Seismic Tests and a Tunnel Freeway?

Caltrans has begun seismic drilling tests in Alhambra to see if a tunnel under South Pasadena, and Pasadena would be a plausible solution to extending the 710 from Alhambra to the 210 in Pasadena. 

 

It's an interesting idea, building a tunnel, to complete the freeway, but I'm not sure I'd really like driving in a 4.5 mile tunnel underneath Pasadena. Not that I'll really have a reason to anyway, but it's just a little scary.  I guess the test will tell us if it's safe or not.