A civil nuclear operator established a lifetime programme with the objective of managing a lifetime issue by reducing surface deposition buildup rates on interfacing systems. This deposition was a suspected causal factor to various safety, environmental, and commercial issues, surface deposition would be reduced by researching the cause, evaluating available data, assessing potential solutions, and making an informed decision on the implementation of site-tailored chemistry regimes with due considerations made to Nuclear and Industrial safety, operations, commercial implications, and the environment. DAS was commissioned to support the programme, leveraging our extensive nuclear safety capabilities to develop an understanding of the issue and cause, undertaking assessments and evaluating options, and providing key information along with proposed solutions that underpinned client-informed decision-making capability. These activities included:
- Determining the Safety Case basis and evidence required to support informed chemistry regime changes, subsequently developing the necessary evidence.
- Research and studies into the chemical species associated with catalysing the rate of deposition formation.
- Design of lab experiments to generate information associated with degradation mechanisms that were not fully understood.
- Empirical data analysis and model development to align research with data analysis and subsequently creating predictive tools.
- Assessment of systems, chemistry regime, and associated interfaces, to identify potential problematic areas with regards to cause and effect.
- Authoring reports containing key information and clarity of the issue, identifying causal relationships, potential options, and proposed solutions.
The work DAS completed enabled the client to deliver appropriately informed decisions on reactor chemistry regime selection. This was achieved through the delivery of several key documents that identified cause and effect relationships, system interfaces and subsequently affected systems and the trade-off associated with benefits and disbenefits for regime selection. This was in addition to any other considerations necessary to justify any change to operations.
