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Containment & drainage sumps

A plant has many low-lying drainage reservoirs known as sumps. Small sumps include pump enclosures and tank rupture basins that contain leakage. The reactor’s large, containment sump is an essential reservoir of the ECCS whose function is to continuously circulate coolant through the reactor once all coolant storage tanks are depleted.


Small sumps are monitored for leak detection with simple, float-operated level switches designed for bracket mounting in floor level sumps or troughs. These switches detect leaks or spills from pumps, valves, vessels, and pipelines. Levels of the large containment sump, or ECCS sump, are monitored during the recirculation phase of residual heat removal when the reactor’s primary coolant system is down.

Consult factory for Nuclear Qualified instruments and specific model codes.