To find out how much sand the truck has when it arrives at the yard, we need to subtract the amount of sand lost from the initial amount of sand it was carrying.
Initial amount of sand: 335.526 pounds
Amount of sand lost: 9.081 pounds
Now, we can perform the subtraction:
\[ 335.526 - 9.081 = 326.445 \]
Therefore, the truck has 326.445 pounds of sand when it arrives at the yard.