500 15 10
driving. SPL.
--------------------------------------------------------------------------------------------------------------------------------------------------------
[[Page 59787]]
The applicant may conduct down-the-hole drilling, however a
separate analysis is not provided for that activity, as it is was not
necessary in Phase 1 of the project, and is not expected to be
necessary in Phase 2. Should drilling be necessary, the Level B
harassment zone will be considered to be the same as that calculated
for vibratory installation/removal of 36-inch steel piles, as that
Level B harassment zone is clipped in all directions, and therefore is
the most conservative a Level B harassment zone could be. A
conservative Level B harassment zone is of particular importance due to
the fact that the duration of drilling, should it be necessary, is
unknown. The applicant will consider the Level A harassment zone for
down-the-hole drilling to be the same as the Level A harassment zones
calculated for impact pile driving of the 24-inch steel piles. These
are the largest Level A harassment zones, and Level A harassment zones
are expected to be smaller for a continuous sound source such as down-
the-hole drilling.
Table 10--Calculated Distances to Level A Harassment Isopleths
------------------------------------------------------------------------
Level A harassment zone (m)
Pile size and installation method -------------------------------
Phocids Otariids
------------------------------------------------------------------------
14-inch Timber Vibratory................ 6.8 0.5
14-inch Steel H-Pile.................... 4.7 0.3
24-inch Steel Vibratory................. 16 1.1
36-inch Steel Vibratory................. 47 3.3
24-inch Steel Impact (and down-the-hole * 431.5 31.4
drilling, if necessary)................
------------------------------------------------------------------------
* (Peak 7.4)
Marine Mammal Occurrence and Take Calculation and Estimation
In this section we provide the information about the presence,
density, or group dynamics of marine mammals, and how it is brought
together with the information provided above to produce a quantitative
take estimate. Estimated takes of each species were calculated using
information provided by the Oregon Department of Fish and Wildlife
(Bryan Wright, pers. comm., August 2019), Washington Department of Fish
and Wildlife (WDFW, 2014) and the Marine Mammal Commission (Tiff
Brookens, pers. comm., March 2018).
Harbor Seal
Numbers of harbor seals hauled out at Desdemona Sands have been
reported to reach into the thousands (Profita, 2015), but specific
counts were unavailable. Without counts of harbor seals closer to the
project site, the maximum average count of harbor seals at the South
Jetty (57 seals; WDFW, 2014) is used to calculate take, as in Phase 1
(83 FR 19243, May 2, 2018). The Level B harassment zones for Phase 2
extend far beyond the calculated zones for Phase 1, approaching the
South Jetty, further supporting the use of these harbor seal counts.
Harbor seals do not haul out near the project area and would only
be potentially harassed if they are transiting through the Level A or
Level B harassment zone during the in-water work period (including the
extension, if applicable). Level B harassment take was calculated by
multiplying the maximum average count of harbor seals at the South
Jetty by days of in-water activity (Table 11).
Additionally, while harbor seals are unlikely to occur in the Level
A harassment zone during vibratory pile driving (based on Phase 1
monitoring), the applicant is concerned that if a few animals occurred
in the Level A harassment zone during impact pile driving, they may
need to shut down more frequently than is practical, given the IWWP
restrictions previously discussed. As such, NMFS is proposing to
observe a shutdown zone that is smaller than the Level A isopleth for
impact pile driving and to issue small numbers of Level A harassment
take of harbor seals (Table 14). This proposed take would avoid
potentially excessive shut downs should a small group of harbor seals
enter the project area on each day while impact pile driving activities
(or down-the-hole drilling, as necessary) are underway. Level A
harassment take of harbor seals was calculated by multiplying a group
of two animals by 14 in-water work days. Level A takes may only occur
during the subset of in-water work days when the applicant conducts
impact pile driving (or down-the-hole drilling, as required), as the
shutdown zone contains the entire Level A harassment zone for all other
in-water work activities.
Steller Sea Lion
Counts of Steller sea lions at the East Mooring Basin are typically
in the single digits (B. Wright, pers. comm., March 2018), while the
average number of Steller sea lions observed at the South Jetty during
the in-water work period (including the possible extension) from 2000-
2014, was 272 animals (WDFW, 2014). When the applicant consulted ODFW
for more recent Steller sea lion data, ODFW advised that there were
only three more recent surveys, none of which occurred during the IWWP
months (Bryan Wright, pers. comm., September 2019). The Level B
harassment zones for Phase 2 extend far beyond the calculated zones for
Phase 1, approaching the South Jetty. Therefore, NMFS expects that that
average daily count from the South Jetty provides an appropriate daily
count to calculate potential Steller sea lion Level B harassment take
during Phase 2. Note the calculation is based on the average daily
count, not the maximum. The maximum daily count was 606 animals, in the
month of April. Considering that work will only occur in April if the
entire IWWP extension is exercised, and the large difference between
the maximum daily count and the average daily count, NMFS believes that
using the maximum daily count would greatly overestimate potential
take.
