§ 217.134 - Mitigation requirements.

§ 217.134 Mitigation requirements.

When conducting the activities identified in § 217.130(a), the mitigation measures contained in any LOA issued under § 216.106 and § 217.136 of this chapter must be implemented. These mitigation measures include but are not limited to:

(a) General conditions:

(1) If any marine mammal species not listed in § 217.132(b) are observed during conduct of the activities identified in § 217.130(a) and are likely to be exposed to sound pressure levels (SPLs) greater than or equal to 160 dB re 1 µPa (rms), Apache must avoid such exposure (e.g., by altering speed or course or by power down or shutdown of the sound source).

(2) If the allowable number of takes on an annual basis listed for any marine mammal species in § 217.132(b) is exceeded, or if any marine mammal species not listed in § 217.132(b) is exposed to SPLs greater than or equal to 160 dB re 1 µPa (rms), Apache shall immediately cease survey operations involving the use of active sound sources (e.g., airguns and pingers), record the observation, and notify NMFS Office of Protected Resources.

(3) Apache must notify the Office of Protected Resources, NMFS, at least 48 hours prior to the start of seismic survey activities each year.

(4) Apache shall conduct briefings as necessary between vessel crews, marine mammal monitoring team, and other relevant personnel prior to the start of all survey activity, and when new personnel join the work, in order to explain responsibilities, communication procedures, marine mammal monitoring protocol, operational procedures, and reporting requirements.

(b) Visual monitoring.

(1) Apache shall establish zones corresponding to the area around the source within which SPLs are expected to equal or exceed relevant acoustic criteria for Level A and Level B harassment. These zones shall be established as exclusion zones (shutdown zones, described in in § 217.134 (c)(2)) to avoid Level A harassment of any marine mammal, Level B harassment of beluga whales, or Level B harassment of aggregations of five or more killer whales or harbor porpoises. For all marine mammals other than beluga whales or aggregations of five or more harbor porpoises or killer whales, the Level B harassment zone shall be established as a disturbance zone and monitored as described in § 217.135(a)(1). These zones shall be defined in each annual LOA to allow for incorporation of new field measurements.

(2) Vessel-based monitoring for marine mammals must be conducted before, during, and after all activity identified in § 217.130(a) that is conducted during daylight hours (defined as nautical twilight-dawn to nautical twilight-dusk), and shall begin at least thirty minutes prior to the beginning of survey activity, continue throughout all survey activity that occurs during daylight hours, and conclude no less than thirty minutes following the cessation of survey activity. Apache shall use a sufficient number of qualified protected species observers (PSO), at least two PSOs per vessel, to ensure continuous visual observation coverage during all periods of daylight survey operations with maximum limits of four consecutive hours on watch and twelve hours of watch time per day per PSO. One PSO must be a supervisory field crew leader. A minimum of two qualified PSOs shall be on watch at all times during daylight hours on each source and support vessel (except during brief meal and restroom breaks, when at least one PSO shall be on watch).

(i) A qualified PSO is a third-party trained biologist, with prior experience as a PSO during seismic surveys and the following minimum qualifications:

(A) Visual acuity in both eyes (correction is permissible) sufficient for discernment of moving targets at the water's surface with ability to estimate target size and distance; use of binoculars may be necessary to correctly identify the target;

(B) Advanced education in biological science or related field (undergraduate degree or higher required);

(C) Experience and ability to conduct field observations and collect data according to assigned protocols (this may include academic experience);

(D) Experience or training in the field identification of marine mammals, including the identification of behaviors;

(E) Sufficient training, orientation, or experience with the survey operation to provide for personal safety during observations;

(F) Writing skills sufficient to prepare a report of observations including but not limited to the number and species of marine mammals observed; dates and times when survey activities were conducted; dates and times when survey activities were suspended to avoid exposure of marine mammals to sound within defined exclusion zones; and marine mammal behavior; and

(G) Ability to communicate orally, by radio or in person, with project personnel to provide real-time information on marine mammals observed in the area as necessary.

(ii) PSOs must have access to binoculars (7 x 50 with reticle rangefinder; Fujinon or equivalent quality), and optical rangefinders, and shall scan the surrounding waters from the best available suitable vantage point with the naked eye and binoculars. At least one PSO shall scan the surrounding waters during all daylight hours using bigeye binoculars.

(iii) PSOs shall also conduct visual monitoring:

(A) While the airgun array and nodes are being deployed or recovered from the water; and

(B) During periods of good visibility when the sound sources are not operating for comparison of animal abundance and behavior.

(iv) PSOs shall be on watch at all times during daylight hours when survey operations are being conducted, unless conditions (e.g., fog, rain, darkness) make observations impossible. The lead PSO on duty shall make this determination. If conditions deteriorate during daylight hours such that the sea surface observations are halted, visual observations must resume as soon as conditions permit.

