hou30, a knowledgeable mechanical engineer who was responsible for maintaining a potable water supply system told me that the most useful monitoring device on the submersible pump is an ammeter. He got very agitated whenever the motor was drawing more amps than it should. I pass the information on for what it is worth.

my God.. 500 ft. you must not be near the coast. anyway, look at sprinklers at lowes/home depot. they all have diagrams on how far they will "shoot" decide on how many you need and the spacing so they will overlap. you might need more than one circuit depending on how large of an area you want to cover. i have 5 circuits in front and 5 in the back. if your not well versed on gluing pvc, get that way. you'll feed your sprinklers through the pvc (normally 3/4 inch) if you need more than one circuit, you need do design a manifold with multiple shut off valves controlled by a timer.. if you're worried about breaking your pump, dont. i have mine of "quick disconnects". i take it apart in the fall, blow out my sprinkler lines with compressed air, put my well in the shed for the winter so it wont freeze.. thats the only preventive maintenance i do. it lasted me about 10-11 year. a couple of months ago, the electric motor that drives the pump siezed. i bought a new pupm/motor from lowes for 170 bucks.. its currently working like a champ.
reply with any questions about the sprinkler system. easy to install but labor intensive. i did it all myself.

Do you have to use the pvc piping? I am thinking of just laying hoses and connecting them via a 4 way manifold, valves, and a timer. I read in the lawn care section that you can place inground sprinklers (such as Rainbird) on the spikes used for impact sprinklers. Of course I would have to remove all of this in the winter. I really don't want to trench the lawn I already put down. I might try the PVC piping in the rest of my lawn. Any suggestions? I am not really sure how to connect the sprinklers to the spikes.

Jennifer