Small Takes of Marine Mammals Incidental to Specified Activities; Explosives Testing at Eglin Air Force Base, FL

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[I.D. 092498A]

Small Takes of Marine Mammals Incidental to Specified Activities;

Explosives Testing at Eglin Air Force Base, FL

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and

Atmospheric Administration (NOAA), Commerce.

ACTION: Notice of issuance of an incidental harassment authorization.

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SUMMARY: In accordance with provisions of the Marine Mammal Protection

Act (MMPA), as amended, notification is hereby given that an Incidental

Harassment Authorization (IHA) has been issued to the U.S. Air Force to

take small numbers of bottlenose dolphins, spotted dolphins, and

possibly other cetacean species by harassment and non-serious injury

incidental to explosive testing of obstacle and mine clearance systems

at Eglin Air Force Base (Eglin), FL.

DATES: This authorization is effective from December 1, 1998, through

March 31, 1999.

ADDRESSES: A copy of the application and draft environmental

assessments (EAs) may be obtained by writing to the Chief, Marine

Mammal Division, Office of Protected Resources, National Marine

Fisheries Service, 1315 East-West Highway, Silver Spring, MD 20910-

3225, or by telephoning one of the contacts listed here.

FOR FURTHER INFORMATION CONTACT: Kenneth Hollingshead 301-713-2055, or

David Bernhart, 727-570-5312.

SUPPLEMENTARY INFORMATION:

Background

Section 101(a)(5)(A) of the MMPA (16 U.S.C. 1361 et seq.) directs

the Secretary of Commerce to allow, upon request, the incidental, but

not intentional, taking of marine mammals by U.S. citizens who engage

in a specified activity (other than commercial fishing) within a

specified geographical region if certain findings are made and

regulations are issued.

Permission may be granted if NMFS finds that the taking will have a

negligible impact on the species or stock(s) and will not have an

unmitigable adverse impact on the availability of the species or

stock(s) for subsistence uses and that the permissible methods of

taking and requirements pertaining to the monitoring and reporting of

such taking are set forth. 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.''

Subsection 101(a)(5)(D) of the MMPA established an expedited

process by which U.S. citizens can apply for an authorization to

incidentally take small numbers of marine mammals by harassment for a

period of up to 1 year. The MMPA defines ``harassment'' as:

...any act of pursuit, torment, or annoyance which (a) has the

potential to injure a marine mammal or marine mammal stock in the

wild; or (b) 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.

Subsection 101(a)(5)(D) establishes a 45-day time limit for NMFS

review of an application followed by a 30-day public notice and a

comment period on any proposed authorizations for the incidental

harassment of small numbers of marine mammals. Within 45 days of the

close of the comment period, NMFS must either issue or deny issuance of

the authorization.

Summary of Request

On July 20, 1998, NMFS received a complete application from the Air

Force Development Test Center, Department of the Air Force, Eglin. The

Air Force, in cooperation with the Naval Surface Warfare Center-Coastal

Systems Station (NSWC-CSS), U.S. Navy, is requesting an authorization

to take, by harassment and non-serious injury, bottlenose dolphins

(Tursiops truncatus), spotted dolphins (Stenella plagiodon), and

possibly other cetacean species incidental to explosive testing of

obstacle and mine clearance systems at Eglin. Eglin is located in the

Florida Panhandle, approximately midway between the cities of Pensacola

and Panama City, FL. The location of the proposed action is on the

beach areas on Santa Rosa Island (SRI), approximately 27 kilometers

(km)(17 miles (mi)) west of Destin, FL.

The Navy's current capability to clear obstacles and mines in the

surf zone is limited to the hand placement of explosive charges by Navy

combat swimmers. The effectiveness of this capability is limited by the

ability of swimmers to locate submerged targets and to carry sufficient

explosives to destroy the targets. Such operations are considered

highly hazardous, and the reliability of obstacle removal is considered

to be poor. To facilitate U.S. Marine amphibious assaults, the U.S.

Navy is committed to developing and testing methods to safely and

effectively clear a path through such obstacles.