For Phase 1 Level B harassment take calculations of Steller sea
lions, daily estimates were based off of observations at Bonneville Dam
and Willamette Falls, as these animals must transit past Astoria at
some point in their travels from the Pacific to the upper Columbia
River (83 FR 19243, May 2, 2018). The daily count was 67 animals, 63 at
Bonneville Dam and four at Willamette Falls. However, NMFS believes
that South Jetty estimates are more appropriate and more conservative
for Phase 2 take calculations, given the larger Level B harassment
zones, some of which extend downriver close to the South Jetty.
Level B harassment take was calculated by multiplying the daily
counts of Steller sea lions by days of activity (Table 11).
[[Page 59788]]
Steller sea lions do not haul out near the construction sites and
would only be potentially harassed if they are transiting through the
Level B harassment zone during the in-water work period (including the
extension, if applicable). Steller sea lions are not expected to occur
within the calculated Level A harassment zone for otariids (Table 10).
No Level A harassment takes of Steller sea lions are proposed nor
expected to be authorized.
Table 11--Level B Harassment Take Calculation for Harbor Seal and Steller Sea Lion
----------------------------------------------------------------------------------------------------------------
Maximum Days of in-
Species average/daily water activity Total take
count \c\ (Level B)
----------------------------------------------------------------------------------------------------------------
Harbor seal..................................................... \a\ 57 21 1,197
Steller sea lion................................................ \b\ 272 21 5,712
----------------------------------------------------------------------------------------------------------------
\a\ Maximum average count of harbor seals at the South Jetty (WDFW, 2014).
\b\ Average number of Steller sea lions observed at the South Jetty during the in-water work period (including
the possible extension) from 2000-2014 (WDFW, 2014).
\c\ Includes in-water activity for the entire project.
California Sea Lion
Aerial surveys of the East Mooring Basin in Astoria from 2011 to
2018 (Bryan Wright, pers. comm., August 2019) were used to calculate
in-water Level B harassment take of California sea lions, as in Phase 1
of this activity (83 FR 19243, May 2, 2018). The data provided to NMFS
by ODFW included the maximum California sea lion count observed on a
single day for each month throughout the survey period. These maximum
counts at the East Mooring Basin ranged from 0 California sea lions on
a single day in July 2017 to 3,834 on a single day in March 2016. A
``daily average maximum'' for each IWWP month (Table 12) was calculated
by averaging the maximum counts on a single day for each survey month
provided by ODFW. In addition to ODFW aerial surveys, the City
conducted opportunistic surveys of pinnipeds at the bridge sites in
December 2017. A maximum of four California sea lions were observed in
the water surrounding the bridges and piers. Additional California sea
lions were heard vocalizing from the riverbanks under the bridges but
the exact number of sea lions could not be determined.
Table 12--Daily Average Maximum Number of California Sea Lions at East
Mooring Basin for IWWP Months, Including the Potential Extension
------------------------------------------------------------------------
Daily average
Month maximum \a\
------------------------------------------------------------------------
November................................................ 141
December................................................ 135
January................................................. 408
February................................................ 893
March................................................... 1,191
April................................................... 982
------------------------------------------------------------------------
\a\ Daily average maximum was calculated using data from aerial surveys
of the East Mooring Basin in Astoria from 2011 to 2018 (Bryan Wright,
pers. comm., 2019).
California sea lions are the most commonly observed marine mammal
in the area, and are known to haul out on the riverbanks and structures
near the bridges, as described above. California sea lions may be
harassed by underwater sound resulting from vibratory pile removal and
impact pile driving (at the distances listed above) as well as airborne
sound resulting from roadway and railway demolition and construction.
As such, California sea lions may be subject to harassment throughout
the duration of Phase 2 of the project (December through November).
NMFS is proposing to authorize 1,056 Level B harassment takes of
California sea lions associated with above-water construction
activities taking place during the above-water work period, not
including the IWWP extension (May to October). Level B harassment takes
of California sea lions from above-water activities were calculated by
multiplying the maximum estimate from the City's 2017 opportunistic
surveys at the bridge sites (16 animals) by the estimated 11 days of
work per month during the above-water work period.
NMFS is proposing to authorize 25,011 Level B harassment takes of
California sea lions associated with in-water and above-water work
during the IWWP. The City expects approximately 21 in-water work days
across Phase 2 of the project. However, because the exact construction
schedule is unknown, there are uncertainties in how many of the
estimated work days will occur during each month. Therefore, estimated
Level B harassment take during the IWWP (Table 13) is calculated by
multiplying the highest daily average maximum (Table 12) during the
IWWP months (including the potential extension) by the estimated 21 in-
water work days. California sea lions exposed to in-air sound above
Level B harassment threshold during the IWWP are expected to have
already been taken by in-water activity, and therefore already be
included in the take calculation.
Total California sea lion Level B harassment takes (Table 13) are
calculated as the sum of above-water work period and IWWP takes.
