The Large Trenching machine was quite useful in digging out for the Fresh air inlet to the underground dome complex, but it still took some shovel work to get the trench the needed 30 inches wide and deep. The rare July rainstorm didn't help in the trench clearing process.

 
I got some good exercise here, as you can see.

I learned how to get the bobcat un-stuck.
The Silverado wouldn't pull it out this time... Above, you can see where I have installed the first of the 15 inch underground air distribution tubes, this one leading to the master bedroom.