White House officials and congressional leaders are meeting again today in search of a compromise pension plan for the 300,000 federal and postal workers hired since January 1984.

An interim pension-financing system expired May 1, and those workers have been paying an extra 5.7 percent of salary to cover contributions to the civil service retirement fund. Prior to May, the new hires put in only 1.3 percent for retirement coverage. Workers hired before 1984 contribute at least 7 percent of their salaries into the federal pension plan.

In late April, the Senate and House had tentatively agreed to a new retirement system. It would have based benefits on Social Security, a modified civil service pension and earnings from a voluntary, tax-deferred investment plan. But the White House balked at the compromise, saying it was too costly and contained unacceptable early retirement features.

The White House asked for an additional 30 days to negotiate an agreement, but Senate and House leaders refused to go along. When the old financing system expired, the new, higher pension contributions went into effect for those employes.

When and if a new retirement system is set up, the extra contributions that the new employes are now making to the civil service program may be refunded. In the meantime, they will make full payments to both Social Security and the civil service retirement fund amounting to nearly 15 percent of salary. Early Retirement

Senate hearings start Thursday on a plan to allow thousands of workers to take early retirement between July 1 and Dec. 31. The bill, by Sens. William V. Roth Jr. (R-Del.) and Ted Stevens (R-Alaska), would waive current age and service requirements and allow an additional 200,000 workers to retire.

Saturday afternoon, from 1 to 2 p.m., Dick Schreitmueller of the Senate Governmental Affairs Committee staff will talk about the early retirement plan on WNTR (1050 AM) radio. He'll explain the purpose of the bill and penalties involved, and will answer listeners' questions. Mailing Lists

U.S. District Court Judge Joyce Hens Green has ruled that the Office of Personnel Management should provide home addresses of retirees to the National Association of Retired Federal Employees.

NARFE, which has more than 500,000 members, had asked OPM for addresses of people who retired in 1981 through 1984. OPM refused, saying that would be an invasion of privacy. NARFE officials said the old Civil Service Commission routinely provided names and home addresses of retirees. Jobs

Federal Deposit Insurance Corp. needs a visual information specialist, GS 7/9. Civil service status required. Call 898-3878.

Army's Corps of Engineers wants a GS 4 housing clerk, a GS 5/7 secretary (steno), and electrical and mechanical engineers, GS 12. Call Gwen Brown at 272-0365. People

D. Jamison Cain, who helped sell the nation on the usefulness of zip codes, is retiring this month after 25 years with the U.S. Postal Service, where he is director of news and public affairs. Before joining the old Post Office Department, Cain worked as a reporter in South Carolina and a Washington correspondent for South Carolina newspapers.

Edward T. Rhodes, Office of Personnel Management's deputy director for Administration is leaving to take a top procurement job with Metro.