I think you must have meant Calhoun County, not Callahan. Frequency 156.2175 is not licensed in Callahan County, but is listed for Port Lavaca in Calhoun.
The database does not show it to be encrypted, but it may have changed. Looking at the update history for that county, since 2012, the only updates involving Calhoun County have been to ham radio frequencies, and a large number to the electric utility, American Electric Power / Central Power and Light System. I have not been in that part of the state for a very long time, so no personal knowledge as to what frequencies are used, and whether or not encryption may have been added.
I'd suggest that you use the Report link in the lower left corner of your post, and ask that a moderator corect the county name, so that someone in that area would recognize it.