Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to the Explosive Removal of Offshore Structures in the Gulf of Mexico, 17790-17804 [06-3327]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 71, Number 67 (Friday, April 7, 2006)]
[Proposed Rules]
[Pages 17790-17804]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 06-3327]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 216

[Docket No. 060314068-6068-01; I.D. 030905A]
RIN 0648-AT79


Taking and Importing Marine Mammals; Taking Marine Mammals 
Incidental to the Explosive Removal of Offshore Structures in the Gulf 
of Mexico

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

ACTION: Proposed rule.

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SUMMARY: NMFS has received a request from the Minerals Management 
Service (MMS), for authorization to ``take'' by harassment small 
numbers of marine mammals incidental to explosive severance activities 
at offshore oil and gas structures in the Gulf of Mexico (GOM) outer 
continental shelf (OCS). By this document, NMFS is proposing 
regulations to govern that take. In order to issue Letters of 
Authorization (LOAs) and final regulations governing the take, NMFS 
must determine that the total taking will have a negligible impact on 
the affected species and stocks of marine mammals, will be at the 
lowest level practicable, and will not have an unmitigable adverse 
impact on the availability of the species or stock(s) for subsistence 
uses. NMFS invites comment on the application and the proposed rule.

DATES: Comments and information must be postmarked no later than May 
22, 2006.

ADDRESSES: You may submit comments on the application and proposed 
rule, using the identifier 030905A, by any of the following methods:
     E-mail: PR1.030905A@noaa.gov. Please include the 
identifier 030905A in the subject line of the message. Comments sent 
via e-mail, including all attachments, must not exceed a 10-megabyte 
file size.
     Federal e-Rulemaking Portal: https://www.regulations.gov. 
Follow the instructions for submitting comments.
     Hand-delivery or mailing of paper, disk, or CD-ROM 
comments should be addressed to: Stephen L. Leathery, Chief, Permits, 
Conservation and Education Division, Office of Protected Resources, 
National Marine Fisheries Service, 1315 East-West Highway, Silver 
Spring, MD 20910.
    A copy of the MMS application, under section 101(a)(5)(A) of the 
Marine Mammal Protection Act (MMPA), containing a list of references 
used in this document may be obtained by writing to this address, by 
telephoning the contact listed under FOR FURTHER INFORMATION CONTACT, 
or at: https://www.nmfs.noaa.gov/pr/permits/incidental.htm#iha. A copy 
of MMS' Programmatic Environmental Assessment (PEA) is available on-
line at: https://www.gomr.mms.gov/homepg/regulate/environ/nepa/2005-
013.pdf. Documents cited in this proposed rule, that are not available 
through standard public library access, may be viewed, by appointment, 
during regular business hours at the mailing address previously 
specified. To help us process and review comments more efficiently, 
please use only one method for commenting.
    Comments regarding the burden-hour estimate or any other aspect of 
the collection of information requirement contained in this proposed 
rule should be sent to NMFS via the means stated above, and to the 
Office of Information and Regulatory Affairs, Office of Management and 
Budget (OMB), Attention: NOAA Desk Officer, Washington, DC 20503, 
David--Rostker@eap.omb.gov.

FOR FURTHER INFORMATION CONTACT: Kenneth R. Hollingshead, NMFS, at 301-
713-2055, ext 128 or Ken.Hollingshead@noaa.gov.

SUPPLEMENTARY INFORMATION:

Background

    Sections 101(a)(5)(A) and 101(a)(5)(D) of the MMPA (16 U.S.C. 1361 
et seq.) direct the Secretary of Commerce (Secretary) to allow, upon 
request, the incidental, but not intentional taking of small numbers of 
marine mammals by U.S. citizens who engage in a specified activity 
(other than commercial fishing) within a specified geographical region 
if certain findings are made and regulations are issued.
    An authorization will 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 if the permissible methods of taking 
and requirements pertaining to the mitigation, monitoring and reporting 
of such takings 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.''

Summary of Request

    On February 28, 2005, NMFS received an application from MMS (MMS, 
2005a) requesting, on behalf of the offshore oil and gas industry, 
authorization under section 101(a)(5)(A) of the MMPA to take marine 
mammals by harassment incidental to explosive severance activities at 
offshore oil and gas structures in the GOM OCS. Except for certain 
categories of activities not pertinent here, 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].

Description of the Activity

    During exploration, development, and production operations for 
mineral extraction in the GOM OCS, the seafloor around activity areas 
becomes the repository of temporary and permanent equipment and 
structures. In compliance with OCS Lands Act (OCSLA) regulations and 
MMS guidelines, operators are required to remove or ``decommission'' 
seafloor obstructions from their leases within one year of lease 
termination or after a structure has been deemed obsolete or unusable. 
To accomplish these removals, a host of activities is required to (1) 
mobilize necessary equipment and service vessels, (2) prepare the 
decommissioning targets (e.g., piles, jackets, conductors, bracings, 
wells, pipelines, etc.), (3) sever the target from the seabed and/or 
sever it into manageable components, (4) salvage the severed 
portion(s), and (5) conduct final site-clearance verification work.
    There are two primary methodologies used in the GOM for cutting 
decommissioning targets; nonexplosive and explosive severance. 
Nonexplosive methods include abrasive cutters (sand and abrasive-water 
jets), mechanical cutters (e.g., carbide or rotary), diamond wire 
cutting devices, and cutting facilitated by commercial divers using 
arc/gas torches. Though relatively time-consuming and potentially 
harmful to

[[Page 17791]]

human health and safety (primarily for diver severances), nonexplosive-
severance activities have little or no impact on the marine environment 
and would not result in an incidental take of marine mammals (MMS, 
2005b (PEA)). A description of non-explosive severing tools and methods 
can be found in MMS, 2005a and MMS, 2005b (section 1.4.7.1)(see 
ADDRESSES).
    Explosive-severance activities use specialized charges to achieve 
target severance. Severance charges can be deployed on multiple targets 
and detonated nearly-simultaneously (i.e., staggered at an interval of 
900 msec) effecting rapid severances. Coupled with safe-handling 
practices, the reduced ``exposure time'' and omission of diver cutting 
also makes explosive severance safer for offshore workers. However, 
since the underwater detonation of cutting charges generates damaging 
pressure waves and acoustic energy, explosive-severance activities have 
the potential to result in an incidental take of nearby marine mammals. 
For this reason, MMS has requested an incidental take authorization 
governing explosive-severance activities that could be conducted under 
OCSLA structure decommissionings.
    Decommissioning operations conducted under OCSLA authority can 
occur on any day of a given year. Operators often schedule most of 
their decommissionings from June to December (approximately 80 percent) 
to take advantage of the often calm seas and good weather and the time 
period when structure installations tend to decrease since both 
commissioning and decommissioning operations compete for the same 
management groups, equipment, vessels, and labor force (TSB/CES/LSU, 
2004).
    Depending upon the target, a complete decommissioning operation may 
span several days or weeks; however, the explosive-severance activity 
or ``detonation event'' for most removal targets (even those with 
multiple severances) last for only several seconds because of charge 
staggering. For complex targets or in instances where the initial 
explosive-severance attempts are unsuccessful, more than one detonation 
event may be necessary per decommissioning operation. Even though hours 
or days may pass to allow for necessary mitigation measures and 
redeployment of new charges, each detonation event would similarly last 
only for a few seconds.
    During the 10 year period from 1994-2003, there were an average of 
156 platform decommissionings per year, with over 60 percent involving 
explosive-severance activities (see Table 4 in MMS, 2005a). In addition 
to historical activity averages, many of the older, nominally-producing 
structures in the mature GOM oil fields are nearing decommissioning 
age; this will result in an increase in removal operations in future 
years. Despite advancements in nonexplosive-severance methods and the 
additional requisite marine protected species mitigations, MMS expects 
explosive-severance activities to continue in at least 63 percent of 
all platform removals for the foreseeable future. (See Appendix A of 
MMS, 2005b) for additional forecasting information).
    In addition to platform removals, based upon a review of the 
historical trends, industry projections, and recent forecast modeling, 
MMS estimates that between 170 and 273 explosive well-severance 
activities would occur annually over the next 5 years (see Table 7 in 
MMS, 2005a).

