90 FR 91 pgs. 20283-20291 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Pile Driving Training Exercises at Naval Base Ventura County, Port Hueneme
Type: NOTICEVolume: 90Number: 91Pages: 20283 - 20291
Pages: 20283, 20284, 20285, 20286, 20287, 20288, 20289, 20290, 20291Docket number: [RTID 0648-XE500]
FR document: [FR Doc. 2025-08357 Filed 5-12-25; 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-XE500]
Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Pile Driving Training Exercises at Naval Base Ventura County, Port Hueneme
AGENCY:
[top] National Marine Fisheries Service (NMFS), National Oceanic and
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 the United States Navy (Navy) to incidentally harass marine mammals during construction activities associated with pile driving training exercises at Naval Base Ventura County, Port Hueneme (NBVC). The Navy's activities are considered military readiness activities pursuant to the MMPA, as amended by the National Defense Authorization Act for Fiscal Year 2004 (NDAA).
DATES:
This authorization is effective from May 12, 2025, through December 31, 2025.
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-military-readiness-activities. In case of problems accessing these documents, please call the contact listed below.
FOR FURTHER INFORMATION CONTACT:
Alyssa Clevenstine, 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 issued or, if the taking is limited to harassment, a notice of a proposed incidental take authorization may be provided to the public for review.
Authorization for incidental takings shall be granted if NMFS finds that the taking will have a negligible impact on the species or stock(s) and will not have an unmitigable adverse impact on the availability of the species or stock(s) for taking for subsistence uses (where relevant). Further, NMFS must prescribe the permissible methods of taking and other "means of effecting the least practicable adverse impact" on the affected species or stocks and their habitat, paying particular attention to rookeries, mating grounds, and areas of similar significance, and on the availability of such species or stocks for taking for certain subsistence uses (referred to in shorthand as "mitigation"); and requirements pertaining to the mitigation, monitoring and reporting of such takings are set forth.
The NDAA (Pub. L. 108-136) removed the "small numbers" and "specified geographical region" limitations indicated above and amended the definition of "harassment" as it applies to a "military readiness activity." The activity for which incidental take of marine mammals is being requested addressed here qualifies as a military readiness activity.
History of Request
On May 13, 2024, the Navy submitted an application requesting issuance of an IHA authorizing take of California sea lions ( Zalophus californianus ) and harbor seals ( Phoca vitulina richardii ), by Level B harassment only, incidental to four pile driving training exercises at NBVC. Revised applications were received on August 6, 2024, and September 12, 2024. The application was deemed adequate and complete on September 24, 2024, and the notice of the proposed IHA was published in the Federal Register on October 23, 2024 (89 FR 84534). A correction to this notice was published on October 30, 2024, that clarified the appropriate public comment duration period ( i.e., 30 days) (89 FR 86320). On April 15, 2025, the Navy submitted a memo with updated information and clarification on revised pile driving training needs to account for exercises planned through December 31, 2025.
Changes from the 2023 IHA include those associated with the Navy's request, in some instances, to install and remove additional piles and types of piles during the training exercises over additional days ( i.e., more than were addressed in the 2023 IHA) due to emergent training requirements and tempo (see the Description of the Specified Activities section for more details). In addition, on October 24, 2024, NMFS published its Updated Technical Guidance for Assessing the Effects of Anthropogenic Sound on Marine Mammal Hearing (Version 3.0) (89 FR 84872, NMFS (2024)), which includes updated hearing ranges and names for marine mammal hearing groups as well as updated thresholds and weighting functions to inform auditory injury estimates ( i.e., for Level A harassment) that have been applied in NMFS' analysis herein. These changes do not affect the previous analyses, mitigation, and monitoring requirements, or method of take calculations, outside of the inclusion of slightly larger Level A harassment zones and shutdown zones due to the increased numbers of piles anticipated to be installed and or removed within a day, and that the planned training exercises would be completed in 160 days instead of 96 days. In evaluating the current request and to the extent deemed appropriate, NMFS relied on the information presented in notices associated with the issuance of the initial 2023 IHA (88 FR 15956, March 15, 2023; 88 FR 28517, May 4, 2023).
