To become a member of Mud Lake Telephone and qualify for Membership, you must reside in one of the following zip codes: 83423, 83425, 83435, 83446, 83450. Each 911 physical address is eligible for one membership. You can complete the membership process by mailing your information to PO Box 235, Dubois, ID 83423, or by visiting us in person at 59 W. Main, Dubois.