Turns out its a field office number for the IRS in Fresno, CA.. Specifically the Tax Advocate office for the IRS.  Hope that helps!

Got a call from this number and every time I try and call it back I get this automated message saying to check the number & try again.  Most of the reverse phone number listings says its coming from Avenal, Calif.  when I wiki'ed Avenal, it says its a flyspeck of a town with the exception of a large state prison... So I suspect because of the no call back status, it might be from the prison.