(a) When conducting the activities identified in § 218.150(c), the mitigation measures contained in any LOA issued under §§ 216.106 of this chapter and 218.156 must be implemented. If Navy contractors are serving in a role similar to Navy personnel, Navy contractors will follow the mitigation applicable to Navy personnel. These mitigation measures include, but are not limited to:

(1) Procedural mitigation. Procedural mitigation is mitigation that the Navy must implement whenever and wherever an applicable training activity takes place within the GOA Study Area for acoustic stressors (i.e., active sonar, weapons firing noise), explosive stressors (i.e., large-caliber projectiles, bombs), and physical disturbance and strike stressors (i.e., vessel movement, towed in-water devices, small-, medium-, and large-caliber non-explosive practice munitions, non-explosive bombs).

(i) Environmental awareness and education. Appropriate Navy personnel (including civilian personnel) involved in mitigation and training activity reporting under the specified activities must complete the environmental compliance training modules identified in their career path training plan, as specified in the LOA.

(ii) Active sonar. Active sonar includes mid-frequency active sonar and high-frequency active sonar. For vessel-based active sonar activities, mitigation applies only to sources that are positively controlled and deployed from manned surface vessels (e.g., sonar sources towed from manned surface platforms). For aircraft-based active sonar activities, mitigation applies only to sources that are positively controlled and deployed from manned aircraft that do not operate at high altitudes (e.g., rotary-wing aircraft). Mitigation does not apply to active sonar sources deployed from unmanned aircraft or aircraft operating at high altitudes (e.g., maritime patrol aircraft).

(A) Number of Lookouts and observation platform for hull-mounted sources. For hull-mounted sources, the Navy must have one Lookout for platforms with space or manning restrictions while underway (at the forward part of a small boat or ship) and platforms using active sonar while moored or at anchor; and two Lookouts for platforms without space or manning restrictions while underway (at the forward part of the ship).

(B) Number of Lookouts and observation platform for sources not hull-mounted. For sources that are not hull-mounted, the Navy must have one Lookout on the ship or aircraft conducting the activity.

(C) Prior to activity. Prior to the initial start of the activity (e.g., when maneuvering on station), Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammal is observed, Navy personnel must relocate or delay the start of active sonar transmission until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (a)(1)(ii)(F) of this section are met for marine mammals.

(D) During the activity for hull-mounted mid-frequency active sonar. During the activity, for hull-mounted mid-frequency active sonar, Navy personnel must observe the following mitigation zones for marine mammals.

(1) Powerdowns for marine mammals. Navy personnel must power down active sonar transmission by 6 dB if a marine mammal is observed within 1,000 yd (914.4 m) of the sonar source; Navy personnel must power down active sonar transmission an additional 4 dB (10 dB total) if a marine mammal is observed within 500 yd (457.2 m) of the sonar source.

(2) Shutdowns for marine mammals. Navy personnel must cease transmission if a marine mammal is observed within 200 yd (182.9 m) of the sonar source.

(E) During the activity, for mid-frequency active sonar sources that are not hull-mounted, and high-frequency active sonar. During the activity, for mid-frequency active sonar (MFAS) sources that are not hull-mounted and high-frequency active sonar (HFAS), Navy personnel must observe the mitigation zone for marine mammals. Navy personnel must cease transmission if a marine mammal is observed within 200 yd (182.9 m) of the sonar source.

(F) Commencement/recommencement conditions after a marine mammal sighting before or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing or powering up active sonar transmission) until one of the following conditions has been met:

(1) Observed exiting. The animal is observed exiting the mitigation zone;

(2) Thought to have exited. The animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the sonar source;

(3) Clear from additional sightings. The mitigation zone has been clear from any additional sightings for 10 minutes (min) for aircraft-deployed sonar sources or 30 minutes for vessel-deployed sonar sources;

(4) Sonar source transit. For mobile activities, the active sonar source has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting; or

(5) Bow-riding dolphins. For activities using hull-mounted sonar, the Lookout concludes that dolphins are deliberately closing in on the ship to ride the ship's bow wave, and are therefore out of the main transmission axis of the sonar (and there are no other marine mammal sightings within the mitigation zone).

(iii) Weapons firing noise. Weapons firing noise associated with large-caliber gunnery activities.