Comments and Responses

    On August 24, 2005 (70 FR 49568), NMFS published a notice of 
receipt of MMS' application for LOAs and requested comments, 
information and suggestions concerning the request and the structure 
and content of regulations to govern the take. During the 30-day public 
comment period, NMFS received one set of comments.
    The Marine Mammal Commission recommended that NMFS initiate the 
proposed rulemaking provided it is satisfied that the planned marine 
mammal and related monitoring programs will be adequate to verify how 
and over what distances marine mammals may be affected, that only small 
numbers of marine mammals will be taken, and that the cumulative 
impacts on the affected species and stocks will be negligible.
    As described in detail in this document, all detonations are 
monitored by trained biological observers in aircraft and watercraft 
with mitigation and monitoring established commensurate with the type 
of detonation and the charge weight. Similar extensive monitoring 
programs, conducted by trained biological observers, including post-
blast monitoring, have not indicated that any marine mammals have been 
seriously injured or killed by explosive severance activities.

Description of Habitat and Marine Mammals Affected by the Activity

    The proposed explosive severance activities could occur in all 
water depths of the offshore areas designated by MMS as the GOM Central 
and Western Planning Areas (CPA and WPA) and a portion of the Eastern 
Planning Area (EPA) offered under Lease Sale 181/189 (see Figure 2 or 3 
in MMS, 2005a). Water depths in the areas of the proposed action range 
from 4 to 3,400 m (13-11,155 ft), with the majority of existing 
facilities and wells found within the CPA, concentrated on the upper 
shelf waters (less than 200 m (656 ft) water depth) off of Louisiana. A 
detailed description of the northern GOM area and its associated marine 
mammals can be found in the MMS application and PEA and in a number of 
documents referenced in the application. Detailed information on the 
marine mammals in the GOM can also be found in the NMFS status of 
stocks reports (Waring et al., 2004) which are available for 
downloading or reading at: https://www.nefsc.noaa.gov/nefsc/
publications/tm/tm182/.
    A total of 28 cetacean species and one species of sirenian (West 
Indian manatee) are known to occur in the GOM. These species are the 
sperm whale, pygmy sperm whale, dwarf sperm whale, Cuvier's beaked 
whale, Sowerby's beaked whale (extralimital), Gervais' beaked whale, 
Blainville's beaked whale, rough-toothed dolphin, bottlenose dolphin, 
pantropical spotted dolphin, Atlantic spotted dolphin, spinner dolphin, 
Clymene dolphin, striped dolphin, Fraser's dolphin, Risso's dolphin, 
melon-headed whale, pygmy killer whale, false killer whale, killer 
whale, short-finned pilot whale, North Atlantic right whale 
(extralimital), humpback whale (rare), minke whale (rare), Bryde's 
whale, sei whale (rare), fin whale (rare), and the blue whale 
(extralimital).
    A description of the status, distribution, and seasonal 
distribution of the affected species and stocks of marine mammals that 
might be affected by explosive severance activities is provided in MMS, 
2005a.

Potential Impacts to Marine Mammals

    Underwater explosions are the strongest manmade point sources of 
sound in the sea (Richardson et al., 1995). The underwater pressure 
signature of a detonating explosion is composed of an initial shock 
wave, followed by a succession of oscillating bubble pulses (if the 
explosion is deep enough not to vent through the surface) (Richardson 
et al., 1995). The shock wave is a compression wave that expands 
radially out from the detonation point of an explosion. Although the 
wave is initially supersonic, it is quickly reduced to a normal 
acoustic wave. The broadband

[[Page 17792]]

source levels of charges weighing 0.5-20 kg (1.1-44 lb) are in the 
range of 267-280 dB re 1 microPa (at a nominal 1-m distance), with 
dominant frequencies below 50 Hz (Richardson et al., 1995; CSA, 2004). 
The following sections discuss the potential impacts of underwater 
explosions on marine mammals, including mortality, injury, hearing 
effects, and behavioral effects.

Mortality or Injury

    It has been demonstrated that nearby underwater blasts can injure 
or kill marine mammals (Richardson et al., 1995). Injuries from high-
velocity underwater explosions result from two factors: (1) the very 
rapid rise time of the shock wave; and (2) the negative pressure wave 
generated by the collapsing bubble, which is followed by a series of 
decreasing positive and negative pressure pulses (CSA, 2004). The 
extent of injury largely depends on the intensity of the shock wave at 
the receiver (marine mammal) and the size and depth of the animal 
(Yelverton et al., 1973; Craig, 2001).
    The greatest damage occurs at boundaries between tissues of 
different densities because different velocities are imparted that can 
lead to their physical disruption; effects are generally greatest at 
the gas-liquid interface (Landsberg, 2000; CSA, 2004). Gas-containing 
organs, especially the lungs and gastrointestinal tract, are the most 
susceptible to this type of damage. Lung injuries (including 
lacerations and the rupture of the alveoli and blood vessels) can lead 
to hemorrhage, air embolisms, and breathing difficulties. The lungs and 
other gas-containing organs (nasal sacs, larynx, pharynx, and trachea) 
may also be damaged by compression/expansion caused by oscillations of 
the blast gas bubble (Reidenberg and Laitman, 2003). Intestinal walls 
can bruise or rupture, which may lead to hemorrhage and the release of 
gut contents. Less severe injuries include contusions, slight 
hemorrhaging, and petechia (Yelverton et al., 1973; CSA, 2004). Ears 
are the organs most sensitive to pressure and, therefore, to injury 
(Ketten, 2000; CSA, 2004). Severe damage to the ears can include 
rupture of the tympanic membrane, fracture of the ossicles, cochlear 
damage, hemorrhage, and cerebrospinal fluid leakage into the middle 
ear. By themselves, tympanic membrane rupture and blood in the middle 
ear can result in partial, permanent hearing loss. Permanent hearing 
loss can also occur when the hair cells are damaged by loud noises 
(ranging from single, very loud events to chronic exposure).

