89 FR 152 pgs. 64420-64432 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Weyerhaeuser Company for Their Log Export Dock Project on the Columbia River Near Longview, Washington
Type: NOTICEVolume: 89Number: 152Pages: 64420 - 64432
Pages: 64420, 64421, 64422, 64423, 64424, 64425, 64426, 64427, 64428, 64429, 64430, 64431, 64432Docket number: [RTID 0648-XE088]
FR document: [FR Doc. 2024-17470 Filed 8-6-24; 8:45 am]
Agency: Commerce Department
Sub Agency: National Oceanic and Atmospheric Administration
Official PDF Version: PDF Version
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
[RTID 0648-XE088]
Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Weyerhaeuser Company for Their Log Export Dock Project on the Columbia River Near Longview, Washington
AGENCY:
National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce.
ACTION:
Notice; issuance of an incidental harassment authorization.
SUMMARY:
In accordance with the regulations implementing the Marine Mammal Protection Act (MMPA) as amended, notification is hereby given that NMFS has issued an incidental harassment authorization (IHA) to Weyerhaeuser Company (Weyerhaeuser) to incidentally harass marine mammals during construction activities associated with the Log Export Dock Project on the Columbia River near Longview, Washington.
DATES:
This authorization is effective from September 1, 2025 through August 31, 2026.
ADDRESSES:
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 below.
FOR FURTHER INFORMATION CONTACT:
Rachel Wachtendonk, Office of Protected Resources (OPR), 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 (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 proposed or, if the taking is limited to harassment, a notice of a proposed IHA is provided to the public for review.
Authorization for incidental takings shall be granted if NMFS finds that the taking will have a negligible impact on the species or stock(s) 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 the species or stocks for taking for certain subsistence uses (referred to in shorthand as "mitigation"); and requirements pertaining to the monitoring and reporting of the takings. The definitions of all applicable MMPA statutory terms cited above are included in the relevant sections below.
Summary of Request
[top] On October 29, 2023, NMFS received a request from Weyerhaeuser for an IHA to take marine mammals incidental to pile driving and removal activities associated with the Log Export Dock
Description of the Specified Activity
Overview
Weyerhaeuser is planning the partial demolition and replacement of the existing Log Export dock on the Columbia River, near Longview, Washington. The project includes impact and vibratory pile installation and vibratory pile removal. Vibratory and impact pile driving are expected to start in September 2025 and take about 120 days of in-water work within the U.S. Army Corps of Engineers (USACE) and the U.S. Fish and Wildlife Service (USFWS)-designated in-water work window (September 1, 2025-January 3, 2026). All pile installation will occur during the work window, which would minimize potential exposure of Endangered Species Act (ESA) listed fish species from impact pile driving. An additional 30 days of vibratory pile removal may occur outside the window.
The demolition and replacement of the 612-foot (ft), or 186.5-meter (m) berth A of the Log Export Dock would include the removal of 983 16-inch (in), or 0.41-m, timber piles, 36 16-in (0.41-m) steel pipe piles, 10 12-in (0.30-m) steel H-piles, 7 12-in (0.30-m) steel pipe piles, and 20 14- or 16-in (0.36- or 0.41-m) steel fender piles. Existing piles would be primarily removed by the deadpull method, with piles being removed with the vibratory hammer if the deadpull is unsuccessful. Broken or damaged piles would be cut at the mudline. It is anticipated that 75 percent of the existing 983 timber piles will be removed by the deadpull method, with the remaining 246 being removed with the vibratory hammer. The new structure will be supported by the installation of 325 30-in (0.76-m) steel pipe piles. In addition, up to 26 24-in (0.61 m) temporary steel pipe piles may be installed and removed to support permanent pile installation. Temporary and permanent piles would be initially installed with a vibratory hammer, with permanent piles being followed by an impact hammer to embed them to their final depth. To reduce underwater noise produced by impact pile driving, an unconfined bubble curtain will be used during impact pile installation.
In order to maintain project schedules, it is possible that multiple pieces of equipment would operate at the same time within the project area. Piles may be driven on the same day or, less commonly, at the same time, by two impact hammers, one impact hammer and one vibratory hammer, or two vibratory hammers. The method of installation, and whether concurrent pile driving scenarios will be implemented, will be determined by the construction crew once the project has begun. Therefore, the total take estimate reflects the worst-case scenario (both hammers installing 30-in steel pipe piles) for the proposed project. However, the most likely scenario is the vibratory removal of a 16-in timber pile at the same time as installing a 30-in steel pipe piles by vibratory or impact methods.
A detailed description of the planned construction project is provided in the Federal Register notice for the proposed IHA (89 FR 48579, June 7, 2024). Since that time, no changes have been made to the planned activities. Therefore, a detailed description is not provided here. Please refer to that Federal Register notice for the description of the specific activity.
Comments and Responses
A notice of NMFS' proposal to issue an IHA to Weyerhaeuser was published in the Federal Register on June 7, 2024 (89 FR 48579). That notice described, in detail, Weyerhaeuser's activity, the marine mammal species that may be affected by the activity, and the anticipated effects on marine mammals. In that notice, we requested public input on the request for authorization described therein, our analyses, the proposed authorization, and any other aspect of the notice of proposed IHA, and requested that interested persons submit relevant information, suggestions, and comments. During the 30-day public comment period, NMFS did not receive any substantive comments on the proposed IHA.
Changes From the Proposed IHA to Final IHA
In table 5 of the proposed IHA Federal Register notice (89 FR 48579, June 7, 2024) the source levels for the impact driving of the 30-in steel pipe piles did not include the 5 decibel (dB) reduction from the bubble curtain. These values have been corrected in tables 4 and 5 of this notice. The 5 dB reduction resulted in smaller Level A and Level B isopleths, which have been corrected in table 7 of this notice. The estimated number of takes by Level B harassment remains the same for all species because the smaller Level B isopleth still spans the width of the river and the same number of marine mammals are expected to be transiting through the project area. The estimated number of takes by Level A harassment for harbor seals was reduced to 56 to account for the smaller Level A isopleth which no longer spans the full width of the river. These values have been corrected in table 8 of this notice. Finally the smaller isopleths from the 5 dB reduction also decreased the minimum shutdown zone and harassment monitoring zone for impact pile driving. The reduced shutdown and monitoring zones have been corrected in table 9 of this notice.
