Mix egg, milk, salt and bread crumbs; allow to soften. Thoroughly combine with ground chuck and chopped vegetables. Shape into loaf and place in Crock-Pot. Top with ketchup and green pepper rings. Place potatoes at the sides of loaf. (If potatoes are peeled, coat with butter to keep from darkening.)
Cover and set to High for 1 hour then turn to Low for 8-9 hours.