§ 18.149 Mitigation. ( a ) *Mitigation measures for all LOAs.* The applicant, including all personnel operating under the applicant's authority (or “operators,” including contractors, subcontractors, and representatives) must undertake the following activities to avoid and minimize take of sea otters by harassment. ( 1 ) Implement policies and procedures to avoid interactions with and minimize to the greatest extent practicable adverse impacts on sea otters, their habitat, and the availability of these marine mammals for subsistence uses.
( 2 ) Develop avoidance and minimization policies and procedures, in cooperation with the Service, that include temporal or spatial activity restrictions to be used in response to the presence of sea otters engaged in a biologically significant activity (*e.g.,* resting, feeding, hauling out, mating, or nursing).
( 3 ) Cooperate with the Service's MMM Office and other designated Federal, State, and local agencies to monitor and mitigate the impacts of pile driving and marine construction activities on sea otters.
( 4 ) Allow Service personnel or the Service's designated representative to board project vessels or visit project worksites for the purpose of monitoring impacts to sea otters and subsistence uses of sea otters at any time throughout project activities so long as it is safe to do so.
( 5 ) Designate trained and qualified protected species observers (PSOs) to monitor for the presence of sea otters, initiate mitigation measures, and monitor, record, and report the effects of the activities on sea otters. The applicant is responsible for providing training to PSOs to carry out mitigation and monitoring.
( 6 ) Have an approved mitigation and monitoring plan on file with the Service MMM and onsite that includes the following information: ( i ) The type of activity and where and when the activity will occur (*i.e.,* a summary of the plan of operation);
( ii ) Personnel training policies, procedures, and materials;
( iii ) Site-specific sea otter interaction risk evaluation and mitigation measures;
( iv ) Sea otter avoidance and encounter procedures; and
( v ) Sea otter observation and reporting procedures.
( b ) *Mitigation measures for in-water noise-generating work.* The applicant must carry out the following measures: ( 1 ) Construction activities must be conducted using equipment that generates the lowest practicable levels of underwater sound within the range of frequencies audible to sea otters.
( 2 ) During all pile-installation activities, regardless of predicted sound levels, a physical interaction shutdown zone of 20 meters (m) (66 feet (ft)) must be enforced. If a sea otter enters the shutdown zone, in-water activities must be delayed until either the animal has been visually observed outside the shutdown zone or 15 minutes have elapsed since the last observation time without redetection of the animal.
( 3 ) If the impact driver has been idled for more than 30 minutes, an initial set of three strikes from the impact driver must be delivered at reduced energy, followed by a 1-minute waiting period, before full-powered proofing strikes.
( 4 ) In-water activity must be conducted in daylight. If environmental conditions prevent visual detection of sea otters within the shutdown zone, in-water activities must be stopped until visibility is regained.
( 5 ) All in-water work along the shoreline must be conducted during low tide when the site is dewatered to the maximum extent practicable.
( 6 ) When an impact hammer is used, noise-dampening block cushions or pile caps will be placed between the hammer and pile.
( c ) *Mitigation measures for vessel operations.* Vessel operators must take every precaution to avoid harassment of sea otters when a vessel is operating near these animals. The applicant must carry out the following measures: ( 1 ) Vessels must remain at least 500 m (1,640 ft) from rafts of sea otters unless safety is a factor. Vessels must reduce speed and maintain a distance of 100 m (328 ft) from all sea otters unless safety is a factor.
( 2 ) Vessels must not be operated in such a way as to separate members of a group of sea otters from other members of the group and must avoid alongshore travel in shallow water (<20 m (∼66 ft)) whenever practicable.
( 3 ) When weather conditions require, such as when visibility drops, vessels must adjust speed accordingly to avoid the likelihood of injury to sea otters.
( 4 ) Vessel operators must be provided written guidance for avoiding collisions and minimizing disturbances to sea otters. Guidance will include measures identified in paragraph (c) of this section.