Rule2026-09884
Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to the Interstate Bridge Replacement Project on Interstate 5 between Portland, OR, and Vancouver, WA
Primary source
Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.
Published
May 18, 2026
Effective
September 15, 2027
Issuing agencies
Commerce DepartmentNational Oceanic and Atmospheric Administration
Abstract
NMFS, upon request from the Interstate Bridge Replacement Program (IBRP), issues this final rule and associated 5-year letter of authorization (LOA) pursuant to the Marine Mammal Protection Act (MMPA), to govern the taking of marine mammals incidental to construction activities conducted in support of the Interstate Bridge Replacement Project (IBR Project) on Interstate 5 (I-5) between Portland, Oregon, and Vancouver, Washington, over the course of 5 years. This final rule prescribes the permissible methods of taking and other means of effecting the least practicable adverse impact on marine mammal species and their habitat and establishes requirements pertaining to the monitoring and reporting of such taking.
Full Text
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<title>Federal Register, Volume 91 Issue 95 (Monday, May 18, 2026)</title>
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[Federal Register Volume 91, Number 95 (Monday, May 18, 2026)]
[Rules and Regulations]
[Pages 28443-28458]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-09884]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
50 CFR Part 217
[Docket No. 260513-0130]
RIN 0648-BN34
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to the Interstate Bridge Replacement
Project on Interstate 5 between Portland, OR, and Vancouver, WA
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Final rule; notice of issuance of letter of authorization.
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SUMMARY: NMFS, upon request from the Interstate Bridge Replacement
Program (IBRP), issues this final rule and associated 5-year letter of
authorization (LOA) pursuant to the Marine Mammal Protection Act
(MMPA), to govern the taking of marine mammals incidental to
construction activities conducted in support of the Interstate Bridge
Replacement Project (IBR Project) on Interstate 5 (I-5) between
Portland, Oregon, and Vancouver, Washington, over the course of 5
years. This final rule prescribes the permissible methods of taking and
other means of effecting the least practicable adverse impact on marine
mammal species and their habitat and establishes requirements
pertaining to the monitoring and reporting of such taking.
DATES: This final rule and LOA are effective from September 15, 2027,
through September 14, 2032.
ADDRESSES: Electronic copies of the LOA, application, supporting
documents, and a list of the references cited in this document, may be
obtained online at: <a href="https://www.fisheries.noaa.gov/action/incidental-take-authorization-interstate-bridge-replacement-programs-interstate-bridge">https://www.fisheries.noaa.gov/action/incidental-take-authorization-interstate-bridge-replacement-programs-interstate-bridge</a>. In case of problems accessing these documents, please call the
contact listed below.
FOR FURTHER INFORMATION CONTACT: Cara Hotchkin, Office of Protected
Resources, NMFS, (301) 427-8401.
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
[[Page 28444]]
(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 promulgated and a LOA is issued or an incidental
harassment authorization (IHA) is issued.
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). If such findings are made, 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
the species or stocks for taking for certain subsistence uses (referred
to in shorthand as ``mitigation''); and set forth requirements
pertaining to the monitoring and reporting of the takings. The
definitions of applicable MMPA statutory terms are provided directly
below or included in the relevant sections of this rule.
<bullet> U.S. citizen--individual U.S. citizens or any corporation
or similar entity if it is organized under the laws of the United
States or any governmental unit defined in 16 U.S.C. 1362(13); 50 CFR
216.103;
<bullet> Take--to harass, hunt, capture, or kill, or attempt to
harass, hunt, capture, or kill any marine mammal (16 U.S.C. 1362(13));
<bullet> Incidental harassment, incidental taking, and incidental,
but not intentional, taking--an accidental taking. This does not mean
that the taking is unexpected, but rather it includes those takings
that are infrequent, unavoidable or accidental (50 CFR 216.103);
<bullet> Level A harassment--any act of pursuit, torment, or
annoyance which has the potential to injure a marine mammal or marine
mammal stock in the wild (16 U.S.C. 1362(18); 50 CFR 216.3); and
<bullet> Level B harassment--any act of pursuit, torment, or
annoyance which 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 (16 U.S.C. 1362(18); 50 CFR 216.3).
Purpose of Regulatory Action
NMFS received an application from the IBRP requesting 5-year
regulations and a LOA issued thereunder to take individuals of three
species (California sea lion, Steller sea lion, and harbor seal),
comprising three stocks of marine mammals, by Level A harassment and
Level B harassment incidental to the IBRP's activities. No serious
injury or mortality is anticipated or authorized. Please see the
Background section for definitions of harassment.
These regulations, promulgated under the authority of the MMPA (16
U.S.C. 1361 et seq.), provide a framework for authorizing the take of
marine mammals incidental to construction activities associated with
the IBR Project, including impact and vibratory pile driving. The
regulations include mitigation, monitoring, and reporting requirements.
These requirements, which were proposed by IBRP, are expected to
minimize the number and/or intensity of incidents of marine mammal
take, as well as to provide information to better understand the
impacts of the action and document compliance. IBRP has agreed that all
of the mitigation measures are practicable. As required by the MMPA,
NMFS concurred that these measures are sufficient to achieve the least
practicable adverse impact on the affected marine mammal species or
stocks and their habitat.
Legal Authority for the Action
Section 101(a)(5)(A) of the MMPA (16 U.S.C. 1371(a)(5)(A)) directs
the Secretary of Commerce to allow, upon request, the incidental, but
not intentional taking of small numbers of marine mammals by U.S.
citizens who engage in a specified activity (other than commercial
fishing) within a specified geographical region for up to 5 years if,
after notice and public comment, the agency makes certain findings and
promulgates regulations that set forth permissible methods of taking
pursuant to that activity and other means of effecting the ``least
practicable adverse impact'' on the affected species or stocks and
their habitat (see the discussion below in the Mitigation section), as
well as monitoring and reporting requirements. Section 101(a)(5)(A) of
the MMPA and the implementing regulations at 50 CFR part 216, subpart I
provide the legal basis for issuing this rule containing 5-year
regulations and a 5-year LOA.
Summary of Major Provisions Within the Rule
Following is a summary of the major provisions of this rule
regarding the IBRP's activities. These measures include:
<bullet> Prescribing permissible methods of taking of small numbers
of marine mammals by Level A harassment and/or Level B harassment
incidental to the IBR Project;
<bullet> Required monitoring of the construction areas to detect
the presence of marine mammals before beginning construction
activities;
<bullet> Establishment of shutdown zones;
<bullet> Bubble curtains required for impact driving of steel piles
except as necessary to verify bubble curtain effectiveness during
hydroacoustic monitoring;
<bullet> Soft start for impact pile driving to allow marine mammals
the opportunity to leave the area prior to beginning impact pile
driving at full power;
<bullet> Submittal of monitoring reports including a summary of
marine mammal species and behavioral observations, construction
shutdowns or delays, and construction work completed; and
<bullet> Hydroacoustic monitoring to verify effectiveness of noise
attenuation devices and sound source level assumptions for modeling.
Through adaptive management, the regulations allow NMFS Office of
Protected Resources to modify (e.g., remove, revise, or add to) the
existing mitigation, monitoring, or reporting measures summarized above
and required by the LOA.
Summary of Request
On July 18, 2024, NMFS received an application from the IBRP
requesting authorization for take of marine mammals incidental to
construction activities related to the IBR Project on I-5 between
Portland, OR, and Vancouver, WA. After the IBRP responded to our
questions on October 12, 2024, and January 14, 2025, we determined the
application was adequate and complete on January 16, 2025. We published
a notice of receipt in the Federal Register on March 13, 2025 (90 FR
11950, March 13, 2025) and received 38 comments. Of these, 37 were
opposed to the IBR Project; most suggested an alternative project
design unrelated to IBRP's request for incidental take authorization,
and which are outside the scope of NMFS' action in promulgating
regulations under the MMPA because the design of the project is at the
discretion of the IBRP. One comment letter expressed support for the
IBR Project and the potential associated
[[Page 28445]]
increases in employment and training opportunities for ironworkers.
NMFS determined that these comments did not provide information
relevant to our decision under the MMPA. On August 19, 2025, NMFS
published a proposed rule (90 FR 40492) (Proposed Rule) and a request
for public comments in the Federal Register; we received three total
comments on the proposed rule, none of which were relevant to our
findings due to a lack of substantive information provided or because
the comments were on issues outside the scope of NMFS' action (i.e., on
the project's design).
