I would be concerned with the box flooding..
I would bring the power out as UF, and either put a PVC j-box with a marine receptacle with a watertight cover, or transition to a ST pigtail, with a watertight boot that can be pulled out of the box. don't forget a notch in the lid of the cristy box to allow the box to be closed when in use, and some form of handle to allow it to be opened. maybe a split cover?
I would feed it from a GFI and a weatherproof switch located on the fence/dugout. add a second GFI outlet at that location.
put these in a locked box to prevent vandalism.
check the hubbell/bryant marine products catalog.
[This message has been edited by techie (edited 05-01-2006).]