(A) Number of Lookouts and observation platform. One Lookout must be positioned on the ship conducting the firing. Depending on the activity, the Lookout could be the same as the one provided for in paragraphs (a)(1)(iv)(A) and (a)(1)(viii)(A) of this section.

(B) Mitigation zone. Thirty degrees on either side of the firing line out to 70 yd (64 m) from the muzzle of the weapon being fired.

(C) Prior to activity. Prior to the initial start of the activity, Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammal is observed, Navy personnel must relocate or delay the start of weapons firing until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (a)(1)(iii)(E) of this section are met for marine mammals.

(D) During activity. During the activity, Navy personnel must observe the mitigation zone for marine mammals; if a marine mammal is observed, Navy personnel must cease weapons firing.

(E) Commencement/recommencement conditions after a marine mammal sighting before or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing weapons firing) until one of the following conditions has been met:

(1) Observed exiting. The animal is observed exiting the mitigation zone;

(2) Thought to have exited. The animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the firing ship;

(3) Clear from additional sightings. The mitigation zone has been clear from any additional sightings for 30 min; or

(4) Firing ship transit. For mobile activities, the firing ship has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting.

(iv) Explosive large-caliber projectiles. Gunnery activities using explosive large-caliber projectiles. Mitigation applies to activities using a surface target.

(A) Number of Lookouts and observation platform. One Lookout must be on the vessel or aircraft conducting the activity. Depending on the activity, the Lookout could be the same as the one described in paragraph (a)(1)(iii)(A) of this section. If additional platforms are participating in the activity, Navy personnel positioned in those assets (e.g., safety observers, evaluators) must support observing the mitigation zone for marine mammals while performing their regular duties.

(B) Mitigation zones. 1,000 yd (914.4 m) around the intended impact location.

(C) Prior to activity. Prior to the initial start of the activity (e.g., when maneuvering on station), Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammal is observed, Navy personnel must relocate or delay the start of firing until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (a)(1)(iv)(E) of this section are met for marine mammals.

(D) During activity. During the activity, Navy personnel must observe the mitigation zone for marine mammals; if a marine mammal is observed, Navy personnel must cease firing.

(E) Commencement/recommencement conditions after a marine mammal sighting before or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing firing) until one of the following conditions has been met:

(1) Observed exiting. The animal is observed exiting the mitigation zone;

(2) Thought to have exited. The animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended impact location;

(3) Clear of additional sightings. The mitigation zone has been clear from any additional sightings for 30 minutes; or,

(4) Impact location transit. For activities using mobile targets, the intended impact location has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting.

(F) After activity. After completion of the activity (e.g., prior to maneuvering off station), Navy personnel must, when practical (e.g., when platforms are not constrained by fuel restrictions or mission-essential follow-on commitments), observe for marine mammals in the vicinity of where detonations occurred; if any injured or dead marine mammals are observed, Navy personnel must follow established incident reporting procedures. If additional platforms are supporting this activity (e.g., providing range clearance), Navy personnel positioned on these Navy assets must assist in the visual observation of the area where detonations occurred.

(v) Explosive bombs—(A) Number of Lookouts and observation platform. One Lookout must be positioned in an aircraft conducting the activity. If additional platforms are participating in the activity, Navy personnel positioned in those assets (e.g., safety observers, evaluators) must support observing the mitigation zone for marine mammals while performing their regular duties.

(B) Mitigation zone. 2,500 yd (2,286 m) around the intended target.

(C) Prior to activity. Prior to the initial start of the activity (e.g., when arriving on station), Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammal is observed, Navy personnel must relocate or delay the start of bomb deployment until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (a)(1)(v)(E) of this section are met for marine mammals.

(D) During activity. During the activity (e.g., during target approach), Navy personnel must observe the mitigation zone for marine mammals; if a marine mammal is observed, Navy personnel must cease bomb deployment.

(E) Commencement/recommencement conditions after a marine mammal sighting before or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing bomb deployment) until one of the following conditions has been met:

(1) Observed exiting. The animal is observed exiting the mitigation zone;

(2) Thought to have exited. The animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended target;

(3) Clear from additional sightings. The mitigation zone has been clear from any additional sightings for 10 min; or

(4) Intended target transit. For activities using mobile targets, the intended target has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting.

