In the interest of keeping the thread unbroken I’m replying to your comment here
You can cut the pipe midway to the ground and install a twist union, so that in the future the repairs are easier:
You will likely need to make two cuts per valve, so that at the end you can completely remove the valve and fix the leak.
Unscrew the cut peace from the valve and reinstall it using the sealant, it is easier to apply generously and not worry about breaking the union: