Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Boost-Backs and Landings of Rockets at Vandenberg Air Force Base, 18574-18597 [2016-07191]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 81, Number 62 (Thursday, March 31, 2016)]
[Notices]
[Pages 18574-18597]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-07191]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XE443


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Boost-Backs and Landings of Rockets 
at Vandenberg Air Force Base

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Commerce.

ACTION: Notice; proposed incidental harassment authorization; request 
for comments.

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SUMMARY: NMFS has received a request from Space Explorations Technology 
Corporation (SpaceX), for authorization to take marine mammals 
incidental to boost-backs and landings of Falcon 9 rockets at 
Vandenberg Air Force Base in California, and at a contingency landing 
location approximately 30 miles offshore. Pursuant to the Marine Mammal 
Protection Act (MMPA), NMFS is requesting comments on its proposal to 
issue an incidental harassment authorization (IHA) to SpaceX to 
incidentally take marine mammals, by Level B Harassment only, during 
the specified activity.

DATES: Comments and information must be received no later than May 2, 
2016.

ADDRESSES: Comments on the application should be addressed to Jolie 
Harrison, Chief, Permits and Conservation Division, Office of Protected 
Resources, National Marine Fisheries Service. Physical comments should 
be sent to 1315 East-West Highway, Silver Spring, MD 20910 and 
electronic comments should be sent to ITP.Carduner@noaa.gov.
    Instructions: Comments sent by any other method, to any other 
address or individual, or received after the end of the comment period, 
may not be considered by NMFS. Comments received electronically, 
including all attachments, must not exceed a 25-megabyte file size. 
Attachments to electronic comments will be accepted in Microsoft Word 
or Excel or Adobe PDF file formats only. All comments received are a 
part of the public record and will generally be posted for public 
viewing on the Internet at www.nmfs.noaa.gov/pr/permits/incidental/ 
without change. All personal identifying information (e.g., name, 
address), confidential business information, or otherwise sensitive 
information submitted voluntarily by the sender will be publicly 
accessible.

FOR FURTHER INFORMATION CONTACT: Jordan Carduner, Office of Protected 
Resources, NMFS, (301) 427-8401.

SUPPLEMENTARY INFORMATION:

Availability

    An electronic copy of SpaceX's IHA application and supporting 
documents, as well as a list of the references cited in this document, 
may be obtained by visiting the Internet at www.nmfs.noaa.gov/pr/permits/incidental/. In case of problems accessing these documents, 
please call the contact listed under FOR FURTHER INFORMATION CONTACT.

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct the Secretary of Commerce to allow, upon request by U.S. 
citizens who engage in a specified activity (other than commercial 
fishing) within a specified area, the incidental, but not intentional, 
taking of small numbers of marine mammals, providing that certain 
findings are made and the necessary prescriptions are established.
    The incidental taking of small numbers of marine mammals may be 
allowed only if NMFS (through authority delegated by the Secretary) 
finds that the total taking by the specified activity during the 
specified time period will (i) have a negligible impact on the species 
or stock(s) and (ii) not have an unmitigable adverse impact on the 
availability of the species or stock(s) for subsistence uses (where 
relevant). Further, the permissible methods of taking and requirements 
pertaining to the mitigation, monitoring and reporting of such taking 
must be set forth.
    The allowance of such incidental taking under section 101(a)(5)(A), 
by harassment, serious injury, death, or a combination thereof, 
requires that regulations be established. Subsequently, a Letter of 
Authorization may be issued pursuant to the prescriptions established 
in such regulations, providing that the level of taking will be 
consistent with the findings made for the total taking allowable under 
the specific regulations. Under section 101(a)(5)(D), NMFS may 
authorize such incidental taking by harassment only, for periods of not 
more than one year, pursuant to requirements and conditions contained 
within an IHA. The establishment of these prescriptions requires notice 
and opportunity for public comment.
    NMFS has defined ``negligible impact'' in 50 CFR 216.103 as ``. . . 
an impact resulting from the specified activity that cannot be 
reasonably

[[Page 18575]]

expected to, and is not reasonably likely to, adversely affect the 
species or stock through effects on annual rates of recruitment or 
survival.'' 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].''

Summary of Request

    On July 28, 2015, we received a request from SpaceX for 
authorization to take marine mammals incidental to Falcon 9 First Stage 
recovery activities, including in-air boost-back maneuvers and landings 
of the First Stage of the Falcon 9 rocket at Vandenberg Air Force Base 
(VAFB) in California, and at a contingency landing location 
approximately 50 km (31 mi) offshore of VAFB. SpaceX submitted a 
revised version of the request on November 5, 2015. This revised 
version of the application was deemed adequate and complete. Acoustic 
stimuli, including sonic booms (overpressure of high-energy impulsive 
sound), landing noise, and possible explosions, resulting from boost-
back maneuvers and landings of the Falcon 9 First Stage have the 
potential to result in take, in the form of Level B harassment, of six 
species of pinnipeds. NMFS is proposing to authorize the Level B 
harassment of the following marine mammal species/stocks, incidental to 
SpaceX's proposed activities: Pacific harbor seal (Phoca vitulina 
richardii), California sea lion (Zalophus californianus), Steller sea 
lion (eastern Distinct Population Segment, or DPS) (Eumetopias 
jubatus), northern elephant seal (Mirounga angustirostris), northern 
fur seal (Callorhinus ursinus), and Guadalupe fur seal (Arctocephalus 
townsendi).

Description of the Specified Activity

Overview

    The Falcon 9 is a two-stage rocket designed and manufactured by 
SpaceX for transport of satellites and SpaceX's Dragon spacecraft into 
orbit. SpaceX currently operates the Falcon Launch Vehicle Program at 
Space Launch Complex 4E (SLC-4E) at VAFB. SpaceX proposes regular 
employment of First Stage recovery by returning the Falcon 9 First 
Stage to SLC-4 West (SLC-4W) at VAFB for potential reuse up to six 
times per year. The reuse of the Falcon 9 First Stage will enable 
SpaceX to efficiently conduct lower cost launch missions from VAFB in 
support of commercial and government clients. First Stage recovery 
includes an in-air boost-back maneuver and the landing of the First 
Stage of the Falcon 9 rocket.
    Although SLC-4W is the preferred landing location, SpaceX has 
identified the need for a contingency landing action that would only be 
exercised if there were critical assets on South VAFB that would not 
permit an over-flight of the First Stage, or if other reasons such as 
fuel constraints did not permit landing at SLC-4W. The contingency 
action is to land the First Stage on a barge in the Pacific Ocean at a 
landing location 50 km (31 miles) offshore of VAFB.

Dates and Duration

    SpaceX plans to conduct their proposed activities during the period 
from June 30, 2016 to June 29, 2017. Up to six Falcon 9 First Stage 
recovery activities would occur per year. Precise dates of Falcon 9 
First Stage recovery activities are not known. Falcon 9 First Stage 
recovery activities may take place at any time of year and at any time 
of day.

Specific Geographic Region

    Falcon 9 First Stage recovery activities will originate at VAFB. 
Areas affected include VAFB and areas on the coastline surrounding 
VAFB; the Pacific Ocean offshore VAFB; and the Northern Channel Islands 
(NCI). VAFB operates as a missile test base and aerospace center, 
supporting west coast space launch activities for the U.S. Air Force 
(USAF), Department of Defense, National Aeronautics and Space 
Administration, and commercial contractors. VAFB is the main west coast 
launch facility for placing commercial, government, and military 
satellites into polar orbit on expendable (unmanned) launch vehicles, 
and for testing and evaluating intercontinental ballistic missiles and 
sub-orbital target and interceptor missiles.
    VAFB occupies approximately 99,100 acres of central Santa Barbara 
County, California (see Figure 1-1 in SpaceX's IHA application), 
approximately halfway between San Diego and San Francisco. The Santa 
Ynez River and State Highway 246 divide VAFB into two distinct parts: 
North Base and South Base. SLC-4W is located on South Base, 
approximately 0.5 miles (0.8 km) inland from the Pacific Ocean (see 
Figure 1-2 in SpaceX's IHA application). SLC-4E, the launch facility 
for SpaceX's Falcon 9 program, is located approximately 427 m to the 
east of SLC-4W, the proposed landing site for the Falcon 9 First Stage 
(see Figure 1-2, inset, in SpaceX's IHA application).
    Although SLC-4W is the preferred landing location, SpaceX has 
identified the need for a contingency landing action that would be 
exercised if there were critical assets on South VAFB that would not 
permit an over-flight of the First Stage or if other reasons (e.g. fuel 
constraints) prevented a landing at SLC-4W. The contingency action is 
to land the First Stage on a barge in the Pacific Ocean at a landing 
location 31 miles (50 km) offshore of VAFB (see Figure 1-5 in SpaceX's 
IHA application for the proposed location of the contingency landing 
location). Thus the waters of the Pacific Ocean between VAFB and the 
area approximately 50 km offshore shown in Figure 1-5 in SpaceX's IHA 
application are also considered part of the project area for the 
purposes of this proposed authorization.
    The NCI are four islands (San Miguel, Santa Rosa, Santa Cruz, and 
Anacapa) located approximately 50 km (31 mi) south of Point Conception, 
which is located on the mainland approximately 6.5 km south of the 
southern border of VAFB (see Figure 2-1 and 2-2 in the IHA 
application). All four islands are inhabited by pinnipeds, with San 
Miguel Island being the most actively used among the four islands for 
pinniped rookeries. All four islands in the NCI are part of the Channel 
Islands National Park, while the Channel Islands National Marine 
Sanctuary encompasses the waters 11 km off the islands. The closest 
part of the NCI (Harris Point on San Miguel Island) is located more 
than 55 km south-southeast of SLC-4E, the launch facility for the 
Falcon 9 rocket. Pinnipeds hauled out on beaches of the NCI may be 
affected by sonic booms associated with the proposed action, as 
described later in this document.

Detailed Description of Activities

    The Falcon 9 is a two-stage rocket designed and manufactured by 
SpaceX for transport of satellites and SpaceX's Dragon spacecraft into 
orbit. The First Stage of the Falcon 9 is designed to be reusable, 
while the second stage is not reusable. The proposed action includes up 
to six Falcon 9 First Stage recoveries, including in-air boost-back 
maneuvers and landings of the First Stage, at VAFB and/or at a 
contingency landing location 50 km offshore over the course of one 
year.

[[Page 18576]]

Boost-back and Landing Maneuvers

    After launch of the Falcon 9, the boost-back and landing sequence 
begins when the rocket's First Stage separates from the second stage 
and the Merlin engines of the First Stage cut off. After First Stage 
engine cutoff, rather than dropping the First Stage in the Pacific 
Ocean, exoatmospheric cold gas thrusters would be triggered to flip the 
First Stage into position for retrograde burn. The First Stage would 
then descend back toward earth. During descent, a sonic boom would be 
generated when the First Stage reaches a rate of travel that exceeds 
the speed of sound. Sound from the sonic boom would have the potential 
to result in harassment of marine mammals, as described below. The 
sonic boom's overpressure would be directed at either the coastal area 
south of SLC-4 or at the ocean surface no less than 50 km off the coast 
of VAFB, depending on the targeted landing location. Three of the nine 
First Stage Merlin engines would be restarted to conduct the retrograde 
burn in order to reduce the velocity of the First Stage in the correct 
angle to land. Once the First Stage is in position and approaching its 
landing target, the three engines would be cut off to end the boost-
back burn. The First Stage would then perform a controlled descent 
using atmospheric resistance to slow the stage down and guide it to the 
landing site. The landing legs on the First Stage would then deploy in 
preparation for a final single engine burn that would slow the First 
Stage to a velocity of zero before landing. Please see Figure 1-3 in 
the IHA application for a graphical depiction of the boost-back and 
landing sequence, and see Figure 1-4 in the IHA application for an 
example of the boost-back trajectory of the First Stage and the second 
stage trajectory.

Contingency Landing Procedure

    As a contingency action to landing the Falcon 9 First Stage on the 
SLC-4W landing pad at VAFB, SpaceX proposes to return the Falcon 9 
First Stage booster to a barge. The barge is specifically designed to 
be used as a First Stage landing platform and will be located at least 
50 km off VAFB's shore (See Figure 1-5 in the IHA application). The 
contingency landing location would be used if conditions prevented a 
landing at SLC-4W, as described above. The maneuvering and landing 
process described above for a pad landing would be the same for a barge 
landing. Three vessels would be required to support a barge landing, if 
it were required: A barge/landing platform (300 ft long and 150 ft 
wide); a support vessel (165 ft long research vessel); and an ocean tug 
(120 ft long open water commercial tug). In the event of an 
unsuccessful barge landing, the First Stage would explode upon impact 
with the barge; the explosion would not be expected to result in take 
of marine mammals, as described below. The explosive equivalence with 
maximum fuel and oxidizer is 503 pounds of trinitrotoluene (TNT) which 
is capable of a maximum projectile range of 384 m (1,250 ft) from the 
point of impact. Approximately 25 pieces of debris are expected to 
remain floating in the water and expected to impact less than 0.46 
km\2\ (114 acres), and the majority of debris would be recovered. All 
other debris is expected to sink. These 25 pieces of debris are 
primarily made of Carbon Over Pressure Vessels (COPVs), the LOX fill 
line, and carbon fiber constructed legs. During previous landing 
attempts in other locations, SpaceX has performed successful debris 
recovery. All of the recovered debris would be transported back to Long 
Beach Harbor for proper disposal. Most of the fuel (estimated 50-150 
gallons) is expected to be released onto the barge deck at the location 
of impact.
    In the event that a contingency landing action is required, SpaceX 
has considered the likelihood of the First Stage missing the barge and 
landing instead in the Pacific Ocean, and has determined that the 
likelihood of such an event is so unlikely as to be considered 
discountable. This is supported by three previous attempts by SpaceX at 
Falcon 9 First Stage barge landings, none of which have missed the 
barge. Therefore, NMFS does not propose to authorize take of marine 
mammals incidental to landings of the Falcon 9 First Stage in the 
Pacific Ocean, and the potential effects of landings of the Falcon 9 
First Stage in the Pacific Ocean on marine mammals are not considered 
further in this proposed authorization.
    NMFS has previously issued regulations and Letters of Authorization 
(LOA) that authorize the take of marine mammals, by Level B harassment, 
incidental to launches of up to 50 rockets per year (including the 
Falcon 9) from VAFB (79 FR 10016). The regulations, titled ``Taking of 
Marine Mammals Incidental to U.S. Air Force Launches, Aircraft and 
Helicopter Operations, and Harbor Activities Related to Vehicles from 
Vandenberg Air Force Base, California,'' published February 24, 2014, 
are effective from March 2014 to March 2019. The activities proposed by 
SpaceX are limited to Falcon 9 First Stage recovery events (Falcon 9 
boost-back maneuvers and landings); launches of the Falcon 9 rocket are 
not part of the proposed activities, and incidental take (Level B 
harassment) resulting from Falcon 9 rocket launches from VAFB is 
already authorized in the above referenced LOA. As such, NMFS does not 
propose to authorize take of marine mammals incidental to launches of 
the Falcon 9 rocket; incidental take resulting from Falcon 9 rocket 
launches is therefore not analyzed further in this document. The LOA 
application (USAF 2013a), and links to the Federal Register notice of 
the final rule (79 FR 10016) and the Federal Register notice of 
issuance of the LOA (79 FR 18528), can be found on the NMFS Web site 
at: https://www.nmfs.noaa.gov/pr/permits/incidental.

Description of Marine Mammals in the Area of the Specified Activity

    There are six marine mammal species with expected occurrence in the 
project area (including at VAFB, on the NCI, and in the waters 
surrounding VAFB, the NCI and the contingency landing location) that 
are expected to be affected by the specified activities. These include 
the Steller sea lion (Eumetopias jubatus), northern fur seal 
(Callorhinus ursinus), northern elephant seal (Mirounga 
angustirostris), Guadalupe fur seal (Arctocephalus townsendi), 
California sea lion (Zalophus californianus), and Pacific harbor seal 
(Phoca vitulina richardsi). There are an additional 28 species of 
cetaceans with expected or possible occurrence in the project area. 
However, despite the fact that the ranges of these cetacean species 
overlap spatially with SpaceX's proposed activities, we have determined 
that none of the potential stressors associated with the proposed 
activities (including exposure to debris strike, rocket fuel, and 
visual and acoustic stimuli, as described further in ``Potential 
Effects of the Specified Activity on Marine Mammals'') are likely to 
result in take of cetaceans. As we have concluded that the likelihood 
of a cetacean being taken incidentally as a result of SpaceX's proposed 
activities is so low as to be discountable, cetaceans are not 
considered further in this proposed authorization. Please see Table 3-1 
in the IHA application for a complete list of species with expected or 
potential occurrence in the project area.
    We have reviewed SpaceX's detailed species descriptions, including 
abundance, status, distribution and life history information, for 
accuracy and completeness; this information is summarized below and may 
be viewed

[[Page 18577]]

in detail in the IHA application, available on the NMFS Web site at 
https://www.nmfs.noaa.gov/pr/permits/incidental. Additional information 
on these species is available in the NMFS stock assessment reports 
(SARs), which can be viewed online at https://www.nmfs.noaa.gov/pr/sars/. Generalized species accounts are also available on NMFS' Web 
site at www.nmfs.noaa.gov/pr/species/mammals.
    Table 1 lists the marine mammal species with expected potential for 
occurrence in the vicinity of the project during the project timeframe 
that are likely to be affected by the specified activities, and 
summarizes key information regarding stock status and abundance. Please 
see NMFS' Stock Assessment Reports (SAR), available at 
www.nmfs.noaa.gov/pr/sars, for more detailed accounts of these stocks' 
status and abundance.