Hearing Effects

    Mammalian hearing functions over a wide range of sound intensities, 
or loudness. The sensation of loudness increases approximately as the 
logarithm of sound intensity (Richardson and Malme, 1993). Sound 
intensity is usually expressed in decibels (dB), units for expressing 
the relative intensity of sounds on a logarithmic scale. Because sound 
pressure is easier to measure than intensity and intensity is 
proportional to the square of sound pressure, sound pressure level is 
usually reported in units of decibels relative to a standard reference 
pressure. Based on the information presented in Richardson et al. 
(1995), the possible behavioral effects of noise from underwater 
explosions on marine mammals may be categorized as follows:
    1. The noise may be too weak to be heard at the location of the 
animal (i.e., below the local ambient noise level, below the hearing 
threshold of the animal at the relevant frequencies, or both);
    2. The noise may be audible, but not loud enough to elicit an overt 
behavioral reaction;
    3. The noise may elicit behavioral reactions, which may vary from 
subtle effects on respiration or other behaviors (detectable only 
statistically) to active avoidance behavior;
    4. With repeated exposure, habituation (diminishing responsiveness) 
to the noise may occur. Continued disturbance effects are most likely 
with sounds that are highly variable in their characteristics, 
unpredictable in occurrence, and associated with situations perceived 
by the animal as threatening;
    5. Any anthropogenic noise that is strong enough to be heard has 
the potential to reduce (mask) the ability of a marine mammal to hear 
natural sounds at similar frequencies, including calls from 
conspecifics, and underwater environmental sounds such as surf noise.
    6. If mammals remain in an area because it is important for 
feeding, breeding or some other biologically important purpose even 
though there is chronic exposure to noise, it is possible that there 
could be noise-induced physiological stress; this might in turn have 
negative effects on the well-being or reproduction of the animals 
involved; and
    7. Very strong sounds have the potential to cause temporary or 
permanent reduction in hearing sensitivity. In terrestrial mammals, and 
presumably marine mammals, received sound levels must far exceed the 
animal's hearing threshold for there to be any temporary threshold 
shift (TTS) in its hearing ability. For transient sounds, the sound 
level necessary to cause TTS is inversely related to the duration of 
the sound exposure. Received sound levels must be even higher for there 
to be risk of permanent hearing impairment. In addition, intense 
acoustic or explosive events may cause trauma to tissues associated 
with organs vital for hearing, sound production, respiration and other 
functions. This trauma may include minor to severe hemorrhage.

TTS

    The mildest form of hearing damage, TTS, is defined as the 
temporary elevation of the minimum hearing sensitivity threshold at 
particular frequency(s) (Kryter, 1985; CSA, 2004). TTS may last from 
minutes to days. Although few data exist on the effects of underwater 
sound on marine mammal hearing, in terrestrial mammals, and presumably 
in marine mammals, received levels must exceed an animal's hearing 
threshold (i.e., maximum sensitivity) for TTS to occur (Richardson et 
al., 1995; Kastak et al., 1999; Wartzok and Ketten, 1999).
    Most studies involving marine mammals have measured exposure to 
noise in terms of sound pressure level (SPL), measured in dBrms or 
dBpeak pressure re 1 microPa. Exposure to underwater sound can also be 
expressed in terms of energy, also called sound exposure level (SEL), 
or acoustic energy (measured in dB re 1 microPa\2\-s), which, unlike 
SPL measurements, considers both intensity and duration of the sound. 
If TTS is defined as a measurable threshold shift of 6 dB or more 
(Finneran et al., 2000, 2002), then based on experiments with white 
whales and bottlenose dolphins, the onset of TTS was associated with an 
energy level of about 184 dB re 1 microPa\2\-s (CSA, 2004). However, 
the data are very limited, and Finneran (2003) has noted that they 
should be interpreted with caution.

Permanent Threshold Shift (PTS)

    PTS is a permanent decrease in the functional sensitivity of an 
animal's hearing system at some or all frequencies (CSA, 2004). The 
principal factors involved in determining whether PTS will occur 
include sound impulse duration, peak amplitude, and rise time. The 
criteria are location and species-specific (Ketten, 1995) and are also 
influenced by the health of the receiver's ear.

[[Page 17793]]

    At least in terrestrial animals, it has been demonstrated that the 
received level from a single exposure must be far above the TTS 
threshold for there to be a risk of PTS (Kryter, 1985, Richardson et 
al., 1995; CSA, 2004). Sound signals with sharp rise times (e.g., from 
explosions) produce PTS at lower intensities than do other types of 
sound (Gisiner, 1998; CSA, 2004).
    For explosives, Ketten (1995) estimated that greater than 50-
percent PTS would occur at peak pressures of 237-248 dB re 1 microPa 
and that TTS would occur at peak pressures of 211-220 dB re 1 microPa. 
The ``safe'' peak pressure level to avoid physical injury recommended 
by Ketten (1995) is 100 psi (237 dB re 1 microPa, or about 212 dB re 1 
microPa2-s). PTS is assumed to occur at received levels 30 dB above 
TTS-inducing levels. Studies have shown that injuries at this level 
involve the loss of sensory hair cells (Ahroon et al., 1996; CSA, 
2004).

Behavioral Effects

    Behavioral reactions of marine mammals to sounds such as those 
produced by underwater explosives are difficult to predict. Whether and 
how an animal reacts to a given sound depends on factors such as the 
species, hearing acuity, state of maturity, experience, current 
activity, reproductive state, time of day, and weather.
    Richardson et al. (1995) summarized available information on the 
reported behavioral reactions of marine mammals to underwater 
explosions. Observations following the use of seal bombs as scare 
charges indicate that pinnipeds rapidly habituate to and, in general, 
appear quite tolerant of, noise pulses from explosives. Klima et al. 
(1988) reported that small charges were not consistently effective in 
moving bottlenose dolphins away from blast sites in the GOM. Since 
dolphins may be attracted to the fish killed by such a charge, rather 
than repelled, scare charges are not used in the GOM platform removal 
program (G. Gitschlag, personal communication, in Richardson et al., 
1995).
    There are few data on the reactions of baleen whales to underwater 
explosions. Gray whales were apparently unaffected by 9- to 36-kg (20- 
to 97-lb) charges used for seismic exploration (Fitch and Young, 1948). 
However, Gilmore (1978) felt that similar underwater blasts within a 
few kilometers of the gray whale migration corridor did ``sometimes'' 
interrupt migration.
    Humpback whales have generally not been observed to exhibit 
behavioral reactions (including vocal ones) to explosions, even when 
close enough to suffer injury (hearing or other) (Payne and McVay, 
1971; Ketten et al., 1993; Lien et al., 1993; Ketten, 1995; Todd et 
al., 1996). In Newfoundland, humpbacks displayed no overt reactions 
within about 2 km of 200- to 2,000-kg explosions. Whether habituation 
and/or hearing damage occurred was unknown, but at least two whales 
were injured (and probably killed) (Ketten et al., 1993). Other 
humpback whales in Newfoundland, foraging in an area of explosive 
activity, showed little behavioral reaction to the detonations in terms 
of decreased residency, overall movements, or general behavior, 
although orientation ability appeared to be affected (Todd et al., 
1996). Todd et al. (1996) suggested caution in interpretation of the 
lack of visible reactions as indication that whales are not affected or 
harmed by an intense acoustic stimulus; both long- and short-term 
behavior as well as anatomical evidence should be examined. The 
researchers interpreted increased entrapment rate of humpback whales in 
nets as the whales being influenced by the long-term effects of 
exposure to deleterious levels of sound.
    As mentioned previously, Finneran et al. (2000) exposed captive 
bottlenose dolphins and belugas to single, simulated sounds of distant 
explosions. The broad-band received levels were 155-206 dB; pulse 
durations were 5.4-13 ms. This was equivalent to a maximum spectral 
density of 102-142 dB re 1 microPa\2\/Hz at a 6.1 Hz bandwidth. 
Although pulse durations differed, the source levels required to induce 
a behavioral response to the introduced sounds were similar to those 
found by Ridgway et al. (1997) and Schlundt et al. (2000).

Estimates of Take by Harassment During Explosive Severance Activities 
in the GOM

    The MMS has requested NMFS to issue authorizations, under section 
101(a)(5)(A) of the MMPA, to cover any potential take by Level A or 
Level B harassment for the 28 species of cetaceans listed previously in 
this document, incidental to the oil and gas industry conducting 
explosive-severance operations regulated by the MMS. Explosive 
severance operations have the potential to take marine mammals by 
contact with shock wave and acoustic energy released from underwater 
detonations and the resultant injury, hearing damage, and behavioral 
effects. For this activity, MMS has adopted, without modification, 
NMFS' take thresholds and criteria for explosives used in the 
incidental take authorization for shock trials for the U.S. Navy's 
Winston Churchill (Navy, 2001). While these criteria remain a subject 
for future discussion and revision (see 69 FR 21816, April 22, 2004, 
and 70 FR 48675, August 19, 2005), the Winston Churchill criteria 
(i.e., 12 pounds/in\2\ (psi) peak-pressure and 182 dB (re 1 microPa\2\-
sec)) have been used by MMS for this activity because these criteria 
remain conservative. For example, Finneran et al. (2003) did not find 
masked TTS in the single bottlenose dolphin tested at the highest 
exposure conditions: peak pressure of 207 kPa (30 psi), 228 dB re 1 
microPa pk-pk pressure, and 188 dB re 1 microPa\2\-s total energy flux.
    The criteria for nonlethal, injurious impacts (Level A harassment) 
are currently defined as the incidence of 50-percent tympanic-membrane 
(TM) rupture and the onset of slight lung hemorrhage for a 12.2-kg (27 
lb) dolphin calf. Level A harassment take is assumed to occur:
    1. At an energy flux density value of 1.17 in-lb/in\2\ (which is 
about 205 dB re 1 microPa2-s); and
    2. If the peak pressure exceeds 100 psi for an explosive source; 
i.e., the ``safe'' peak pressure level to avoid physical injury 
recommended by Ketten (1995).
    The horizontal distance from the explosive to each threshold is 
determined and the maximum distance at which either is exceeded is 
considered to be the distance at which Level A harassment would occur 
(U.S. Dept. Navy, 2001).
    NMFS recognizes two levels of noninjurious acoustic impacts (Level 
B harassment). One criterion for Level B harassment is defined by the 
onset of TTS. Two thresholds are applied. TTS is assumed to be induced:
    1. At received energies greater than 182 dB re 1 microPa\2\-s 
within any 1/3-octave band; and
    2. If, for an explosive source, the peak pressure at the animal 
exceeds 12 psi.
    As with Level A harassment, the horizontal distance to each 
threshold has been determined and the maximum distance at which either 
is exceeded is considered the distance at which Level B harassment 
(TTS) would occur (Navy, 1998 and 2001; CSA, 2004). These distances 
have been used for estimating conservative zones of impact.
    ``Sub-TTS'' behavioral effects may also be considered to constitute 
a take by Level B harassment if a marine mammal reacts to an activity 
in a manner that would affect some behavioral pattern in a biologically 
significant way. Single, minor reactions (such as startle or ``heads-
up'' alert displays, short-term changes in breathing rates, or modified 
single dive

[[Page 17794]]

sequences) that have no biological context would not qualify as takes 
(66 FR 22450, May 4, 2001). This would include minor or momentary 
strictly behavioral responses to single events such as underwater 
explosions. Since explosive severance activities result in single, 
almost instantaneous detonations, with no repetitive detonations, NMFS 
does not believe that marine mammals would be subject to behavioral 
harassment other than behavioral modifications potentially incurred as 
a result of TTS.
    In order to obtain potential incidental take numbers for explosive 
severance activities, fundamental modeling components require: (1) 
predictive modeling of detonation pressure/energy propagation, (2) 
propagation model verification and utilization, (3) predictive modeling 
of marine mammal take estimates, and (4) take-estimate calculation. 
These models and the calculations resulting from those models are 
explained in detail in MMS, 2005a and MMS, 2005b.
    Based on MMS calculations for all explosive-severance monitoring 
scenarios, Level A harassment takes would be limited to less than one 
bottlenose dolphin annually and between three and five bottlenose 
dolphins, one Atlantic spotted, and one pantropical spotted dolphin 
over the five-year period of these proposed regulations.
    Based on MMS calculations for all explosive-severance scenarios, 
annual Level B harassment takes would be limited to 148-227 bottlenose 
dolphins, 35-65 Atlantic spotted dolphins, 33-77 pantropical spotted 
dolphins, 11-27 Clymene dolphins, 8-12 rough-toothed dolphins, 6-14 
striped dolphins, 6-15 melon-headed whales, 4-10 pilot whales, 2-5 
spinner dolphins, 1-3 Risso's dolphins, and 1-2 sperm whales. It should 
be noted that Level A and Level B harassment estimates are made without 
consideration of the implementation of mitigation measures to protect 
marine mammals, so actual harassment numbers would likely be lower. 
Post-activity monitoring conducted by trained biological observers 
since about 1989 has not produced any sightings of distressed marine 
mammals.

Mitigation and Monitoring

    Based upon the analysis found in the Structure-Removal PEA (MMS, 
2005b), MMS believes that implementation of the mitigation measures 
listed in this section will prevent the occurrence of any mortality or 
serious injury to marine mammals.

