When you have a plumbing issue that needs professional attention, look no further than Handy. No matter how skilled you might be at home maintenance, some jobs should only ever be tackled by a professional, and plumbing is one of them. When you book local plumbers through the Handy platform, you'll be booking a cheap but reliable plumbing professional who will know just where to look to find the source of the problem and who will have all the right tools and expertise to fix it. You'll never go looking for a "local plumbers near me" again!
Wall thickness does not affect pipe or tubing size. 1/2" L copper has the same outer diameter as 1/2" K or M copper. The same applies to pipe schedules. As a result, a slight increase in pressure losses is realized due to a decrease in flowpath as wall thickness is increased. In other words, 1 foot of 1/2" L copper has slightly less volume than 1 foot of 1/2 M copper.
If nothing inside the home was altered you should not be getting a smell. Personally I'm confused as to why the repair person would have left the original line there and ran another one through a new hole. I would have pulled the old line up, ran the new line (in PVC) and used the same hole in the septic tank instead of creating a new one. Did he seal up the hole in the tank from the old line?
A leaky faucet can be a relatively easy fix depending on the type of faucet, so get to know the basic types of faucets and how to take them apart. You can look for instructions online; YouTube videos are the most useful. A slow drip usually means that all you have to replace is a washer, but make sure you know which size you need before buying a new one.