Description of Marine Mammals in the Area of Specified Activities
Sections 3 and 4 of Weyerhaeuser's application summarize available information regarding status and trends, distribution and habitat preferences, and behavior and life history of the potentially affected species. NMFS fully considered all of this information, and we refer the reader to these descriptions, instead of reprinting the information. Additional information regarding population trends and threats may be found in NMFS' 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' website ( https://www.fisheries.noaa.gov/find-species ).
[top] Table 1 lists all species or stocks for which take is expected and authorized for this activity and summarizes information related to the population or stock, including regulatory status under the MMPA and ESA and potential biological removal (PBR), where known. 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' SARs). While no serious injury or mortality is anticipated or authorized here, PBR and annual serious injury and mortality from anthropogenic sources are included here as gross indicators of
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' 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. All managed stocks in this region are assessed in NMFS' U.S. 2022 SARs. All values presented in table 1 are the most recent available at the time of publication (including from the draft 2023 SARs) and are available online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments.
| Common name | Scientific name | Stock | ESA/ MMPA status; strategic (Y/N)? 2 | Stock abundance (CV, N min , most recent abundance survey)? 3 | PBR | Annual M/SI? 4 |
|---|---|---|---|---|---|---|
| Order Carnivora-Pinnipedia | ||||||
| Family Otariidae (eared seals and sea lions) | ||||||
| California Sea Lion | Zalophus californianus | U.S | -, -, N | 257,606 (N/A, 233,515, 2014) | 14,011 | >321 |
| Steller Sea Lion | Eumetopias jubatus | Eastern | -, -, N | 36,308 (N/A, 36,308, 2022)? 5 | 2,178 | 93.2 |
| Family Phocidae (earless seals): | ||||||
| Harbor Seal | Phoca vitulina | OR/WA Coastal | -, -, N | UNK (UNK, UNK, 1999) | UND | 10.6 |
| 1 ?Information on the classification of marine mammal species can be found on the web page for The Society for Marine Mammalogy's Committee on Taxonomy ( https://marinemammalscience.org/science-and-publications/list-marine-mammal-species-subspecies; Committee on Taxonomy, 2022). | ||||||
| 2 ?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. | ||||||
| 3 ?NMFS marine mammal SARs online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region. CV is coefficient of variation; N min is the minimum estimate of stock abundance. In some cases, CV is not applicable. | ||||||
| 4 ?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 mortality and serious injury (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. | ||||||
| 5 ?Nest is best estimate of counts, which have not been corrected for animals at sea during abundance surveys. Estimates provided are for the U.S. only. | ||||||
As indicated above, all three species (with three managed stocks) in table 2 temporally and spatially co-occur with the activity to the degree that take is reasonably likely to occur.
A detailed description of the species likely to be affected by Weyerhaeuser's project, including brief introductions to the species and relevant stocks as well as available information regarding population trends and threats, and information regarding local occurrence, were provided in the Federal Register notice for the proposed IHA (89 (FR 48579, June 7, 2024); since that time, we are not aware of any changes in the status of these species and stocks; therefore, detailed descriptions are not provided here. Please refer to that Federal Register notice for these descriptions. Please also refer to NMFS' website ( https://www.fisheries.noaa.gov/find-species ) for generalized species accounts.
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. 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, 2019) recommended that marine mammals be divided into hearing groups based on directly measured (behavioral or auditory evoked potential techniques) or estimated hearing ranges (behavioral response data, anatomical modeling, etc. ). 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 2.
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| Hearing group | Generalized hearing range in hertz (Hz) and kilohertz (kHz)?* |
|---|---|
| Low-frequency (LF) cetaceans (baleen whales) | 7 Hz to 35 kHz. |
| Mid-frequency (MF) cetaceans (dolphins, toothed whales, beaked whales, bottlenose whales) | 150 Hz to 160 kHz. |
| High-frequency (HF) cetaceans (true porpoises, Kogia spp., river dolphins, Cephalorhynchids, Lagenorhynchus cruciger & L. australis ) | 275 Hz to 160 kHz. |
| Phocid pinnipeds (PW) (underwater) (true seals) | 50 Hz to 86 kHz. |
| Otariid pinnipeds (OW) (underwater) (sea lions and fur seals) | 60 Hz to 39 kHz. |
| *?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 the ~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 (Hemilä et al., 2006; Kastelein et al., 2009; Reichmuth et al., 2013). This division between phocid and otariid pinnipeds is now reflected in the updated hearing groups proposed in Southall et al. (2019).
For more detail concerning these groups and associated frequency ranges, see NMFS (2018) for a review of available information.
Potential Effects of Specified Activities on Marine Mammals and Their Habitat
The effects of underwater noise from Weyerhaeuser's pile driving activities have the potential to result in behavioral harassment of marine mammals in the vicinity of the project area. The notice of the proposed IHA (FR 48579, June 7, 2024) included a discussion of the effects of anthropogenic noise on marine mammals and the potential effects of underwater noise from Weyerhaeuser's pile driving activities on marine mammals and their habitat. That information and analysis is incorporated by reference into this final IHA determination and is not repeated here; please refer to the notice of the proposed IHA (FR 48579, June 7, 2024).
Estimated Take of Marine Mammals
This section provides an estimate of the number of incidental takes authorized through the IHA, which will inform NMFS' consideration of "small numbers," the negligible impact determinations, and impacts on subsistence uses.