  Table 1--Marine Mammals Expected To be Present in the Vicinity of the Project Location That are Likely To be
                                      Affected by the Specified Activities
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                                                          ESA Status/MMPA
             Species                      Stock          Status; strategic        Stock         Occurrence in
                                                              (Y/N)\1\        abundance \2\      project area
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                                     Order Carnivora--Superfamily Pinnipedia
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                                  Family Otariidae (eared seals and sea lions)
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Steller sea lion.................  Eastern U.S. DPS...  -/D; Y.............          60,131  Rare.
California sea lion..............  U.S. stock.........  -/-; N.............         296,750  Common.
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                                         Family Phocidae (earless seals)
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Harbor seal......................  California stock...  -/-; N.............          30,968  Common.
Northern elephant seal...........  California breeding  -/-; N.............         179,000  Common.
                                    stock.
Northern fur seal................  California stock...  -/-; N.............          12,844  Common.
Guadalupe fur seal...............  n/a................  T/D; Y.............         3 7,408  Rare.
----------------------------------------------------------------------------------------------------------------
1 ESA status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is
  not listed under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one
  for which the level of direct human-caused mortality exceeds PBR or is determined to be declining and likely
  to be listed under the ESA within the foreseeable future. Any species or stock listed under the ESA is
  automatically designated under the MMPA as depleted and as a strategic stock.
2 For certain stocks of pinnipeds, abundance estimates are based upon observations of animals (often pups)
  ashore multiplied by some correction factor derived from knowledge of the species (or similar species) life
  history to arrive at a best abundance estimate.
3 Abundance estimate for this stock is greater than ten years old and is therefore not considered current. We
  nevertheless present the most recent abundance estimate, as this represents the best available information for
  use in this document.

    In the species accounts provided here, we offer a brief 
introduction to the species and relevant stock as well as available 
information regarding population trends and threats, and describe any 
information regarding local occurrence.

Pacific Harbor Seal

    Pacific harbor seals are the most common marine mammal inhabiting 
VAFB, congregating on multiple rocky haulout sites along the VAFB 
coastline. Harbor seals are local to the area, rarely traveling more 
than 50 km from haul-out sites. There are 12 harbor seal haul-out sites 
on south VAFB; of these, 10 sites represent an almost continuous haul-
out area which is used by the same animals. Virtually all of the haul-
out sites at VAFB are used during low tides and are wave-washed or 
submerged during high tides. Additionally, the Pacific harbor seal is 
the only species that regularly hauls out near the VAFB harbor. The 
main harbor seal haul-outs on VAFB are near Purisima Point and at 
Lion's Head (approximately 0.6 km south of Point Sal) on north VAFB and 
between the VAFB harbor north to South Rocky Point Beach on south VAFB 
(ManTech 2009). This south VAFB haul-out area is composed of several 
sand and cobblestone coves, rocky ledges, and offshore rocks. The Rocky 
Point area, located approximately 1.6 km north of the VAFB harbor, is 
used as breeding habitat (ManTech 2009).
    Pups are generally present in the region from March through July. 
Within the affected area on VAFB, a total of up to 332 adults and 34 
pups have been recorded, at all haulouts combined, in monthly counts 
from 2013 to 2015 (ManTech 2015). During aerial pinniped surveys of 
haulouts located in the Point Conception area by NOAA Fisheries in May 
2002 and May and June of 2004, between 488 to 516 harbor seals were 
recorded (M. Lowry, NOAA Fisheries, unpubl. data). Harbor seals also 
haul out, breed, and pup in isolated beaches and coves throughout the 
coasts of San Miguel, Santa Rosa, and Santa Cruz Islands (Lowry 2002). 
During aerial surveys conducted by NOAA Fisheries in May 2002 and May 
and June of 2004, between 521 and 1,004 harbors seals were recorded at 
San Miguel Island, between 605 and 972 at Santa Rosa Island, and 
between 599 and 1,102 Santa Cruz Island (M. Lowry, NOAA Fisheries, 
unpubl. data).
    The harbor seal population at VAFB has undergone an apparent 
decline in recent years (USAF 2013). This decline has been attributed 
to a series of natural landslides at south VAFB, resulting in the 
abandonment of many haulout sites. These slides have also resulted in 
extensive down-current sediment deposition, making these sites 
accessible to coyotes, which are now regularly seen in the area. Some 
of the displaced seals have moved to other sites at south VAFB, while 
others likely have moved to Point Conception, about 6.5 km south of the 
southern boundary of VAFB.
    Pacific harbor seals frequently use haul-out sites on the NCI, 
including San Miguel, Santa Rosa, Santa Cruz; and Anacapa. On San 
Miguel Island, they occur along the north coast at Tyler Bight and from 
Crook Point to Cardwell Point. Additionally, they regularly breed on 
San Miguel Island. On Santa Cruz Island, they inhabit small coves and 
rocky ledges along much of the coast. Harbor seals are scattered 
throughout Santa Rosa Island and also are observed in small numbers on 
Anacapa Island.

California Sea Lions

    California sea lions are not listed as threatened or endangered 
under the Endangered Species Act, nor are they categorized as depleted 
under the

[[Page 18578]]

Marine Mammal Protection Act. The estimated population of the U.S. 
stock is approximately 296,750 (Carretta et al. 2015). California sea 
lion breeding areas are on islands located in southern California, in 
western Baja California (Mexico), and the Gulf of California. During 
the breeding season, most California sea lions inhabit southern 
California and Mexico. Rookery sites in southern California are limited 
to the San Miguel Islands and the southerly Channel Islands of San 
Nicolas, Santa Barbara, and San Clemente (Carretta et al., 2015). Males 
establish breeding territories during May through July on both land and 
in the water. Females come ashore in mid-May and June where they give 
birth to a single pup approximately four to five days after arrival and 
will nurse pups for about a week before going on their first feeding 
trip. Adult and juvenile males will migrate as far north as British 
Columbia, Canada while females and pups remain in southern California 
waters in the non-breeding season. In warm water (El Ni[ntilde]o) 
years, some females are found as far north as Washington and Oregon, 
presumably following prey. Elevated strandings of California sea lion 
pups have occurred in Southern California since January 2013. This 
event has been declared an Unusual Mortality Event (UME), and is 
confined to pup and yearling California sea lions.
    California sea lions are common offshore of VAFB and haul out on 
rocks and beaches along the coastline of VAFB. At south VAFB, 
California sea lions haul out on north Rocky Point, with numbers often 
peaking in spring. They have been reported at Point Arguello and Point 
Pedernales (both on south VAFB) in the past, although none have been 
noted there over the past several years. Individual sea lions have been 
noted hauled out throughout the VAFB coast; these were transient or 
stranded specimens. California sea lions occasionally haul out on Point 
Conception itself, south of VAFB. They regularly haul out on Lion Rock, 
north of VAFB and immediately south of Point Sal. In 2014, counts of 
California sea lions at haulouts on VAFB increased substantially, 
ranging from 47 to 416 during monthly counts. Despite their prevalence 
at haulout sites at VAFB, California sea lions rarely pup on the VAFB 
coastline (ManTech 2015); no pups were observed in 2013 or 2014 
(ManTech 2015) and 1 pup was observed in 2015 (VAFB, unpubl. data).
    Pupping occurs in large numbers on San Miguel Island at the 
rookeries found at Point Bennett on the west end of the island and at 
Cardwell Point on the east end of the island (Lowry 2002). Sea lions 
haul out at the west end of Santa Rosa Island at Ford Point and 
Carrington Point. A few California sea lions have been born on Santa 
Rosa Island, but no rookery has been established. On Santa Cruz Island, 
California sea lions haul out from Painted Cave almost to Fraser Point, 
on the west end. Fair numbers haul out at Gull Island, off the south 
shore near Punta Arena. Pupping appears to be increasing there. Sea 
lions also haul out near Potato Harbor, on the northeast end of Santa 
Cruz. California sea lions haul out by the hundreds on the south side 
of East Anacapa Island.
    During aerial surveys conducted by NOAA Fisheries in February 2010 
of the Northern Channel Islands, 21,192 total California sea lions 
(14,802 pups) were observed at haulouts on San Miguel Island and 8,237 
total (5,712 pups) at Santa Rosa Island (M. Lowry, NOAA Fisheries, 
unpubl. data). During aerial surveys in July 2012, 65,660 total 
California sea lions (28,289 pups) were recorded at haulouts on San 
Miguel Island, 1,584 total (3 pups) at Santa Rosa Island, and 1,571 
total (zero pups) at Santa Cruz Island (M. Lowry, NOAA Fisheries, 
unpubl. data).

Northern Elephant Seal

    Northern elephant seals are not listed as threatened or endangered 
under the Endangered Species Act, nor are they categorized as depleted 
under the Marine Mammal Protection Act. The estimated population of the 
California breeding stock is approximately 179,000 animals (Carretta et 
al. 2015). Northern elephant seals range in the eastern and central 
North Pacific Ocean, from as far north as Alaska and as far south as 
Mexico. They spend much of the year, generally about nine months, in 
the ocean. They spend much of their lives underwater, diving to depths 
of about 1,000 to 2,500 ft (330-800 m) for 20- to 30-minute intervals 
with only short breaks at the surface, and are rarely seen at sea for 
this reason. While on land, they prefer sandy beaches.
    Northern elephant seals breed and give birth in California and Baja 
California (Mexico), primarily on offshore islands, from December to 
March (Stewart et al. 1994). Adults return to land between March and 
August to molt, with males returning later than females. Adults return 
to their feeding areas again between their spring/summer molting and 
their winter breeding seasons.
    Northern elephant seals haul out sporadically on rocks and beaches 
along the coastline of VAFB; monthly counts in 2013 and 2014 recorded 
between 0 and 191 elephant seals within the affected area (ManTech 
2015). However, northern elephant seals do not currently pup on the 
VAFB coastline. Observations of young of the year seals from May 
through November at VAFB have represented individuals dispersing later 
in the year from other parts of the California coastline where breeding 
and birthing occur. The nearest regularly used haul-out site on the 
mainland coast is at Point Conception. Eleven northern elephant seals 
were observed during aerial surveys of the Point Conception area by 
NOAA Fisheries in February of 2010 (M. Lowry, NOAA Fisheries, unpubl. 
data). In December 2012, an immature male elephant seal was observed 
hauled out on the sandy beach west of the breakwater at the VAFB harbor 
(representing the first documented instance of an elephant seal hauled 
out at the VAFB harbor). There has been no verified breeding of 
northern elephant seals on VAFB.
    Point Bennett on the west end of San Miguel Island is the primary 
northern elephant seal rookery in the NCI, with another rookery at 
Cardwell Point on the east end of San Miguel Island (Lowry 2002). They 
also pup and breed on Santa Rosa Island, mostly on the west end. 
Northern elephant seals are rarely seen on Santa Cruz and Anacapa 
Islands. During aerial surveys of the NCI conducted by NMFS in February 
2010, 21,192 total northern elephant seals (14,802 pups) were recorded 
at haulouts on San Miguel Island and 8,237 total (5,712 pups) were 
observed at Santa Rosa Island (M. Lowry, NOAA Fisheries, unpubl. data). 
None were observed at Santa Cruz Island (M. Lowry, NOAA Fisheries, 
unpubl. data).

Steller Sea Lion

    The eastern DPS of Steller sea lion is not listed as endangered or 
threatened under the ESA, nor is it categorized as depleted under the 
MMPA. The species as a whole was ESA-listed as threatened in 1990 (55 
FR 49204). In 1997, the species was divided into western and eastern 
DPSs, with the western DPS reclassified as endangered under the ESA and 
the eastern DPS retaining its threatened listing (62 FR 24345). On 
October 23, 2013, NMFS found that the eastern DPS has recovered; as a 
result of the finding, NMFS removed the eastern DPS from ESA listing. 
Only the eastern DPS is considered in this proposed authorization due 
to its distribution and the geographic scope of the action. Steller sea 
lions are distributed mainly around the coasts to the outer continental 
shelf along the North Pacific rim from northern Hokkaido, Japan through 
the Kuril Islands and Okhotsk Sea, Aleutian Islands and central Bering

[[Page 18579]]

Sea, southern coast of Alaska and south to California (Loughlin et al., 
1984).
    Prior to 2012, there were no records of Steller sea lions observed 
at VAFB. In April and May 2012, Steller sea lions were observed hauled 
out at North Rocky Point on VAFB, representing the first time the 
species had been observed on VAFB during launch monitoring and monthly 
surveys conducted over the past two decades (Marine Mammal Consulting 
Group and Science Applications International Corporation 2013). Since 
2012, Steller sea lions have been observed frequently in routine 
monthly surveys, with as many as 16 individuals recorded. In 2014, up 
to five Steller sea lions were observed in the affected area during 
monthly marine mammal counts (ManTech 2015) and a maximum of 12 
individuals were observed during monthly counts in 2015 (VAFB, 
unpublished data). However, up to 16 individuals were observed in 2012 
(SAIC 2012). Steller sea lions once had two small rookeries on San 
Miguel Island, but these were abandoned after the 1982-1983 El 
Ni[ntilde]o event (DeLong and Melin 2000; Lowry 2002); these rookeries 
were once the southernmost colonies of the eastern stock of this 
species. In recent years, between two to four juvenile and adult males 
have been observed on a somewhat regular basis on San Miguel Island 
(pers. comm. Sharon Melin, NMFS Alaska Fisheries Science Center, to J. 
Carduner, NMFS, Feb 11, 2016). Steller sea lions are not observed on 
the other NCI.

Northern Fur Seal

    Northern fur seals are not ESA listed and are not categorized as 
depleted under the MMPA. Northern fur seals occur from southern 
California north to the Bering Sea and west to the Okhotsk Sea and 
Honshu Island, Japan. Two stocks of northern fur seals are recognized 
in U.S. waters: An eastern Pacific stock and a California stock 
(formerly referred to as the San Miguel Island stock). Only the 
California stock is considered in this proposed authorization due to 
its geographic distribution.
    Due to differing requirements during the annual reproductive 
season, adult males and females typically occur ashore at different, 
though overlapping, times. Adult males occur ashore and defend 
reproductive territories during a 3-month period from June through 
August, though some may be present until November (well after giving up 
their territories). Adult females are found ashore for as long as 6 
months (June-November). After their respective times ashore, fur seals 
of both sexes spend the next 7 to 8 months at sea (Roppel 1984). Peak 
pupping is in early July and pups are weaned at three to four months. 
Some juveniles are present year-round, but most juveniles and adults 
head for the open ocean and a pelagic existence until the next year. 
Northern fur seals exhibit high site fidelity to their natal rookeries.
    Northern fur seals have rookeries on San Miguel Island at Point 
Bennett and on Castle Rock. Comprehensive count data for northern fur 
seals on San Miguel Island are not available. San Miguel Island is the 
only island in the NCI on which Northern fur seals have been observed. 
Although the population at San Miguel Island was established by 
individuals from Alaska and Russian Islands during the late 1960s, most 
individuals currently found on San Miguel nowadays are considered 
resident to the island. No haul-out or rookery sites exist for northern 
fur seals on the mainland coast. The only individuals that do appear on 
mainland beaches are stranded animals.

Guadalupe Fur Seal

    Guadalupe fur seals are listed as threatened under the ESA and are 
categorized as depleted under the MMPA. The population is estimated at 
7,408 animals; however, this estimate is over 20 years old (Carretta et 
al. 2015). The population is considered to be a single stock. Guadalupe 
Fur Seals were abundant prior to seal exploitation, when they were 
likely the most abundant pinniped species on the Channel Islands. They 
are found along the west coast of the United States, but are considered 
uncommon in Southern California. They are typically found on shores 
with abundant large rocks, often at the base of large cliffs (Belcher 
and Lee 2002). Increased strandings of Guadalupe fur seals started 
occurring along the entire coast of California in early 2015. 
Strandings were eight times higher than the historical average, peaking 
from April through June 2015, and have since lessened. This event has 
been declared a marine mammal UME.
    Comprehensive survey data on Guadalupe fur seals in the NCI is not 
readily available. On San Miguel Island, one to several male Guadalupe 
fur seals had been observed annually between 1969 and 2000 (DeLong and 
Melin 2000) and juvenile animals of both sexes have been seen 
occasionally over the years (Stewart et al. 1987). The first adult 
female at San Miguel Island was seen in 1997. In June 1997, she gave 
birth to a pup in rocky habitat along the south side of the island and, 
over the next year, reared the pup to weaning age. This was apparently 
the first pup born in the California Channel Islands in at least 150 
years. Since 2008, individual adult females, subadult males, and 
between one and three pups have been observed annually on San Miguel 
Island. There are estimated to be approximately 20-25 individuals that 
have fidelity to San Miguel, mostly inhabiting the southwest and 
northwest ends of the island. A total of 14 pups have been born on the 
island since 2009, with no more than 3 born in any single season (pers. 
comm., S. Melin, NMFS National Marine Mammal Laboratory, to J. 
Carduner, NMFS, Aug. 28, 2015). Thirteen individuals and two pups were 
observed in 2015 (NMFS 2016). No haul-out or rookery sites exist for 
Guadalupe fur seals on the mainland coast, including VAFB. The only 
individuals that do appear on mainland beaches are stranded animals.

Potential Effects of the Specified Activity on Marine Mammals

    This section includes a summary and discussion of the ways that 
components of the specified activity may impact marine mammals. The 
``Estimated Take by Incidental Harassment'' section later in this 
document will include a quantitative analysis of the number of 
individuals that are expected to be taken by this activity. The 
``Negligible Impact Analysis'' section will include the analysis of how 
this specific activity will impact marine mammals and will consider the 
content of this section, the ``Estimated Take by Incidental 
Harassment'' section, the ``Proposed Mitigation'' section, and the 
``Anticipated Effects on Marine Mammal Habitat'' section to draw 
conclusions regarding the likely impacts of this activity on the 
reproductive success or survivorship of individuals and from that on 
the affected marine mammal populations or stocks.