NWSC-CSS has requested permission from Eglin to test four anti-mine

systems in the shallow surf zone along U.S. Air Force-controlled lands

of SRI. The four test systems are the Shallow Water Assault Breaching

(SABRE) system, the Distributed Explosive Technology (DET) system, the

MK-82 general purpose bombs (GPBs), and the MK-5 Mine Clearance System

(MCS).

The proposed action is to perform up to a total of 10 underwater

detonation tests (2 tests using the SABRE system and up to 8 tests

using the DET array); and a series of tests of explosive systems at

Eglin.

In order to avoid impacting the endangered West Indian manatee

(Trichiechus manatus)(which is more commonly found south of the region

and during warmer months) and sea turtles, tests will be conducted in

the fall and winter 1998/99. While a brief description of the four

systems proposed for testing is included here, more detailed

descriptions of the activity and the expected impact can be found in

the application and in the two EAs on the activities. These documents

are available upon request (see ADDRESSES).

SABRE System

An operational full-length SABRE-line charge consists of 130 10-

pound (lb)(4.5 kg) net explosive weight (N.E.W.) charges on 3-ft (0.9

m) centers which is deployed from a Landing Craft Air-Cushion (LCAC) by

an MK-22 Mod 4 rocket motor. Each charge consists of approximately 9.6

lb (4.3 kg) of PBXN-103 explosive and a W-11 booster, weighing

approximately 0.4 lb (0.2 kg). A detonating cord runs through the

centers of the booster and main charge.

For the two proposed tests, a total of 22 and 23 SABRE charges will

be hand-laid on the sea bottom, perpendicular to the beach in 3 ft (.91

m) and 10 ft (3.0 m) of water, respectively. For both tests, the

detonation sequence will be from the offshore end toward the beach. For

these events, 27 to 31 inert mines will be placed perpendicular to the

line charge and parallel to the shoreline. Total NE.W. of the SABRE

tests will be 221 lb (100.2 kg) and 232 lb (105.2 kg), respectively.

DET System

An operational, full-size DET array consists of parallel lines of

detonating cord, whose overall footprint is 180 by 180 ft (54.9 m by

54.9 m). The array is

[[Page 67670]]

packed in a container and launched from an LCAC by two MK-22 Mod 4

rocket motors for expansion and subsequent deployment.

Full-scale systems are not required for these tests. Previous tests

have shown that partial-length SABRE segments and partial-size DET

arrays are adequate for evaluations. The data acquired from small-scale

tests can be scaled up in order to make predictions for military

applications. Thus, for the DET system, the Navy is proposing to use an

11-ft by 60-ft (3.3 m by 18.3 m) DET array in 3 ft (0.9 m) of water.

There will be eight separate DET events, spanning several days, with

two to three arrays tested per day. The NE.W. of each array is 42 lb

(19 kg), with arrays being detonated at the seaward end. Each array

will be placed above a maximum of four live mines consisting of either

22 or 26.4 lb (10 or 12 kg) of explosive. Therefore, depending upon the

mine type, total NE.W. of each test would be up to either 130 lb (59

kg) or 147.6 lb (67 kg). DET events will be hand-deployed from a boat

and exploded electronically by trained personnel.

MK-82 GPBs

The proposed action is an evaluation of the MK-82 GPBs to clear

anti-invasion beach obstacles and mines in the surf zone. The MK-82

GPBs to be tested consist of seven GPBs, each containing 192 lb (87.1

kg) of explosive for a total NE.W. of 1,344 lb (610 kg). The

configuration for testing will be a linear arrangement of seven bombs

spaced 24 ft (7.3 m) apart, located parallel to the shoreline in 6 ft

(1.8 m) of water.

Two separate deployments and firings are required to test this

configuration. All MK-82s will be buried vertically to approximately

one-half length (about 3 ft (0.9 m)) by jetting. The MK-82s will be

detonated using approximately 1/4 block of C-4 explosive paced into the

aft fuse well. The MK-82s will be detonated simultaneously in 6 ft (1.8

m) of water using remote detonators to detonate the C-4. Beach

obstacles (log posts, concrete cubes, and steel hedgehogs) and inert

mines will be placed around the bombs to serve as targets for bomb

fragments and blast.

