Pride Plumbing came out and provided a cost estimate to perform the following work: 1) access a cleanout outside the home and run a jetter into the cast iron drain line towards the home; and 2) jett the line for about an hour to clear rust from inside it to help waste flow better. Jetting will need to be done monthly for a few months to be able to get the line as clear as possible. After this initial cleaning is done, we recommend a yearly maintenance of the line. We feel this is the best option, for now, to keep from having to cut into the customer's new concrete driveway to replace the drain line.