I have some copper pipes that look like they are corroded pretty badly. I had a plumber over (on another issue) and he said they will spring a leak if left unattended and should be replaced. Pipes are in the crawl space under the house. The first photo is a side view and the second photo a view from beneath. Both pipes are cold water pipes and they are touching each other. Area is bone dry and there are currently no leaks. What do you think? Replace, just ignore or sand the corrosion off and slide some plastic between the pipes? Comments appreciated.