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Radiation Protection

ISCORS Study of Wastewater Treatment Plant TENORM

A multi-year study conducted by EPA and other federal agencies who work with the Interagency Steering Committee on Radiation Standards (ISCORS)Exit provided detailed information on radionuclides in Publicly-Owned Treatment Works (POTWs). The study was conducted in several phases:

Sewage Sludge POTW Pilot Survey

ISCORS established a subcommittee to examine radioactivity found in sewage sludge and the ash from its incineration. The subcommittee’s first project was to conduct a pilot survey to determine the levels of radioactivity at nine POTWs. The subcommittee found that sources of radiation in sewage sludge and ash could be from Nuclear Regulatory Commission (NRC) or Agreement States licensees’ discharges, unintentional or unregulated industrial discharges and Technologically Enhanced Naturally Occurring Radioactive Material (TENORM). View and download the report, Joint NRC/EPA Sewage Sludge Radiological Survey:  Survey Design & Test Site Results.

Sewage Sludge POTW National Survey

Following completion of the pilot study, ISCORS undertook a nationwide survey. Three reports describing the national-level findings are available below.

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