Need a sanity check prior to digging the trench this coming weekend. I need to connect our 4" discharge line that is currently going to our septic tank to a newly installed grinder station that is part of the sewers recently installed.
The existing 4" line is approximately 24" below grade; the distance I need to run to the grinder station is 10'; and the inlet stub out to the grinder station is 60" below grade.
My plan is to use a 90 degree large radius sweep fitting (is this necessary or can I use a standard 90?) to connect to the existing line to begin my 10' line toward the grinder station; after 10' of line run at a 2% slope use a 45 degree fitting to align with the grinder station inlet stub; then a standard 90 degree fitting to vertically drop the 33" to another 90 degree fitting that transitions back to horizontal and enables me to couple with the 5' inlet stub out provided by the sewer entity.
The existing sewer line leaving the basement has a clean out located inside the basement (the reconfigured line length will be 40' in total). So I believe I should not require another clean out since my horizontal pipe changes will not exceed 135 degrees. Is this correct?
The pipe bed will simply be the compacted soil of the trench. Is this code acceptable?
Have I missed something?
Thanks for your help!