Answer to Question #3180 Submitted to "Ask the Experts"

Depending on the volume of waste entering your facility, you could use a relatively inexpensive handheld "micro-R" type survey instrument or install small crystal or large plastic scintillator portal monitors. Once you identify radioactivity is present, you'll need to identify what is present, which will require a portable multichannel analyzer (MCA). Many facilities use a consultant if alarms are infrequent, as an MCA is expensive and may not be needed on a routine basis. The HPS Affiliate Member listing and Buyer's Guide would be places on this site to find vendors to bid on such equipment.

There are two very good sources of information on this subject. The first is the National Council on Radiation Protection and Measurements.

The NCRP Report No. 141 on "Managing Potentially Radioactive Scrap Metal" is a 224-page report with text, background material, references, and an Appendix B on Radiation Detection and Surveillance. Report No. 141 starts with an Executive Summary followed by an Introduction and sections on Sources and Inventories and Characteristics of Potentially Radioactive Scrap Metal, Management Considerations, Developing Release Standards, Radiation Protection in Scrap Metal Recycling, Protection Against Orphan Source Contamination, and Findings and Recommendations. The most likely scenario is that you'll receive scrap metal or process fluid sludge with technologically enhanced naturally occurring radioactive material (TENORM).

The second source of information would be the Pennsylvania Department of Environmental Protection's  Bureau of Radiation Protection (PA DEP's BRP). I believe this state is the first in the nation to require all solid waste disposal and processing facilities (that is, some 150 RCRA D landfills, transfer facilities, and incinerators) to install radiation monitoring equipment and to develop a Radiation Protection "Action Plan" should they get an alarm. PA DEP's BRP has taken a very practical approach to a quagmire of federal and state regulations related to regulated and unregulated radioactive material that might trip an alarm and established a 10 mircoroentgen per hour alarm set point (with a ¹³⁷Cs standard) at the detector element. For details on the PA DEP's BRP regulations and guidance, go to its Radiation Control Division page or the Monitoring for Radioactive Materials in Solid Waste page.

David J. Allard, CHP