# Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to the Port of Alaska's North Extension Stabilization Step 1 Project in Anchorage, Alaska > Briefs, arguments, decisions, and more. URL: https://www.frixlaw.com/law-library/documents/fr%3A2024-00511 ## Record - **Collection:** Federal Register - **Document type:** Notice - **Published:** January 16, 2024 - **Citation:** 89 FR 2832 ## Text DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration [RTID 0648-XD572] Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to the Port of Alaska's North Extension Stabilization Step 1 Project in Anchorage, Alaska AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION: Notice; issuance of an incidental harassment authorization. SUMMARY: In accordance with the regulations implementing the Marine Mammal Protection Act (MMPA) as amended, notification is hereby given that NMFS has issued an incidental harassment authorization (IHA) to the Port of Alaska (POA) to incidentally harass marine mammals during construction activities associated with the North Extension Stabilization Step 1 (NES1) Project in Anchorage, Alaska. DATES: This authorization is effective from April 1, 2024, through March 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-construction-activities. In case of problems accessing these documents, please call the contact listed below. FOR FURTHER INFORMATION CONTACT: Reny Tyson Moore, 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 mitigation, monitoring and reporting of the takings are set forth. The definitions of all applicable MMPA statutory terms cited above are included in the relevant sections below. Summary of Request On July 19, 2022, NMFS received a request from the POA for an IHA to take marine mammals incidental to construction activities related to the NES1 project in Anchorage, Alaska. Following NMFS' review of the application, the POA submitted revised versions on December 27, 2022, July 28, 2023, and August 31, 2023. The application was deemed adequate and complete on September 7, 2023. The POA submitted a final version addressing additional minor corrections on September 21, 2023. The Federal Register notice of the proposed IHA and request for comments was published on November 6, 2023 (88 FR 76576). The POA's request is for take of seven species of marine mammals by Level B harassment and, for a subset of these species ( i.e., harbor seal ( Phoca vitulina ) and harbor porpoise ( Phocoena phocoena )), Level A harassment. Neither the POA nor NMFS expect serious injury or mortality to result from this activity and, therefore, an IHA is appropriate. NMFS previously issued IHAs to the POA for similar work (85 FR 19294, April 6, 2020; 86 FR 50057, September 7, 2021). The POA complied with all the requirements ( e.g., mitigation, monitoring, and reporting) of the previous IHAs, and information regarding their monitoring results may be found in the Effects of the Specified Activity on Marine Mammals and their Habitat section of the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023), the Estimated Take section in this notice of issuance, and online at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities. This IHA will cover 1-year of the ongoing Port of Alaska Modernization Program (PAMP) for which the POA obtained prior IHAs and intends to request additional take authorization for subsequent facets of the program. The PAMP involves construction activities related to the modernization of the POA's marine terminals. Description of Specified Activity The POA, located on Knik Arm in upper Cook Inlet, provides critical infrastructure for the citizens of Anchorage and a majority of the citizens of Alaska. The North Extension at the POA is a failed bulkhead structure that was constructed between 2005 and 2011. Parts of the North Extension bulkhead structure and the surrounding upland area are unstable and collapsing, and some of the sheet piles are visibly twisted and buckled. The structure presents safety hazards and logistical impediments to ongoing Port operations, and much of the upland area is currently unusable. The North Extension Stabilization (NES) project will result in removal of the failed sheet pile structure and reconfiguration and realignment of the shoreline within the North Extension, including the conversion of approximately 0.05 square kilometers (km 2 ; 13 acres) of developed land back to intertidal and subtidal habitat within Knik Arm. The NES project will be completed in two distinct steps, NES1 and NES2, separated by multiple years and separate permitting efforts. This notice is applicable to an IHA for the incidental take of marine mammals during in-water construction associated with NES1. The NES1 project will involve the removal of portions of the failed sheet pile structure to stabilize the North Extension. The NES1 project will remove approximately half of the North Extension structure extending approximately 274-meters (m) north from the southern end of the North Extension. This project will also stabilize the remaining portion of the North Extension by creating an end-state embankment. While the majority of the Project will be demolition work, the term “construction” as used herein refers to both construction and demolition work. In-water construction associated with this project includes vibratory installation and removal of 81 24-inch (61-centimeter (cm)) or 36-inch (91-cm) temporary steel pipe stability template piles as well as vibratory removal, splitting (via a sheet pile splitter used in conjunction with a vibratory hammer), pile cutting (via hydraulic shears or underwater ultrathermic cutting) and possible impact removal of approximately 4,216 sheet piles from the structure tailwalls, cell faces (bulkhead), and closure walls. Demolition of the failed sheet pile structure will be accomplished through excavation and dredging of impounded soils (fill material), and cutting and removal of the existing sheet piles, most likely through use of a pile splitter and vibratory hammer. It is assumed that pile splitting will produce the same or similar sound levels to a vibratory hammer used without the splitter attachment. Therefore, the use of a vibratory hammer to remove sheet piles and the use of a splitter is combined into a single category ( i.e., vibratory hammer removal) and treated the same in our analysis. The first attempt to extract the sheet piles will be with direct vertical pulling or with a vibratory hammer; however, there may be complications with the sheet pile interlocks, which could become seized, and other means of pile removal may be required ( i.e., impact removal, shearing, or torching). In addition, to minimize potential impacts on marine mammals from in-water sheet pile removal, removal in the dry would be maximized as feasible. The demolition plan also includes stabilization of the face sheets through installation of temporary piles and dredging back into the cell to relieve pressure on the sheet piles and to eliminate any release of material into Cook Inlet beyond natural tidal forces. It is anticipated that 3 sets of 27 temporary piles would be required for a total of 81 installations and 81 removals (table 1). Temporary piles would be installed and removed with a vibratory hammer. Sound produced by vibratory pile installation and removal and impact pile removal may result in the take of marine mammals, by harassment only. Sound produced by all other NES1 project activities ( e.g., hydraulic shearing, ultrathermic cutting) are not expected to result in the take of marine mammals and, therefore, are not discussed further. BILLING CODE 3510-22-P EN16JA24.031 BILLING CODE 3510-22-C A detailed description of the planned NES1 project is provided in the Federal Register notice for the proposed IHA (88 FR 76576, November 6, 2023). Since that time, no changes have been made to the planned activities. Therefore, a detailed description is not provided here. Please refer to that Federal Register notice for the description of the specific activity. Dates and Duration The POA anticipates that NES1 in-water construction activities will begin on April 1, 2024 and extend through November 2024. In-water pile installation and removal associated with the NES1 project is anticipated to take place over approximately 246.5 hours on 110 nonconsecutive days between these dates. While the exact sequence of demolition and construction is uncertain, an estimated schedule of sheet pile removal and temporary stability template pile installation and removal is shown in table 1. A detailed description of the timing and sequencing of the NES1 project is provided in the Federal Register notice for the proposed IHA (88 FR 76576, November 6, 2023). Since that time, no changes have been made to the dates or duration. Therefore, a detailed description is not provided here. Please refer to that Federal Register notice for more information regarding the dates and duration of the NES1 project. Specific Geographic Region The Municipality of Anchorage is located in the lower reaches of Knik Arm of upper Cook Inlet (see figure 2-1 in the POA's application). The POA sits on the industrial waterfront of Anchorage, just south of Cairn Point and north of Ship Creek (lat. 61°15′ N, long. 149°52′ W; Seward Meridian). Knik Arm and Turnagain Arm are the two branches of upper Cook Inlet, and Anchorage is located where the two arms join. The POA's boundaries currently occupy an area of approximately 0.52 km 2 . A detailed description of the specific geographic region of the NES1 project is provided in the Federal Register notice for the proposed IHA (88 FR 76576, November 6, 2023). Since that time, no changes have been made to the specific geographic region. Therefore, a detailed description is not provided here. Please refer to that Federal Register notice for more information regarding the specific geographic region of the NES1 project. Comments and Responses A notice of NMFS' proposal to issue an IHA to the POA was published in the Federal Register on November 6, 2023 (88 FR 76576). That notice described, in detail, the POA's activity, the marine mammal species that may be affected by the activity, and the anticipated effects on marine mammals. In that notice, we requested public input on the request for authorization described therein, our analyses, the proposed authorization, and any other aspect of the notice of proposed IHA, and requested that interested persons submit relevant information, suggestions, and comments. During the 30-day public comment period, NMFS received comments from the Center for Biological Diversity (CBD) and Eklutna, Inc. NMFS also received a letter from United States Geological Survey stating that they had no comment. All relevant, substantive comments, and NMFS' responses, are provided below. The comments and recommendations are available online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities. Please see the comment submissions for full details regarding the recommendations and supporting rationale. Comment 1: The CBD opposed NMFS' issuance of an IHA for construction and associated activities related to the NES1 project, stating that the proposed actions would further imperil the already critically endangered Cook Inlet beluga whale (CIBW) and that “most of the proposed activities should not be authorized until and unless [NMFS] can ensure that take will not impede the survival and recovery of the [CIBW] population.” Response: NMFS shares CBD's concern regarding the impacts of human activities on CIBWs and is committed to supporting the conservation and recovery of the species. Under section 101(a)(5)(D) of the MMPA, NMFS considers the at risk status of CIBWs (and other species) in both the negligible impact analysis and through our consideration of impact minimization measures that support the least practicable adverse impact on those species. For example, the IHA for the NES1 project includes a requirement to implement shutdown zones for CIBWs that encompass the estimated Level B harassment zones. However, section 101(a)(5)(D) also mandates that NMFS “shall issue” an IHA if we are able to make the necessary findings for any specified activity for which incidental take is requested. In accordance with our implementing regulations at 50 CFR 216.104(c), we use the best available scientific evidence to determine whether the taking by the specified activity within the specified geographic region will have a negligible impact on the species or stock and will not have an unmitigable adverse impact on the availability of such species or stock for subsistence uses. Based on the best scientific evidence available, NMFS determined that the take incidental to POA's NES1 project would have no more than a negligible impact on the affected species and stocks, including CIBW, and no unmitigable adverse impact on the availability of marine mammals for subsistence uses. Moreover, NMFS has required through the IHA implementation of mitigation and monitoring measures that balances the safety needs of this demolition project with reducing potential impacts to CIBWs and other marine mammals to the lowest level practicable, thereby providing the means of effecting the least practicable adverse impact on the affected species and stocks of marine mammals. Further, as described in the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023), data from several years of scientific monitoring at the POA during previous work involving pile driving (occurring April through November) demonstrate there is no significant difference in beluga whale sightings during and in absence of pile driving (Kendell and Cornick, 2016). While we do anticipate some behavioral modifications to occur, these will likely be limited to increased travel speeds, reduced vocalizations, and potentially traveling in more cohesive groups (Kendell and Cornick, 2016). However, we anticipate behavior will return to normal after the whales move past the POA ( e.g., when they reach productive foraging grounds north of the POA) as these areas would not be ensonified by pile driving noise. There is no evidence CIBWs have abandoned foraging in Knik Arm due to pile driving noise or that exposure to pile driving noise has resulted in more than a negligible impact to the CIBW population ( e.g., 61N Environmental, 2021, 2022a, 2022b, 2022c; Easley-Appleyard and Leonard, 2022). In light of the mitigation and monitoring measures and scientific data to date, we anticipate the impacts of any Level B harassment to CIBWs will be limited to short-term, mild to moderate behavioral changes and will not affect the fitness of any