The Montgomery County Council, in the midst of a heated debate over the fast pace of development in the Maryland suburban area, last week voted unanimously to appoint a former New York City development official to the post of director of the Office of Economic Development.

L. James Eaton, 42, formerly director of industrial development for Queens County in New York and a development consultant for Long Island and New York City, will face his first test in the sometimes bitter struggle over unsnarling the traffic congestion that has plagued the county as a result of its unprecedented growth.

With a staff of 22 employes and an annual budget of $1.7 million, Eaton will direct the county's efforts "to encourage balanced economic growth," according to a statement by the Montgomery County government. As director of economic development, Eaton will act as a "facilitator" between business and government and will attempt to encourage both new and existing business and will try to improve employment opportunities, he said in an interview.

Eaton succeeds Ioanna T. Morfessis, who resigned in June after seven years as director of economic development to become executive director of the Phoenix Economic Growth Corp. in Arizona.

The Office of Economic Development recently reported that many businesses have expressed concerns about traffic congestion in the county and that some have moved away or decided not to locate in the county. Builders and development professionals also have expressed concern that businesses are looking elsewhere to build.

Earlier this month, the County Council, by a vote of 4 to 3, sent back to the drawing board a proposal by members David Scull and Neal Potter to limit development by placing a three-year cap on building permits.

In contrast, County Executive Charles Gilchrist, who nominated Eaton for the $61,000-a-year position, has proposed a six-year, $275 million road construction program designed to keep up with the pace of development and provide enough capacity for development until the end of the century.

In an interview, Eaton said he is against any solution to the problem that would impose restrictions on development, such as the Scull/Potter proposal, and would rather see the county solve the problem by building new roads and improving existing ones.

Eaton said that although this devisive debate "makes the job a little harder, in the long run, it might make the job easier if the problem is solved in a way that makes the area continue to be conducive to business." PROFESSIONAL SERVICES

The parent company of Ringling Bros. and Barnum & Bailey Circus, Washington-based Irvin Feld and Kenneth Feld Productions Inc., has appointed Allen B. Flexer to the new position of vice president in charge of developing new business ventures. Flexer was president of Spectator Management Inc., a Philadelphia-based management firm that operates the Spectrum in Philadelphia and the Coliseum in Richmond, among other properties.

Swanke Hayden Connell Architects has appointed Margaret Ritchie Axtell projects director in the national architectural firm's Washington office. She was with Arthur Cotton Moore Architects, Wilkes and Faulkner and had her own private practice.

Katherine Gibbs School Inc. has named Linda Hamner Cunningham director of its school in Tysons Corner. She served as admissions director at the Gibbs school in Norwalk, Conn., for the past two years.

Arthur Young & Co., an international accounting firm, has appointed Rhoda W. Canter and David H. Haedicke partners in its Washington office. Canter, a graduate of Georgetown University and formerly assistant director of Law Search Inc., will work in the management and information technology center. Haedicke, who joined the Washington office in 1981 after stints in Atlanta, Detroit and London, will become a partner in the Washington audit practice. The firm also named six new principals: John L. Baines, Thomas P. Edgar, John J. Farrel, Diane C. Hately, Mary W. Hishmeh and Michael J. Loyco. BANKING, FINANCIAL

Security National Bank recently announced new officers: David G. Fleming, who joined the Washington bank from American Security Bank in 1981, was elected executive vice president and senior lending officer. M. Stephen Cates, an accountant and former state bank examiner in Virginia, was named senior vice president and chief financial officer. Susan G. Riel, a former branch administrator, was promoted to senior vice president for human resources and security officer. Virginia L. Travers, formerly with the Eastern Branch office, was named assistant cashier. Charles E. Calandra, formerly with Riggs National Bank, was appointed vice president and a branch administrator.

Capital Bank has appointed two officers: Charles F. Koehler, a former vice president of New York-based Citibank, was tapped as senior vice president in charge of all lending. Frank Thompson, formerly comptroller of Madison National Bank, has been named vice president, controller and chief financial officer.

Directors of Perpetual American Bank, the largest federally-insured savings bank based in the Washington region, have elected Mark J. Riedy to a three-year term as a member of the bank's board. Riedy is president and chief operating officer of the Federal National Mortgage Association, the congressionally chartered corporation that provides a secondary market for residential mortgages.

The Bank of Alexandria has appointed Alphus E. Arthur vice president and senior loan officer of the bank. Arthur, formerly vice president and regional loan officer for Equitable Bank in Montgomery County, will have responsibility for the bank's commercial loan program.

United Virginia Bank announced recent promotions in its professional and executive division, which caters to professional firms and senior company executives. Joseph L. Schwarzmann, previously vice president, has been named senior vice president and manager of the division. Owen Magruder Jones, who recently joined the firm from First Federal Savings and Loan Association of Northern Virginia, has been appointed vice president in charge of lending for the division in Alexandria. And Larry E. Jenkins, an 18-year veteran of UVB, has been named assistant vice president with responsibility in Springfield. COMMUNICATIONS

Geostar Corp. has announced a series of senior-level promotions, which the 3-year-old satellite communications firm says marks its graduation from the development stage to an operating company. The announcement by the Princeton, N.J.-based firm included appointments in its Washington office, which handles government and international marketing and legal regulatory affairs. Martin A. Rothblatt, formerly vice president for business and regulatory affairs, will become president and chief operating officer, succeeding Gerard K. O'Neill, who will remain chairman and chief executive officer. Michael J. Breslin, formerly vice president for marketing, will become executive vice president, retaining his marketing duties. And T. Stephen Cheston, a former dean of Georgetown University Graduate School, will become vice president for governmental affairs.

Malarkey-Taylor Associates, a Washington-based cable television consulting firm, has made several recent appointments. Robert M. Jones, formerly vice president for finance, has been promoted to executive vice president and chief operating officer. Clark T. Madigan, a former group vice president at American Security Bank, has joined the firm as vice president for corporate finance, with responsibility for long-term financial planning. Roy E. Hayes Jr., formerly president of Amcom Realty Corp., has been named vice president for investment services. He will oversee mergers and acquisitions and other corporate restructuring. Laura A. Flieger has been promoted to assistant controller. RETAIL, WHOLESALE TRADE

Giant Food Inc., which operates 134 stores in Virginia, Maryland and the District, has announced two promotions: Michael J. Bush, formerly legal counsel in the real estate department, has been named vice president for real estate. In the new job, he will oversee the chain's efforts to obtain new store locations, administer existing leases and arrange real estate financing. Stephen L. Oseroff, who has been director of real estate since 1979, has been appointed vice president for shopping centers. He will supervise land acquisition and development, as well as leasing and promotion of shopping centers and property management. Bush and Oseroff also will retain their posts as vice presidents of GFS Realty Inc., which owns and manages shopping centers.