Looks like polyethylene tubing clamped to a plastic MIP X hose fitting to me.
I don’t see any copper, only a brass valve screwed onto a galvanized nipple.
It was a very common practice back when galvanized pipes were used for water lines and they did take years to cause a problem.
It would be much better IF both the 45 AND the nipple were brass though.
cduphily
(Chris Duphily, Level II Infrared Thermographer #8355)
22
Brass
cduphily
(Chris Duphily, Level II Infrared Thermographer #8355)
23
It’s well pipe, I guess you could say it’s like pex, only a thicker wall.
Galv. and Brass do not count as dissimilar metals. I don’t know the metalurgy behind it. You can mix brass and/or bronze with iron pipe of anykind and it works.
The nipple clamped in the well line is probably neoprene, used quite often for well fittings. The brass valve looks like the back or down side of a check valve. Other than the wire, I see nothing out of the ordinary.