individuals. Therefore, NMFS' negligible impact determination is well supported and the authorized take for the NES1 project is neither reasonably expected nor likely to adversely affect the stock through effects on annual rates of recruitment or survival and thus, will not contribute to or exacerbate the stock's decline. Additionally, the NMFS Alaska Regional Office issued a Biological Opinion (BiOp) on December 15, 2023, under section 7 of the Endangered Species Act (ESA), on the issuance of an IHA to the POA under section 101(a)(5)(D) of the MMPA by the NMFS Office of Protected Resources (OPR) that determined that the issuance of the IHA is not likely to jeopardize the continued existence of CIBWs. CBD cited a letter from the Marine Mammal Commission (MMC) submitted to NMFS in response to the issuance of an IHA for the POA's Petroleum and Cement Terminal (PCT) project (MMC, 2020) that specifically recommended for POA construction activities, that the Service “defer issuance of the final incidental harassment authorizations to [the POA] or any other applicant proposing to conduct sound-producing activities in Cook Inlet until [it] has a reasonable basis for determining that authorizing any additional incidental harassment takes of Cook Inlet beluga whales would not contribute to or exacerbate the stock's decline.” NMFS responded to this recommendation in the Federal Register notice of the final IHA for the PCT project ( e.g., 85 FR 19294, April 1, 2020) and we incorporate that response by reference. In summary, that notice describes how there is no evidence that exposure to pile driving noise in Knik Arm has resulted in more than a negligible impact to the CIBW population. Therefore, NMFS negligible impact determination was well supported and the authorized take for the PCT project was neither reasonably expected nor likely to adversely affect the stock through effects on annual rates of recruitment or survival. Thus NMFS had a reasonable basis for determining that authorizing take incidental to the PCT project would not contribute to or exacerbate the stock's decline. Since the publication of this notice, no new information has become available that would suggest that determination was incorrect. Similarly, NMFS' independent evaluation of the best scientific evidence in this case supports our negligible impact determination and our finding that the authorized take for the NES1 project is neither reasonably expected nor likely to adversely affect the stock through effects on annual rates of recruitment or survival. Thus, NMFS has a reasonable basis for determining that authorizing take incidental to the NES1 project would not contribute to or exacerbate the stock's decline. NMFS did not receive any recommendations from the MMC regarding the proposed IHA for the NES1 project. Finally, we also note CBD's suggestion that this IHA authorizes the subject construction activities. We note that NMFS does not have authority under the MMPA or other statute to authorize the specified activity. NMFS' authority pertains only to the authorization of marine mammal take incidental to that activity and to the prescription of appropriate mitigation, monitoring, and reporting requirements. Comment 2: The CBD expressed concern regarding uncertainty in the trends of the CIBW population status. They stated that “changes in survey methods bring into question the approach of determining any trend in population status.” They cited scientific studies that confirm a negative trend in the population status of CIBWs. Response: CBD is incorrect in that survey methods for detecting trends in CIBW population have changed; the survey field methods are essentially unchanged since 2004 (Paul Wade, personal communication, December 11, 2023). The analysis methods used to detect trends in the CIBW population have been updated and implemented in recent studies examining the CIBW population, notably Sheldon and Wade (2019) and Goetz et al. (2023). Results of recent studies, including those cited by CBD, provide evidence that the CIBW population increased between 2004 and 2010, declined after 2010, and increased again from 2016 to 2022 (Jacobsen et al., 2020; Shelden and Wade, 2019; Warlick et al., 2023; Goetz et al., 2023). While there is some uncertainty around CIBW population trend analyses, the results of these four studies are consistent in showing general trends. Thus, while the CBD were correct that some studies confirm a negative trend in beluga whale abundance, recent studies, which NMFS considers the best scientific information available, suggest this trend may now be increasing. Additional data in the coming years will help to inform whether the recent positive trend in the CIBW population will continue. Comment 3: The CBD states that NMFS must conduct a comprehensive analysis of all CIBW take and asserts that NMFS should place an overall cap on authorizations for CIBW incidental take. They state that the various construction, vessel traffic, oil and gas, and other activities are cumulatively threatening the conservation and recovery of CIBWs. CBD also provides examples for the number of takes authorized by NMFS for various time periods, citing Migura and Bollini (2021) and recent authorizations to the POA. Response: We note first that the Migura and Bollini (2021) paper cited by CBD seems to have led to a misunderstanding of the takes authorized or permitted by NMFS. In summary, CBD asserts that NMFS authorized nearly 120,000 takes of CIBWs from 2017 to 2025 and that in 2020 alone, NMFS authorized the equivalent of 50 percent of the entire CIBW population to be “incidentally” harassed by industrial projects in the Inlet, such as oil and gas development and pile driving activities. The vast majority of the asserted ~120,000 total takes (99 percent), including all of the very small amount of take by Level A harassment, were authorized under directed research or enhancement permits, which directly support research or actions identified in the Recovery Plan to address CIBW recovery goals. Further, the vast majority (~99 percent) of the total permitted research or enhancement take numbers cited by CBD are low-level MMPA Level B harassment from remote or non-invasive procedures that are considered not likely to adversely affect listed species pursuant to the ESA ( i.e., no associated take under the ESA is either expected to occur or exempted for those specific activities). Regarding the comprehensive evaluation and minimization of permitted takes, we reference the analysis that has already been completed through NMFS' 2019 Biological and Conference Opinion on the Proposed Implementation of a Program for the Issuance of Permits for Research and Enhancement Activities on Cetaceans in the Arctic, Atlantic, Indian, Pacific, and Southern Oceans (NMFS, 2019), which determined that the research and enhancement takes permitted by the program would not jeopardize the existence of any of the affected species. As part of our programmatic framework for permitting directed take of ESA species, the Permits and Conservation Division will continue to closely evaluate the number and manner of CIBW takes requested by each applicant, how the proposed research ties to recovery plan goals, and the collective number of authorized and requested takes to consider the potential cumulative impact of the activities to the population. Each directed take annual report is reviewed to understand how authorized takes were actually used and to closely monitor the impacts that permitted research methods are having on the target animals. Regarding the incidental takes authorized for 2020, those takes represent instances of exposure above the Level B harassment threshold that could occur within a day. In other words, if those approximately 130 takes were assumed to be 130 separate individual whales, it would mean that those individual whales were each behaviorally disturbed on one day in that year. The more likely scenario is that some of those 130 exposures were takes of the same whale on a few different days, and in fact a lesser number of individuals were taken, but still on only a few days within a year. In all cases, the necessary findings under MMPA and ESA were made prior to the authorization of the take. Neither the MMPA nor NMFS' codified implementing regulations call for consideration of the take resulting from other activities in the negligible impact analysis. The preamble for NMFS' implementing regulations (54 FR 40338, September 29, 1989) states, in response to comments, that the impacts from other past and ongoing anthropogenic activities are to be incorporated into the negligible impact analysis via their impacts on the baseline. Consistent with that direction, NMFS has factored into its negligible impact analysis the impacts of other past and ongoing anthropogenic activities via their impacts on the baseline ( e.g., as reflected in the density/distribution and status of the species, population size and growth rate, and other relevant stressors (such as incidental mortality in commercial fisheries, Unusual Mortality Events (UMEs), and subsistence hunting); see the Negligible Impact Analyses and Determinations section of this notice of issuance). The 1989 final rule for the MMPA implementing regulations also addressed public comments regarding cumulative effects from future, unrelated activities. There, NMFS stated that such effects are not considered in making findings under section 101(a)(5) concerning negligible impact. In this case, this ITA as well as other ITAs currently in effect or proposed within the specified geographic region, are appropriately considered an unrelated activity relative to the others. The ITAs are unrelated in the sense that they are discrete actions under section 101(a)(5)(D) issued to discrete applicants. Section 101(a)(5)(D) of the MMPA requires NMFS to make a determination that the take incidental to a “specified activity” will have a negligible impact on the affected species or stocks of marine mammals and will not have an unmitigable adverse impact on the availability of such species or stocks for taking for subsistence uses. NMFS' implementing regulations require applicants to include in their request a detailed description of the specified activity or class of activities that can be expected to result in incidental taking of marine mammals (see 50 CFR 216.104(a)(1)). Thus, the “specified activity” for which incidental take coverage is being sought under section 101(a)(5)(D) is generally defined and described by the applicant. Here, the POA was the applicant for the IHA, and we are responding to the specified activity as described in that application (and making the necessary findings on that basis). Therefore, setting limits on the number and types of CIBW takes across all activities in Cook Inlet would not be an appropriate requirement of an MMPA ITA. The take estimates NMFS authorizes represent the upper limits for individuals and some instances of take may represent multiple exposures to a single individual. Separately, setting blanket take limits may not be meaningful, as the nature and intensity of impacts from a given activity can vary widely. For example, an animal exposed to noise levels just above our harassment threshold in a non-critical area may experience a small behavioral change with no biological consequence while an animal exposed to very loud noise levels (but lower than levels that would result in a permanent threshold shift (PTS)) in an area where active critical foraging occurs could result in behavioral changes that may be more likely to impact fitness. While both of these examples would be characterized as Level B harassment, the resulting impact on the population could be different. Context differences such as these are analyzed in our negligible impact analysis for each application under the MMPA. Through the response to public comments in the 1989 implementing regulations, NMFS also indicated (1) that we would consider cumulative effects that are reasonably foreseeable when preparing a National Environmental Policy Act (NEPA) analysis, and (2) that reasonably foreseeable cumulative effects would also be considered under section 7 of the ESA for ESA-listed species, as appropriate. Accordingly, NMFS has written an Environmental Assessment (EA) that addressed cumulative impacts of the NES1 project and all past, present and reasonably foreseeable future actions. Additionally, the NMFS Alaska Regional Office issued a BiOp on December 15, 2023, under section 7 of the ESA, on the issuance of an IHA to the POA under section 101(a)(5)(D) of the MMPA by the NMFS OPR that independently considered the reasonably foreseeable cumulative effects of activities on ESA-listed species. Comment 4: The CBD asserts that NMFS's negligible impact determination is arbitrary and capricious and that the specified activities would have greater than a negligible impact on CIBWs. The CBD claims that NMFS failed to substantiate its assumption that impacts are negligible because CIBWs remained in the area during similar construction activities and that NMFS underestimated the impacts of pile driving on CIBWs. They state that pile driving threatens marine mammals by potentially displacing them from key foraging habitat, causing hearing loss, masking communications, and interfering with natural behaviors. They cite several studies regarding behavioral responses of marine mammals to pile driving. Response: NMFS disagrees with the CBD's claim that NMFS failed to substantiate our assumptions that impacts to CIBWs are negligible in our determination. In the Negligible Impact Analysis and Determination section of the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023) and this notice of issuance, we describe how the take estimated and authorized for the NES1 project will have a negligible impact on all of the affected species, including CIBWs (as discussed above). We discussed how this determination is based upon the authorized number of CIBWs that might be exposed briefly during the 110 nonconsecutive days of activity, the low level of behavioral harassment that might result from an instance of take that could occur within a year, and the likelihood that the mitigation measures required further lessen the likelihood of exposures. NMFS has considered the status of CIBWs in its analysis, as well as the importance of reducing impacts from anthropogenic noise, but nonetheless, there is no evidence that brief exposure to low level noise causing Level B harassment would have a greater than negligible impact on CIBWs. NMFS' negligible impact finding considers