Hi all
The water pump seal is a normal mechanical seal. It has one fixed and one rotating face with the parts loaded to the correct pressure with a spring. The face of the seal is lubricated by the coolant. When an engine sits for a period of time it is often going to have to allow some coolant to enter the sea face again for lubrication. There will be some drip occur in that case from the weepage bore holes directly behind the water pump distribution cover on the ignition housing. Once running it should stop but you will get some drip directly below the engine at the ignition side.
As long as there is no weepage after warm up then don't worry about it. On inspections, like the 100 hour or annual, check it when you do your warm up run for oil change or compression testing. A coolant stain on the floor or bottom of the engine cowl is not an issue as long as it is stable.
Cheers