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 will primarily be by Level B harassment, as use of the acoustic source ( i.e., pile driving) 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 result, primarily for phocids because predicted auditory injury zones are larger than for otariids. Auditory injury is unlikely to occur for otariids. The proposed mitigation and monitoring measures are expected to minimize the severity of the taking to the extent practicable.
As described previously, no serious injury or mortality is anticipated or authorized for this activity. Here we describe how the information provided above is synthesized to produce a quantitative estimate of the take that is reasonably likely to occur and is authorized.
For acoustic impacts, 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) the number of days of activities. We note that while these factors can contribute to a basic calculation to provide an initial prediction of potential 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 authorized take numbers.
Acoustic Thresholds
NMFS recommends the use of 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 permeant threshold shift (PTS) of some degree (equated to Level A harassment).
[top] Level B Harassment -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 or exposure context ( e.g., frequency, predictability, duty cycle, duration of the exposure, signal-to-noise ratio, distance to the source), the environment ( e.g., bathymetry, other noises in the area, predators in the area), and the receiving animals (hearing, motivation, experience, demography, life stage, depth) and can be difficult to predict ( e.g., Southall et al., 2007, 2021; Ellison et al., 2012). Based on what the available science indicates and the practical need to use a threshold based on a metric that is both predictable and measurable for most activities, NMFS typically uses a generalized acoustic threshold based on received level to estimate the onset of behavioral harassment. NMFS generally predicts that marine mammals are likely to be behaviorally harassed in a manner considered to be Level B harassment when exposed to underwater anthropogenic noise above root-mean-squared pressure received levels (RMS SPL) of 120 dB (referenced to 1 micropascal (re 1 µPa)) for continuous ( e.g., vibratory pile driving, drilling) and above RMS SPL 160 dB re 1 µPa for non-explosive impulsive ( e.g., seismic airguns) or intermittent ( e.g., scientific sonar) sources. Generally speaking, Level B harassment take estimates based on these behavioral harassment thresholds are expected to include any likely takes by temporary threshold shift (TTS) as, in most cases, the likelihood of TTS occurs at distances from the source less than those at which behavioral harassment is likely. TTS of a sufficient degree can manifest as behavioral harassment, as reduced hearing sensitivity and the potential reduced opportunities to detect important signals (conspecific communication, predators, prey) may
Weyerhaeuser's activity includes the use of continuous (vibratory pile driving) and impulsive (impact pile driving) sources, and therefore the RMS SPL thresholds of 120 and 160 dB re 1µPa are applicable.
Level A harassment -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). Weyerhaeuser's activity includes the use of impulsive (impact pile driving) and non-impulsive (vibratory pile driving) 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.
| Hearing group | PTS onset acoustic thresholds? * (received level) | Impulsive | Non-impulsive |
|---|---|---|---|
| Low-Frequency (LF) Cetaceans | Cell 1: L pk,flat : 219 dB L E,LF,24h : 183 dB | Cell 2: L E,LF,24h : 199 dB. | |
| Mid-Frequency (MF) Cetaceans | Cell 3: L pk,flat : 230 dB L E,MF,24h : 185 dB | Cell 4: L E,MF,24h : 198 dB. | |
| High-Frequency (HF) Cetaceans | Cell 5: L pk,flat : 202 dB L E,HF,24h : 155 dB | Cell 6: L E,HF,24h : 173 dB. | |
| Phocid Pinnipeds (PW) (Underwater) | Cell 7: L pk,flat : 218 dB L E,PW,24h : 185 dB | Cell 8: L E,PW,24h : 201 dB. | |
| Otariid Pinnipeds (OW) (Underwater) | Cell 9: L pk,flat : 232 dB L E,OW,24h : 203 dB | Cell 10: L E,OW,24h : 219 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 ( L pk ) has a reference value of 1 µPa, and cumulative sound exposure level ( L E ) has a reference value of 1µPa 2 s. In this table, thresholds are abbreviated to reflect American National Standards Institute (ANSI) 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 are used in estimating the area ensonified above the acoustic thresholds, including 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. Pile driving generates underwater noise that can potentially result in disturbance to marine mammals in the project area. The maximum (underwater) area ensonified is determined by the topography of the Columbia River, including intersecting land masses that will reduce the overall area of potential impact. Additionally, vessel traffic, including the other half of the dock (berth B) remaining operational during construction, in the project area may contribute to elevated background noise levels, which may mask sounds produced by the project.
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 × Log 10 ( R 1 / R 2 ),
Where
TL = transmission loss in dB;
B = transmission loss coefficient; for practical spreading equals 15;
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.
This formula neglects loss due to scattering and absorption, which is assumed to be zero here. The degree to which underwater sound propagates away from a sound source is dependent on a variety of factors, most notably the water bathymetry and presence or absence of reflective or absorptive conditions including in-water structures and sediments. Spherical spreading occurs in a perfectly unobstructed (free-field) environment not limited by depth or water surface, resulting in a 6-dB reduction in sound level for each doubling of distance from the source (20 × log 10 [range]). Cylindrical spreading occurs in an environment in which sound propagation is bounded by the water surface and sea bottom, resulting in a reduction of 3 dB in sound level for each doubling of distance from the source (10 × log 10 [range]). A practical spreading value of 15 is often used under conditions, such as the project site, where water increases with depth as the receiver moves away from the shoreline, resulting in an expected propagation environment that would lie between spherical and cylindrical spreading loss conditions. Practical spreading loss is assumed here.
