G. J. "Bud" Manderfield says that his career goal has always been to become president of a billion-dollar bank.

He got his wish last week when he was named president and a director of Suburban Bancorporation, the biggest bank holding company in the Maryland suburbs. Manderfield, currently president and chief executive officer of First American Bank of Maryland, will assume his post July 1.

Manderfield said that his decision to leave First American after four years had little to do with the expected takeover of its parent company, Financial General Bankshares Inc., by a group of investors from the Middle East. "It was not a major issue," he said, saying his decision was based more on the fact that 6 of his 10 children are approaching college age.

"It's (Financial General) going to do well regardless of who owns it if they take advantage of their original charter," he said. The 47-year-old chief executive, who has spent the past 43 years in the Washington area, said he is looking forward to the challenges offered by Suburban, the principal subsidiary of which is Suaburban Trust Co., the largest bank in the District's Maryland suburbs.

"Suburban has positioned itself execptionally well in the marketplace," he said. "It has been an excellent earner and probably has the best branch system anywhere in the suburbs."

Manderfield's strategy is simply to stay "with a well-thought-out game plan, regardless of the foolish endeavors of our competitors, and mobilize the bank staff toward those goals."

Manderfield said also he is looking forward to a close working relationship with the company's chairman, Robert Tardio, who continues as chairman of STC. H. Lee Boatwright III, who is resigning as president of Suburban Trust bank effective later this year, did not hold the position of holding company president to which Manderfield was named. Industry sources said Boatwright, a former Federal Reserve Bank branch head in Baltimore, may be headed back to the Fed.

During Manderfield's years at First American, deposits rose from $187.5 million in 1976 to $247 million at the end of 1979, while net income increased from $405,000 to $2.327 million during that same period.

For an interim period at First American, Robert T. Baker, chairman, has been elected president and chief executive.