The following is being reposted from the EPA CHIEF Listserv:

Version 5 of the ERT is now available. Updates have been made to the ERT application, User’s Manual, Example Project Data Sets, and Instructional Videos to reflect the Version 5 improvements. These updates are available on the ERT Version 5 web page at http://www.epa.gov/ttn/chief/ert/index.html .  For information on the revisions to the ERT please see the update history at http://www.epa.gov/ttn/chief/ert/updatehistory.pdf.

BTS has been informed that Project Data Sets created in Version 4 will be functional in ERTv5.