i need to see this sled. when i started installing septic systems in the early 90's, the backhoe dug the ditch ten carried the rock and dumped it in the ditch, the labor ME! would tell him how much, then while he went to get more rock i would get in the ditch and shovel the rock to each side of the ditch and make a v in the gravel. this would go for a 20-30 feet then i would start going back and clipping 10' sections of pipe together and raking the gravel back over the pipe. cover with straw or paper then off to the next on. now this was a lot of work and i always slept well. 330' is the average 3 bedroom system here. this would take a good hard long day to install. 8-10 hours
now when we do gravel we take a skid with us. as dad digs i carry with the skid. when i dump the gravel in the ditch, i take the bucket and rake the gravel to each side with the bucket. THIS IS THE BEST IDEA I EVER HAD!!!! then i take a shovel or sometimes just my foot and level any little spots that need it as i lay the pipe. then get another bucket of gravel and sprinkle a little gravel to cover the pipe. then straw or paper over that. we can put these in about 5-7 hours.
now we do a lot of chambers how they go in has been discussed, it takes us about 3-4 hours to install one of these systems. we get a 30% reduction for useing them here. i think they work alright, but would rather install gravel as i get a full days work out of them and i am just labor on these jobs. they do save quite a bit for us. my pay is around half, material is the same, and no wear and tear on a tracked skid.
we did put in the gravel-less pipe for a while but the inspecters really hate them now, and i hated dragging those 20' sections of 10'' pipe up and down hills.
when it came to installing one at my house i went rock all the way......i think they are the best, guess i am a little old school.