No, there are not sufficient procedures in place to guard against physical tampering with electronic voting machines, because voting is still handled locally. Most people do not get involved with overseeing elections unless they have an interest in the outcome. It is very easy to tamper with the machines, and there are few election inspectors to make sure the locals do not cheat.
I do not believe that there are enough procedures in place to guard against tampering. Technology is improving and changing everyday. People are getting smarter. Electronic voting machines have to keep evolving and updating. Procedures have to be tested. There is always a way. Went I went to vote in the Presidential Election, I was not voting for Obama, but yet every time I hit the other candidates name it would select Obama. I stepped out and got a poll worker who said that you have to touch it on the very side of the screen to vote for him. I was so in shock.