The Navy submitted a monitoring report on March 4, 2023, based on the work completed under the 2023 IHA, which confirms that the applicant implemented the required mitigation and monitoring during the initial year of the activity, and that they did not exceed the authorized levels of take under the 2023 IHA. These monitoring results, as well as the Navy's current request and application, are available to the public on our website: https://www.fisheries.noaa.gov/action/incidental-take-authorization-us-navy-pile-training-exercises-naval-base-ventura-county-port.
Description of the Specified Activities
The primary mission of NBVC is to provide a home port and to furnish training, administrative, and logistical support for the Naval Construction Battalions. As described in the 2023 IHA, Naval Construction Group ONE proposes to execute pile driving training exercises at NBVC that are essential to construction battalion personnel prior to deployment. The specific components of each exercise could vary based on the specific training requirements for each battalion, but could include vibratory and impact pile driving, temporary pier construction, and subsequent removal of all installed materials. These are military readiness activities, as defined under the NDAA of Fiscal Year 2004 (Pub. L. 108-136).
[top] Under the 2023 IHA, the Navy requested take by Level B harassment for California sea lions and harbor seals incidental to up to four pile driving training exercises, each of which could include installation and removal of a sheet pile wall and round pile pier. Level A harassment was not anticipated, requested, or authorized. It was estimated that each training exercise could take up to 24 days (12 days for pile installation and 12 days for pile
A detailed description of the planned training activities is provided in the Federal Register notice for the proposed IHA (89 FR 84534, October 23, 2024), as well as in the documents related to the 2023 IHA ( i.e., the Federal Register notice of the proposed 2023 IHA (88 FR 15956, March 15, 2023), the Federal Register notice of issuance of the 2023 IHA (88 FR 28517, May 4, 2023), and all associated references and documents). Only minor changes have been made to the planned activities since the publication of those documents. Therefore, a description is provided below. Please refer to those documents for the description of the specific activity. We also refer the reader to the Navy's previous and current applications and monitoring reports which can be found at: https://www.fisheries.noaa.gov/action/incidental-take-authorization-us-navy-pile-training-exercises-naval-base-ventura-county-port.
Comments and Responses
A notice of NMFS' proposal to issue an IHA to the Navy was published in the Federal Register on October 23, 2024 (89 FR 84534). That notice and the Federal Register notices related to the initial 2023 IHA (88 FR 15956, March 15, 2023; 88 FR 28517, May 4, 2023) described, in detail, the Navy's activity, the marine mammal species that may be affected by the activity, and the anticipated effects on marine mammals. In the proposed notice for this 2025 IHA (89 FR 84534, October 23, 2024), 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 public comments.
Changes From the Proposed IHA to Final IHA
There are minor changes from the proposed IHA to the final IHA, including the addition of a new pile type (16-inch plastic pile), decrease in time to install and remove timber and sheet piles by vibratory methods, decrease in days of installation and total days per exercise for timber and H-beam piles, increase in buffer days per exercise (table 1), and changes to calculated distances and areas to the estimated Level A and Level B harassment thresholds (table 5), resulting in changes to the Level A harassment shutdown zones and Level B harassment monitoring zones for all activities (table 7). These changes do not affect the estimated take amounts, and no changes have been made to the authorized take (table 6). These changes are incorporated herein but do not change any of the analyses or determinations from the proposed IHA (89 FR 84534, October 23, 2024).
| Pile size/type/shape | Number of sheets/ piles | Vibratory installation/ removal duration per pile | Potential impact strikes per pile, if needed | Production rate (piles/day) | Installation | Vibratory hammer | Impact hammer | Removal | Vibratory hammer | Impact hammer | Days of installation | Days of removal | Buffer days? a | Total days per exercise |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 24-in Steel Sheet | 30 | 7/7 minutes | N/A | 30 | N/A | 30 | N/A | 1 | 1 | 12 | 14 | |||
| 16-in Timber Pile | 12 | 10/7 minutes | 1,800 | 12 | 6 | 12 | N/A | 1 | 1 | 7 | 9 | |||
| 14-in H-Beam Pile | 6 | 20/30 minutes | 1,800 | 6 | 2 | 6 | N/A | 1 | 1 | 6 | 8 | |||
| 16-inch Plastic Pile | 12 | 5/5 minutes | 500 | 12 | 6 | 12 | N/A | 1 | 1 | 7 | 9 | |||
| Totals | 21.25 hours/22.25 hours | 4 | 4 | 32 | 40 | |||||||||
| a ?Buffer days are included in this 2025 IHA to allow for unanticipated variation in production rates and to account for any training that is slowed or delayed due to the need to meet specific training or mitigation requirements; buffer days were not considered in the initial 2023 IHA. | ||||||||||||||
Description of Marine Mammals
A description of the marine mammals in the area of the activities for which take is authorized here, including information on abundance, status, distribution, and hearing, may be found in the Federal Register notice of the proposed IHA (88 FR 15956, March 15, 2023) for the initial 2023 authorization. NMFS has reviewed the monitoring data from the 2023 IHA, 2024 draft stock assessment reports, information on relevant unusual mortality events, and other scientific literature, and determined there is no new information that affects which species or stocks have the potential to be affected or the pertinent information in the Description of the Marine Mammals in the Area of Specified Activities contained in the supporting documents for the 2023 IHA.
