What is the test for determining whether the use of a jackhammer to search beneath a concrete slab was unreasonable?

Turning to the merits of the case, the issue is whether the use of a jackhammer to search beneath the concrete slab was unreasonable. "A warranted search is unreasonable if it exceeds in scope or intensity the terms of the warrant." United States v. Penn, 647 F.2d 876, 882 n. 7 (9th Cir.) (en banc), cert. denied, 449 U.S. 903, 101 S.Ct. 276, 66 L.Ed.2d 134 (1980). Whether officers exceeded the scope of a warrant during a search is reviewed de novo. See United States v. McLaughlin, 851 F.2d 283, 286 (9th Cir.1988). The question of unreasonable intensity can only be resolved by reviewing the facts and circumstances of each case. See Penn, 647 F.2d at 883. Upon review, we conclude that the agents' search did not violate the scope of the warrant nor was it unreasonably intensive.