Charge Criteria

    The charge criteria discussed here (e.g., charge size, detonation 
staggering, and explosive material) are applicable for all of the 
explosive-severance scenarios conducted under the proposed action.
Charge Size
    The options available under the multiple explosive-severance 
scenarios allow for the utilization of any size charge between 0 and 
500 lb (226.8 kg). Most often determined in the early planning stages, 
the final/actual charge weight establishes the specific monitoring 
scenario that must be adhered to as a condition of an MMPA 
authorization. Increasing the charge size results in increasing levels 
of mitigation/monitoring. Using explosives greater than 500 lb (226.8 
kg) are not proposed to be authorized for taking marine mammals under 
the MMPA. Use of explosives greater than 500 lb (226.8 kg) would 
require additional National Environmental Policy Act (NEPA) analyses, 
Endangered Species Act (ESA) consultations and an MMPA authorization 
prior to usage. As a result, no marine mammal takings are proposed to 
be authorized for charge weights greater than 500 lbs (226.8 kg) under 
this proposed rule.
Detonation Staggering
    Multiple-charge detonations are proposed to be staggered at an 
interval of 0.9 sec (900 msec) between blasts to prevent an additive 
pressure event. For decommissioning purposes, a ``multiple-charge 
detonation'' refers to any configuration where more than one charge is 
required in a single detonation ``event.''
Explosive Material
    There are many important properties (i.e., velocity, brisance, 
specific-energy, etc.) related to the explosive material(s) used in 
developing severance charges. Material needs vary widely depending upon 
target characteristics, marine conditions, and charge placement. Since 
specific material and personnel safety requirements must be established 
and followed, MMS believes that all decisions on explosive composition, 
configuration, and usage should be made by the qualified (i.e., 
licensed and permitted) explosive contractors in accordance with the 
applicable explosive-related laws and regulations. NMFS concurs, noting 
that limiting charge size or material may result in incomplete severing 
possibly requiring even larger charge weight to complete the severing.

Specific Mitigation/Monitoring Requirements

    Explosive severance activities, as described in the MMS application 
and PEA, have been grouped into five blasting categories (very small, 
small, standard, large, and specialty). Since the level of detonation 
pressure and energy is primarily related to the amount of the 
explosives used, these categories were developed cooperatively by MMS, 
NMFS and industry explosives experts based upon the specific range of 
charge weights needed to conduct current and future GOM OCS 
decommissionings. Depending on the design of the target and other 
variable marine conditions, the severance charges developed under each 
of these categories could be designed for use in either a below-mudline 
(BML) or above mudline (AML) configuration. These factors, combined 
with an activity location within either the shelf (less than 200 m (656 
ft)) or slope (greater than 200 m (656 ft)) species-delineation zone, 
result in 20 separate explosive-severance monitoring scenarios, as 
shown in Table 1.
BILLING CODE 3510-22-S

[[Page 17795]]



    The charge criteria previously listed are proposed to be standard 
for all decommissionings employing explosive-severance activities. 
However, depending upon the severance scenario, there are six different 
types of marine mammal/sea turtle monitoring surveys that must be 
conducted before and after all detonation events (sea turtles are 
included in these proposed mitigation and monitoring activities because 
NMFS and MMS anticipate that such measures will also minimize impacts 
to ESA-listed sea turtles). The specific monitoring requirements, 
survey times, and impact zone radii for all explosive-severance 
monitoring scenarios are summarized in Table 2.

[[Page 17796]]



BILLING CODE 3510-22-C
    Accounting for similar pre- and post-detonation surveys, the 20 
explosive-severance monitoring scenarios correspond roughly with 8 
basic mitigation processes that vary only in differences in impact zone 
ranges and survey times. As noted in Appendix E of MMS, 2005b, these 
impact zone radii were derived using the ``Under-Water Calculator,'' a 
verified model that predicts the detonation pressure/energy propagation 
resulting from underwater detonations. Time requisites were established 
by NMFS and MMS scientists, taking into consideration likely marine 
mammals/sea turtles and their surfacing/diving rates. Because of its 
complexity, the proposed mitigation/monitoring processes for each of 
the 20 explosive-severance scenarios is found in MMS, 2005a and is not 
repeated here. Instead, the proposed mitigation and monitoring 
summarized in Table 2 can be illustrated by using the Standard Blasting 
Category for shelf and slope waters as examples:

Shelf Waters (<200 m): Scenarios C1 and C3

    An operator proposing shelf-based, explosive-severance activities 
conducted under the standard blasting category will be limited to 80-lb 
charge sizes (BML or AML) and will be required to conduct all requisite 
monitoring during daylight hours out to

[[Page 17797]]

the associated impact-zone radii listed here:
    C1 -- 631 m (2,069 ft)
    C3 -- 829 m (2,721 ft)

Required Observers

    Generally, two observers who are trained and approved by an 
instructor with experience as an NMFS Platform Removal Observer Program 
(PROP) trainer (trained observer) are required to perform marine 
mammal/sea turtle detection surveys for standard-blasting under shelf 
water scenarios C1 and C3. If necessary, the site coordinator will 
determine if additional observers are required to compensate for the 
complexity of severance activities and/or structure configuration. In 
addition to meeting all reporting requirements, the trained observers 
will:
    1. Brief affected crew and severance contractors on the monitoring 
requirements and instruct topsides personnel to immediately report any 
sighted marine mammal/sea turtles to an observer or designated company 
representative;
    2. Establish an active line of communication (i.e., 2-way radio, 
visual signals, etc.) with company and blasting personnel; and
    3. Devote the entire, uninterrupted survey time to marine mammal/
sea turtle monitoring.
Pre-Detonation Monitoring
    Before severance-charge detonation, the trained observers will 
conduct a 90-min surface monitoring survey of the impact zone. The 
monitoring will be conducted from the highest vantage points and other 
locations which will provide comprehensive surveys of the surrounding 
area. Once the surface monitoring is complete (i.e., the impact zone 
determined to be clear of marine mammal/sea turtles), the trained 
observer(s) will transfer to a helicopter to conduct a 30-min (Scenario 
C1) or 45-min (Scenario C3) aerial monitoring survey. As per approved 
guidelines, the helicopter will transverse the impact zone at low 
speed/altitude in a specified grid pattern. If during the aerial survey 
a marine mammal/sea turtle is:
    1. Not sighted, proceed with the detonation;
    2. Sighted outbound and continuously tracked clearing the impact 
zone, proceed with the detonation after the monitoring time is complete 
to ensure no reentry;
    3. Sighted outbound and the marine mammal/sea turtle track is lost 
(e.g., the animal dives below the surface),
     Halt the detonation,
     Wait 30 min, and
     Reconduct the 30 min (C1) or 45 min (C3) aerial monitoring 
survey; or
    4. Sighted inbound,
     Halt the detonation,
     Wait 30 minutes, and
     Reconduct the 30-min (C1) or 45-min (C3) aerial monitoring 
survey.
    In the third and fourth scenarios, detonations will not proceed 
until they satisfy the first or second scenarios after the required 
aerial resurvey.
Post-Detonation Monitoring
    After severance charge detonation, the trained observer(s) will 
conduct a 30-min aerial monitoring survey of the impact zone to look 
for affected marine mammal/sea turtles. If a marine mammal/sea turtle 
is found shocked, seriously injured, or dead, the operations will cease 
and the observer will contact MMS and NMFS' Southeast Regional Office, 
attempts will be made, under the direction of the trained observer, to 
collect/resuscitate the animal, and the Southeast Region, NMFS will be 
contacted for additional instruction. If the animal does not revive, 
efforts should be made to recover it for necropsy in consultation with 
the appropriate NMFS' Stranding Coordinator. If no marine mammal/sea 
turtles are observed to be impacted by the detonation, the trained 
observer(s) will record all of the necessary information as required in 
MMS's permit approval letter and guidelines for the preparation of a 
trip report.
    A flowchart of the monitoring process and associated survey times 
for standard severance-scenarios C1 and C3 is provided in Figure 6 in 
MMS, 2005a.

