Amid disagreements over the effects of both measures, the Virginia House of Delegates approved legislation today that would prohibit oil refiners from expanding their service station ownerships and killed another controversial proposal restricting the sale of beer to 18-year-olds.

Although the nation's top antitrust official had warned in hearings last week that the service station proposal would likely increase gasoline prices for consumers, the House voted 67-25 for the bill and rejected attempts to exempt independent refineries from its provisions.

"We don't seek to penalize anybody," argued Del. Richard L. Saslaw (D-Fairfax), the measure's chief sponsor. "We just want to keep the market competitive."

Lobbyists for the service station dealers sat in the gallery and hovered outside the House chamber during debate on the bill, which they said is needed to protect station operators from unfair competition from the oil companies that supply them with gasoline.

The legislation, if passed by the Senate and signed by the governor, would prevent oil producers and refiners from opening any new stations in the state after March 1 of this year unless they are operated by independent dealers.

Del. Gary R. Myers (R-Alexandria) supported the bill for its importance to the small dealer but said the measures "does little for the efficiency of the marketplace and little for the consumer."

Del. Raymond Guest Jr. (R-Warren) opposed the bill, saying he was not convinced it "will increase competition." He also said he feared that the provision "that says the producer cannot also retail his product... could be extended to apply someday to apple growers or beef farmers."

The gasoline bill was supported by all Northern Virginia area legislators with the exception of Del. Robert Thoburn (R-Fairfax). Del. Robert Harris (R-Fairfax) was absent during today's House session and did not vote.

In its longest session to date as the Assembly pace picks up, the House took action on a number of proposals that have provoked much debate by members.

Chief among them was the drinking age measure that would have prohibited 18-year-olds from buying beer unless they planned to drink it at a supervised place of purchase.

The House voted 52-to-44 against the bill, whose sponsor, Del. Warren E. Barry (R-Fairfax), had sought the measure as a means of controlling teen-age alcohol abuse, particularly while driving or on school grounds.

Del. Martin Perper (R-Fairfax) successfully challanged the proposal and cited statistics showing there are some 7.000 "19-year-olds and some 20 and 21-year-olds still in state schools." He also warned that Barry's bill would "force 18-year-olds to drink beer in a bar or tavern and then assure they are going to drive home drunk."

Perper, saying that curbs on teenage drinking "should be done whole hog or not at all," also argued that Barry's bill would have little effect in Northern and Southwest Virginia where 18-year-olds can buy alcohol in the District. Maryland or Tennessee.

In other House action, delegates voted 76 to 22 to approve legislation that would exempt church-operated daycare centers from most state health and safety regulations. Eleven such centers have surrendered their licenses and intend to sue the state alleging invasion of their ministries unless the Assembly resolves the dispute.

Opponents of the measure argued without success that the bill, in the words of Del. Lewis Fickett Jr. (D-Fredericksburg), "will result in a lessening of licensing inspection and care for those little kids" who attend church-run centers.

Also in the House, an expected move to override a gubernatorial veto was set in motion today when delegates voted 77 to 20 to approve a bill that would allow political candidates to be identified by party on general election ballots.

Gov. John N. Dalton, a Republican, vetoed similar legislation last year, but Assembly Democrats hope to give the same bill to him again more than seven days before the end of the session. This would allow them time to override a second Dalton veto.

The Senate passed two measures today relating to investigation and removal of state judges. By a 28-to-9 vote, it proposed a constitutional amendment that would eliminate the mandatory denial of retirement benefits to judges removed for misconduct.

The proposal grows out of the denial of retirement benefits to former Richmond District Court Judge Harold C. Maurice after his removal by the Supreme Court. A movement in the Senate last year to restore Maurice's pension was aborted when it was discovered that the State Constitution prohibits the Assembly from reversing a Supreme Court action of that kind.

Sen. William F. Parkerson Jr. (D-Henrico) argued that the current constitutional penalty is too harsh for some cases and that the Assembly should provide a range of penalties by statute to punish judicial misconduct.

Sen. Clive L. DuVal II (D-Fairfax) strongly opposed the proposed amendment. He said judges should be held to the "highest standards of conduct" and should be denied pensions for violations that warrant their removal.

The amendment now goes to the House. It must be approved by the full Assembly this year and again next year and then by voters in referendum before becoming effective.

The Senate also approved House-passed changes in a law requiring secrecy in investigations by the Judicial Inquiry and Review Commission, the agency that investigates allegations of judicial misconduct. The U.S. Supreme Court overturned a portion of the current law when the state tried to prosecute the Norfolk Virginian-Pilot for writing about the investigation of a state court judge by the commission.

The changes in the law approved by the senate, 38 to 0, are intended to comply with the Supreme Court ruling by applying the secrecy requirement only to those with official knowledge of commission proceedings.

However, Parkerson tacked on an amendment just before the floor vote that would also apply the secrecy rule to witnesses before the commission and to anyone questioned by the commission staff about a complaint against a judge.

The amendment passed without debate.