All Potentially Dangerous Dogs or Dangerous Dogs shall be securely confined indoors or in an enclosed and locked pen or structure upon the premises of the owner. The pen or structure must have minimum dimensions of five feet by ten feet (5' x 10') for dogs less than 40 pounds or eight feet by ten feet (8' x 10') for dogs 40 pounds and over, and must have secure sides, and a minimum height of six feet (6'). If no bottom is secured to the sides, the sides must be embedded into the ground not less than two feet (2'). All pens and structures must be kept clean and sanitary. The enclosure must also protect the dog from the elements.