You may have a worn gasket. I wouldn't use epoxy. With all the heat, it wouldnt stand up to it anyway. I would just do it the right way and take the water pump off and replace the gasket. While you got it all off, may as well change the water pump too.
First off: These cars don't have gaskets on the waterpumps. It has an O-Ring that seals the pump up, and it typically doesn't just go bad.
More than likely, it's actually leaking from the weep hole on the bottom of the water pump. That hole will allow it to leak to let you know that the bushings in the water pump are worn out, and it needs to be replaced completely.
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