Debris Strike

    Under the contingency barge landing action, in the event of an 
unsuccessful barge landing, the First Stage booster is expected to 
explode upon impact with the barge. The maximum estimated remaining 
fuel and oxidizer onboard the booster when it explodes would be the 
equivalent a net explosive weight of 503 lbs. of TNT. The resulting 
explosion of the estimated onboard remaining fuel would be capable of 
scattering debris a maximum estimated range of approximately 384 m from 
the landing point and thus spread over a radial area of 0.46 km\2\ as 
an impact area (ManTech 2015). Based on engineering analysis collected 
during a flight anomaly that occurred during a Falcon 9 test at 
SpaceX's Texas Rocket Development Facility, debris could impact 
0.000706

[[Page 18580]]

km\2\ of the total 0.46 km\2\ impact area. Debris impacting an 
individual marine mammal, though highly unlikely as discussed below, 
would have the potential to cause injury and potential mortality.
    Using a statistical probability analysis for estimating direct air 
strike impact developed by the U.S. Navy (Navy 2014), the probability 
of impact of debris with a marine mammal (P) can be estimated for 
individual marine mammals of each species that may occur in the impact 
footprint area (I) (0.000706 km\2\). For this analysis, SpaceX assumed 
a dynamic scenario with broadside collision, in which the width of the 
impact footprint is enhanced by a factor of five (5) to reflect forward 
momentum created by an explosion (Navy 2014). Forward momentum 
typically accounts for five object lengths, thus the applied factor of 
five (5) area (Navy 2014).
    The probability of impact with a single animal (P) is calculated as 
the likelihood that an animal footprint area (A, defined as the adult 
length [La] and width [Wa] for each species) intersects the impact 
footprint area (I) within the overall ``testing area'' (R). Note that 
to calculate (P) it is assumed that the animal is in the testing area 
and is at or near the ocean surface, thus the model is overly 
conservative since cetaceans spend the majority of time submerged. For 
the purposes of this model, R was estimated as the maximum range of 
debris spread as a result of the First Stage explosion at the landing 
location (0.46 km\2\). The probability impact with a single animal (P) 
depends on the degree of overlap of A and I. To calculate this area of 
overlap (Atot), a buffer distance is added around A that is equal to 
one-half of the impact area (0.5*I). This buffer accounts for an impact 
with the center of the object anywhere within the combined area of 
overlap (Atot) would result in an impact with the animal. Atot is then 
calculated as (La + 2*Wi)*(Wa + (1 + 
5)*Li), where Wi and Li are the length and width of the 
impact area (I). We assumed that Wa = Wi = square root of I. The single 
animal impact probability (P) for each species is then calculated as 
the ratio of total area (Atot) to testing area (R): P = Atot/R. This 
single animal impact probability (P) is then multiplied by the number 
of animals expected in the testing area (N = density * R) to estimate 
the probability of impacting an individual for each species per event 
(T).
    SpaceX proposes to conduct up to six contingency offshore landings 
per year, which may result in between zero and six explosions of the 
First Stage annually (as recovery actions continue, SpaceX expects to 
assess each incident, refine methodology and ultimately reduce the risk 
or explosion for the purpose of First Stage recovery and re-use). In 
the model presented in the IHA application, SpaceX assumed that the 
maximum of six events per year would result in an explosion. This is a 
conservative estimate, since the actual number of contingency landing 
events resulting in the First Stage explosion may be less than six. In 
addition, the model conservatively utilized the highest estimated at-
sea individual densities for each species within the geographic area of 
potential impact. Please see Table 6-1 of the IHA application for 
results of the debris strike analysis.
    Even with the intentionally conservative estimates of parameters 
and assumptions in the model as described above, the results indicate 
that it is highly unlikely that debris would strike any individual of 
any marine mammal species, including cetaceans and pinnipeds. For all 
34 marine mammal species that occur in the project area, including 
pinnipeds and cetaceans, the maximum probability of debris strike, for 
a single debris impact event, was 0.0222 for California sea lion (see 
Table 6-1 in the IHA application). The modeled probabilities are 
sufficiently low as to be considered discountable. Therefore, we have 
concluded that the likelihood of take of marine mammals from debris 
strike following the explosion of the Falcon 9 First Stage is 
negligible. As such, debris strike is not analyzed further in this 
proposed authorization as a potential stressor to marine mammals.

Floating Debris

    As described above, in the event of an unsuccessful landing attempt 
at the contingency landing location, the Falcon 9 First Stage would 
explode upon impact with the barge. SpaceX has experience performing 
recovery operations after water and unsuccessful barge landings for 
previous Falcon 9 First Stage landing attempts. This experience, in 
addition to the debris catalog that identifies all floating debris, has 
revealed that approximately 25 pieces of debris remain floating after 
an unsuccessful barge landing. The surface area potentially impacted 
with debris would be less than 0.46 km\2\, and the vast majority of 
debris would be recovered. All other debris is expected to sink to the 
bottom of the ocean.
    The approximately 25 pieces of debris expected to be floating after 
an unsuccessful barge landing are primarily made up of Carbon Over 
Pressure Vessels (COPVs), the LOX fill line, and carbon fiber 
constructed landing legs. SpaceX has performed successful recovery of 
all of these floating items during previous landing attempts. An 
unsuccessful barge landing would result in a very small debris field, 
making recovery of debris relatively straightforward and efficient. All 
debris recovered offshore would be transported back to Long Beach 
Harbor.
    Since the area impacted by debris is very small, the likelihood of 
adverse effects to marine mammals is very low. Denser debris that would 
not float on the surface is anticipated to sink relatively quickly and 
is composed of inert materials which would not affect water quality or 
bottom substrate potentially used by marine mammals. The rate of 
deposition would vary with the type of debris; however, none of the 
debris is so dense or large that benthic habitat would be degraded. 
Also, the area that would be impacted per event by sinking debris is 
only a maximum of 0.17 acres (0.000706 km\2\), a relatively small 
portion of the total 0.46 km\2\ potential impact area, based on a 
maximum range of 384 m that a piece of debris would travel following an 
explosion.
    We have determined that the likelihood of debris from an 
unsuccessful barge landing that enters the ocean environment 
approximately 50 km offshore of VAFB resulting in the incidental take 
of a marine mammal to be so small as to be discountable. Therefore the 
potential effects of floating debris on marine mammals as a result of 
the proposed activities are not considered further in this proposed 
authorization.

Spilled Rocket Propellant

    As described above, in the event of an unsuccessful landing attempt 
at the contingency landing location, the Falcon 9 First Stage would 
explode upon impact with the barge. At most, the First Stage would 
contain 400 gallons of rocket propellant (RP-1 or ``fuel'') on board. 
In the event of an unsuccessful barge landing, most of this fuel would 
be consumed during the subsequent explosion. Residual fuel after the 
explosion (estimated to be between 50 and 150 gallons) would be 
released into the ocean. Final volumes of fuel remaining in the First 
Stage upon impact may vary, but are anticipated to be below this high 
range estimate. The fuel used by the First Stage, RP-1, is a Type 1 
``Very Light Oil'', which is characterized as having low viscosity, low 
specific gravity, and is highly volatile. Clean-up following a spill of 
very light oil is usually not possible, particularly with such a small 
quantity

[[Page 18581]]

of oil that would enter the ocean in the event of an unsuccessful barge 
landing (U.S. Fish and Wildlife Service 1998). Therefore, SpaceX would 
not attempt to boom or recover RP-1 fuel from the ocean.
    In relatively high concentrations, exposure to very light oils can 
have a range of effects to marine mammals including skin and eye 
irritation, increased susceptibility to infection, respiratory 
irritation, gastrointestinal inflammation, ulcers, bleeding, diarrhea, 
damage to organs, immune suppression, reproductive failure, and death. 
The effects of exposure primarily depend on the route (internal versus 
external) and amount (volume and time) of exposure. Although the U.S. 
Environmental Protection Agency has established exposure levels for 
kerosene and jet fuel (RP-1 is a type of kerosene) for toxicity in 
mammals and the environment (U.S. Environmental Protection Agency 
2011), in reality it is difficult to predict exposure levels, even with 
a known amount of fuel released. This is because exposure level is 
dependent not only on the amount of fuel in the spill area, but also on 
unpredictable factors, including the behavior of the animal and the 
amount of fuel it contacts, ingests, or inhales.
    However, precluding these factors is the overall risk of a marine 
mammal being within the fuel spill area before the RP-1 dissipates. 
This risk depends primarily on how quickly RP-1 dissipates in the 
environment and the area affected by the spill. Since RP-1 is lighter 
than water and almost completely immiscible (i.e. very little will 
dissolve into the water column), RP-1 would stay on top of the water's 
surface. Due to its low viscosity, it would rapidly spread into a very 
thin layer (several hundred nanometers) on the surface of water and 
would continue to spread as a function of sea surface, wind, current, 
and wave conditions. This spreading rapidly reduces the concentration 
of RP-1 on the water surface at any one location and exposes more 
surface area of the fuel to the atmosphere, thus increasing the amount 
of RP-1 that is able to evaporate.
    RP-1 is highly volatile and evaporates rapidly when exposed to the 
air (U.S. Fish and Wildlife Service 1998). The evaporation rate for jet 
fuel (a kerosene similar to RP-1) on water, can be determined by the 
following equation from Fingas (2013): %EV = (0.59 + 0.13T)/t, where 
%EV is the percent of mass evaporated within a given time in minutes 
(t) at a given temperature in [deg]C (T). Using an assumed air 
temperature of 50 [deg]F (10 [deg]C), the percent of mass evaporated 
versus time can be determined (see Figure 14 in the IHA application). 
Although it would require one to two days for the RP-1 to completely 
dissipate, over 90 percent of its mass would evaporate within the first 
seven minutes and 99 percent of its mass would evaporate within the 
first hour (see Figure 14 in the IHA application). In the event of 
adverse ocean conditions (e.g., large swells, large waves) and weather 
conditions (e.g., fog, rain, high winds) RP[hyphen]1 would be 
volatilized more rapidly due to increased agitation and thus dissipate 
even more quickly and further reduce the likelihood of exposure.
    Since RP-1 would remain on the surface of the water, in order for a 
marine mammal to be directly exposed to RP-1, it would have to surface 
within the spill area very soon after the spill occurred (on the order 
of minutes). Given the relatively small volume of RP-1 that would be 
spilled (50 to 150 gallons), the exposure area would be relatively 
small and thus it would be unlikely that a marine mammal would be 
within the exposure area. Based on the thinness of the layer of RP-1 on 
the water surface, spreading on the surface (thus rapidly reducing 
concentration), and rapid evaporation (further reducing concentration), 
a marine mammal would need to be at the surface within the layer of RP-
1 and be exposed to a toxic level within a very short period of time 
(minutes) after the spill to be affected. Similarly, since RP-1 would 
be a very thin, rapidly evaporating layer on the water's surface, we do 
not expect that fish or other prey species would be negatively impacted 
to any significant degree.
    We therefore have determined that the likelihood that spilled RP-1, 
as a result of an unsuccessful barge landing that enters the ocean 
environment approximately 50 km from shore, would have an effect on 
marine mammal species is so low as to be discountable. Therefore the 
potential effects of spilled rocket propellant are not considered 
further in this proposed authorization.

Visual Stimuli

    Visual disturbances resulting from Falcon 9 First Stage landings 
have the potential to cause pinnipeds to lift their heads, move towards 
the water, or enter the water. Pinnipeds hauled out at VAFB would 
potentially be able to see the Falcon 9 First Stage landing at SLC-4W. 
However, SpaceX has determined that the trajectory of the return flight 
includes a nearly vertical descent to the SLC-4W landing pad (see 
Figure 1-4 in the IHA application) and the contingency landing location 
(see Figure 1-5 in the IHA application). As a result, there would be no 
significant visual disturbance expected as the descending Falcon 9 
First Stage would either be shielded by coastal bluffs (for a SLC-4W 
landing) or too far away to cause significant stimuli (in the case of a 
barge landing). Further, the visual stimulus of the Falcon 9 First 
Stage would not be coupled with the sonic boom, since the First Stage 
will be at significant altitude when the overpressure is produced 
(described further below), further decreasing the likelihood of a 
behavioral response. Therefore we have determined that the possibility 
of marine mammal harassment from visual stimuli associated with the 
proposed activities is so low as to be considered discountable. 
Therefore visual stimuli associated with the proposed activities are 
not considered further in this proposed authorization.

Acoustic Stimuli

    In the following discussion, we provide general background 
information on sound and marine mammal hearing before considering 
potential effects to marine mammals from sound produced by the proposed 
activities.

Description of Sound Sources

    Acoustic sources associated with SpaceX's proposed activities are 
expected to include: sonic booms; Falcon 9 First Stage landings; and 
potential explosions as a result of unsuccessful Falcon 9 First Stage 
landing attempts at the contingency landing location. Sounds produced 
by the proposed activities may be impulsive, due to sonic boom effects 
and possible explosions, and non-pulse (but short-duration) noise, due 
to combustion effects of the Falcon 9 First Stage.
    Pulsed sound sources (e.g., sonic booms, explosions, gunshots, 
impact pile driving) produce signals that are brief (typically 
considered to be less than one second), broadband, atonal transients 
(ANSI, 1986; Harris, 1998; NIOSH, 1998; ISO, 2003; ANSI, 2005) and 
occur either as isolated events or repeated in some succession. Pulsed 
sounds are all characterized by a relatively rapid rise from ambient 
pressure to a maximal pressure value followed by a rapid decay period 
that may include a period of diminishing, oscillating maximal and 
minimal pressures, and generally have an increased capacity to induce 
physical injury as compared with sounds that lack these features.
    Non-pulsed sounds can be tonal, narrowband, or broadband, brief or 
prolonged, and may be either continuous or non-continuous (ANSI,

[[Page 18582]]

1995; NIOSH, 1998). Some of these non-pulsed sounds can be transient 
signals of short duration but without the essential properties of 
pulses (e.g., rapid rise time). Examples of non-pulsed sounds include 
those produced by rocket launches and landings, vessels, aircraft, 
machinery operations such as drilling or dredging, and vibratory pile 
driving. The duration of such sounds, as received at a distance, can be 
greatly extended in a highly reverberant environment.
    Sound travels in waves, the basic components of which are 
frequency, wavelength, velocity, and amplitude. Frequency is the number 
of pressure waves that pass by a reference point per unit of time and 
is measured in hertz (Hz) or cycles per second. Wavelength is the 
distance between two peaks of a sound wave; lower frequency sounds have 
longer wavelengths than higher frequency sounds and attenuate 
(decrease) more rapidly in shallower water. Amplitude is the height of 
the sound pressure wave or the `loudness' of a sound and is typically 
measured using the decibel (dB) scale. A dB is the ratio between a 
measured pressure (with sound) and a reference pressure (sound at a 
constant pressure, established by scientific standards). It is a 
logarithmic unit that accounts for large variations in amplitude; 
therefore, relatively small changes in dB ratings correspond to large 
changes in sound pressure. When referring to sound pressure levels 
(SPLs; the sound force per unit area), sound is referenced in the 
context of underwater sound pressure to 1 microPascal ([mu]Pa). One 
pascal is the pressure resulting from a force of one newton exerted 
over an area of one square meter. The source level (SL) represents the 
sound level at a distance of 1 m from the source (referenced to 1 
[mu]Pa). The received level is the sound level at the listener's 
position. Note that all underwater sound levels in this document are 
referenced to a pressure of 1 [mu]Pa and all airborne sound levels in 
this document are referenced to a pressure of 20 [mu]Pa.
    Root mean square (rms) is the quadratic mean sound pressure over 
the duration of an impulse, and is calculated by squaring all of the 
sound amplitudes, averaging the squares, and then taking the square 
root of the average (Urick, 1983). Rms accounts for both positive and 
negative values; squaring the pressures makes all values positive so 
that they may be accounted for in the summation of pressure levels 
(Hastings and Popper, 2005). This measurement is often used in the 
context of discussing behavioral effects, in part because behavioral 
effects, which often result from auditory cues, may be better expressed 
through averaged units than by peak pressures.

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals, 
and exposure to sound can have deleterious effects. To appropriately 
assess these potential effects, it is necessary to understand the 
frequency ranges marine mammals are able to hear. Current data indicate 
that 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) recommended 
that marine mammals be divided into functional hearing groups based on 
measured or estimated hearing ranges on the basis of available 
behavioral data, audiograms derived using auditory evoked potential 
techniques, anatomical modeling, and other data. The lower and/or upper 
frequencies for some of these functional hearing groups have been 
modified from those designated by Southall et al. (2007). The 
functional groups and the associated frequencies are indicated below 
(note that these frequency ranges do not necessarily correspond to the 
range of best hearing, which varies by species):
     Low-frequency cetaceans (mysticetes): functional hearing 
is estimated to occur between approximately 7 Hz and 25 kHz (extended 
from 22 kHz; Watkins, 1986; Au et al., 2006; Lucifredi and Stein, 2007; 
Ketten and Mountain, 2009; Tubelli et al., 2012);
     Mid-frequency cetaceans (larger toothed whales, beaked 
whales, and most delphinids): Functional hearing is estimated to occur 
between approximately 150 Hz and 160 kHz;
     High-frequency cetaceans (porpoises, river dolphins, and 
members of the genera Kogia and Cephalorhynchus; now considered to 
include two members of the genus Lagenorhynchus on the basis of recent 
echolocation data and genetic data (May-Collado and Agnarsson, 2006; 
Kyhn et al. 2009, 2010; Tougaard et al. 2010): Functional hearing is 
estimated to occur between approximately 200 Hz and 180 kHz; and
     Pinnipeds: Functional hearing for pinnipeds underwater is 
estimated to occur between approximately 75 Hz to 100 kHz for Phocidae 
(true seals) and between 100 Hz and 48 kHz for Otariidae (eared seals), 
with the greatest sensitivity between approximately 700 Hz and 20 kHz. 
Functional hearing for pinnipeds in air is estimated to occur between 
75 Hz and 30 kHz. 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 
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth et al., 
2013).