Changes From the Proposed to Final Rule
There have been several changes from the proposed rule in this
final rule. First, in the Estimated Take of Marine Mammals section
(table 10 of the Proposed Rule; table 3 of this final rule), the proxy
source levels for vibratory driving have been adjusted. This minor
change was made to account for the discrepancy between measured and
assumed values noted in footnote 4 of table 10 in the Proposed Rule.
Specifically, single-hammer vibratory driving proxy source levels have
been revised from 175 decibels (dB) root mean square (RMS) re 1
micropascal ([micro]Pa) to 170 dB RMS re 1 [micro]Pa and associated
proxy sound levels (for simultaneous vibratory driving of two piles)
have been adjusted from 178 dB RMS to 173 dB RMS, following the
methodology outlined in the Proposed Rule for additive sources. The
associated Level A and Level B harassment isopleths have been
recalculated and are shown in table 4 of this final rule. These changes
are small and result in no impact to the estimated take of marine
mammals because of the curvature of the river restricting the
propagation of sound up and downstream. There were small reductions to
the AUD INJ harassment zone isopleths and ensonified areas that are
shown in table 3 of this rule.
Secondly, proxy sound levels (dB peak) for simultaneous impact
driving of two 24-inch (in) piles and for two 48-in piles were
incorrectly calculated in the proposed rule. They have been corrected;
these are now 201 dB peak and 210 dB peak, respectively. The RMS and
single-strike sound exposure level (SEL<INF>ss</INF>) values shown in
the proposed rule were correct and have not changed, and no changes
were made to the resulting Level A or Level B harassment zone isopleths
and associated estimates of exposures.
Thirdly, the Proposed Monitoring and Reporting section of the
Proposed Rule and section 217.146(e)(v) of the proposed regulatory text
incorrectly included hydroacoustic monitoring of vibratory pile
driving; this language has been removed from the final rule. The
inclusion of hydroacoustic monitoring for vibratory pile driving was
purely a clerical error; monitoring of impact driving is required under
the applicant's U.S. Army Corps of Engineers consultation due to
potential injurious take of endangered salmonid fishes. Vibratory
driving has no potential for injurious take of fishes, and thus no
hydroacoustic monitoring is required under that consultation.
Hydroacoustic monitoring of impact driving is planned and remains
included in this final rule.
Finally, in the regulatory text, the following changes were made:
all of section 217.145(a)(4)(ii), and part of section
217.145(a)(6)(iii) were deleted to remove confusion about whether the
shutdown zone must be fully visible in order to be effectively
monitored during short periods of adverse weather conditions; section
217.145(a)(6)(v) was deleted to reduce redundancy in the regulatory
text with section 217.145(a)(3); and section 217.147(c) was deleted
because the LOA as issued is valid for the duration of the effective
dates. Additionally, Sec. 217.146(d)(4) of the proposed rule was
missing a standard requirement to report the number of marine mammals
detected within the harassment zones, by species. This language has
been added to the regulatory text (Sec. 217.146(d)(4)(ix)) and the
associated LOA. Other clerical errors such as numbering were corrected
and clerical changes corresponding to the substantive changes described
above were made as needed.
Description of Specified Activity
Overview
The IBR Project will improve I-5 corridor mobility by addressing
present and future travel demand and mobility needs in the IBR Project
area. The project consists of multiple components and interchanges,
extending from approximately Columbia Boulevard in the south to State
Route (SR) 500 in the north; one component of the project is to replace
the existing bridges over the Columbia River and North Portland Harbor
to accommodate increasing travel demand and congestion, improve safety
related to traffic accidents, and reduce vulnerability to seismic
events. The existing bridges do not meet current seismic standards and
are vulnerable to failure in an earthquake. The IBR Project is
anticipated to take approximately 9 to 15 years to complete and will
require in-water work in up to 9 construction seasons. These
regulations are effective for the first 5 construction years (2027-
2032). IBRP anticipates requesting additional future incidental take
authorizations as necessary in association with subsequent years of
construction.
Exact project sequencing is still in development; however, it is
currently anticipated that work to be conducted during the first 5
years of the IBR Project will include construction of the new Columbia
River Bridge and associated approaches, and construction of the transit
bridge crossing the North Portland Harbor. In-water pile driving for
the first 5 construction years will include both impact and vibratory
driving of temporary steel pipe (24- in (0.61 meters (m)) and 48-in
(1.2 m) diameter) and steel sheet piles. Permanent bridge foundations
will be constructed using 10-foot (ft) (3-m) diameter steel casings
installed with an oscillator, analogous to a rotary drill. Impact
driving would be conducted primarily with the use of a bubble curtain,
with a minimal amount of unattenuated driving to confirm bubble curtain
effectiveness. In-water pile driving associated with the project will
include installation and potential removal of approximately 1,560
temporary steel pipe piles, and 1,500 linear ft (457 m) of steel sheet
piles over the 5-year period.
Dates and Duration
IBRP anticipates that in-water construction activities associated
with this project will begin on September 15, 2027, and extend through
September 14, 2032. In-water pile installation for the first 5 years of
the IBR Project is expected to occur on approximately 1,725 non-
consecutive days. While the exact project design and sequence of
construction are not yet finalized, in-water project elements and
estimated durations are shown in table 1. Land-based project elements
do not have the potential to cause take of marine mammals; for a
description and information on the duration of land-based elements,
please see the Proposed Rule. Construction timing, sequencing, and
duration are dependent on funding, design assumptions, contractor
schedules and equipment, and weather, among other factors. The duration
estimates shown are based on the best available information at the time
of publication of this final rule; however, the schedule may shift such
that actual activities occur in different years than specified below.
Impact driving will be restricted to an in-water work window
between September 15 and April 15 of each year.
[[Page 28446]]
This window was determined via coordination with state (Oregon
Department of Fish and Wildlife (ODFW) and Washington Department of
Fish and Wildlife (WDFW)) and Federal (U.S. Army Corps of Engineers,
Federal Highway Administration, Federal Transit Administration, and
NMFS) agencies, Tribal parties, and public input to reduce potential
impacts to Endangered Species Act (ESA)-listed fishes. Vibratory pile
driving will occur year-round.
Table 1--In-Water Project Elements, Locations and Estimated Durations for the IBR Project
----------------------------------------------------------------------------------------------------------------
Project element Estimated duration Element location Notes
----------------------------------------------------------------------------------------------------------------
Columbia River Bridges............. 4 to 7 years.......... In-water.............. Years 1-5: Construction is
likely to begin with the
main river bridges.
General sequence will
include initial
preparation and
installation of foundation
piles, shaft caps, pier
columns, superstructure,
and deck.
North Portland Harbor Bridges...... 4 to 10 years......... In-water.............. Years 1-5: Existing North
Portland Harbor bridge
will be demolished in
phases to accommodate
traffic during
construction of the new
bridges.
Demolition of the existing 1.5 to 3 years........ In-water.............. Years 6-15: Demolition of
Interstate Bridge. the existing Interstate
Bridge could begin only
after tra[fflig]ic is
rerouted to the new
Columbia River bridges.
----------------------------------------------------------------------------------------------------------------
Specified Geographical Region
The IBR Project will replace the bridge spans across the Columbia
River and North Portland Harbor and the associated highway interchanges
on an approximately 5-mile (mi) (8 kilometer (km)) stretch of I-5
between Portland, OR, and Vancouver, WA (figure 1). In-water work will
occur in the subset of the IBR Project area between the north bank of
the Columbia River in Washington and the south shore of the North
Portland Harbor in Oregon, between river miles 106 and 107. The widths
of the Columbia River and North Portland Harbor at this location are
approximately 0.5 mi (841 m) and 0.18 mi (295 m), respectively.
[[Page 28447]]
[GRAPHIC] [TIFF OMITTED] TR18MY26.000
Figure 1--Overview of IBR Project Location along I-5 between Portland,
OR, and Vancouver, WA
Detailed Description of the Specified Activity
A detailed description of IBRP's planned activities are provided in
the Proposed Rule. Since publication of the proposed rule, IBRP has not
made any modifications to their activities; therefore, we direct the
reader to the proposed rule for a detailed description. Similar to the
proposed rule, mitigation, monitoring, and reporting measures proposed
by IBRP, and included in this final rule are, described in detail later
in this document (please see Mitigation and Monitoring and Reporting).
Description of Marine Mammals in the Area of Specified Activities
Three species of marine mammals, comprising three stocks, may be
taken by harassment incidental to IBRP's specified activities. A
complete description of marine mammal status and trends, life history,
habitat use, and threats is included in IBRP's application and NMFS'
Proposed Rule. These details are not repeated here except for the
reference table containing status, stock abundance, potential
biological removal levels, and annual rates of mortality and serious
injury (table 2).
