Hello, Mr. Lewis & Mr. Gurley:

I appreciate yall's interest and feedback. After finding the item above, I searched a bit and came up with for sure two mills: Arkadelphia (as Mr. Gurley noted) which blew up 16 Sep 1863, with a huge amount of powder. See link (1) below for a typical write up on it. It was widely reported in papers everywhere, but with very little factual info. Some say 100,000 POUNDS of powder, some say 100,000 KEGS.)

(1) http://chroniclingamerica.loc.gov/lccn/sn83045784/1863-10-01/ed-1/seq-2/#date1=1860&index=8&rows=20&words=Arkansas+mill+powder&searchType=basic&sequence=0&state=&date2=1922&proxtext=Arkansas+%22Powder+Mill%22&y=14&x=19&dateFilterType=yearRange&page=1

The second one has even less info. Not even sure of the location, according to the only item I found on it (Link Below):

http://chroniclingamerica.loc.gov/lccn/sn84026925/1861-05-30/ed-1/seq-1/#date1=1860&index=3&rows=20&words=Arkansas+Mill+Powder&searchType=basic&sequence=0&state=&date2=1922&proxtext=Arkansas+%22Powder+Mill%22&y=14&x=19&dateFilterType=yearRange&page=1

I also found a little material on some later Arkansas powder mills, but no more Civil War era ones. I will post to this thread if I come upon others.