THE NUCLEAR TEST GAUGE

Safe and efficient operation of the Savannah River Plant (SRP) production reactors required strict quality control of all fuels and targets that were loaded into the reactors. To analyze the composition of these components in a “nuclear environment,” a large low-power critical facility, the 305 Test Pile, was built. This facility required about 10 minutes per test and also required a relatively large, well-trained crew operating under strict and extensive procedures. The Nuclear Test Gauge (NTG), a small, slightly subcritical facility, was developed to analyze production reactor components about ten times faster than the 305 Test Pile with comparable accuracy and with a much smaller operating staff. After about 20 years of successful experience with the NTG, an extensive modification program was undertaken, which resulted in major improvements. The resulting “mini-NTGs” accelerated component testing with improved safety margins by operating much further below criticality. The mini-NTGs also incorporated improved instrumentation and neutron sources.