To submit XML data to Production ICIS, use the ICIS-NPDES Dataflow on the NGNProd2.0 Node. This can be found on the Production Exchange Network Services Center: https://enservices.epa.gov .
To submit XMLs to ICIS Test, use the ICIS-AIR Dataflow ('ICIS-AIR' is all caps; avoid the other 'ICIS-Air' dataflow. These names will be updated sometime in the future.) on the NGNTest2.0 Node. This can be found on the Test Exchange Network Services Center: https://enservicestest.epacdxnode.net .
To submit XMLs to ICIS Stage, use the ICIS-NPDES Dataflow on the NGNTest2.0 Node. This can be found on the Test Exchange Network Services Center: https://enservicestest.epacdxnode.net .
(Dataflow and node names should change to more intuitive values in the future.)
Node endpoint URLs: http://www.exchangenetwork.net/epa-node-endpoints/
XML Validator to check for any mistakes before submitting: https://tools.epacdxnode.net/soapclient.html
Retrieving ICIS data with the ICIS Data Access (ICISDA) Dataflow: https://icis.zendesk.com/hc/en-us/articles/207374636-DOWNLOAD-XMLS-FROM-ICISDA-DATAFLOW-TO-CORRECT-ICIS-DATA-
Steve Rubin's Excel spreadsheet tool for mapping Excel data into the ICIS XML format: https://icis.zendesk.com/hc/en-us/articles/209718183
More information about ICIS data flows can be found at http://www.exchangenetwork.net/data-exchange/icis-npdes/ and http://www.exchangenetwork.net/data-exchange/icis-air/ .
ICIS-NPDES and ICIS-Air EDT/Batch technical specification documents are here: https://icis.zendesk.com/hc/en-us/categories/201119856 .