Table 13--Level B Harassment Take Calculation of California Sea Lion
----------------------------------------------------------------------------------------------------------------
Potential
Work period Daily average number of Takes per
maximum \b\ workdays month
----------------------------------------------------------------------------------------------------------------
IWWP \a\........................................................ 1,191 21 25,011
May............................................................. 16 11 176
June............................................................ 16 11 176
July............................................................ 16 11 176
August.......................................................... 16 11 176
September....................................................... 16 11 176
[[Page 59789]]
October......................................................... 16 11 176
-----------------------------------------------
Total....................................................... .............. .............. 26,067
----------------------------------------------------------------------------------------------------------------
\a\ IWWP includes the potential extension, as the month of March has the highest daily average maximum count.
\b\ Daily average maximums during above-water work months are estimates from the City's opportunistic surveys at
the Phase 1 bridge sites in December 2017.
Only 4204 Level B harassment takes of California sea lion were
reported for Phase 1; however, the Phase 2 project area is much larger
than the area within which marine mammals were reported in Phase 1.
Therefore, NMFS expects California sea lion take to be higher for Phase
2 than was reported in the monitoring report for Phase 1.
As discussed above, the City estimates that approximately 16
California sea lions haul out near the project sites based on
opportunistic surveys conducted in December 2017. Frequent construction
shutdowns are of concern to the applicant, as there is a limited IWWP
imposed by the Oregon Department of Fish and Wildlife and, therefore,
the proposed mitigation zone does not entirely contain the area within
the Level A harassment isopleth for impact pile driving. The applicant
has requested Level A harassment takes of California sea lions, as the
animals that haulout nearby may enter the Level A harassment zone as
they transit between the haulouts and their feeding areas in the
Columbia River.
NMFS is proposing to issue 224 Level A harassment takes of
California sea lions (Table 14). The Level A harassment takes are
calculated by multiplying the 16 animals that haulout near the project
site (City of Astoria December 2017 surveys) by 14 in-water work days.
Level A takes may only occur during the subset of in-water work days
when the applicant conducts impact pile driving (or down-the-hole
drilling, as required), as the shutdown zone contains the entire Level
A harassment zone for all other in-water work activities.
Table 14--Level A Harassment Take Calculation of Harbor Seal and California Sea Lion
----------------------------------------------------------------------------------------------------------------
Estimated
number of in- Level A
Species Daily count water work harassment
days take
----------------------------------------------------------------------------------------------------------------
Harbor seal..................................................... 2 14 28
California sea lion............................................. \a\ 16 14 224
----------------------------------------------------------------------------------------------------------------
\a\ December 2017 survey estimates of California sea lions by the City at Phase 1 bridge sites.
Table 15--Total Level A and Level B Take Proposed for Authorization
--------------------------------------------------------------------------------------------------------------------------------------------------------
Level A Level B
Common name Stock harassment harassment Total take Stock Percent of
take take abundance stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor seal............................... Oregon/Washington Coast..... 28 1,197 1,225 \a\ 24,732 5.0
Steller sea lion.......................... Eastern U.S................. 0 5,712 5,712 41,638 13.7
California sea lion....................... U.S......................... 224 26,067 26,291 257,606 10.2
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ As noted in Table 3, there is no current estimate of abundance available for the Oregon/Washington Coast stock of harbor seal. The abundance
estimate from 1999, included here, is the most recent.
Proposed 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 (latter not applicable for this action). NMFS
regulations require applicants for incidental take authorizations to
include information about the availability and feasibility (economic
and technological) of equipment, methods, and manner of conducting such
activity or other means of effecting the least practicable adverse
impact upon the affected species or stocks and their habitat (50 CFR
216.104(a)(11)).
In evaluating how mitigation may or may not be appropriate to
ensure the least practicable adverse impact on species or stocks and
their habitat, as well as subsistence uses where applicable, we
carefully consider two primary factors:
(1) The manner in which, and the degree to which, the successful
implementation of the measure(s) is expected to reduce impacts to
marine mammals, marine mammal species or stocks, and their habitat.
This considers the nature of the potential adverse impact being
mitigated (likelihood, scope, range). It further considers the
likelihood that the measure will be effective if implemented
(probability of accomplishing the mitigating result if implemented as
planned), the likelihood of effective implementation (probability
implemented as planned), and;
(2) the practicability of the measures for applicant
implementation, which may consider such things as cost, impact on
operations, and, in the case
[[Page 59790]]
of a military readiness activity, personnel safety, practicality of
implementation, and impact on the effectiveness of the military
readiness activity.
In addition to the measures described later in this section, the
City will employ the following standard mitigation measures:
The City shall conduct briefings between construction
supervisors and crews, marine mammal monitoring team, and City staff
prior to the start of all construction work, and when new personnel
join the work, in order to explain responsibilities, communication
procedures, marine mammal monitoring protocol, and operational
procedures;
For those marine mammals for which Level B harassment take
has not been requested, in-water pile installation/removal and drilling
will shut down immediately if such species are observed within or on a
path towards the monitoring zone (i.e., Level B harassment zone); and
If observed take reaches the authorized limit for an
authorized species, pile installation will be stopped as these species
approach the Level B harassment zone to avoid additional take.
