[Dart] Duplicate error messages

[Ted Berg]

I have a Dart2 server which is sending duplicate build error emails.

Both registered individuals and the DefaultContactList receive duplicate 
error emails.  The pattern appears to be 4 emails sent when a build 
fails, all of which reference the same build error.  This behavior holds 
whether it is 1 error or 80 for any given build.

Is this a configuration problem, and if so where would I find the 
offending option?

Ted