Alan, the ACS was a “desk job,” i.e. a support role, but with no actual involvement in combat. Note the following:

“It shall be the duty of assistant commissaries of subsistence, or storekeepers, to receive and account in the manner hereafter prescribed, for all subsistence stores entrusted to their charge; and to make and transmit to the proper accounting officer, through the office of the commissary general of subsistence, all returns and accounts. They will not receive subsistence stores from contractors, until duly inspected, according to the terms of the contract.”

This is from a Federal source, which is online at:

http://books.google.com/books?id=Y5YbAQAAMAAJ&pg=PA254&lpg=PA254&dq=Assistant+Commissary+of+Subsistence&source=bl&ots=A72GFCmroJ&sig=5Jid2VBRy3KLKhcwlOUjWxzkEzI&hl=en&ei=GKWVTv7fAZTIsQK1rKTvAQ&sa=X&oi=book_result&ct=result&resnum=4&sqi=2&ved=0CDAQ6AEwAw#v=onepage&q=Assistant%20Commissary%20of%20Subsistence&f=false