The following measures would apply to the City's mitigation
requirements:
Establishment of Shutdown Zones--For all pile driving/removal and
drilling activities, the City will establish appropriate shutdown
zones. The purpose of a shutdown zone is generally 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).
These shutdown zones would be used to prevent incidental Level A
exposures from pile driving and removal for Steller sea lions, and to
reduce the potential for such take of harbor seals and California sea
lions. During all pile driving and removal activities, as well as
above-water construction, a minimum shutdown zone of 10m would be
enforced (Table 16) for all species to prevent physical injury from
interaction with construction equipment. Additionally, a shutdown zone
of 32m will be enforced for Steller sea lions during impact pile
driving to reduce the likelihood of Level A harassment take (Table 16).
The placement of Protected Species Observers (PSOs) during all pile
driving and drilling activities (described in detail in the Monitoring
and Reporting Section) will ensure shutdown zones are visible when they
are on site. When PSOs are not on site, the Oregon Department of
Transportation (ODOT) inspector will be responsible for ensuring that
activities shut down if a marine mammal enters the shutdown zone.
Table 16--Shutdown Zones
----------------------------------------------------------------------------------------------------------------
Shutdown zone (m)
------------------------------------------------
Construction activity Steller sea California sea
Harbor seal lion lion
----------------------------------------------------------------------------------------------------------------
All Vibratory Pile Driving/Removal and Site Preparation........ 50 10 10
----------------
24-inch Steel Impact Pile Driving.............................. .............. 32
--------------------------------
Above-water Construction....................................... 10 10
----------------------------------------------------------------------------------------------------------------
Establishment of Monitoring Zones for Level B Harassment--The City
would establish monitoring zones to correlate with Level B harassment
zones or zones of influence. These are areas where SPLs are equal to or
exceed the 160 dB rms threshold for impact driving and the 120 dB rms
threshold during vibratory driving and site preparation. For airborne
noise, these thresholds are 90 dB RMS re 20[mu]Pa for harbor seals and
100 db RMS re: 20[mu]Pa for all other pinnipeds. Monitoring zones
provide utility for observing by establishing monitoring protocols for
areas adjacent to the shutdown zones. Monitoring zones enable observers
to be aware of and communicate the presence of marine mammals in the
project area outside the shutdown zone and thus prepare for a potential
cease of activity should the animal enter the shutdown zone. The
proposed monitoring zones are described in Table 17. Placement of PSOs
on the shorelines around the Columbia River allow PSOs to observe
marine mammals within the project site, however, due to the size of the
Level B harassment zone during some activities, not all Level B
harassment takes will be visible to PSOs. Level B harassment exposures
will be recorded and extrapolated based upon the number of observed
take and the percentage of the Level B zone that was not visible.
Table 17--Marine Mammal Monitoring Zones
------------------------------------------------------------------------
Construction activity Monitoring zone (m)
------------------------------------------------------------------------
Above-water Construction.................. 28 (harbor seal only).
14-inch Timber Vibratory.................. 1,360.
14-inch Steel H-Pile...................... 1,000.
24-inch Steel Vibratory................... 6,310.
36-inch Steel Vibratory................... 21,545.
24-inch Steel Impact...................... 635.
------------------------------------------------------------------------
Soft Start--The use of soft-start procedures are believed to
provide additional protection to marine mammals by providing warning
and/or giving marine mammals a chance to leave the area prior to the
hammer operating at full capacity. For impact driving, an initial set
of three strikes would be made by the hammer at 40 percent energy,
followed by a 1-minute wait period, then two subsequent 3-strike sets
at 40 percent energy, with 1-minute waiting periods, before initiating
continuous driving. Soft start would be implemented at the start of
each day's impact pile driving and at any time following cessation of
impact pile driving for a period of thirty minutes or longer. Soft
start is not required during vibratory pile driving and removal
activities.
Pre-Activity Monitoring--Prior to the start of daily in-water
construction activity, or whenever a break in pile driving/removal or
site preparation of 30 minutes or longer occurs, PSOs will observe the
shutdown and monitoring zones for a period of 30 minutes. The shutdown
zone will be cleared when a marine mammal has not been observed within
the zone for that 30-minute period. If a marine mammal is observed
within the shutdown zone, a soft-start cannot proceed until the animal
has been confirmed to have left the zone or has not been observed for
15 minutes. If the Level B harassment zone has been observed for 30
minutes and non-
[[Page 59791]]
permitted species are not observed within the zone, soft start
procedures can commence and work can continue even if visibility
becomes impaired within the Level B monitoring zone. When a marine
mammal permitted for Level B harassment take is present in the Level B
harassment zone, activities may begin and Level B take will be
recorded. As stated above, if the entire Level B zone is not visible at
the start of construction, piling or drilling activities can begin. If
work ceases for more than 30 minutes, the pre-activity monitoring of
both the Level B and shutdown zone will commence.