[top] The intensity of pile driving sounds is greatly influenced by factors such as the type of piles, hammers, and the physical environment in which the activity takes place. In order to calculate the distances to the Level A harassment and the Level B harassment sound thresholds for the methods and piles being used in this project, NMFS used acoustic monitoring data from other locations to develop proxy source levels for the various pile types, sizes and methods (table 4). Generally, we choose source levels from similar pile types from locations ( e.g., geology, bathymetry) similar to the project.
| Pile type and size | Peak SPL (re 1 µPa) | RMS SPL (re 1 µPa) | SEL (re 1 µPa 2 -s ) | Source |
|---|---|---|---|---|
| Vibratory pile installation and removal | ||||
| 16-in timber pile | 162 | Caltrans, 2020. | ||
| 12-in steel pipe | 158 | Laughlin, 2012. | ||
| 12-in steel H-pile | 152 | Laughlin, 2019. | ||
| 16-in steel pipe? 1 | 161 | Navy, 2015. | ||
| 24-in temporary steel pipe | 161 | Navy, 2015. | ||
| 30-in steel pipe | 163 | Anchor, QEA, 2021; Greenbush, 2019; Denes et al., 2016, table 72. | ||
| Impact pile installation | ||||
| 30-in steel pipe? 2 | 210 (205) | 190 (185) | 177 (177) | Caltrans, 2020. |
| 1 ?For the purposes of this analysis, the underwater sound source level for removal of existing 16-in steel piles ( i.e., 161 dB RMS per Navy, 2015) has been used for the removal of approximately 36 16-in steel pipe piles and 20 fender piles (14- or 16-in steel pipe piles). | ||||
| 2 ?Values in parentheses indicate the calculated proxy source value minus 5 dB of assumed attenuation from the unconfined bubble curtain. | ||||
For this project, two hammers, including any combination of vibratory and impact hammers, may operate simultaneously. As noted earlier, the estimated ensonified area reflects the worst-case scenario (both hammers installing 30-in steel pipe piles) for the project. However, the most likely scenario is the removal of a 16-in timber pile at the same time as installing a 30-in steel pipe pile. The calculated proxy source levels for the different potential concurrent pile driving scenarios are shown in table 5.
Two Impact Hammers
For simultaneous impact driving of two 30-in steel pipe piles (the most conservative scenario), the number of strikes per pile was doubled to estimate total sound exposure during simultaneous installation. While the likelihood of impact pile driving strikes completely overlapping in time is rare due to the intermittent nature and short duration of strikes, NMFS conservatively estimates that up to 20 percent of strikes may overlap completely in time. Therefore, to calculate Level B isopleths for simultaneous impact pile driving, dB addition (if the difference between the two sound source levels is between 0 and 1 dB, 3 dB are added to the higher sound source level) was used to calculate the combined sound source level of 188 dB RMS that was used in this analysis.
One Impact Hammer, One Vibratory Hammer
To calculate Level B isopleths for one impact and one vibratory hammer operating simultaneously, sources were treated as though they were non-overlapping and the isopleth associated with the individual source which results in the largest Level B harassment isopleth was conservatively used for both sources to account for periods of overlapping activities.
Two Vibratory Hammers
To calculate Level B isopleths for two simultaneous vibratory hammers, the NMFS acoustic threshold calculator was used with modified inputs to account for accumulation, weighting, and source overlap in space and time. Using the rules of dB addition if the difference between the two sound source levels is between 0 and 1 dB, 3 dB are added to the higher sound source level), the combined sound source level for the simultaneous vibratory installation of two 30-in steel piles is 166 dB RMS.
The ensonified area associated with Level A harassment is more technically challenging to predict due to the need to account for a duration component. Therefore, NMFS developed an optional User Spreadsheet tool to accompany the Technical Guidance that can be used to relatively simply predict an isopleth distance for use in conjunction with marine mammal density or occurrence to help predict potential takes. We note that because of some of the assumptions included in the methods underlying this optional tool, we anticipate that the resulting isopleth estimates are typically going to be overestimates of some degree, which may result in an overestimate of potential take by Level A harassment. However, this optional tool offers the best way to estimate isopleth distances when more sophisticated modeling methods are not available or practical. For stationary sources, like pile driving, the optional User Spreadsheet tool predicts the distance at which, if a marine mammal remained at that distance for the duration of the activity, it would be expected to incur PTS. Inputs used in the optional User Spreadsheet tool, and the resulting estimated isopleths, are reported in table 6, below.
To calculate Level A isopleths for two impact hammers operating simultaneously, the NMFS User Spreadsheet calculator was used with modified inputs to account for the total estimated number of strikes for all piles. For simultaneous impact driving of two 30-in steel pipe piles (the most conservative scenario), the number of strikes per pile was doubled to estimate total sound exposure during simultaneous installation, and the number of piles per day was reduced to one. The source level for two simultaneous impact hammers was not adjusted because for identical sources the accumulation of energy depends only on the total number of strikes, whether or not they overlap fully in time. Therefore, the source level used for two simultaneous impact hammers was 172 dB single-strike sound exposure level (SEL ss ).
To calculate Level A isopleths of one impact hammer and one vibratory hammer operating simultaneously, sources were treated as though they were non-overlapping and the isopleth associated with the individual source which resulted in the largest Level A isopleth was conservatively used for both sources to account for periods of overlapping activities.