Acoustic Effects on Marine Mammals

    The effects of sounds from the proposed activities might result in 
one or more of the following: Temporary or permanent hearing 
impairment, non-auditory physical or physiological effects, behavioral 
disturbance, and masking (Richardson et al., 1995; Gordon et al., 2004; 
Nowacek et al., 2007; Southall et al., 2007). The effects of sounds on 
marine mammals are dependent on several factors, including the species, 
size, behavior (feeding, nursing, resting, etc.), and depth (if 
underwater) of the animal; the intensity and duration of the sound; and 
the sound propagation properties of the environment.
    Impacts to marine species can result from physiological and 
behavioral responses to both the type and strength of the acoustic 
signature (Viada et al., 2008). The type and severity of behavioral 
impacts are more difficult to define due to limited studies addressing 
the behavioral effects of sounds on marine mammals. Potential effects 
from impulsive sound sources can range in severity from effects such as 
behavioral disturbance or tactile perception to physical discomfort, 
slight injury of the internal organs and the auditory system, or 
mortality (Yelverton et al., 1973).
    Hearing Impairment and Other Physical Effects--Marine mammals 
exposed to high intensity sound repeatedly or for prolonged periods can 
experience hearing threshold shift (TS), which is the loss of hearing 
sensitivity at certain frequency ranges (Kastak et al., 1999; Schlundt 
et al., 2000; Finneran et al., 2002, 2005). TS can be permanent (PTS), 
in which case the loss of hearing sensitivity is not recoverable, or 
temporary (TTS), in which case the animal's hearing threshold would 
recover over time (Southall et al., 2007). Marine mammals depend on 
acoustic cues for vital biological functions, (e.g., orientation, 
communication, finding prey, avoiding predators); thus, TTS may result 
in reduced fitness in survival and reproduction. However, this depends 
on the frequency and duration of TTS, as well as the biological context 
in which it occurs. TTS of limited duration, occurring in a frequency 
range that does not coincide with that used for recognition of 
important acoustic cues, would have little to no effect on an

[[Page 18583]]

animal's fitness. Repeated sound exposure that leads to TTS could cause 
PTS. PTS constitutes injury, but TTS does not (Southall et al., 2007). 
The following subsections discuss TTS, PTS, and non-auditory physical 
effects in more detail.
    Temporary Threshold Shift--TTS is the mildest form of hearing 
impairment that can occur during exposure to a strong sound (Kryter, 
1985). While experiencing TTS, the hearing threshold rises, and a sound 
must be stronger in order to be heard. In terrestrial mammals, TTS can 
last from minutes or hours to days (in cases of strong TTS). For sound 
exposures at or somewhat above the TTS threshold, hearing sensitivity 
in both terrestrial and marine mammals recovers rapidly after exposure 
to the sound ends. Available data on TTS in marine mammals are 
summarized in Southall et al. (2007).
    Permanent Threshold Shift--When PTS occurs, there is physical 
damage to the sound receptors in the ear. In severe cases, there can be 
total or partial deafness, while in other cases the animal has an 
impaired ability to hear sounds in specific frequency ranges (Kryter, 
1985). There is no specific evidence that exposure to pulses of sound 
can cause PTS in any marine mammal. However, given the possibility that 
mammals close to a sound source might incur TTS, there has been further 
speculation about the possibility that some individuals might incur 
PTS. Single or occasional occurrences of mild TTS are not indicative of 
permanent auditory damage, but repeated or (in some cases) single 
exposures to a level well above that causing TTS onset might elicit 
PTS.
    Relationships between TTS and PTS thresholds have not been studied 
in marine mammals but are assumed to be similar to those in humans and 
other terrestrial mammals. PTS might occur at a received sound level at 
least several decibels above that inducing mild TTS if the animal were 
exposed to strong sound pulses with rapid rise time. Based on data from 
terrestrial mammals, a precautionary assumption is that the PTS 
threshold for impulse sounds is at least 6 dB higher than the TTS 
threshold on a peak-pressure basis and probably greater than 6 dB 
(Southall et al., 2007). On an SEL basis, Southall et al. (2007) 
estimated that received levels would need to exceed the TTS threshold 
by at least 15 dB for there to be risk of PTS. Thus, for cetaceans, 
Southall et al. (2007) estimate that the PTS threshold might be an M-
weighted SEL (for the sequence of received pulses) of approximately 198 
dB re 1 [mu]Pa\2\-s (15 dB higher than the TTS threshold for an 
impulse). Given the higher level of sound necessary to cause PTS as 
compared with TTS, it is considerably less likely that PTS could occur.
    Captive bottlenose dolphins and beluga whales exhibited changes in 
behavior when exposed to strong pulsed sounds (Finneran et al., 2000, 
2002, 2005). The animals tolerated high received levels of sound before 
exhibiting aversive behaviors. Experiments on a beluga whale showed 
that exposure to a single watergun impulse at a received level of 207 
kPa (30 psi) p-p, which is equivalent to 228 dB p-p, resulted in a 7 
and 6 dB TTS in the beluga whale at 0.4 and 30 kHz, respectively. 
Thresholds returned to within 2 dB of the pre-exposure level within 
four minutes of the exposure (Finneran et al., 2002). In order for 
marine mammals to experience TTS or PTS, the animals must be close 
enough to be exposed to high intensity sound levels for a prolonged 
period of time. The likelihood of PTS or TTS resulting from exposure to 
the proposed activities is considered discountable due to the short 
duration of the sounds generated by the proposed activities and the 
data available on marine mammal responses to the stressors associated 
with the proposed activities, which indicate that PTS and TTS are not 
likely (as described below).
    Non-auditory Physiological Effects--Non-auditory physiological 
effects or injuries that theoretically might occur in marine mammals 
exposed to intense sound include stress, neurological effects, bubble 
formation, resonance effects, and other types of organ or tissue damage 
(Cox et al., 2006; Southall et al., 2007). Studies examining such 
effects are limited and many of these impacts result from exposure to 
underwater sound and therefore are not relevant to the proposed 
activities. In general, little is known about the potential for sonic 
booms to cause non-auditory physical effects in marine mammals. The 
available data do not allow identification of a specific exposure level 
above which non-auditory effects can be expected or any meaningful 
quantitative predictions of the numbers (if any) of marine mammals that 
might be affected in those ways. The likelihood of non-auditory 
physiological effects resulting from exposure to the proposed 
activities is considered discountable due to data available on marine 
mammal responses to the stressors associated with the proposed 
activities (as described below).

Disturbance Reactions

    Disturbance includes a variety of effects, including subtle changes 
in behavior, more conspicuous changes in activities, and displacement. 
Behavioral responses to sound are highly variable and context-specific 
and reactions, if any, depend on species, state of maturity, 
experience, current activity, reproductive state, auditory sensitivity, 
time of day, and many other factors (Richardson et al., 1995; Wartzok 
et al., 2003; Southall et al., 2007).
    Habituation can occur when an animal's response to a stimulus wanes 
with repeated exposure, usually in the absence of unpleasant associated 
events (Wartzok et al., 2003). Animals are most likely to habituate to 
sounds that are predictable and unvarying. The opposite process is 
sensitization, when an unpleasant experience leads to subsequent 
responses, often in the form of avoidance, at a lower level of 
exposure. Behavioral state may affect the type of response as well. For 
example, animals that are resting may show greater behavioral change in 
response to disturbing sound levels than animals that are highly 
motivated to remain in an area for feeding (Richardson et al., 1995; 
NRC, 2003; Wartzok et al., 2003).
    Controlled experiments with captive marine mammals have shown 
pronounced behavioral reactions, including avoidance of loud underwater 
sound sources (Ridgway et al., 1997; Finneran et al., 2003). Observed 
responses of wild marine mammals to loud pulsed sound sources 
(typically seismic guns or acoustic harassment devices) have been 
varied but often consist of avoidance behavior or other behavioral 
changes suggesting discomfort (Morton and Symonds, 2002; Thorson and 
Reyff, 2006; see also Gordon et al., 2004; Wartzok et al., 2003; 
Nowacek et al., 2007).
    The onset of noise can result in temporary, short term changes in 
an animal's typical behavior and/or avoidance of the affected area. 
These behavioral changes may include (Richardson et al., 1995): 
Reduced/increased vocal activities; changing/cessation of certain 
behavioral activities (such as socializing or feeding); visible startle 
response or aggressive behavior; avoidance of areas where sound sources 
are located; and/or flight responses.
    The biological significance of many of these behavioral 
disturbances is difficult to predict, especially if the detected 
disturbances appear minor. However, the consequences of behavioral 
modification could potentially be biologically significant if the 
change affects growth, survival, or reproduction. The onset of 
behavioral disturbance from anthropogenic sound depends on both 
external factors

[[Page 18584]]

(characteristics of sound sources and their paths) and the specific 
characteristics of the receiving animals (hearing, motivation, 
experience, demography) and is difficult to predict (Southall et al., 
2007).

Auditory Masking

    Natural and artificial sounds can disrupt behavior by masking, or 
interfering with, a marine mammal's ability to hear other sounds. 
Masking occurs when the receipt of a sound is interfered with by 
another coincident sound at similar frequencies and at similar or 
higher levels. Chronic exposure to excessive, though not high-
intensity, sound could cause masking at particular frequencies for 
marine mammals that utilize sound for vital biological functions. 
Masking can interfere with detection of acoustic signals such as 
communication calls, echolocation sounds, and environmental sounds 
important to marine mammals. Therefore, under certain circumstances, 
marine mammals whose acoustical sensors or environment are being 
severely masked could also be impaired from maximizing their 
performance fitness in survival and reproduction. If the coincident 
(masking) sound were man-made, it could be potentially harassing if it 
disrupted hearing-related behavior. It is important to distinguish TTS 
and PTS, which persist after the sound exposure, from masking, which 
occurs during the sound exposure. Because masking (without resulting in 
TS) is not associated with abnormal physiological function, it is not 
considered a physiological effect, but rather a potential behavioral 
effect. The likelihood of masking resulting from exposure to sound from 
the proposed activities is considered discountable due to the short 
duration of the sounds generated by the proposed activities (as 
described below).

Acoustic Effects, Airborne

    Marine mammals that occur in the project area could be exposed to 
airborne sounds associated with Falcon 9 First Stage recovery 
activities, including sonic booms, landing sounds, and potentially 
explosions, that have the potential to cause harassment, depending on 
the animal's distance from the sound. Airborne sound could potentially 
affect pinnipeds that are hauled out. Most likely, airborne sound would 
cause behavioral responses similar to those discussed above in relation 
to underwater sound. For instance, anthropogenic sound could cause 
hauled out pinnipeds to exhibit changes in their normal behavior, such 
as reduction in vocalizations, or cause them to temporarily abandon 
their habitat and move further from the source. Hauled out pinnipeds 
may flush into the water, which can potentially result in pup 
abandonment or trampling of pups. Studies by Blackwell et al. (2004) 
and Moulton et al. (2005) indicate a tolerance or lack of response to 
unweighted airborne sounds as high as 112 dB peak and 96 dB rms.

Acoustic Effects of the Proposed Activities

    As described above, the sound sources associated with the proposed 
activities that have the potential to result in harassment of marine 
mammals include: Sonic booms; landing noise; and potential explosions 
associated with unsuccessful barge landing attempts. We describe each 
of these sources separately and in more detail below.

Explosion Resulting From Unsuccessful Barge Landing Attempt

    In the event of an unsuccessful barge landing, the Falcon 9 First 
Stage would likely explode. Noise resulting from such an explosion 
would introduce impulsive sound into both the air and the water. This 
sound would be in the audible range of most marine mammals, even if the 
duration is expected to be very short (likely less than a second). The 
spacing of the landing attempts (no more than six over one year) would 
likely reduce the potential for long-term auditory masking. However, 
because of its intensity, the direct sound from an explosion has the 
potential to result in behavioral or physiological effects in marine 
mammals. The intensity of the explosion would likely vary depending on 
the amount of fuel remaining in the Falcon 9 First Stage, but for our 
analysis we assumed a worst-case scenario: That the largest possible 
amount of fuel would be left in the First Stage upon impact.
    Noise resulting from an unsuccessful barge landing would be 
expected to generate an in-air impulsive sound pressure level up to 180 
dB rms re 20[mu]Pa (ManTech 2015). NMFS's current acoustic criteria for 
in-air acoustic impacts assumes Level B harassment of non-harbor seal 
pinnipeds occurs at 100 dB rms re 20[mu]Pa, with Level B harassment of 
harbor seals occurring at 90 dB rms re 20[mu]Pa (Table 2). No threshold 
for Level A harassment for in-air noise has been established. To 
determine whether harassment of pinnipeds was likely to occur as a 
result of in-air noise from explosion of the Falcon 9 First Stage at 
the contingency landing location, SpaceX performed modeling to 
determine the distance at which the sound level from such an explosion 
would attenuate to 90 dB rms re 20[micro]Pa (the lowest NMFS threshold 
for pinniped harassment, as described above).

      Table 2--NMFS Criteria for Acoustic Impacts to Marine Mammals
------------------------------------------------------------------------
           Criterion             Criterion definition       Threshold
------------------------------------------------------------------------
In-Water Acoustic Thresholds
------------------------------------------------------------------------
Level A.......................  PTS (injury)            190 dBrms for
                                 conservatively based    pinnipeds
                                 on TTS.                180 dBrms for
                                                         cetaceans.
Level B.......................  Behavioral disruption   160 dBrms.
                                 for impulsive noise.
Level B.......................  Behavioral disruption   120 dBrms.
                                 for non-pulse noise.
------------------------------------------------------------------------
In-Air Acoustic Thresholds
------------------------------------------------------------------------
Level A.......................  PTS (injury)            None
                                 conservatively based    established.
                                 on TTS.
Level B.......................  Behavioral disruption   90 dBrms.
                                 for harbor seals.
Level B.......................  Behavioral disruption   100 dBrms.
                                 for non-harbor seal
                                 pinnipeds.
------------------------------------------------------------------------


[[Page 18585]]

    The explosion would generate an in-air impulsive noise that would 
propagate in a radial fashion away from the barge. Based on the size of 
the anticipated explosion, Sadovsky equations were used to calculate 
peak received pressures (received levels are a function of charge 
weight and distance from source) at sound pressure contour lines. Since 
the sound pressure levels were peak levels, the approximate RMS values 
were estimated by converting peak to RMS (peak pressure value * 0.707). 
Then, these values were converted into dB re 20 [mu]Pa to determine 
distances to defined contour levels and in-air acoustic threshold 
levels for marine mammal harassment (see Figure 2-7 in the IHA 
application). To generate realistic sound pressure contour lines, 
atmospheric attenuation was included in the model. Calculations for 
atmospheric attenuation included the following assumptions: The 
explosion was assumed to be 250 hertz or less, relative humidity was 
assumed to be 30 percent and air temperature was assumed to be 50 
[deg]F (10 [deg]C). This model does not take into account additional 
factors that would be expected to attenuate the blast wave further, 
including: Sea surface roughness, changes in atmospheric pressure, 
frontal systems, precipitation, clouds, and degradation when 
encountering other sound pressure waves. Thus, the area of exposure is 
likely to be conservative. Results indicated that an impulsive in-air 
noise resulting from a Falcon 9 First Stage explosion at the barge 
would attenuate to 90 dB rms re 20[micro]Pa at a radius of 26.5 km from 
the contingency landing location (ManTech 2015). There are no pinniped 
haulouts located within this area (See Figure 2-7 in the IHA 
application); therefore in-air noise generated by an explosion of the 
Falcon 9 First Stage during an unsuccessful barge landing would not 
result in Level B harassment of marine mammals.
    Explosions near the water's surface can introduce loud, impulsive, 
broadband sounds into the marine environment. These sounds can 
potentially be within the audible range of most marine mammals, though 
the duration of individual sounds is very short. The direct sound from 
an explosion would last less than a second. Furthermore, events are 
dispersed in time, with maximum of six barge landing attempts occurring 
within the time period that the proposed IHA would be valid. If an 
explosion occurred on the barge, as in the case of an unsuccessful 
barge landing, some amount of the explosive energy would be transferred 
through the ship's structure and would enter the water and propagate 
away from the ship. There is very little published literature on the 
ratio of explosive energy that is absorbed by a ship's hull versus the 
amount of energy that is transferred through the ship into the water. 
However, based on the best available information, we have determined 
that exceptionally little of the acoustic energy from the explosion 
would transmit into the water (Yagla and Stiegler 2003). An explosion 
on the barge would create an in-air blast that propagates away in all 
directions, including toward the water's surface; however the barge's 
deck would act as a barrier that would attenuate the energy directed 
downward toward the water (Yagla and Stiegler 2003). Most sound enters 
the water in a narrow cone beneath the sound source (within 13 degrees 
of vertical). Since the explosion would occur on the barge, most of 
this sound would be reflected by the barge's surface, and sound waves 
would approach the water's surface at angles higher than 13 degrees, 
minimizing transmission into the ocean. An explosion on the barge would 
also send energy through the barge's structure, into the water, and 
away from the barge. This effect was investigated in conjunction with 
the measurements described in Yagla and Steigler (2003). The energy 
transmitted through a ship to the water for the firing of a typical 5-
inch round was approximately six percent of that from the air blast 
impinging on the water (Yagla and Stiegler 2003). Therefore, sound 
transmitted from the blast through the hull into the water was a 
minimal component of overall firing noise, and would likewise be 
expected to be a minimal component of an explosion occurring on the 
surface of the barge.
    Depending on the amount of fuel remaining in the booster at the 
time of the explosion, the intensity of the explosion would likely 
vary. As indicated above, the explosive equivalence of the First Stage 
with maximum fuel and oxidizer is 503 lb. of TNT. Explosion shock 
theory has proposed specific relationships for the peak pressure and 
time constant in terms of the charge weight and range from the 
detonation position (Pater 1981; Plotkin et al. 2012). For an in-air 
explosion equivalent to 500 lb. of TNT, at 0.5 feet the explosion would 
be approximately 250 dB re 20[mu]Pa. Based on the assumption that the 
structure of the barge would absorb and reflect approximately 94 
percent of this energy, with approximately six percent of the energy 
from the explosion transmitted into the water (Yagla and Stiegler 
2003), the amount of energy that would be transmitted into the water 
would be far less than the lowest threshold for Level B harassment for 
both pinnipeds and cetaceans based on NMFS's current acoustic criteria 
for in-water explosive noise (see Table 3). As a result, the likelihood 
of in-water sound generated by an explosion of the Falcon 9 First Stage 
during an unsuccessful barge landing attempt resulting in take of 
marine mammals is considered so low as to be discountable.