[[Page 28448]]
Table 2--Species With Estimated Take From the Specified Activities
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Annual
ESA/ MMPA status; Stock abundance Nbest, Potential Mortality/
Common name Scientific name MMPA Stock strategic (Y/N) (CV, Nmin, most recent Biological Serious
\1\ abundance survey) \2\ Removal Injury (M/
(PBR) SI) \3\
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Order Carnivora--Superfamily Pinnipedia
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Family Otariidae (eared seals and
sea lions):
California sea lion............ Zalophus californianus U.S................... -, -, N 257,606 (N/A, 233,515, 14,011 >321
2014).
Steller sea lion............... Eumetopias jubatus.... Eastern............... -, -, N 36,308 (N/A, 36,308, 2,178 93.2
2022) \4\.
Family Phocidae (earless seals):
Harbor seal.................... Phoca vitulina........ OR/WA Coastal......... -, -, N 22,549 (UND, 19,561, UND \6\ 10.6
2022) \ 5\.
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\1\ 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 (SARs) online at: <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments">https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments</a> assessments. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable (N/A).
\3\ These values, found in NMFS' 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.
\4\ Nest is best estimate of counts, which have not been corrected for animals at sea during abundance surveys. Estimates provided are for the United
States only.
\5\ Most recent SAR does not include an abundance estimate for this stock. These data are for the Washington coast and thus underestimate the size of
the OR/WA Coastal stock; estimates are from Pearson et al. (2024).
\6\ UND means undetermined.
Potential Effects of Specified Activities on Marine Mammals and Their
Habitat
The effects of underwater noise from the IBRP's construction
activities have the potential to result in harassment of marine mammals
in the Columbia River. We refer the reader to the Proposed Rule for a
full discussion of the effects of anthropogenic noise on marine mammals
in general and the potential effects of the specified activities on
marine mammals and their habitat. There is no newly available relevant
information that would change our analyses or the results thereof.
Estimated Take of Marine Mammals
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 acoustic sources (i.e., pile driving activities) have the
potential to result in disruption of behavioral patterns for individual
marine mammals. There is also some potential for auditory injury (AUD
INJ) (Level A harassment) to result, primarily for phocids because
predicted AUD INJ zones are larger than for otariids. The required
mitigation and monitoring measures are expected to minimize the
potential for take and, if take were to occur, the severity of the
taking to the extent practicable. As described previously, no serious
injury or mortality is anticipated or proposed to be authorized for
this activity.
This final rule incorporates the harassment thresholds used in the
proposed rule to estimate the manner and number of takes analyzed in
this final rule and LOA. In summary, IBRP's proposed activity includes
the use of continuous (vibratory pile driving and extraction) and
impulsive (impact pile driving) sources, and therefore the RMS sound
pressure level (SPL) thresholds of 120 and 160 dB re 1[micro]Pa are
applicable. NMFS also applied the Updated Acoustic Technical Guidance
(NMFS, 2024) to determine the potential for Level A harassment, as
described in the proposed rule.
Since publication of the proposed rule, NMFS has revised our
consideration of the proposed source values for vibratory pile driving
to account for the discrepancy between measured and assumed values
noted in footnote 4 of table 10 in the Proposed Rule. Specifically, we
made the following modifications:
<bullet> Single-hammer vibratory driving proxy source levels have
been revised from 175 dB RMS to 170 dB RMS. Sound pressure levels above
170 dB RMS have not been measured for 24- to 48-in piles at any
location; however, 170 dB RMS at 10 m from the incident pile is
characteristic of the average measured values across locations;
<bullet> Proxy sound levels (dB RMS) for simultaneous vibratory
driving of two piles have been adjusted from 178 dB RMS to 173 dB RMS,
following the methodology outlined in the Proposed Rule for additive
sources; and
<bullet> Proxy sound levels (dB peak) for simultaneous impact
driving of two 24-in piles and for two 48-in piles have been adjusted
due to an error in the proposed rule. The peak values were not
correctly adjusted; these are now 201 dB peak and 210 dB peak,
respectively. The RMS and SEL<INF>ss</INF> values shown in table 10 of
Proposed Rule were correct and have not changed, and no changes were
made to the resulting Level A or Level B harassment zone isopleths and
associated estimates of exposures.
As a result, straight-line distances to Level B harassment
thresholds for vibratory pile driving decreased, but the ensonified
area did not change due to the river curvature and site geography
limiting sound propagation. Table 3 contains updated distances to
thresholds and corresponding areas for vibratory pile driving
activities in both the Columbia River and North Portland Harbor sites.
[[Page 28449]]
Table 3--Updated Calculated Level A and B Harassment Isopleths in the Columbia River and North Portland Harbor
for Vibratory Pile Driving
----------------------------------------------------------------------------------------------------------------
Level A harassment zone (m/km\2\)-- Level B harassment zone (m/km\2\) \
Phocids & Otariids \a\ b\
Pile size and type ---------------------------------------------------------------------------
Proposed Final Proposed Final
----------------------------------------------------------------------------------------------------------------
Columbia River
----------------------------------------------------------------------------------------------------------------
24-in steel pipe (Unattenuated, 236.3; 0.18 219; 0.15 46,414; 17.63 21,544; 17.63
single)............................
48-in steel pipe (Unattenuated,
single)
Steel sheet (Unattenuated, single)
---------------------------------------------------------------------------
24-in and or 48-in and or sheet 374.5; 0.58 348; 0.53 73,564; 17.63 34,145; 17.63
(Unattenuated, concurrent).........
----------------------------------------------------------------------------------------------------------------
North Portland Harbor
----------------------------------------------------------------------------------------------------------------
24-in steel pipe (Unattenuated, 236.3; 0.12 219; 0.11 46,414; 2.25 21,544; 2.25
single)............................
48-in steel pipe (Unattenuated,
single)
Steel sheet (Unattenuated, single)
---------------------------------------------------------------------------
24-in and or 48-in and or sheet 374.5; 0.22 348; 0.20 73,564; 2.25 34,145; 2.25
(Unattenuated, concurrent).........
----------------------------------------------------------------------------------------------------------------
\a\ Level A harassment zones for phocids have been applied to both phocids and otariids in this analysis. The
calculated Level A isopleths for otariids are 73.8 and 117.0 m for single and concurrent scenarios,
respectively.
\b\ Level B harassment ensonified areas are limited by the river curvature and geography of the two locations.
The Proposed Rule included a description of the methodology IBRP
used to estimate exposures from the specified activities. Potential
take, by Level A and Level B harassment, was quantified for all three
species as a guild based on recent surveys done by ODFW and WDFW (15.2
in September through April; 6.7 in May through August), the likelihood
of exposure during each construction activity, and the number of days
estimated for each activity. The estimated exposures for each activity
in a given year were then summed to estimate total annual exposures.
None of the changes in this final rule resulted in changes to the
proposed estimates of take by Level A or Level B harassment (table 4).
Table 4--Calculated Annual and 5-Year Total Estimated Take per Activity by Level A and Level B Harassment
----------------------------------------------------------------------------------------------------------------
Annual Level A Annual Level B Total annual
Activity Year harassment harassment take
----------------------------------------------------------------------------------------------------------------
Impact--Unattenuated.................. 1....................... 8 76 84
2....................... 4 38 42
3....................... 4 38 42
4....................... 4 38 42
5....................... 4 38 42
5-year estimate......... 24 228 252
Impact--Attenuated.................... 1....................... 182 912 1,094
2....................... 152 760 912
3....................... 114 570 684
4....................... 114 570 684
5....................... 114 570 684
5-year estimate......... 676 3,382 4,058
Vibratory............................. 1....................... 0 2,713 2,713
2....................... 0 2,713 2,713
3....................... 0 2,713 2,713
4....................... 0 2,713 2,713
5....................... 0 2,713 2,713
5-year estimate......... 0 13,365 13,365
All Activities.................... Maximum Annual.......... 190 3,701 3,891
5-year estimate......... 700 17,175 17,785
----------------------------------------------------------------------------------------------------------------
The percentages of take estimated by Level A harassment shown in
the Proposed Pule (0 percent for vibratory pile installation and
extraction; 5 percent for unattenuated impact piling; 10 percent for
attenuated impact piling) were based on the activity duration in a
typical day, the estimated Level A harassment isopleths, and the
ability of pinnipeds to avoid the areas with highest sound exposure
levels by swimming through other areas of the river or harbor. The
maximum average travel speed of California sea lions in the Columbia
River moving between the Bonneville Dam and the river mouth has been
calculated at approximately 5.4 km per hour (hr) (Wright et al., 2010).