[top] To calculate Level A isopleths of two vibratory hammers operating simultaneously, the NMFS acoustic threshold calculator was used with modified inputs to account for accumulation, weighting, and source overlap in space and time. Using the rules of dB addition (NMFS, 2024; if the difference between the two sound source levels is between 0 and 1 dB, 3 dB are added to the higher sound source
| Scenario | Pile type and proxy | Calculated proxy sound source level |
|---|---|---|
| Two impact hammers | Impact install of 30-in steel pipe pile (172 dB SEL, 185 dB RMS) AND impact install of 30-in steel pipe pile (172 dB SEL, 185 dB RMS) | 172 dB SEL for Level A. 188 dB RMS for Level B |
| One impact hammer, one vibratory hammer | Impact install of 30-in steel pipe pile (172 dB SEL, 185 dB RMS) AND vibratory install of 30-in steel pipe pile (163 dB RMS) | 172 dB SEL for Level A. 163 dB RMS for Level B |
| Two vibratory hammers | Vibratory install of 30-in steel pipe pile (163 dB RMS) AND vibratory install of 30-in steel pipe pile (163 dB RMS) | 166 dB RMS. |
| Pile size and type | Spreadsheet tab used | Weighting factor adjustment (kHz) | Number of piles per day | Duration to drive a single pile (min) | Number of strikes per pile |
|---|---|---|---|---|---|
| Vibratory pile driving and removal | |||||
| 16-in timber pile | A.1. Vibratory pile driving | 2.5 | 8 | 60 | NA |
| 12-in steel pipe | A.1. Vibratory pile driving | 2.5 | 8 | 60 | NA |
| 12-in steel H-pile | A.1. Vibratory pile driving | 2.5 | 8 | 60 | NA |
| 16-in steel pipe | A.1 Vibratory pile driving | 2.5 | 8 | 60 | NA |
| 24-in temporary steel pipe | A.1 Vibratory pile driving | 2.5 | 8 | 60 | NA |
| 30-in steel pipe | A.1. Vibratory pile driving | 2.5 | 8 | 60 | NA |
| Impact pile driving | |||||
| 30-in steel pipe | E.1. Impact pile driving | 2 | 8 | NA | 1000 |
| Concurrent pile driving ? 1 | |||||
| Impact install of 30-in steel pipe pile AND impact install of 30-in steel pipe pile | E.1. Impact pile driving | 2 | 1 | NA | 8000 |
| Impact install of 30-in steel pipe pile AND vibratory install of 30-in steel pipe pile | E.1. Impact pile driving | 2 | 1 | NA | 8000 |
| Vibratory install of 30-in steel pipe pile AND vibratory install of 30-in steel pipe pile | A.1. Vibratory pile driving | 2.5 | 1 | 480 | NA |
| 1 ?Number of strikes is no longer per pile, it is the total number of strikes per day. The number of piles per day has been reduced to one. | |||||
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| Pile size and type | Level A harassment zone (m/km 2 ) | Phocid | Otariid | Level B harassment zone (m/km 2 ) |
|---|---|---|---|---|
| Vibratory pile driving and removal | ||||
| 16-in timber pile | 20/0.000693 | 2/0.000012 | 6,310/8.25 | |
| 12-in steel pipe | 11/0.000226 | 1/0.000003 | 3,415/5.14 | |
| 12-in steel H-pile | 5/0.000055 | 1/0.000003 | 1,585/2.46 | |
| 16-in steel pipe | 17/0.000509 | 2/0.000012 | 5,412/7.47 | |
| 24-in temporary steel pipe | ||||
| 30-in steel pipe | 23/0.000906 | 2/0.000012 | 7,356 a ? b /8.96 | |
| Impact pile driving | ||||
| 30-in steel pipe | 395/0.25181 | 29/0.001393 | 464/0.35 | |
| Concurrent pile driving | ||||
| Impact install of 30-in steel pipe pile AND impact install of 30-in steel pipe pile | 395/0.25181 | 29/0.001393 | 736/0.89 | |
| Impact install of 30-in steel pipe pile AND vibratory install of 30-in steel pipe pile | 7,356 a ? b /8.96 | |||
| Vibratory install of 30-in steel pipe pile AND vibratory install of 30-in steel pipe pile | 36/2,153 | 3/0.000023 | 11,660? b /10.52 | |
| a ?The Level B harassment thresholds for the vibratory installation of a single 30-in steel pile are equivalent to the potential simultaneous installation of up to two 30-inch steel piles using one impact hammer and one vibratory hammer operating concurrently. As noted previously, Levels A and B harassment thresholds for simultaneous pile driving were analyzed based on interim guidance provided by NMFS (2024). | ||||
| b ?The Level B harassment thresholds reported above were calculated using the practical spreading loss model, although the extent of actual sound propagation will be limited to the areas identified in figure 6-3 of Weyerhaeuser's application due to the shape and configuration of the Columbia River in the vicinity. | ||||
Marine Mammal Occurrence and Take Estimation
In this section, we provide information about the occurrence of marine mammals that will inform the take calculations, and describe how the information provided is synthesized to produce a quantitative estimate of the take that is reasonably likely to occur and authorized. Daily occurrence data cones from USACE compiled weekly monitoring reports collected at the Bonneville Dam (river mile (RM) 146) from 2020 through 2021 (van der Leeuw and Tidwell, 2022). As pinnipeds would need to swim past the proposed project site to reach the dam, the number of animals observed at Bonneville Dam may be slightly lower than what would be observed at the project site. The take calculations for this project are:
Incidental take estimate = (number of days during work window × estimated number of animals per day) + (number of days outside work window × estimated number of animals per day).
California Sea Lion
The numbers of California sea lions observed at Bonneville Dam have been in decline in recent years and ranged from 149 in 2016 to a total of 24 in 2021 (van der Leeuw and Tidwell, 2022). During the spring period from January 1 to May 6, 2020, daily counts averaged 0.9 animals ± 3.3 standard deviation, with a high of seven individuals (Tidwell et al., 2020). During spring 2021, California sea lions were present from late March through late May, but in relatively low numbers, with most days having five or fewer present (van der Leeuw and Tidwell, 2022). It is difficult to estimate the number of California sea lions that could potentially occur in the Level B harassment zone during the fall in-water work window from these data, because the numbers at Bonneville Dam reflect a strong seasonal presence in spring. A conservative estimate of three California sea lions per day during the in-water work window and five California sea lions per day outside the in-water work window was used. Therefore, using the equation given above, the estimated number of takes by Level B harassment for California sea lions would be 510.
The largest Level A harassment zone for California sea lions extends 29 m from the sound source (table 7) during impact pile driving. All construction work would be shut down prior to a California sea lion entering the Level A harassment zone specific to the in-water activity underway at the time. In consideration of the small Level A harassment isopleth and proposed shutdown requirements, no take by Level A harassment is anticipated or authorized for California sea lions.