Based on our evaluation of the applicant's proposed measures, as
well as other measures considered by NMFS, NMFS has preliminarily
determined that the proposed mitigation measures provide the means
effecting the least practicable impact on the affected species or
stocks and their habitat, paying particular attention to rookeries,
mating grounds, and areas of similar significance.
Proposed Monitoring and Reporting
In order to issue an IHA for an activity, Section 101(a)(5)(D) of
the MMPA states that NMFS must set forth requirements pertaining to the
monitoring and reporting of such taking. The MMPA implementing
regulations at 50 CFR 216.104 (a)(13) indicate that requests for
authorizations must include the suggested means of accomplishing the
necessary monitoring and reporting that will result in increased
knowledge of the species and of the level of taking or impacts on
populations of marine mammals that are expected to be present in the
proposed action area. Effective reporting is critical both to
compliance as well as ensuring that the most value is obtained from the
required monitoring.
Monitoring and reporting requirements prescribed by NMFS should
contribute to improved understanding of one or more of the following:
Occurrence of marine mammal species or stocks in the area
in which take is anticipated (e.g., presence, abundance, distribution,
density);
Nature, scope, or context of likely marine mammal exposure
to potential stressors/impacts (individual or cumulative, acute or
chronic), through better understanding of: (1) Action or environment
(e.g., source characterization, propagation, ambient noise); (2)
affected species (e.g., life history, dive patterns); (3) co-occurrence
of marine mammal species with the action; or (4) biological or
behavioral context of exposure (e.g., age, calving or feeding areas);
Individual marine mammal responses (behavioral or
physiological) to acoustic stressors (acute, chronic, or cumulative),
other stressors, or cumulative impacts from multiple stressors;
How anticipated responses to stressors impact either: (1)
Long-term fitness and survival of individual marine mammals; or (2)
populations, species, or stocks;
Effects on marine mammal habitat (e.g., marine mammal prey
species, acoustic habitat, or other important physical components of
marine mammal habitat);
Mitigation and monitoring effectiveness.
Marine Mammal Visual Monitoring
Monitoring shall be conducted by NMFS-approved observers. Trained
observers shall be placed at the best vantage point(s) practicable to
monitor for marine mammals, and will implement shutdown or delay
procedures when applicable through communication with the equipment
operator. Observer training must be provided prior to project start,
and shall include instruction on species identification (sufficient to
distinguish the species in the project area), description and
categorization of observed behaviors and interpretation of behaviors
that may be construed as being reactions to the specified activity,
proper completion of data forms, and other basic components of
biological monitoring, including tracking of observed animals or groups
of animals such that repeat sound exposures may be attributed to
individuals (to the extent possible).
Monitoring would be conducted 30 minutes before, during, and 30
minutes after pile driving/removal and drilling activities. In
addition, observers shall record all incidents of marine mammal
occurrence, regardless of distance from activity, and shall document
any behavioral reactions in concert with distance from piles being
driven or removed. Pile driving/removal and drilling activities include
the time to install or remove a single pile or series of piles, as long
as the time elapsed between uses of the pile driving equipment is no
more than 30 minutes.
Three PSOs will be on-site the first day and every third day
thereafter during vibratory hammer installation and site preparation at
each bridge. One observer will be stationed at the best practicable
land-based vantage point to observe the Shutdown Zone and a portion of
the Level A and Level B harassment zones. One observer will be
stationed along the north bank of the river at the Washington State
Department of Transportation Rest Area: Dismal Nitch. One observer will
be stationed at the best practicable land-based vantage point to
observe the remainder of the Level A and Level B harassment zones.
Likely locations include the 6th Street viewing platform and the Pier
12 parking lot. If vibratory installation of the 36-inch casings
occurs, this observer will be positioned along the north bank of the
river downstream of the project site within the Chinook County Park.
The ODOT on-site inspector will be trained in species identification
and monitoring protocol and will be on-site during all vibratory
removal and installation activities to confirm that no species enter
the 10-meter Shutdown Zone when PSOs are not onsite.
Two PSOs will be on-site the first day of impact pile driving at
each bridge, and every third day thereafter. One observer will be
stationed at the best practicable land-based vantage point to observe
the Shutdown Zone and a portion of the Level A and Level B harassment
zones. One observer will be stationed at the best practicable land-
based vantage point to observe the remainder of the Level A and Level B
harassment zones. Likely locations include the 6th Street viewing
platform, the Pier 12 parking lot, or the Washington State Department
of Transportation Rest Area: Dismal Nitch on the north bank of the
river. The ODOT on-site inspector will be trained in species
identification and monitoring protocol and will be on-site during all
impact pile driving activities to confirm that no species enter the 10-
meter Shutdown Zone when PSOs are not onsite.