                                      Table 3--NMFS Acoustic Criteria for Impacts to Marine Mammals From Explosives
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                               Level B                                     Level A
                                                ----------------------------------------------------------------------------------------
            Group                   Species       Behavioral (for                                          Gastro-                          Mortality
                                                   >=2 pulses/24          TTS               PTS           intestinal      Lung injury
                                                      hours)                                             tract injury
--------------------------------------------------------------------------------------------------------------------------------------------------------
Low-Frequency Cetaceans......  Mysticetes......  167 dB SEL......  172 dB SEL or     187 dB SEL or     237 dB SPL/104   39.1 M1/3        91.4 M1/3
                                                                    224 dB peak SPL.  230 dB peak SPL.  psi.             (1+[DRm/         (1+[DRm/
                                                                                                                         10.081]1/2 Pa-   10.081]1/2 Pa-
                                                                                                                         sec Where: M =   sec Where: M =
                                                                                                                         mass of the      mass of the
                                                                                                                         animal in kg     animal in kg
                                                                                                                         DRm = depth of   DRm = depth of
                                                                                                                         the receiver     the receiver
                                                                                                                         in meters.       in meters.
Mid-Frequency Cetaceans......  Most delphinids,  167 dB SEL......  172 dB SEL or     187 dB SEL or
                                medium & large                      224 dB peak SPL.  230 dB peak SPL.
                                toothed whales.

[[Page 18586]]

 
High-Frequency Cetaceans.....  Porpoises and     141 dB SEL......  146 dB SEL or     161 dB SEL or
                                Kogia spp.                          195 dB peak SPL.  201 dB peak SPL.
Phocids......................  Elephant &        172 dB SEL......  177 dB SEL or     192 dB SEL or
                                harbor seal.                        212 dB peak SPL.  218 Db peak SPL.
Otariids.....................  Sea lions & fur   195 dB SEL......  200 dB SEL or     215 dB SEL or
                                seals.                              212 Db peak SPL.  218 Db peak SPL.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    As we have determined that neither in-air noise nor underwater 
noise associated with potential explosions from an unsuccessful Falcon 
9 First Stage landing attempt at the contingency landing location would 
result in take of marine mammals, explosions as a result of 
unsuccessful landing attempts at the contingency landing location are 
not considered further in this proposed authorization. The likelihood 
of a Falcon 9 First Stage completely missing the barge during a landing 
attempt, and directly impacting the surface of the water, is considered 
to be so low as to be discountable; therefore this scenario is not 
analyzed in terms of its potential to result in take of marine mammals. 
Likewise, the likelihood of a Falcon 9 First Stage landing failure at 
VAFB, resulting in an explosion of the First Stage on the SLC-4W 
landing pad, is considered to be so low as to be discountable; 
therefore this scenario is not analyzed in terms of its potential to 
result in take of marine mammals.

Landing Noise

    A final engine burn during the landing of the Falcon 9 First Stage, 
lasting approximately 17 seconds, would generate non-pulse in-air noise 
that could potentially result in hauled out pinnipeds alerting, moving 
away from the noise, or flushing into the water. SpaceX determined that 
the landing noise would generate non-pulse in-air noise of between 70 
and 110 dB re 20 [mu]Pa centered on SLC-4W, but affecting an area up to 
22.5 km offshore of VAFB (see Figure 2-5 in the IHA application) 
(ManTech 2015). Engine noise would also be produced during Falcon 9 
First Stage landings at the contingency landing location; the potential 
area of influence for barge landings was estimated by extrapolating the 
landing noise profile from a SLC-4W landing (see Figure 2-5 in the IHA 
application). Engine noise during the barge landing is also expected to 
be between 70 and 110 dB re 20 [mu]Pa non-pulse in-air noise affecting 
a radial area up to 22.5 km around the contingency landing location 
(see Figure 2-6 in the IHA application).
    As described above, NMFS's current acoustic criteria for in-air 
acoustic impacts assumes Level B harassment of non-harbor seal 
pinnipeds occurs at 100 dB rms re 20[mu]Pa, with Level B harassment of 
harbor seals occurring at 90 dB rms re 20[mu]Pa (Table 2). No threshold 
for Level A harassment for in-air noise has been established. Based on 
SpaceX's modeling of the propagation of noise from a Falcon 9 First 
Stage landing, there are no pinniped haulouts within the area modeled 
to be impacted by landing noise at 90 dB or greater, for either a 
landing at VAFB (see Figure 2-5 in the IHA application) or a 
contingency barge landing (see Figure 2-6 in the IHA application) 
(ManTech 2015). Therefore we believe it is unlikely that hauled out 
pinnipeds will be harassed by the noise associated with Falcon 9 First 
Stage landings, either at VAFB or at the contingency landing location. 
The noise associated with Falcon 9 First Stage landings would not be 
expected to have an effect on submerged animals or those that spend a 
considerable amount of time submerged, such as cetaceans. Therefore the 
likelihood of take resulting from noise from a Falcon 9 First Stage 
landing, either at VAFB or at the contingency landing location, is 
considered so low as to be discountable. As such, landing noise is not 
considered further in this proposed authorization.

Sonic Boom

    During descent when the First Stage is supersonic, a sonic boom 
(overpressure of high-energy impulsive sound) would be generated. 
During a landing event at SLC-4W, the sonic boom would be directed at 
the coastal area south of SLC-4W (see Figure 2-1 in the IHA 
application). Acoustic modeling was performed to estimate the area of 
expected impact and overpressure levels that would be created during 
the return flight of the Falcon 9 First Stage (Wyle, Inc. 2015). The 
boom footprint was computed using PCBoom (Plotkin and Grandi 2002; Page 
et al. 2010). The vehicle is a cylinder generally aligned with the 
velocity vector, descending engines first (see Figure 1-3 in the IHA 
application). It was modeled via PCBoom's drag-dominated blunt body 
mode (Tiegerman 1975), which has been validated for entry vehicles 
(Plotkin et al. 2006). Drag is determined by vehicle weight and the 
kinematics of the trajectory. Kinematics include the effect of the 
retro burn. The model results predict that sonic overpressures would 
reach up to 2.0 pounds per square foot (psf) in the immediate area 
around SLC-4W (Figures 2-1 and 2-2) and an overpressure between 1.0 and 
2.0 psf would impact the coastline of VAFB from approximately 8 km 
north of SLC-4 to approximately 18 km southeast of SLC-4W (see Figures 
2-1 and 2-2 in the IHA application). A significantly larger area, 
including the mainland, the Pacific Ocean, and the NCI, would 
experience an overpressure between 0.1 and 1.0 psf (see Figure 2-1 in 
the IHA application). In addition, San Miguel Island and Santa Rosa 
Island may experience an overpressure up to 3.1 psf and the west end of 
Santa Cruz Island may experience an overpressure up to 1.0 psf (see 
Figures 2-1 and 2-3 in the IHA application).
    During a contingency barge landing event, an overpressure would 
also be generated while the first-stage booster is supersonic. The 
overpressure would be directed at the ocean surface no less than 50 km 
off the coast of VAFB. The SLC-4W pad-based landing

[[Page 18587]]

overpressure modeling was roughly extrapolated to show potential noise 
impacts for landing 50 km to the west of VAFB (see Figure 2-4 in the 
IHA application). An overpressure of up to 2.0 psf would impact the 
Pacific Ocean at the contingency landing location approximately 50 km 
offshore of VAFB. San Miguel Island and Santa Rosa Island would 
experience a sonic boom between 0.1 and 0.2 psf. Sonic boom 
overpressures on the mainland would be between 0.2 and 0.4 psf.

Behavioral Responses of Pinnipeds to Sonic Booms

    The USAF has monitored pinniped responses to rocket launches from 
VAFB for nearly 20 years. Though rocket launches are not part of the 
proposed activities (as described above), the acoustic stimuli (sonic 
booms) associated with launches is expected to be substantially similar 
to those expected to occur with Falcon 9 boost-backs and landings; 
therefore, we rely on observational data on responses of pinnipeds to 
sonic booms associated with rocket launches from VAFB in making 
assumptions about expected pinniped responses to sound associated with 
Falcon 9 boost-backs and landings.
    Observed reactions of pinnipeds at the NCI to sonic booms have 
ranged from no response to heads-up alerts, from startle responses to 
some movements on land, and from some movements into the water to 
occasional stampedes (especially involving California sea lions on the 
NCI). We therefore assume sonic booms generated during the return 
flight of the Falcon 9 First Stage may elicit an alerting or other 
short-term behavioral reaction, including flushing into the water if 
hauled out. NMFS considers pinnipeds behaviorally reacting to stimuli 
by flushing into the water, moving more than 1 meter but not into the 
water; becoming alert and moving more than 1 meter; and changing 
direction of current movements as behavioral criteria for take by Level 
B harassment. As such, SpaceX has requested, and we propose to 
authorize, take of small numbers of marine mammals by Level B 
harassment incidental to Falcon 9 boost-backs and landings associated 
with sonic booms.
    Data from launch monitoring by the USAF on the NCI has shown that 
pinniped reactions to sonic booms are correlated with the level of the 
sonic boom. Low energy sonic booms (<1.0 psf) have resulted in little 
to no behavioral responses, including head raising and briefly alerting 
but returning to normal behavior shortly after the stimulus (Table 4). 
More powerful sonic booms have resulted in pinnipeds flushing from 
haulouts. No pinniped mortalities have been associated with sonic 
booms. No sustained decreases in numbers of animals observed at 
haulouts have been observed after the stimulus. Table 4 presents a 
summary of monitoring efforts at the NCI from 1999 to 2011. These data 
show that reactions to sonic booms tend to be insignificant below 1.0 
psf and that, even above 1.0 psf, only a portion of the animals present 
have reacted to the sonic boom. Time-lapse video photography during 
four launch events revealed that harbor seals that reacted to the 
rocket launch noise but did not leave the haul-out were all adults.
    Data from previous monitoring also suggests that for those 
pinnipeds that flush from haulouts in response to sonic booms, the 
amount of time it takes for those animals to begin returning to the 
haulout site, and for numbers of animals to return to pre-launch 
levels, is correlated with sonic boom sound levels. Pinnipeds may begin 
to return to the haul-out site within 2-55 min of the launch 
disturbance, and the haulout site usually returned to pre-launch levels 
within 45-120 min. Monitoring data from launches of the Athena IKONOS 
rocket from VAFB, with ASELs of 107.3 and 107.8 dB recorded at the 
closest haul-out site, showed seals that flushed to the water on 
exposure to the sonic boom began to return to the haul-out 
approximately 16-55 minutes post-launch (Thorson et al., 1999a; 1999b). 
In contrast, in the cases of Atlas rocket launches and several Titan II 
rocket launches with ASELs ranging from 86.7 to 95.7 dB recorded at the 
closest haul-out, seals began to return to the haul-out site within 2-8 
minutes post-launch (Thorson and Francine, 1997; Thorson et al., 2000).
    Monitoring data has consistently shown that reactions among 
pinnipeds vary between species, with harbor seals and California sea 
lions tending to be more sensitive to disturbance than northern 
elephant seals and northern fur seals (Table 4). Because Steller sea 
lions and Guadalupe fur seals occur in the project area relatively 
infrequently, no data has been recorded on their reactions to sonic 
booms. At VAFB, harbor seals generally alert to nearby launch noises, 
with some or all of the animals going into the water. Usually the 
animals haul out again from within minutes to two hours or so of the 
launch, provided rising tides or breakers have not submerged the haul-
out sites. Post-launch surveys often indicate as many or more animals 
hauled out than were present at the time of the launch, unless rising 
tides, breakers or other disturbances are involved (SAIC 2012). When 
launches occurred during high tides at VAFB, no impacts have been 
recorded because virtually all haul-out sites were submerged. At San 
Miguel Island, California sea lions react more strongly to sonic booms 
than most other species. Pups may react more than adults, either 
because they are more easily frightened or because their hearing is 
more acute. Although California sea lions on San Miguel Island tend to 
react to sonic booms, most disturbances are minor and temporary in 
nature (USAF 2013b). Harbor seals also appear to be more sensitive to 
sonic booms than other pinnipeds, often startling and fleeing into the 
water. Northern fur seals often show little or no reaction. Northern 
elephant seals generally exhibit no reaction at all, except perhaps a 
heads-up response or some stirring, especially if sea lions in the same 
area react strongly to the boom. Post-launch monitoring generally 
reveals a return to normal patterns within minutes up to an hour or two 
of each launch, regardless of species (SAIC 2012).
    Table 4 summarizes monitoring efforts at San Miguel Island during 
which acoustic measurements were successfully recorded and during which 
pinnipeds were observed. During more recent launches, night vision 
equipment was used. The table shows only launches during which sonic 
booms were heard and recorded. The table shows that little or no 
reaction from the four species usually occurs when overpressures are 
below 1.0 psf. In general, as described above, elephant seals do not 
react unless other animals around them react strongly or if the sonic 
boom is extremely loud, and northern fur seals seem to react similarly. 
Not enough data exist to draw conclusions about harbor seals, but 
considering their reactions to launch noise at VAFB, it is likely that 
they are also sensitive to sonic booms (SAIC 2012).

[[Page 18588]]



                         Table 4--Pinniped Reactions to Sonic Booms at San Miguel Island
----------------------------------------------------------------------------------------------------------------
                                          Sonic boom
              Launch event               level (psf)           Location            Species & associated reaction
----------------------------------------------------------------------------------------------------------------
Athena II (27 April 1999)..............          1.0  Adams Cove................  Calif. sea lion--866 alerted;
                                                                                   232 flushed into water
                                                                                   northern elephant seal--
                                                                                   alerted but did not flush
                                                                                   northern fur seal--alerted
                                                                                   but did not flush.
Athena II (24 September 1999)..........         0.95  Point Bennett.............  Calif. sea lion--600 alerted;
                                                                                   12 flushed into water
                                                                                   northern elephant seal--
                                                                                   alerted but did not flush
                                                                                   northern fur seal--alerted
                                                                                   but did not flush.
Delta II 20 (November 2000)............          0.4  Point Bennett.............  Calif. sea lion--60 flushed
                                                                                   into water; no reaction from
                                                                                   rest Northern elephant seal--
                                                                                   no reaction.
Atlas II (8 September 2001)............         0.75  Cardwell Point............  Calif. sea lion--no reaction
                                                                                   northern elephant seal--no
                                                                                   reaction harbor seal--2 of 4
                                                                                   flushed into water.
Delta II (11 February 2002)............         0.64  Point Bennett.............  Calif. sea lion--no reaction
                                                                                   northern fur seal--no
                                                                                   reaction northern elephant
                                                                                   seal--no reaction.
Atlas II (2 December 2003).............         0.88  Point Bennett.............  Calif. sea lion--40% alerted;
                                                                                   several flushed to water
                                                                                   northern elephant seal--no
                                                                                   reaction.
Delta II (15 July 2004)................         1.34  Adams Cove................  Calif. sea lion--10% alerted.
Atlas V (13 March 2008)................         1.24  Cardwell Point............  northern elephant seal--no
                                                                                   reaction.
Delta II (5 May 2009)..................         0.76  West of Judith Rock.......  Calif. sea lion--no reaction.
Atlas V (14 April 2011)................         1.01  Cuyler Harbor.............  northern elephant seal--no
                                                                                   reaction.
Atlas V (3 April 2014).................         0.74  Cardwell Point............  harbor seal--1 of ~25 flushed
                                                                                   into water; no reaction from
                                                                                   others.
Atlas V (12 December 2014).............         1.16  Point Bennett.............  Calif. sea lion--5 of ~225
                                                                                   alerted; none flushed.
----------------------------------------------------------------------------------------------------------------

Physiological Responses to Sonic Booms

    To determine if harbor seals experience changes in their hearing 
sensitivity as a result of sounds associated with rocket launches 
(including sonic booms), Auditory Brainstem Response (ABR) testing was 
conducted on 14 harbor seals following four launches of the Titan IV 
rocket, one launch of the Taurus rocket, and two launches of the Delta 
IV rocket from VAFB, in accordance with NMFS scientific research 
permits. ABR tests have not yet been performed following Falcon 9 
rocket landings nor launches, however results of ABR tests that 
followed launches of other rockets from VAFB are nonetheless 
informative as the sound source (sonic boom) is expected to be the same 
as that associated with the activities proposed by SpaceX.
    Following standard ABR testing protocol, the ABR was measured from 
one ear of each seal using sterile, sub-dermal, stainless steel 
electrodes. A conventional electrode array was used, and low-level 
white noise was presented to the non-tested ear to reduce any 
electrical potentials generated by the non-tested ear. A computer was 
used to produce the click and an 8 kilohertz (kHz) tone burst stimuli, 
through standard audiometric headphones. Over 1,000 ABR waveforms were 
collected and averaged per trial. Initially the stimuli were presented 
at SPLs loud enough to obtain a clean reliable waveform, and then 
decreased in 10 dB steps until the response was no longer reliably 
observed. Once response was no longer reliably observed, the stimuli 
were then increased in 10 dB steps to the original SPL. By obtaining 
two ABR waveforms at each SPL, it was possible to quantify the 
variability in the measurements.
    Good replicable responses were measured from most of the seals, 
with waveforms following the expected pattern of an increase in latency 
and decrease in amplitude of the peaks, as the stimulus level was 
lowered. Detailed analysis of the changes in waveform latency and 
waveform replication of the ABR measurements for the 14 seals showed no 
detectable changes in the seals' hearing sensitivity as a result of 
exposure to the launch noise. The delayed start (1.75 to 3.5 hours 
after the launches) for ABR testing allows for the possibility that the 
seals may have recovered from a TTS before testing began. However, it 
can be said with confidence that the post-launch tested animals did not 
have permanent hearing changes due to exposure to the launch noise from 
the sonic booms associated with launches of the rockets from VAFB (SAIC 
2013).
    NMFS also notes that stress from long-term cumulative sound 
exposures can result in physiological effects on reproduction, 
metabolism, and general health, or on the animals' resistance to 
disease. However, this is not likely to occur as a result of the 
proposed activities because of the infrequent nature and short duration 
of the noise (up to six sonic booms annually). Research indicates that 
population levels at these haul-out sites have remained constant in 
recent years (with decreases only noted in some areas because of the 
increased presence of coyotes), giving support to this conclusion.