a number of parameters including, but not limited to, the nature of the activities ( e.g., duration, sound source), effects/intensity of the taking, the context of takes, and mitigation. For CIBWs, NMFS' finding did account for data demonstrating that CIBWs are not discouraged from entering Knik Arm and traveling to critical foraging grounds to the north when pile driving activities, such as those proposed by NES1, are occurring ( e.g., 61N Environmental, 2021, 2022a, 2022b; Easley-Appleyard and Leonard, 2022), but it also relied on other data that show at most, low-level behavioral responses of CIBWs to pile driving activities. For example, during the POA's PCT and South Floating Dock (SFD) pile driving activities, CIBWs were more likely to display no reaction or to continue to move towards the POA during pile installation and removal (61N Environmental, 2021, 2022a, 2022b). In situations during which CIBWs showed a possible reaction to pile driving, individuals were observed either moving away from the pile driving activities or increasing their rate of travel (61N Environmental, 2021, 2022a, 2022b). Other behavioral responses observed in relation to pile driving activities include moving silently through the area, decreased sighting durations, and the formation of more cohesive groups (Kendall and Cornick, 2015). NMFS understands that marine mammals will have varying responses to elevated noise levels resulting from pile driving activities such as masking of communication and foraging signals, avoidance behaviors, and more. However, NMFS disagrees with CBD that we have underestimated the impacts of pile driving on beluga whales. Marine mammal data collected at the POA during pile driving activities, as described above, provides evidence that effects of pile driving on CIBWs will be limited to temporary modifications in behavior such as increased swim speeds, tighter group formations, and cessation of vocalizations, but not through the loss of foraging capabilities or abandonment of habitat. Further, while masking of CIBW signals can have a profound impact on the communication of CIBWs ( e.g., Brewer et al., 2023), the short-term duration and limited areas affected by the NES1 project make it very unlikely that the fitness of individual marine mammals would be impacted. In addition, the frequency range of pile driving activities is typically below 1 kHz (Richardson et al., 1995), which is below the peak frequencies for many CIBW communication signals (Brewer et al., 2023). Therefore, while expected impacts to CIBWs from the NES1 project are considered Level B harassment events, they are events with relatively little consequence for individuals in terms of energetic effects or foregone opportunities to engage in important foraging or social behaviors. While exposure to elevated noise levels associated with the NES1 project may result in low-level behavioral changes in CIBWs, NMFS' review of the best available scientific evidence, as summarized and cited herein, demonstrates that these responses do not rise to the level of having adverse effects on the reproduction or survival of CIBWs. CBD provides no evidence to the contrary. Therefore, NMFS has appropriately concluded that the activity will have a negligible impact on the CIBW population. Comment 5: The CBD expressed concern regarding the take estimates for CIBWs proposed by NMFS. They state that the take estimates fail to explain how pods of animals are accounted for and improperly discounts the estimated CIBW take with a 59 percent adjustment. They suggest that this supposed failure may result in a higher take than anticipated. They believe that take should be estimated without considering the demonstrated efficacy of the proposed mitigation requirements, with expected benefits of the mitigation requirements being described only separately. Response: CBD is concerned that exposure of one pod of whales to harassment by the construction could exceed the take authorized. They cite McGuire et al. (2020) which suggests CIBW groups can be between 61 and 313 whales. CBD is correct that there have been large observations of CIBW pods, and that if one very large pod appeared near the POA during pile driving activities, it could result in the POA meeting or exceeding authorized take for this species. However, such large pods are not expected to be observed near the POA based on the best scientific information available, including recent marine mammal monitoring efforts. The mean (median, standard deviation) CIBW group size observed during the 2020 through 2022 POA and NMFS marine mammal monitoring efforts in Knik Arm were 4.28 (3, 4.86) whales (61N Environmental, 2021, 2022a, 2022b; Easley-Appleyard and Leonard, 2022). Further, the 95 percentile group size of CIBWs observed during these years was 12.30 individuals. This means that of the 495 documented CIBW groups in these data sets, 95 percent consisted of fewer than 12.3 whales; 5 percent of the groups consisted of more than 12.3 whales. Lastly, the largest group observed during these efforts was 53 individuals. Therefore, NMFS believes that the 72 takes by Level B harassment authorized for CIBW during the authorized one-year period adequately accounts for the possibility of the POA taking multiple pods (or groups) of CIBWs. The CBD stated that the 59 percent adjustment is “based on one data point” from the PCT project monitoring program. This is incorrect. As described in the Estimated Take sections of the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023) and this notice of issuance, this adjustment was calculated by including data from all observations from April to November for each year of the PCT project, the same time frame over which the POA will be conducting the NES1 project. Between the two phases of the PCT project, 90 total Level B harassment takes were authorized and 53 were potentially realized ( i.e., 53 CIBWs were observed within estimated Level B harassment zones), equating to an overall percentage of 59 percent (Note that simple occurrence within the estimated harassment zone in and of itself does not demonstrate that a take has occurred). In our calculations for estimating CIBW take in the Estimated Take sections of the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023) and this notice of issuance, NMFS did preliminarily calculate take for CIBWs without the 59% adjustment ( i.e., 122 instances of take). However, we disagree with the CBD that the adjustment for mitigation requirements should be described separately and not be considered in the take estimation. This 59% adjustment is based on the effectiveness of monitoring during the PCT Phase 1 and PCT Phase 2 projects, which most accurately reflect the current POA marine mammal monitoring program, the current program's effectiveness, and CIBW occurrence in the proposed project area. It is anticipated that the POA monitoring program during the NES1 project will be similar to that of the program implemented during the PCT project. Therefore, NMFS has determined that it is appropriate to include the adjustment in our calculation of authorized take. Comment 6: The CBD assert that the root mean square (RMS) thresholds of 120-decibels (dB) referenced to 1 micropascal (re 1μPa) for continuous and 160 dB re 1μPa for impulsive or intermittent sources are insufficiently conservative to protect CIBWs. They cite Mooney et al. (2018), which suggests that wild beluga whales have highly sensitive hearing. They state that, at a minimum, NMFS should use a 120-dB threshold for all sound sources. Response: NMFS disagrees that we should apply a 120-dB threshold for Level B harassment from all sound sources based on beluga hearing sensitivity. First, we provide here some necessary background on implementation of acoustic thresholds. NMFS has historically used generalized acoustic thresholds based on received levels to predict the occurrence of behavioral disturbance rising to the level of Level B harassment, given the practical need to use a relatively simple threshold based on information that is available for most activities. Thresholds were selected largely in consideration of measured avoidance responses of mysticete whales to airgun signals and to industrial noise sources, such as drilling. The selected thresholds of 160-dB RMS sound pressure level (SPL) and 120-dB RMS SPL, respectively, have been extended for use for estimation of behavioral disturbance rising to the level of Level B harassment associated with noise exposure from sources associated with other common activities. Sound sources can be divided into broad categories based on various criteria or for various purposes. As discussed by Richardson et al. (1995), source characteristics include strength of signal amplitude, distribution of sound frequency and, importantly in context of these thresholds, variability over time. With regard to temporal properties, sounds are generally considered to be either continuous or transient ( i.e., intermittent). Continuous sounds, which are produced by the industrial noise sources (such as vibratory pile driving) for which the 120-dB behavioral threshold was selected, are simply those for which sound pressure levels remain above background sound during the observation period (ANSI, 2005). Intermittent sounds are defined as sounds with interrupted levels of low or no sound (NIOSH, 1998). Simply put, a continuous noise source produces a signal that continues over time, while an intermittent source produces signals of relatively short duration having an obvious start and end with predictable patterns of bursts of sound and silent periods ( i.e., duty cycle) (Richardson and Malme, 1993). It is this fundamental temporal distinction that is most important for categorizing sound types in terms of their potential to cause a behavioral response. For example, Gomez et al. (2016) found a significant relationship between source type and marine mammal behavioral response when sources were split into continuous ( e.g., shipping, icebreaking, drilling) versus intermittent ( e.g., sonar, seismic, explosives) types. In addition, there have been various studies noting differences in responses to intermittent and continuous sound sources for other species ( e.g., Neo et al., 2014; Radford et al., 2016; Nichols et al., 2015). Given the existing paradigm—dichotomous thresholds appropriate for generic use in evaluating the potential for behavioral disturbance rising to the level of Level B harassment resulting from exposure to continuous or intermittent sound sources—the CBD does not explain why potential harassment from an intermittent sound source ( i.e., impact pile driving) should be evaluated using a threshold developed for use with continuous sound sources. As we have stated in prior responses to this recommendation, consideration of the preceding factors leads to a conclusion that the 160-dB threshold is more appropriate for use for intermittent sources such as impact pile driving than the 120-dB threshold. Further, any dB-based threshold itself is a step-function approach ( i.e., animals exposed to received levels above the threshold are considered to be “taken” and those exposed to levels below the threshold are not); but, in reality, it is in fact intended as a sort of mid-point of likely behavioral responses (which are extremely complex depending on many factors including species, noise source, individual experience, and behavioral context). What this means is that, conceptually, the function recognizes that some animals exposed to levels below the threshold will in fact react in ways that are appropriately considered take, while others that are exposed to levels above the threshold will not. Use of a specific dB threshold allows for a simplistic quantitative estimate of take, while we can qualitatively address the variation in responses across different received levels in our discussion and analysis. Lastly, NMFS has acknowledged that the scientific evidence indicates that certain species are, in general, more acoustically sensitive than others. In particular, harbor porpoise and beaked whales are considered to be behaviorally sensitive, and it may be appropriate to consider use of lower Level B harassment thresholds for these species. Beluga whales have been observed to have sensitive hearing (<80 dB) in the frequency range of 16 to 100 kilohertz (kHz) (Mooney et al., 2018). However, noise from pile driving activities is typically below 1 kHz (Richardson et al., 1995), well outside this sensitive hearing range. Therefore, based on the best available science ( i.e., Mooney et al., 2018), sensitivity in CIBW hearing does not support the application of a 120-dB threshold for Level B harassment from all pile driving sound sources. NMFS is currently engaged in an ongoing effort to develop updated guidance regarding the effects of anthropogenic sound on marine mammal behavior, and in this effort NMFS is considering this issue for assessing Level B harassment. However, until this work is completed and new guidelines are identified (if appropriate), NMFS will continue using the historical Level B harassment thresholds (or derivations thereof) and will appropriately evaluate behavioral disturbance rising to the level of Level B harassment due to intermittent sound sources relative to the 160-dB threshold. Comment 7: CBD states that NMFS should undertake the analysis using the framework provided by Southall et al. (2023) to determine the vulnerability of marine mammals to noise disturbance. Response: Southall et al. (2023) present an analytical framework for assessing the relative risk of anthropogenic disturbances, such as those resulting from noise, on marine vertebrates. This framework is based on both species-specific `vulnerability' (which accounts for population, life history, auditory communication systems, and environmental factors) and species-specific and scenario-specific `severity' (which includes population modeling methods for acute (short-term, project specific) exposure events) and a spatial-temporal-spectral algorithm for estimating a disturbance magnitude metric from aggregate events (long-term, multiple years, and or multiple projects). For each species and exposure scenario, a vulnerability and severity risk rating are computed, which allows for the assessment of the overall risk of each scenario for each species. Lastly, in this framework a subjective consideration of confidence in the risk assessment scores is provided. The Southall et al. (2023) framework has been used to model results from the construction and operation of wind farms and seismic surveys. While