For animals traveling at half of the maximum speed (2.7 km/hr) to
traverse the entirety of the largest predicted Level A harassment zone
(from 0.52 km downstream to 0.52 km upstream during concurrent impact
driving) would take approximately 22 minutes, and approximately 1 hour
for animals traveling at 1 km/hr. The largest Level
[[Page 28450]]
A harassment zone calculated for 10 continuous hours of vibratory
driving is 0.35 km (total of 0.7 km diameter) and would take an
estimated 16 or 42 minutes for an animal to transit at 2.7 km/hr or 1
km/hr, respectively. The widths of the Columbia River and North
Portland Harbor at the project site are approximately 841 m and 295 m,
respectively. Therefore, animals in the Columbia River could
potentially avoid the Level A harassment area entirely by increasing
their distance from the relevant sound source. Animals in the North
Portland Harbor would not be able to avoid the Level A harassment zone
during transit.
NMFS considers it unlikely that an individual animal would remain
in the 1 km zone immediately adjacent to the project site for more than
2 hours as there are no known resting or foraging areas in this urban,
industrialized portion of the river. However, given the lack of site-
specific observational data, the conservative proportions of take by
Level A harassment presented in table 15 of the Proposed Rule and
repeated in table 4 of this rule remain appropriate. Table 5 shows the
maximum annual amount of take authorized in the LOA by species and
stock, and the percentages of each stock that could be affected.
Table 5--Calculated Maximum Annual Take Authorized by Level A and Level B Harassment including percentage of
Stocks Taken
----------------------------------------------------------------------------------------------------------------
Maximum annual Maximum annual Total maximum Percentage of
Species Stock Level A take Level B take annual take stock taken
----------------------------------------------------------------------------------------------------------------
Harbor seal................... OR/WA Coastal... 190 3,701 3,891 17.3
Steller sea lion.............. Eastern......... 1.5
California sea lion........... U.S............. 10.7
----------------------------------------------------------------------------------------------------------------
Mitigation
The MMPA requires NMFS set forth in regulations the permissible
methods of taking pursuant to the activity and other means of effecting
the least practicable adverse impact on the species or stock and its
habitat, paying particular attention to rookeries, mating grounds, and
areas of similar significance, and on the availability of the species
or stock for taking for certain subsistence uses (referred to in
shorthand as mitigation). 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 the 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
effect the least practicable adverse impact on species or stocks and
their habitat, as well as subsistence uses where applicable, NMFS
considers two primary factors which are described below. For a full
discussion of NMFS' implementation of the least practicable adverse
impact standard, see 89 FR 31488, 31517 (April 24, 2024) as an example.
(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, as
well as subsistence uses. This considers the nature of the potential
adverse impact being mitigated (e.g., 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 of implementation as planned); and
(2) The practicability of the measures for applicant
implementation, which may consider such things as cost and impact on
operations.
This final rule incorporates all mitigation measures contained
within the proposed rule without change. We refer the reader to the
Proposed Rule on those measures and the expected benefit to marine
mammals. In summary, the mitigation measures in this final rule include
providing training of the protocols and operating procedures to all
relevant personnel before the start of all pile driving, soft starts
and bubble curtain use during impact driving, as well as standard
shutdown zones to avoid physical interaction of marine mammals and
construction equipment. IBRP would utilize NMFS-approved protected
species observers (PSOs) during all activities that have the potential
to result in take. As fully described in the Proposed Rule, NMFS has
determined that the mitigation measures proposed by IBRP and contained
within this final rule result in the least practicable adverse impact
on marine mammals.
PSOs
The IBRP must employ PSOs and establish monitoring locations as
described in a NMFS-approved Marine Mammal Monitoring and Mitigation
Plan. For all pile driving activities, land-based PSOs must be
stationed at the best vantage points practicable to monitor for marine
mammals and implement mitigation procedures. A minimum of two locations
must be used to monitor the harassment zones to the maximum extent
possible based on positioning and daily visibility conditions. PSOs
must be able to implement shutdown or delay procedures when applicable
through communication with the equipment operator. Pre-start clearance
monitoring must take place 30 minutes prior to initiation of pile
driving activity (i.e., pre-start clearance monitoring) through 30
minutes post-completion of pile driving activity during periods of
visibility sufficient for the lead PSO to determine that the shutdown
zones are clear of marine mammals. Pile driving may commence only if,
following 30 minutes of observation, it is determined by the lead PSO
that the shutdown zones are clear of marine mammals.
Shutdown Zones
For all pile driving activity, the IBRP must implement shutdown
zones with radial distances shown in table 6. The IBRP, construction
supervisors and crews, PSOs, and relevant IBRP staff must prevent
direct physical interaction with marine mammals during construction
activity. If a marine mammal comes within 10 m of such activity,
operations must cease and vessels must reduce speed to the minimum
level required to maintain steerage and safe working conditions, as
necessary to prevent direct physical interaction.
[[Page 28451]]
If a marine mammal is observed entering or within the shutdown
zone, all pile driving activities at that location must be halted. If
pile driving is halted or delayed due to the presence of a marine
mammal, the activity may not commence or resume until either the animal
has voluntarily left and has been visually confirmed beyond the
shutdown zone or 15 minutes have passed without re-detection of the
animal. In the event of a delay or shutdown of activity resulting from
marine mammals in the shutdown zone, animal behavior must be monitored
and documented. If work ceases for more than 30 minutes, the shutdown
zones must be cleared again for 30 minutes prior to reinitiating pile
driving.
Table 6--Shutdown Zones During Project Activities
----------------------------------------------------------------------------------------------------------------
Monitoring zones (m)
Activity Pile type/size Shutdown zone ---------------------------------------------
(m) Level A Level B
----------------------------------------------------------------------------------------------------------------
Impact--Unattenuated (Single 24-in............ 10 46 1,000
Hammer).
48-in............ 184 5,412
Impact--Attenuated (Single 24-in............ 10 83 341
Hammer).
48-in............ 328 1,848
Impact--Attenuated (Two 24-in............ 10 131 541
Hammers).
48-in............ 521 2,929
Vibratory (Single Hammer)...... 24-in, 48-in, and 10 \a\ 18,593 (upstream) \b\
sheet. 8,230 (downstream) \b\
Vibratory (Two Hammers)........ 24-in, 48-in, and \a\
sheet.
----------------------------------------------------------------------------------------------------------------
Notes: m = meter(s).
\a\ While the results of the underwater noise modeling indicate Level A harassment isopleths exist for
cumulative exposure to underwater noise during vibratory pile driving, take by Level A harassment is not
anticipated, and no Level A harassment Monitoring Zone is proposed for vibratory pile driving.
\b\ PSOs will monitor the Level B harassment zone to the extent possible based on positioning and environmental
conditions.
Soft Start
The IBRP will use soft start techniques when impact pile driving.
Soft start requires contractors to provide an initial set of three
strikes at reduced energy, followed by a 30-second waiting period, then
two subsequent reduced-energy strike sets. A 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 30
minutes or longer. Soft start procedures are used 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.
Noise Attenuation System
The IBRP will use a bubble curtain during impact pile driving in
water depths greater than 0.67 m. The bubble curtain would be operated
as necessary to achieve optimal performance. At a minimum, the bubble
curtain will distribute air bubbles around 100 percent of the piling
circumference for the full depth of the water column, the lowest bubble
ring will be in contact with the substrate for the full circumference
of the ring, and the weights attached to the bottom ring will ensure
100 percent substrate contact. No parts of the ring or other objects
would prevent full substrate contact. In addition, air flow to the
bubblers would be balanced around the circumference of the pile.
A hydroacoustic monitoring plan will be implemented during impact
pile driving to confirm the attenuation device is installed and
functioning as designed. This monitoring program will require some
unattenuated pile strikes to confirm the amount of attenuation provided
by the system. An estimated number of unattenuated pile strikes are
also factored in to account for periods when the bubble curtain may not
be providing sufficient attenuation. IBRP estimates that up to 75
unattenuated strikes may be required for a period of approximately 10
minutes approximately 1 day per week. Testing will occur for up to
approximately 30 days during the 5-year period covered under this LOA,
and on approximately 40 days total over the course of the in-water
construction period.
Monitoring and Reporting
In order to issue take authorization for an activity, section
101(a)(5)(A) 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 while conducting the activities. 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:
<bullet> Occurrence of marine mammal species or stocks in the area
in which take is anticipated (e.g., presence, abundance, distribution,
density);
<bullet> 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 activity; or (4) biological or
behavioral context of exposure (e.g., age, calving or feeding areas);
<bullet> Individual marine mammal responses (behavioral or
physiological) to acoustic stressors (acute, chronic, or cumulative),
other stressors, or cumulative impacts from multiple stressors;
<bullet> How anticipated responses to stressors impact either: (1)
long-term fitness and survival of individual marine mammals; or (2)
populations, species, or stocks;
<bullet> Effects on marine mammal habitat (e.g., marine mammal prey
species, acoustic habitat, or other important
[[Page 28452]]
physical components of marine mammal habitat); and
<bullet> Mitigation and monitoring effectiveness.
