What was going on when I was born?

Rita M. Lavelle, former head of the Environmental Protection Agency's toxic waste cleanup program, was indicted today by a Federal grand jury for contempt of Congress. The indictment charged that after being served with a subpoena, she ''wilfully'' refused to appear to testify March 21 before a House subcommittee investigating allegations of wrongdoing at the agency. If convicted of the charge, a misdemeanor, she could be imprisoned for up to one year and fined up to $1,000. The indictment grew out of a unanimous vote in the House of Representatives last week citing Miss Lavelle for contempt. She is the first person indicted in the controversy that since February has resulted in the resignations of more than a dozen of President Reagan's senior appointees to the environmental agency.

A Puerto Rican terrorist who escaped from a hospital prison ward in New York City in 1979 was recaptured in Mexico Thursday, lawenforcement officials in New York said yesterday. Two people were killed and three wounded in gun battles with the Mexican Federal police after the capture, the officials said. The terrorist, William Morales, had lost his hands and was nearly blinded in the left eye when a bomb he was making exploded in a Queens apartment in 1978. In one gun battle Thursday, the officials said, two police officers were wounded, one critically, and one of two companions arrested with Mr. Morales was killed after a car sped up alongside a police car carrying the captives.

President Reagan arrived here today for the economic summit conference after insisting that his strategy for dealing with continuing high budget deficits would not aggravate world economic problems. Asked before he departed from Washington whether he expected pressure on this point from other summit participants, Mr. Reagan said he was ''quite sure'' they would question him about domestic budget plans. ''Since our plan is working,'' he added, ''I don't care what the pessimists say and what the opponents say about it.'' The deficits are expected to draw strong criticism at the conference from President Francois Mitterrand, who contends that American economic policy is keeping the dollar excessively high against European currencies and undermining worldwide recovery.

The United States cautioned Syria today that its latest military buildup in Lebanon and along the Syrian-Lebanese border was threatening ''the uneasy peace'' in the area. The public statement followed several days of diplomatic messages back and forth between the United States and both Israel and Syria, officials said. It underscored concern here that the firing on an Israeli plane by a Syrian fighter two days ago might have been the start of a deliberate Syrian action to begin limited fighting with the Israelis. Officials said such a development was highly risky for the Syrians and could set off a wider Israeli-Syrian conflict.

The Soviet Union warned today that the scheduled deployment of new American missiles in Europe would bring inevitable countermeasures, possibly including the stationing of new nuclear weapons in Eastern Europe. A Government statement in Pravda said that the Soviet Union ''finds it necessary to warn with utter clarity: If agreement on the limitation of nuclear arms in Europe, ruling out the deployment there of new American missiles, is frustrated and an additional threat to the security of the U.S.S.R. and its allies is created as a result, the Soviet Union will take timely and effective reply measures in this field as well.'' (A senior Reagan Administration official said in Williamsburg, Va., that most of the warnings and accusations in the Soviet statement had been made before and that its purpose seemed an attempt to divide the NATO allies on the eve of the economic summit meeting of industrialized nations. )

The White House is replacing Thomas O. Enders as the State Department's senior official dealing with Latin America. Langhorne A. Motley, a longtime Republican Party politician who is now Ambassador to Brazil, will be nominated to succeed Mr. Enders as Assistant Secretary of State for Inter-American Affairs. The move was announced this afternoon by Secretary of State George P. Shultz as he flew on Air Force One to the Williamsburg economic meeting. Called Overly Conciliatory Although through the years Mr. Enders had developed a reputation as a hard-liner on some issues, he was criticized by senior White House officials for advocating an overly conciliatory policy toward leftists in El Salvador and was blamed for some of the Administration's problems with Congress.

Konrad Kujau, a Stuttgart dealer in Nazi memorabilia, has confessed to forging the Hitler diaries, a West German prosecutor said today. The prosecutor, Peter Beck, also said that Gerd Heidemann, the reporter who supplied the diaries to Stern magazine, was arrested late Thursday on suspicion of fraud on the basis of information given in Mr. Kujau's confession. In a telephone conversation, Mr. Beck said that prosecutors confronted Mr. Kujau, who also called himself Konrad Fischer, with evidence discovered in his home and offices in Stuttgart and that he confessed in writing on Thursday to having written the 60 volumes of diaries.

DENIS, Reunion - John Boot, a figure created by Evelyn Waugh in his novel ''Scoop,'' once cabled his editors from a far-flung place to announce that nothing much was happening. He then went on to chronicle unrest, upheaval and the outbreak of bubonic plague. In this place, surrounded by ocean and steeped in Frenchness, only the first part of the message would apply: nothing much, at present at least, is happening here. Moreover, the people who live on the island of Reunion - a distant department of the French Republic -seem to want to keep it that way.

By slowing down traffic at its main border post with landlocked Lesotho, South Africa showed today that its arsenal of retaliatory measures against neighboring nations that harbor personnel of the underground African National Congress includes economic as well as military weapons. A spokesman for the South African police said the border post at the end of a narrow railway bridge over the Caledon River that is impoverished Lesotho's main link to the outside world would close four hours early this evening on account of ''manpower problems.'' A diplomat in Maseru, the Lesotho capital, which lies on the other side of the river, said rumors were sweeping the town that South Africa planned to close the border entirely for the weekend. The slowdown appears to have started Thursday afternoon, even before a relatively powerful bomb exploded under a car in Bloemfontein, a South African city that is 80 miles from Maseru. No one was injured in the blast, but it was the first explosion in a downtown urban area since last Friday's car-bomb explosion in Pretoria that killed 18 people and wounded 188.

The Reagan Administration charged today that Cuba was expanding its ''political-military activism'' in Central America and that Cubans, Nicaraguans and guerrillas from El Salvador were jointly planning terrorism in the region. The charges were contained in ''Background Paper: Central America,'' a document made public by the State and Defense Departments. It portrayed Cuba as directing subversion throughout the isthmus, working through both the Sandinist Government of Nicaragua and leftist groups in other countries. The document had little new information. One official called it ''a compendium of background materials'' supporting the Administration contention that turmoil in Central America is caused largely by outside interference. Nearly all the incidents cited took place last year or earlier, and most have been publicized before.

A leftist guerrilla group said today that it was responsible for the killing of a United States military officer here Wednesday, calling it a ''patriotic operation,'' and warned against the ''useless sacrifice of American soldiers.'' Western military officals said that the assassination of Lieut. Comdr. Albert A. Schaufelberger 3d, the deputy commander of the American Military Group here, and other rebel actions in the countryside marked the beginning of a stepped-up offensive by the rebels.

The Sandinist Government extended a state of national emergency today for a year. It said the move was needed to counter covert action by the Central Intelligence Agency. The state of emergency, in effect since July 26, 1982, suspends freedom of expression, travel and the press.