Slope Waters (>200 m): Scenarios C2 and C4

    An operator proposing slope-based, explosive-severance activities 
conducted under the standard blasting category will be limited to 80-lb 
charge sizes (BML or AML) and conduct all requisite monitoring during 
daylight hours out to the associated impact-zone radii listed below:
    C2 -- 631 m (2,069 ft)
    C4 -- 829 m (2,721 ft)
Required Observers
    Slope water scenarios propose to require a minimum of three trained 
observers for the coordinated surface, aerial, and acoustic monitoring 
surveys, therefore, at least two ``teams'' of observers will be 
required. The PROP manager or his designee will determine each ``team'' 
size depending upon the complexity of severance activities and/or 
structure configuration. In addition to meeting all reporting 
requirements, the trained observers would perform the same functions as 
the observers in the shelf water scenarios C1 and C3.
Pre-Detonation Monitoring
    Before severance charge detonation, trained observers will begin a 
90-min surface monitoring survey and a 120-min (scenario C2) or 150-min 
(scenario C4) passive-acoustic monitoring survey of the impact zone. 
The surface monitoring will be conducted in the same manner as the C1 
and C3 scenarios. Once the surface monitoring is complete (i.e., the 
impact zone cleared of marine mammal/sea turtles), the acoustic survey 
will continue while the trained observer(s) transfer(s) to a helicopter 
to conduct a 30-min (scenario C2) or 60-min (scenario C4) aerial 
monitoring survey. As per approved guidelines, the helicopter will 
transverse the impact zone at low speed/altitude in a specified grid 
pattern.
    The proposed requirements on marine mammal and sea turtle sighting 
for the C1 and C3 scenarios would apply here except that the wait times 
and aerial survey times differ (see Table 2).
Post-Detonation Monitoring
    Scenarios C2 and C4 both would require the same post-detonation 
monitoring explained for the C1 and C3 scenarios.
    Scenario C4 also requires a post-post-detonation aerial monitoring 
survey to be conducted within 2-7 days after detonation activities 
conclude. Conducted by helicopter or fixed-wing aircraft, when 
applicable, observations are to start at the removal site and proceed 
leeward and outward of wind and current movement. If a marine mammal/
sea turtle is found shocked, injured, or dead, the operations will 
cease and the observer will contact MMS and NMFS' Southeast Regional 
Office, attempts will be made, under the direction of the trained 
observer, to collect/resuscitate the animal, and the Southeast Region, 
NMFS will be contacted for additional instruction. If the animal does 
not revive, efforts should be made to recover it for necropsy in 
consultation with the appropriate NMFS' Stranding Coordinator. Any 
injured or dead marine mammal/sea turtle must be recorded, and if 
possible, tracked after notifying NMFS. If no marine mammal/sea turtles 
are observed to be dead, injured, distressed, or shocked during either 
aerial survey, the trained observers will record all of the necessary 
information as detailed in MMS's permit approval letter and guidelines 
for the preparation of a trip report.
    A flowchart of the monitoring process and associated survey times 
for standard

[[Page 17798]]

explosive-severance monitoring scenarios C2 and C4 is provided in 
Figure 7 in MMS, 2005a.

Reporting Requirements

    All explosive-severance activities in the GOM would be mandated to 
abide by the reporting requirements listed in this section. The 
information collected will be used by MMS and NMFS to continually 
assess mitigation effectiveness and the level of marine mammal/sea 
turtle impacts.
    The reporting responsibilities will be undertaken by the NMFS' 
marine mammal/sea turtle observer for scenarios B1-E4 (Table 2) and the 
collected data will be prepared and routed in accordance with 
previously established guidelines for filing times and distribution.
    For very-small blasting scenarios A1-A4, the company observer will 
be responsible for recording the data and preparing a trip report for 
submittal within 30 days of completion of the severance activities. 
Trip reports for scenarios A1-A4 will be sent to MMS and NMFS Gulf/
Southeast regional offices.
    In addition to basic operational data (i.e., area and block, water 
depth, company/platform information, etc.), the observer reports must 
contain the following information: (1) Monitoring, (a) Survey Type, (i) 
pre-detonation), (ii) post-detonation, (iii) surface survey, (iv) 
aerial survey; (b) Time(s) (initiated/ terminated), (c) Marine 
Conditions (sea state etc.), (2) Observed Marine Protected Species 
(mammals/sea turtles), (a) Type/number (basic description or species 
identification (if possible)), (b) Location/orientation, (i) inside/
outside impact zone, (ii) inbound/outbound, etc., (c) Any ``halted-
detonation'' details (i.e., waiting periods, re-surveys, etc.), and (d) 
any ``Take-Event'' details - actual injury/mortality to marine 
protected species.
    In the event that a marine mammal or sea turtle is shocked, 
injured, or killed during the severance activities, the observer will 
report the incident to MMS and NMFS' Southeast Regional Office at the 
earliest opportunity.

Research

    To help determine the impact zones for the proposed blasting 
categories, MMS contracted for development of a model that would 
estimate shock wave and acoustic energy propagation caused by 
underwater explosive-severance tools (Dzwilewski and Fenton, 2003). As 
with most ``theoretical'' models developed to consider a wide range of 
parameters under multiple conditions, the contractor suggested that 
their modeling results be compared with in-situ data from actual 
explosive-severance activities. Previous in-situ research had been 
performed by the Naval Surface Warfare Center (NSWC) for MMS (Conner, 
1990), but uncertainties concerning transducer ranging devalued the 
sediment-attenuation conclusions. Considering the uncertainties, NMFS 
provided guidance suggesting that additional in-situ data comparison 
must be conducted.
    In November 2002, MMS's Technology Assessment and Research (TAR) 
Program began working with MMS's GOM Region to modify an existing 
project designed to develop and test the efficiency of linear shaped 
charges (Saint-Arnaud et al., 2004; see https://www.mms.gov/tarprojects/
429.htm). The modifications made it possible to allow BML, in situ data 
measurements to be taken during the final testing on actual OCS 
targets. While developing the measurement phase of the project, MMS 
again coordinated with NMFS to address the concerns expressed over the 
NSWC's range uncertainties, ultimately modifying field procedures to 
include the use of a sector-scanning sonar in conjunction with 
reflectors attached to each transducer array string. The testing was 
conducted, and Annex B of the project's final report (Appendix C of the 
Structure-Removal Operations PEA; USDOI, MMS, 2004) compares the peak 
overpressure (psi), impulse (psi-s), and energy flux density (EFD; psi-
in) measurements collected from the testing with calculated results 
from both the UWC and the applicable NSWC similitude equations.
    Since the number of targets, charge sizes, and marine conditions 
were limited, MMS is currently working with both industry and acoustic 
measurement groups to conduct additional research on targets offering a 
wider range of parameters. Similar to the TAR project, the research 
program under development will focus on in-situ ``targets-of-
opportunity'' offered by industry. As with previous work, the program 
will use transducer array assemblies to measure, record, and calculate 
the peak pressure, impulse, and acoustic energy released into the water 
column from severance charges. With a greater knowledge of the actual 
impacts, additional protective and mitigative measures may be possible 
in the future to address specific concerns of northern GOM marine 
mammals. In addition, the potential new information on impact-reducing 
factors (i.e., lower charge weights, increased BML cut depths, 
experimental mitigation techniques, etc.) will encourage industry to 
push research and development of less harmful and more efficient 
charges.
    As a result, NMFS is proposing to request continued research on the 
actual impacts of explosive severance activities, which includes, but 
is not limited to, additional in-situ acoustic measurement testing on 
decommissioning targets prior to any additional reauthorization for 
this activity under section 101(a)(5)(A) of the MMPA.