Marine Mammal Hearing
[top] 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
| 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 of Specified Activities on Marine Mammals and Their Habitat
The effects of underwater noise from the Navy's training activities have the potential to result in behavioral harassment of marine mammals in the vicinity of NBVC. The notice of the 2023 proposed IHA (88 FR 15956, March 15, 2023) included a discussion of the effects of anthropogenic noise on marine mammals and the potential effects of underwater noise from the Navy's training activities on marine mammals and their habitat. That information and analysis is referenced in this final IHA determination and is not repeated here; please refer to the notice of the 2023 proposed IHA (88 FR 15956, March 15, 2023). NMFS has reviewed the monitoring data from the 2023 IHA, recent draft stock assessment reports, information on relevant unusual mortality events, and other scientific literature, and determined that there is no new information that affects our initial analysis of impacts on marine mammals and their habitat.
Estimated Take of Marine Mammals
A detailed description of the methods and inputs used to estimate take for the specified activity are found in the Federal Register notices of the proposed and final IHAs for the 2023 authorization (88 FR 15956, March 15, 2023; 88 FR 28517, May 4, 2023). Specifically, the source levels and marine mammal occurrence data applicable to this authorization remain unchanged from the 2023 IHA, as do the thresholds and methodology for estimating take by Level B harassment.
The Navy, however, anticipates that the number of piles that could be installed or removed per day will increase compared to the 2023 IHA so that personnel can meet new training requirements during the IHA authorization period (see table 1). In addition, the Navy anticipates that the vibratory removal of 24-in steel sheets could take 30 minutes, whereas the 2023 IHA considered this activity could take 20 minutes. As described in the Federal Register notices of the proposed and final IHAs for the 2023 authorization (88 FR 15956, March 15, 2023; 88 FR 28517, May 4, 2023), the ensonified area associated with Level A harassment accounts for both source level of the specified activity and duration of that activity. Increasing the number of piles to be installed/removed per day, as well as the anticipated duration of vibratory removal of steel sheet piles, increases the total estimated daily duration of the activity, and thus, the extent of the Level A harassment zones. Note; the estimated distances to the Level B harassment isopleths do not increase because activity duration is not considered in their calculation.
In the notice of this proposed IHA (89 FR 84534, October 23, 2024), we provided calculations using the NMFS' 2024 Updated Technical Guidance for the purposes of understanding the number of potential takes by Level A harassment in comparison to NMFS' 2018 Technical Guidance;); since that time the Updated Technical Guidance has been finalized and is thus only considered herein (89 FR 84872, October 24, 2024)). The NMFS' 2024 Updated Technical Guidance criteria include both updated thresholds and updated weighting functions for each hearing group to inform auditory injury estimates (89 FR 36762). The thresholds are provided in table 3. The references, analysis, and methodology used in the development of the criteria, as well as the detailed description of the updated weighting functions, are described in the NMFS' 2024 Updated Technical Guidance, which may be accessed at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.
