Eight Washington-area developers have submitted "in-concept" proposals to build an office and residential complex on a six-acre plot of land near the Court House Metro station in Arlington, Arlington County development officials report. The county-owned parcel was offered for development a month ago.

The complex would be located in what is now largely a parking area adjacent to the Metro stop between north 15th and 14th streets. It could contain as much as 470,000 square feet of office space and is required by county specifications to include at least 440 residential units. Construction would begin no earlier than summer of 1983, county planners said.

The complex--residential portions of which could go as high as 16 stories and could cost upwards up $100 million--must also include retail space and about 30,000 square feet for a community meeting center or for county offices.

In about 60 days, a seven-member panel of citizens, county officials and out-of-town professionals will select three finalists from the list of firms and ask them to submit detailed plans for the complex.

The applicants are the Charles E. Smith Companies; the Mobil Land Development Corp. of Reston, the Quad Group of America, Inc., of Hyattsville, New York developer Alfred Ginsburg, who currently is building a 12-story office building south of the new site; a three-way partnership of the Fairmac Realty Corp. of Arlington, the Sigal Development Corp. and Shelton Zuckerman Associates, Inc., both of Washington; a partnership of Washington developers, the Holladay Corp. and the Kaempfer Co., and a partnership of the Lincoln Property Company of Washington and the Bethesda-based Frank S. Phillips Companies.