Anticipated Effects on Marine Mammal Habitat

    Impacts on marine mammal habitat are part of the consideration in 
making a finding of negligible impact on the species and stocks of 
marine mammals. Habitat includes rookeries, mating grounds, feeding 
areas, and areas of similar significance. We do not anticipate that the 
proposed activities would result in any temporary or permanent effects 
on the habitats used by the marine mammals in the proposed area, 
including the food sources they use (i.e. fish and invertebrates). 
Behavioral disturbance caused by in-air acoustic stimuli may result in 
marine mammals temporarily moving away from or avoiding the exposure 
area but are not expected to have long term impacts, as supported by 
over two decades of launch monitoring studies on the Northern Channel 
Islands by the U.S. Air Force (MMCG and SAIC 2012).

Effects on Potential Prey and Foraging Habitat

    The proposed activities would not result in in-water acoustic 
stimuli that would cause significant injury or mortality to prey 
species and would not create barriers to movement for marine mammal 
prey. In the event of an unsuccessful barge landing and a resulting 
explosion of the Falcon 9 First Stage, up to 25 pieces of debris would 
likely remain floating (see Section 6.5.1 in the IHA application for 
further details). SpaceX would recover all floating debris. Denser 
debris that

[[Page 18589]]

would not float on the surface is anticipated to sink relatively 
quickly and would be composed of inert materials. The area of benthic 
habitat impacted by falling debris would be very small (approximately 
0.000706 km\2\) (ManTech 2015) and all debris that would sink are 
composed of inert materials that would not affect water quality or 
bottom substrate potentially used by marine mammals. None of the debris 
would be so dense or large that benthic habitat would be degraded. As a 
result, debris from an unsuccessful barge landing that enters the ocean 
environment approximately 50 km offshore of VAFB would not have a 
significant effect on marine mammal habitat.
    In summary, since the acoustic impacts associated with the proposed 
activities are of short duration and infrequent (up to six events 
annually), the associated behavioral responses in marine mammals are 
expected to be temporary. Therefore, the proposed activities are 
unlikely to result in long term or permanent avoidance of the exposure 
areas or loss of habitat. The proposed activities are also not expected 
to result in any reduction in foraging habitat or adverse impacts to 
marine mammal prey. Thus, any impacts to marine mammal habitat are not 
expected to cause significant or long-term consequences for individual 
marine mammals or their populations.

Proposed Mitigation

    In order to issue an IHA under section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to such 
activity, and other means of effecting the least practicable impact on 
such species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of such species or stock for taking for certain 
subsistence uses.
    SpaceX's IHA application contains descriptions of the mitigation 
measures proposed to be implemented during the specified activities in 
order to effect the least practicable adverse impact on the affected 
marine mammal species and stocks and their habitats. The proposed 
mitigation measures include the following:
     Unless constrained by other factors including human safety 
or national security concerns, launches will be scheduled to avoid, 
whenever possible, boost-backs and landings during the harbor seal 
pupping season of March through June.
    We have carefully evaluated SpaceX's proposed mitigation and 
considered their likely effectiveness relative to implementation of 
similar mitigation measures in previously issued incidental take 
authorizations to preliminarily determine whether they are likely to 
affect the least practicable impact on the affected marine mammal 
species and stocks and their habitat. Our evaluation of potential 
measures included consideration of the following factors in relation to 
one another:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure is expected to minimize adverse impacts 
to marine mammals;
    (2) The proven or likely efficacy of the specific measure to 
minimize adverse impacts as planned; and
    (3) The practicability of the measure for applicant implementation.
    Any mitigation measure(s) we prescribe should be able to 
accomplish, have a reasonable likelihood of accomplishing (based on 
current science), or contribute to the accomplishment of one or more of 
the general goals listed below:
    (1) Avoidance or minimization of injury or death of marine mammals 
wherever possible (goals 2, 3, and 4 may contribute to this goal).
    (2) A reduction in the number (total number or number at 
biologically important time or location) of individual marine mammals 
exposed to stimuli expected to result in incidental take (this goal may 
contribute to 1, above, or to reducing takes by behavioral harassment 
only).
    (3) A reduction in the number (total number or number at 
biologically important time or location) of times any individual marine 
mammal would be exposed to stimuli expected to result in incidental 
take (this goal may contribute to 1, above, or to reducing takes by 
behavioral harassment only).
    (4) A reduction in the intensity of exposure to stimuli expected to 
result in incidental take (this goal may contribute to 1, above, or to 
reducing the severity of behavioral harassment only).
    (5) Avoidance or minimization of adverse effects to marine mammal 
habitat, paying particular attention to the prey base, blockage or 
limitation of passage to or from biologically important areas, 
permanent destruction of habitat, or temporary disturbance of habitat 
during a biologically important time.
    (6) For monitoring directly related to mitigation, an increase in 
the probability of detecting marine mammals, thus allowing for more 
effective implementation of the mitigation.
    Based on our evaluation of SpaceX's proposed measures, we have 
preliminarily determined that the proposed mitigation measures provide 
the means of effecting the least practicable impact on marine mammal 
species or stocks and their habitat. While we have determined 
preliminarily that the proposed mitigation measures presented in this 
document will affect the least practicable adverse impact on the 
affected species or stocks and their habitat, we will consider all 
public comments to help inform our final decision.

Proposed Monitoring and Reporting

    In order to issue an IHA for an activity, section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth ``requirements pertaining to 
the monitoring and reporting of such taking.'' The MMPA implementing 
regulations at 50 CFR 216.104(a)(13) indicate that requests for 
incidental take authorizations must include the suggested means of 
accomplishing the necessary monitoring and reporting that will result 
in increased knowledge of the species and of the level of taking or 
impacts on populations of marine mammals that are expected to be 
present in the proposed action area.
    Any monitoring requirement we prescribe should accomplish one or 
more of the following general goals:
    1. An increase in the probability of detecting marine mammals, both 
within defined zones of effect (thus allowing for more effective 
implementation of the mitigation) and in general to generate more data 
to contribute to the analyses mentioned below;
    2. An increase in our understanding of how many marine mammals are 
likely to be exposed to stimuli that we associate with specific adverse 
effects, such as behavioral harassment or hearing threshold shifts;
    3. An increase in our understanding of how marine mammals respond 
to stimuli expected to result in incidental take and how anticipated 
adverse effects on individuals may impact the population, stock, or 
species (specifically through effects on annual rates of recruitment or 
survival) through any of the following methods:
     Behavioral observations in the presence of stimuli 
compared to observations in the absence of stimuli (need to be able to 
accurately predict pertinent information, e.g., received level, 
distance from source);
     Physiological measurements in the presence of stimuli 
compared to observations in the absence of stimuli (need to be able to 
accurately predict pertinent information, e.g., received level, 
distance from source); and

[[Page 18590]]

     Distribution and/or abundance comparisons in times or 
areas with concentrated stimuli versus times or areas without stimuli.
    4. An increased knowledge of the affected species; or
    5. An increase in our understanding of the effectiveness of certain 
mitigation and monitoring measures.
    SpaceX submitted a monitoring plan as part of their IHA 
application. SpaceX's proposed marine mammal monitoring plan was 
created with input from NMFS and was based on similar plans that have 
been successfully implemented by other action proponents under previous 
authorizations for similar projects, specifically the USAF's monitoring 
of rocket launches from VAFB. The plan may be modified or supplemented 
based on comments or new information received from the public during 
the public comment period.
    Proposed monitoring protocols vary according to modeled sonic boom 
intensity and season. Sonic boom modeling will be performed prior to 
all boost-back events. PCBoom, a commercially available modeling 
program, or an acceptable substitute, will be used to model sonic 
booms. Launch parameters specific to each launch will be incorporated 
into each model. These include direction and trajectory, weight, 
length, engine thrust, engine plume drag, position versus time from 
initiating boost-back to additional engine burns, among other aspects. 
Various weather scenarios will be analyzed from NOAA weather records 
for the region, then run through the model. Among other factors, these 
will include the presence or absence of the jet stream, and if present, 
its direction, altitude and velocity. The type, altitude, and density 
of clouds will also be considered. From these data, the models will 
predict peak amplitudes and impact locations.

Marine Mammal Monitoring

    Marine mammal monitoring procedures will consist of the following:
     Should sonic boom model results indicate that a peak 
overpressure of 1.0 psf or greater is likely to impact VAFB, then 
acoustic and biological monitoring at VAFB will be implemented.
     If it is determined that a sonic boom of 1.0 psf or 
greater is likely to impact one of the Northern Channel Islands between 
1 March and 30 June; a sonic boom greater than 1.5 psf between 1 July 
and 30 September, and a sonic boom greater than 2.0 psf between 1 
October and 28 February, then monitoring will be conducted at the 
haulout site closest to the predicted sonic boom impact area.
     Monitoring would commence at least 72 hours prior to the 
boost-back and continue until at least 48 hours after the event.
     Monitoring data collected would include multiple surveys 
each day that record the species; number of animals; general behavior; 
presence of pups; age class; gender; and reaction to booms or other 
natural or human-caused disturbances. Environmental conditions such as 
tide, wind speed, air temperature, and swell would also be recorded.
     If the boost-back is scheduled for daylight; video 
recording of pinnipeds on NCI would be conducted during the boost-back 
in order to collect required data on reaction to launch noise.
     For launches during the harbor seal pupping season (March 
through June), follow-up surveys will be conducted within 2 weeks of 
the boost-back/landing.

Acoustic Monitoring

    Acoustic measurements of the sonic boom created during boost-back 
at the monitoring location would be recorded to determine the 
overpressure level.

Reporting

    SpaceX will submit a report within 90 days after each Falcon 9 
First Stage recovery event that includes the following information:
     Summary of activity (including dates, times, and specific 
locations of Falcon 9 First Stage recovery activities)
     Summary of monitoring measures implemented
     Detailed monitoring results and a comprehensive summary 
addressing goals of monitoring plan, including:
    [cir] Number, species, and any other relevant information regarding 
marine mammals observed and estimated exposed/taken during activities;
    [cir] Description of the observed behaviors (in both presence and 
absence of activities);
    [cir] Environmental conditions when observations were made; and
    [cir] Assessment of the implementation and effectiveness of 
monitoring measures.
    In addition to the above post-activity reports, a draft annual 
report will be submitted within 90 calendar days of the expiration of 
the proposed IHA, or within 45 calendar days prior to the effective 
date of a subsequent IHA (if applicable). The annual report will 
summarize the information from the post-activity reports, including but 
not necessarily limited to: (a) Numbers of pinnipeds present on the 
haulouts prior to commencement of Falcon 9 First Stage recovery 
activities; (b) numbers of pinnipeds that may have been harassed as 
noted by the number of pinnipeds estimated to have entered the water as 
a result of Falcon 9 First Stage recovery noise; (c) for pinnipeds that 
entered the water as a result of Falcon 9 First Stage recovery noise, 
the length of time(s) those pinnipeds remained off the haulout or 
rookery; and (d) any behavioral modifications by pinnipeds that likely 
were the result of stimuli associated with the proposed activities.
    In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner not authorized by the 
proposed IHA (if issued), such as a Level A harassment, or a take of a 
marine mammal species other than those proposed for authorization, 
SpaceX would immediately cease the specified activities and immediately 
report the incident to the Chief of the Permits and Conservation 
Division, Office of Protected Resources. The report would include the 
following information:
     Time, date, and location (latitude/longitude) of the 
incident;
     Description of the incident;
     Status of all Falcon 9 First Stage recovery activities in 
the 48 hours preceding the incident;
     Description of all marine mammal observations in the 48 
hours preceding the incident;
     Species identification or description of the animal(s) 
involved;
     Fate of the animal(s); and
     Photographs or video footage of the animal(s) (if 
equipment is available).
    Activities would not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS would work with SpaceX to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. SpaceX would not be able to 
resume their activities until notified by NMFS via letter, email, or 
telephone.
    In the event that SpaceX discovers an injured or dead marine 
mammal, and the lead MMO determines the cause of the injury or death is 
unknown and the death is relatively recent (i.e., in less than a 
moderate state of decomposition), SpaceX would immediately report the 
incident to mailto: The Chief of the Permits and Conservation Division, 
Office of Protected Resources, NMFS, and the NMFS West Coast Region 
Stranding Coordinator.
    The report would include the same information identified in the 
paragraph above. Authorized activities would be able to continue while 
NMFS reviews the circumstances of the incident.

[[Page 18591]]

NMFS would work with SpaceX to determine whether modifications in the 
activities are appropriate.
    In the event that SpaceX discovers an injured or dead marine 
mammal, and the lead MMO determines the injury or death is not 
associated with or related to the activities authorized in the IHA 
(e.g., previously wounded animal, carcass with moderate to advanced 
decomposition, or scavenger damage), SpaceX would report the incident 
to the Chief of the Permits and Conservation Division, Office of 
Protected Resources, NMFS, and NMFS West Coast Region Stranding 
Coordinator, within 24 hours of the discovery. SpaceX would provide 
photographs or video footage (if available) or other documentation of 
the stranded animal sighting to NMFS and the Marine Mammal Stranding 
Network.

Estimated Take by Incidental Harassment

    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].''
    SpaceX has requested, and NMFS proposes, authorization to take 
harbor seals, California sea lions, northern elephant seals, Steller 
sea lions, northern fur seals, and Guadalupe fur seals, incidental to 
Falcon 9 First Stage recovery activities. All anticipated takes would 
be by Level B harassment only, resulting from noise associated with 
sonic booms and involving temporary changes in behavior. Estimates of 
the number of harbor seals, California sea lions, northern elephant 
seals, Steller sea lions, northern fur seals, and Guadalupe fur seals 
that may be harassed by the proposed activities is based upon the 
number of potential events associated with Falcon 9 First Stage 
recovery activities (maximum 6 per year) and the average number of 
individuals of each species that are present in areas that will be 
exposed to the activities at levels that are expected to result in 
Level B harassment.
    In order to estimate the potential incidents of take that may occur 
incidental to the specified activity, we must first estimate the extent 
of the sound field that may be produced by the activity and then 
incorporate information about marine mammal density or abundance in the 
project area. We first provide information on applicable thresholds for 
determining effects to marine mammals before describing the information 
used in estimating the sound fields, the available marine mammal 
density or abundance information, and the method of estimating 
potential incidences of take. It should be noted that estimates of 
Level B take described below are not necessarily estimates of the 
number of individual animals that are expected to be taken; a smaller 
number of individuals may accrue a number of incidences of harassment 
per individual than for each incidence to accrue to a new individual, 
especially if those individuals display some degree of residency or 
site fidelity and the impetus to use the site (e.g., because of 
foraging opportunities) is stronger than the deterrence presented by 
the harassing activity.

Sound Thresholds

    Typically NMFS relies on the acoustic criteria shown in Table 2 to 
estimate the extent of take by Level A and/or Level B harassment that 
is expected as a result of an activity. If we relied on the acoustic 
criteria shown in Table 2, we would assume harbor seals exposed to 
airborne sound at levels at or above 90 dB rms re 20 [mu]Pa, and non-
harbor seal pinnipeds exposed to airborne sound at levels at or above 
100 dB rms re 20 [mu]Pa, would experience Level B harassment. However, 
in this case we have the benefit of more than 20 years of observational 
data on pinniped responses to the stimuli associated with the proposed 
activity that we expect to result in harassment (sonic booms) in the 
particular geographic area of the proposed activity (VAFB and the NCI). 
Therefore, we consider these data to be the best available information 
in regard to estimating take based on modeled exposures among pinnipeds 
to sounds associated with the proposed activities. These data suggest 
that pinniped reactions to sonic booms are dependent on the species, 
the age of the animal, and the intensity of the sonic boom (see Table 
4).
    As described above, data from launch monitoring by the USAF on the 
NCI and at VAFB have shown that pinniped reactions to sonic booms are 
correlated to the level of the sonic boom. Low energy sonic booms (< 
1.0 psf) have resulted in little to no behavioral responses, including 
head raising and briefly alerting but returning to normal behavior 
shortly after the stimulus. More powerful sonic booms have flushed 
animals from haulouts (but not resulted in any mortality or sustained 
decreased in numbers after the stimulus). Table 4 presents a summary of 
monitoring efforts at the NCI from 1999 to 2011. These data show that 
reactions to sonic booms tend to be insignificant below 1.0 psf and 
that, even above 1.0 psf, only a portion of the animals present react 
to the sonic boom. Therefore, for the purposes of estimating the extent 
of take that is likely to occur as a result of the proposed activities, 
we assume that Level B harassment occurs when a pinniped (on land) is 
exposed to a sonic boom at or above 1.0 psf. Therefore the number of 
expected takes by Level B harassment is based on estimates of the 
numbers of animals that would be within the area exposed to sonic booms 
at levels at or above 1.0 psf.
    The data recorded by USAF at VAFB and the NCI over the past 20 
years has also shown that pinniped reactions to sonic booms vary 
between species. As described above, little or no reaction has been 
observed in harbor seals, California sea lions, northern fur seals and 
northern elephant seals when overpressures were below 1.0 psf (data on 
responses among Steller sea lions and Guadalupe fur seals is not 
available). At the NCI sea lions have reacted more strongly to sonic 
booms than most other species. Harbor seals also appear to be more 
sensitive to sonic booms than most other pinnipeds, often resulting in 
startling and fleeing into the water. Northern fur seals generally show 
little or no reaction, and northern elephant seals generally exhibit no 
reaction at all, except perhaps a heads-up response or some stirring, 
especially if sea lions in the same area mingled with the elephant 
seals react strongly to the boom. No data is available on Steller sea 
lion or Guadalupe fur seal responses to sonic booms.