[top] The Navy's training activities include the use of impulsive (impact pile driving) and non-impulsive (vibratory driving) sources.
| Hearing group | AUD INJ onset acoustic 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,HF,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 criteria for impulsive sounds: Use whichever criteria 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 criteria associated with impulsive sounds, the Peak sound pressure level (PK SPL) criteria are recommended for consideration for non-impulsive sources. | |||
| Note: Peak sound pressure ( 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 1 µPa 2 s. In this table, criteria are abbreviated to be more reflective of International Organization for Standardization (ISO) standards (ISO 2017; ISO 2020). The subscript "flat" is being included to indicate peak sound pressure are flat weighted or unweighted within the generalized hearing range of marine mammals underwater ( i.e., 7 hertz (Hz) to 165 kHz). The subscript associated with cumulative sound exposure level criteria 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 criteria 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 criteria will be exceeded. | |||
NMFS developed optional User Spreadsheet tools to accompany the 2024 Updated 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 these optional tools, 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, these optional tools offers the best way to estimate isopleth distances when more sophisticated modeling methods are not available or practical. For stationary sources, such as vibratory and impact pile driving, the optional User Spreadsheet tools predict the distance at which, if a marine mammal remained at that distance for the duration of the activity, it will be expected to incur permanent AUD INJ. Inputs used in the optional User Spreadsheet tools based on the Navy's request are reported in table 4. The isopleths calculated for this IHA based on NMFS' 2024 Updated Technical Guidance are reported in table 5.
| Pile size and type | Vibratory pile driving | 16-inch Plastic Piles | 16-inch Timber Piles | 14-inch Steel H Beam | 24-inch Steel Sheet | Impact pile driving | 16-inch Plastic Piles | 16-inch Timber Piles | 14-inch Steel H Beam | 24-inch Steel Sheet |
|---|---|---|---|---|---|---|---|---|---|---|
| Source Level | 162 dB RMS | 162 dB RMS | 147 dB RMS | 159 dB RMS | 170 dB SEL | 160 dB SEL | 170 dB SEL | N/A | ||
| Transmission Loss Coefficient | 15 | 15 | 15 | 15 | 15 | 15 | 15 | N/A | ||
| Weighting Factor Adjustment (kHz) | 2.5 | 2.5 | 2.5 | 2.5 | 2 | 2 | 2 | N/A | ||
| Time to install/remove single pile (minutes) | 5/5 | 10/7 | 30/30 | 7/7 | N/A | N/A | N/A | N/A | ||
| Number of strikes per pile | N/A | N/A | N/A | N/A | 500 | 1,800 | 1,800 | N/A | ||
| Piles to install/remove per day | 12/12 | 12 | 6 | 30 | 6 | 6 | 2 | N/A | ||
| Distance of sound pressure level measurement (meters) | 10 | 10 | 10 | 11 | 10 | 10 | 10 | N/A |
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| Activity | Pile description | Piles per day | Level A harassment distances (m) | PW | OW | Level A harassment areas (km 2 ) for all hearing groups? a | Level B harassment distance (m) all hearing groups? b | Level B harassment areas (km 2 ) for all hearing groups? a |
|---|---|---|---|---|---|---|---|---|
| Vibratory Installation/Removal | 16-inch Timber Piles | 12 | 22.0 | 7.4 | <0.1 | 790 | <0.3 | |
| 16-inch Plastic Piles | 12 | 13.8 | 4.7 | <0.1 | 790 | <0.3 | ||
| 14-inch Steel H Beam | 6 | 2.9 | 1.0 | <0.1 | 631 | <0.3 | ||
| 24-inch Steel Sheet | 30 | 20.1 | 6.8 | <0.1 | 790 | <0.3 | ||
| Impact Installation | 16-inch Timber Piles | 6 | 126.5 | 47.1 | <0.1 | 47 | <0.1 | |
| 16-inch Plastic Piles | 6 | 249.9 | 93.2 | <0.1 | 790 | <0.3 | ||
| 14-inch Steel H-Beam | 2 | 282.2 | 105.2 | <0.1 | 790 | <0.3 | ||
| a ?Harassment areas have been truncated where appropriate to account for land masses. | ||||||||
| b ?The maximum harassment distances are approximately 790 m for Wharf 4 South, 795 m for Wharf 4 East, and 655 m for Wharf D due to the presence of land masses in the project area, which truncate sound transmission. | ||||||||
The stocks taken, methods of take, and types of take remain unchanged from the 2023 authorization. Here, we estimate the amount of taking by Level B harassment for both species using the same method and rates of daily occurrence for California sea lions (342 individuals) and harbor seals (21 individuals) used in the 2023 IHA, applied across the 160 days of anticipated activity, resulting in 46,512 and 2,856 instances of take by Level B harassment, respectively (table 6). While the estimated distances to the Level A harassment thresholds and the shutdown zones are in some cases larger than the estimated distances to the Level B harassment thresholds (see distances for impact driving in table 5), they are still relatively small ( i.e., less than 283 m based on NMFS' 2024 Updated Technical Guidance) and it is unlikely that an individual would remain in these zones long enough to incur AUD INJ. Further, we anticipate that the Navy will be able to effectively shut down operations as necessary to avoid any take by Level A harassment. Therefore, take by Level A harassment is not authorized.
