***Naval Information Warfare Center (NIWC) Atlantic requires support for ESS Sustainment.*** ***This opportunity is for SEAPORT NXG MAC HOLDERS ONLY. No other offers will be considered. SeaPort MAC holders will need to register for PIEE accounts in order to receive solicitations and submit proposals/offers in response to the RFP.*** ***The contractors will be tasked to accomplish the work as specified in the Performance Work Statement (PWS). The PWS includes Controlled Unclassified Information (CUI) and will not be made publicly available. In order to obtain access to the PWS, the offeror shall download, complete, and submit a signed Non-Disclosure Agreement (NDA) for each individual requiring access to the non-public documents to Mindy Odenkirk, melinda.k.odenkirk.civ@us.navy.mil.***