(3) Survey activity must begin during periods of good visibility, which is defined as daylight hours when weather (e.g., fog, rain) does not obscure the relevant exclusion zones within maximum line-of-sight. In order to begin survey activity, the relevant taxa-specific exclusion zones must be clear of marine mammals for not less than thirty minutes. If marine mammals are present within or are observed approaching the relevant exclusion zone during this thirty-minute pre-clearance period, the start of survey activity shall be delayed until the animals are observed leaving the zone of their own volition and/or outside the zone or until fifteen minutes (for pinnipeds and harbor porpoises) or thirty minutes (for beluga whales, killer whales, and gray whales) have elapsed without observing the animal. While activities will be permitted to continue during low-visibility conditions, they must have been initiated following proper clearance of the exclusion zone under acceptable observation conditions and must be restarted, if shut down for greater than ten minutes for any reason, using the appropriate exclusion zone clearance procedures.

(c) Ramp-up and shutdown.

(1) Survey activity involving the full-power airgun array or shallow-water source must be initiated, following appropriate clearance of the exclusion zone, using accepted ramp-up procedures. Ramp-up is required at the start of survey activity and at any time following a shutdown of ten minutes or greater. Ramp-up shall be implemented by starting the smallest single gun available and increasing the operational array volume in a defined sequence such that the source level of the array shall increase in steps not exceeding approximately 6 dB per five-minute period. PSOs shall continue monitoring the relevant exclusion zones throughout the ramp-up process and, if marine mammals are observed within or approaching the zones, a power down or shutdown shall be implemented and ramp-up restarted following appropriate exclusion zone clearance procedures as described in paragraph (b)(3) of this section.

(2) Apache must shut down or power down the source, as appropriate, immediately upon detection of any marine mammal approaching or within the relevant Level A exclusion zone or upon detection of any beluga whale or aggregation of five or more harbor porpoises or killer whales approaching or within the relevant Level B exclusion zone. Power down is defined as reduction of total airgun array volume from either the full-power airgun array (2,400 in³) or the shallow-water source (440 in³) to a single mitigation gun (maximum 10 in³). Power down must be followed by shutdown in the event that the animal(s) approach the exclusion zones defined for the mitigation gun. Detection of any marine mammal within an exclusion zone shall be recorded and reported weekly, as described in § 217.135(c)(2), to NMFS Office of Protected Resources.

(i) When a requirement for power down or shutdown is triggered, the call for implementation shall be made by the lead PSO on duty and Apache shall comply. Any disagreement with a determination made by the lead PSO on duty shall be discussed after implementation of power down or shutdown, as appropriate.

(ii) Following a power down or shutdown not exceeding ten minutes, Apache shall follow the ramp-up procedure described in paragraph (c)(1) of this section to return to full-power operation.

(iii) Following a shutdown exceeding ten minutes, Apache shall follow the exclusion zone clearance, described in paragraph (b)(3) of this section, and ramp-up procedures, described in paragraph (c)(1) of this section, before returning to full-power operation.

(3) Survey operations may be conducted during low-visibility conditions (e.g., darkness, fog, rain) only when such activity was initiated following proper clearance of the exclusion zone under acceptable observation conditions, as described in paragraph (b)(3) of this section, and there has not been a shutdown exceeding ten minutes. Passive acoustic monitoring is required during all non-daylight hours. Following a shutdown exceeding ten minutes during low-visibility conditions, survey operations must be suspended until the return of good visibility or the use of passive acoustic monitoring must be implemented. Use of a NMFS-approved passive acoustic monitoring scheme, which will be detailed in each LOA, monitored by a trained PSO, will be used to listen for marine mammal vocalizations. If no vocalizations are observed for 30 minutes, Apache may consider the zone clear and commence ramp-up of airguns. During low-visibility conditions, vessel bridge crew must implement shutdown procedures if marine mammals are observed.

(d) Additional mitigation.

(1) The mitigation airgun must be operated at no more than approximately one shot per minute, and use of the gun may not exceed three consecutive hours. Ramp-up may not be used to circumvent the three-hour limitation on mitigation gun usage by returning guns to higher power momentarily and then returning to mitigation airgun.

(2) Apache shall alter speed or course during seismic operations if a marine mammal, based on its position and relative motion, appears likely to enter the relevant exclusion zone and such alteration may result in the animal not entering the zone. If speed or course alteration is not safe or practicable, or if after alteration the marine mammal still appears likely to enter the zone, power down or shutdown must be implemented.

(3) Apache shall not operate airguns within 16 km of the Mean Lower low water (MLLW) line of the Susitna Delta (Beluga River to the Little Susitna River) between April 15 and October 15.

(4) Apache must suspend survey operations if a live marine mammal stranding is reported within a distance of two times the 160dB isopleth of the seismic source vessel coincident to or within 72 hours of survey activities involving the use of airguns, regardless of any suspected cause of the stranding. A live stranding event is defined as a marine mammal found on a beach or shore and unable to return to the water; on a beach or shore and able to return to the water but in apparent need of medical attention; or in the water but unable to return to its natural habitat under its own power or without assistance.

(i) Apache must immediately implement a shutdown of the airgun array upon becoming aware of the live stranding event within 19 km of the seismic array.

(ii) Shutdown procedures shall remain in effect until NMFS determines that all live animals involved in the stranding have left the area (either of their own volition or following responder assistance).

(iii) Within 48 hours of the notification of the live stranding event, Apache must inform NMFS where and when they were operating airguns, beginning 72 hours before the stranding was first observed, and at what discharge volumes.

(iv) Apache must appoint a contact who can be reached at any time for notification of live stranding events. Immediately upon notification of the live stranding event, this person must order the immediate shutdown of the survey operations.