PSOs would scan the waters using binoculars, and/or spotting
scopes, and would use a handheld GPS or range-finder device to verify
the distance to each sighting from the project site. All PSOs would be
trained in marine mammal identification and behaviors and are required
to have no other project-related tasks while conducting monitoring. In
addition, 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. The City would
adhere to the following observer qualifications:
(i) Independent observers (i.e., not construction personnel) are
required.
[[Page 59792]]
(ii) At least one observer must have prior experience working as an
observer.
(iii) Other observers may substitute education (degree in
biological science or related field) or training for experience.
(iv) The City must submit observer CVs for approval by NMFS.
Additional standard observer qualifications include:
Ability to conduct field observations and collect data
according to assigned protocols Experience or training in the field
identification of marine mammals, including the identification of
behaviors;
Sufficient training, orientation, or experience with the
construction operation to provide for personal safety during
observations;
Writing skills sufficient to prepare a report of
observations including but not limited to the number and species of
marine mammals observed; dates and times when in-water construction
activities were conducted; dates 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
Ability to communicate orally, by radio or in person, with
project personnel to provide real-time information on marine mammals
observed in the area as necessary.
A draft marine mammal monitoring report would be submitted to NMFS
within 90 days after the completion of site preparation and pile
driving and removal activities. It will include an overall description
of work completed, a narrative regarding marine mammal sightings, and
associated PSO data sheets. Specifically, the report must include:
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.
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 addressing NMFS comments must be submitted
within 30 days after receipt of comments.
In the unanticipated event that the specified activity clearly
causes the take of a marine mammal in a manner prohibited by the IHA
(if issued), such as an injury, serious injury or mortality, the City
would immediately cease the specified activities and report the
incident to the Chief of the Permits and Conservation Division, Office
of Protected Resources, NMFS, and the West Coast Regional Stranding
Coordinator. The report would include the following information:
Description of the incident;
Environmental conditions (e.g., Beaufort sea state,
visibility);
Description of all marine mammal observations in the 24
hours preceding the incident;
Species identification or description of the animal(s)
involved;
Fate of the animal(s); and
Photographs or video footage of the animal(s) (if
equipment is available).
Activities would not resume until NMFS is able to review the
circumstances of the prohibited take. NMFS would work with the City to
determine what is necessary to minimize the likelihood of further
prohibited take and ensure MMPA compliance. The City would not be able
to resume their activities until notified by NMFS via letter, email, or
telephone.
In the event that the City discovers an injured or dead marine
mammal, and the lead PSO determines that the cause of the injury or
death is unknown and the death is relatively recent (e.g., in less than
a moderate state of decomposition as described in the next paragraph),
the City would immediately report the incident to the Chief of the
Permits and Conservation Division, Office of Protected Resources, NMFS,
and the NMFS West Coast Stranding Hotline and/or by email to the West
Coast Regional Stranding Coordinator. The report would include the same
information identified in the paragraph above. Activities would be able
to continue while NMFS reviews the circumstances of the incident. NMFS
would work with the City to determine whether modifications to the
activities are appropriate.
In the event that the City discovers an injured or dead marine
mammal and the lead PSO determines that the injury or death is not
associated with or related to the activities authorized in the IHA
(e.g., previously wounded animal, carcass with moderate to advanced
decomposition, or scavenger damage), the City would report the incident
to the Chief of the Permits and Conservation Division, Office of
Protected Resources, NMFS, and the NMFS West Coast Stranding Hotline
and/or by email to the West Coast Regional Stranding Coordinator,
within 24 hours of the discovery. The City would provide photographs,
video footage (if available), or other documentation of the stranded
animal sighting to NMFS and the Marine Mammal Stranding Network.
Phase 1 Monitoring Report
The City's monitoring report from Phase 1 of the project (OBEC,
2019) was frequently consulted in the NMFS evaluation of the City's
proposed activities and requested take for Phase 2 of the project. The
Phase 1 monitoring report indicated recorded take of California sea
lions and harbor seals (Table 18). Steller sea lions were not observed
during Phase 1 (Table 18), however, due to their known presence in the
area, Level B harassment take was still requested for Phase 2
activities. Additionally, as mentioned above, the calculated Level B
harassment zones were significantly smaller for Phase 1 than for Phase
2.
Table 18--Phase 1 Monitoring Results
----------------------------------------------------------------------------------------------------------------
Total
Number of Estimated takes estimated Authorized Percent of
Species takes recorded on days PSOs not Level B Level B authorized
by PSOs present harassment harassment takes that
takes take number occurred
----------------------------------------------------------------------------------------------------------------
California sea lion........... 604 3,600 (240 x 15 4204 33,736 12.5
days).
Steller sea lion.............. 0 0............... 0 5,360 0
Pacific harbor seal........... 53 270 (18 x 15 323 4,560 7.1
days).
