We are going through similar problems with, of all things, our field-lines too.
The drains & fresh water pipes were to thin and burried to shallow when installed.
The field lines have since collapsed, and are now leaching UP through the soil instead of DOWN.
Most days you can't tell there is a problem, but let laundry day roll around, and
a small stinky spring emerges from the ground.
We were able to replace out fresh water lines last year, which after 8 years of rain-water errosion, had been laying ABOVE ground, and froze every year.
Sorry you had to go through all of that! I hate it when people do shoddy work. They know it only has to last until it gets out of their hands, then it's some one else's problem & some one else's dime.
I like to do things so well, that aside from normal wear, what I've done LASTS.
At least know, you will know that it was a job well done.