90 FR 48 pgs. 11952-11962 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Eareckson Air Station Fuel Pier Repair in Alcan Harbor on Shemya Island, Alaska
Type: NOTICEVolume: 90Number: 48Pages: 11952 - 11962
Pages: 11952, 11953, 11954, 11955, 11956, 11957, 11958, 11959, 11960, 11961, 11962Docket number: [RTID 0648-XE472]
FR document: [FR Doc. 2025-03953 Filed 3-12-25; 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-XE472]
Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Eareckson Air Station Fuel Pier Repair in Alcan Harbor on Shemya Island, Alaska
AGENCY:
National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce.
ACTION:
Notice; proposed issuance of an incidental harassment authorization; request for comments.
SUMMARY:
NMFS has received a request from the U.S. Army Corps of Engineers (USACE) on behalf of the United States Air Force Pacific Air Forces Regional Support Center (USAF) for an incidental harassment authorization (IHA) that is nearly identical to an IHA previously issued to USAF authorizing the take of marine mammals, by Level A and Level B harassment, incidental to the Eareckson Air Station (EAS) Fuel Pier Repair project in Alcan Harbor on Shemya Island, Alaska. Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting comments on its proposal to issue an IHA to incidentally take marine mammals during the Eareckson Fuel Pier Repair project. NMFS is also requesting comments on a possible 1-year renewal IHA that could be issued under certain circumstances and if all requirements are met, as described in Request for Public Comments at the end of this notice. NMFS will consider public comments prior to making any final decision on the issuance of the requested MMPA authorizations and agency responses will be summarized in the final notice of our decision. The IHA would be valid for one year from the effective date.
DATES:
Comments and information must be received no later than April 14, 2025.
ADDRESSES:
Comments should be addressed to Jolie Harrison, Chief, Permits and Conservation Division, Office of Protected Resources, National Marine Fisheries Service. Written comments should be submitted via email to ITP.Fleming@noaa.gov. Electronic copies of the original application and supporting documents (including NMFS Federal Register notices of the original proposed and final authorizations, and the previous IHA), as well as a list of the references cited in this document, may be obtained online at: https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act. In case of problems accessing these documents, please call the contact listed below.
Instructions: NMFS is not responsible for comments sent by any other method, to any other address or individual, or received after the end of the comment period. Comments, including all attachments, must not exceed a 25-megabyte file size. All comments received are a part of the public record and will generally be posted online at https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act without change. All personal identifying information ( e.g., name, address) voluntarily submitted by the commenter may be publicly accessible. Do not submit confidential business information or otherwise sensitive or protected information.
FOR FURTHER INFORMATION CONTACT:
Kate Fleming, 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 (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 used above are included in the relevant sections below and can be found in section 3 of the MMPA (16 U.S.C. 1362) and NMFS regulations at 50 CFR 216.103.
National Environmental Policy Act
[top] To comply with the National Environmental Policy Act of 1969 (NEPA; 42 U.S.C. 4321 et seq. ) and NOAA Administrative Order (NAO) 216-6A, NMFS must review our proposed action ( i.e., the issuance of an
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 preliminarily determined that the issuance of the proposed IHA qualifies to be categorically excluded from further NEPA review.
We will review all comments submitted in response to this notice prior to concluding our NEPA process or making a final decision on the IHA request.
History of Request
On May 15, 2023, NMFS received an application from USACE on behalf of USAF for an IHA to take marine mammals incidental to construction associated with the EAS Fuel Pier repair in Alcan Harbor on Shemya Island, Alaska. NMFS published a notice of a proposed IHA and request for comments in the Federal Register on October 10, 2023 (88 FR 74451). On March 5, 2024, NMFS issued an IHA that was effective from April 1, 2024 through March 31, 2025 (89 FR 17423, March 11, 2024). In-water work associated with the project was expected to be completed between April and October 2024.
On September 23, 2024, USAF informed NMFS that work on the project had experienced significant delays due to piling production delays and weather and would not be completed during the 2024 IHA time period USAF completed a portion of the construction work that was covered by the 2024 IHA and submitted a monitoring report demonstrating that the required mitigation and monitoring requirements were satisfied, no impacts of a scale or nature not previously analyzed or authorized occurred as a result of the activities conducted, and the IHA holder did not exceed the authorized levels of take under that IHA.
On September 23, 2024, NMFS received a letter from USAF requesting renewal of the 2024 IHA (2024 request) to conduct nearly identical construction activities that were previously analyzed under the 2024 IHA. On May 3, 2024, NMFS published (89 FR 36762) and solicited public comment on its draft updated Technical Guidance for Assessing the Effects of Anthropogenic Sound on Marine Mammal Hearing Underwater and In-Air Criteria for Onset of Auditory Injury and Temporary Threshold Shifts (Version 3.0) (2024 Technical Guidance), which includes updated thresholds and weighting functions to inform auditory injury (AUD INJ) estimates. The public comment period ended on June 17th, 2024, and the 2024 Technical Guidance was finalized on October 24, 2024. While USAF's planned activity would ordinarily qualify for a renewal of the IHA, NMFS determined that a renewal of the 2024 IHA is not appropriate in this case because application of the updated Guidance indicates that substantial modification of the prescribed shutdown zones and updates to authorized take numbers for certain species is appropriate.
On December 16, 2024, USAF revised their request to indicate that all work completed during the 2024 season would need to be redone, due to shifting sediments and improperly functioning piles. As such, the same work analyzed under the 2024 IHA is planned for the current IHA, across the same number of construction days. This includes the (1) installation of 208 42-inch round steel interlocking pipe piles (2) the installation of 60 30-inch steel template piles and, (3) the removal of 64 30-inch steel template piles, which includes the removal of 4 additional piles that were installed under the 2024 IHA.
Additionally, USAF also requested to reduce the size of the shutdown zones established for low-frequency cetaceans due to practicability concerns associated with excessive fog. Under this proposed IHA, USAF would conduct pile driving activities between the in water work window dates of April 2025 through October 2025. The proposed activities are nearly identical to those analyzed under the 2024 IHA, but the mitigation zones and number of authorized takes have been adjusted to account for the isopleths calculated using the 2024 Technical Guidance and the request to adjust the shutdown zone for low frequency cetaceans. The USAF request was deemed adequate and complete on January 23, 2024. In evaluating the request, and where applicable, NMFS relies on the information previously presented in notices associated with issuance of the 2024 IHA (88 FR 74451, October 31, 2023; 89 FR 17423, March 11, 2024).