IBRP will abide by all monitoring and reporting measures contained
within this final rule and LOA, and a NMFS-approved Marine Mammal
Monitoring and Mitigation Plan. This final rule incorporates all
monitoring measures contained within the Proposed Rule, without change.
We refer the reader to the Proposed Rule for details regarding those
measures and provide a summary of those measures below.
In summary, IBRP will utilize PSOs at least 30 minutes prior to,
during, and 30 minutes after all activities that may result in take of
marine mammals. PSOs will be independent of the activity contractor
(e.g., employed by a subcontractor) and have no other assigned tasks
during monitoring periods. At least one PSO must have prior experience
performing the duties of a PSO during an activity pursuant to a NMFS-
issued ITA or Letter of Concurrence. Other PSOs may substitute other
relevant experience, education (degree in biological science or related
field), or training for prior experience performing the duties of a
PSO.
PSOs should also have the following additional qualifications:
(a) The ability to conduct field observations and collect data
according to assigned protocols;
(b) Experience or training in the field identification of marine
mammals, including the identification of behaviors;
(c) Sufficient training, orientation, or experience with the
construction operation to provide for personal safety during
observations;
(d) Sufficient writing skills to record required information
including but not limited to the number and species of marine mammals
observed; dates and times when in-water construction activities were
conducted; dates, times, and reason for implementation of mitigation
(or why mitigation was not implemented when required); and marine
mammal behavior; and
(e) The 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.
IBRP will also conduct hydroacoustic monitoring of both attenuated
and unattenuated impact pile installation. Although hydroacoustic
monitoring of vibratory pile driving was inadvertently included in the
proposed rule, no hydroacoustic monitoring of vibratory driving is
planned and none is required. Acoustic monitoring must consist of
multiple hydrophones deployed at 10 m and in the far field with a
direct, unobstructed path between the sound source and the hydrophones.
System design and calibration must be appropriate for the expected
sound levels to be recorded, with a frequency response between 20 hertz
(Hz) and 20 kilohertz (kHz). Environmental data must also be collected,
as well as information on the substrate composition, hammer model and
size, hammer energy settings, and any other relevant information.
Further details of the acoustic monitoring are discussed in the
Proposed Rule and are not repeated here.
The reporting measures contained with the Proposed Rule are
included in this final rule with two minor changes. First, references
to reporting requirements for hydroacoustic monitoring of vibratory
pile driving have been removed from the regulatory text. Secondly, in
the regulatory text of the Proposed Rule, Sec. 217.146(d)(4) omitted
standard language requiring the reporting of the number of marine
mammals detected within the harassment zones, by species. This standard
language has been included in Sec. 217.146(d)(4)(ix) of the regulatory
text and section 6(b)(x) of the associated LOA.
The reports must contain dates and times of all marine mammal
monitoring and the construction activities occurring during each daily
observation period, the total duration of driving time for each pile
(vibratory driving), and number of strikes for each pile (impact
driving); environmental conditions during monitoring periods (at
beginning and end of PSO shift and whenever conditions change
significantly). Upon observation of a marine mammal, PSOs must record
the name of the PSO who sighted the animal, observer location, and
construction activity at time of sighting; identification of the animal
to the lowest possible taxonomic level, PSO confidence in
identification, and the composition of the group if there is a mix of
species; distances and bearings of each marine mammal observed in
relation to the pile being driven for each sighting; estimated number
of animals by species and age class; closest point of approach and
estimated time spent within the harassment zone. PSOs must also provide
a description of any marine mammal behavioral observations, including
an assessment of behavioral responses to the activity, the number of
marine mammals detected within the harassment zones, by species, and
detailed information about any implementation of any mitigation, a
description of specific actions that ensued, and resulting changes in
the behavior of the animal, if any. All PSO data must be submitted in
an electronic format that can be queried such as a spreadsheet or
database (i.e., digital images of data sheets are not sufficient).
IBRP will submit interim monthly reports as well as a draft annual
report within 90 calendar days of completion of marine mammal
monitoring each year and a draft 5-year comprehensive summary to NMFS
90 days after the expiration of the regulations. Revised annual and 5-
year reports must be prepared and submitted to NMFS within 30 days
following receipt of any NMFS comments on the draft reports. Details on
how monitoring reports will be submitted to NMFS and the information
required in each report are detailed in the proposed rule and included
in the associated LOA.
Acoustic monitoring report(s) must be submitted on the same
schedule as visual monitoring reports (i.e., within 90 days following
the completion of construction). The acoustic monitoring report must
contain the informational elements described in the acoustic monitoring
plan and, at minimum, must include:
<bullet> Hydrophone equipment and methods: (1) recording device,
sampling rate, calibration details, distance (m) from the pile where
recordings were made; and (2) the depth of water and recording
device(s);
<bullet> Location, identifier, orientation (e.g., vertical,
battered), material, and geometry (shape, diameter, thickness, length)
of pile being driven, substrate type, method of driving during
recordings (e.g., hammer model and energy), and total pile driving
duration;
<bullet> Whether a sound attenuation device is used and, if so, a
detailed description of the device used, its distance from the pile and
hydrophone, and the duration of its use per pile; and
<bullet> For impact pile driving: (1) number of strikes per day and
per pile and strike rate; (2) depth of substrate to penetrate; (3)
decidecade (one-third octave) band spectra in tabular and figure
formats computed on a per-pulse basis, including the arithmetic mean or
median for all computed spectra; (4) pulse duration and median, mean,
maximum, minimum, and number of samples (where relevant) of the
following sound level metrics: (5) RMS SPL; (6) 24-hour sound exposure
level (SEL<INF>24</INF>), peak (PK) SPL, and SEL<INF>ss</INF>.
If no comments are received from NMFS within 30 days after the
submission of the draft report, the draft report would constitute the
final report. If the IBRP received comments from
[[Page 28453]]
NMFS, a final report addressing NMFS' comments would be submitted
within 30 days after receipt of comments. The estimated harassment and
shutdown zones may be modified with NMFS' approval following NMFS'
acceptance of an acoustic monitoring report.
As described in the Proposed Rule, in the event that personnel
involved in IBRP's activities discover an injured or dead marine
mammal, IBRP would report the incident to the Office of Protected
Resources, NMFS (<a href="/cdn-cgi/l/email-protection#7d2d2f5334292d533012131409120f14131a2f180d120f090e3d13121c1c531a120b"><span class="__cf_email__" data-cfemail="18484a36514c4836557776716c776a71767f4a7d68776a6c6b5876777979367f776e">[email protected]</span></a>), and to the West
Coast Regional Stranding Coordinator as soon as feasible. If the death
or injury was clearly caused by the specified activity, IBRP would be
required to immediately cease the specified activities until NMFS is
able to review the circumstances of the incident and determine what, if
any, additional measures are appropriate to ensure compliance with this
final rule. IBRP would not resume their activities until notified by
NMFS. The report must include the time, date, and location (latitude/
longitude) of the first discovery (and updated location information if
known and applicable), the species identification (if known) or
description of the animal(s) involved, the condition of the animal(s)
(including carcass condition if the animal is dead), and the observed
behaviors of the animal(s), if alive. Additionally, the report should
include photographs or video footage of the animal(s), if available,
and the general circumstances under which the animal was discovered.
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 impacts or responses (e.g., intensity, duration),
the context of any impacts or responses (e.g., critical reproductive
time or location, foraging impacts affecting energetics), 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' 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 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).
As described in the Proposed Rule, there are several key factors to
assess whether potential impacts associated with a specified activity
should be considered negligible. These include (but are not limited to)
the type and magnitude of taking, the amount and importance of the
available habitat for the species or stock that is affected, the
duration of the anticipated effect on the individuals, and the status
of the species or stock.
As described in the Changes from Proposed to Final Rule section and
Estimated Take section of this final rule, NMFS identified minor
adjustments to the proxy source level assumptions and methodology that
resulted in small decreases to the ensonified areas within the Level A
harassment zones. However, there was no associated change to the
proposed amount of take by Level A harassment for any species
anticipated to occur incidental to the specified activities. Given
these limited, minor adjustments, NMFS has determined that this new
information does not change any of the preliminary analyses,
conclusions, or determinations in the Proposed Rule. Therefore, the
preliminary analyses, conclusions, and determinations included in the
Proposed Rule for all three species and stocks remain the same for this
final rule. A summary of the expected effects of the taking allowed for
in this final rule, the primary factors considered, and those findings
as provided in the Proposed Rule are described below.
