Gov. Arnold Schwarzenegger will nominate Tani Cantil-Sakauye, a Republican appellate court justice with a reputation as a moderate, to be chief justice of the California Supreme Court, The Bee learned Tuesday. Cantil-Sakauye, 50, of Sacramento is a former prosecutor and Sacramento Superior Court judge. She would replace Chief Justice Ronald George, who has announced he will retire Jan. 2. Cantil-Sakauye has been on the 3rd District Court of Appeal since 2005. If approved by a three-member commission and by voters in November, she would start a 12-year term in January. She would be the state's first Filipina American chief justice.