Description of the Proposed Activity and Anticipated Impacts
USAF is conducting long-term repairs on the only existing fuel pier at EAS on Shemya Island, Alaska. The 2024 IHA was based on the installation and removal of sixty 30-inch piles and the installation of 208 42-inch round steel interlocking pipe piles over an estimated 160 days of pile driving and removal (table 1), between April and October, 2024. USAF did not complete most of the work in 2024, and work that was attempted will need to be redone. Between August 23, 2024 and September 19, 2024: (1) six out of sixty 30-inch temporary steel pipe piles were installed, (2) two out of sixty 30-inch temporary steel piles were removed, (3) five out of 208 42-inch round steel interlocking pipe piles were installed, and (4) unplanned, all five 42-inch round steel interlocking pipe piles were removed because they were interlocking improperly. As such, USAF requests that this proposed IHA cover take incidental to the same activity analyzed under the 2024 IHA: (1) installation of 208 42? round steel interlocking pipe piles (2) installation of 60 30-inch steel template pipe piles and (3) removal of 64 30? template pipe piles, which includes the removal of 4 additional piles that were installed under the 2024 IHA, (table 1) across the same number of construction days (n = 160) between April and October 2025.
To support public review and comment on the IHA that NMFS is proposing to issue here, we refer to the documents related to the previously issued IHA and discuss any new or changed information here. These previous documents include the Federal Register notice of the issuance of the 2024 IHA for USAF's Fuel Pier Repair project (89 FR 17423, March 11, 2024), and the Federal Register notice of the proposed IHA (88 FR 74451, October 31, 2023) and all associated references and documents. The descriptions and analyses contained in those documents remain accurate with the exception of the minor modifications described herein. A detailed description of the proposed vibratory removal and vibratory and impact pile driving and down-the-hole (DTH) activities at the fuel pier repair project is found in these documents. We also refer the reader to USAF's previous application and final monitoring report for the 2024 construction activities, which can be found at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities .
Detailed Description of the Action
[top] A detailed description of the proposed construction activities is found in these previous documents. Excepting the piles that have already been driven, the location, timing, and nature of the activities, including the
| Installation or removal | Number of piles planned under 2024 IHA | Number of piles installed or removed under 2024 IHA | Number of piles remaining | Construction days? 3 |
|---|---|---|---|---|
| Installation of 42-inch Interlocking Steel Pipe Piles | 208 | 5 | 208 | 122 |
| Removal of 42-inch Interlocking Steel Pipe Piles | 0 | 1 ?5 | 0 | |
| Installation of 30-inch Steel Pipe Piles-Template | 60 | 6 | 60 | 17 |
| Removal of 30-inch Steel Pipe Piles-Template | 60 | 2 | 2 ?64 | |
| 1 ?42-inch interlocking steel pipe piles were not intended for removal. USAF removed five of these piles to address an issue with their function ( i.e., they were not interlocking properly). | ||||
| 2 ?4 30-inch template piles emplaced in 2024 that have not yet been removed are planned for removal in 2025 due to expected shifting. They were left in place to provide reinforcement to the current degraded/unstable structure. | ||||
| 3 ?USAF estimates 160 construction days in 2025 to account for weather delays and mechanical issues. | ||||
Description of Marine Mammals
A detailed description of the species likely to be affected by USAF's Fuel Pier Repair project, including brief introductions to the species and relevant stocks, available information regarding population trends and threats, and information regarding local occurrence, were provided in the Federal Register notice for the proposed IHA (88 FR 74451, October 21, 2023); 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. NMFS reviewed the most recent SARs (found on NMFS' website at https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments ), up-to-date information on relevant Unusual Mortality Events (UMEs; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-unusual-mortality-events ), and recent scientific literature and determined that the new information does not change our original analysis of impacts under the 2024 IHA. 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.
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| Common name | Scientific name | Stock | ESA/ MMPA status; strategic (Y/N)? 1 | Stock abundance (CV, N min , most recent abundance survey)? 2 | PBR | Annual M/SI? 3 |
|---|---|---|---|---|---|---|
| Order Artiodactyla-Infraorder Cetacea-Mysticeti (baleen whales) | ||||||
| Family Balaenopteridae: | ||||||
| Fin whale | Balaenoptera physalus | Northeast Pacific | E, D, Y | UND (UND, UND, 2013)? 4 | UND | 0.6 |
| Humpback whale | Megaptera novaeangliae | Western North Pacific | E, D, Y | 1,084, (0.088, 1,007, 2006) | 3.4 | 5.82 |
| Mexico-North Pacific | T, D, Y | N/A (N/A, N/A, 2006)? 5 | UND | 0.56 | ||
| Hawai'i | -, -, N | 11,278 (0.56, 7,265, 2020) | 127 | 19.6 | ||
| Minke whale | Balaenoptera acutorostrata | Alaska | -, -, - | N/A (N/A, N/A, N/A)? 6 | UND | 0 |
| Odontoceti (toothed whales, dolphins, and porpoises) | ||||||
| Family Physeteridae: | ||||||
| Sperm whale | Physeter macrocephalus | North Pacific | E, D, Y | UND (UND, UND, 2015)? 7 | UND | 3.5 |
| Family Ziphiidae (beaked whales): | ||||||
| Baird's beaked whale | Berardius bairdii | Alaska | -, -, N | N/A (N/A, N/A, N/A)? 8 | N/A | 0 |
| Stejneger's beaked whale | Mesoplodon stejnegeri | Alaska | -, -, N | N/A (N/A, N/A, N/A)? 8 | N/A | 0 |
| Family Delphinidae: | ||||||
| Killer whale | Orcinus orca | ENP Alaska Resident Stock | -, -, N | 1,920 (N/A, 1,920, 2019) | 19 | 1.3 |
| ENP Gulf of Alaska, Aleutian Islands, and Bering Sea | -, -, N | 587 (N/A, 587, 2012) | 5.9 | 0.8 | ||
| Family Phocoenidae (porpoises): | ||||||
| Dall's porpoise | Phocoenoides dalli | Alaska | -, -, N | UND (UND, UND, 2015)? 9 | UND | 37 |
| Harbor porpoise | Phocoena phocoena | Bering Sea | -, -, Y | UNK (UNK, N/A, 2008)? 10 | UND | 0.4 |
