Arizona's No. 1 news story for 1981, as voted by the staff of The Phoenix Gazette, was a happy, precedentsetting event that also ranks among the top nationwide. . The news was the appointment of San4ra Day O'Connor of Arizona - a judge, politician, lawyer, wife, mother r. the first woman to sit as a justice Qt the United States Supreme Court. P-.esident Reagan announced her ppdintment July 7, and from then fnti\ after Justice O'Connor began t sking questions from the bench of _he nation's highest court, the Arizoilan continued to be front page news. ' Justice O'Connor was serving on fhe Arizona Court of Appeals at the time of her nomination. She prefiously was a Maricopa County Superior Court judge. : The remaining nine 1981 stories on 'fheGazette list, are the: ' • Shelving of the proposed Orme barn at the confluence of the Salt and \Terde rivers in favor of a Waddell Dam on the Agua Fria. • Beginning of the Arizona Lottery, Its unprecedented success - and its J>ro~lems. 1 • Death of Bishop James Rausch of the Catholic Diocese of Phoenix and the appointment of Bishop Tom O'Brien as his successor. • . • Passage of a $5.8-billion transportation package - including an 8 percent gas tax based on the average retail price per gallon - and the initiative effort that will give voters a chance to turn down that increase. • Redistricting of the five congressional and 30 legislative districts to l;onform with one-man, one-vote manpates based on the 1980 census. : • Natural gas explosions,