----------------------------------------------------------------------------------------------------------------
[[Page 59793]]
Level A take was not requested nor authorized for Phase 1
activities, so the City used the calculated Level A isopleth as the
shutdown zone to prevent Level A take. Shutdowns occurred on three days
during Phase 1 activities. In all instances, shutdowns occurred when
one or more California sea lion entered the shutdown zone. The Phase 1
and Phase 2 monitoring reports will provide useful information for
analyzing impacts to marine mammals for potential future projects in
the lower Columbia River.
Negligible Impact Analysis and Determination
NMFS has defined negligible impact as an impact resulting from the
specified activity that cannot be reasonably expected to, and is not
reasonably likely to, adversely affect the species or stock through
effects on annual rates of recruitment or survival (50 CFR 216.103). A
negligible impact finding is based on the lack of likely adverse
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough
information on which to base an impact determination. In addition to
considering estimates of the number of marine mammals that might be
``taken'' through harassment, NMFS considers other factors, such as the
likely nature of any responses (e.g., intensity, duration), the context
of any responses (e.g., critical reproductive time or location,
migration), as well as effects on habitat, and the likely effectiveness
of the mitigation. We also assess the number, intensity, and context of
estimated takes by evaluating this information relative to population
status. Consistent with the 1989 preamble for NMFS's implementing
regulations (54 FR 40338; September 29, 1989), the impacts from other
past and ongoing anthropogenic activities are incorporated into this
analysis via their impacts on the environmental baseline (e.g., as
reflected in the regulatory status of the species, population size and
growth rate where known, ongoing sources of human-caused mortality, or
ambient noise levels).
Pile driving/removal and drilling activities associated with the
project as outlined previously, have the potential to disturb or
displace marine mammals. Specifically, the specified activities may
result in take, in the form of Level A harassment and Level B
harassment from underwater sounds generated from pile driving and
removal. Potential takes could occur if individuals of these species
are present in zones ensonified above the thresholds for Level A or
Level B harassment, identified above, when these activities are
underway.
The takes from Level A and Level B harassment would be due to
potential behavioral disturbance, TTS, and PTS. No mortality is
anticipated given the nature of the activity. Level A harassment is
only anticipated for California sea lion and harbor seal. The potential
for Level A harassment is minimized through the construction method and
the implementation of the planned mitigation measures (see Proposed
Mitigation section).
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, including Phase 1 of the City's project, 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; HDR, Inc. 2012; Lerma 2014;
ABR 2016; OBEC, 2019). Most likely for pile driving, individuals will
simply move away from the sound source and be temporarily displaced
from the areas of pile driving and drilling, although even this
reaction has been observed primarily only in association with impact
pile driving. The pile driving activities analyzed here are similar to
Phase 1 activities and numerous other construction activities conducted
in the Pacific Northwest, which have taken place with no known long-
term adverse consequences from behavioral harassment. Level B
harassment will be reduced to the level of least practicable adverse
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 area while the activity is
occurring. While vibratory driving (and potential drilling) associated
with the proposed project may produce sound at distances of many
kilometers from the project site, the project site itself is located on
a busy waterfront and in a section of the Columbia River with high
amounts of vessel traffic. Therefore, we expect that animals disturbed
by project sound would simply avoid the area and use more-preferred
habitats.
In addition to the expected effects resulting from authorized Level
B harassment, we anticipate that California sea lions and harbor seals
may sustain some limited Level A harassment in the form of auditory
injury. However, animals in these locations that experience PTS would
likely only receive slight PTS, i.e., minor degradation of hearing
capabilities within regions of hearing that align most completely with
the frequency range of the energy produced by pile driving, i.e., the
low-frequency region below 2 kHz, not severe hearing impairment or
impairment in the regions of greatest hearing sensitivity. If hearing
impairment occurs, it is most likely that the affected animal would
lose a few decibels in its hearing sensitivity, which in most cases is
not likely to meaningfully affect its ability to forage and communicate
with conspecifics. As described above, we expect that marine mammals
would be likely to move away from a sound source that represents an
aversive stimulus, especially at levels that would be expected to
result in PTS, given sufficient notice through use of soft start.
The project also is not expected to have significant adverse
effects on affected marine mammals' habitat. The project activities
would not modify existing marine mammal habitat for a significant
amount of time. The activities may cause some fish to leave the area of
disturbance, thus temporarily impacting marine mammals' foraging
opportunities in a limited portion of the foraging range; but, because
of the short duration of the activities and the relatively small area
of the habitat that may be affected, the impacts to marine mammal
habitat are not expected to cause significant or long-term negative
consequences. Other than feeding and the haulout areas previously
described, the project area does not include any areas or times of
particular biological significance for the affected species.
In summary and as described above, the following factors primarily
support our preliminary determination that the impacts resulting from
this activity are not expected to adversely affect the species or stock
through effects on annual rates of recruitment or survival:
No mortality or serious injury is anticipated or
authorized;
No serious injury is anticipated or authorized;
The Level A harassment exposures are anticipated to result
only in slight PTS, within the lower frequencies associated with pile
driving;
The anticipated incidents of Level B harassment would
consist of, at worst, temporary modifications in behavior that would
not result in fitness impacts to individuals;
The area impacted by the specified activity is very small
relative to the overall habitat ranges of all species;
The activity is expected to occur over 21 or fewer in-
water work days.