| Species | Stock | Authorized amount of taking | Level A | Level B | Total | Percent of stock |
|---|---|---|---|---|---|---|
| California Sea Lion | U.S. | 0 | 46,512 | 46,512 | 18.05 | |
| Harbor Seal | California | 0 | 2,856 | 2,856 | 9.22 |
Description of Mitigation, Monitoring and Reporting Measures
The mitigation, monitoring, and reporting measures included as requirements in this authorization are identical to those included in the Federal Register notice announcing the issuance of the 2023 IHA (88 FR 28517, May 4, 2023), except for the size of the respective shutdown zones as discussed below, and the discussion of the least practicable adverse impact included in that document remains accurate. The IHA includes the following measures:
• The Navy will conduct briefings between supervisors and trainees, the marine mammal monitoring team, and Navy staff prior to the start of all in-water pile driving activity, and when new personnel join the work, to ensure that responsibilities, communication procedures, marine mammal monitoring protocols, and operational procedures are clearly understood.
• During all in-water work other than pile driving ( e.g., pile placement, boat use), in order to prevent injury from physical interaction with construction equipment, a shutdown zone of 10 m (32.8 ft) will be implemented. If a marine mammal comes within 10 m (32.8 ft), operations will cease and vessels will reduce speed to the minimum level required to maintain steerage and safe working conditions. If human safety is at risk, the in-water activity will be allowed to continue until it is safe to stop.
• The Navy will establish shutdown zones for all for in-water pile driving activities. The purpose of a shutdown zone is generally to define an area within which shutdown of activity will occur upon sighting of a marine mammal (or in anticipation of an animal entering the defined area). Shutdown zones will vary based on the type of pile installation/removal activity, but are larger than the calculated Level A harassment isopleths shown in table 7. The shutdown zones have increased slightly from what was required in the 2023 IHA based on the Navy's request to increase the number of piles that may be installed and or removed each day, and in the case of 24-in steel sheets, the longer duration estimated to remove piles with a vibratory hammer (see table 1). The placement of lookouts during all pile driving activities (described in detail in below) will ensure that the entirety of all shutdown zones and Level A harassment zones are visible during pile installation and removal.
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| Activity | Pile description | Distance (m) | PW | OW |
|---|---|---|---|---|
| Vibratory Installation/Removal | 16-inch Timber Piles | 25 | 25 | |
| 16-inch Plastic Piles | 25 | 25 | ||
| 14-inch Steel H Beam | 25 | 25 | ||
| 24-inch Steel Sheet | 25 | 25 | ||
| Impact Installation | 16-inch Timber Piles | 130 | 130 | |
| 16-inch Plastic Piles | 260 | 260 | ||
| 14-inch Steel H-Beam | 290 | 290 |
• The Navy will delay or shutdown all in-water pile driving activities should an animal approach or enter the appropriate shutdown zone. The Navy can resume in-water pile driving activities after one of the following conditions has been met: (1) the animal is observed exiting the shutdown zone; (2) the animal is thought to have exited the shutdown zone based on a determination of its course, speed, and movement relative to the pile driving location; or (3) the shutdown zone has been clear from any additional sightings for 15 minutes.
• The Navy will employ lookouts trained in marine mammal identification and behaviors to monitor marine mammal presence in the action area. Requirements for numbers and locations of observers will be based on hammer type, pile material, and Seabees training location as described in section 5 of the IHA. Lookouts will track marine mammals observed anywhere within their visual range relative to in-water training activities, and estimate the amount of time a marine mammal spends within the Level A or Level B harassment zones while pile driving activities are underway. The Navy will monitor the project area, including the Level B harassment zones, to the maximum extent possible based on the required number of lookouts, required monitoring locations, and environmental conditions. For all pile driving and removal activities, at least one lookout will be used.
