Another septic tank riser issue

It must me something in the air. At least it is when you pop the lid -LOL! Anyway, I asked that the backhoe operator allow for a cleanout for the septic tank (long story - not new construction) so he left two, 6" PVC pipes with covers on them. Something posessed me to look inside them after three years and the 6" pipe is apparently a shield around a 4" line that goes to the tank. You can look right in on the discharge end and all I can see is more PVC at the bottom of the intake side. Funny thing is that I only see a little bit of water trickling through on the intake side when I flush - no solid or paper. Well, it's coming 'round to mandatory clean out time and there's no way that those pipes are going to allow for a pumping truck's hose to do a good job. I need to put in some risers and a lid, down the 23" to the tank. Which end? Or do I do both ends of the tank? TIA, Chuck
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.