b'4.1 ATR LOOP INSTALLATIONExpanding ATR Loop Testing CapabilityPrincipal Investigator: Nate OldhamTeam Members/Collaborators: Kendell Horman, Vince Tonc, John Naughton, Madison Tippet, Kelly Ellis, Carlos Estrada-Perez, Brian Durtschi, Cody Race, Thomas Berti, R Dale Kepler, and Darrin StefflerThe I-Loop will expandE xpand access and capabilityaccess of the ATR for continued fuel to the Advanced Test Reactorand materials testing. To support (ATR) Medium-I positionthe flowing water loop, the refur-fuel testing capacity,with a flowing water loop, allowingbishment of the 1A cubicle will be address LWR fueltesting of fuels and materials inrequired including new pumps, irradiation testingprototypic Pressurized Waterpiping, heat exchangers, and other capability gaps leftReactor (PWR) and Boiling Waterequipment. Two separate I-Loops by the HBWR closureReactor (BWR) conditions. are planned to support a prototypic and enhance testingPWR and a BWR environment. The capabilities includingProject Description: improvements will enable advanced ramp testing. The closure of the Halden Boilingfuel qualification to continue at the Water Reactor (HBWR) andIdaho National Laboratory (INL) and growing demand for extendingsupport the industry and DOE desire light water reactor (LWR) fuelfor these capabilities in the United performance limits, has createdStates, to support the continued safe urgency to find a testing solutionuse of existing LWR reactors and to support near-term fuel testingprovide for future fuel testing for needs. This need comes at a timenext generation reactors.when industry, via Electric Power Research Institute and the Depart- Accomplishments:ment of Energy (DOE), via theThe I-Loop team has been busy Accident Tolerant Fuels Program,in fiscal year (FY)2023 with the are pushing for performance andengineering design by completing capability increases for new fuels.the conceptual (30%) design The I-Loop project aims to fill theon all tasks and some well into gap created by HBWRs closurepreliminary (60%) design. The and provide a similar capability atobjective is to establish a base ATR, by installing a flowing waterdesign to the point that all major loop in one Medium-I positioncomponents are specified. This and providing access to the otherallowed the project to place the Medium-I positions for futurelong lead procurement ahead of experiments. To provide betterwhen the component is needed. access to the I-positions of ATR viaThe I-Loop project is large in the new reactor top head, a newscope which requires many Transfer Shield PlateMark II hassub-teams working on discrete been designed to allow expanded 194 2023|AFC ACCOMPLISHMENTS'