Simplify the following text for a Grade 10 native English-speaking person.
Original: After 3 years as a civil servant in the Senate office of the Interior , Wowereit stood for election as municipal councillor in the Tempelhof district .
Simplified: After university Wowereit spent three years as a civil servant in the Senate Office ( that is , Ministry ) of the Interior . At the age of 30 , he was became the youngest councillor in the city of Berlin when he was elected a councillor of Tempelhof Borough .