us guys-
when we put that shit together, use all manner of chemicals. if the plumbing in your house is PEX, lucky you, you've made a good choice for the future.
copper on the other hand, lays around on the job, gets full of sawdust, dirt, concrete dust, bugs, etc. then ol leaky comes along with his torch and smears ACID all over it to sweat the joint.lol, sweat the joint.
anyway, the underground is even worse. the water comes to your street via a large iron(ductile) pipe, that really gets exposed. they lay around all types of places, such as industrial type areas where they are warehoused, and on the job site. so it's oil, fuel, pvc glues and cleaners, grease, dirt, leaves, bugs, animals, feces, concrete dust(from the sanitary and drain work), etc.
this iron pipe has a self tapping valve they install at every lot, to install a smaller copper lead that supplies each individual residence.
when they get the main all installed(valved, and backfilled), they test it. for pressure variance, and contaminants. bet you can't guess what they use to clean the line? that's right, chlorine. massive amounts of chlorine. they main is valved so if a repair is to be done it can be isolated. think bucketfuls of chlorine per section. add until the system tests clean for biological contaminants.
then, how do they flush all that? good question. they open it up. until chlorine levels at the release source test within acceptable limits. through personal experience i would say they're not gettin it all. i can usually taste solder flux in a new house for two or three years.
imagine if the jerk down the sewer hole, installing the isolation valves in the main(that's what's down some of those holes, valves half as big as a VW bug), gets pissed at his boss and throws his half eaten lunch, and the resulting pile of shit down the line?lol
never done that.
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