Former spouses of retired members of the Foreign Service have until June 22 to apply for benefits that could give some of them lifetime pensions or survivor benefits worth as much as $15,000 a year.

Federal officials have no idea how many ex-spouses qualify. But they think that many are unaware of the fast-approaching deadline. Many of the ex-spouses -- or people who know how to reach them -- are thought to be in the Washington area. The amount of the benefit due an ex-spouse depends on the length of marriage and the salary their spouse earned in the Foreign Service.

The benefits are payable to men or women who divorced members of the Foreign Service before Feb. 15, 1981. To be eligible for the benefits the former spouse must:

Have been married to the Foreign Service member for at least 10 years while the member was employed by the federal government. Five of those years of marriage must also have been while the member was employed by the Foreign Service.

Not have remarried before age 55.

Apply for benefits to the State Department on or before June 22.

Under special legislation passed by Congress, the benefits that ex-husbands and ex-wives may get will not cost the Foreign Service members anything or reduce their pensions. That information could prompt some people to contact their ex-spouses to urge them to apply.

Former spouses also may be entitled to health insurance coverage at government group rates. Even paying the full premium would be less expensive for most people than trying to buy a comparable insurance policy at individual rates.

For details on the benefits, write the State Department's Retirement Division, Room 1251 NS, Washington, D.C. 20520, or call 647-9315. Remember, the clock is ticking. Minority Youth Jobs

The National Park Service's Conservation Career Development Corps program has earmarked 30 summer jobs for local minority group members and girls who are in junior or senior high school. The minimum-wage positions are designed to give them work, spending money and a possible interest in careers with the Park Service. The jobs run from June 25 through Aug. 17. Call Francis Gipson at 343-5514. Election Called Premature

The National Treasury Employees Union said yesterday's item about a coming election at the Federal Deposit Insurance Corp. was premature. NTEU and its archrival, the American Federation of Government Employees, have each asked for a "unit clarification" at the FDIC. The agency has expanded rapidly, taking in people from agencies caught up in the savings and loan shakeup. Some are treasury union members; some belong to the federation.

The clarification request to the Federal Labor Relations Authority may lead to an election. But no election has been approved or scheduled. Meanwhile, the treasury union said it represents 785 of the 1,100 FDIC workers here.