There are two types of assessment procedures:

(a) Type A procedures are simplified procedures that require minimal field observation. Subpart D describes the type A procedures. There are two type A procedures: a procedure for coastal or marine environments, which incorporates the Natural Resource Damage Assessment Model for Coastal and Marine Environments, Version 2.51 (NRDAM/CME); and a procedure for Great Lakes environments, which incorporates the Natural Resource Damage Assessment Model for Great Lakes Environments, Version 1.51 (NRDAM/GLE).

(b) Type B procedures require more extensive field observation than the type A procedures. Subpart E describes the type B procedures.