Steller Sea Lion
Steller sea lions have been observed in varying numbers at Bonneville Dam throughout much of the year, with a peak in April and May (Tidwell et al., 2020; van der Leeuw and Tidwell, 2022). Reports from a 2-year period observed daily counts of 12 to 20 Steller sea lions during the fall survey period (Tidwell et al., 2020, Tidwell and van der Leeuw, 2021), and up to 27 Steller sea lions per day in the spring (van der Leeuw and Tidwell, 2022). A conservative estimate of 20 Steller sea lions per day during the in-water work window and 27 Steller sea lions per day outside the in-water work window was used. Therefore, using the equation given above, the estimated number of takes by Level B harassment for Steller sea lions would be 3,210.
The largest Level A harassment zone for Steller sea lions extends 29 m from the sound source (table 7) during impact pile driving. All construction work would be shut down prior to a Steller sea lion entering the Level A harassment zone specific to the in-water activity underway at the time. In consideration of the small Level A harassment isopleth and proposed shutdown requirements, no take by Level A harassment is anticipated or authorized for Steller sea lions.
Harbor Seal
Harbor seals are rarely observed at Bonneville Dam, but have been recorded in low numbers over the past 10 years. A recent IHA issued for the Port of Kalama Manufacturing and Marine Export Facility (85 FR 76527), which is located near the proposed project site, used a conservative estimate based on anecdotal information of harbor seals residing near the mouths of the Cowlitz and Kalama Rivers and estimated that there could be up to 10 present on any given day of pile driving (NMFS, 2017; 81 FR 15064, March 21, 2016). Therefore, using the equation given above, the calculated estimate of take by Level B harassment for harbor seals would be 1,500.
[top] The largest Level A harassment zone for harbor seals extends 395 m from the sound source (table 7) during impact pile driving. The Port of Kalama project estimated that one harbor seal per day could be present in the Level A harassment zone for each day of impact pile driving. Given that the largest Level A isopleth extends approximately half the width of the river (810 m), the calculated estimated take by Level A harassment for harbor seals would be 58 (1 seal on 48.5% of the 120 impact pile driving days).
| Common name | Stock | Stock abundance | Level A harassment | Level B harassment | Total authorized take | Authorized take as a percentage of stock |
|---|---|---|---|---|---|---|
| California sea lion | U.S. Stock | 257,606 | 0 | 510 | 510 | 0.2 |
| Steller sea lion | Eastern DPS | 36,308 | 0 | 3,210 | 3,210 | 8.8 |
| Harbor seal | OR/WA coastal stock | 24,732 | 58 | 1,500 | 1,558 | 6.3 |
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 the activity, and other means of effecting the least practicable 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 (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 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 ensure the least practicable adverse impact on species or stocks and their habitat, as well as subsistence uses where applicable, NMFS considers 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, and impact on operations.
The mitigation measures described in the following paragraphs will apply to the Weyerhaeuser in-water construction activities.
Shutdown and Monitoring Zones
Weyerhaeuser must establish shutdown zones and Level B harassment monitoring zones for all pile driving activities. The purpose of a shutdown zone is generally to define an area within which shutdown of the activity would occur upon sighting of a marine animal (or in anticipation of an animal entering the defined area). Shutdown zones are based on the largest Level A harassment zone for each pile size/type and driving method, and behavioral monitoring zones are meant to encompass Level B harassment zones for each pile size/type and driving method, as shown in table 9. A minimum shutdown zone of 10?m will be required for all in-water construction activities to avoid physical interaction with marine mammals. Shutdown zones for each activity type are shown in table 9.
Prior to pile driving, Protected Species Observers (PSOs) will survey the shutdown zones and surrounding areas for at least 30 minutes before pile driving activities start. If marine mammals are found within the shutdown zone, pile driving will be delayed until the animal has moved out of the shutdown zone, either verified by an observer or by waiting until 15 minutes has elapsed without a sighting. If a marine mammal approaches or enters the shutdown zone during pile driving, the activity will be halted. Pile driving may resume after the animal has moved out of and is moving away from the shutdown zone or after at least 15 minutes has passed since the last observation of the animal.
All marine mammals will be monitored in the Level B harassment to the extent of visibility for the on-duty PSOs. If a marine mammal for which take is authorized enters the Level B harassment zone, in-water activities will continue and PSOs will document the animal's presence within the estimated harassment zone.
If a species for which authorization has not been granted, or for which the authorized takes are met, is observed approaching or within the Level B harassment zone, pile driving activities will be shut down immediately. Activities will not resume until the animal has been confirmed to have left the area or 15 minutes has elapsed with no sighting of the animal.
| Method | Pile size and type | Minimum shutdown zone (m) | Phocid | Otariid | Harassment monitoring zone (m) |
|---|---|---|---|---|---|
| Vibratory | 16-in timber pile removal | 20 | 10 | 6,310 | |
| 12-in steel pipe pile removal | 15 | 10 | 3,415 | ||
| 12-in steel H-pile removal | 10 | 10 | 1,585 | ||
| 16-in steel pipe removal | 20 | 10 | 5,412 | ||
| 24-in steel pipe pile (temporary) installation and removal | 20 | 10 | 5,412 | ||
| 30-in steel pipe pile installation | 25 | 10 | 7,356 | ||
| Impact | 30-in steel pipe pile installation | 200 | 30 | 464 | |
| Concurrent pile driving | Two impact hammers | 200 | 30 | 736 | |
| One impact hammer and one vibratory hammer | 200 | 30 | 7,356 | ||
| Two vibratory hammers | 40 | 10 | 11,660 |
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PSOs
The placement of PSOs during all pile driving and removal activities (described in detail in the Monitoring and Reporting section) will ensure that the ensonified area of the Columbia River is visible during pile installation.