the framework presented by Southall et al. (2023) is a useful tool for evaluating risk of marine mammals to exposure events, such as pile driving activities, it is intended to be used as a complementary tool to use when implementing marine policies. It is “not intended to replicate or supersede current regulatory guidelines for auditory or behavioral impact” (Southall et al., 2023). Furthermore, the framework presented by Southall et al. (2023) does not estimate defined impacts such as injury (equivalent to Level A harassment) or behavioral disturbance (equivalent to Level B harassment) that would inform take estimates. In the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023) and this notice of issuance, NMFS discusses the anticipated impacts of the NES1 project activities in the context of species status, which included an assessment of species population trends, life history traits, auditory communication systems, and environmental factors as well as estimated impacts of project activities. Thus, for this action, NMFS has determined that the application of the framework proposed by Southall et al. (2023) would not provide meaningful additive information in our assessment of take or in our negligible impact determination, and therefore, we do not apply it here. Comment 8: The CBD states that NMFS' negligible impact determination fails to adequately consider adverse impacts to CIBW critical habitat and biologically important areas (BIAs). In addition, they assert that the proposed NES1 project does not avoid or impose any specific mitigation for the year-round CIBW BIA. Response: In our analysis, NMFS considered the potential for impacts to CIBWs and their habitat in general ( see the Potential Effects of Specified Activities on Marine Mammals and their Habitat section of the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023). The CIBW Recovery Plan (NMFS, 2016b) determined that CIBWs having waters that do not restrict passage within or between critical habitat areas and having waters with in-water noise levels below levels resulting in abandonment of critical habitat were essential for the conservation of this species. While some marine mammals—largely harbor porpoise, which are generally considered as one of the most behaviorally sensitive marine mammal species—have been observed to abandon or reduce time spent in preferred habitat during periods of increased anthropogenic noise ( e.g., Wartzok et al., 2003; Carstensen et al., 2006; Dähne et al., 2012; Forney et al., 2017), CIBW presence in the project area has persisted during numerous periods of pile driving, dredging, and other construction activities at the POA. Previous monitoring data indicates that CIBWs are not abandoning critical habitat and are able to transit through the project area to primary foraging areas north of the Port. Instead, they travel more often and faster past the POA, more quietly, and in tighter groups (Kendall and Cornick, 2015; 61N Environmental, 2021, 2022a, 2022b). Moreover, marine mammal monitoring results from the POA and NMFS ( e.g., 61N Environmental, 2021, 2022a, 2022b; Easley-Appleyard and Leonard, 2022) suggest that the areas that are expected to be impacted by noise during the NES1 project are not particularly important feeding or calving areas for CIBWs. Rather CIBWs typically transit through the area adjacent to the POA to foraging areas located to the north ( e.g., Six Mile Creek, Eagle River, Eklutna River). For these reasons, NMFS expects the effects that sounds from the NES1 project will have on these essential features will be small (see NMFS, 2023a). Concerning BIAs, CBD improperly cited Ferguson et al. (2015) when referring to the CIBW BIA. This BIA was updated by Wild et al. (2023) as part of the BIA II effort, which built upon the 2015 study but used new methodology and structured expert elicitation principles to update existing BIAs, and identify and delineate new BIAs (see Harrison et al., 2023). In this new effort, Wild et al. (2023) defined a static, year-round, small and resident BIA for CIBWs whose boundary is consistent with NMFS' critical habitat designation, (including excluding the area adjacent to POA, illustrating that the area is of low value) (Wild et al., 2023). In regards to specific mitigation requirements for this year-round BIA, the proposed IHA does include a measure that requires the POA to make all practicable efforts to complete construction activities between April and July when CIBWs are typically found in lower numbers near the POA. However, due to the design of the existing sheet pile wall, the need for demolition to occur in a sequential manner to prevent structural failure, and uncertainty regarding construction progress until work is initiated, the POA cannot commit to restricting pile driving to these months. Given that the location and sequencing of the activity cannot be changed, NMFS has prescribed mitigation measures that affect the least practicable adverse impact on the stock. CBD did not provide a specific recommendation for NMFS to consider. Comment 9: The CBD stresses that NMFS should have analyzed the potential impact on feeding of preferred prey in making its negligible impact determination. Response: NMFS provided this information in the Acoustic Impacts section of the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023), and provides additional discussion in the Negligible Impact Analysis and Determination section for CIBWs of this notice. In summary, the habitat near the POA is not typically considered high quality foraging habitat for CIBWs and feeding is not a predominant behavior observed in CIBWs near the POA. Further, there is no evidence to suggest that CIBWs are restricted in transiting between preferred feeding areas during pile driving activities ( e.g., 61N Environmental, 2021, 2022a, 2022b, 2022c; Easley-Appleyard and Leonard, 2022). Lastly, any impacts to preferred prey are anticipated to be temporary, and most likely limited to fish avoiding the action area. Comment 10: The CBD postulates that NMFS' small numbers determination is flawed because the amount of take proposed to be authorized is greater than 12 percent of the CIBW population and that NMFS' definition of small numbers “conflates this criterion with the negligible impact requirement.” CBD claims the incidental harassment authorization here violates the MMPA because it does not guarantee that only small numbers of CIBWs and other marine mammals impacted by the POA's activities will be taken. Response: CBD suggests that by defining small numbers to be relative to the overall population the criterion ends up being similar to the negligible impact finding and that Congress's intent was that the MMPA protect not only populations, but individual marine mammals. We disagree that our small numbers finding is conflated with our negligible impact finding. While “small numbers” is simply a percent of the population, our negligible impact finding considers a number of parameters including, but not limited to, the nature of the activities ( e.g., duration, sound source), effects/intensity of the taking, the context of takes, and mitigation. The reference to a take limit of 12 percent for small numbers comes from a 2003 district court opinion ( Natural Resources Defense Council v. Evans, 279 F.Supp.2d 1129 (N.D. Cal. 2003)). However, given the particular administrative record and circumstances in that case, including the fact that our small numbers finding for the challenged incidental take rule was based on an invalid regulatory definition of small numbers, we view the district court's opinion regarding 12 percent as dicta. In NMFS' Final Rule for taking of marine mammals incidental to geophysical surveys in the Gulf of Mexico (86 FR 5322, January 19, 2021), NMFS fully describes its interpretation and implementation of “small numbers”. Included as part of that discussion, NMFS explains the concept of “small numbers” in recognition that there could also be quantities of individuals taken that would correspond with “medium” and “large” numbers. As such, NMFS has established that one-third of the most appropriate population abundance number—as compared with the assumed number of individuals taken—is an appropriate limit with regard to “small numbers.” This relative approach is consistent with the statement from the legislative history that “[small numbers] is not capable of being expressed in absolute numerical limits” (H.R. Rep. No. 97-228, at 19 (September 16, 1981)), and relevant case law ( Center for Biological Diversity v. Salazar, 695 F.3d 893, 907 (9th Cir. 2012) (holding that the U.S. Fish and Wildlife Service reasonably interpreted “small numbers” by analyzing take in relative or proportional terms)). As described in the Small Numbers section of the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023) and this notice of issuance, NMFS is authorizing take of less than 2 percent for eight stocks and 22 percent for one stock ( i.e., CIBWs) and based on this analysis, NMFS finds that small numbers of marine mammals will be taken relative to the population size of the affected species or stocks. Comment 11: CBD asserts that NMFS relies on visual monitoring measures that it claims are “known to be ineffective and inadequate” to protect marine mammals. Response: NMFS disagrees the mitigation and monitoring measures included in this authorization are ineffective and inadequate and CBD does not provide additional information to support their claim. The IHA requires a minimum of two Protected Species Observer (PSO) stations, and that at each station, at least two PSOs must be on watch at any given time. Further, the PSO stations must be located so that the PSOs can fully monitor the shutdown zones and call for activities to be delayed when CIBWs are entering or observed within the Level B harassment zones. The POA has a demonstrated history of successfully implementing a rigorous monitoring program during recent construction projects in Knik Arm ( i.e., PCT and SFD), and monitoring data from these projects provides evidence that their PSOs are capable of observing belugas out to 11,057-m from the NES1 project site. This distance is dependent on several factors such as visual acuity, sea state, glare, animal behavior/body type, speed of travel for vessel and animal, etc. ; but this demonstrates that it is possible for PSOs to detect and identify marine mammals to the species level several km from the source, including CIBWs. In addition, Easley-Appleyard and Leonard (2022) reported that PSOs who worked for the PCT monitoring program expressed that they were effective at detecting CIBWs from two monitoring stations despite occasional challenges related to the timing of the detection and the ability to track multiple CIBW groups. The majority of the work for this project will be the vibratory removal of sheet piles, which has an estimated Level B harassment distance of 1,954-m. The largest zones will be associated with the installation and removal of the temporary steel pipe piles, which could have estimated Level B harassment zones up to 6,861-m. These distances are well within the distances that PSOs at the POA have effectively detected CIBWs as described above. Further, there are mitigation measures preventing pile driving from occurring if visibility in any portion of the shutdown zone ( i.e., the Level B harassment zone for CIBWs) is obscured by weather or sea state. Therefore, we find the visual monitoring plan can reasonably be expected to be an effective tool at detecting marine mammals, ensuring the mitigation measures are adhered to. Comment 12: CBD suggests that construction should be restricted from August through October, and further states that NMFS “should also consider time area restrictions that would further mitigate impacts to beluga whales and other marine mammals,” though it provides no recommendations. Response: Time-area restrictions were considered for this project, in addition to the PSO requirements. We note that August through November are months with high CIBW abundance, and NMFS expects that the POA will likely have to shut down pile driving activities more frequently during that time period due to the increased presence of CIBWs in Knik Arm. NMFS is requiring the POA to complete in-water work as early in the construction season as is practicable. However, the design of the existing sheet pile wall, the safety requirements of the demolition sequencing, and the likely highly adaptive nature of the field work once construction commences do not allow NMFS to practicably restrict pile driving to any specific time periods or areas ( e.g., only allowing pile driving April through July). Furthermore, there are potential consequences of pausing or delaying the construction season, including de-rating the structural capacity of the existing docks, a shutdown of dock operations due to deteriorated conditions, or an actual collapse of one or more dock structures. The potential for collapse increases with schedule delays, due to both worsening deterioration and the higher probability of a significant seismic event occurring. Any of these scenarios could have dire consequences for the populations of Anchorage and Alaska who are served by the POA. In this context, NMFS has determined that the current mitigation and monitoring measures affect the least practicable adverse impact on marine mammal species and stocks. Comment 13: CDB states that NMFS failed to consider other mitigation measures to reduce the proposed activities' impacts to the least practicable level such as bubble curtains placement configurations, pile caps, physical barrier technologies, such as dewatered cofferdams, passive acoustic monitoring (PAM), and sound source verification (SSV) studies. Response: CBD does not provide any specific information contradicting NMFS' determinations concerning whether these measures should be included in the suite of mitigation requirements determined to provide the means of effecting the least practicable adverse impact on the affected species or stocks of marine mammals. CBD states that bubble curtains were required for previous POA pile driving activities, and recommends that one could be placed beyond the construction area for the NES1 site due to spacing and safety concerns. They also state that NMFS could consider other noise mitigation technologies such as pile caps, dewatered cofferdams, and other physical barrier mitigation. CBD is correct that NMFS has required the POA to use bubble curtains for other POA pile driving activities. During construction of the PCT, two different