As part of a long-term dose reduction plan, Ameren Callaway sought to install permanent shielding around one of their regen heat exchangers. The intention was to replace the dozens of lead wool blankets used as temporary shielding, and more importantly, eliminate the time and dose costs associated with installing and uninstalling the temporary shielding package. Working […]
NPO was brought on to provide shielding for Mechanical Penetrations Room No. 1 at Davis-Besse. This room featured a variety of pipe runs with many valves, bends, and reductions throughout as well as many hot spots. Using a combination of drawing information and practical measurements taken on site, NPO provided a shielding package using T-Flex […]
NPO worked closely with AVANTech in designing a set of three shielded casks that reduced dose from 26,000-30,000 mRem/hr (260,000-300,000 μSv/hr) to less than 60 mRem/hr (600 μSv/hr) on contact. Two casks were utilized with one as a spare. Each shielded cask housed one of their Solids Collection Filter canisters for torus water/sludge filtration at […]
For BWR plants, shielding the inner bellows is particularly challenging. During refueling operation the concrete shield plugs above the reactor well are removed and replaced by water. This water filled gap becomes a source for both radiation and contamination. NPO designed a specialized system to address the concerns with shielding this area. Some of the […]
