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This issue was raised in an AEOD memorandum[1]to NRR and OIE in October 1980 and addressed the problem of flow blockage by Asiatic clams (Corbicula) in redundant safety-related cooling water systems at Arkansas Nuclear One.
This issue has been combined and evaluated with Issue 51, "Proposed Requirements for Improving the Reliability of Open Cycle Service Water Systems."
[1] Memorandum for H. Denton et al. from C. Michelson, "Flow Blockage in Essential Equipment at ANO
Page Last Reviewed/Updated Tuesday, March 24, 2026
Disclaimer: Some of the formatting in NUREG-0933 may not be correct. We are currently working on fixing the formatting.
Page Last Reviewed/Updated Tuesday, March 24, 2026