MK-5 MCS

The MK-5 MCS consists of a 350-ft (106.7 m) continuous length

charge of composition C-4 explosive (with a distribution of 5 lb (2.3

kg) per linear foot and a pair of detonating cords (totaling 11 lb (5

kg). Total NE.W. of the system is 1,750 lb (794 kg). The MK-5 MCS would

be deployed in the surf zone about 550 ft (167.6 m) from shore by an

LCAC. Once fully deployed, it will then be detonated. Testing will take

place over a 3-day period. On the first day, there will be inert

firings of four MK5 systems. The second day will consist of one inert

firing and one live firing of a MK5 system. The third day will consist

of three separate live firings.

Comments and Responses

A notice of receipt of the application and proposed authorization

was published on October 13, 1998 (63 FR 54676), and a 30-day public

comment period was provided on the application and proposed

authorization. During the 30-day comment period, comments were received

from the Marine Mammal Commission (MMC), the Animal Protection

Institute (API), the Animal Rights Foundation of Florida, and two

private citizens.

Comment 1: Two commenters expressed concern that the underwater

explosions would affect the sensory perceptions of wild dolphins and

would inflict unnecessary stress and possible injury to the animals.

Response: While underwater explosions have the potential to harass,

injure, or kill marine mammals, the notice of proposed authorization

and the accompanying EAs provided information on mitigation measures

that would be undertaken by the applicant to ensure that no mortality

or serious injuries and few harassment takings would occur. These

measures are repeated later in this document.

Comment 2: Two individuals recommended that the tests be conducted

at an inland lake or pond on the Eglin property.

Response: As discussed in the draft EAs, while some testing can be

conducted in ponds, test ponds are unable to replicate the sea and surf

conditions, including wave action and berm formation, found in the

nearshore coastal waters. These conditions are necessary for successful

testing.

Comment 3: While recognizing that subsection 101(a)(5)(D) of the

MMPA authorizes the incidental harassment of marine mammals, the API

expressed concern over the numbers of dolphins that may be impacted by

the activity. They believe that the number of dolphins proposed for a

take by harassment should not be considered a small number.

Response: Interim regulations implementing subsection 101(a)(5)(D)

of the MMPA were issued on April 10, 1996 (61 FR 15884). These

regulations contain specific definitions to interpret Congressional

meaning of the terms ``small numbers'' and ``negligible impact.'' For

the purposes of this part, ``small numbers'' means a portion of a

marine mammal species or stock whose taking would have a negligible

impact on that species or stock. ``Negligible impact'' is 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. Because, due to mitigation measures required under IHA, no

marine mammals are likely to be killed or seriously injured by the

proposed activities, harassment takings are expected to be reduced to

the lowest level practicable, the number of authorized takings is

considered small, and the takings have no more than a negligible impact

on the affected species and stocks of marine mammals.

Comment 4: The API also believes that, because explosives have a

potential lethal impact on marine mammals, the application and

authorization would not fall under MMPA subsection 101(a)(5)(D).

Response: Depending upon the distance between the explosive and the

animal and the charge weight, explosives in the marine environment have

the potential to seriously injure or kill marine mammals. However, if

mitigating measures imposed on an applicant's activity through an IHA

reduce the impacts of the activity such that it is unlikely that

serious injury or mortality will result, then an IHA may be

appropriate. If however, upon review, an activity's mitigation measures

are not considered sufficient to eliminate mortality and serious

injury, NMFS will deny the application request and recommend the

applicant apply for a taking authorization under subsection

101(a)(5)(A) of the MMPA. An authorization under that section of the

MMPA allows for lethal takings incidental to an activity.

Comment 5: The API recommends that NMFS deny an IHA to the Air

Force to test underwater anti-mine devices in the waters off Eglin. One

individual recommended denial, partly because it would open the door to

future testing that could be harmful to marine life.

