Blue smoke if van sits for one hour then restart

I have a 93 Astro Van with 75,000 miles. I can drive vehicle for 3,000 miles with 1/4 court of oil consumed. If I drive and shut down and restart there is no blue smoke. If I drive and shut down for one or two hours, I have large amount of blue smoke. What is causing this problem? What action can I take to eliminate this issue; it bothers me!

Thanks
gregg:runaround:

Sounds like valve stem seals.