Water pump comes on every 4 minutes, grass is green near well, hissing sound coming from around check valve

That's a no brainer. The pump kicks on every 4 minutes because you're losing pressure through the check valve and the noise you hear is the water escaping.
This could be as simple as a piece of trash preventing the valve from closing or it could be a fault check valve.
Either way you have to shut the system down, pull the check valve and check. Good luck, Tom