types of bubble curtain systems were utilized, confined bubble curtain systems and unconfined bubble curtain systems. Both bubble curtain systems were expensive to construct, maintain, and repair. It was necessary to build several versions of each model for each pile size in case of damage and so that two or more piles could be simultaneously staged and prepared for installation, which was done in an effort to save time. Both bubble curtain systems were time-consuming to deploy and retrieve, adding an average of 6 hours (confined) and 4 hours (unconfined) of deployment and retrieval time to each pile. Thus, as described in the Proposed Mitigation section of the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023), adding a requirement for a bubble curtain may hinder production of the NES1 project, which could push the in-water construction schedule further into the late summer months, which are known for higher CIBW abundance in lower Knik Arm, thus lengthening the duration of potential interactions between CIBW and in-water works. Lastly, data from prior SSV studies conducted during the PCT project ( i.e., Illingworth & Rodkin (I&R), 2021a, 2022b), yielded mixed results regarding the efficacy of bubble curtains for use with vibratory hammers (which makes up the majority of the NES1 project). Therefore, a requirement to use bubble curtains in this case (aside from the cost and safety concerns) would likely have a detrimental impact over the full scope of the project. Further, dredging associated with the NES1 project will frequently require barges and vessels to maneuver through the area between the sheet pile face and the disposal area located in the middle of Knik Arm. Additional barges to stage air compressors for a bubble curtain would add multiple anchor lines that would present a logistical challenge to the frequent vessel transit and increase the risk of a safety incident, particularly if there were to be an uncontrolled release of sediments from a structure collapse. Additional vessels, air compressors, and crew also increase the cost and potential negative impacts of the project. The POA believes this combination of logistical challenges, time requirements, and safety considerations make it impractical for the POA to use a bubble curtain for this project. NMFS has considered input from the POA, as well as other information, and concurs that use of bubble curtains is not practicable in this case. Additional information regarding practicability and efficacy concerns with using bubble curtains during the NES1 project were included in the Proposed Mitigation section of the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023) and the Mitigation section of this notice. Pile cap cushions are commonly used in conjunction with an impact hammer to reduce stress on a pile during hammer blows. Their efficacy as an underwater sound attenuation measure during pile installation remains uncertain. There are safety and logistical concerns with the use of a pile cap cushion as they have been known to combust from the friction created during impact pile driving. The NES1 project does not involve the installation of piles using an impact hammer. Pile cap cushions are not compatible with vibratory pile installation or removal, or with sheet pile installation or removal. Therefore, the inclusion of pile caps is not a feasible option for this project. Other physical barrier technologies, such as dewatered cofferdams, would substantially increase project risks, construction schedule and costs. Cofferdams are typically sheet pile structures supported by cylindrical steel piles that would require installation and removal of temporary sheet and cylindrical piles along the entire length of the NES1 face sheets, which would increase potential impacts on CIBWs and other marine species. Other physical barriers installed into Knik Arm would also need to be engineered to a level to resist the tidal forces of Knik Arm, and would likely require pile supports, increasing impacts, duration, and cost. Thus, NMFS has determined that the recommendation of applying other physical barriers to mitigate noise from construction activities is not an appropriate addition to the required suite of mitigation measures for the NES1 project. In addition, the CBD states that NMFS should require PAM for marine mammals. The use of PAM for real-time mitigation purposes has been used in Cook Inlet for some studies. These efforts have generally not resulted in successful deployment of PAM or useful detections of marine mammals to inform mitigation and monitoring during the activities due to the environmental conditions of the region. For example, a real-time PAM system implemented as part of the 2012 Apache 3D seismic survey program in lower- and mid-Cook Inlet only yielded six confirmed marine mammal detections. One of these detections was of a CIBW, however, it did not result in a shutdown procedure (Lomac-MacNair et al., 2013). Similarly, a real-time PAM program was required in the IHA for the 2015 SAExploration 3D seismic program. This program only detected 15 marine mammal detections (including 2 from CIBWs) over 310 hours. For these reasons, we have determined PAM is not likely to be sufficiently effective at detection for real-time mitigation for the POA's construction activities and, therefore, is not included in the IHA. Researchers have begun to implement more effective passive acoustic monitors for research purposes at several places in Cook Inlet ( e.g., Castellote et al., 2020). However, the framework used by those researchers is impractical, particularly for the POA's planned activity. An article on NOAA's website ( https://www.fisheries.noaa.gov/science-blog/beluga-whale-acoustic-monitoring-survey-post-3 ) illustrates the level of customization, expertise, and difficulty required to assemble a passive acoustic mooring to then deploy in the Inlet. Additionally, these instruments are stationary, which means to effectively use these monitors as a means of avoiding harassment of marine mammals during the POA's, the POA would need to build and successfully deploy dozens (or more) of stationary monitors along a route of travel that is subject to change depending upon weather or other environmental and shipping restrictions. Additionally, the data stored on these types of moorings is not accessible until they are retrieved by the researcher who deployed them. In the future, if an established network of passive acoustic monitors with shared access to the data is available, this could be a useful tool for implementing mitigation measures, but is currently not practicable. NMFS looks forward to advances in technology that could make real-time PAM a practicable mitigation measure in these areas in the future. Lastly, CBD recommends that NMFS should require that in-situ SSV studies be conducted to ensure that the Level A and Level B harassment zones are sufficient. Lessons learned from prior SSV studies carried out at the POA ( e.g., I&R, 2021a, 2022b) indicate that Knik Arm is a very challenging environment to collect high quality acoustic data usable by NMFS, the POA, and others due to the presence of strong tidal currents, which can create substantial flow noise in recordings, and prevalent anthropogenic noise, which can mask acoustic signals of interest. Specifically during the NES1 project, multiple barges, tugs, and other support vessels, which can obscure signals of interest, will be within the action area at all times during the project. Further, active dredging and removal of above-water soils, and vessels with generators running will be present at all times. While both the POA and NMFS believe sound source data would be valuable, this measure is not practicable given the known challenges of the area. Comment 14: CBD asserts that NMFS should require larger exclusion zones. Response: CBD did not provide any additional information for NMFS to consider to support this recommendation. The exclusion zones proposed in the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023) (referred to as shutdown zones) are equivalent to the estimated Level B harassment zone for CIBWs. This is consistent with shutdown zones required in other recent ITAs issued to the POA for construction activities at the Port including the PCT (85 FR 19284, April 6, 2020) and SFD (86 FR 50057, September 7, 2021) projects, which resulted in the number of CIBWs occurring within estimated harassment zones being 59 percent and 7 percent of the authorized take for each project, respectively. Therefore, NMFS disagrees that the final IHA should include larger exclusion zones and requires the exclusion zones proposed in the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023) in the final IHA. Comment 15: The CBD asserts that a 1-year renewal should require new permitting and programmatic analysis of impacts. Response: NMFS disagrees with this assertion. NMFS' IHA Renewal process meets all statutory requirements. All IHAs issued, whether an initial IHA or a Renewal IHA, are valid for a period of not more than 1-year. Renewal IHAs are limited to another year of identical or nearly identical activities in the same location or the same activities that were not completed within the 1-year period of the initial IHA. Should a Renewal request be made, additional documentation would be required from the POA that NMFS would make publicly available and would use to verify that the activities are identical to those in the initial IHA, are nearly identical such that the changes would have either no effect on impacts to marine mammals or decrease those impacts, or are a subset of activities already analyzed and authorized but not completed under the initial IHA. NMFS would also confirm, among other things, that the activities would occur in the same location; involve the same species and stocks; provide for continuation of the same mitigation, monitoring, and reporting requirements; and that no new information had been received that would alter the prior analysis. If new information has been received that would alter the prior analysis, that information would be analyzed in the notice of the proposed Renewal IHA. A Renewal request would also contain a preliminary monitoring report, specifically to verify that effects from the activities do not indicate impacts of a scale or nature not previously analyzed. Any Renewal request is subject to an additional 15-day public comment period that provides the public an opportunity to review these few documents, provide any additional pertinent information and comment on whether they think the criteria for a Renewal have been met. Between the initial 30-day comment period on these same activities and the additional 15 days, the total comment period for a Renewal is 45 days. In addition to the IHA Renewal process being consistent with all requirements under section 101(a)(5)(D), it is also consistent with Congress' intent for issuance of IHAs to the extent reflected in statements in the legislative history of the MMPA. Through the provision for Renewals in the regulations, description of the process and express invitation to comment on specific potential Renewals in the Request for Public Comments section of each proposed IHA, the description of the process on NMFS' website, further elaboration on the process through responses to comments such as these, posting of substantive documents on the agency's website, and provision of 30 or 45 days for public review and comment on all proposed initial IHAs and Renewals respectively, NMFS has ensured that the public “is invited and encouraged to participate fully in the agency decision-making process.” Regarding a programmatic analysis, we refer to our response to Comment 3. Comment 16: CBD asserts that the proposed activities will have an unmitigable adverse impact on subsistence uses. CBD states that the proposed activities may have an adverse impact on the availability of beluga whales, harbor seals, and Steller sea lions for Native Alaskan subsistence harvest. They also state that the IHA should require consultation with Native Alaskan communities to ensure adequate mitigation for subsistence harvest for harbor seals and Steller sea lions. Response: The POA sent letters to and conducted follow-up calls with the Kenaitze, Tyonek, Knik, Eklutna, Ninilchik, Salamatof, and Chickaloon Tribes informing them of the proposed project ( i.e., timing, location, and features), the availability of the notice of proposed IHA for public comment, and inquiring about any marine mammal subsistence concerns they have. The POA also explained the measures that have been taken or will be taken to minimize any adverse effects of NES1 on the availability of marine mammals for subsistence uses. No Tribes or affected subsistence communities/users expressed concern over subsistence use during the 30-day public comment period for the proposed IHA. One letter was received from Eklutna Inc. requesting that Alaska Native residents with traditional knowledge about marine mammals and the local marine environment be involved in the monitoring and support roles related to the project ( i.e., as PSOs) (see Comment 22 Response), but it did not suggest concerns regarding unmitigable adverse impact on subsistence uses. The POA adequately communicated with representative Alaska Native subsistence users and Tribal members to ensure any concerns they had regarding marine mammal subsistence uses would be addressed, hence fulfilling any requirements provided by the MMPA. Overall, there is little subsistence use of marine mammals near the project area. There has been no subsistence harvest of CIBWs since 2005 (NMFS, 2022d) and subsistence harvest of other marine mammals in upper Cook Inlet is limited to harbor seals. Steller sea lions are rare in upper Cook Inlet; therefore, subsistence use of this species is not common. Residents of the Native Village of Tyonek are the primary subsistence users in the upper Cook Inlet area, however no NES1 activities will take place in or near Tyonek's identified traditional subsistence hunting areas. Additionally, the harvest of marine mammals in upper Cook Inlet is historically a small portion of the total subsistence harvest, and the number of marine mammals harvested in upper Cook Inlet is expected to remain low. The potential impacts from harassment on stocks that are harvested in Cook Inlet would be limited to minor behavioral changes ( e.g., increased swim speeds, changes in dive time, temporary avoidance near the POA) within the vicinity of the POA or slight PTS. NMFS has found that the taking of marine mammals incidental