Rich, Thanks for the kind words. Again, just think of anything I say that may be useful as a tax rebate.
I know what you mean, you installed the suckers 'cause you wanted them there. About the barrel... did you punch lots of holes in it to take advantage of the "AREA"? IF there were no holes or just holes in the bottom you may have created a tank to hold water and once filled it might not drain fast enough.
larger dry wells, preferably down hill form the hydrant, even if you have to plumb a drain line from the bottom of the hydrant are a good thing when you have drainage problems. Do not bring the dry well and its gravel too close to the surface. You don't want surface water getting into it and fillling it up too easily.
Also do not discount the deleterious effect of having too much hydrant up in the air. If you expose enough hydrant to the cold air it will chill the lower part of the hydrant and let the valve freeze. Just think the warmer temps below the frost line are in contact with just a little of the hydrant below the frost line and the rest of the length of the hydrant is on the other side of the ledger sheet trying to freeze the hydrant. You want the forces of the warm side to overcome the forces of the evil cold side and prevent the valve from freezing. Toward this end you want to bury deep and expose only a little above ground. Adding insulation, especially above ground will help conserve the little bit of heat available to the hydrant from contact with warmer dirt at the valve level. IT is rare that a "properly" installed hydrant will freeze up, especially if insulated.
Only in the most extreme cases should heater tape ever be needed. Heater tape is a great and wonderful thing but if the power goes down you will have yet more problems if you rely on it.
Oh, about being defective to freeze up.... not so sure about that. If they leak and the riser pipe stays full it could promote freezing but if the valves work OK and don't leak then they freeze when the valve part gets too cold. (see above discussion about evil forces of cold vs the warmth of mother earth) It is rare but possible that the adjustment on the rod controlling the valve is just right so it is good when not really cold but when very cold it contracts and causes a slow leak which overcomes the drain system eventually (even a 50 gal drum) and then freezes as water stands in the pipe above ground level.
Buried deep with not too much above ground or plenty insulation above ground or preferably both and they should not freeze if the valve is adjusted right.
Oh, why a tax rebate? I spent a great deal of my life in school, much of it in evening classes later on. The Viet Nam GI bill paid for some and later my then employer (Fed Gov/DoD) paid for both trips through grad school. So you and the other US taxpayers funded my degrees for which I am grateful. Thanks everyone! Putting a little back is the least I could do.
Pat