The first of a nationwide series of hearings on the Social Security system took place this week in the hot, half-empty auditorium of George Mason High School in Falls Church.

Presiding was Rep. J. J. Pickle (D-Tex.), chairman of the House subcommittee on Social Security, and Rep. Joseph L. Fisher (D-Va.), a subcommittee member.

About 100 persons attended the public hearing to participate in a discussion on "Women and the Social Security System".

Pickle and Fisher said they came to listen -- and there was plenty to hear. Speakers, young and old, outlined what they said were the many different ways the Social Security system discriminates against women.

At the outset, Pickle told the audience that testimony at the hearings will form a basis for proposing revisions in the system. The changes, Pickle said, could come about as early as 1981.

Most of the speakers prefaced their suggestions or criticisms with remarks about the problems of elderly women in America.

Theresa McKenna, of the Virginia State Council of Senior Citizens, told Pickle and Fisher the most critical problems -- and needs -- are those of elderly, unmarried women.

"They are the poorest segment of society," she said. "Seventy-two percent of all the elderly poor are unmarried women.

"In 1977 the median income of white, elderly, unmarried women was $3,370 and among black, elderly, unmarried women it was $2,480."

McKenna and other speakers said the root of the problem with Social Security is that the philosophy behind it is outdated -- that it amounts to a federally sponsored sexist retirement system.

"The Social Security system as it now exists now guarantees full benefits only to men," said one speaker. "It was established on the faulty assumption that a 'family' consists of one worker and dependents.

"It penalizes women who spend part of their time out of work and caring for their children."

Central to that argument is the history of the system. Social Security was enacted in 1939 -- just before the mass arrival of women in the workplace during World War II. Women stayed on the job after the men returned from war, and have continued to be a major segment of the work force.

"The status of women has changed; Social Security must change in concert," said a representative of the Northern Virginia chapter of the National Organization of Women.

The audience was particularly critical of the way benefits for women are calculated.

Under the present system, benefits are determined on the basis of "average yearly income" during a person's working life. Each person is allowed to exclude the five years in which income was lowest.

Speakers argued that a woman who chose to stay home with her children for more than five years had a zero averaged in for every additional year at home, further reducing her benefits.

Several speakers contended that for Social Security purposes, nonworking women should be allowed to "share" their husbands' incomes on a 50-50 basis during the years they stay home.

Another suggestion would allow a homemaker to declare a given amount of earnings for each year at home. That figure would have to be set by the government.

Speakers pointed out that counting homemakers as bona fide members of the work force would raise the gross national product, since it would recognize the value of their productivity.

The audience also contended that there should be no reduction in benefits for a woman if her husband dies.

"If the husband dies, the wife's benefits go down," said Del. Mary A. Marshall (D-Arlington). "If the wife dies, his go up.

"Some system!" she said emphatically, as the audience roared its approval.

Attention also was drawn to the situation of domestic workers when they retire. Most such workers are women; many have worked irregularly and many have been employed in households where the employer did not pay the woman's Social Security.

No specific solution to the domestic worker problem was offered.

The problem that seemed to plague every proposed solution was cost, as nearly every speaker pleaded with the committee not to cut anyone's benefits because the payments are "meager" as they are.

"When you go to correct one problem you create a set of new ones," said Pickle with resignation.

While there was no consensus on how to revise Social Security, the speakers were unanimous in their opinion that elderly women are not getting a fair deal.

"It seems obvious that our national retirement system is not treating women well," concluded one speaker.