43 CFR 3809.10 - How does BLM classify operations?
BLM classifies operations as -
(a) Casual use, for which an operator need not notify BLM. (You must reclaim any casual-use disturbance that you create. If your operations do not qualify as casual use, you must submit a notice or plan of operations, whichever is applicable. See §§ 3809.11 and 3809.21.);
(b) Notice-level operations, for which an operator must submit a notice (except for certain suction-dredging operations covered by § 3809.31(b)); and
(c) Plan-level operations, for which an operator must submit a plan of operations and obtain BLM's approval.