Response: NMFS would like to clarify that NMFS' responsibility in

this action is limited to the issuance or denial of an authorization

for the short-term, incidental harassment of a small number of marine

mammals by the Air Force while conducting explosive testing of obstacle

and mine clearance systems at Eglin. NMFS does not authorize the

activity itself, as such authorization is provided by the U.S.

Department of Defense and is not within the jurisdiction of the

Secretary of

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Commerce. As provided by subsection 101(a)(5)(D) of the MMPA, unless

NMFS finds that the activity will result in a taking of marine mammals

that is either not small or results in more than a negligible impact,

the authorization is warranted. Authorizations to take marine mammals

incidental to detonating explosives in the marine environment have been

issued previously.

Comment 6: Concerned that there is the possibility that a manatee

could be within the zone of influence of the detonations, the MMC

recommended the Air Force consult with the U.S. Fish and Wildlife

Service (USFWS) under section 7 of the Endangered Species Act (ESA).

Response: The Air Force consulted with the USFWS under section 7 of

the ESA on this activity. This consultation was principally for the

Gulf sturgeon, a listed fish species. Neither agency indicated that

manatees inhabit the test area during the time of the year that tests

are authorized.

Description of Habitat and Marine Mammals Affected by the Activity

A description of the project area ecosystem in the eastern Gulf of

Mexico (GOM) can be found in the application and in the associated

draft EAs and needs not be repeated here.

Marine Mammals

Although approximately 27 species of marine mammals (whales,

dolphins, and porpoises) reside in or pass through the northeastern

GOM, the only species of marine mammals that are likely to be impacted

by the activities proposed for the shallow coastal waters off SRI are

the bottlenose dolphin (Tursiops truncatus) and the Atlantic spotted

dolphin (Stenella frontalis). Information on these two species may be

found in the application and in the supporting EAs for these projects.

Additional information on these and other species of marine mammals in

the GOM can be found in Blaylock et al. (1995) and Waring et al.

(1997). Please refer to those documents for information on the biology,

distribution, and abundance of these species.

Potential Effects of Explosives on Marine Mammals

Potential impacts to those marine mammal species known to occur in

the SRI area from explosives include both lethal and non-lethal injury,

as well as incidental harassment. The pressure wave from the explosive

can impact air cavities, such as lungs and intestines. Extensive

hemorrhaging into the lungs due to underwater shock waves may cause

death to a marine mammal through suffocation (Hill, 1978). Other common

injuries which may result in mortality include circulatory failure,

broncho-pneumonia in damaged lungs, or peritonitis resulting from

perforations of the intestinal wall (Hill, 1978). Because impulse

levels sufficient to cause lethal injury increase with increased mammal

mass (Yelverton et al., 1973), conservative criteria are based on the

lowest possible affected mammalian weight (e.g., an infant dolphin).

Extensive lung hemorrhage is an injury which would be debilitating, and

not all animals would be expected to survive (1- percent mortality is

predicted at the onset level). As the severity of extensive lung

hemorrhage increases beyond the onset level, gastro-intestinal tract

injuries can increase significantly. The expected mortality level

associated with these combined severe injuries would be significantly

higher than 1 percent (U.S. Navy, 1998).

Non-lethal injuries involve slight lung hemorrhage and tympanic

membrane (TM) rupture from which the mammal is expected to recover

(Yelverton et al., 1973; Richmond et al., 1973). Eardrum damage

criteria are based upon a limited number of small charge tests

(Yelverton et al., 1973; Richmond et al., 1973). Ranges for percent TM

rupture incurred by underwater explosives can be calculated by a

conservative TM damage model (U.S. Navy, 1996). General criteria for TM

damage have been reported to occur at impulse levels down to 20 psi-

msec (Yelverton et al., 1973).

Because eardrum (e.g., TM) rupture, rather than slight lung

hemorrhage, usually occurs at lower impulse levels, TM rupture is used

by NMFS and others to conservatively define the non-lethal injury zone.

A maximum impulse of 10 psi-msec is often considered to define the non-

lethal injury zone, where a very low incidence of blast injuries are

likely to occur (Yelverton et al., 1973). A level of pressure impulse

at which marine mammals are not expected to experience non-lethal

injury (nor instantaneous mortality or lethal injury) is reported to be

5 psi-msec (Yelverton et al., 1973). This is the impulse level adopted

by the Air Force to designate no injurious takings by this activity.

