Preheat oven to 350°. Prepare rice mixes according to package directions. Meanwhile, in a large skillet, cook the sausage, celery and carrots over medium heat until meat is no longer pink; drain. , In a large bowl, combine the sausage mixture, rice, soups, onion powder, garlic powder and pepper. Transfer to two greased 11x7-in. baking dishes., Cover and bake 40-45 minutes or until vegetables are tender. Freeze option: Cover and freeze unbaked casseroles up to 3 months. To use, partially thaw in refrigerator overnight. Remove from refrigerator 30 minutes before baking. Preheat oven to 350°. Bake as directed, increasing time as necessary to heat through and for a thermometer inserted in center to read 165°.,