You will likely see more of this, as this is not the correct method for installing hydrants. And unless you live someplace that doesn't get any frost, these will not be frost free. At least half of that shaft needs to be under ground, with the base surrounded in gravel or rock. When you close handle, all the remaining water in the stand pipe drains out of that brass fixture at the bottom. It needs to be surrounded in rock and gravel so it has some place to drain to.
You are placing a ton of stress on that PVC Tee.
We would rarely place a hydrant directly on a main water line, especially PVC. If something bumps into this hydrant, you get an instant pipe break and a large muddy mess.
I know you already have this installed, but I would replace that PVC with 1" or 1 -1/4" black poly pipe rated for 125 lbs pressure. Wherever you need a hydrant, install an insert t, use stainless screw clamps, and then about a 2 foot piece of that same pipe coming off that T. At the open end, place a BRASS or STEEL hydrant adapter elbow (insert x female Iron pipe threads). This allows enough flex in the system, that operating the handle, or a bump against the hydrant will not damage the underground piping. If you have any animals, you will be amazed at what they do to yard hydrants trying to get the "magic post" to make more water. The only thing that damages more hydrants than livestock, is MOWERS.
PS, don't bury that valve. Take it out completely or it belongs inside that building.
PPS, don't use gate valves if at all possible. Use ball valves for better flow and resistance to leaks.