Exposure Area

    As described above, SpaceX performed acoustic modeling to estimate 
overpressure levels that would be created during the return flight of 
the Falcon 9 First Stage (Wyle, Inc. 2015). The predicted acoustic 
footprint of the sonic boom was computed using the computer program 
PCBoom (Plotkin and Grandi 2002; Page et al. 2010). Modeling was 
performed for a landing at VAFB and separately for a contingency barge 
landing (see Figures 2-1, 2-2, 2-3 and 2-4 in the IHA application).
    The model results predicted that sonic overpressures would reach up 
to 2.0 pounds psf in the immediate area around SLC-4W (see Figures 2-1 
and 2-2 in the IHA application) and an overpressure between 1.0 and 2.0 
psf would impact the coastline of VAFB

[[Page 18592]]

from approximately 8 km north of SLC-4W to approximately 18 km 
southeast of SLC-4W see (Figures 2-1 and 2-2 in the IHA application). A 
substantially larger area, including the mainland, the Pacific Ocean, 
and the NCI would experience an overpressure between 0.1 and 1.0 psf 
(see Figure 2-1 in the IHA application). In addition, San Miguel Island 
and Santa Rosa Island may experience an overpressure up to 3.1 psf and 
the west end of Santa Cruz Island may experience an overpressure up to 
1.0 psf (see Figures 2-1 and 2-3 in the IHA application). During a 
contingency barge landing event, an overpressure of up to 2.0 psf would 
impact the Pacific Ocean at the contingency landing location 
approximately 50 km offshore of VAFB. San Miguel Island and Santa Rosa 
Island would experience a sonic boom between 0.1 and 0.2 psf, while 
sonic boom overpressures on the mainland would be between 0.2 and 0.4 
psf.
    SpaceX assumes that actual sonic booms that occur during the 
proposed activities will vary slightly from the modeled sonic booms; 
therefore, when estimating take based on areas anticipated to be 
impacted by sonic booms at or above 1.0 psf, haulouts within 
approximately 8.0 km (5 miles) of modeled contour lines for sonic booms 
at or above 1.0 psf were included to be conservative. Therefore, in 
estimating take for a VAFB landing, haulouts were included from the 
areas of Point Arguello and Point Conception, all of San Miguel Island, 
the north western half of Santa Rosa Island, and northwestern quarter 
of Santa Cruz Island (see Figure 2-2 and 2-3 in the IHA application). 
For a contingency landing event, sonic booms are far enough offshore so 
that only haulouts along the northwestern edge of San Miguel Island may 
be exposed to a 1.0 psf or greater sonic boom (see Figure 2-4 in the 
IHA application). As modeling indicates that substantially more 
haulouts would be impacted by a sonic boom at or above 1.0 psf in the 
event of a landing at VAFB versus a landing at the contingency landing 
location, estimated takes are substantially higher in the event of a 
VAFB landing versus a barge landing.

Description of Take Calculation

    The take calculations presented here rely on the best data 
currently available for marine mammal populations in the project 
location. Data collected from marine mammal surveys represent the best 
available information on the occurrence of the six pinniped species in 
the project area. The quality of information available on pinniped 
abundance in the project area is varies depending on species; some 
species, such as California sea lions, are surveyed regularly at VAFB 
and the NCI, while for others, such as northern fur seals, survey data 
is largely lacking. See Table 5 for total estimated incidents of take. 
Take estimates were based on ``worst case scenario'' assumptions, as 
follows:
     All six proposed Falcon 9 First Stage recovery actions are 
assumed to result in landings at VAFB, with no landings occurring at 
the contingency barge landing location. This is a conservative 
assumption as sonic boom modeling indicates landings at VAFB are 
expected to result in a greater number of exposures to sound resulting 
in Level B harassment than would be expected for landings at the 
contingency landing location offshore. Some landings may ultimately 
occur at the contingency landing location; however, the number of 
landings at each location is not known in advance.
     All pinnipeds estimated to be in areas ensonified by sonic 
booms at or above 1.0 psf are assumed to be hauled out at the time the 
sonic boom occurs. This assumption is conservative as some animals may 
in fact be in the water with heads submerged when a sonic boom occurs 
and would therefore not be exposed to the sonic boom at a level that 
would result in Level B harassment.
     Actual sonic booms that occur during the proposed 
activities are assumed to vary slightly from the modeled sonic booms; 
therefore, when estimating take based on areas expected to be impacted 
by sonic booms at or above 1.0 psf, an additional buffer of 8.0 km (5 
miles) was added to modeled sonic boom contour lines. Thus haulouts 
that are within approximately 8.0 km (5 miles) of modeled sonic booms 
at 1.0 psf and above were included in the take estimate. This is a 
conservative assumption as it expands the area of ensonification that 
would be expected to result in Level B harassment.
    California sea lion--California sea lions are common offshore of 
VAFB and haul out on rocks and beaches along the coastline of VAFB, 
though pupping rarely occurs on the VAFB coastline. They haulout in 
large numbers on the NCI and rookeries exist on San Miguel and Santa 
Cruz islands. Based on modeling of sonic booms from Falcon 9 First 
Stage recovery activities, Level B harassment of California sea lions 
is expected to occur both at VAFB and at the NCI. Estimated take of 
California sea lions at VAFB was calculated using the largest count 
totals from monthly surveys of VAFB haulout sites from 2013-2015. These 
data were compared to the modeled sonic boom profiles. Counts from 
haulouts that were within the area expected to be ensonified by a sonic 
boom above 1.0 psf, plus the buffer of 8 km as described above, were 
included in take estimates; those haulouts outside the area expected to 
be ensonified by a sonic boom above 1.0 psf, plus the buffer of 8 km, 
were not included in the take estimate. The estimated number of 
California sea lion takes on the NCI and at Point Conception was 
derived from aerial survey data collected from 2002 to 2012 by the NOAA 
Southwest Fishery Science Center (SWFSC). The estimates are based on 
the largest number of individuals observed in the count blocks that 
fall within the area expected to be ensonified by a sonic boom above 
1.0 psf plus a radius of 8 km, based on sonic boom modeling. Estimates 
of Level B harassment for California sea lions are shown in Table 5.
    Harbor Seal--Pacific harbor seals are the most common marine mammal 
inhabiting VAFB, congregating on several rocky haul-out sites along the 
VAFB coastline. They also haul out, breed, and pup in isolated beaches 
and coves throughout the coasts of the NCI. Based on modeling of sonic 
booms from Falcon 9 First Stage recovery activities, Level B harassment 
of harbor seals is expected to occur both at VAFB and at the NCI. 
Estimated take of harbor seals at VAFB was calculated using the largest 
count totals from monthly surveys of VAFB haulout sites from 2013-2015. 
These data were compared to the modeled sonic boom profiles. Counts 
from haulouts that were within the area expected to be ensonified by a 
sonic boom above 1.0 psf plus a radius of 8 km were included in take 
estimates; those haulouts outside the area expected to be ensonified by 
a sonic boom above 1.0 psf plus a radius of 8 km were not included in 
the take estimate. The estimated number of harbor seal takes on the NCI 
and at Point Conception was derived from aerial survey data collected 
from 2002 to 2012 by the NOAA SWFSC. The estimates are based on the 
largest number of individuals observed in the count blocks that fall 
within the area expected to be ensonified by a sonic boom above 1.0 psf 
plus a radius of 8 km, based on sonic boom modeling.
    It should be noted that total take estimates shown in Table 5 
represent incidents of exposure to sound resulting in Level B 
harassment from the proposed activities, and not estimates of the 
number of individual harbor seals exposed. As described above, harbor 
seals display a high degree of site fidelity to their preferred haulout 
sites,

[[Page 18593]]

and are non-migratory, rarely traveling more than 50 km from their 
haulout sites. Thus, while the estimated abundance of the California 
stock of Pacific harbor seals is 30,968 (Carretta et al. 2015), a 
substantially smaller number of individual harbor seals is expected to 
occur within the project area. The number of harbor seals expected to 
be taken by Level B harassment, per Falcon 9 First Stage recovery 
action, is 2,157 (Table 5). We expect that, because of harbor seals' 
site fidelity to haulout locations at VAFB and the NCI, and because of 
their limited ranges, the same individuals are likely to be taken 
repeatedly over the course of the proposed activities (six Falcon 9 
First Stage recovery actions). Estimates of Level B harassment for 
harbor seals are shown in Table 5.
    Steller Sea Lion--Steller sea lions occur in small numbers at VAFB 
(maximum 16 individuals observed at any time) and on San Miguel Island 
(maximum 4 individuals recorded at any time). They have not been 
observed on the Channel Islands other than San Miguel Island and they 
not currently have rookeries on the NCI or at VAFB. Estimated take of 
Steller sea lions at VAFB was calculated using the largest count totals 
from monthly surveys of VAFB from 2013-2015. These data were compared 
to the modeled sonic boom profiles. Counts from haulouts that were 
within the area expected to be ensonified by a sonic boom above 1.0 psf 
plus a radius of 8 km were included in take estimates; those haulouts 
outside the area expected to be ensonified by a sonic boom above 1.0 
psf plus a radius of 8 km were not included in the take estimate. 
Estimates of Level B harassment for Steller sea lions are shown in 
Table 5.
    Northern elephant seal--Northern elephant seals haul out 
sporadically on rocks and beaches along the coastline of VAFB and at 
Point Conception, but they do not currently breed or pup at VAFB or at 
Point Conception. Northern elephant seals have rookeries on San Miguel 
Island and Santa Rosa Island. They are rarely seen on Santa Cruz Island 
and Anacapa Island. Based on modeling of sonic booms from Falcon 9 
First Stage recovery activities, Level B harassment of harbor seals is 
expected to occur both at VAFB and at the NCI.
    Estimated take of northern elephant seals at VAFB was calculated 
using the largest count totals from monthly surveys of VAFB haulout 
sites from 2013-2015. These data were compared to the modeled sonic 
boom profiles. Counts from haulouts that were within the area expected 
to be ensonified by a sonic boom above 1.0 psf plus a radius of 8 km 
were included in take estimates; those haulouts outside the area 
expected to be ensonified by a sonic boom above 1.0 psf plus a radius 
of 8 km were not included in the take estimate. The estimated number of 
northern elephant seal takes on the NCI and at Point Conception was 
derived from aerial survey data collected from 2002 to 2012 by the NOAA 
SWFSC. The estimates are based on the largest number of individuals 
observed in the count blocks that fall within the area expected to be 
ensonified by a sonic boom above 1.0 psf plus a radius of 8 km, based 
on sonic boom modeling.
    As described above, monitoring data has shown that reactions to 
sonic booms among pinnipeds vary between species, with northern 
elephant seals consistently showing little or no reaction (Table 4). 
USAF launch monitoring data shows that northern elephant seals have 
never been observed responding to sonic booms. No elephant seal has 
been observed flushing to the water in response to a sonic boom. 
Because of the data showing that elephant seals consistently show 
little to no reaction to the sonic booms, we conservatively estimate 
that 10 percent of northern elephant seal exposures to sonic booms at 
or above 1.0 psf will result in Level B harassment. Estimates of Level 
B harassment for northern elephant seals are shown in Table 5.
    Northern fur seal--Northern fur seals have rookeries on San Miguel 
Island, the only island in the NCI on which they have been observed. No 
haulout or rookery sites exist for northern fur seals at VAFB or on the 
mainland coast, thus take from sonic booms is only expected on San 
Miguel Island and not on the mainland. Comprehensive count data for 
northern fur seals on San Miguel Island are not available. Estimated 
take of northern fur seals was derived from northern fur seals pup and 
bull census data (Testa 2013), and personal communications with subject 
matter experts based at the NMFS National Marine Mammal Laboratory. 
Northern fur seal abundance on San Miguel Island varies substantially 
depending on the season, with a maximum of 6,000-8,000 seals hauled out 
on the western end of the island and at Castle Rock (~1 km northwest of 
San Miguel Island) during peak pupping season in July; the number of 
seals on San Miguel Island then decreases steadily from August until 
November, when very few seals are present. The number of seals on the 
island does not begin to increase again until the following June (pers. 
comm., T. Orr, NMFS NMML, to J. Carduner, NMFS, 2/27/16). As the dates 
of Falcon 9 First Stage recovery activities are not known, the 
activities could occur when the maximum number or the minimum number of 
fur seals is present, depending on season. We therefore estimated an 
average of 5,000 northern fur seals would be present in the area 
affected by sonic booms above 1.0 psf.
    As described above, monitoring data has shown that reactions to 
sonic booms among pinnipeds vary between species, with northern fur 
seals consistently showing little or no reaction (Table 4). As 
described above, launch monitoring data shows that northern fur seals 
sometimes alert to sonic booms but have never been observed flushing to 
the water in response to sonic booms. Because of the data showing that 
fur seals consistently show little to no reaction to sonic booms, we 
conservatively estimate that 10 percent of northern fur seal exposures 
to sonic booms at or above 1.0 psf will result in Level B harassment. 
Estimates of Level B harassment for northern fur seals are shown in 
Table 5.
    Guadalupe fur seal--There are estimated to be approximately 20-25 
individual Guadalupe fur seals that have fidelity to San Miguel Island. 
The highest number of individuals observed at any one time on San 
Miguel Island is thirteen. No haul-out or rookery sites exist for 
Guadalupe fur seals on the mainland coast, including VAFB. 
Comprehensive survey data on Guadalupe fur seals in the NCI is not 
readily available. The estimated number of takes of Guadalupe fur seals 
was based the maximum number of Guadalupe fur seals observed at any one 
time on San Miguel Island (pers. comm., J. LaBonte, ManTech, to J. 
Carduner, NMFS, Feb 29, 2016). Estimates of Level B harassment for 
Guadalupe fur seals are shown in Table 5.
    As described above, the take estimates shown in Table 5 are 
considered reasonable estimates of the number of marine mammal 
exposures to sound resulting in Level B harassment that are likely to 
occur over the course of the project, and not necessarily the number of 
individual animals exposed.

[[Page 18594]]



 Table 5--Number of Potential Incidental Takes of Marine Mammals, and Percentage of Stock Abundance, as a Result
                                           of the Proposed Activities
----------------------------------------------------------------------------------------------------------------
                                                                             Total estimated
                                                       Estimated takes per    takes over the     Percentage of
             Species              Geographic location     Falcon 9 First     duration of  the   stock abundance
                                                          Stage recovery         proposed       estimated taken
                                                              action          IHA[supcaret]
----------------------------------------------------------------------------------------------------------------
Harbor Seal.....................  VAFB \a\...........  366................             12,942               7% *
                                  Pt. Conception \b\.  488................
                                  San Miguel Island    752................
                                   \b\.
                                  Santa Rosa Island    412................
                                   \b\.
                                  Santa Cruz Island    139................
                                   \b\.
California Sea Lion.............  VAFB \a\...........  416................             56,496                19%
                                  Pt. Conception.....  n/a................
                                  San Miguel Island    9,000..............
                                   \c\.
                                  Santa Rosa Island
                                   \c\.
                                  Santa Cruz Island
                                   \c\.
Northern Elephant Seal..........  VAFB \a\...........  19.................                960               0.5%
                                  Pt. Conception \d\.  1..................
                                  San Miguel Island
                                   \c\.
                                  Santa Rosa Island    150................
                                   \c\.
                                  Santa Cruz Island
                                   \c\.
Steller Sea Lion................  VAFB \a\...........  16.................                120               0.2%
                                  Pt. Conception.....  n/a................
                                  San Miguel Island..  4..................
                                  Santa Rosa Island..  n/a................
                                  Santa Cruz Island..  n/a................
Northern Fur Seal...............  VAFB...............  n/a................              3,000                23%
                                  Pt. Conception.....  n/a................
                                  San Miguel Island    500................
                                   \c\.
                                  Santa Rosa Island..  n/a................
                                  Santa Cruz Island..  n/a................
Guadalupe Fur Seal..............  VAFB...............  n/a................                 18               0.2%
                                  Pt. Conception.....  n/a................
                                  San Miguel Island    3..................
                                   \e\.
                                  Santa Rosa Island..  n/a................
                                  Santa Cruz Island..  n/a................
----------------------------------------------------------------------------------------------------------------
\a\ VAFB monthly marine mammal survey data 2013-2015 (ManTech SRS Technologies, Inc. 2014, 2015 and VAFB,
  unpubl. data).
\b\ NOAA Fisheries aerial survey data June 2002 and May 2004 (M. Lowry, NOAA Fisheries, unpubl. data).
\c\ Testa 2013; USAF 2013; pers. comm., T. Orr, NMFS NMML, to J. Carduner, NMFS, Feb 27, 2016.
\d\ NOAA Fisheries aerial survey data February 2010 (M. Lowry, NOAA Fisheries, unpubl. data).
\e\ DeLong and Melin 2000; J. Harris, NOAA Fisheries, pers. comm.
[supcaret] Based on six Falcon 9 First Stage recovery actions, with SLC-4W landings, per year.
* For harbor seals, estimated percentage of stock abundance taken is based on estimated number of individuals
  taken versus estimated total exposures.