Pre- and Post-Activity Monitoring
Monitoring must take place from 30 minutes prior to initiation of pile driving activities ( i.e., pre-clearance monitoring) through 30 minutes post-completion of pile driving. Prior to the start of daily in-water construction activity, or whenever a break in pile driving 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 considered cleared when a marine mammal has not been observed within the zone for a 30-minute period. If a marine mammal is observed within the shutdown zones, pile driving activity will be delayed or halted. If work ceases for more than 30 minutes, the pre-activity monitoring of the shutdown zones will commence. A determination that the shutdown zone is clear must be made during a period of good visibility ( i.e., the entire shutdown zone and surrounding waters must be visible to the naked eye).
Bubble Curtain
A bubble curtain must be employed during all impact pile driving activities to interrupt the acoustic pressure and reduce impact on marine mammals. The bubble curtain must distribute air bubbles around 100 percent of the piling circumference for the full depth of the water column. The lowest bubble ring must be in contact with the mudline for the full circumference of the ring. The weights attached to the bottom ring must ensure 100 percent substrate contact. No parts of the ring or other objects may prevent full substrate contact. Air flow to the bubblers must be balanced around the circumference of the pile. If simultaneous use of two impact hammers occurs, both piles must be mitigated with bubble curtains as described above.
Soft Start
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 impact hammer operating at full capacity. For impact driving, an initial set of three strikes will be made by the hammer at reduced energy, followed by a 30-second waiting period, then two subsequent three-strike sets before initiating continuous driving. Soft start will 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.
Based on our evaluation of the applicant's proposed measures, NMFS has determined that the proposed mitigation measures provide the means of 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.
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 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:
• 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 activity; 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); and,
• Mitigation and monitoring effectiveness.
Visual Monitoring
Marine mammal monitoring must be conducted in accordance with section 5 of the IHA. Marine mammal monitoring during pile driving and removal must be conducted by NMFS-approved PSOs in a manner consistent with the following:
• PSOs must be independent of the activity contractor (for example, 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 construction activity pursuant to a NMFS-issued incidental take authorization;
• Other PSOs may substitute education (degree in biological science or related field) or training for experience; and,
• Weyerhaeuser must submit PSO Curriculum Vitae for approval by NMFS prior to the onset of pile driving.
PSOs must have the following additional qualifications:
• 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, times, and reason for implementation of mitigation (or why mitigation was not implemented when required); and marine mammal behavior; and,
[top] • 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. Weyerhaeuser will employ up to four PSOs. PSO locations will provide an unobstructed view of all water within the shutdown zone(s), and as much of the Level A harassment and Level B harassment zones as possible. PSOs will be stationed along the shore of the Columbia River.
Weyerhaeuser will ensure that construction supervisors and crews, the monitoring team, and relevant Weyerhaeuser staff are trained prior to the start of activities subject to the proposed IHA, so that responsibilities, communication procedures, monitoring protocols, and operational procedures are clearly understood. New personnel joining during the project will be trained prior to commencing work. Monitoring will occur for all pile driving activities during the pile installation work window (September 1, 2025 through January 31, 2026). For pile removal activities outside the work window, one PSO will be on site to monitor the ensonified area once every 7 calendar days, whether or not vibratory pile extraction occurs on that day. Monitoring will be conducted 30 minutes before, during, and 30 minutes after pile driving/removal 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 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.
Data Collection
PSOs will use approved data forms to record the following information:
• Dates and times (beginning and end) of all marine mammal monitoring.
• PSO locations during marine mammal monitoring.
• Construction activities occurring during each daily observation period, including how many and what type of piles were driven or removed and by what method ( i.e., vibratory or impact).
• Weather parameters and water conditions.
• The number of marine mammals observed, by species, relative to the pile location and if pile driving or removal was occurring at time of sighting.
• Distance and bearings of each marine mammal observed to the pile being driven or removed.
• Description of marine mammal behavior patterns, including direction of travel.
• Age and sex class, if possible, of all marine mammals observed.
• Detailed information about implementation of any mitigation triggered (such as shutdowns and delays), a description of specific actions that ensued, and resulting behavior of the animal if any.
Reporting
A draft marine mammal monitoring report will be submitted to NMFS within 90 days after the completion of pile driving and removal activities. It would include an overall description of work completed, a narrative regarding marine mammal sightings, and associated PSO data sheets. Specifically, the report must include:
• Dates and times (begin and end) of all marine mammal monitoring.
• Construction activities occurring during each daily observation period, including the number and type of piles driven or removed and by what method ( i.e., vibratory driving) and the total equipment duration for cutting for each pile.
• PSO locations during marine mammal monitoring.
• Environmental conditions during monitoring periods (at beginning and end of PSO shift and whenever conditions change significantly), including 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.
• Upon observation of a marine mammal, the following information: (1) name of PSO who sighted the animal(s) and PSO location and activity at time of sighting; (2) time of sighting; (3) identification of the animal(s) ( 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; (4) distance and bearing of each marine mammal observed relative to the pile being driven for each sighting (if pile driving was occurring at time of sighting); (5) estimated number of animals (min/max/best estimate); (6) estimated number of animals by cohort (adults, juveniles, neonates, group composition, etc. ); (7) animal's closest point of approach and estimated time spent within the harassment zone; and (8) description of any marine mammal behavioral observations ( e.g., observed behaviors such as feeding or traveling), including an assessment of behavioral responses thought to have resulted from the activity ( e.g., no response or changes in behavioral state such as ceasing feeding, changing direction, flushing, or breaching).
• Number of marine mammals detected within the harassment zones, by species.
• Detailed information about any implementation of any mitigation triggered ( e.g., shutdowns and delays), a description of specific actions that ensued, and resulting changes in behavior of the animal(s), if any.
If no comments are received from NMFS within 30 days, the draft final report would constitute the final report. If comments are received, a final report addressing NMFS comments must be submitted within 30 days after receipt of comments.
