A big chunk of the government's Grade 13 through 15 level workers -- the management and supervisory backbone of the bureaucracy -- will soon lose automatic entitlement to full-sized pay raises each October.

Instead, under the president's civil service reforms, those supervisor-managers will be guaranteed only 50 percent of each regular October pay raise. To earn more than that, they must please their superiors -- both political and career -- who will rate the mid-management bosses through a complicated, and as yet undefined or untried, set of performance appraisals.

The result of the new merit pay system, which also promises big financial rewards for those who do well, will be a more lean, efficient, business-like government, according to optimists. Others say it will give political leaders even more control over day-to-day operations of government, along with their new power over supergraders in Grades 16 through 18.

Some federal agencies will wait until the 1981 deadline to phase in merit pay for their supervisory people. Others have already begun, some by categories of positions, others by grade level or by units within departments. The key will be agency-designed individual appraisal systems, which must be cleared by the Office of Personnel Management, and deciding who is a manager and who a supervisor. That part, at least, has been done.

If you are a manager or supervisor you will, within the next three years, be placed under the merit pay system. And, by federal definition, you are a management official if you have "duties and responsibilities that require or authorize the individual to formulate, determine or influence the policies of the agency." That could take in a lot of people.

Supervisory status is not limited to people who supervise others, or to the size of a staff. The guidelines for it designate a supervisor as an individual who has authority "to hire, direct, assign, promote, reward, transfer, furlough, lay off, recall, suspend, discipline, or remove employes, to adjust their grievances or to effectively recommend such action, if the exercise of the authority is not merely routine or clerical in nature but requires the consistent exercise of independent judgment..."

The more supervisors and managers taken under the merit pay system the greater the control of top political and career officials over the operation. If you do not measure up one year, you get half a pay raise. If that keeps up, you lose your supervisory job, or can be fired.

Under the new guidelines, it appears that thousands of Grade 13 through 15 people -- including some who never thought of themselves as part of the management team -- will be going under merit pay, for better or for worse, for richer or for poorer.

Word Processing: The government's word processing council meets Feb. 23 at the Hospitality House Inn, Crystal City. New developments in the art will be outlined to managers and supervisors in the field. Call Federal Trade Commission's John Uschold at 523-3358 for details or reservations.

Blue Collar Conversions: The House Employe Benefits Subcommittee holds hearings today at the Space Agency's Langley (Va.) Research Center. It hopes to find out what the shift from blue collar to white collar status has done for 1,200 of the NASA workers.

Postal Inspection Service: Richard J. Klenz has been named acting inspector in charge for the Washington Division of the inspection service. It also covers Maryland, Virginia and part of West Virginia. The inspection service is credited with the best conviction rate of any federal law enforcement agency.

Early Out: The special early retirement program for Office of Personnel Management (formerly Civil Service Commission) workers will run through June 30. Under it, staffers can retire if they have at least 20 years federal service and are age 50, or at any age with 25 years service.

Ready For A Tough Year: Staffers in the office of Rep. Gladys N. Spellman (D-Md.) will take a special heart attack identification program next week. The cardiopulmonary resuscitation course is designed to teach individuals to deal with heart attack victims until professional help arrives.