43 C.F.R. § 3836.20 Deferring assessment work.
Title 43 - Public Lands: Interior
(a) Under some circumstances, you may obtain a temporary deferment that relieves you from performing annual assessment work on your mining claims. You may include more than one mining claim in one deferment petition if the claims are contiguous. (b) If BLM grants you a deferment, you have merely deferred doing the assessment work. You still must complete that assessment work for that assessment year after the deferment period ends, as provided in §3836.27.
Title 43: Public Lands: Interior
PART 3836—ANNUAL ASSESSMENT WORK REQUIREMENTS FOR MINING CLAIMS
Subpart B—Deferring Assessment Work
§ 3836.20 Deferring assessment work.