The drive to merge civil service pension systems with social security will go into high gear in January. That is when the nation's nonfederal workers will get their first paycheck reflecting the big, new social security bite. Few are prepared for it.

Currently there are four national-level groups working on some kind of pension reform. All of them appear headed toward recommending merger of the civil service retirement systems - federal, state and local - with social security.

Bakers of the integration say public employes - who enjoy some of the world's best staff retirement programs - ought to join the rest of the American work force, which doesn't do as well under social security. Extra benefits for public service might be allowed, but at an added price to the federal, state and local government workers in many cases.

In addition to all the arguments of the benefits of social security coverage for all, is the political-emotional factor. Many people are convinced that social security would function better if the bureaucrats who manage it also were under it. Added to that is the feeling that federal employes are the national pension pets, getting bigger benefits and earlier retirement than most other workers.

It is impossible to fairly compare civil service and social security. They were set up for different reasons. But comparisons are hard to avoid.

Social security, for example, is not a staff retirement system. Civil service is. Social security payments are lower than civil service pension contributions. So are benefits.

The average person retiring under social security in 1978 is eligible for a $393 monthly payment. For that the individual, according to social security data, paid $6,295.06 during his or her working life. That amount, of course was matched by employers.

The average person retiring under federal civil service in 1977 (latest year available) got a monthly pension of $671. For that the employe - average age 58, average service 25.5 years - contributed $11,613. The government, as employer, matched that amount.

Federal pension contributions are taxable while the employe works. After retirement the annuity is tax-free until the annuitant recovers all he or she paid into the fund. That usually takes about 18 months.

Social security benefits are tax-free. But they are much smaller. With the jolt of the new social security tax bite, the differences will become more apparent.

This January, the social security contribution rate will go up to 6.15 percent on the first $22,900 earned. Since most people earn less than that amount, it means the average worker will be paying social security all year. The current rate is 6.05 percent on the first $17,700.

Because social security contribution costs are nearing the level of costs for civil service - where benefits are much, much higher - there will be a renewed push in Congress to equalize the systems. That is why four major study groups now are working on new financing methods for social security. They are:

The Universal Social Security Coverage Study, under the Department of Health, Education and Welfare.

The Social Security Advisory Council (a group that meets every four years) due to study the problem in 1979. Although only nominally concerned with civil service pensions, it will study the feasibility of mandatory social security coverage for federal, state and local government workers. About half the nation's state and local government employes are under social security. But it is not mandatory.

The National Commission on Social Security, also under HEW.

Presidential Commission on Pension Policy.

Most of the groups will hold public hearings, to find out how federal and private workers, employers, retirees and pressure groups feel about mandatory social security coverage for government workers. Most federal unions, led by postal employe organizations, oppose it. They figure government workers could wind up losing benefits, or paying more, or both, under any merger plan.

The merger question is a multibillion-dollar issue, and one that affects everybody in the nation who pays taxes or expects to retire some day. Decisions made next year willmake major dollar differences in future pensions.

Everybody in the business is waiting for the other shoe to drop. And that will go off with a bang in January when nonfederal workers get their first glance at the new social security price tag.