I got that information from a long time employee of Walmart.
The Colorado State laws pertaining to drug use on the job are not compatable with the new marijuana legalization.
Steamboat Springs — Two men suspected of growing nearly 1,000 marijuana plants in the Routt National Forest remained in federal custody Friday.
http://t.steamboattoday.com/news/2015/sep/04/suspected-forest-marijuana-growers-remain-custody/