to the NES1 project would have a negligible impact on the population, meaning we do not anticipate there to be adverse impacts on the annual rates of recruitment or survival. Therefore, the taking would not impede recovery of CIBW for potential future subsistence use. The full explanation and support for this finding is described further in the Unmitigable Adverse Impact Determination section of this notice. NMFS has required rigorous mitigation and monitoring measures in the IHA to reduce impacts to CIBWs, Steller sea lions, and harbor seals including shutdown measures at the Level B harassment zone for CIBWs and Level A harassment zone for harbor seals and Steller sea lions if pile driving is occurring and an animal enters the zone. These measures are expected to reduce both the scope and severity of potential harassment takes by reducing the potential for exposure above harassment thresholds. In addition to the mitigation measures, the POA will monitor from elevated platforms at a minimum of two locations dispersed throughout lower Knik Arm. All stations will have at least two NMFS-approved observers on-watch at any given time. Therefore, marine mammal detection effectiveness is expected to be high. In accordance with our implementing regulations at 50 CFR 216.104(c), we use the best available scientific evidence to determine whether the taking by the specified activity within the specified geographic region will have a negligible impact on the species or stock and will not have an unmitigable adverse impact on the availability of such species or stock for subsistence uses. Based on the scientific evidence available, NMFS determined that the impacts of the authorized take incidental to pile driving would result in a negligible impact and no unmitigable adverse impact on availability of marine mammals for subsistence uses. Comment 17: CBD states that NMFS must prepare a programmatic environmental impact statement (EIS) for its CIBW take authorizations. They state that at a minimum, NMFS should analyze the PAMP in a single NEPA review that considers all cumulative, indirect, and direct environmental effects. Response: For clarity, NMFS' authorization does not “approve activities”; that permitting responsibility lies with the United States Army Corps of Engineers (USACE). Rather, NMFS authorizes unintentional take of marine mammals incidental to specified activities. Therefore, under NEPA, NMFS must evaluate the impacts of our issuance of the ITA to the POA for the NES1 activities. NMFS originally declared its intent to prepare an EIS for oil and gas activities in Cook Inlet, Alaska (79 FR 61616, October 14, 2014). However, in a 2017 Federal Register notice (82 FR 41939, September 5, 2017), NMFS indicated that due to a reduced number of ITA requests in the region, combined with funding constraints at that time, we were postponing any potential preparation of an EIS for oil and gas activities in Cook Inlet. As stated in the 2017 Federal Register notice, should the number of ITA requests, or anticipated requests, noticeably increase, NMFS will re-evaluate whether preparation of an EIS is necessary. Currently, the number of ITA requests for activities that may affect marine mammals in Cook Inlet is at such a level that preparation of an EIS is not yet necessary. Nonetheless, under NEPA, NMFS is required to consider cumulative effects of other potential activities in the same geographic area, and these are discussed in greater detail in the Final EA prepared for this issuance of an IHA to the POA for the NES1 project, which supports our finding that NMFS' issuance of the POA IHA will not have a significant impact on the human environment. CBD assert that NMFS should analyze the PAMP in a single NEPA review and comment that “[NMFS] has already segmented analysis of the [PCT] and [SFD] and, here, the NES1 construction”. NMFS has appropriately analyzed and captured all past, present and reasonably foreseeable future actions under NEPA. This includes the projects associated with the PAMP, which each have independent utility and require separate authorizations and NEPA analyses. The EAs for each PAMP activity appropriately analyze the cumulative, indirect, and direct environmental effects of each specified action. They include an evaluation of each action's affected area, the scale and geographic extent of each action, and the degree of cumulative effects on resources (including the duration of impact, and whether the impacts were adverse and/or beneficial and their magnitude) under NEPA. CBD is correct that Federal agencies generally prepare an EIS for a major Federal action significantly affecting the quality of the human environment. While CBD acknowledges that significance is determined by considering the potential affected environment and the degree of the action (40 CFR 1501.3(b)), CBD argues that if this factor is met, then the agency must prepare an EIS. CBD further argues that, “the impacts on an endangered species like the environmentally and culturally significant Cook Inlet beluga and its designated critical habitat is sufficient to trigger a full EIS.” NMFS disagrees. NMFS can prepare an EA so long as the record supports the conclusion that potential impacts are not “significant” per 40 CFR 1501.3(b) for the purposes of NEPA. Based on the information presented in the application and NMFS' Policy and Procedures for Compliance with the NEPA and Related Authorities (Companion Manual (CM) for NOAA Administrative Order (NAO) 216-6A) (NOAA 2017), sections 3 and 7, NMFS' determination to prepare an EA is appropriate and in compliance with NEPA and 40 CFR 1501.3. NMFS appropriately signed a Finding of No Significant Impact (FONSI) for the issuance of the IHA for incidental take associated with the POA's NES1 project in support of this determination. The FONSI concluded that NMFS' proposed action, the issuance of an IHA to the POA, will not meaningfully contribute to significant impacts to specific resources, given the limited scope of NMFS' action and required mitigation measures. Accordingly, preparation of an EIS for this action is not necessary. Comment 18: CBD believes the draft EA for the NES1 project fails to comply with the requirements of NEPA. They stipulate that the draft EA fails to consider a reasonable range of alternatives and lacks a meaningful environmental and cumulative impacts analysis. Response: In accordance with the NEPA and the Council on Environmental Quality (CEQ) Regulations, NMFS is required to consider a reasonable range of alternatives to a Proposed Action, as well as a No Action Alternative. Reasonable alternatives are viable options for meeting the purpose and need for the proposed action. The evaluation of alternatives under NEPA assists NMFS with understanding, and as appropriate, minimizing impacts through an assessment of alternative ways to achieve the purpose and need for our Proposed Action. Reasonable alternatives are carried forward for detailed evaluation under NEPA while alternatives considered but determined not to meet the purpose and need are not carried forward. For the purposes of this EA, an alternative will only meet the purpose and need if it satisfies the requirements of section 101(a)(5)(D) of the MMPA. In accordance with NOAA's implementing procedures, the CM for NAO 216-6A, Section 6.B.i, NMFS is defining the No Action alternative as not authorizing the requested incidental take of marine mammals under Section 101(a)(5)(D) of the MMPA. This is consistent with our statutory obligation under the MMPA to either: (1) Deny the requested authorization; or (2) grant the requested authorization and prescribe mitigation, monitoring, and reporting requirements. The Preferred Alternative ( i.e., issuance of the IHA) includes mandatory mitigation, monitoring, and reporting requirements for POA to achieve the MMPA standard of effecting the least practicable adverse impact on each species or stock of marine mammal and their habitat, paying particular attention to rookeries, mating grounds, and other areas of similar significance. Since NMFS is required to prescribe mitigation to effect the least practicable adverse impact on marine mammals, mitigation that reduces impacts on marine mammals is inherently included in Alternative 2 (the proposed action) and is included as part of the analysis of alternative(s) in the Environmental Consequences chapter in the EA. NMFS described both the No Action Alternative and Preferred Alternative in the EA. We have also included an “Alternatives Considered but Eliminated from Further Consideration” section in the final EA that considered whether other alternatives could meet the purpose and need while supporting this applicant's proposal to demolish the NES. There is no requirement under NEPA to consider more than two alternatives, or to consider alternatives that are substantially similar to other alternatives or which have substantially similar consequences. NMFS' range of alternatives is based on the proposed action and the purpose and need, which are linked to NMFS' authorities under the MMPA. For the purposes of analysis under NEPA in the EA, an alternative will only meet the purpose and need if it satisfies the requirements under section 101(a)(5)(D) of the MMPA. Therefore, NMFS determined that, based on our authorities and criteria under the MMPA, which included criteria regarding mitigation measures, appropriate considerations were applied to identify which alternatives to carry forward for analysis. CBD comments that the environmental and cumulative impacts section of the EA is not sufficient. CBD asserts that NMFS does not evaluate what the level of take will have on individual whales or the population, and fails to take into account any impact to CIBW pods. In addition, they state that NMFS does not include the most recent available information regarding the impacts of noise on marine mammals, and new information about CIBWs. In the draft EA, NMFS described both the general effects to marine mammals from exposure to noise ( e.g., pile driving) and scientific literature identifying responses of CIBWs to pile driving at the POA in Chapter 4 of the EA. This includes, as described in the Federal Register notice of proposed IHA (88 FR 76576, November 6, 2023) and in our response to Comment 1, data from several years of recent scientific monitoring at the POA during previous work involving pile driving ( e.g., Kendall and Cornick, 2016; 61N Environmental, 2021, 2022a, 2022b, 2022c; Easley-Appleyard and Leonard, 2022). In Chapter 3 of the EA we also describe anticipated impacts on marine mammal habitat and their prey. We believe these descriptions are sufficient with regard to the requirements of NEPA and the CEQ regulations. NMFS disagrees that we did not include the most recent available information about noise on marine mammals or new information about CIBWs. As described above, the EA includes an analysis of CIBW observations directly in relation to in-water construction, including pile driving activities from 2020 through 2021 that took place at the POA (61N Environmental, 2021, 2022a, 2022b, 2022c; Easley-Appleyard and Leonard, 2022). Chapter 4 of the EA also includes an assessment on the impacts on marine mammals to noise that includes recent information on permanent and temporary threshold shifts, avoidance or abandonment behaviors, changes in vocalizations, and the masking of communication and foraging signals. The impacts of the NES1 project on marine mammals, including CIBWs, are expected to represent short-term, localized, negligible, adverse, direct impacts. For CIBWs, NMFS anticipates these impacts will manifest as whales moving more quickly and silently through the area, in more cohesive groups, but not by habitat abandonment or ceasing traveling through Knik Arm. CBD also states that the draft EA fails to evaluate the cumulative impacts of other proposed projects and ongoing activities in Cook Inlet. In Chapter 4 of the draft EA, NMFS evaluated the cumulative impacts of the past, present, and reasonably foreseeable future actions in the action area, including projects associated with PAMP and the Alaska LNG project, which the CBD mentioned should be included, and research activities. These instances do not change NMFS' overall determination regarding the cumulative impacts of the NES1 project on marine mammals or marine mammal habitat. As stated in the draft EA, while consideration of activities in sum suggests an increase in industrialization of Cook Inlet, many of the past, present, and reasonably foreseeable future actions are spatially and temporally limited and do not permanently reduce or degrade the habitat available to marine mammals or their prey species. While the NES1 project would add an incremental contribution to the combined environmental impacts of other past, present, and reasonably foreseeable future actions; those direct and indirect adverse impacts are expected to be mainly short-term, localized, and minor, as described in the draft EA. None of the harassment authorized by NMFS in other ITAs would overlap in time or space with impacts from the NES1 Project. The CBD postulates that NMFS' consideration of climate change is inadequate. However, CBD improperly states that the proposed project is for cement and petroleum. That is incorrect as the proposed project is for the demolition of portions of the failed NES sheet pile structure and reconfiguration and realignment of the shoreline within the North Extension. NMFS considers climate change in its EA. However, as mentioned above NMFS does not authorize any of the POA's activities but rather take of marine mammals incidental to the POA's activities. While changes in environmental conditions due to climate change could result in prey distribution changes or loss for beluga whales or other marine mammals, the NES1 project is planned to occur during a 1-year period, during which time the impacts of climate change on marine mammals are likely to remain at baseline levels. Comment 19: CBD states that NMFS must comply with the ESA but asserts that NMFS should not issue take authorization under the ESA because such taking would jeopardize the continued existence of CIBWs. Response: In the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023), NMFS indicated that we requested section 7 consultation under the ESA. CBD indicates they believe the proposed taking would jeopardize the recovery and survival of CIBWs but did not further explain how they reached this conclusion. NMFS has fully complied with the ESA. NMFS Alaska Region issued a BiOp on December 15, 2023 concluding