• The placement of the lookouts during all pile driving and removal activities will ensure that the entire applicable shutdown zones are visible during all in-water pile installation and removal. One observer will be placed in a position to implement shutdown/delay procedures, when applicable, by notifying the hammer operator of a need for a shutdown of pile driving or removal.
• Prior to the start of pile driving or removal, the shutdown zone(s) will be monitored for a minimum of 30 minutes to ensure that they are clear of marine mammals ( i.e., pre-clearance monitoring). Pile driving will only commence once observers have declared the shutdown zone(s) are clear of marine mammals. Monitoring will also take place for 30 minutes post-completion of pile driving.
• If in-water work ceases for more than 30 minutes, the Navy will conduct pre-clearance monitoring of both the Level B harassment zone and shutdown zone.
• Pre-start clearance monitoring will be conducted during periods of visibility sufficient for the lead lookout to determine that the shutdown zones indicated in table 7 are clear of marine mammals. Pile driving can commence following 30 minutes of observation when the determination is made that the shutdown zones are clear of marine mammals.
• The Navy will use soft start techniques when impact pile driving. Soft start requires contractors to provide an initial set of three strikes at reduced energy, followed by a 30-second waiting period, then two subsequent reduced energy strike sets. A soft start 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. Soft starts will not be used for vibratory pile installation and removal. Lookouts will begin observing for marine mammals 30 minutes before "soft start" or in-water pile installation or removal begins.
• For any marine mammal species for which take by Level B harassment has not been authorized, in-water pile installation/removal will shut down immediately when the animals are sighted.
• If take by Level B harassment reaches the authorized limit for an authorized species, pile installation will be stopped as these species approach the Level B harassment zone to avoid additional take of them.
• Monitoring will be conducted by qualified lookouts with support from Navy biologists, in accordance with the following:
• Navy biologists will train and certify lookouts in accordance with the mitigation, monitoring and reporting requirements of the issued IHA;
• All lookouts will maintain contact via either handheld communication devices or flags to signal sightings and shutdowns;
• Lookouts will be placed at vantage points to monitor for marine mammals and implement shutdown/delay procedures when applicable by calling for the shutdown to the hammer operator;
• The Lead lookout will be located within auditory range of the pile driving team and will have primary responsibility for calling activity shutdowns;
• Lookouts will use a hand-held global positioning device (GPS) device, rangefinder, visual reference points, or marker buoy to verify the required monitoring distance from the project site;
• Monitoring will occur in all-weather until training has concluded for the day;
• Lookouts will scan the waters within the Level A harassment and Level B harassment zones using binoculars (10x42 or similar) and or the naked eye and make visual observations of marine mammals present; and
• Lookouts will record all observations of marine mammals as described in the section 5 of the IHA, regardless of distance from the pile being driven. Lookouts will document any behavioral reactions in concert with distance from piles being driven or removed.
• Lookouts will have the following additional qualifications:
• Visual acuity in both eyes (correction is permissible) sufficient for discernment of moving targets at the water's surface with ability to estimate target size and distance; use of binoculars may be necessary to correctly identify the target;
• 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.
The Navy will submit a draft marine mammal monitoring report to NMFS within 90 days after the completion of pile driving training activities, or 60 days prior to a requested date of issuance of any future IHAs for projects at the same location, whichever comes first. NMFS will provide comments within 30 days after receiving the draft report, and the Navy will address the comments and submit revisions within 30 days of receipt. If no comments are received from NMFS within 30 days, the draft report will be considered as final.
The draft and final marine mammal monitoring reports will be submitted to PR.ITP.MonitoringReports@noaa.gov and itp.clevenstine@noaa.gov. The reports must include an overall description of work completed, a narrative regarding marine mammal sightings, and associated data sheets. Specifically, the reports must include:
• Dates and times (begin and end) of all marine mammal monitoring;
• Training activities occurring during each daily observation period, including the number and type of piles driven or removed and by what method ( i.e., impact or vibratory) and the total equipment duration for vibratory installation and removal for each pile or estimated total number of strikes for each pile for impact driving;
• Lookout locations during marine mammal monitoring;
• Environmental conditions during monitoring periods (at beginning and end of lookout 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;
• Description of any deviation from initial proposal in pile numbers, pile types, average driving times, etc. ;
• Brief description of any impediments to obtaining reliable observations during training periods; and
• Description of any impediments to complying with the aforementioned mitigation measures.