In summary, exposures to elevated sound levels produced during
IBRP's activities may cause behavioral disturbance of some individuals
within the vicinity of the sound source and have the potential to cause
a small amount of slight auditory injury. The amount of annual take
authorized is less than 18 percent of all stocks. NMFS notes that
behavioral responses (e.g., increased swimming speeds, changing
directions of travel and diving and surfacing behaviors, increased
respiration rates, or decreased foraging (if such activity were
occurring) of marine mammals to construction noises are expected to be
mild, short term, and temporary. Marine mammals may not present any
visual cues they are disturbed by activities, or they could become
alert, avoid the area, leave the area, or have other mild responses
that are not observable such as increased stress levels (e.g., Rolland
et al., 2012; Bejder et al., 2006; Rako et al., 2013; Pirotta et al.,
2015; P[eacute]rez-Jorge et al., 2016). They may also exhibit increased
vocalization rates (e.g., Dahlheim, 1987; Dahlheim and Castellote,
2016), louder vocalizations (e.g., Frankel and Gabriele, 2017; Fournet
et al., 2018), alterations in the spectral features of vocalizations
(e.g., Castellote et al., 2012), or a cessation of communication
signals (e.g., Tsujii et al., 2018).
All three marine mammal species present in the region will only be
present temporarily based on seasonal patterns or during transit
between other habitats. Thus, individuals present will be exposed to
only transient periods of noise-generating activity as they move up- or
down-river past the project site. Most likely, individual animals will
either be temporarily deterred from swimming past the construction
activities and will pass by when no pile driving is occurring or will
swim through the area more quickly. Takes may also occur during
important foraging seasons, when anadromous fishes are migrating past
the IBR Project and marine mammals follow. However, the IBR Project
area represents a small portion of available foraging habitat and
impacts on marine mammal feeding for all species are expected to be
minimal. No marine mammal species or individuals are known or expected
to be resident in the IBR Project area, and impacts are unlikely to be
more than temporary and low-intensity.
The intensity of harassment events would be minimized through use
of mitigation measures described herein, which were not quantitatively
factored into the take estimates. As stated in the Mitigation section,
the IBRP will implement shutdown zones (table 6). Take by Level A
harassment will be authorized for all three marine mammal species to
account for the potential that an animal could enter and remain
unobserved within the estimated Level A harassment zone for a duration
long enough to incur AUD INJ. Any take by Level A harassment is
expected to arise from, at most, a small degree of AUD INJ because
animals would need to be exposed to higher levels and/or longer
duration than are expected to occur here in order to incur any more
than a small degree of AUD INJ.
[[Page 28454]]
In summary, the following factors primarily support our negligible
impact determinations for the affected stocks of California sea lions,
Steller sea lions, and harbor seals:
<bullet> No takes by mortality or serious injury are anticipated or
authorized;
<bullet> Any acoustic impacts to marine mammal habitat from pile
driving are expected to be temporary and minimal;
<bullet> Take will not occur in places and/or times where take
would be more likely to accrue impacts on reproduction or survival,
such as within habitats critical to recruitment or survival (e.g.,
rookery);
<bullet> The IBR Project area represents a very small portion of
the available foraging area for all potentially impacted marine mammal
species and does not contain any habitat of particular importance;
<bullet> Take will occur only within the Columbia River and North
Portland Harbor, which is a limited, confined area of any given stock's
home range;
<bullet> Monitoring reports from similar work have documented
little to no observable effect on individuals of the same species
impacted by the specified activities;
<bullet> The required mitigation measures (i.e., soft starts, pre-
clearance monitoring, shutdown zones, bubble curtains) are expected to
be effective in reducing the effects of the specified activity by
minimizing the numbers of marine mammals exposed to injurious levels of
sound and by ensuring that any take by Level A harassment is, at most,
a small degree of AUD INJ and of a lower degree that would not impact
the fitness of any animals; and
<bullet> The intensity of anticipated takes by Level B harassment
is low for all stocks consisting of, at worst, temporary modifications
in behavior, and would not be of a duration or intensity expected to
result in impacts on reproduction or survival.
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, and taking into
consideration the implementation of the required monitoring and
mitigation measures, NMFS finds that the total marine mammal take from
the planned specified activity would have a negligible impact on all
affected marine mammal species or stocks.
Small Numbers
As noted previously, only take of small numbers of marine mammals
may be authorized under section 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 maximum number of individuals
taken in any year 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. When the
predicted maximum annual number of individuals to be taken is fewer
than one-third of the species or stock abundance, the take is
considered to be of small numbers (see 86 FR 5322, January 19, 2021).
Additionally, other qualitative factors may be considered in the
analysis, such as the temporal or spatial scale of the activities.
As in the proposed rule, the maximum annual amount of take allowed
under the final rule is less than one-third of the population abundance
estimates for all stocks (table 5). The numbers of animals authorized
to be taken are small relative to the relevant species or stock
abundances even if each estimated take occurred to a new individual,
and even if all take accrued to a single stock.
Given there is no substantive change to the small numbers analysis
described in the proposed rule, it is herein incorporated by reference.
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 finds that small numbers of
marine mammals would 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
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.
Adaptive Management
The regulations governing the take of marine mammals incidental to
IBRP's proposed construction activities would contain an adaptive
management component.
The reporting requirements associated with this final rule are
designed to provide NMFS with monitoring data from the previous year to
allow consideration of whether any changes are appropriate. The use of
adaptive management allows NMFS to consider new information from
different sources to determine (with input from IBRP regarding
practicability) on an annual basis if mitigation or monitoring measures
should be modified (including additions or deletions). Mitigation or
monitoring measures could be modified if new data suggests that such
modifications would have a reasonable likelihood more effectively
achieving the goals of the mitigation and monitoring and if the
measures are practicable.
The following are examples of the possible sources of applicable
data to be considered through the adaptive management process: (1)
results from monitoring reports, as required by MMPA authorizations;
(2) results from general marine mammal and sound research; and (3) any
information which reveals that marine mammals may have been taken in a
manner, extent, or number not authorized by these regulations or
subsequent LOA.
Endangered Species Act
Section 7(a)(2) of the ESA of 1973 (16 U.S.C. 1531 et seq.)
requires that each Federal agency ensure 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 with its issuance of ITAs, NMFS consults
internally whenever we propose to authorize take for endangered or
threatened species, in this case with the NMFS West Coast Regional
Office.
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.
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., promulgation of regulations
and subsequent issuance of an LOA thereunder) with respect to potential
impacts on the human environment.
This action is consistent with categories of activities identified
in Categorical Exclusion B4 (ITAs with no anticipated serious injury or
mortality) of the Companion Manual for NAO 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
[[Page 28455]]
circumstances that would preclude this categorical exclusion.
Accordingly, NMFS has determined that the issuance of the incidental
take regulations and LOA qualifies to be categorically excluded from
further NEPA review.
Promulgation
As a result of these determinations, NMFS is promulgating these
regulations that: (1) allow for take of three marine mammal species,
comprising three stocks, by Level A and Level B harassment, incidental
to construction activities associated with the IBR Project for a 5-year
period from September 15, 2027, through September 14, 2032; and (2)
prescribe mitigation, monitoring and reporting measures.
Classification
Executive Order 12866
The Office of Management and Budget determined that this final rule
is not significant for purposes of Executive Order (E.O.) 12866.
Executive Order 14192
This final rule is not an E.O. 14192 regulatory action because this
action is not significant under E.O. 12866.
Regulatory Flexibility Act (RFA)
Pursuant to section 605(b) of the Regulatory Flexibility Act (5
U.S.C. 601 et seq.), the Chief Counsel for Regulation of the Department
of Commerce has certified to the Chief Counsel for Advocacy of the
Small Business Administration during the proposed rule stage that this
action would not have a significant economic impact on a substantial
number of small entities. The IBRP is a bi-state governmental program
focused on improving the transit corridor between Washington and
Oregon. The IBRP is the sole entity that would be subject to the
requirements of this final rule, and the IBRP is not a small
governmental jurisdiction, small organization, or small business, as
defined by the RFA, because it is a department of the two state
governments. Because of this certification, a final regulatory
flexibility analysis is not required and none has been prepared.
