Field Griffith joined the $38.5 billion Virginia Retirement System, Richmond, as director of real estate investments. He replaces Tom Hassard, the previous director of real estate investments, who retired about a year ago. Mr. Griffith is assisting Charles W. Grant, managing director, who runs the pension fund's real estate investments, said Nancy Everett, chief investment officer. The system has about 3.5% of assets in real estate. Mr. Griffith was executive vice president in the Portland, Maine, office of BGK Properties. Tom Wilson, executive vice president with BGK Properties, assumed a portion of Mr. Griffith's responsibilities, said Eugene Wolkoff, general counsel.