Reporting Injured or Dead Marine Mammals
In the event that personnel involved in the construction activities discover an injured or dead marine mammal, Weyerhaeuser shall report the incident to the OPR, NMFS and to the west coast regional stranding network as soon as feasible. If the death or injury was clearly caused by the specified activity, Weyerhaeuser must 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 the terms of the IHA. The IHA-holder must not resume their activities until notified by NMFS. The report must include the following information:
• Time, date, and location (latitude/longitude) of the first discovery (and updated location information if known and applicable);
• Species identification (if known) or description of the animal(s) involved;
• Condition of the animal(s) (including carcass condition if the animal is dead);
• Observed behaviors of the animal(s), if alive;
• If available, photographs or video footage of the animal(s); and,
• General circumstances under which the animal was discovered.
Negligible Impact Analysis and Determination
[top] 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
To avoid repetition, the discussion of our analysis applies to California sea lions, Steller sea lions, and harbor seals, given that the anticipated effects of this activity on these different marine mammal stocks are expected to be similar. There is little information about the nature or severity of the impacts, or the size, status, or structure of any of these species or stocks that would lead to a different analysis for this activity.
Pile driving activities have the potential to disturb or displace marine mammals. Specifically, the project 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 are present in the ensonified zone when these activities are underway.
The takes from Level B harassment would be due to potential behavioral disturbance, and TTS. Level A harassment takes would be due to PTS. No mortality or serious injury is anticipated given the nature of the activity, even in the absence of the required mitigation. The potential for harassment is minimized through the construction method and the implementation of the mitigation measures (see Mitigation section).
Take would occur within a limited, confined area (the Columbia River) of the stocks' ranges. Level A harassment and Level B harassment would be reduced to the level of least practicable adverse impact through use of mitigation measures described herein. Further, the amount of take authorized is extremely small when compared to stock abundance, and the project is not anticipated to impact any known important habitat areas for any marine mammal species.
Take by Level A harassment is authorized to account for the potential that an animal could enter and remain within the area between a Level A harassment zone and the shutdown zone for a duration long enough to be taken by Level A harassment. Any take by Level A harassment is expected to arise from, at most, a small degree of PTS 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 PTS. Additionally, and as noted previously, some subset of the individuals that are behaviorally harassed could also simultaneously incur some small degree of TTS for a short duration of time. Because of the small degree anticipated, though, any PTS or TTS potentially incurred here would not be expected to adversely impact individual fitness, let alone annual rates of recruitment or survival.
Behavioral responses of marine mammals to pile driving at the project site, if any, are expected to be mild and temporary. Marine mammals within the Level B harassment zone may not show any visual cues they are disturbed by activities or could become alert, avoid the area, leave the area, or display other mild responses that are not observable such as changes in vocalization patterns. Given the limited number of piles to be installed or extracted per day and that pile driving and removal would occur across a maximum of 150 days within the 12-month authorization period, any harassment would be temporary.
Any impacts on marine mammal prey that would occur during Weyerhaeuser's activity would have, at most, short-term effects on foraging of individual marine mammals, and likely no effect on the populations of marine mammals as a whole. Indirect effects on marine mammal prey during the construction are expected to be minor, and these effects are unlikely to cause substantial effects on marine mammals at the individual level, with no expected effect on annual rates of recruitment or survival.
In addition, it is unlikely that minor noise effects in a small, localized area of habitat would have any effect on the stocks' annual rates of recruitment or survival. In combination, we believe that these factors, as well as the available body of evidence from other similar activities, demonstrate that the potential effects of the specified activities will have only minor, short-term effects on individuals. The specified activities are not expected to impact rates of recruitment or survival and will therefore not result in population-level impacts.
In summary and as described above, the following factors primarily support our determination that the impacts resulting from this activity are not expected to adversely affect any of the species or stocks through effects on annual rates of recruitment or survival:
• No serious injury or mortality is anticipated or authorized;
• The intensity of anticipated takes by Level B harassment is relatively low for all stocks and would not be of a duration or intensity expected to result in impacts on reproduction or survival;
• No important habitat areas have been identified within the project area;
• For all species, the Columbia River is a very small and peripheral part of their range and anticipated habitat impacts are minor; and,
• Weyerhaeuser will implement mitigation measures, such as soft-starts for impact pile driving and shut downs to minimize the numbers of marine mammals exposed to injurious levels of sound, and to ensure that take by Level A harassment, is at most, a small degree of PTS.
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 monitoring and mitigation measures, NMFS 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 previously, only take of small numbers of marine mammals 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. When the predicted 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. Additionally, other qualitative factors may be considered in the analysis, such as the temporal or spatial scale of the activities.
[top] Table 8 demonstrates the number of animals that could be exposed to received noise levels that could cause Level B harassment for the work. Our analysis shows that less than 10 percent of each affected stock could be taken by harassment. The numbers of animals authorized to be taken for these stocks
Based on the analysis contained herein of the activity (including the mitigation and monitoring measures) and the authorized 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.
Endangered Species Act
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 whenever we propose to authorize take for endangered or threatened species.
No incidental take of ESA-listed species is authorized 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 action ( i.e., the issuance of an IHA) with respect to potential impacts on the human environment.
This action is consistent with categories of activities identified in Categorical Exclusion B4 (IHAs 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 circumstances that would preclude this categorical exclusion. Accordingly, NMFS has determined that the issuance of this IHA qualifies to be categorically excluded from further NEPA review.
Authorization
NMFS has issued an IHA to Weyerhaeuser for the potential harassment of small numbers of three marine mammal species incidental to the Log Export Dock Project on the Columbia River near Longview, Washington that includes the previously explained mitigation, monitoring and reporting requirements.
Dated: August 2, 2024.
Kimberly Damon-Randall,
Director, Office of Protected Resources, National Marine Fisheries Service.
[FR Doc. 2024-17470 Filed 8-6-24; 8:45 am]
BILLING CODE 3510-22-P