Five developers will begin bidding today for land atop the Metro Center subway station - a piece of downtown Washington real estate that only two years ago was considered a marginal site for commercial construction.

Within the past week, the city's Redevelopment Land Agency has received proposals from developers willing to spend $150 million to $350 million to build a massive retail-office-residential complex on the land along G Street NW.

RLA owns the whole north side of G Street from 11th Street NW, west to the Church of the Epiphany, between 13th and 14th Streets. Also available is the southwest corner of 13th and G Streets NW.

When Texas developer Gerald Hines offered to buy the property from RLA in 1975, he said building on the site was possible only with government subsidies.

"Current evidence suggests that the downtown area east of 15th Street will not support quality office development without government assistance," Hines warned in a memo of understanding with the District Building.

"Government assistance" turned out to mean a 20-year, $3-million-a-year lease for District of Columbia government offices in the complex Hines planned to build. When the $60 million subsidy fell through, so did Hines' plan.

Last March, after several extensions, Hines gave up his right to the site, leaving some downtown watchers fearful that the land would remain underutilized.

But Developer Oliver T. Carr Jr. quickly added Metro Center to the list of things he wants to build.Offering to take up where Hines left off, Carr said development of the site is "feasible and practical and there is no need for federal or city subsidies."

[WORDS ILLEGIBLE] to be in for tough competition for the right to adopt the orphan real estate. RLA will hold hearings today to give him and two other developers a chance to make their pitch. Two more companies have until June 26 to submit proposals.

RLA is expected to give at least one of the developers what amounts to an option on the land until a final development plan is prepared. Then the developer can buy or lease the tract and start building. The decision will be based on the developer's ideas and ability to accomplish them, not just on how much he'll pay for the property.

Carr's chief rival for the job is Western Development Corp., a Georgetown company headed by Herbert Miller. Miller has caught the ear of RLA officials by dropping the names of Rockefeller, Pei and the D.C. Chamber of Commerce.

Western's partners in the joint venture would be Earnest Hahn Construction, a California firm that has built several downtown renewal projects; and Rockefeller Center Inc., which owns Tishman Construction and Research, a major New York builder and Cushman & Wakefield, one of the biggest office real estate firms on the East Coast. The architectural consultant would be I.M. Pei, designer of the widely acclaimed new East wing of the National Gallery of Art.

But the most impressive names Miller has mentioned are the D.C. Chamber of Commerce and the District of Columbia Development Corp. (DCDC).

The D.C. chamber and DCDC would bring minority merchants into the project, by providing financing and other assistance so that minority firms could lease at least 15 percent of the stores in the complex.

Western Development's proposal jalls for a downtown shopping mall, with a million square feet of retail space and two or three major department stores. In addition, there would be a 350-room hotel, about that many apartments and about a million square feet of offices.

Bethesda builder Nathan Landow also will meet with RLA officials today, although he has not made specific proposals for the land. Other offers are expected from Blake Construction Co. and a group of businessmen and lawyers interested only in the tract at the southwest corner of 12th and G. The group includes Manuel Fernandez, Wylie Powell, Donald Brown, Joseph Gildenhorn and Ben R. Jacobs.

Why are so many developers interested in land that two years ago was considered useful only for government-subsidized construction?

One explanation, from RLA's real estate specialist, Joyce Cappon, is that "we've run out of land west of 15th Street. The whole West End is under Carr's control, just about everything else is taken and we've run out of office space, so we're turning to the east.

"Even before the convention center was approved, this was the only direction they had to go."

Developer Miller said there are several factors making the site more attractive, particularly for a major retail project.

"In-town retail developments have proven they can work financially," he explained. "The office market here is extremely strong, at the peak of a cycle. Metro has proven itself as a functioning contribution to the community and Pennsylvania Avenue is starting to happen. The time is ripe for that part of downtown."