LOFT Monthly Progress Report for February 1980

The significant event of February was the on-schedule conduct of Test L3-2 on February 7. This was the second LOFT small break test with nuclear heat. It simulated a break of a one-inch pipe in a large commercial plant, whereas Test L3-1 had simulated a break of a four-inch pipe. For Test L3-2, the reactor plant and emergency core cooling system appeared to function as expected, although preliminary data evaluation indicates a higher break flow than expected, with a correspondingly greater depressurization. As the month ended, data evaluation was continuing. During February, Nuclear Regulatory Commission guidance was received that would require Tests L3-5 and L3-6 to use nuclear heat. Previously these tests, the next planned tests, had been designed as nonnuclear tests with and without operating coolant pumps. This revised guidance will require a replanning of the entire program schedule for better facility use. At the end of the month, replanning was underway. Costs for February are right on budget, although manpower levels are somewhat greater than budget. This latter variance results from an intentional manpower-material interchange