Bart R. Mueller is stepping down as executive director of the South Jersey Transportation Authority, the state agency that operates the Atlantic City Expressway and the Atlantic City International Airport.

His resignation is effective July 1, the SJTA said in a statement.

Mueller, of Oaklyn, Camden County, has been executive director of the SJTA since 2007, a period marked by an expansion at the Airport, including a modern parking facility.

During Mueller's tenure, the number of passengers using the airport has increased by almost 50 percent to 1.4 million annually as of last year, the statement said.

The agency said Mueller was leaving to pursue other business opportunities.