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals
[[Page 59794]]
and their habitat, and taking into consideration the implementation of
the proposed monitoring and mitigation measures, NMFS preliminarily
finds that the total marine mammal take from the proposed activity will
have a negligible impact on all affected marine mammal species or
stocks.
Small Numbers
As noted above, only small numbers of incidental take may be
authorized under Sections 101(a)(5)(A) and (D) of the MMPA for
specified activities other than military readiness activities. The MMPA
does not define small numbers and so, in practice, where estimated
numbers are available, NMFS compares the number of individuals taken to
the most appropriate estimation of abundance of the relevant species or
stock in our determination of whether an authorization is limited to
small numbers of marine mammals. Additionally, other qualitative
factors may be considered in the analysis, such as the temporal or
spatial scale of the activities.
The number of takes for each species proposed to be taken as a
result of this project is 5, 13.7, and 10.2 percent of the total stock
for harbor seal, Steller sea lion, and California sea lion,
respectively (Table 15). Additionally, the number of takes requested is
based on the number of estimated exposures, not necessarily the number
of individuals exposed. Pinnipeds may remain in the general area of the
project sites and the same individuals may be harassed multiple times
over multiple days, rather than numerous individuals harassed once.
Based on the analysis contained herein of the proposed activity
(including the proposed mitigation and monitoring measures) and the
anticipated take of marine mammals, NMFS preliminarily finds that small
numbers of marine mammals will be taken relative to the population size
of the affected species or stocks.
Unmitigable Adverse Impact Analysis and Determination
There are no relevant subsistence uses of the affected marine
mammal stocks or species implicated by this action. Therefore, NMFS has
preliminarily determined that the total taking of affected species or
stocks would not have an unmitigable adverse impact on the availability
of such species or stocks for taking for subsistence purposes.
Endangered Species Act (ESA)
Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 16
U.S.C. 1531 et seq.) requires that each Federal agency insure that any
action it authorizes, funds, or carries out is not likely to jeopardize
the continued existence of any endangered or threatened species or
result in the destruction or adverse modification of designated
critical habitat. To ensure ESA compliance for the issuance of IHAs,
NMFS consults internally, in this case with the NMFS West Coast Region
Protected Resources Division Office, whenever we propose to authorize
take for endangered or threatened species.
No incidental take of ESA-listed species is proposed for
authorization or expected to result from this activity. Therefore, NMFS
has determined that formal consultation under Section 7 of the ESA is
not required for this action.
Proposed Authorization
As a result of these preliminary determinations, NMFS proposes to
issue an IHA to the City of Astoria for conducting waterfront bridge
removal and replacement in Astoria, Oregon from November 2019 to
October 2020, provided the previously mentioned mitigation, monitoring,
and reporting requirements are incorporated. A draft of the proposed
IHA can be found at https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act.
Request for Public Comments
We request comment on our analyses, the proposed authorization, and
any other aspect of this Notice of Proposed IHA for the proposed
project. We also request at this time comment on the potential renewal
of this proposed IHA as described in the paragraph below. Please
include with your comments any supporting data or literature citations
to help inform decisions on the request for this IHA or a subsequent
Renewal.
On a case-by-case basis, NMFS may issue a one-year IHA renewal with
an additional 15 days for public comments when (1) another year of
identical or nearly identical activities as described in the Specified
Activities section of this notice is planned or (2) the activities as
described in the Specified Activities section of this notice would not
be completed by the time the IHA expires and a Renewal would allow for
completion of the activities beyond that described in the Dates and
Duration section of this notice, provided all of the following
conditions are met:
A request for renewal is received no later than 60 days
prior to expiration of the current IHA.
The request for renewal must include the following:
(1) An explanation that the activities to be conducted under the
requested Renewal are identical to the activities analyzed under the
initial IHA, are a subset of the activities, or include changes so
minor (e.g., reduction in pile size) that the changes do not affect the
previous analyses, mitigation and monitoring requirements, or take
estimates (with the exception of reducing the type or amount of take
because only a subset of the initially analyzed activities remain to be
completed under the Renewal).
(2) A preliminary monitoring report showing the results of the
required monitoring to date and an explanation showing that the
monitoring results do not indicate impacts of a scale or nature not
previously analyzed or authorized.
Upon review of the request for Renewal, the status of the
affected species or stocks, and any other pertinent information, NMFS
determines that there are no more than minor changes in the activities,
the mitigation and monitoring measures will remain the same and
appropriate, and the findings in the initial IHA remain valid.
Dated: October 31, 2019.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2019-24190 Filed 11-5-19; 8:45 am]
BILLING CODE 3510-22-P