Paperwork Reduction Act (PRA)
This final rule contains a collection-of-information requirement
subject to the provisions of the PRA. Notwithstanding any other
provision of law, no person is required to respond to nor shall a
person be subject to a penalty for failure to comply with a collection
of information subject to the requirements of the PRA unless that
collection of information displays a currently valid OMB control
number. These requirements have been approved by OMB under control
number 0648-0151 and include applications for regulations, subsequent
LOAs, and reports.
List of Subjects in 50 CFR Part 217
Acoustics, Administrative practice and procedure, Construction,
Marine mammals, Mitigation and monitoring requirements, Reporting
requirements, Wildlife.
Dated: May 13, 2026.
Samuel D. Rauch III,
Deputy Assistant Administrator for Regulatory Programs, National Marine
Fisheries Service.
For the reasons set forth in the preamble, NMFS amends 50 CFR part
217 as follows:
PART 217--REGULATIONS GOVERNING THE TAKE OF MARINE MAMMALS
INCIDENTAL TO SPECIFIED ACTIVITIES
0
1. The authority citation for part 217 continues to read as follows:
Authority: 16 U.S.C. 1361 et seq., unless otherwise noted.
0
2. Add Subpart O, consisting of Sec. Sec. 217.141 through 217.149, to
read as follows:
Subpart O--Taking Marine Mammals Incidental to the Interstate Bridge
Replacement Project on Interstate 5 between Portland, OR, and
Vancouver, WA
Sec.
217.141 Specified activity and specified geographical region.
217.142 Effective dates.
217.143 Permissible methods of taking.
217.144 Prohibitions.
217.145 Mitigation requirements.
217.146 Requirements for monitoring and reporting.
217.147 Letters of Authorization.
217.148 Modifications of Letters of Authorization.
217.149 [Reserved]
Subpart O--Taking Marine Mammals Incidental to the Interstate
Bridge Replacement Project on Interstate 5 between Portland, OR,
and Vancouver, WA
Sec. 217.141 Specified activity and specified geographical region.
(a) The incidental taking of marine mammals by the Interstate
Bridge Replacement Program (IBRP) may be authorized in a letter of
authorization (LOA) only if it occurs at or around the Interstate 5
bridges over the Columbia River and North Portland Harbor between
Portland, OR, and Vancouver, WA, incidental to the specified activities
outlined in paragraph (b) of this section. Requirements imposed on the
IBRP in this subpart must be implemented by those persons it authorizes
or funds to conduct activities on its behalf.
(b) The specified activities are construction and demolition
activities associated with the Interstate Bridge Replacement Project
between Portland, OR, and Vancouver, WA.
Sec. 217.142 Effective dates.
Regulations in this subpart are effective from September 15, 2027,
until September 14, 2032.
Sec. 217.143 Permissible methods of taking.
Under a LOA issued pursuant to Sec. 216.106 of this chapter and
this subpart, the IBRP and those persons it authorizes or funds to
conduct activities on its behalf may incidentally, but not
intentionally, take marine mammals within the specified geographical
region by harassment associated with the specified activities provided
they are in compliance with all terms, conditions, and requirements of
the regulations in this subpart and the applicable LOA.
Sec. 217.144 Prohibitions.
(a) Except for the takings permitted in Sec. 217.143 and
authorized by a LOA issued under Sec. 216.106 of this chapter and this
subpart, it is unlawful for any person to do any of the following in
connection with the specified activities:
(1) Violate or fail to comply with the terms, conditions, and
requirements of this subpart or a LOA issued under this subpart;
(2) Take any marine mammal not specified in such LOA;
(3) Take any marine mammal specified in such LOA in any manner
other than as specified;
(4) Take a marine mammal specified in such LOA after NMFS
determines such taking results in more than a negligible impact on the
species or stocks of such marine mammal; or
(5) Take a marine mammal specified in such LOA after NMFS
determines such taking results in an unmitigable adverse impact on the
species or stock of such marine mammal for taking for subsistence uses.
(b) [Reserved]
Sec. 217.145 Mitigation requirements.
(a) When conducting the specified activities identified in Sec.
217.141(b), IBRP must implement the mitigation measures contained in
this section and any LOA issued under Sec. 216.106 of this chapter and
this subpart. These mitigation measures include, but are not limited
to:
(1) A copy of any issued LOA must be in the possession of the IBRP,
its
[[Page 28456]]
designees, and work crew personnel operating under the authority of the
issued LOA;
(2) The IBRP must ensure that construction supervisors and crews,
the monitoring team and relevant IBRP staff are trained prior to the
start of all pile driving so that responsibilities, communication
procedures, monitoring protocols, and operational procedures are
clearly understood. New personnel joining during the project must be
trained prior to commencing work; and
(3) The IBRP, construction supervisors and crews, Protected Species
Observers (PSOs), and relevant IBRP staff must prevent direct physical
interaction with marine mammals during construction activity. If a
marine mammal comes within 10 m of such activity, operations must cease
and vessels must reduce speed to the minimum level required to maintain
steerage and safe working conditions, as necessary to prevent direct
physical interaction;
(4) The IBRP must employ PSOs and establish monitoring locations
pursuant to Sec. 217.146 and as described in a NMFS-approved Marine
Mammal Monitoring and Mitigation Plan;
(i) For all pile driving activities, land-based PSOs must be
stationed at the best vantage points practicable to monitor for marine
mammals and implement shutdown/delay procedures. A minimum of two
locations must be used to monitor the harassment zones specified in any
LOA issued under Sec. 216.106 of this chapter to the maximum extent
possible based on positioning and daily visibility conditions. PSOs
must be able to implement shutdown or delay procedures when applicable
through communication with the equipment operator;
(ii) [Reserved];
(5) Pre-start clearance monitoring must take place from 30 minutes
prior to initiation of pile driving activity (i.e., pre-start clearance
monitoring) through 30 minutes post-completion of pile driving
activity;
(i) Pre-start clearance monitoring must be conducted during periods
of visibility sufficient for the lead PSO to determine that the
shutdown zones are clear of marine mammals;
(ii) Pile driving may commence only if, following 30 minutes of
observation, it is determined by the lead PSO that the shutdown zones
are clear of marine mammals;
(6) For all pile driving activity, the IBRP must implement shutdown
zones with radial distances as identified in a LOA issued under Sec.
216.106 of this chapter;
(i) If a marine mammal is observed entering or within the shutdown
zone, all pile driving activities, including soft starts, at that
location must be halted. If pile driving is halted or delayed due to
the presence of a marine mammal, the activity may not commence or
resume until either the animal has voluntarily left and has been
visually confirmed beyond the shutdown zone or 15 minutes have passed
without re-detection of the animal;
(ii) In the event of a delay or shutdown of activity resulting from
marine mammals in the shutdown zone, animal behavior must be monitored
and documented;
(iii) If work ceases for more than 30 minutes, the shutdown zones
must be cleared again for 30 minutes prior to reinitiating pile
driving;
(7) The IBRP must use soft start techniques when impact pile
driving. Soft start requires the IBRP to conduct three sets of strikes
(three strikes per set) at reduced hammer energy with a 30-second
waiting period between each set. A soft start must 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 30 minutes or longer;
(8) The IBRP must use bubble curtains for impact pile driving in
waters deeper than 0.67 m, except when necessary for testing of bubble
curtain effectiveness during hydroacoustic monitoring. The bubble
curtain must be operated to achieve optimal performance. At a minimum,
the bubble curtain must comply with the following:
(i) The bubble curtain must distribute air bubbles around 100
percent of the piling perimeter for the full depth of the water column;
(ii) The lowest bubble ring must be in contact with the mudline
and/or rock bottom for the full circumference of the ring, and the
weights attached to the bottom ring shall ensure 100 percent mudline
and/or rock bottom contact. No parts of the ring or other objects shall
prevent full mudline and/or rock bottom contact;
(iii) Air flow to the bubblers must be balanced around the
circumference of the pile;
(9) Pile driving activity must be halted upon observation of a
species entering or within the harassment zone for either a species for
which incidental take is not authorized or a species for which
incidental take has been authorized but the authorized number of takes
has been met;
(b) [Reserved]
Sec. 217.146 Requirements for monitoring and reporting.
(a) The IBRP must submit a marine mammal monitoring plan to NMFS
for approval at least 90 days before the start of construction and
abide by the approved plan.
(b) The IBRP must submit a hydroacoustic monitoring plan to NMFS
for approval at least 60 days before the start of impact pile driving
and abide by the approved plan.
