Several postal employees of the Indianola mail processing station were put in “moon suits” and removed from the building this morning. Brian O’Keefe, spokesman for the Des Moines Fire Department, says the workers were concerned after finding a suspicious powder on an envelope.O’Keefe says the brown powder ended up being harmless. As mail is run through the machines, tiny bits of paper fiber are sliced off. He says it rained on Friday and a large bunch of those fibers clumped together and stuck to a single envelope.