Access SP Term Store from console app

I have a console app that i used to connect to SP online to get termstore data:

               ClientContext context = new ClientContext("https://site.sharepoint.com/";

                SecureString passWord = new SecureString();
                foreach (char c in "xxxxxx".ToCharArray()) passWord.AppendChar(c);
                context.Credentials = new SharePointOnlineCredentials("username", passWord);
                TaxonomySession taxonomySession = TaxonomySession.GetTaxonomySession(context);
                context.Load(taxonomySession, ts => ts.TermStores);
                context.ExecuteQuery();

That works great and I can connect to the term store and get data no problem... now we have decided to move on prem.  I still need to connect to the term store from a console app that will run outside of the SP environment. 

I have added a user to the term store in both Central Admin and site settings.. .has full control.. 

I cannot figure out how to pass auth to SP to give me access.. .I just keep getting 401.

Any help would be appreciated.  

sayitfast