Wash the turkey, inside and out, and dry well. Coat inside and outside with olive oil. Season turkey on the outside with salt and pepper, pressing it in to adhere. Place 2 rosemary sprigs, 1 thyme sprig, 1 sage sprig, 1 oregano sprig and lemon halves inside the cavity of the turkey. Place cooling rack or roasting rack in bottom of large roasting pan. Place turkey on rack, and arrange carrots, celery and remaining herbs on bottom of pan around turkey. Pour 4 cups (1 carton) chicken broth and water over vegetables and herbs.