Decontaminating (and possibly sanitizing) dirty copper plumbing before putting into service

[Rossn]

TLDR: I have some 1" copper that sat partially installed a long time, and is a bit gunky inside. Do I need to cut out the ends and physically remove the construction dust/gunk and then sanitize it? Or, is there a good flushing means to clean the walls of the pipe through flushing?

Background:
I recently picked up a part of my project that has been idle, which includes a 1" copper water supply trunk running about 70' out to the garage and apartment above it. The first 20' (through joists) was run maybe 5 years ago, with the supply end getting a ball valve maybe 3 years ago. The rest was run in recent weeks. I found the loose sticks of copper I had pretty gunky ran a damp, packed blue paper towel through them prior to install. They took a couple passes to get the towels coming out looking clean, and not darkened. What would you do with the first 20' that has been sitting?

 

[Storm rider]

I would use a fish tape to run an alcohol soaked cloth through the pipe. You can also sanitize with bleach.

 

[Sponsor]

 

[Rossn]

I would use a fish tape to run an alcohol soaked cloth through the pipe. You can also sanitize with bleach.

Thanks, Storm rider. with 2 offset sections, I couldn't run a fish tape, but was able to feed a wire down it, pull through some electrician's pulling twine and pull a rag through 4 times. All clean now.