How much is "a ton" of it? I highly doubt you got 2000lbs of sand for a 29g tank
. LS is recommended at least 1lb per gallon of water to achieve a 1" sand bed. So in this case a 30lb bag would not be "a ton". Now there are many many of posts out there on the benefits of a deep sand bed, which on average starts off at 4". This would constitute 116lbs of sand or 4 30lbs bags. Again, this doesn't necessarily mean you had too much, it is all about what you want to achieve with your tank.
Now, as far as the sand still being "alive". Given that there is still some liquid left in the bag, and that it wasn't put anywhere extremely hot or cold, chances are the bacterias are still present. Anywhere the sand has become dry though, I am sorry to say, probably means you just have dead sand. I still would take a small cup full from your 29g and use it to seed the new aquarium, just in case.
I am not a biology expert, and I don't know the preservation methods used in packaging live sand, so I can't say for sure that all of the bacteria are alive and well, but I would think that for the most part if the sand is moist, you should be just fine.
