PHILADELPHIA — The school was tucked away in the mountains of Northeastern Vermont, far enough from everything that Richie Graham said the only things around were a gas station and a general store. Burke Mountain Academy — which Graham graduated from in 1987 — might not have had much outside its gates but it did have a clear mission: produce world-class ski racers while providing a high-school education. “The middle of nowhere,” Graham said. “The school is like a farmhouse. It’s not a fancy kind of place. But it’s kind of the Juilliard of ski racing.” It opened in 1970 as the country’s first s…