(F) After activity. After completion of the activity (e.g., prior to maneuvering off station), Navy personnel must, when practical (e.g., when platforms are not constrained by fuel restrictions or mission-essential follow-on commitments), observe for marine mammals in the vicinity of where detonations occurred; if any injured or dead marine mammals are observed, Navy personnel must follow established incident reporting procedures. If additional platforms are supporting this activity (e.g., providing range clearance), Navy personnel positioned on these Navy assets must assist in the visual observation of the area where detonations occurred.

(vi) Vessel movement. The mitigation will not be applied if: the vessel's safety is threatened; the vessel is restricted in its ability to maneuver (e.g., during launching and recovery of aircraft or landing craft, during towing activities, when mooring); the vessel is submerged or operated autonomously; or when impractical based on mission requirements (e.g., during Vessel Visit, Board, Search, and Seizure activities as military personnel from ships or aircraft board suspect vessels).

(A) Number of Lookouts and observation platform. One or more Lookouts must be on the underway vessel. If additional watch personnel are positioned on the underway vessel, those personnel (e.g., persons assisting with navigation or safety) must support observing for marine mammals while performing their regular duties.

(B) Mitigation zone—(1) Whales. 500 yd (457.2 m) around the vessel for whales.

(2) Marine mammals other than whales. 200 yd (182.9 m) around the vessel for all marine mammals other than whales (except those intentionally swimming alongside or closing in to swim alongside vessels, such as bow-riding or wake-riding dolphins).

(C) When underway. Navy personnel must observe the direct path of the vessel and waters surrounding the vessel for marine mammals. If a marine mammal is observed in the direct path of the vessel, Navy personnel must maneuver the vessel as necessary to maintain the appropriate mitigation zone distance. If a marine mammal is observed within waters surrounding the vessel, Navy personnel must maintain situational awareness of that animal's position. Based on the animal's course and speed relative to the vessel's path, Navy personnel must maneuver the vessel as necessary to ensure that the appropriate mitigation zone distance from the animal continues to be maintained.

(D) Incident reporting procedures. If a marine mammal vessel strike occurs, Navy personnel must follow the established incident reporting procedures.

(vii) Towed in-water devices. Mitigation applies to devices that are towed from a manned surface platform or manned aircraft, or when a manned support craft is already participating in an activity involving in-water devices being towed by unmanned platforms. The mitigation will not be applied if the safety of the towing platform or in-water device is threatened.

(A) Number of Lookouts and observation platform. One Lookout must be positioned on a manned towing platform or support craft.

(B) Mitigation zone. 250 yd (228.6 m) around the towed in-water device for marine mammals (except those intentionally swimming alongside or choosing to swim alongside towing vessels, such as bow-riding or wake-riding dolphins).

(C) During activity. During the activity (i.e., when towing an in-water device), Navy personnel must observe the mitigation zone for marine mammals; if a marine mammal is observed, Navy personnel must maneuver to maintain distance.

(viii) Small-, medium-, and large-caliber non-explosive practice munitions. Gunnery activities using small-, medium-, and large-caliber non-explosive practice munitions. Mitigation applies to activities using a surface target.

(A) Number of Lookouts and observation platform. One Lookout must be positioned on the platform conducting the activity. Depending on the activity, the Lookout could be the same as the one described in paragraph (a)(1)(iii)(A) of this section.

(B) Mitigation zone. 200 yd (182.9 m) around the intended impact location.

(C) Prior to activity. Prior to the initial start of the activity (e.g., when maneuvering on station), Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammal is observed, Navy personnel must relocate or delay the start of firing until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (a)(1)(viii)(E) of this section are met for marine mammals.

(D) During activity. During the activity, Navy personnel must observe the mitigation zone for marine mammals; if a marine mammal is observed, Navy personnel must cease firing.

(E) Commencement/recommencement conditions after a marine mammal sighting before or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing firing) until one of the following conditions has been met:

(1) Observed exiting. The animal is observed exiting the mitigation zone;

(2) Thought to have exited. The animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended impact location;

(3) Clear of additional sightings. The mitigation zone has been clear from any additional sightings for 10 minutes for aircraft-based firing or 30 minutes for vessel-based firing; or

(4) Impact location transit. For activities using a mobile target, the intended impact location has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting.

