§ 216.215 - 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 above the water-mud interface, 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 determine the appropriate marine mammal mitigation/monitoring measures.

(b) Terms (1) Impact zone (required for all scenarios) means the area around a decommissioning target measured by the horizontal radius, in which a marine mammal could be affected by the pressure or acoustic energy released during the detonation of an explosive-severance charge.

(2) Predetonation survey (required for all scenarios) 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) means any marine mammal monitoring survey (e.g., surface, aerial, or post-post-detonation aerial) conducted after the detonation event occurs.

(4) Waiting period (required for all scenarios) means the amount of time detonation operations must hold before the requisite monitoring survey(s) can be repeated.

(5) Company observer (for scenarios A1–A4 only) means trained company observers authorized to perform marine mammal detection surveys only for “very-small” blasting scenarios A1–A4.

(6) NMFS observer (for scenarios B1–E4) means observers trained and approved by an instructor with experience as a NMFS Platform Removal Observer Program trainer. NMFS observers are required to perform marine mammal detection surveys for all detonation scenarios with the exception of scenarios A1–A4. Two NMFS observers will be assigned to each operation for detection survey duties, except mitigation-scenarios C2, C4, D2, D4, E2, and E4 require a minimum of three NMFS observers for the simultaneous surface, aerial, and acoustic surveys.

(c) Criteria —(1) Blasting category parameters and associated severance scenarios. To determine the appropriate marine mammal mitigation and monitoring requirements in §§216.218 and 216.219, holders of Letters of Authorization for activities described in §216.211(a) of this subpart must determine, from Table 1 in §216.217(b)(1), the appropriate explosive severance mitigation/monitoring scenario to follow for the blasting category, species-delineation zone, and charge configuration for their activity.

(2) [Reserved]