| Order Carnivora-Pinnipedia | ||||||
| Family Otariidae (eared seals and sea lions): | ||||||
| Northern fur seal | Callorhinus ursinus | Eastern Pacific | -, D, Y | 626,618 (0.2, 530,376, 2019) | 11,403 | 373 |
| Steller sea lion? 11 | Eumetopias jubatus | Western, U.S | E, D, Y | 49,837 (N/A, 49,837, 2022) | 299 | 267 |
| Family Phocidae (earless seals): | ||||||
| Harbor seal | Phoca vitulina | Aleutian Islands | -, -, N | 5,588 (N/A, 5,366, 2018) | 97 | 90 |
| 1 ?Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed under the ESA is automatically designated under the MMPA as depleted and as a strategic stock. | ||||||
| 2 ?NMFS marine mammal stock assessment reports online at: https://www.nmfs.noaa.gov/pr/sars. CV is coefficient of variation; N min is the minimum estimate of stock abundance. In some cases, CV is not applicable (explain if this is the case). | ||||||
| 3 ?These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined ( e.g., commercial fisheries, vessel strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV associated with estimated mortality due to commercial fisheries is presented in some cases. | ||||||
| 4 ?The best available abundance estimate for this stock is not considered representative of the entire stock as surveys were limited to a small portion of the stock's range. Based upon this estimate and the N min , the PBR value is likely negatively biased for the entire stock. | ||||||
| 5 ?Abundance estimates are based upon data collected more than 8 years ago and therefore current estimates are considered unknown. | ||||||
| 6 ?Reliable population estimates are not available for this stock. Please see Friday et al. (2013) and Zerbini et al. (2006) for additional information on numbers of minke whales in Alaska. | ||||||
| 7 ?The most recent abundance estimate is likely unreliable as it covered a small area that may not have included females and juveniles, and did not account for animals missed on the trackline. The calculated PBR is not a reliable index for the stock as it is based upon negatively biased minimum abundance estimate. | ||||||
| 8 ?Reliable abundance estimates for this stock are currently unavailable. | ||||||
| 9 ?The best available abundance estimate is likely an underestimate for the entire stock because it is based upon a survey that covered only a small portion of the stock's range. | ||||||
| 10 ?The best available abundance estimate and Nmin are likely an underestimate for the entire stock because it is based upon a survey that covered only a small portion of the stock's range. PBR for this stock is undetermined due to this estimate being older than 8 years. | ||||||
| 11 ?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. The overall N min is 73,211 and overall PBR is 439. | ||||||
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, 2024) 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. Note that since the issuance of the 2024 IHA, NMFS' 2024 Technical Guidance was finalized and has been incorporated into this analysis. The re-named marine mammal hearing groups that have been incorporated into this proposed 2025 IHA are presented in table 3. The references, analysis, and methodology used in the development of the thresholds are described in the 2024 Technical Guidance, which may be accessed at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.
| Hearing group | Generalized hearing range?* |
|---|---|
| Low-frequency (LF) cetaceans (baleen whales) | 7 Hz to 36 kHz. |
| High-frequency (HF) cetaceans (dolphins, toothed whales, beaked whales, bottlenose whales) | 150 Hz to 160 kHz. |
| Very High-frequency (VHF) cetaceans (true porpoises, Kogia, river dolphins, Cephalorhynchid, Lagenorhynchus cruciger & L. australis ) | 200 Hz to 165 kHz. |
| Phocid pinnipeds (PW) (underwater) (true seals) | 40 Hz to 90 kHz. |
| Otariid pinnipeds (OW) (underwater) (sea lions and fur seals) | 60 Hz to 68 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 may not be as broad. Generalized hearing range chosen based on ~65 dB threshold from composite audiogram, previous analysis in NMFS 2018, and/or data from Southall et al. 2007; Southall et al. 2019. Additionally, animals are able to detect very loud sounds above and below that "generalized" hearing range. | |
For more detail concerning these groups and associated frequency ranges, please see NMFS (2024) for a review of available information.
Potential Effects on Marine Mammals and Their Habitat
The effects of underwater noise from USAF's construction activities have the potential to result in the harassment of marine mammals in the vicinity of the project area. The notice of proposed 2024 IHA (88 FR 74451, October 31, 2024) included a discussion of the effects of anthropogenic noise on marine mammals and the potential effects of underwater noise from USAF's construction on marine mammals and their habitat. That information and analysis is not repeated here; please refer to the notice of proposed 2024 IHA (88 FR 74451, October 31, 2024).
Estimated Take
[top] A detailed description of the methods and inputs used to estimate authorized take is found in these previous
Level A Harassment -NMFS' 2024 Technical Guidance (NMFS, 2024) 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). Between the issuance of the 2024 IHA and this proposed 2025 IHA, NMFS' 2024 Technical Guidance was updated and has been incorporated into this analysis. USAF's activity includes the use of impulsive (impact pile driving and DTH) and non-impulsive (continuous pile driving and DTH) sources. The updated thresholds, which identify the Onset of AUD INJ based on the 2024 Technical Guidance, have been incorporated in this proposed IHA are presented in table 4. The references, analysis, and methodology used in the development of the thresholds are described in the 2024 Technical Guidance, which may be accessed at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance. NMFS defines AUD INJ as "damage to the inner ear that can result in destruction of tissue . . . which may or may not result in PTS" (NMFS 2024). NMFS defined PTS as a permanent, irreversible increase in the threshold of audibility at a specified frequency or portion of an individual's hearing range above a previously established reference level (NMFS, 2024).
