[en] The RV-1 Research Reactor of Instituto Venezolano de Investigaciones Cientificas (IVIC) is a pool type reactor of General Electric design operating from 1961 to 1991, at 3 MW of thermal power. In its life, 76 MTR fuel assemblies composed the total inventory. The enrichment of the fuel assembly was around 19.9 %, and a total of 56 fuel assemblies were eligible for the U.S. Research Reactor Spent Nuclear Fuel (RRSNF) acceptance program. They were returned to the U.S. in two shipments. In 1998, 54 fuel assemblies were shipped in two casks. The shipment of the last two fuel assemblies had to postponed due to concerns about the cask certifications for fuel with identified cladding defects. They were shipped in 1999. Actually, in the facility remain 20 fuel assemblies of U.K. uranium origin, with an average 1% of burn up. They are kept in storage, waiting for a final disposal. In the first shipment two IU-04 casks were used, suitable for shipment of MTR fuel but not certificated to transport fuel assembly with cladding defects. In the second shipment it was used the GE- 2000 to transport the two fuel assemblies with cladding defects. Both shipments were performed together with spent fuel from other research reactors in South America, which complicated formal procedures in Puerto Cabello Port. The tight time schedule also put a lot of stress on the transporters, IVIC authorities, and on the reactor operators. After overcoming some difficulties in the facility, the two shipments were arranged and they arrived safely at the Savannah River Site. (author)