What the dear NSA allegedly mean by "Mystic site"?

[Georgi Guninski]

>From cryptome:
http://cryptome.org/2013/11/snowden-tally.htm

19 May 2014 	12 Various Pages 	12
http://cryptome.org/2014/05/nsa-intercept-14-0519.pdf

p. 2 of the pdf:

"Approx 10-15 SIGINT reports pers week from "Mystic sites"
other than Sca....."

1. What does "Mystic site" mean to the dear NSA?

2. Is "site" in the usual computer sense?