Outside Water Line to Yard Hydrant

[Jimmah!]

I am interested in installing a FF water hydrant in my yard here in 60302/Illinois (located just outside and immediately adjacent to the city of Chicago in the Village of Oak Park). The line would exit the home, run horizontally exposed beneath a porch for about 8 feet, turn down and drop about 4 feet to the ground, and then continue u/g to the hydrant. What type of pipe am I allowed to run for both conditions? If multiple materials are allowed, what is your opinion?

Also, what is the minimum burial depth for the new supply line? Below frost line?

I do plan on installing a stop valve and tap to connect an air compressor so I can blow the line out before winter as well as a backflow preventer between house and hydrant supply line.

Thanks in advance!
J