Last Wednesday, Metro put out a press release. It said:

"Twenty-five of Washington's best Metrobus operators will compete in the transit authority's first annual bus rodeo beginning at 9:30 a.m. Saturday, July 29, at the RFK Stadium parking lot." First prize: $1,000.

At Metro, last Wednesday was notable for more than the distribution of that press release. It was also payday. It was the day operators learned they weren't going to get a wage increase of 20 cents an hour until they agreed to a new contract. It was the day the strike began.

The good-natured intramural rivalry that had existed among Metro's top bus drivers was suddenly washed away by more pressing business. Interest shifted from 25 operators scheduled to drive in a "roadeo" to 4,800 men and women who wondered when or if they would ever drive for Metro again. By law, drivers who strike against Metro can be fired.

The operators have been without a contract since their old agreement expires on April 30. Union and management have been talking since then, but have made no visible progress on one key issue: part-timers.

Part-timers? Was the part-timer issue important enough to knock out mass transit in the nation's capital? Apparently it was. And is.

People use the term "part-timer" to describe several types of jobholders.Sometimes a so-called part-timer is really a full-timer - a person who works a full shift, but not on a permanent basis. For example, during the summer, when regular employes are on vacation, a firm will hire extra help to fill the gaps.The people they hire work a full day. They are really temporary full-timers rather than part-timers.

Part-timer is perhaps more accurately applied to one who works a short shift on a given job - either regularly or irregularly. Small wonder that at times there is disagreement and confusion as to what constitutes a part-timer.

One can be a permanent full-timer or a temporary full-timer; and one can be a permanent part-timer or a temporary part-timer.

Let me illustrate. A person with a full-time job might "moonlight" by working a few hours on a second job. He might do his moonlighting all year around, confine it to certain seasons, or work sporadically, subject to an employer's call.

A housewife might be available to work from 10 a.m. to 2 p.m., but not before 10 or after 2 because she has more important responsibilities to her family. She, too, could be a regular part-timer, a seasonal worker or one who is subject to call.

An elderly or semi-retired person might not want more than a few hours of work per day. For one reason or another, many people welcome short-shift work. And many employers welcome short-shift workers for economic reasons.

Transit managements want the right to hire part-timers because mass transit's peak need for personnel is brief: two or three hours in the morning and two or three hours in the evening. If Metro can hire - and pay for - only the labor it needs, it can save a lot of money. As staff writer Douglas B. Feaver told us in his perceptive articles about contract negotiations, Metro management says, "Many drivers do 6 1/2 hours of productive work and are paid for 8 hours or 9 hours."

Union officials are, however, traditionally opposed to permitting part-timers to be brought in. Few industries give part-timers the fringe benefits enjoyed by full-time personnel. Some industries don't even require part-timers to join the union. When a company can cover a short shift with a part-timer, it avoids paying overtime rates to a regular employe.

What it boils down to is that Metro wants to be able to meet some of its peak needs with part-timers at $8.36 an hour instead of with regular employes on overtime - at $12.54 an hour.

I can't blame Metro for trying to cut costs. I can't blame union leaders for trying to keep the goodies for their present members. I'm just glad I'm not an arbitrator.

The reason we had a strike is that the drivers' labor contract expired. One reason no new contract has been agreed to is that Metro doesn't want to pay out the 20-cent cost-of-living increase until it gets some concessions on part-timers. Metro wants the two issues included in a package. The drivers want the 20 cents paid now while they continue to stand fast on part-timers and other issues. As they say in the Middle East, somebody is going to have to yield.