| Hearing group | AUD INJ onset thresholds?* (received level) | Impulsive | Non-impulsive |
|---|---|---|---|
| Low-Frequency (LF) Cetaceans | Cell 1: L p, 0-pk,flat : 222 dB; L E, p, LF,24h : 183 dB | Cell 2: L E, p, LF,24h : 197 dB. | |
| High-Frequency (HF) Cetaceans | Cell 3: L p, 0-pk,flat : 230 dB; L E, p, LF,24h : 193 dB | Cell 4: L E, p, HF,24h : 201 dB. | |
| Very High-Frequency (VHF) Cetaceans | Cell 5: L p, 0-pk,flat : 202 dB; L E, p, VHF,24h : 159 dB | Cell 6: L E, p, VHF,24h : 181 dB. | |
| Phocid Pinnipeds (PW) (Underwater) | Cell 7: L p, 0-pk.flat : 223 dB; L E, p, PW,24h : 183 dB | Cell 8: L E, p, PW,24h : 195 dB. | |
| Otariid Pinnipeds (OW) (Underwater) | Cell 9: L p, 0-pk,flat : 230 dB; L E, p, OW,24h : 185 dB | Cell 10: L E, p, OW,24h : 199 dB. | |
| *?Dual metric thresholds for impulsive sounds: Use whichever results in the largest isopleth for calculating AUD INJ onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level thresholds associated with impulsive sounds, these thresholds are recommended for consideration. | |||
| Note: Peak sound pressure level ( L p, 0-pk ) has a reference value of 1 micropascal (µPa), and weighted cumulative sound exposure level ( L E, p ) has a reference value of 1µPa 2 s. In this table, thresholds are abbreviated to be more reflective of International Organization for Standardization standards (ISO 2017). The subscript "flat" is being included to indicate peak sound pressure are flat weighted or unweighted within the generalized hearing range of marine mammals [ i.e., 7 Hertz (Hz) to 165 kHz]. The subscript associated with cumulative sound exposure level thresholds indicates the designated marine mammal auditory weighting function (LF, HF, and VHF cetaceans, and PW and OW pinnipeds) and that the recommended accumulation period is 24 hours. The weighted 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 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 planned project. Marine mammals are expected to be affected via sound generated by the primary components of the project ( i.e., pile driving and removal).
The project includes vibratory pile installation and removal, impact pile driving, and DTH. Source levels for these activities are based on reviews of measurements of the same or similar types and dimensions of piles available in the literature. Source levels for each pile size and activity each year are presented in table 5. Source levels for vibratory installation and removal of piles of the same diameter are assumed to be the same.
| Pile driving method | Pile type | Pile size | dB RMS | dB peak | dB SEL | Reference |
|---|---|---|---|---|---|---|
| Vibratory Installation and Removal | Temporary steel pipe pile | 30 | 166 | N/A | N/A | NMFS 2023 Analysis. |
| Round interlocking steel pipe pile | 42 | 168.2 | N/A | N/A | Port of Anchorage Test Pile Program (Table 16 in Austen et al., 2016). | |
| Impact Installation | Temporary steel pipe pile | 30 | 191 | 212 | 171 | Caltrans, 2020. |
| Round interlocking steel pipe pile | 42 | 192 | 213 | 179 | Caltrans, 2020. | |
| Down-the-Hole Installation | Temporary steel pipe pile | 30 | 174 | 164 | 194 | Reyff & Heyvaert 2019, Reyff, 2020, Denes et al., 2019. |
| Round interlocking steel pipe pile | 42 | 174 | 164 | 194 | Reyff & Heyvaert 2019, Reyff, 2020, Denes et al., 2019. | |
| Note: dB peak = peak sound level; rms = root mean square; SEL = sound exposure level. | ||||||
| *?All sound levels are referenced at 10?m. | ||||||
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TL is the decrease in acoustic intensity as an acoustic pressure wave propagates out from a source. TL parameters vary with frequency, temperature, sea conditions, current, source and receiver depth, water depth, water chemistry, and bottom composition and topography. The general formula for underwater TL is:
TL = B × Log10 ( R 1 / R 2 ),
Where:
TL = transmission loss in dB
B = transmission loss coefficient
R 1 = the distance of the modeled SPL from the driven pile, and
R 2 = the distance from the driven pile of the initial measurement
Absent site-specific acoustical monitoring with differing measured TL, a practical spreading value of 15 is used as the TL coefficient in the above formula. Site-specific TL data for Alcan Harbor are not available; therefore, the default coefficient of 15 is used to determine the distances to the Level A harassment and Level B harassment thresholds.
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 2024 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 such as 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 AUD INJ, which includes, but is not limited to, PTS. Inputs used in the optional User Spreadsheet tool are identical to those analyzed under the 2024 IHA. Table 6 provides the calculated Level A harassment isopleths that are based the 2024 Technical Guidance that are incorporated into this analysis compared with the calculated Level A harassment isopleths that were based on the 2018 Technical Guidance and presented in the proposed FRN for the 2024 IHA (88 FR 74451, October 31, 2023)
There were no substantive changes to Level A harassment isopleths for low frequency cetaceans (they increased slightly during vibratory activities and decreased slightly during impact pile driving). However, for high-frequency cetaceans (categorized as mid-frequency cetaceans prior to application of the 2024 Technical Guidance), phocids, and otariids, Level A harassment isopleths increased substantially during all pile driving activities. Additionally, for very high frequency cetaceans (categorized as high frequency cetaceans prior to application of the 2024 Technical Guidance), Level A harassment isopleths decreased slightly during vibratory activities and substantially during impact pile driving.
| Pile size/type | Level A harassment isopleths (m) | LF | HF? 1 | VHF? 2 | PW | OW | Level B harassment isopleth (m) |
|---|---|---|---|---|---|---|---|
| Vibratory | |||||||
| 42-inch Interlocking Steel | 44.2 (32.7) | 17.0 (2.9) | 36.1 (48.4) | 56.9 (19.9) | 19.2 (1.4) | 16,343 | |
| 30-inch Steel Pipe | 19.9 (14.7) | 7.6 (1.3) | 16.2 (21.8) | 25.6 (8.9) | 8.6 (0.6) | 11,659 | |
| DTH | |||||||
| 42-inch Interlocking Steel | 2,540 (2,549.4) | 324.1 (90.7) | 3,930.8 (3,036.7) | 2,256.5 (1,364.3) | 841.1 (99.3) | 39,811 | |
| 30-inch Steel Pipe | 2,249.4 (2,257.6) | 287.0 (80.3) | 3,480.9 (2,689.2) | 1,998.2 (1,208.2) | 744.9 (88) | 39,811 | |
| Impact | |||||||
| 42-inch Interlocking Steel | 2,007.8 (2.015.1) | 256.2 (71.7) | 3,107.0 (2,400.3) | 1,783.6 (1,078.4) | 664.9 (78.5) | 1,359 | |
| 30-inch Steel Pipe | 930.4 (933.8) | 118.7 (33.2) | 1,439.9 (1,112.3) | 826.6 (499.7) | 308.1 (36.4) | 1,166 | |
| 1 ?Species that were considered Mid-Frequency cetaceans under the NMFS 2018 Technical Guidance are now considered High Frequency cetaceans. | |||||||
| 2 ?Species that were considered High-Frequency cetaceans under the NMFS 2018 Technical Guidance are now considered Very High Frequency cetaceans. | |||||||
Except for harbor seal, the same occurrence assumptions that were used to estimate take for the 2024 IHA and described in the associated proposed FRN (88 FR 74451, October 31, 2024) are applied here, as is the same duration information. In cases where site specific marine mammal monitoring data are available, marine mammal occurrence assumptions and pile driving durations are based on hourly estimates. In cases where no marine mammal observations were reported, marine mammal occurrence assumptions and pile driving durations are based on daily estimates.
