Disregarding the mass/energy issue.
My first thought was something like a giant vacuum cleaner.
In particular, we'll say that one mouth is floating somewhere in free space, and the other falls into Earth's gravity well. The radius of the mouths is 1 meter.
Where the atmosphere blasts out of the end of the worm hole into space. But after thinking about this for some time. I realize that earths gravity may well transverse the wormhole too. So you may get some atmosphere shooting into space, but it could form a spherical ball around the wormhole (Assuming the wormhole is spherical in effect). Held there by earths gravity, at some point these two forces would probably equalize.
If the wormhole hit the ground, I doubt anything special would happen. I don't think much dirt and rock would get sucked out into the void just by the shear vacuum of space. Again, because earth has enaugh gravity to hold this stuff normally and just a 1 meter area of vacuum probably wont overcome that.
So if you allow the vacuum of space to transverse the wormhole, you almost have to allow gravity and anything else to transfer too.
Of course you could have a one way wormhole, I suppose.