that issuance of take, by harassment, of CIBW, humpback whales (Mexico Distinct Population Segment (DPS) and Western DPS), and Steller sea lions would not jeopardize the continued existence of those stocks and the takings would not adversely modify critical habitat. The full analysis supporting these conclusions can be found in the BiOp (NMFS, 2023a). Comment 20: In their letter, CBD stated they did not believe NMFS should authorize take of CIBWs and other marine mammals but, if NMFS did take action to do so, we must impose stringent mitigation measures to ensure the least practicable adverse impact on protected species. Response: The proposed IHA included a suite of mitigation measures, which have been carried forward into the final IHA, which NMFS determined to effect the least practicable adverse impact on marine mammals, in accordance with the MMPA (see the Mitigation section). Comment 21: A commenter from Eklutna, Inc. representing the indigenous Dena'ina people of the Anchorage, Alaska area requested that Dena'ina individuals from the local area be trained and employed as NMFS-approved PSOs. They stated that the Dena'ina people possess a deep-seated knowledge and understanding of the local marine ecosystem, particularly concerning the marine mammals that NMFS aims to protect through its monitoring efforts. Given the significance of these species to their way of life and the potential impacts of the NES1 project, the commenter proposed that members of their community be actively involved in the monitoring and support roles related to the project. They stressed that this initiative would not only ensure effective monitoring of marine mammals, but also foster a sense of ownership and participation among the indigenous community in the conservation efforts. Response: NMFS agrees that Alaska Native residents with traditional knowledge about marine mammals and the local marine environment hold valuable knowledge and skills that are critical to the effectiveness of a PSO. In the final IHA, NMFS requires at least one PSO to have at least 1-year of prior experience performing the duties of a PSO during construction activity pursuant to a NMFS-issued ITA or Letter of Concurrence. Other PSOs may substitute other relevant experience, education (degree in biological science or related field), or training for prior experience performing the duties of a PSO during construction activity pursuant to a NMFS-issued ITA. For this project, in consideration of valuable traditional ecological knowledge that many community members hold, PSOs may also substitute relevant Alaska native traditional knowledge for experience. Regarding hiring preference for regional residents with traditional ecological knowledge, NMFS cannot require an IHA-holder to employ certain individuals, though it does require that an applicant request NMFS approval for all PSOs so that NMFS can confirm that they meet the requirements outlined in the IHA. NMFS has passed this recommendation on to the POA for its consideration and has suggested that the POA send letters to the Kenaitze, Tyonek, Knik, Eklutna, Ninilchik, Salamatof, and Chickaloon Tribes informing them of the hiring process when known. Changes From the Proposed IHA to Final IHA As a result of the public comments received from CBD and Eklutna, Inc. (and summarized above), provisions were added to the final IHA and this Federal Register notice of issuance that incorporates additional discussion regarding impacts to CIBW preferred prey, and our clarification of requirements related to PSO qualifications ( i.e., making clear that relevant Alaska native traditional knowledge can be considered as a substitute for relevant experience when considering prospective PSOs for the NES1 project). Since the Federal Register notice of the proposed IHA was published (88 FR 76576, November 6, 2023), NMFS became aware of an error in the calculation of the RMS SPLs that were used as proxies for unattenuated vibratory pile removal of steel pipe piles for this project. NMFS has recalculated these levels and has revised the Estimated Take section accordingly. Specifically, the RMS SPL proxy for the vibratory removal of 24-inch (61-cm) piles changed from 168-dB to 169-dB. The RMS SPL for the vibratory removal of 36-inch (91-cm) piles did not change ( i.e., it remains 159-dB RMS). As a result of the change to the 24-inch (61-cm) RMS SPL, the Level B harassment zone for this activity increased from 5,967-m to 6,861-m, and the Level A harassment zones for low-frequency cetaceans, mid-frequency cetaceans, high-frequency cetaceans, and phocid pinniped increased slightly ( i.e., between 1-m to 7-m increases). Given the shutdown zone for CIBWs is equivalent to the Level B harassment zone (see the Mitigation section of this Federal Register notice of issuance), the shutdown zone for this activity has increased from 6,000-m to 6,900-m (6,861-m rounded up) for this species. The shutdown zone for low-frequency cetaceans also increased from 40-m to 50-m due to this change. In the proposed IHA, NMFS proposed to require the POA to submit interim weekly and monthly monitoring reports (that include raw electronic data sheets) during the NES1 construction season. Since the Federal Register notice of the proposed IHA published (88 FR 76576, November 6, 2023), the POA has expressed concern that the inclusion of raw electronic data sheets with weekly and monthly reports will not be feasible for their monitoring program. In addition, the raw data will need to be reviewed and corrected for any errors. Rather, the POA has agreed to submit the final electronic data sheets with the final draft summary report. NMFS has accepted this request and has revised the final IHA to indicate that the final electronic data sheets must be submitted with the final draft summary report instead of with the required weekly and monthly monitoring reports. This is consistent with reporting requirements for the PCT and SFD IHAs. Typographical errors identified in tables 2 and 13 in the Federal Register notice of the proposed IHA have been corrected in this Federal Register notice of issuance (see tables 1 and 10, respectively). In addition, some clarifying language regarding source levels proposed for impact pile removal and pile splitting has been added to the Estimated Take section. Lastly, in the Endangered Species Act section of the Federal Register notice of the proposed IHA, NMFS omitted reference to the Western North Pacific DPS of humpback whales as a listed species under the ESA for which NMFS OPR was requesting ESA section 7 consultation. However, this species was considered in the formal consultation and is assessed in the BiOp issued by the NMFS Alaska Regional Office on December 15, 2023. No other changes have been made from the proposed IHA to the final IHA. Description of Marine Mammals in the Area of Specified Activities There are seven species of marine mammals that may be found in upper Cook Inlet during the planned construction and demolition activities. Sections 3 and 4 of the IHA application summarize available information regarding status and trends, distribution and habitat preferences, and behavior and life history of the potentially affected species. NMFS fully considered all of this information, and we refer the reader to these descriptions, instead of reprinting the information. Additional information regarding population trends and threats may be found in NMFS' Stock Assessment Reports (SARs; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments ) and more general information about these species ( e.g., physical and behavioral descriptions) may be found on NMFS' website ( https://www.fisheries.noaa.gov/find-species ). Additional information on CIBWs may be found in NMFS' 2016 Recovery Plan for the CIBW, available online at https://www.fisheries.noaa.gov/resource/document/recovery-plan-cook-inlet-beluga-whale-delphinapterus-leucas, and NMFS' 2023 report on the abundance and trend of CIBWs in Cook Inlet in June 2021 and June 2022, available online at https://www.fisheries.noaa.gov/resource/document/abundance-and-trend-belugas-delphinapterus-leucas-cook-inlet-alaska-june-2021-and. Table 2 lists all species or stocks for which take is expected and authorized for this activity, and summarizes information related to the population or stock, including regulatory status under the MMPA and ESA and potential biological removal (PBR), where known. PBR is defined by the MMPA as the maximum number of animals, not including natural mortalities, that may be removed from a marine mammal stock while allowing that stock to reach or maintain its optimum sustainable population (as described in NMFS' SARs). While no serious injury or mortality is anticipated or authorized here, PBR and annual serious injury and mortality from anthropogenic sources are included here as gross indicators of the status of the species or stocks and other threats. Marine mammal abundance estimates presented in this document represent the total number of individuals that make up a given stock or the total number estimated within a particular study or survey area. NMFS' stock abundance estimates for most species represent the total estimate of individuals within the geographic area, if known, that comprises that stock. For some species, this geographic area may extend beyond U.S. waters. All managed stocks in this region are assessed in NMFS' U.S. Alaska and Pacific SARs ( e.g., Carretta, et al., 2023; Young et al., 2023). Values presented in table 2 are the most recent available at the time of publication and are available online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments. The most recent abundance estimate for CIBWs, however, is available from Goetz et al. (2023) and available online at https://www.fisheries.noaa.gov/feature-story/new-abundance-estimate-endangered-cook-inlet-beluga-whales. BILLING CODE 3510-22-P EN16JA24.032 EN16JA24.033 BILLING CODE 3510-22-C On June 15, 2023, NMFS released an updated abundance estimate for endangered CIBWs in Alaska (Goetz et al., 2023) that incorporates aerial survey data from June 2021 and 2022, but which is not included in the most recent SAR (Young et al., 2023). Data collected during NMFS recent aerial survey effort suggest that the whale population is stable or may be increasing slightly. Goetz et al. (2023) estimated that the population size is currently between 290 and 386, with a median best estimate of 331. In accordance with the MMPA, this population estimate will be incorporated into the next draft CIBW SAR, which will be reviewed by an independent panel of experts, the Alaska Scientific Review Group. After this review, the SAR will be made available as a draft for public review before being finalized. We have determined that it is appropriate to consider the CIBW estimate of abundance reported by Goetz et al. (2023) in our analysis rather than the older estimate currently available from the Alaska SAR (Young et al., 2023) because it is based on the most recent and best available science. As indicated above, all seven species (with nine managed stocks) in table 2 temporally and spatially co-occur with the activity to the degree that take is reasonably likely to occur. Minke whales ( Balaenoptera acutorostrata ) and Dall's porpoises ( Phocoenoides dalli ) also occur in Cook Inlet; however, the spatial occurrence of these species is such that take is not expected to occur, and they are not discussed further beyond the explanation provided here. Data from the Alaska Marine Mammal Stranding Network database (NMFS, unpublished data) provide additional support for these determinations. From 2011 to 2020, only one minke whale and one Dall's porpoise were documented as stranded in the portion of Cook Inlet north of Point Possession. Both were dead upon discovery; it is unknown if they were alive upon their entry into upper Cook Inlet or drifted into the area with the tides. With very few exceptions, minke whales and Dall's porpoises do not occur in upper Cook Inlet, and therefore take of these species is considered unlikely. In addition, sea otters ( Enhydra lutris ) may be found in Cook Inlet. However, sea otters are managed by the U.S. Fish and Wildlife Service (USFWS) and are not considered further in this document. A detailed description of the species likely to be affected by the NES1 project, including a brief introduction to the affected stock as well as available information regarding population trends and threats, and information regarding local occurrence, were provided in the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 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. Please refer to that Federal Register notice for these descriptions. Please also refer to NMFS' website ( https://www.fisheries.noaa.gov/find-species ) for generalized species accounts. Marine Mammal Hearing Hearing is the most important sensory modality for marine mammals underwater, and exposure to anthropogenic sound can have deleterious effects. To appropriately assess the potential effects of exposure to sound, it is necessary to understand the frequency ranges marine mammals are able to hear. Not all marine mammal species have equal hearing capabilities ( e.g., Richardson et al., 1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect this, Southall et al. (2007, 2019) recommended that marine mammals be divided into hearing groups based on directly measured (behavioral or auditory evoked potential techniques) or estimated hearing ranges (behavioral response data, anatomical modeling, etc. ). Note that no direct measurements of hearing ability have been successfully completed for mysticetes ( i.e., low-frequency cetaceans). Subsequently, NMFS (2018) described generalized hearing ranges for these marine mammal hearing groups. Generalized hearing ranges were chosen based on the approximately 65-dB threshold from the normalized composite audiograms, with the exception for lower limits for low-frequency cetaceans where the lower bound was deemed to be biologically implausible and the lower bound from Southall et al. (2007) retained. Marine mammal hearing groups and their associated hearing ranges are provided in table 3. Specific to this action, gray whales and humpback whales are considered low-frequency (LF) cetaceans, CIBWs, and killer whales are considered mid-frequency (MF) cetaceans, harbor porpoises are considered high-frequency (HF) cetaceans, Steller sea lions are otariid pinnipeds, and harbor seals are phocid pinnipeds. BILLING CODE 3510-22-P EN16JA24.034 BILLING CODE 3510-22-C The pinniped functional hearing group was modified from