Nearly three months after voters rejected a $3.5 million bond to upgrade the track and athletic facility at Belfast Area High School, Regional School Unit 71 is exploring other options for how to fund the project. Paying for all or part of the project directly through the school budget or launching a capital campaign to raise funds are among possibilities being considered, school officials said. Doing nothing is not an option, said Susan Robbins, the school’s athletic director. And the bleachers and lights at the high school were installed in the 1960s and need upgrades. The district will also have to convince the public that upgrading athletics facilities is a worthwhile use of funds.