In addition to lethal, serious, and non-serious injury, harassment

of marine mammals may occur as a result of non-injurious physiological

responses to an explosion-generated shockwave and its acoustic

signature. Based upon information provided in the SEAWOLF shock trial

final environmental impact statement (U.S. Navy, 1998), a dual

criterion for marine mammal acoustic harassment has been developed for

explosive-generated signals: (1) An energy-based temporary threshold

shift (TTS) injury criterion of 182 dB re 1 uPa2 -sec

derived from experiments with bottlenose dolphins (Ridgway et al.,

1997), and (2) a 12- lbs/in2 (psi) peak pressure cited by

Ketten (1995) as associated with a ``safe outer limit (for the 10,000

lb charge for minimal, recoverable auditory trauma'' (i.e., TTS)). For

this activity, noise levels that fall between the 5 psi-msec and out to

a transmission distance where a noise level of 180 dB re 1

uPa2 -sec (Air Force, 1998) will be considered to fall

within the incidental harassment zone.

The potential impact to Atlantic bottlenose dolphins and the

Atlantic spotted dolphins, the two species that may potentially be

affected, was evaluated using modeling on the effects of underwater

explosions resulting from each of the test systems described previously

(see application). Based upon data provided in Tables 5.2 and 5.3 in

the application, the maximum number of Atlantic bottlenose dolphins

potentially injured from all tests ranges from 4 to 13. The maximum

number of Atlantic spotted dolphins potentially injured from all tests

combined is less than 1. These are the maximum injury levels without

implementation of mitigation.

The estimated total numbers of bottlenose dolphins and spotted

dolphins potentially exposed to takes by harassment are 33 and 1,

respectively. The total number of bottlenose dolphins potentially

exposed to noise from the source of the noise to 180 dB re 1

uPa2 -sec ranges from 4 to 15 for the MK-82 GPB tests, 1 to

3 for the MK5 MCS tests, 1 to 2 for the combined SABRE tests, and 4 to

13 for all DET array tests combined. However, mitigation is expected to

obviate any injury to marine mammals.

Mitigation

There are two forms of mitigation: (1) Natural, as provided by the

environment and (2) human, designed to protect marine mammals to the

greatest extent practicable.

Natural mitigation: Physical characteristics of the proposed test

area and test methods will ameliorate the underwater shock wave. Tests

will be conducted in approximately 3 to 10 ft (0.9 to 3.0 m) of water.

At this shallow depth, some protection of the energy from the

detonations will be directed through the surface of the water rather

than transmitted through the water. Another consequence of the shallow,

as opposed to the deep water detonation depth, is that bubble pulse is

not

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significant and there will be far less energy in any oscillations.

Additionally, these tests will be conducted inside the offshore bar at

the SRI site. The offshore bar ameliorates the transmission of the

underwater portion of the shock wave. Also, MK-82 GPBs will be buried

in bottom sands to approximately their center of gravity (3 ft (0.9 m),

a factor expected to mitigate the transmission of the shock wave as the

detonations will be directed downwards.

Human mitigation: Eglin has established safety zones to prevent

marine mammal injury for each test. These safety zones are: 0.75 km

(0.47 mi) for SABRE-22, 1.0 km (0.62 mi) for SABRE-23, 1.0 km (0.62 mi)

for DET, 6.0 km (3.73 mi) for MK-82 GPB, and 0.5 km (0.31 mi) for MK-5

MCS.

Eglin has proposed that base personnel conduct a 30-minute pre-

detonation aerial monitoring survey immediately prior to each test to

ensure no marine mammals are within each test area's designated safety

zone. With water depths less than 18 m (59 ft), low turbidity, and

white sand bottom, exceptional marine mammal visibility is ensured.

Aerial surveys will be conducted at approximately 100 ft (30.5 m)

elevation.

In order to ensure adequate visibility for locating marine mammals

(and sea turtles), no tests will take place if sea state conditions are

greater than category 3 and water clarity is not adequate for

conducting surveys. No tests will take place if marine mammals or sea

turtles are sighted within the safety zone.