Southall et al. (2007) on the basis of data indicating that phocid species have consistently demonstrated an extended frequency range of hearing compared to otariids, especially in the higher frequency range (Hemilä et al., 2006; Kastelein et al., 2009; Reichmuth and Holt, 2013). This division between phocid and otariid pinnipeds is now reflected in the updated hearing groups proposed in Southall et al. (2019). For more detail concerning these groups and associated frequency ranges, please see NMFS (2018) for a review of available information. Potential Effects of Specified Activities on Marine Mammals and Their Habitat The effects of underwater noise from the POA's construction activities have the potential to result in harassment of marine mammals in the vicinity of the POA. The Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023) included a discussion of the effects of anthropogenic noise on marine mammals and the potential effects of underwater noise from the POA's construction activities on marine mammals and their habitat. That information and analysis is referenced in this notice of issuance of the final IHA and is not repeated here; please refer to the notice of the proposed IHA (88 FR 76576, November 6, 2023). Estimated Take This section provides an estimate of the number of incidental takes authorized through the IHA, which will inform both NMFS' consideration of “small numbers,” and the negligible impact determinations. Harassment is the only type of take expected to result from these activities. Except with respect to certain activities not pertinent here, section 3(18) of the MMPA defines “harassment” as any act of pursuit, torment, or annoyance, which (i) has the potential to injure a marine mammal or marine mammal stock in the wild (Level A harassment); or (ii) has the potential to disturb a marine mammal or marine mammal stock in the wild by causing disruption of behavioral patterns, including, but not limited to, migration, breathing, nursing, breeding, feeding, or sheltering (Level B harassment). Authorized takes will primarily be by Level B harassment, as use of the acoustic sources ( i.e., vibratory and impact pile driving) has the potential to result in disruption of behavioral patterns for individual marine mammals. There is also some potential for auditory injury (Level A harassment) to result, primarily for HF cetaceans and phocids because predicted auditory injury zones are larger than for MF cetaceans and otariids. Auditory injury is unlikely to occur for mysticetes, MF cetaceans, and otariids due to measures described in the Mitigation section. The mitigation and monitoring measures are expected to minimize the severity of the taking to the extent practicable. As described previously, no serious injury or mortality is anticipated or authorized for this activity. Below we describe how the take numbers were estimated. For acoustic impacts, generally speaking, we estimate take by considering: (1) acoustic thresholds above which NMFS believes the best available science indicates marine mammals will be behaviorally harassed or incur some degree of permanent hearing impairment; (2) the area or volume of water that will be ensonified above these levels in a day; (3) the density or occurrence of marine mammals within these ensonified areas; and, (4) the number of days of activities. We note that while these factors can contribute to a basic calculation to provide an initial prediction of potential takes, additional information that can qualitatively inform take estimates is also sometimes available ( e.g., previous monitoring results or average group size). Below, we describe the factors considered here in more detail and present the take estimates. Acoustic Thresholds NMFS recommends the use of acoustic thresholds that identify the received level of underwater sound above which exposed marine mammals would be reasonably expected to be behaviorally harassed (equated to Level B harassment) or to incur PTS of some degree (equated to Level A harassment). Level B Harassment —Though significantly driven by received level, the onset of behavioral disturbance from anthropogenic noise exposure is also informed to varying degrees by other factors related to the source or exposure context ( e.g., frequency, predictability, duty cycle, duration of the exposure, signal-to-noise ratio, distance to the source), the environment ( e.g., bathymetry, other noises in the area, predators in the area), and the receiving animals (hearing, motivation, experience, demography, life stage, depth) and can be difficult to predict ( e.g., Southall et al., 2007, 2021; Ellison et al., 2012). Based on what the available science indicates and the practical need to use a threshold based on a metric that is both predictable and measurable for most activities, NMFS typically uses a generalized acoustic threshold based on received level to estimate the onset of behavioral harassment. NMFS generally predicts that marine mammals are likely to be behaviorally harassed in a manner considered to be Level B harassment when exposed to underwater anthropogenic noise above RMS SPL of 120-dB re 1 μPa for continuous ( e.g., vibratory pile driving, drilling) and above RMS SPL 160-dB re 1 μPa for non-explosive impulsive ( e.g., seismic airguns) or intermittent ( e.g., scientific sonar) sources. Generally speaking, Level B harassment take estimates based on these behavioral harassment thresholds are expected to include any likely takes by temporary threshold shift (TTS) as, in most cases, the likelihood of TTS occurs at distances from the source less than those at which behavioral harassment is likely. TTS of a sufficient degree can manifest as behavioral harassment, as reduced hearing sensitivity and the potential reduced opportunities to detect important signals (conspecific communication, predators, prey) may result in changes in behavior patterns that would not otherwise occur. The POA's planned activity includes the use of continuous (vibratory pile driving) and intermittent (impact pile driving) noise sources, and therefore the RMS SPL thresholds of 120- and 160-dB re 1 μPa are applicable. Level A Harassment. NMFS' Technical Guidance for Assessing the Effects of Anthropogenic Sound on Marine Mammal Hearing (Version 2.0; NMFS, 2018) identifies dual criteria to assess auditory injury (Level A harassment) to five different marine mammal groups (based on hearing sensitivity) as a result of exposure to noise from two different types of sources (impulsive or non-impulsive). The POA's planned activity includes the use of impulsive (impact pile driving) and non-impulsive (vibratory driving) sources. These thresholds are provided in the table below. The references, analysis, and methodology used in the development of the thresholds are described in NMFS' 2018 Technical Guidance, which may be accessed at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance. BILLING CODE 3510-22-P EN16JA24.035 BILLING CODE 3510-22-C 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 ( TL ) 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., impact pile removal and vibratory pile installation and removal). Calculation of the area ensonified by the specified action is dependent on the background sound levels at the project site, the source levels of the planned activities, and the estimated transmission loss coefficients for the planned activities at the site. These factors are addressed in order, below. Background Sound Levels at the Port of Alaska. As noted in the Potential Effects of Specified Activities on Marine Mammals and Their Habitat section of the Federal Register notice of the proposed IHA (88 FR 76576, November 6, 2023), the POA is an industrial facility in a location with high levels of commercial vessel traffic, port operations (including dredging), and extreme tidal flow. Previous measurements of background noise at the POA have recorded a background SPL of 122.2-dB RMS (Austin et al., 2016). NMFS concurred that this SPL reasonably represents background noise near the project area, and therefore we have used 122.2-dB RMS as the threshold for Level B harassment (instead of 120-dB RMS). Sound Source Levels of Specified Activities. The intensity of pile driving sounds is greatly influenced by factors such as the type of piles (material and diameter), hammer type, and the physical environment ( e.g., sediment type) in which the activity takes place. In order to calculate the distances to the Level A harassment and the Level B harassment sound thresholds for the methods and piles being used in this project, the POA used acoustic monitoring data from sound source verification studies to develop proxy source levels for the various pile types, sizes and methods (table 5). While site-specific sound source verification studies have been conducted at the POA, the vast majority of the measurements recorded in those studies were made when bubble curtains were deployed around the sound source, which act to attenuate sound levels (Austin et al., 2016; I&R, 2021a, 2021b). Bubble curtains are not a feasible mitigation measure for the NES1 project due to the demolition and sequencing nature of the project (see the Mitigation section of this notice for additional discussion), and therefore the majority of the proxy values for this project are based on measurements recorded from locations other than the POA. Underwater sound was measured in 2008 at the POA for the Marine Terminal Redevelopment Project (MTRP) during installation of sheet piles to assess potential impacts of sound on marine species. Sound levels for installation of sheet piles measured at 10-m typically ranged from 147- to 161-dB RMS, with a mean of approximately 155-dB RMS (James Reyff, unpublished data). An SPL of 162-dB RMS was reported in (California Department of Transportation (CALTRANS), 2020) summary tables for 24-inch (61-cm) steel sheet piles. This is a more rigid type of sheet pile that requires a large vibratory driver (James Reyff, personal communication, August 26, 2020). Based on the 2008 measurements at the POA and the CALTRANS data, a value of 160-dB RMS was assumed for vibratory removal of sheet piles. NMFS concurred that the source levels proposed by the POA for all pile sizes during impact removal and vibratory installation of all pile types are appropriate to use for calculating harassment isopleths for the POA's planned NES1 activities (table 5). Impact removal is the process of hitting a pile with an impact hammer with a small number of strikes (up to 50 per pile) to loosen it from the soil so that it can be removed via other means such as direct pulling or with a vibratory hammer. There are no data to our knowledge available on impact removal of this nature. The POA proposed to use SPL values measured during the impact installation of 24-inch (61-cm) AZ steel sheet piles from the Berth 23, Port of Oakland Project (CALTRANS, 2020) for this activity. Given this is the best available information, NMFS has accepted the POA's proposed SPLs for this activity. However, the source levels proposed by the POA for vibratory pile removal were based on limited data collected at the POA. Therefore, NMFS considered and evaluated all data related to unattenuated vibratory removal of 24-inch (61-cm) and 36-inch (91-cm) steel pipe piles available, including sound source verification data measured at the POA during the PCT project (Reyff et al., 2021a) and elsewhere ( i.e., Coleman, 2011; U.S. Navy, 2012; I&R, 2017). NMFS gathered data from publicly available reports that reported driving conditions and specified vibratory removal for certain piles. If vibratory removal was not specifically noted for a given pile, we excluded that data from the analysis. Mean RMS SPLs reported by these studies were converted into pressure values, and pressure values for piles from each project were averaged to give a single SPL for each project. The calculated project means were then averaged and converted back into dBs to give a single recommended SPL (rounded to the nearest whole dB) for each pile type. Ten measurements were available for unattenuated vibratory removal of 24-inch (61-cm) piles: 3 from Columbia River Crossing in Oregon (mean RMS SPL of 173-dB; Coleman, 2011), 5 from Joint Expeditionary Base Little Creek in Norfolk, Virginia (mean RMS SPL of 148-dB; I&R, 2017), and 2 from the PCT project at the POA (mean RMS SPL of 169-dB; I&R, 2021a, 2023). The calculated average SPL for unattenuated vibratory removal of 24-inch (61-cm) steel pipe piles from these studies was 169-dB RMS (table 5). Forty measurements were available for unattenuated vibratory removal of 36-inch (91-cm) piles: 38 from the U.S. Navy Test Pile Program at Naval Base Kitsap in Bangor, Washington (mean RMS SPL of 160-dB; U.S. Navy, 2012), and 2 from the PCT project at the POA (mean RMS SPL of 159-dB; I&R, 2021, 2023). The calculated average SPL for unattenuated vibratory removal of 36-inch (91-cm) steel pipe piles from these studies was 159-dB RMS (table 5). Note that the proxy values in table 5 represent SPL referenced at a distance of 10- m from the source. Interestingly, the RMS SPLs for the unattenuated vibratory removal of 24-inch (61-cm) piles were much louder than the unattenuated vibratory removal of 36-inch (91-cm) piles, and even louder than the unattenuated vibratory installation of 24-inch piles. I&R (2023) suggest that at least for data recorded at the POA, the higher 24-inch (61-cm) removal levels are likely due to the piles being removed at rates of 1,600 to 1,700 revolutions per minute (rpm), while 36-inch (91-cm) piles, which are significantly heavier than 24-inch (61-cm) piles), were removed at a rate of 1,900 rpm. The slower rates combined with the lighter piles would cause the hammer to easily “jerk” or excite the 24-inch (61-cm) piles as they were extracted, resulting in a louder rattling sound and louder sound levels. This did not occur for the 36-inch (91-cm) piles, which were considerably heavier due to increased diameter, longer length, and greater thickness. EN16JA24.036 A splitter will be used in conjunction with a vibratory hammer to make vertical cuts in sheet piles as necessary to help with their removal. The POA assumes that a pile splitter will produce the same or similar sound levels as a vibratory hammer without the splitter attachment; therefore, the POA combined use of a vibratory hammer to remove sheet pile and use of a spl [Text truncated at 120,000 characters. The full text is on the page linked above.] --- Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A2024-00511. Public record. Not legal advice.