Preliminary Determinations

    NMFS has preliminarily determined that impacts to marine mammals 
from explosive-severance activities conducted under the proposed action 
will result in the taking (by Level B harassment) of small numbers of 
marine mammals, and have no more than a negligible impact on affected 
marine mammal stocks. Projected Level A harassment takes are very 
unlikely and would be limited to 3 species. No deaths or serious 
injuries to marine mammals or sea turtles are projected. If any marine 
mammals are displaced from preferred grounds, it will be for a short 
period of time (extending no greater than the structure removal 
activity itself). No critical habitat is involved in structure removal 
operations. Activities may disrupt behavioral patterns in a few 
individuals of a few species, but no effect is projected on annual 
recruitment or survival. With proposed mitigation measures in place, 
the potential impacts on marine mammals are expected to be negligible 
and at the lowest level practicable.

ESA

    Under section 7 of the ESA, MMS has begun consultation on the 
proposed explosive severance activtiy. NMFS will also consult on the 
issuance of regulations and LOAs under section 101(a)(5)(A) of the MMPA 
for this activity. Consultation will be concluded prior to a 
determination on the issuance of regulations.

NEPA

    MMS completed and released its PEA to the public for review on 
February 28, 2005. That document is available (see ADDRESSES) to the 
public. NMFS is reviewing the PEA and will either adopt it or prepare 
its own NEPA document before making a determination on the issuance of 
regulations and LOAs for this activity.

Information Solicited

    NMFS requests interested persons to submit comments, information, 
and suggestions concerning MMS'

[[Page 17799]]

application and this proposed rule. NMFS requests commenters also read 
the MMS application and PEA on this action prior to submitting 
comments.

Classification

    This action has been determined to be not significant for purposes 
of Executive Order 12866.
    The Chief Counsel for Regulation of the Department of Commerce has 
certified to the Chief Counsel for Advocacy of the Small Business 
Administration that this proposed rule, if adopted, would not have a 
significant economic impact on a substantial number of small entities. 
If implemented, this rule would authorize takings of marine mammals, 
otherwise prohibited by the MMPA, incidental to the explosive removal 
of offshore oil and gas structures in the GOM. Most offshore structures 
are owned by large- and medium-sized oil and gas companies and by 
definition, are not small businesses. However, this rule may affect a 
number of contractors providing services related to the demolition of 
these structures and monitoring marine mammal takes. Some of the 
affected contractors may be small businesses, but the number involved 
are very small. Further, since the authorization to incidentally take 
marine mammals by this activity facilitates structure removal, 
implementation of this rulemaking action would lead to the need for 
their services. As a result, the economic impact on them would be 
beneficial. Because of this certification, a regulatory flexibility 
analysis is not required and none has been prepared.
    Notwithstanding any other provision of law, no person is required 
to respond to nor shall a person be subject to a penalty for failure to 
comply with a collection of information subject to the requirements of 
the Paperwork Reduction Act (PRA) unless that collection of information 
displays a currently valid OMB control number. This proposed rule 
contains collection-of-information requirements subject to the 
provisions of the PRA. These requirements have been approved by OMB 
under control number 0648-0151, and include applications for LOAs, and 
reports.
    The reporting burden for the approved collections-of-information is 
estimated to be approximately 3 hours for each company applying for an 
annual LOA. As in previous years, NMFS expects that approximately 20-30 
companies to apply for LOAs annually. These estimates include the time 
for reviewing instructions, searching existing data sources, gathering 
and maintaining the data needed, and completing and reviewing the 
collection-of-information. Send comments regarding these burden 
estimates, or any other aspect of this data collection, including 
suggestions for reducing the burden, to NMFS and OMB (see ADDRESSES).

List of Subjects in 50 CFR Part 216

    Exports, Fish, Imports, Indians, Labeling, Marine mammals, 
Penalties, Reporting and recordkeeping requirements, Seafood, 
Transportation.

    Dated: March 31, 2006.
James W. Balsiger,
Deputy Assistant Administrator for Regulatory Programs, National Marine 
Fisheries Service.
    For reasons set forth in the preamble, 50 CFR part 216 is proposed 
to be amended as follows:

PART 216--REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE 
MAMMALS

    1. The authority citation for part 216 continues to read as 
follows:

    Authority: 16 U.S.C. 1361 et seq.
    2. Subpart R is added and reserved.
    3. Subpart S is added consisting of Sec. Sec.  216.210 through 
216.218 to read as follows:

Subpart S--Taking of Marine Mammals Incidental to Explosive 
Severance Activities Conducted During Structure Removal Operations 
on the Outer Continental Shelf in the U.S. Gulf of Mexico

Sec.
216.210 Specified activity and specified geographical region.
216.211 Effective dates.
216.212 Permissible methods of taking.
216.213 Prohibitions.
216.214 Definitions, terms, and criteria.
216.215 Mitigation.
216.216 Requirements for monitoring and reporting.
216.217 Letters of Authorization.
216.218 Renewal of, and modifications to, Letters of Authorization.

Subpart S--Taking of Marine Mammals Incidental to Explosive 
Severance Activities Conducted During Structure Removal Operations 
on the Outer Continental Shelf in the U.S. Gulf of Mexico


Sec.  216.210  Specified activity and specified geographical region.

    (a) Regulations in this subpart apply only to the incidental taking 
of those marine mammal species specified in paragraph (b) of this 
section by U.S. citizens engaged in explosive severance activities 
conducted during offshore oil and gas structure removal activities in 
areas within state and/or Federal waters in the U.S. Gulf of Mexico 
adjacent to the coasts of Texas, Mississippi, Louisiana, Alabama, and 
Florida. The incidental, but not intentional, taking of marine mammals 
by U.S. citizens holding a Letter of Authorization issued under 
Sec. Sec.  216.106 and 216.217 is permitted during the course of 
severing pilings, well conductors, and related supporting structures, 
and other activities related to the removal of the oil and gas 
structure.
    (b) The incidental take of marine mammals under the activity 
identified in paragraph (a) of this section is limited annually to a 
total of 1 bottlenose dolphin by Level A harassment and 457 marine 
mammals by Level B harassment, limited to the following species: sperm 
whale, pygmy sperm whale, dwarf sperm whale, Cuvier's beaked whale, 
Sowerby's beaked whale, Gervais' beaked whale, Blainville's beaked 
whale, rough-toothed dolphin, bottlenose dolphin, pantropical spotted 
dolphin, Atlantic spotted dolphin, spinner dolphin, Clymene dolphin, 
striped dolphin, Fraser's dolphin, Risso's dolphin, melon-headed whale, 
pygmy killer whale, false killer whale, killer whale, short-finned 
pilot whale, North Atlantic right whale, humpback whale, minke whale, 
Bryde's whale, sei whale, fin whale, and blue whale.


