Yes you can Michele, Contrary to the popular belive in most cases no license is required as long as the FCC rules are understood, the standards are followed and no interferences are made with any other communications.
In your case, any emergency communications does have priority over all normal traffic on any frequency regardless of any licensing issues.
This would be true only in a declared emergency area for that duration and would not include any simulated events.
In any disaster or time of “declared war” most frequencies are suspended from normal assigned usages and are held open for any priority emergency traffic.
Without getting into any controversial issues with the two different schools of thought on the need to hold a valid FCC issued license, you may wany to read what I posted on this subject matter learned in a federal court room found in the postings on “Expired License”