A ‘Catch 22’ is defined as a “difficult situation for which there is no easy or possible solution.” That is precisely what members of USA fleet member Susquehanna Station’s Fire Protection (FP) System Recovery Team faced when looking for solutions to degraded FP piping in the Circulating Water Pump House (CWPH).
The main issue faced by the team? How to solve the issue of degraded piping within the CWPH, as evidenced by pinhole leaks resulting from Microbiologically Induced Corrosion, or MIC. For clarification, the industry understands MIC as corrosion that occurs on piping from bacteria present in Raw Water Systems.
While the team’s preferred option from the start was pipe replacement, it also faced the additional challenge of not being able to isolate the FP lines because of debris buildup in isolation valves. Without isolation, the only option was to drain down the FP system yard loop, which would increase station risk and involve significant coordination and resources.
After reviewing multiple options – including composite pipe wrap, multiple hot taps and a system drain down – by using the Station’s Technical Decision Making (TDM) process, the team selected the installation of two “InsertValves” as the solution (provided by TEAM Industrial Services). This technology provided the ability to remove a section of pipe with the system in service (similar to a hot tap), and then “insert” a fully functioning isolation valve in its place. This provided the benefit of pipe isolation without taking the system out of service.
“With a number of options available, the TDM process really helped us to narrow down the preferred solution,” said Station System Engineer Ben Hyduk. “In addition to the TDM process, benchmarking with others – including USA Stations – helped us to confirm successful use of this technology in the industry.”
The solution was sponsored as a fast track mod by Programs Engineering Manager Darren Deretz, prioritized by the Station Health Committee, and completed by Site Design. In parallel, parts and services were procured and preparation work completed through the teamwork of numerous groups including Maintenance – MMC, Site Design, Field Project Management, Procurement, and Day and Zimmerman.
Valve installations were sponsored into the schedule with support of Work Management, and the first valve was inserted on the Unit 2 FP line during the week of November 14. Since this initial installation was a first of a kind for Susquehanna, it was handled as a SICT/E (Significant Infrequent or Complex Test/Evolution) with accompanying briefing and controls. After the Unit 2 valve installation, an After Action Review was conducted and learnings applied to the Unit 1 valve installation, which was successfully completed one month later.
“Our success with this technology provides us another design option that we can implement on water systems as required to maintain Equipment Reliability, one of our five Focus Areas,” said Senior Engineer Lori Fuller. Field Project Manager Keith Mattern added, “With completion of this job, not only is the plant in a safer condition with the ability to positively isolate the FP lines, but it also provides the ability to proceed with the piping replacement.”
The first part of the FP Pipe replacement is planned for early first quarter 2015 with the remaining sections to be done in conjunction with the Fire Pump Replacement project later this year. A broader project team has also been established to address degraded piping issues with all of the main Raw Water Systems at the Station.
Team Industrial Services Field Technician evaluates work in progress at the Circulating Water Pump House.