Performed hydrojetting to mainline via cleanout under kitchen sink. Followed with camera inspection and found that customer had large amounts of mud in sewer line leading out towards septic tank. Was unable to run my camera to septic due to the amount of build up. Recommend digging up sewer main outside of building and performing more hydrojetting in attempt to remove all the mud out of sewer line and installing a mainline cleanout outside to provide future access. Once mud is removed from sewer line we can then follow up with camera inspection to make sure there are no further issues Installed mainline clesnout and performed jetting. Was able to clear clog. Followed with camera inspection and found a section that was backgraded right before the sewer line tied into the septic system. I believe this section of backgraded pipe is what lead to the build up. Flushed out system and everything was draining properly