Quinoa salad with chicken and grapes

1 c. quinoa
2  c. water
3 1/4 tsp. salt, divided
2 tsp dijon mustard
2 T lime juice
1/2 tsp. cumin
1/2 tsp. pepper
6 T Olive oil
2 c. cooked, diced chicken
1 c. halved grapes
2 celery ribs, finely chopped
Rinse quinoa and put in boiling water and 1/4 tsp. salt.  Return to boil and simmer 15 min.  whisk sauce ingredients together and combine all ingredients.  Serve hot or cold