Place the chicken, onion, 2 whole carrots, celery and water in stock pot. Add peppercorns, herbs, and salt. Simmer for 1 1/2 to 2 hours or until chicken is very tender. Remove chicken and strain stock. Cut chicken meat off bones and refrigerate until ready to use.
Slice the white part of leeks and soak in salted water for 5 minutes to remove grit. Drain well. Place leeks and sliced carrots in large saucepan and add 6 cups of strained chicken stock. Bring to a boil, then cover and simmer for 10 minutes. Add rice and continue simmering for 15 minutes. Add the parsley and some cooked chicken meat to soup. Simmer until heated through. Serve soup hot with whole wheat bread. The remaining chicken meat can be used for another dish. Serves 6