As a member of the Kansas City Cosa Nostra organization, Impastato became known primarily for his role as a go-between with the KC and Tampa, Florida crime families.
He was sent to Tampa in 1939, probably at the behest of KC mob boss Charles Binaggio to coordinate the transfer of heroin between the two cities.
Impastato interacted with the Antinori's, prominent members of the Tampa family, which was led at the time by James Lumia.
It was believed that Impastato and his cohort James DeSimone also performed various enforcement tasks for the Tampa family.
They conducted raids on a bar at Armour and Troost, and at the residence of Felipo Pernice at 425 S. Montgall in Kansas City, where they seized heroin secreted in coffee bags that had been hidden in a compartment in the basement of the house.