(ix) Non-explosive bombs—(A) Number of Lookouts and observation platform. One Lookout must be positioned in an aircraft.

(B) Mitigation zone. 1,000 yd (914.4 m) around the intended target.

(C) Prior to activity. Prior to the initial start of the activity (e.g., when arriving on station), Navy personnel must observe the mitigation zone for floating vegetation and marine mammals; if floating vegetation or a marine mammal is observed, Navy personnel must relocate or delay the start of bomb deployment until the mitigation zone is clear of floating vegetation or until the conditions in paragraph (a)(1)(ix)(E) of this section are met for marine mammals.

(D) During activity. During the activity (e.g., during approach of the target), Navy personnel must observe the mitigation zone for marine mammals and, if a marine mammal is observed, Navy personnel must cease bomb deployment.

(E) Commencement/recommencement conditions after a marine mammal sighting prior to or during the activity. Navy personnel must allow a sighted marine mammal to leave the mitigation zone prior to the initial start of the activity (by delaying the start) or during the activity (by not recommencing bomb deployment) until one of the following conditions has been met:

(1) Observed exiting. The animal is observed exiting the mitigation zone;

(2) Thought to have exited. The animal is thought to have exited the mitigation zone based on a determination of its course, speed, and movement relative to the intended target;

(3) Clear from additional sightings. The mitigation zone has been clear from any additional sightings for 10 min; or

(4) Intended target transit. For activities using mobile targets, the intended target has transited a distance equal to double that of the mitigation zone size beyond the location of the last sighting.

(2) Mitigation areas. In addition to procedural mitigation, Navy personnel must implement mitigation measures within mitigation areas to avoid or reduce potential impacts on marine mammals.

(i) North Pacific Right Whale Mitigation Area. Figure 1 to this paragraph (a)(2) shows the location of the mitigation area.

(A) Surface ship hull-mounted MF1 mid-frequency active sonar. From June 1-September 30 within the North Pacific Right Whale Mitigation Area, Navy personnel must not use surface ship hull-mounted MF1 mid-frequency active sonar during training.

(B) National security exception. Should national security require that the Navy cannot comply with the restrictions in paragraph (a)(2)(i)(A) of this section, Navy personnel must obtain permission from the designated Command, U.S. Third Fleet Command Authority, prior to commencement of the activity. Navy personnel must provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS.

(ii) Continental Shelf and Slope Mitigation Area. Figure 1 to this paragraph (a)(2) shows the location of the mitigation area.

(A) Explosives. During training, Navy personnel must not detonate explosives below 10,000 ft. altitude (including at the water surface) in the Continental Shelf and Slope Mitigation Area, which extends over the continental shelf and slope out to the 4,000 m depth contour within the TMAA.

(B) National security exception. Should national security require that the Navy cannot comply with the restrictions in paragraph (a)(2)(ii)(A) of this section, Navy personnel must obtain permission from the designated Command, U.S. Third Fleet Command Authority, prior to commencement of the activity. Navy personnel must provide NMFS with advance notification and include information about the event in its annual activity reports to NMFS.

(iii) Pre-event awareness notifications in the Temporary Maritime Activities Area. The Navy must issue pre-event awareness messages to alert vessels and aircraft participating in training activities within the TMAA to the possible presence of concentrations of large whales on the continental shelf and slope. Occurrences of large whales may be higher over the continental shelf and slope relative to other areas of the TMAA. Large whale species in the TMAA include, but are not limited to, fin whale, blue whale, humpback whale, gray whale, North Pacific right whale, sei whale, and sperm whale. To maintain safety of navigation and to avoid interactions with marine mammals, the Navy must instruct personnel to remain vigilant to the presence of large whales that may be vulnerable to vessel strikes or potential impacts from training activities. Additionally, Navy personnel must use the information from the awareness notification messages to assist their visual observation of applicable mitigation zones during training activities and to aid in the implementation of procedural mitigation.

Figure 1 to Paragraph (a)(2)—Geographic Mitigation Areas for Marine Mammals in the GOA Study Area

(b) [Reserved]