During monitoring completed in 2024, 29 harbor seal and six Steller sea lion were observed in the project area (at a rate of 0.45 and 0.09 groups of one of each species per hour, respectively). A total of 6 harbor seal and 2 Steller sea lion were reported within the Level B harassment zone while construction activities were underway. This suggests a revision to harbor seal occurrence estimates is appropriate; 0.45 harbor seals per hour were reported during 2024 activities rather than the previously estimated 0.14 harbor seal per hour used in the analysis for the 2024 IHA.
The equation used to estimate take by Level B harassment for all species is:
Exposure Estimate = marine mammal occurrence × duration of pile driving
[top] During all vibratory pile driving activities for all hearing groups, and during all other activities for high frequency cetaceans (categorized as mid-frequency cetaceans in the 2024 IHA and prior to the application of the
To calculate estimated take by Level A harassment in cases where the Level A harassment isopleth is larger than the Level B harassment isopleth, the same equation to estimate take by Level B harassment is applied. Exposure estimates for those activities are attributed to take by Level A harassment.
To calculate estimated take by Level A harassment in cases where the Level A harassment isopleth is larger than the planned shutdown zone, but smaller than the Level B harassment isopleth, we proportionally compared, by hearing group, the portion of the largest Level A harassment area (km 2 ) that exceeds the planned shutdown zone area (km 2 ) to the area (km 2 ) (referred to as the Level A harassment impact area) of the largest Level B harassment isopleth across that pile type (typically from vibratory pile driving). This ratio was then multiplied by the total estimated marine mammal exposures:
Take by Level A harassment = Level A harassment impact area (km 2 )/Level B harassment area (km 2 ) × total marine mammal exposures.
Monitoring data collected during work at the project site indicate that all Steller sea lion were observed within 200 m of the project site, and harbor seal were observed between 50 m and 500 m in 2021 and 85 and 600 m in 2024. As such, for harbor seal and Steller sea lion, NMFS determined that the methods above could underestimate potential take by Level A harassment. NMFS accordingly estimated additional takes by Level A harassment by determining the ratio of each species that were observed beyond the proposed shutdown zone compared to the number of individuals that were observed closer to construction activities during the EAS fuel pier emergency repair completed in 2021 and 2024, and multiplying this ratio by the total exposures.
Note that in the 2024 IHA, an additional approach to estimate take by Level A harassment was employed to account for cases in which a shutdown zone was established at the Level A harassment isopleth, but a portion of the shutdown zone was not expected to be reliably observable. Since the proposed shutdown zones for low frequency cetaceans have been reduced to address practicability concerns, this scenario is no longer applicable and as such, that approach is not summarized here or applied to take estimates for any hearing group.
Fin Whale
One group of eight fin whale is predicted every 2 construction months (60 days). The duration of the construction is 160 days (2.65 is the basic 60 day period that corresponds to 2 construction months). This results in 21 takes by Level B harassment of fin whale (8 fin whale × 2.65 2-month periods).
During DTH activities, the Level A harassment isopleth is larger than the shutdown zone, but smaller than the Level B harassment isopleth. Estimated take by Level A harassment for these activities results in 0.084 based on (5.8 km 2 /1,285.9 km 2 ) × 21 fin whale exposures = 0.084 takes by Level A harassment. During impact pile driving of 42-inch piles, the Level A harassment isopleth is larger than the Level B harassment isopleth. Estimated take by Level A harassment for these activities results in 6.88 based on 8 fin whale × 0.86 months of 42-inch impact pile driving.
Takes by Level B harassment were modified to deduct the proposed amount of take by Level A harassment ( i.e., 21-6.88-0.084 = 14). Therefore, NMFS proposes to authorize 7 takes by Level A harassment and 14 takes by Level B harassment for fin whale, for a total of 21 takes.
Humpback Whale
A total of 0.07 groups of two humpback whale are predicted every construction hour. The duration of the construction hours is 1,101. This results in 154 takes by Level B harassment of humpback whale (0.07 groups × 2 humpback whale × 1,101 hours).
During DTH activities, the Level A harassment isopleth is larger than the shutdown zone, but smaller than the Level B harassment isopleth. Estimated take by Level A harassment for these activities results in 0.616 based on (5.8 km 2 /1,285.9 km 2 ) × 154 exposures = 0.616 takes by Level A harassment. During impact pile driving of 42-inch piles, the Level A harassment isopleth is larger than the Level B harassment isopleth. Estimated take by Level A harassment for these activities results in 21.84 based on 0.07 humpback whales × 2 groups × 156 hours.
Takes by Level B harassment were modified to deduct the proposed amount of take by Level A harassment ( i.e., 154-21.84-0.616 = 131). Therefore, NMFS proposes to authorize 23 takes by Level A harassment for humpback whale and 131 takes by Level B harassment for humpback whale, for a total of 22 takes.
Minke Whale
One group of three minke whale is predicted every 2 construction months (60 days). The duration of the construction is 160 days (2.65 is the basic 60 day period that corresponds to 2 construction months). This results in eight takes by Level B harassment of minke whale (3 minke whale × 2.65 2-month periods).
During DTH activities, the Level A harassment isopleth is larger than the shutdown zone, but smaller than the Level B harassment isopleth. Estimated take by Level A harassment for these activities results in 0.032 based on (5.8 km 2 /1,285.9 km 2 ) × 8 minke whale exposures = 0.032 takes by Level A harassment. During impact pile driving of 42-inch piles, the Level A harassment zone is larger than the Level B harassment zone. Estimated take by Level A harassment for these activities results in 2.58 minke whale based on 3 minke whale × 0.86 months of 42-inch impact pile driving. Takes by Level B harassment were modified to deduct the proposed amount of take by Level A harassment ( i.e., 8-2.58-0.032 = 5). Therefore, NMFS proposes to authorize three takes by Level A harassment and five takes by Level B harassment for minke whale, for a total of eight takes.
Sperm Whale
Two groups of four sperm whale is predicted every 1 construction month. The duration of the construction is 5 months. This results in 40 takes by Level B harassment of sperm whale (2 groups × 4 sperm whale × 5 construction months).
