For the Salad:
Heat the olive oil over medium-high heat in a saute pan and brown sausage. Remove to a cutting board and slice into 1/4-inch pieces, then return to pan and cook over medium heat until cooked through. Using a slotted spoon, remove to paper towels to drain.
Combine sausage, green beans, 2 tablespoons of the chives, and scallions in a large bowl. Add enough dressing to coat. Then gently fold in potatoes, taste and add enough dressing as needed. Do not feel compelled to use all of the dressing. Serve family style, garnished with remaining chives, and with any extra dressing on the side.