Firefighters and the Hazardous Materials unit were called Monday morning after the letter was found in the campus mailroom.
Emergency crews were called to the Eppley Administration Building Monday morning after someone found a letter that may have contained a suspicious substance in the mailroom.
As a precaution, the Hazardous Materials Unit came in to investigate. Battalion Chief Paul Kleffner says it turned out that it was sand that was in the envelope.
The building did not have to be evacuated.