Takes by Level A harassment for sperm whales are not anticipated nor are they proposed for authorization.
Baird's Beaked Whale
[top] One group of 10 Baird's beaked whales is predicted across the project, which is based on this species being shy and preferring deep waters and as such the applicant predicted they would be very rare in the project area. Therefore, NMFS proposes to authorize 10 takes of Baird's beaked whale by Level B harassment.
Takes by Level A harassment for Baird's beaked whale were not anticipated nor are they proposed for authorization.
Stejneger's Beaked Whale
One group of eight Stejneger's beaked whales is predicted across the project, which is based on this species being shy and preferring deep waters and as such the applicant predicted they would be very rare in the project area. Therefore, NMFS proposes to authorize eight takes of Stejneger's beaked whale by Level B harassment.
Takes by Level A harassment for Stejneger's beaked whale were not anticipated nor are they proposed for authorization.
Killer Whale
A total of 0.02 groups of 8 killer whale is predicted every construction hour. The duration of the construction hours is 1,101. This results in 176 takes by Level B harassment of killer whale (0.02 groups × 8 killer whale × 1,101 hours).
Takes by Level A harassment for killer whale were not anticipated nor are they proposed for authorization.
Dall's Porpoise
One group of 15 Dall's porpoise is predicted every 2 construction months (60 days). The duration of the construction is 160 days (2.65 × the basic 60 day period that corresponds to 2 construction months). This results in 15 takes by Level B harassment of Dall's porpoise (15 Dall's porpoise × 2.65 2-month periods = 39 takes by Level B harassment).
During DTH activities, the Level A harassment isopleth is larger than the shutdown zone, but smaller than the Level B harassment isopleth. Estimated take by Level A harassment for these activities results in 0.48 takes based on (15.62 km 2 /1,285.9 km 2 ) × 40 exposures = 0.48. During all impact pile driving, the Level A harassment isopleth is larger than the Level B harassment isopleth. Estimated take by Level A harassment for these activities result in 18.4 based on 1 group × 15 Dall's porpoise × 0.86 months of 42-inch impact pile driving and 1 group × 15 Dall's porpoise × 0.37 months of 30-inch impact pile driving (12.9 + 5.5 = 18.4 takes by Level A harassment).
Takes by Level B harassment were modified to deduct the proposed amount of take by Level A harassment ( i.e., 39-18.4-0.48 = 20). Therefore, NMFS proposes to authorize 19 takes by Level A harassment and 20 takes by Level B harassment for Dall's porpoise, for a total of 39 takes.
Harbor Porpoise
One group of three harbor porpoise is predicted every 1 construction month. The duration of the construction is 5 months. This results in 15 takes by Level B harassment of harbor porpoise (1 group × 3 harbor porpoise × 5 months).
During DTH activities, the Level A harassment isopleth is larger than the shutdown zone, but smaller than the Level B harassment isopleth. Estimated take by level A harassment during these activities results in 0.18 based on (15.6 km 2 /1,285.9 km 2 ) × 15 harbor porpoise exposures. During all impact pile driving activities, the Level A harassment isopleth is larger than the Level B harassment isopleth. This results in 8.8 takes by Level A harassment based on 1 group × 3 harbor porpoise × 0.17 months of 42-inch impact pile driving and 1 group × 3 harbor porpoise × 0.73 months of 30-inch impact pile driving ( i.e., 5.1 + 3.73 = 8.83).
Takes by Level B harassment were modified to deduct the proposed amount of take by Level A harassment ( i.e., 15 - 8.83 - 0.18 = 6). Therefore, NMFS proposes to authorize 6 takes by Level A harassment and 9 takes by Level B harassment for harbor porpoise, for a total of 15 takes.
Northern Fur Seal
To account for the unlikely but small possibility that northern fur seals could occur in the project area NMFS estimates that one group of one northern fur seal could occur in the project area each construction month either in the Level B or Level A harassment isopleth. As such, NMFS proposes to authorize a maximum total of five takes of northern fur seal by either Level B or Level A harassment.
Steller Sea Lion
A total of 0.09 groups of one Steller sea lion is predicted every construction hour. The duration of the construction hours is 1,101. This results in 99 takes by Level B harassment of Steller sea lion (0.09 Steller sea lion × 1 group × 1,101 hours = 99 takes by Level B harassment).
During DTH activities, the Level A harassment isopleth is larger than the shutdown zone, but smaller than the Level B harassment isopleth. Estimated take by Level A harassment for these activities results in 0.0007 based on (0.91 km 2 /1,285.9 km 2 ) × 154 exposures.
Monitoring data collected during work completed at the project site in 2021 and 2024 indicate that Steller sea lion occasionally occur within the project area, within 200 m from shore; on 6 days in 2021, 7 Steller sea lion were observed between 25 m and 175 m from the project site. On 3 days in 2024, 6 Steller sea lion were observed between 100 and 200 m of the project site. Because Steller sea lion typically inhabit areas closer to shore rather than distances represented by the largest level B harassment isopleth (39,811 m), NMFS determined that the method above could underestimate potential take by Level A harassment. NMFS accordingly estimated additional takes by Level A harassment by determining the ratio of Steller sea lion that were observed beyond the proposed shutdown zone isopleth compared to the Steller sea lion that were observed closer to construction activities during the EAS fuel pier emergency repair that was completed in 2021 and EAS fuel pier repair activities completed in 2024. However, all Steller sea lion reported by PSOs during that project were reported within the established shutdown zone (n = 13). To be conservative, NMFS assumes that a small proportion (10 percent) of Steller sea lion predicted to occur within the project area during construction could occur outside of the shutdown zone. As such, NMFS predicts that 10 Steller sea lion (99 total exposures × 0.1 = 9.9 takes by Level A harassment).
Takes by Level B harassment were modified to deduct the proposed amount of take by Level A harassment ( i.e., 99 - 10 = 89 takes by Level B harassment). Therefore, NMFS proposes to authorize 10 takes by Level A harassment and 89 takes by Level B harassment for Steller sea lion, for a total of 154 takes.
Harbor Seal
A total of 0.45 groups of one harbor seal is predicted every construction hour. This is increased from the predicted 0.14 groups of one harbor seal every construction hour used in the 2024 IHA due to application of the most recent monitoring data. The duration of the construction hours is 1,101. This results in 495 takes by Level B harassment of harbor seal based on 0.45 harbor seal × 1 group × 1,101 hours.
