AIKEN, S.C. - Employees at the Savannah River Site developed a safe, efficient fix to a tricky problem that long impacted sampling tanks storing plutonium solutions.
The employees make plutonium oxide, a non-weapons, usable form of plutonium, at HB Line, the site’s chemical processing facility. The plutonium solution is an intermediate form of plutonium oxide powder.
Regular sampling is required to monitor the solution to ensure appropriate processing conditions. The tanks have built-in sample boxes with needles and vials to withdraw samples of the contaminated solution.
The solution sometimes clogged the needles in the vials. Operators threaded the capillary and needle with the equivalent of thin piano wire, using force to clear it. They employed rigorous safeguards to avoid contamination and contact with the sharp wire and needle.
“A team of HB Line employees, including maintenance and engineering personnel, began looking at ways to improve our sampling process and reduce hazards associated with that activity," HB Line Deputy Facility Manager Nick Miller said. “They came up with a different approach, which has turned out to be a safer and equally effective method of clearing the capillary."
The new method involves placing a filtered nipple with a vial attached over the end of the sample needle. Operators use a hand pump with a gauge to clear the restriction in the capillary and needle, returning them to the tank.
To avoid a pressurized radiological hazard, employees rigorously vetted the use and design of the sampler blowdown assembly. They completed engineering documentation and work instructions that include a pressure test, mockups and senior management evaluations. The team included a vent in the design to prevent the new apparatus from trapping air.
“This idea is not only a great example of team ingenuity and creativity to solve a problem, but it also equates to a safer activity for those performing this work," Miller said.
Source: U.S. Dept. of Energy, Office of Environmental Management