(c) Monitoring must be conducted by qualified, NMFS-approved PSOs,
in accordance with the following conditions:
(1) PSOs must be independent of the activity contractor (e.g.,
employed by a subcontractor) and have no other assigned tasks during
monitoring duties;
(2) PSOs must be approved by NMFS prior to beginning work on the
specified activities;
(3) PSOs must be trained in marine mammal identification and
behavior;
(i) A designated project lead PSO must be on site when more than
two PSOs are on duty. The project lead PSO must have prior experience
performing the duties of a PSO during in-water construction activities
pursuant to a NMFS-issued ITA or letter of concurrence;
(ii) Other PSOs may substitute other relevant experience, education
(degree in biological science or related field), or training for prior
experience performing the duties of a PSO during construction activity
pursuant to a NMFS-issued incidental take authorization;
(d) The IBRP must submit a draft annual summary monitoring report
on all marine mammal monitoring conducted during each construction
season which includes final electronic data sheets in a searchable
format within 90 calendar days after the completion of each
construction season or 60 days prior to a requested date of issuance of
any future incidental take authorization for projects at the same
location, whichever comes first. A draft comprehensive 5-year summary
report must also be submitted to NMFS within 90 days of the end of year
5 of the project. The reports must detail the monitoring protocol and
summarize the data recorded during monitoring. If no comments are
received from NMFS within 30 days of receipt of the draft report, the
report may be considered final. If comments are received, a final
report addressing NMFS comments must be submitted within 30 days after
receipt. At a minimum, the reports must contain:
(1) Dates and times (begin and end) of all marine mammal
monitoring;
[[Page 28457]]
(2) Construction activities occurring during each daily observation
period, including how many and what type of piles were driven or
removed, by what method (i.e., impact or vibratory), the total duration
of driving time for each pile (vibratory driving), and number of
strikes for each pile (impact driving);
(3) Environmental conditions during monitoring periods (at
beginning and end of PSO shift and whenever conditions change
significantly), Beaufort sea state, and any other relevant weather
conditions including cloud cover, fog, sun glare, and overall
visibility to the horizon, and estimated observable distance (if less
than the harassment zone distance);
(4) Upon observation of a marine mammal, the following information
must be collected:
(i) Name of the PSO who sighted the animal, observer location, and
activity at time of sighting;
(ii) Time of sighting;
(iii) Identification of the animal (e.g., genus/species, lowest
possible taxonomic level, or unidentified), PSO confidence in
identification, and the composition of the group if there is a mix of
species;
(iv) Distances and bearings of each marine mammal observed in
relation to the pile being driven for each sighting (if pile driving
was occurring at time of sighting);
(v) Estimated number of animals (min/max/best);
(vi) Estimated number of animals by cohort (adults, juveniles,
neonates, group composition, etc.);
(vii) Animal's closest point of approach and estimated time spent
within the harassment zone;
(viii) Description of any marine mammal behavioral observations
(e.g., observed behaviors such as feeding or traveling), including an
assessment of behavioral responses to the activity (e.g., no response
or changes in behavioral state such as ceasing feeding, changing
direction, flushing, or breaching);
(ix) Number of marine mammals detected within the harassment zones,
by species;
(x) Detailed information about any implementation of any mitigation
(e.g., shutdowns and delays), a description of specific actions that
ensued, and resulting changes in the behavior of the animal, if any;
and
(xi) All PSO data in an electronic format that can be queried such
as a spreadsheet or database (i.e., digital images of data sheets are
not sufficient).
(e) Acoustic monitoring reports must be submitted on the same
schedule as visual monitoring reports (i.e., within 90 days following
the completion of construction). The acoustic monitoring report must
contain the informational elements described in the acoustic monitoring
plan and, at minimum, must include:
(1) Hydrophone equipment and methods: recording device, sampling
rate, calibration details, distance (m) from the pile where recordings
were made; and the depth of water and recording device(s);
(2) Location, identifier, orientation (e.g., vertical, battered),
material, and geometry (shape, diameter, thickness, length) of pile
being driven, substrate type, method of driving during recordings
(e.g., hammer model and energy), and total pile driving duration;
(3) Whether a sound attenuation device is used and, if so, a
detailed description of the device used, its distance from the pile and
hydrophone, and the duration of its use per pile;
(4) For impact pile driving: number of strikes per day and per pile
and strike rate; depth of substrate to penetrate; decidecade (one-third
octave) band spectra in tabular and figure formats computed on a per-
pulse basis, including the arithmetic mean or median for all computed
spectra; and pulse duration and median, mean, maximum, minimum, and
number of samples (where relevant) of the following sound level
metrics: RMS SPL; SEL<INF>24</INF>; peak (PK) SPL; and
SEL<INF>ss</INF>.
(f) In the event that personnel involved in the construction
activities discover an injured or dead marine mammal, the IBRP must
report the incident to NMFS Office of Protected Resources (OPR) and to
the West Coast Regional Stranding Coordinator no later than 24 hours
after the initial observation. If the death or injury was caused by the
specified activity, the IBRP must immediately cease the specified
activities described in Sec. 217.141(b) until NMFS OPR is able to
review the circumstances of the incident. The IBRP must not resume
their activities until notified by NMFS. The report must include the
following information:
(1) Time, date, and location (latitude/longitude) of the first
discovery (and updated location information if known and applicable);
(2) Species identification (if known) or description of the
animal(s) involved;
(3) Condition of the animal(s) (including carcass condition if the
animal is dead);
(4) Observed behaviors of the animal(s), if alive;
(5) If available, photographs or video footage of the animal(s);
and
(6) General circumstances under which the animal was discovered.
Sec. 217.147 Letters of Authorization.
(a) To incidentally take marine mammals pursuant to these
regulations, the IBRP must apply for and obtain an LOA.
(b) An LOA, unless suspended or revoked, may be effective for a
period of time not to exceed the effective dates of this subpart.
(c) In the event of projected changes to the activity or to
mitigation and monitoring measures required by an LOA, the IBRP must
apply for and obtain a modification of the LOA as described in Sec.
217.148.
(d) The LOA must set forth the following information:
(1) Permissible methods of incidental taking;
(2) Means of effecting the least practicable adverse impact (i.e.,
mitigation) on the species, its habitat, and on the availability of the
species for subsistence uses; and
(3) Requirements for monitoring and reporting.
(e) Issuance of the LOA must be based on a determination that the
level of taking will be consistent with the findings made for the total
taking allowable under this subpart.
(f) Notice of issuance or denial of an LOA must be published in the
Federal Register within 30 days of a determination.
Sec. 217.148 Modifications of Letters of Authorization.
(a) A LOA issued under Sec. Sec. 216.106 of this chapter and
217.147 for the specified activities may be modified upon request by
the IBRP, provided that:
(1) The specified activity and mitigation, monitoring, and
reporting measures, as well as the anticipated impacts, are the same as
those described and analyzed for this subpart; and
(2) NMFS determines that the mitigation, monitoring, and reporting
measures required by the previous LOA were implemented.
(b) For LOA modification by the IBRP that includes changes to the
specified activity or the mitigation, monitoring, or reporting measures
that do not change the findings made for the regulations in this
subpart or result in no more than a minor change in the total estimated
number of takes (or distribution by species or years), NMFS may publish
a notice of proposed LOA in the Federal Register, including the
associated analysis of the change and solicit public comment before
issuing the LOA.
(c) A LOA issued under Sec. 216.106 of this chapter and Sec.
217.147 for the specified activity may be modified by NMFS under the
following circumstances:
[[Page 28458]]
(1) NMFS may modify the existing mitigation, monitoring, or
reporting measures, after consulting with the IBRP regarding the
practicability of the modifications, if doing so creates a reasonable
likelihood of more effectively accomplishing the goals of the
mitigation and monitoring measures;
(i) Possible sources of data that could contribute to the decision
to modify the mitigation, monitoring, or reporting measures in an LOA
include, but are not limited to:
(A) Results from the IBRP's monitoring;
(B) Results from other marine mammal and/or sound research or
studies; and
(C) Any information that reveals marine mammals may have been taken
in a manner, extent or number not authorized by this subpart or
subsequent LOAs; and
(ii) If, through adaptive management, the modifications to the
mitigation, monitoring, or reporting measures are substantial, NMFS
shall publish a notice of proposed LOA in the Federal Register and
solicit public comment;
(2) If NMFS determines that an emergency exists that poses a
significant risk to the well-being of the species or stocks of marine
mammals specified in a LOA issued pursuant to Sec. Sec. 216.106 of
this chapter and 217.147, a LOA may be modified without prior notice or
opportunity for public comment. Notification will be published in the
Federal Register within 30 days of the action.
Sec. 217.149 [Reserved]
[FR Doc. 2026-09884 Filed 5-15-26; 8:45 am]
BILLING CODE 3510-22-P
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