The Department of Health, Education and Welfare is drafting two pathbreaking plans for study by Congress on ways to bolster Social Security protection for women.

The problem is that, while many women now hold paying jobs and earn Social Security credits on their own, millions still stay home to take care of children, or hold outside jobs intermittently.

As a result, many never earn the right to such valuable benefits as disability insurance. Many are also completely dependent on their husband's earnings record for the right to a wife's or widow's Social Security pension -- and may lose eligibility in case of divorce.

The plans being drawn up by HEW would give such women eligibility for many Social Security benefits in their own right.

One plan would allow a couple to split their earnings records for Social Security benefit purposes, even if the man worked full-time and earned all the money while the woman stayed home and took care of the children. Thus, if the husband earned $1,000 one month and the wife nothing, each would get credit for $500 in earnings. This would give a woman an independent earnings record, so that she could draw benefits in her own right even if she never worked. At present such a woman can obtain old-age benefits only if her husband retires on Social Security and she gets the wife's benefit (equal to an extra 50 percent of her husband's benefit) or if she is widowed.

The second plan would be to revise Social Security into a "double-decker" system, consisting of two separate tiers of benefits. The first tier would consist of a flat government payment equal to $120 or $130 a month, given to every citizen reaching retirement age whether they worked or not. On top of that, individuals working under Social Security-covered jobs for the required number of years would get a wage-related benefit of up to $3,600 a year or so, depending on wages. Thus a wife, or a widow or nonworking woman who had stayed at home, for example, to take care of a father or brother, or who had been ill, would be guaranteed some benefit -- the $120-a-month first tier.

Under both plans -- which are being submitted only for congressional study -- the current 50 percent wife's benefit would be eliminated. Women would have entitlements on their own right and wouldn't need the extra benefit.

These proposals are being submitted to Congress because it asked HEW to study various ideas on how to improve women's benefits. HEW isn't formally endorsing either plan.

The income-splitting and doubledecker proposals are seen as two ways of achieving the same objective: to give women benefit entitlements of their own, not dependent on marriage, not lost in case of divorce, and based on the concept that to stay home and be a homemaker, caring for children, is as valuable a contribution to a family's welfare as working outside the home.

In recent years, Social Security has come under increasing attack from women's groups for being a benefit structure that, some say, penalizes a woamn who stays home to take care of her children while her husband works, or who remains at home to care for other relatives.

Well over half of all women between 16 and 65 are now in the labor force. Women's groups say that a woman who takes a few years off for child-bearing may interrupt her employment record and entitle her to lower benefits or no benefits except a wife's or widow's benefit based on a husband's earnings record -- and even this can be lost if divorce ended the marriage before 10 years.

Last week, at hearings before the Social Security Advisory Council, these criticisms were made of the system as it affects women's benefits:

Women who stay home to care for their children may earn so few Social Security credits that they are never eligible for the valuable disability benefits available to a disabled young worker.

They may also never earn enough credits to get retirement benefits in their own right.

Even if they do, the intermittent character of their work and the fact that they tend to be paid less than men means their benefit payments will be smaller -- in fact, some 1.6 million elderly women today who are entitled to their own benefits take a wife's benefit instead because it is higher. Many women in this latter group resent the fact that while they have been paying Social Security taxes, they get benefits lower or little better than if they didn't work at all and took a wife's benefit.

The income-splitting or alternatively the two-tier system would solve many of these problems. The specifics are being formulated in such a way that they wouldn't add substantially to present program costs -- a key factor

The way the income-splitting plan is drafted, each partner in the hypothetical $1,000-a-month couple would end up in retirement with a monthly benefit of $272, or $544 combined.

Under existing law, a man retiring on a $1,000-a-month earnings record all his own would get $432, but an extra $216 (for a total of $648) if he had a dependent wife without any earnings record. Thus, in order to give the woman her own earnings record and eligibility for disability, the plan might mean a reduction in final retirement income for a couple as compared with now. It's a tradeoff.

Another feature that HEW is considering putting into either plan is to give a widow who has no career or training (for instance, one who was 55 when widowed and had never worked) a one-year living and training allowance to allow her to get back into the labor force until she reaches 62 and becomes eligible for old-age benefits.

To help pay for the allowance, the proposal would raise the minimum retirement age for widows to 62, instead of the present 60.