During DTH activities, the Level A harassment isopleth is larger than the shutdown zone, but smaller than the Level B harassment isopleth. Estimated take by Level A harassment for these activities results in 2.0 based on (4.8 km 2 /1,285.9 km 2 ) × 495 exposures.
[top] Because harbor seals typically inhabit areas closer to shore rather than distances represented by the largest Level B harassment zone (39,811 m), NMFS determined that the method
Additionally, during impact pile driving of 42-inch piles, the Level A harassment isopleth is larger than the Level B harassment isopleth. Estimated take by Level A harassment during these activities results in 70.2 based on 0.45 harbor seal × 1 group × 156 hours.
Takes by Level B harassment were modified to deduct the proposed amount of take by Level A harassment ( i.e., 495-106-70 = 319 takes by Level B harassment). Therefore, NMFS proposes to authorize 176 takes by Level A harassment and 319 takes by Level B harassment for harbor seal, for a total of 495 takes. See table 7 for all proposed take numbers, by species, and the respective amount of the population that take represents.
| Species | Stock | Proposed authorized take | Level B harassment | Level A harassment | Proposed take as a percentage of stock abundance |
|---|---|---|---|---|---|
| Fin whale | Northeast Pacific | 14 | 7 | <1 | |
| Humpback whale | Western North Pacific | 3 | 1 | <1 | |
| Mexico-North Pacific | 10 | 2 | 1.3 | ||
| Hawai'i | 118 | 20 | <1 | ||
| Minke whale | Alaska | 5 | 3 | <1 | |
| Sperm whale | North Pacific | 40 | 0 | 16.2 | |
| Baird's beaked whale | Alaska | 10 | 0 | (*) | |
| Stejneger's beaked whale | Alaska | 8 | 0 | (*) | |
| Killer whale | ENP Alaska Resident | 176 | 0 | 9.1 | |
| ENP Gulf of Alaska, Aleutian Islands, and Bering Sea | 30 | ||||
| Dall's porpoise | Alaska | 21 | 19 | <1 | |
| Harbor porpoise | Bering Sea | 9 | 6 | <1 | |
| Northern fur seal | Eastern Pacific | 5 | <1 | ||
| Steller sea lion | Western, U.S | 89 | 10 | <1 | |
| Harbor seal | Aleutian Islands | 319 | 176 | 9.0 |
Description of Proposed Mitigation, Monitoring and Reporting Measures
The proposed mitigation, monitoring, and reporting measures are nearly identical to those included in the Federal Register notice announcing the final 2024 IHA (89 FR 17423, May 15, 2024), and the discussion of the least practicable adverse impact included in that document remains accurate. The only change is to the size of the shutdown zones, which have been revised in accordance with the updated Level A harassment isopleths calculated using the 2024 Technical Guidance. Additionally, shutdown zones for low-frequency cetaceans are decreased to 1,000 m from 2,100-2,600 m during impact and DTH activities to address issues with observability. During 2024 activities, USAF reported that PSO's were unable to reliably observe for LF cetaceans at the Level A harassment isopleth due to excessively foggy conditions. The measures proposed for inclusion in this authorization are found below.
Establishment of Shutdown Zone -For all pile driving/removal and DTH activities, USAF would implement shutdowns within designated zones. 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 mammal (or in anticipation of an animal entering the defined area). Shutdown zones vary based on the activity type and marine mammal hearing group (table 8). In most cases, the shutdown zones are based on the estimated Level A harassment isopleth distances for each hearing group. However, in cases where it would be challenging to detect marine mammals at the Level A harassment isopleth, smaller shutdown zones have been proposed (table 8). Additionally, per the 2024 IHA, the USAF would implement a minimum shutdown zone of 25 m during all pile driving and removal activities and DTH.
Construction supervisors and crews, PSOs, and relevant USAF staff must avoid 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 avoid direct physical interaction. If an activity is delayed or halted due to the presence of a marine mammal, the activity may not commence or resume until either the animal has voluntarily exited and been visually confirmed beyond the shutdown zone indicated in table 8 or 15 minutes have passed for delphinids or pinnipeds or 30 minutes for all other species without re-detection of the animal.
[top] Construction activities must be halted upon observation of 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 entering or within the harassment zone.
| Activity | Pile diameter | Shutdown zones | LF | HF | VHF | PW | OW |
|---|---|---|---|---|---|---|---|
| Vibratory Installation and Removal | 42-in 30-in | 50 25 | 50 25 | 50 25 | 60 30 | 50 25 | |
| DTH | 42-in | 1,000 | 350 | 500 | 400 | 400 | |
| 30-in | 290 | ||||||
| Impact | 42-in | 260 | |||||
| 30-in | 120 |
Protected Species Observers -The number and placement of PSOs during all construction activities (described in the Visual Marine Mammal Observation section) would ensure that the entire shutdown zone is visible. USAF would employ at least two PSOs for all pile driving and DTH activities.
Monitoring for Level B Harassment -PSOs would monitor the shutdown zones and beyond to the extent that PSOs can see. Monitoring beyond the shutdown zones enables observers to be aware of and communicate the presence of marine mammals in the project areas outside the shutdown zones and thus prepare for a potential cessation of activity should the animal enter the shutdown zone. If a marine mammal enters the Level B harassment zone, PSOs will document the marine mammal's presence and behavior.
Pre and Post-Activity Monitoring -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, Level A harassment, and Level B harassment for a period of 30 minutes. 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. If the shutdown zone is obscured by fog or poor lighting conditions, in-water construction activity will not be initiated until the entire shutdown zone is visible. Pile driving may commence following 30 minutes of observation when the determination is made that the shutdown zones are clear of marine mammals. If a marine mammal is observed entering or within shutdown zones, pile driving activity must be delayed or halted. If pile driving is delayed or halted due to the presence of a marine mammal, the activity may not commence or resume until either the animal has voluntarily exited and been visually confirmed beyond the shutdown zone or 15 minutes have passed for delphinids or pinnipeds or 30 minutes have passed for all other species without re-detection of the animal. If a marine mammal for which Level B harassment take is authorized is present in the Level B harassment zone, activities would begin and Level B harassment take would be recorded.
Soft Start -The use of soft-start procedures are believed to provide additional protection to marine mammals by providing warning and/or giving marine mammals a chance to leave the area prior to the hammer operating at full capacity. For impact pile driving, contractors would be required to provide an initial set of three strikes from the hammer at reduced energy, with each strike followed by a 30-second waiting period. This procedure would be conducted a total of three times before impact pile driving begins. 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 is not required during vibratory pile driving and removal activities.
