What was going on when I was born?

The Chase Manhattan Bank and 70 other lenders putting together a loan package of as much as $12 billion for the Atlantic Richfield Company are expected to have it ready by today, banking officials said yesterday. The huge line of credit, which would be the biggest ever granted, would clear the way for Arco to proceed with its long-expected bid for the Gulf Corporation, which could involve as much as $13 billion. The bid, which could come early next week, would in turn set in motion the biggest merger deal ever. If the loan package goes through, it would also represent a coup for Chase. Until now Citibank and the Morgan Guaranty Trust Company were regarded as Arco's lead bankers. Making Chase the leader this time is understood to be a reward for past performance over the past two years.

Imagine masses of tiny creatures that not only consume wastes, thus eliminating disposal and pollution problems, but excrete commercially valuable products as well. In effect, living chemical factories. The idea is certainly not new. Fermentation, the process that helps produce cheese and beer, is accomplished by harnessing the digestive process of microorganisms.

In recent speeches, President Reagan has announced a campaign against ''unruly behavior'' in schools. And he has said that improving discipline and reducing school violence will be a key issue during the Presidential election. Such problems do not require increased spending for education, the President has said. Rather, according to Mr. Reagan, proper motivation and leadership from elected and school officials can restore ''good, old-fashioned discipline'' to the schools. Three superintendents from school districts in the New York metropolitan area were invited to discuss these issues this week with Michael Winerip of The New York Times. The superintendents are Dr. Joan Raymond of Yonkers, an urban district with a large number of low-income students; Dr. Robert Ricken, of Mineola, L.I., a middle-class suburban district, and Dr. Samuel B. Stewart, of Ridgewood, N.J., an upper-middle-class community in Bergen County.

FRIDAY, MARCH 2, 1984 The Economy The House Ways and Means Committee approved tax increases of $50 billion over four years, including additional revenues from liquor, cigarettes and telephones. Both chambers of Congress are trying to reduce Federal budget deficits. The Senate Finance Committee voted to stretch out depreciation on buildings and to limit write-offs on cars used for business. (Page A1.) Paul A. Volcker said huge deficits were ''a loaded gun'' threatening recovery. (D4.)

Friday CAESAR' IN WASHINGTON Political handbills urging the nomination of Caesar for king in 1984 will be distributed at 165 West 86th Street, at Amsterdam Avenue, tonight at 8, when the Riverside Shakespeare Company offers ''The Tragedy of Julius Caesar'' as a Presidential tale. It's set in Washington with modern dress and guns instead of knives. But the text, while cut somewhat, is all Shakespeare, except for a few word substitutions: ''patriot'' for ''Roman,'' for instance. (The playwright's references to the Senate and senators fit right in.) The director and adaptor is W. Stuart McDowell, artistic director of the company. Tickets: $8. Chargit: 944-9300. Information: 877-6810. MIHAESCO ON 57TH STREET Eug ene Mihaesco, the Rumanian-born illustrator, whose lyrical city scenes and acerbic drawings reflecting modern angst have appeared in such publications as The New York Times and The New Yorker, is the subject of an exhibition called ''The Illustrator as Artist,'' at the Galerie St. Etienne, 24 West 57th Street. The show surveys Mihaesco's latest work, from preliminary study to finished piece. ''The looser, more intimate approach of his latest pastels,'' the gallery notes, contrasts with his ''meticulous pen-and-ink drawings of former years.'' Admission is free. Hours: 11 A.M. to 5 P.M., Tuesdays through Saturdays; Mondays, by appointment. Information: 245-6734. Saturday LUBOVITCH DANCERS ON L.I.

The Senate by a voice vote tonight approved a bill giving the President greater authority to halt exports of sensitive products and technology to the Soviet Union and other countries found to be undermining American national security or foreign policy goals. The Senate completed its version of the controversial legislation to revamp the expiring Export Administration Act with passage of a bill sponsored by Senator Jake Garn, Republican of Utah, chairman of the Senate Banking Committee, and Senator John Heinz, Republican of Pennsylvania. ''This has been a marathon,'' commented Senator John Heinz, Republican of Pennsylvania, after the vote late tonight. Senator William Proxmire, Democrat of Wisconsin, added, ''This is as tough a bill as I've seen in a long, long time.''

A 39-year-old man who officials say was about to be removed from his Brooklyn teaching job was charged yesterday with killing a young woman by shoving her into the path of a subway train. The police said witnesses told them that the suspect - John Cardinale of 60-39 Madison Street in Ridgewood, Queens - muttered ''push, push, push'' and shouted obscenities about the Board of Education before knocking the woman onto the tracks Wednesday evening. According to the police, he shoved the woman, who was standing near the edge of the platform, in front of a northbound No. 6 IRT train at the Canal Street station. The incident occurred at 5:15 P.M. The police said Mr. Cardinale did not know the woman, who was identified as Ly Yung Chung, 19 years old, who arrived in the United States from China four months ago. As the train ran over the woman, the man was heard to say, ''Now, we're even,'' according to the police.

The House Ways and Means Committee today approved $49.3 billion in tax increases over the next four years, including additional revenues from liquor, cigarettes and telephones. The committee, meeting behind closed doors, drafted a bill that will be an important part of the House's contribution to the effort in both chambers of Congress to reduce the Federal budget deficit. Although details of the committee's bill are subject to change on the House floor and in conference with the Senate, its main elements are expected to be part of the legislation that will go to President Reagan. Goal of $50 Billion Working an unusually long day, the committee met at 9 A.M. and sat until just before midnight in an effort to achieve the goal of its chairman, Representative Dan Rostenkowski, Democrat of Illinois, to produce $50 billion in new revenues. As the committee adjourned late tonight, Mr. Rostenkowski said the bill ''rests on solid bipartisan footing'' and is ''a first installment on an ever-increasing debt.''

The Environmental Protection Agency indicated today that it would seek to bar New York City and other municipalities from dumping sewage sludge 12 miles off the New Jersey coast. The agency indicated that it would designate a new dump site 106 miles at sea off the continental shelf. Jack E. Raven, assistant administrator for water of the E.P.A., told the House Oceanography and Fisheries Subcommittees that the 12-mile site, in use since 1924, was ''degraded.'' He called the 106-mile site ''much more dispersive'' and said that ''dispersion seems a better answer for sewage sludge.''

''We're in for a long, tough fight that could well go to the convention.'' - Walter F. Mondale. (A1:2.)

The bitter fight for the Gulf Oil Corporation has backfired for one group of the oil company's pursuers, the wealthy Belzberg brothers of Canada. An attempt by the Belzbergs - allied with Mesa Petroleum's T. Boone Pickens in a bid for control of Gulf - to buy all the remaining shares of a southern California thrift institution they already control was scuttled today when Bear, Stearns & Company said the bid was too low. The offer was insufficient because the value of the thrift institution, the Far West Financial Corporation, had risen by more than $6 a share since the Belzbergs' bid was made in December. That is because the value of Far West's stake in Gulf, at 495,895 shares, has skyrocketed as the Gulf shares increased from the low $40's to almost $70 during the Mesa group's play for the large oil company.

Senator Ernest F. Hollings and former Gov. Reubin Askew withdrew from the Democratic Presidential campaign today, narrowing the field of major contenders for the nomination to five. At the same time, Walter F. Mondale said he no longer considered himself the front-runner in the race as a result of Senator Gary Hart's upset victory on Tuesday in the New Hampshire primary. ''We're in for a long, tough fight that could well go to the convention,'' the former Vice President said in Washington. ''It is clearly a two-man race and it is very close.''