A New York City real estate firm is making plans to place the first "footprint" next year at Pentagon City, a mini-city south of the Pentagon envisioned 31 years ago by the late developer-builders Morris Cafritz and Charles H. Tompkins.

The 85-acre site, now assessed at some $31 million, is the remainder of 190 acres acquired by Cafritz and Tempkins in 1946 for $1.5 million. It is under contract to Rose Associates, which earlier this year acquired a series of options to develop the tract over a 15-year period.

Under current zoning, the Rose firm can build 1.25 million square feet of office space, 800,000 square fert of retail-commercial space, 2,000 hotel rooms, 5,900 apartment dwellings and other facilities.

Daniel Rose, whose associates are his brothers Frederick and Wlihu, said this week that the immediate goal is to establish a "sense of place" around the strategic Metro station at 12th and South Hayes streets on the Arlington County site, which is just south of Route 1-395 and Army-Navy Drive. Just to the west is the 1,700-unit River House apartment buildings built by Morris Cafritz, who died in the mid-1960s.

The Pentagon City site is also near one section of the vast Crystal City development of office buildings, high-rise apartments and shopping built over the past decade by the Charles E. Smith Commapanies.

Even before the Rose firm begins its work, a 17-acre parcel in the center of the Pentagon City site - acquired earlier by Claridge Associates, headed by Washington developer-builder Maurice Lipnick - is being developed by Lipnick and Richmarr Construction Corp. and Joseph Vucich.

A Lipnick firm, in conjuction with the Virginia Housing Authority, has started at 12-story, 300-unit apartment building for the elderly called Claridge House under the federal government's Section 8 subsidized housing program. The $8 million structure, scheduled for occupancy in the spring of 1979, will have social and dining facilities and a solar-support system for hot water heating.

Nearby, Richmarr is building two-and three-bed-room "town houses over town houses" in four-story buildings. Richard Kirstein of Richmarr said contracts for the first 100 dwellings were signed in three weeks. Since the initial buying surge, prices have been raised and now range between $73,000 and $95,000. Altogether, the Southampton project will indesigned by Cohen, Haft, Holtz Kerxton & Assciates. The firm also designed Claridge House.

On still another part of that tract between 15th and South Hayes streets, developer Vucich has a 200-bed nursing home under way. Vucich built the Carriage House nursing home in Silver Spring.

Rose said that his firm recently reached "an agreement in principle" with the Columbia-based Rouse Co. "to joint-venture a retail shopping facility" at Pentagon City "that is expected to produce the character and exvitement generated by other Rouse shopping centers in major cities."

Rose added that Boston architects Pietro Bellusch: and Yu Sing Jung are in charge of the over-all design. Dewberry, Nealon & Davis, the Northern Virgina firm that did the basic architectural, engineering and planning for the development of the site for the Cafritz-Tompkins estates, will continue to make a contribution to the over-all development, Rose said.

"We want to avoid a collection of odds and ends and operate in such as manner as to establish that anyone getting off at the Metro station in Pentagon City will have a sense of place," he continued.

The retail center is expected to be the first project, followed by a major hotel, headquarters office buildings and then high-rise rental and condo apartments.

Since 1958, Western Electric Co., Inc., has been operating a large service and distribution facility employing about 850 persons in a low-rise building on 13 acres in the center of Pentagon City tract (on 12th Street). Western Electric owns its building and plans to stay there.

The Cafritz Co. has developed and leased 450,000 square feet of low-rise warehouse space in nearby buildings between fern and Eads streets. The land package picked up by the Rose group includes the warehouse area, which undoubtedly will be redeveloped to higher-density use in the future.

The high-density zoning, which was subjected to challenge in recent years, did not clear its final hurdle until September, when the Virginia Supreme Court turned down an appeal on behalf of nearby residents, who were opposed to the additional traffic they expected the complex to generate. CAPTION: Picture 1, Looking north toward Washington and the 14th Street Bridge, this is view of the Arlington site New York company plans to develop into a mini-city, starting next year. By Ken Fell - The Washington Post; Picture 2, The Richmarr Construction firm is building these "town house over town house" units - priced between $73,000 and $95,000 - in four-story buildings located in the center of the planned Pentagon City Complex., By Vanessa R. Barnes - The Washington Post