Visual Marine Mammal Observation -Monitoring must be conducted by qualified marine mammal observers (MMOs), who are trained biologists, with minimum qualifications described in the Federal Register notice of the issuance of the 2024 IHA (89 FR 17423, March 11, 2024). In order to effectively monitor the pile driving monitoring zones, two trained PSOs must be positioned at the best practical vantage point(s) as described in the Federal Register notice of the issuance of the 2024 IHA. PSOs shall record specific information on the sighting forms as described in the Federal Register notice of the issuance of the 2024 IHA. At the conclusion of the in-water construction work, USAF will provide NMFS with a monitoring report that includes information described in the 2024 IHA Federal Register Notice.
Preliminary Determinations
USAF proposes to conduct activities nearly identical to those covered in the previous 2024 IHA. We have revised the Level A harassment and mitigation zones to incorporate and address the 2024 Technical Guidance, which results in different Level A harassment isopleths.
When issuing the 2024 IHA, NMFS found the EAS Fuel Pier repair project, in its entirety, would have a negligible impact to species or stocks' rates of recruitment and survival and the amount of taking would be small relative to the population size of such species or stock (less than 3 percent for all stocks except sperm whale, killer whale, and harbor seal, which are less than 30 percent). As described above, the total number of takes proposed for authorization for each stock are the same as the takes authorized in the 2024. In cases where take by Level A harassment has increased, it has only increased a small amount (proposed take by Level A harassment has increased by 4 for fin whale, by 6 for Dall's porpoise, by 1 for harbor porpoise, and by 21 by harbor seal. While no take by Level A harassment was authorized under the 2024 IHA for Steller sea lion and northern fur seal, only a small amount is proposed for authorization through this IHA. The anticipated impacts from the project are similar to those previously analyzed. The proposed IHA includes the same monitoring, and reporting measures as the 2024 IHA and the shutdown zones have been revised to address the new Level A harassment isopleths calculated from the 2024 technical guidance. In conclusion, there is no new information suggesting that our analysis or findings should change.
[top] Based on the information contained here and in the referenced documents, NMFS has preliminarily determined the following: (1) the required mitigation measures will effect the least practicable impact on marine mammal species or stocks and their habitat; (2) the proposed authorized takes will have a negligible impact on the affected marine mammal species or stocks; (3) the proposed authorized takes represent small numbers of marine mammals relative to the affected stock abundances; (4) USAF's activities will not have an unmitigable adverse impact
Endangered Species Act (ESA)
Section 7(a)(2) of the 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, in this case with the Alaska Regional Office.
On March 1, 2024, NMFS Alaska Regional Office completed consultation with NMFS Office of Protected Resources (OPR) for the 2024 EAS Fuel Pier Repair project and issued a Biological Opinion, which concluded that the take NMFS proposed to authorize through IHAs would not jeopardize the continued existence of any endangered or threatened species or destroy or adversely modify any designated critical habitat.
NMFS is proposing to authorize take of western Distinct Population Segment (DPS) Steller sea lion, fin whale (northeast Pacific), humpback whale (Mexico-North Pacific and western North Pacific), and sperm whale (North Pacific) which are listed under the ESA. The In the March 1, 2024 Biological Opinion, reinitiation clause (3), states that formal consultation should be reinitiated if "the agency action is subsequently modified in a manner that causes an effect on the listed species or critical habitat not considered in this biological opinion." Given the additional take by Level B harassment of humpback whale (Western N Pacific DPS) and Level A harassment of Western DPS Steller sea lion and fin whale that NMFS OPR proposes to authorize, as described herein, NMFS has reinitiated consultation internally on the issuance of this proposed IHA under section 101(a)(5)(D) of the MMPA. NMFS will conclude the ESA consultation prior to reaching a determination regarding the proposed issuance of the authorization.
Proposed Authorization
As a result of these preliminary determinations, NMFS proposes to issue an IHA to USAF for conducting the EAS Fuel Pier Repair in Alcan Harbor on Shemya Island, Alaska between April through October 2024, provided the previously mentioned mitigation, monitoring, and reporting requirements are incorporated. A draft of the proposed IHA can be found at https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act.
Request for Public Comments
We request comment on our analyses (included in both this document and the referenced documents supporting the 2024 IHA), the proposed authorization, and any other aspect of this notice of proposed IHA for the Eareckson Air Station Fuel Pier Repair project. We also request comment on the potential for renewal of this proposed IHA as described in the paragraph below. Please include with your comments any supporting data or literature citations to help inform our final decision on the request for MMPA authorization.
On a case-by-case basis, NMFS may issue a one-time, 1-year renewal IHA following notice to the public providing an additional 15 days for public comments when (1) up to another year of identical or nearly identical, or nearly identical, activities as described in the Description of the Proposed Activity and Anticipated Impacts section of this notice is planned or (2) the activities as described in the Description of the Proposed Activity and Anticipated Impacts section of this notice would not be completed by the time the IHA expires and a renewal would allow for completion of the activities beyond that described in the Description of the Proposed Activity and Anticipated Impacts section of this notice, provided all of the following conditions are met:
• A request for renewal is received no later than 60 days prior to the needed renewal IHA effective date (recognizing that the renewal IHA expiration date cannot extend beyond one year from expiration of the initial IHA);
• The request for renewal must include the following: (1) An explanation that the activities to be conducted under the requested renewal IHA are identical to the activities analyzed under the initial IHA, are a subset of the activities, or include changes so minor ( e.g., reduction in pile size) that the changes do not affect the previous analyses, mitigation and monitoring requirements, or take estimates (with the exception of reducing the type or amount of take); and (2) A preliminary monitoring report showing the results of the required monitoring to date and an explanation showing that the monitoring results do not indicate impacts of a scale or nature not previously analyzed or authorized; and
• Upon review of the request for renewal, the status of the affected species or stocks, and any other pertinent information, NMFS determines that there are no more than minor changes in the activities, the mitigation and monitoring measures will remain the same and appropriate, and the findings in the initial IHA remain valid.
Dated: March 7, 2025.
Kimberly Damon-Randall,
Director, Office of Protected Resources, National Marine Fisheries Service.
[FR Doc. 2025-03953 Filed 3-12-25; 8:45 am]
BILLING CODE 3510-22-P