Sec.  216.211  Effective dates.

    Regulations in this subpart are effective from July 15, 2006 
through July 14, 2011.


Sec.  216.212  Permissible methods of taking.

    The Holder of a Letter of Authorization issued pursuant to 
Sec. Sec.  216.106 and 216.217, may incidentally, but not 
intentionally, take marine mammals by harassment within the area 
described in Sec.  216.210(a), provided the activity is in compliance 
with all terms, conditions, and requirements of these regulations and 
the appropriate Letter of Authorization.


Sec.  216.213  Prohibitions.

    Notwithstanding takings authorized by a Letter of Authorization 
issued under Sec. Sec.  216.106 and 216.217, no person in connection 
with the activities described in Sec.  216.210(a) shall:
    (a) Take any marine mammal not specified in Sec.  216.210(b);
    (b) Take any marine mammal specified in Sec.  216.210(b) in a 
manner or amount greater than described therein;
    (c) Take a marine mammal specified in Sec.  216.210(b) if such 
taking results in more than a negligible impact on the

[[Page 17800]]

species or stocks of such marine mammal;
    (d) Violate, or fail to comply with, the terms, conditions, and 
requirements of these regulations or a Letter of Authorization issued 
under Sec.  216.217;
    (e) Take a marine mammal in violation of these regulations by using 
a charge with a weight greater than 500 lbs (227 kg);
    (f) Take a marine mammal when conditions preclude conducting 
mitigation and monitoring requirements of these regulations or a Letter 
of Authorization.


Sec.  216.214  Definitions, terms, and criteria.

    (a) Definitions. (1) Below-mud-line or BML means that the 
explosives are detonated below the water-mud interface, either inside 
or outside a pipe, other structure or cable.
    (2) Above-mud-line or AML means that the explosives are detonated 
in the water column either inside or outside a pipe, other structure or 
cable.
    (3) Multiple charge detonation means any explosive configuration 
where more than one charge is required in a single detonation event.
    (4) Scenario means an alpha-numeric designation provided to 
describe charge size, activity location, and target design employed in 
order to apply appropriate marine mammal monitoring measures.
    (b) Terms. (1) Impact zone (required for all scenarios). The impact 
zone means the area (i.e., a horizontal radius around a decommissioning 
target) in which a marine mammal could be affected by the pressure and 
or acoustic energy released during the detonation of an explosive-
severance charge.
    (2) Predetonation survey (required for all scenarios). A 
predetonation (pre-det) survey means any marine mammal monitoring 
survey (e.g., surface, aerial, or acoustic) conducted prior to the 
detonation of any explosive severance tool.
    (3) Postdetonation survey (required for all scenarios). A 
postdetonation (post-det) survey means any marine mammal monitoring 
survey (e.g., surface, aerial, or post-post-det aerial) conducted after 
the detonation event occurs.
    (4) Waiting period (required for all scenarios). Variable by 
scenario, the waiting period refers to the time in which detonation 
operations must hold before the requisite monitoring survey(s) can be 
reconducted.
    (5) Company observer (for scenarios A1-A4 only). Trained company 
observers are authorized to perform marine mammal detection surveys for 
``very-small'' blasting scenarios A1-A4.
    (6) Trained observer (for scenarios B1-E4). Trained observers are 
observers trained and approved by an instructor with experience as a 
NMFS Platform Removal Observer Program trainer. Trained observers are 
required to perform marine mammal detection surveys for all detonation 
scenarios with the exception of scenarios A1-A4. Two observers will be 
assigned to each operation for detection survey duties. However, 
because mitigation-scenarios C2, C4, D2, D4, E2, and E4 require a 
minimum of three observers for the simultaneous surface, aerial, and 
acoustic surveys, at least two ``teams'' of observers will be required.
    (c) Blasting category parameters and associated severance 
scenarios. To determine the appropriate marine mammal mitigation and 
monitoring requirements in Sec. Sec.  216.217 and 216.218, holders of 
Letters of Authorization under this subpart must determine, from this 
table, the appropriate explosive severance scenario to follow for the 
blasting category, biological zone, and charge configuration for their 
activity.

BILLING CODE 3510-22-S

[[Page 17801]]



BILLING CODE 3510-22-C


Sec.  216.215  Mitigation.

    The activity identified in Sec.  216.210(a) must be conducted in a 
manner that minimizes, to the greatest extent practicable, adverse 
impacts on marine mammals and their habitats. When conducting 
operations identified in Sec.  216.210(a), all mitigation measures 
contained in the Letter of Authorization issued under Sec. Sec.  
216.106 and 216.217 must be implemented. Any mitigation measures 
proposed to be contained in a Letter of Authorization that are not 
specified in this subpart, or not considered an emergency requirement 
under Sec.  216.218(d), will first be subject to public notice and 
comment through publication in the Federal Register, as provided by 
Sec.  216.218(c). When using explosives, the following mitigation 
measures must be carried out:
    (a)(1) If marine mammals are observed within (or about to enter) 
the relevant marine mammal impact zone identified in Sec.  216.214 (c) 
column 4 for the relevant charge range and configuration (i.e., BML or 
AML) for the activity, detonation must be delayed until the marine 
mammal(s) are outside that zone;
    (2) Required pre-detonation surveys must begin no earlier than 1 
hour after sunrise and detonations must not occur if the post-
detonation survey cannot be concluded prior to 1 hour before sunset;
    (3) Whenever weather and/or sea conditions preclude adequate 
aerial, shipboard or subsurface marine mammal monitoring as determined 
by the trained observer, detonations must be delayed until conditions 
improve sufficiently for marine mammal monitoring to be undertaken or 
resumed;
    (4) Whenever the weather and sea conditions prevent implementation 
of the aerial survey monitoring required under
    Sec.  216.216(c)(2), the aerial survey must be repeated prior to 
detonation of charges; and
    (5) Multiple charge detonations must be staggered at an interval of 
0.9 sec (900 msec) between blasts.
    (b) If a marine mammal/sea turtle is found shocked, injured, or 
dead, the explosive severance activity will immediately cease and the 
holder of the Letter of Authorization, designee or the lead observer 
will contact the Minerals Management Service and the Regional 
Administrator, National Marine Fisheries Service' Southeast Regional 
Office, or designee at the earliest opportunity.


Sec.  216.216  Requirements for monitoring and reporting.

    (a) Holders of Letters of Authorization issued for activities 
described in Sec.  216.210(a) are required to cooperate with the 
National Marine Fisheries Service, and any other Federal, state or 
local agency monitoring the impacts of the activity on marine mammals.
    (b) Holders of Letters of Authorization must fully comply with the 
relevant mitigation and monitoring program for the explosive-severance 
activity that corresponds to the blast scenario in Sec.  216.216(e)).
    (c) Holders of Letters of Authorization must ensure that the 
following

[[Page 17802]]

monitoring programs are conducted as appropriate for the required 
monitoring scenario