Monitoring

In addition to pre-detonation monitoring mentioned previously,

Eglin will conduct aerial surveys immediately following each detonation

event. The post-test monitoring will be conducted in a similar manner

to the pre-test monitoring, except that observation personnel will be

focusing on locating any injured marine mammals. If any injured marine

mammals are observed during post-test monitoring, subsequent

detonations will be postponed, and the local stranding network

notified. The project will be required to be reviewed by Air Force and

NMFS personnel prior to conducting any additional tests.

Reporting

Any takes of marine mammals other than those authorized by the IHA

will be reported to the Regional Administrator, NMFS, by the next

working day. A draft final report of the entire test results and marine

mammal observations for pre- and post-detonation monitoring will be

submitted to NMFS within 90 days after completion of the last test.

Unless notified by NMFS to the contrary, that draft final report will

be considered the final report under the IHA.

National Environmental Policy Act (NEPA)

As part of its request for a small take authorization, the Air

Force prepared two EAs, one for SABRE and DET and a second document for

the MK-82/MK-5 systems. These EAs, which supplement information

contained in the application, are necessary for determining whether the

activities proposed for receiving small take authorizations are having

a negligible impact on affected marine mammal stocks. NMFS has reviewed

the EAs and concurs with the findings. As a result, NMFS finds that it

is unnecessary to prepare its own NEPA documentation and hereby adopts

the Air Force EAs as its own, as provided by 40 CFR 1506.3. NMFS finds

that the issuance of an IHA to the Air Force will not result in a

signficant environmental impact on the human environment and that it is

unnecessary to either prepare its own NEPA documentation or to

recirculate the Air Force EAs for additional comments.

Consultation

On October 15, 1998, NMFS completed consultation with the Air Force

under section 7 of the ESA. The finding of that consultation was that

the proposed testing activity is not likely to adversely affect

endangered or threatened species of whales or sea turtles, if the

conservation and mitigation measures specified in the Biological

Assessment prepared by the Air Force are undertaken. NMFS concludes,

therefore, that the issuance of an IHA to the Air Force to take small

numbers of bottlenose dolphins, spotted dolphins and possibly other

cetacean species by harassment incidental to explosive testing at Eglin

is not likely to adversely affect endangered or threatened species of

whales or sea turtles.

Conclusions

NMFS has determined that the short-term impact of incidentally

taking small numbers of bottlenose dolphins, spotted dolphins, and

possibly other cetacean species by harassment and non-serious injury

incidental to explosive testing of obstacle and mine clearance systems

at Eglin, as described previously in this document, will result, at

worst, in the brief harassment of these species and possibly in a

temporary behavioral modification. While behavioral modifications may

be made by these species to avoid the resultant acoustic disturbance,

this action is expected to have a negligible impact on both individual

animals and the stocks of these mammals. In addition, no take by injury

and/or death is anticipated, and harassment takes will be at the lowest

level practicable due to incorporation of the mitigation measures

mentioned above.

Since NMFS is assured that the taking would not result in more than

the incidental harassment (as defined by the MMPA) of small numbers of

bottlenose dolphins, spotted dolphins and possibly other cetacean

species and would result in the least practicable impact on the stocks,

NMFS has determined that the requirements of subsection 101(a)(5)(D)

have been met and the authorization can be issued.

Authorization

For the above reasons, NMFS has issued an IHA to the Air Force for

the incidental harassment and non-serious injury of a small number of

bottlenose dolphins, spotted dolphins, and possibly other cetacean

species. NMFS has determined that, provided the mitigation, monitoring,

and reporting requirements described in the authorization are

undertaken the short-term impact of explosives testing for obstacle and

mine clearance systems at Eglin has the potential to result in no more

than a negligible impact on affected marine mammal stocks.

Dated: December 3, 1998.

Patricia A. Montanio,

Deputy Director, Office of Protected Resources, National Marine

Fisheries Service.

[FR Doc. 98-32534 Filed 12-7-98; 8:45 am]

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