This is a request for an Expression of Interest to fabricate a complete Ion Exchange Column Assembly for the Advanced Test Reactor at Idaho National Laboratory. The work involves fabricating a complex assembly with strict nuclear-grade standards, including stainless steel columns, lead shielding, and seismic design, for delivery to a logistics facility in Idaho Falls, Idaho. The vendor must demonstrate extensive experience with nuclear fabrication, compliance with codes like ASME Section VIII and AISC N690, and a quality program equivalent to ASME NQA-1. The fabricated system must meet specific design conditions, including a pressure rating of 2500 psig and radiation shielding requirements. This EOI is the first step to identify qualified vendors for a potential future Request for Proposal.