I have a large, mature silver maple that's planted about 2 feet away
from my driveway. I am currently getting estimates for getting my
driveway (40 years old) re-paved. In the scope of work, the
contractors say that they will excavate 12" of the old driveway, put in
a 10" gravel bed, and 2" of asphalt. I am concerned as to how much
root damage my silver maple can sustain.

Below is a very crude "overhead" picture of the current driveway and
tree. The trunk of the tree is represented by the letter "O". As you
can imagine, any roots of the tree 12" deep from roughly 1 o'clock to 5
o'clock will get severed. Is that too much damage? It is a large
silver maple. The diameter of the tree's trunk is probably at least 3
feet, and its crown could easily be 45 feet wide.

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