Lookouts must record all incidents of marine mammal occurrence in the area in which take is anticipated regardless of distance from activity, and must document any behavioral reactions in concert with distance from piles being driven or removed. Specifically, lookouts must record the following:
• Name of lookout who sighted the animal(s) and lookout location and activity at time of sighting;
• Time of sighting;
• Identification of the animal(s) ( e.g., genus/species, lowest possible taxonomic level, or unidentified), lookout confidence in identification, and the composition of the group if there is a mix of species;
• 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);
• Estimated number of animals (min/max/best estimate);
• Estimated number of animals by cohort (adults, juveniles, neonates, group composition, sex class, etc. );
• Animal's closest point of approach and estimated time spent within the harassment zone;
• 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 and shutdown zones, by species; and
• 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.
Determinations
The 2025 IHA consists of the same activities analyzed through the initial 2023 authorization. The 2025 IHA authorizes the incidental take by Level B harassment of California sea lions and harbor seals to up to four 40-day pile driving training exercises. The Navy requested a new IHA so that it can conduct an additional four training exercises during the authorization period. However, due to emergent training requirements and tempo, the Navy requested, in some instances, to install and remove additional piles over additional days during the training exercises than what was analyzed in the initial 2023 IHA ( i.e., 160 total days considered in this 2025 IHA versus 96 days considered in the initial 2023 IHA), which results in an increase in the number of takes by Level B harassment authorized for harbor seals and sea lions (see table 6). In addition, on October 24, 2024, NMFS published its Updated Technical Guidance (89 FR 84872), which includes updated hearing ranges and names for marine mammal hearing groups as well as updated thresholds and weighting functions to inform auditory injury estimates ( i.e., for Level A harassment). These changes result in slightly larger Level A harassment zones and shutdown zones due to increased durations of pile driving activities. No other changes have been made to the planned activities.
In analyzing the effects of the activities for the initial 2023 IHA, NMFS determined that the Navy's activities will have a negligible impact on the affected species or stocks. There is no new information that affects NMFS' determinations supporting issuance of the initial 2023 IHA or this IHA. While the takes by Level B harassment authorized for this IHA are greater than the takes by Level B harassment authorized in the initial 2023 IHA, the anticipated impacts of the Navy's training exercises on marine mammals are the same as what was considered in the initial 2023 IHA ( e.g., temporary modifications in behaviors or temporary threshold shifts that will not result in fitness impacts to any individuals). In addition, the specified activity and ensonification areas are still very small relative to the overall habitat ranges of all species and do not include habitat areas of special significance (biologically important areas or endangered species designated critical habitat). Lastly, the intensity of anticipated takes by Level B harassment is relatively low for all stocks and will not be of a duration or intensity expected to result in impacts on reproduction or survival. The mitigation measures and monitoring and reporting requirements as described above are identical to the initial 2023 IHA, except for the requirement of slightly larger shutdown zones.
Based on the information contained here and in the referenced documents, NMFS has 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 authorized takes will have a negligible impact on the affected marine mammal species or stocks; (3) the authorized takes represent small numbers of marine mammals relative to the affected stock abundances; (4) the Navy's activities will not have an unmitigable adverse impact on taking for subsistence purposes as no relevant subsistence uses of marine mammals are implicated by this action; and (5) appropriate monitoring and reporting requirements are included.
Endangered Species Act
[top] No incidental take of Endangered Species Act (ESA)-listed species is authorized or expected to result from this activity. Therefore, NMFS has determined that formal consultation
National Environmental Policy Act
To comply with the National Environmental Policy Act of 1969 (NEPA; 42 U.S.C. 4321 et seq. ) and NOAA Administrative Order (NAO) 216-6A, NMFS must review our proposed action ( i.e., the issuance of an IHA) with respect to potential impacts on the human environment. This action is consistent with categories of activities identified in Categorical Exclusion B4 (incidental take authorizations 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 the Navy for the potential harassment of two marine mammal species incidental to pile driving training exercises at NBVC that includes the previously explained mitigation, monitoring, and reporting requirements.
Dated: May 7, 2025.
Kimberly Damon-Randall,
Director, Office of Protected Resources, National Marine Fisheries Service.
[FR Doc. 2025-08357 Filed 5-12-25; 8:45 am]
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