Hi trebdms,
My understanding of the interrupt command is it places a line of code checking the interrupt pin between every line in your program. So your bit of code would actually look like so:

low LED1 ' ON LED
'check interrupt
pause 30000 ' Hold ON for 30 secs
'check interrupt
high LED1 ' OFF LED

When I need pauses in a program using an interrupt I usually use a For....Next loop.

low LED1 ' ON LED
For y = 0 to 30000
pause 1
next y
high LED1 ' OFF LED

This way the interrupt pin gets checked every millisecond.