Analyses and Preliminary Determinations

Negligible Impact Analysis

    NMFS has defined ``negligible impact'' in 50 CFR 216.103 as ``. . . 
an impact resulting from the specified activity that cannot be 
reasonably expected to, and is not reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival.'' A negligible impact finding is based on the 
lack of likely adverse effects on annual rates of recruitment or 
survival (i.e., population-level effects). An estimate of the number of 
Level B harassment takes alone is not enough information on which to 
base an impact determination. In addition to considering estimates of 
the number of marine mammals that might be ``taken'' through behavioral 
harassment, we consider other factors, such as the likely nature of any 
responses (e.g., intensity, duration), the context of any responses 
(e.g., critical reproductive time or location, migration), as well as 
the number and nature of estimated Level A harassment takes, the number 
of estimated mortalities, and effects on habitat.
    To avoid repetition, the discussion of our analyses applies to all 
the species listed in Table X, given that the anticipated effects of 
this activity on these different marine mammal stocks are expected to 
be similar. There is no information about the nature or severity of the 
impacts, or the size, status, or structure of any of these species or 
stocks that would lead to a different analysis for this activity.
    Activities associated with the proposed Falcon 9 First Stage 
recovery project, as outlined previously, have the potential to disturb 
or displace marine mammals. Specifically, the specified activities may 
result in take, in the form of Level B harassment (behavioral 
disturbance) only, from in-air sounds generated from sonic booms. 
Potential takes could occur if marine mammals are hauled out in areas 
where a sonic boom above 1.0 psf occurs, which is considered likely 
given the modeled acoustic footprint of the proposed activities and the 
occurrence of pinnipeds in the project area. Effects on individuals 
that are taken by Level B harassment, on the basis of reports in the 
literature as well as monitoring from similar activities that have 
received incidental take authorizations from NMFS, will likely be 
limited to reactions such as alerting to the noise, with some animals 
possibly moving toward or entering the water, depending on the species 
and the psf associated with the sonic boom. Repeated exposures of 
individuals to levels of sound that may cause Level B harassment are 
unlikely to result in hearing impairment or to significantly disrupt 
foraging behavior. Thus, even repeated Level B harassment of some

[[Page 18595]]

small subset of the overall stock is unlikely to result in any 
significant realized decrease in fitness to those individuals, and thus 
would not result in any adverse impact to the stock as a whole. Level B 
harassment will be reduced to the level of least practicable impact 
through use of mitigation measures described above.
    If a marine mammal responds to a stimulus by changing its behavior 
(e.g., through relatively minor changes in locomotion direction/speed), 
the response may or may not constitute taking at the individual level, 
and is unlikely to affect the stock or the species as a whole. However, 
if a sound source displaces marine mammals from an important feeding or 
breeding area for a prolonged period, impacts on animals or on the 
stock or species could potentially be significant (e.g., Lusseau and 
Bejder, 2007; Weilgart, 2007). Flushing of pinnipeds into the water has 
the potential to result in mother-pup separation, or could result in 
stampede, either of which could potentially result in serious injury or 
mortality and thereby could potentially impact the stock or species. 
However, based on the best available information, no serious injury or 
mortality of marine mammals is anticipated as a result of the proposed 
activities.
    Even in the instances of pinnipeds being behaviorally disturbed by 
sonic booms from rocket launches at VAFB, no evidence has been 
presented of abnormal behavior, injuries or mortalities, or pup 
abandonment as a result of sonic booms (SAIC 2013). These findings came 
as a result of more than two decades of surveys at VAFB and the NCI 
(MMCG and SAIC, 2012). Post-launch monitoring generally reveals a 
return to normal patterns within minutes up to an hour or two of each 
launch, regardless of species. For instance, eight space vehicle 
launches occurred from north VAFB, near the Spur Road and Purisima 
Point haul-out sites, during the period 7 February 2009 through 6 
February 2014. Of these eight Delta II and Taurus launches, three 
occurred during the harbor seal pupping season. The continued use of 
the Spur Road and Purisima Point haulout sites indicates that it is 
unlikely that these rocket launches (and associated sonic booms) 
resulted in long-term disturbances of pinnipeds using the haulout 
sites. Moreover, adverse cumulative impacts from launches were not 
observed at this site. San Miguel Island represents the most important 
pinniped rookery in the lower 48 states, and as such extensive research 
has been conducted there for decades. From this research, as well as 
stock assessment reports, it is clear that VAFB operations (including 
associated sonic booms) have not had any significant impacts on San 
Miguel Island rookeries and haulouts (SAIC 2012). Based on this 
extensive record, we believe the likelihood of serious injury or 
mortality of any marine mammal as a result of the proposed activities 
is so low as to be discountable. Thus we do not anticipate Level A 
harassment will occur as a result of the proposed activities and do not 
propose to authorize take in the form of Level A harassment.
    The activities analyzed here are substantially similar to other 
activities that have received MMPA incidental take authorizations 
previously, including Letters of Authorization for USAF launches of 
space launch vehicles at VAFB, which have occurred for over 20 years 
with no reported injuries or mortalities to marine mammals, and no 
known long-term adverse consequences to marine mammals from behavioral 
harassment. As described above, several cetacean species occur within 
the project area, however no cetaceans are expected to be affected by 
the proposed activities.
    In summary, this negligible impact analysis is founded on the 
following factors:
    1. The possibility of injury, serious injury, or mortality may 
reasonably be considered discountable;
    2. The anticipated incidences of Level B harassment consist of, at 
worst, temporary modifications in behavior (i.e., short distance 
movements and occasional flushing into the water with return to 
haulouts within at most two days), which are not expected to adversely 
affect the fitness of any individuals;
    3. The considerable evidence, based on over 20 years of monitoring 
data, suggesting no long-term changes in the use by pinnipeds of 
rookeries and haulouts in the project area as a result of sonic booms; 
and
    4. The presumed efficacy of planned mitigation measures in reducing 
the effects of the specified activity to the level of least practicable 
impact.
    In combination, we believe that these factors, as well as the 
available body of evidence from other similar activities, demonstrate 
that the potential effects of the specified activity will be short-term 
on individual animals. The specified activity is not expected to impact 
rates of recruitment or survival and will therefore not result in 
population-level impacts. Based on the analysis contained herein of the 
likely effects of the specified activity on marine mammals and their 
habitat, and taking into consideration the implementation of the 
proposed monitoring and mitigation measures, we preliminarily find that 
the total marine mammal take from SpaceX's Falcon 9 First Stage 
recovery activities will have a negligible impact on the affected 
marine mammal species or stocks.

Small Numbers Analysis

    The numbers of proposed authorized takes would be considered small 
relative to the relevant stocks or populations (23 percent for northern 
fur seals; 19 percent for California sea lions; 7 percent for Pacific 
harbor seals; less than 1 percent each for northern elephant seals, 
Guadalupe fur seals and Steller sea lions). But, it is important to 
note that the number of expected takes does not necessarily represent 
of the number of individual animals expected to be taken. Our small 
numbers analysis accounts for this fact. Multiple exposures to Level B 
harassment can accrue to the same individuals over the course of an 
activity that occurs multiple times in the same area (such as SpaceX's 
proposed activity). This is especially likely in the case of species 
that have limited ranges and that have site fidelity to a location 
within the project area, as is the case with Pacific harbor seals.
    As described above, harbor seals are non-migratory, rarely 
traveling more than 50 km from their haul-out sites. Thus, while the 
estimated abundance of the California stock of Pacific harbor seals is 
30,968 (Carretta et al. 2015), a substantially smaller number of 
individual harbor seals is expected to occur within the project area. 
We expect that, because of harbor seals' site fidelity to locations at 
VAFB and the NCI, and because of their limited ranges, the same 
individuals are likely to be taken repeatedly over the course of the 
proposed activities (maximum of six Falcon 9 First Stage recovery 
actions). Therefore the number of exposures to Level B harassment over 
the course of proposed authorization (the total number of takes shown 
in Table 5) is expected to accrue to a much smaller number of 
individuals. The maximum number of harbor seals expected to be taken by 
Level B harassment, per Falcon 9 First Stage recovery action, is 2,157. 
As we believe the same individuals are likely to be taken repeatedly 
over the course of the proposed activities, we use the estimate of 
2,157 individual animals taken per Falcon 9 First Stage recovery 
activity for the purposes of estimating the percentage of the stock 
abundance likely to be taken.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals

[[Page 18596]]

and their habitat, and taking into consideration the implementation of 
the mitigation and monitoring measures, we preliminarily find that 
small numbers of marine mammals will be taken relative to the 
populations of the affected species or stocks.

Impact on Availability of Affected Species for Taking for Subsistence 
Uses

    Potential impacts resulting from the proposed activities will be 
limited to individuals of marine mammal species located in areas that 
have no subsistence requirements. Therefore, no impacts on the 
availability of marine mammal species or stocks for subsistence use are 
expected.

National Environmental Policy Act (NEPA)

    The U.S. Air Force has prepared a Draft Environmental Assessment 
(EA) in accordance with NEPA and the regulations published by the 
Council on Environmental Quality. It will be posted on the NMFS Web 
site (at www.nmfs.noaa.gov/pr/permits/incidental/) concurrently with 
the publication of this proposed IHA. NMFS will independently evaluate 
the EA and determine whether or not to adopt it. We may prepare a 
separate NEPA analysis and incorporate relevant portions of USAF's EA 
by reference. Information in SpaceX's application, the EA, and this 
notice collectively provide the environmental information related to 
proposed issuance of the IHA for public review and comment. We will 
review all comments submitted in response to this notice as we complete 
the NEPA process, including a decision of whether to sign a Finding of 
No Significant Impact (FONSI), prior to a final decision on the IHA 
request.

Endangered Species Act (ESA)

    There is one marine mammal species (Guadalupe fur seal) listed 
under the ESA with confirmed occurrence in the area expected to be 
impacted by the proposed activities. The NMFS West Coast Region 
Protected Resources Division has determined that the NMFS Permits and 
Conservation Division's proposed authorization of SpaceX's Falcon 9 
First Stage recovery activities are not likely to adversely affect the 
Guadalupe fur seal. Therefore, formal ESA section 7 consultation on 
this proposed authorization is not required.

Proposed Authorization

    As a result of these preliminary determinations, we propose to 
issue an IHA to SpaceX, to conduct the described Falcon 9 First Stage 
recovery activities at Vandenberg Air Force Base, in the Pacific Ocean 
offshore Vandenberg Air Force Base, and at the Northern Channel 
Islands, California, from June 30, 2016 through June 29, 2017, provided 
the previously mentioned mitigation, monitoring, and reporting 
requirements are incorporated. The proposed IHA language is provided 
next.
    This section contains a draft of the IHA itself. The wording 
contained in this section is proposed for inclusion in the IHA (if 
issued).
    1. This Incidental Harassment Authorization (IHA) is valid from 
June 30, 2016 through June 29, 2017.
    (a) This IHA is valid only for Falcon 9 First Stage recovery 
activities at Vandenberg Air Force Base, in the Pacific Ocean offshore 
Vandenberg Air Force Base, and at the Northern Channel Islands, 
California.
2. General Conditions
    (a) A copy of this IHA must be in the possession of SpaceX, its 
designees, and work crew personnel operating under the authority of 
this IHA.
    (b) The species authorized for taking are the Pacific harbor seal 
(Phoca vitulina richardii), California sea lion (Zalophus 
californianus), Steller sea lion (eastern Distinct Population Segment, 
or DPS) (Eumetopias jubatus), northern elephant seal (Mirounga 
angustirostris), northern fur seal (Callorhinus ursinus), and Guadalupe 
fur seal (Arctocephalus townsendi).
    (c) The taking, by Level B harassment only, is limited to the 
species listed in condition 3(b). See Table 5 in the proposed IHA 
authorization for numbers of take authorized.
    (d) The taking by injury (Level A harassment), serious injury, or 
death of any of the species listed in condition 3(b) of the 
Authorization or any taking of any other species of marine mammal is 
prohibited and may result in the modification, suspension, or 
revocation of this IHA.
3. Mitigation Measures
    The holder of this Authorization is required to implement the 
following mitigation measure:
    (a) Unless constrained by other factors including human safety or 
national security concerns, launches will be scheduled to avoid, 
whenever possible, boost-backs and landings during the harbor seal 
pupping season of March through June.
4. Monitoring
    The holder of this Authorization is required to conduct marine 
mammal and acoustic monitoring as described below.
    (a) SpaceX must notify the Administrator, West Coast Region, NMFS, 
by letter or telephone, at least 2 weeks prior to activities possibly 
involving the taking of marine mammals;
    (b) To conduct monitoring of Falcon 9 First Stage recovery 
activities, SpaceX must designate qualified, on-site individuals 
approved in advance by NMFS;
    (c) If sonic boom model results indicate that a peak overpressure 
of 1.0 psf or greater is likely to impact VAFB, then acoustic and 
biological monitoring at VAFB will be implemented.
    (d) If sonic boom model results indicate that a peak overpressure 
of 1.0 psf or greater is predicted to impact the Channel Islands 
between March 1 and June 30, greater than 1.5 psf between July 1 and 
September 30, and greater than 2.0 psf between October 1 and February 
28, monitoring of haulout sites on the Channel Islands will be 
implemented. Monitoring will be conducted at the haulout site closest 
to the predicted sonic boom impact area;
    (e) Monitoring will be conducted for at least 72 hours prior to any 
planned Falcon 9 First Stage recovery and continue until at least 48 
hours after the event;
    (f) For launches during the harbor seal pupping season (March 
through June), follow-up surveys will be conducted within 2 weeks of 
the Falcon 9 First Stage recovery to monitor for any long-term adverse 
effects on marine mammals;
    (g) If Falcon 9 First Stage recovery is scheduled during daylight, 
time-lapse photography or video recording will be used to document the 
behavior of marine mammals during Falcon 9 First Stage recovery 
activities;
    (h) Monitoring will include multiple surveys each day that record 
the species, number of animals, general behavior, presence of pups, age 
class, gender and reaction to noise associated with Falcon 9 First 
Stage recovery, sonic booms or other natural or human caused 
disturbances, in addition to recording environmental conditions such as 
tide, wind speed, air temperature, and swell; and
    (i) Acoustic measurements of the sonic boom created during boost-
back at the monitoring location will be recorded to determine the 
overpressure level.
5. Reporting
    The holder of this Authorization is required to:
    (a) Submit a report to the Office of Protected Resources, NMFS, and 
the West Coast Regional Administrator, NMFS, within 60 days after each 
Falcon

[[Page 18597]]

9 First Stage recovery action. This report must contain the following 
information:
    (1) Date(s) and time(s) of the Falcon 9 First Stage recovery 
action;
    (2) Design of the monitoring program; and
    (3) Results of the monitoring program, including, but not 
necessarily limited to:
    (i) Numbers of pinnipeds present on the haulout prior to the Falcon 
9 First Stage recovery;
    (ii) Numbers of pinnipeds that may have been harassed as noted by 
the number of pinnipeds estimated to have moved more than one meter or 
entered the water as a result of Falcon 9 First Stage recovery 
activities;
    (iii) For pinnipeds estimated to have entered the water as a result 
of Falcon 9 First Stage recovery noise, the length of time pinnipeds 
remained off the haulout or rookery;
    (v) Any other observed behavioral modifications by pinnipeds that 
were likely the result of Falcon 9 First Stage recovery activities, 
including sonic boom; and
    (vi) Results of acoustic monitoring including comparisons of 
modeled sonic booms with actual acoustic recordings of sonic booms.
    (b) Submit an annual report on all monitoring conducted under the 
IHA. A draft of the annual report must be submitted within 90 calendar 
days of the expiration of this IHA, or, within 45 calendar days of the 
renewal of the IHA (if applicable). A final annual report will be 
prepared and submitted within 30 days following resolution of comments 
on the draft report from NMFS. The annual report will summarize the 
information from the 60-day post-activity reports, including but not 
necessarily limited to:
    (1) Date(s) and time(s) of the Falcon 9 First Stage recovery 
action;
    (2) Design of the monitoring program; and
    (3) Results of the monitoring program, including, but not 
necessarily limited to:
    (i) Numbers of pinnipeds present on the haulout prior to the Falcon 
9 First Stage recovery;
    (ii) Numbers of pinnipeds that may have been harassed as noted by 
the number of pinnipeds estimated to have entered the water as a result 
of Falcon 9 First Stage recovery activities;
    (iii) For pinnipeds estimated to have moved more than one meter or 
entered the water as a result of Falcon 9 First Stage recovery noise, 
the length of time pinnipeds remained off the haulout or rookery;
    (v) Any other observed behavioral modifications by pinnipeds that 
were likely the result of Falcon 9 First Stage recovery activities, 
including sonic boom;
    (vi) Any cumulative impacts on marine mammals as a result of the 
activities, such as long term reductions in the number of pinnipeds at 
haulouts as a result of the activities; and
    (vii) Results of acoustic monitoring including comparisons of 
modeled sonic booms with actual acoustic recordings of sonic booms.
    (c) Reporting injured or dead marine mammals:
    (1) In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner prohibited by this IHA 
(as determined by the lead marine mammal observer), such as an injury 
(Level A harassment), serious injury, or mortality, SpaceX will 
immediately cease the specified activities and report the incident to 
the Office of Protected Resources, NMFS, and the West Coast Regional 
Stranding Coordinator, NMFS. The report must include the following 
information:
    A. Time and date of the incident;
    B. Description of the incident;
    C. Status of all Falcon 9 First Stage recovery activities in the 48 
hours preceding the incident;
    D. Description of all marine mammal observations in the 48 hours 
preceding the incident;
    E. Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);
    F. Species identification or description of the animal(s) involved;
    G. Fate of the animal(s); and
    H. Photographs or video footage of the animal(s).
    Activities will not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS will work with SpaceX to 
determine what measures are necessary to minimize the likelihood of 
further prohibited take and ensure MMPA compliance. SpaceX may not 
resume their activities until notified by NMFS via letter, email, or 
telephone.
    (2) In the event that SpaceX discovers an injured or dead marine 
mammal, and the lead observer determines that the cause of the injury 
or death is unknown and the death is relatively recent (e.g., in less 
than a moderate state of decomposition), SpaceX will immediately report 
the incident to the Office of Protected Resources, NMFS, and the West 
Coast Regional Stranding Coordinator, NMFS.
    The report must include the same information identified in 6(c)(i) 
of this IHA. Activities may continue while NMFS reviews the 
circumstances of the incident and makes a final determination on the 
cause of the reported injury or death. NMFS will work with SpaceX to 
determine whether additional mitigation measures or modifications to 
the activities are appropriate.
    (3) In the event that SpaceX discovers an injured or dead marine 
mammal, and the lead observer determines that the injury or death is 
not associated with or related to the activities authorized in the IHA 
(e.g., previously wounded animal, carcass with moderate to advanced 
decomposition, scavenger damage), SpaceX will report the incident to 
the Office of Protected Resources, NMFS, and the West Coast Regional 
Stranding Coordinator, NMFS, within 24 hours of the discovery. SpaceX 
will provide photographs or video footage or other documentation of the 
stranded animal sighting to NMFS. The cause of injury or death may be 
subject to review and a final determination by NMFS.
6. Modification and suspension
    (a) This IHA may be modified, suspended or withdrawn if the holder 
fails to abide by the conditions prescribed herein, or if NMFS 
determines that the authorized taking is having more than a negligible 
impact on the species or stock of affected marine mammals.

Request for Public Comments

    We request comment on our analysis, the draft authorization, and 
any other aspect of this Notice of Proposed IHA for SpaceX Falcon 9 
First Stage recovery activities. Please include with your comments any 
supporting data or literature citations to help inform our final 
decision on SpaceX's request for an MMPA authorization.

    Dated: March 25, 2016.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2016-07191 Filed 3-30-16; 8:45 am]
 BILLING CODE 3510-22-P