1966 Plymouth Valiant Wheels/Tires

Awesome thank y'all for the help! After talking to my brother (who, lucky for me, helped move the car to the shop where it is now) informed me that they replaced the rotted out tire with a spare he had from his Dart and that all the tires need is some air and that they'll suffice for now. So I won't have to tackle that issue yet. My next question, however, is regarding media blasting. I got in touch with an auto restoration business who have been nothing but awesome to me so far. I asked what type of material they use and they said silica sand. Now correct me if I'm wrong, but hasn't there been quite a bit of debate on what type of material should be used to clean up a car? Any suggestions?