They are looking as far as necessary to establish an immediate risk level. If there is a sealed bulkhead and it's not going anywhere, they will not poke around just for fun.That's strange because the article referenced elsewhere did not indicate this.
It seemed to indicate that the US military was looking for the presence of nuke/chem/bio at those sites.
Of course, this might not contradict your claim of "risk level", but it does say that the "risk level" they have found is "no nuke/chem/bio weapons found".
Strange how that works.
They aren't going to "poke around" but they are able to establish that there aren't any nuke/chem/bio weapons.