<p>Going back to the OP, "what kind of questions CAN you ask?", perhaps the alum is uniquely able to describe:
How has his degree held up within his profession; how is it regarded by the communities he's lived and worked in since college </p>
<pre><code> why s/he chooses to devote volunteer time this way when so many other uses are competing for the time (that's a softball question but will result in your hearing
</code></pre>
<p>the best things about the school)</p>
<p>How has the college changed over time (assume they read everything about the college in writing, at the very least); what hasn't changed (enduring values of the school) </p>
<p>Keep in mind that this person might also play a role in whether or not you are accepted to the college. </p>
<p>I note that my alma mater has, in some ways, a new culture around every l0 years, so unless someone is that close to it age-wise, I don't know that an alum who's been away 15 years is that much better than one who's been away 25 or 35 years. Besides, anything the alum can't answer due to age could be gleaned better by staying overnight with students on-campus.</p>