Adjudication of Radiation Alarms on Detained Cargo Containers

Transcription

1 DOE/NV/ Adjudication of Radiation Alarms on Detained Cargo Containers R. Maurer 2, S. Buntman 1, and H. Adams 2 1 Department of Energy, National Nuclear Security Administration, International Emergency Management and Cooperation 2 Remote Sensing Laboratory, National Security Technologies This work was done by National Security Technologies, LLC, under Contract No. DE-AC52-06NA25946 with the U.S. Department of Energy.

2 International Cargo Container Shipments Every year, millions of cargo containers are shipped around the world and pass through radiation portal monitors at international borders, train hubs, and shipping ports. Some trigger radiation alarms which require investigation and adjudication. 2

3 What is the I-RAPTER Port/Customs Course? International Radiological Assistance Program Training for Emergency Response (I-RAPTER) Training course designed for port/customs officers, radiation protection specialists and emergency managers responsible for investigating and adjudicating alarms on cargo containers 3.5 day course (4.5 day with translation); class size (train-the-trainer) Topics covered include basic radiation/health physics, radiological threats, radiation detection, alarm adjudication, hands-on equipment training, PPE, mission planning, and source recovery with realistic field exercises Detection equipment (60 total) - 4 backpacks, 40 pagers, 10 RIIDs, 2 HPGe s, 2 Health Physics kits, 2 tele-probes, PPE kit Integration of Host Country detection capabilities 3

4 Method to Determine Type and Location of Source Point Source Characterize the Radiation Signature Radiological Characterization Map A vehicle or cargo container with a point source may appear as a localized source in dose rate measurements H 0.5 M 1.0 L 0.4 All readings in µsv/h H readings 2 m above ground M readings 1 m above ground L readings 0.3 m above ground 20 ft D o o r M 0.01 M 0.01 M 0.01 Point sources can be inadvertently mixed with other material; an example includes point sources in shipments of scrap metals H 0.8 M 1.5 L 0.7 H 2.1 M 4.5 L 2.4 H 0.8 M 1.6 L 0.8 L

5 Method to Determine Type and Location of Source Distributed Source Characterize the Radiation Signature Radiological Characterization Map H 4.5 M 6.1 L 0.3 H 2.1 M 4.5 L 0.38 H 0.2 M 0.25 L 0.2 H 0.1 L 0.1 A vehicle or cargo container with contaminated products may appear as a distributedsource over part of the container Metals are contaminated in blast furnaces when radioisotopes such as Co-60 are accidently smelted; examples include rebar, water meters and elevator buttons H 6.3 M 6.1 L 0.6 H 6.3 M 8.1 L 1.0 H 4.5 M 8.0 L 0.6 H 5.0 M 8.3 L 1.0 All readings in µsv/h H readings 2 m above ground M readings 1 m above ground L readings 0.3 m above ground H 2.5 L ft H 0.14 M 0.15 L 0.02 D o o r M 0.01 M 0.01 M

6 Method to Determine Type and Location of Source Uniformly Distributed Characterize the Radiation Signature Radiological Characterization Map A vehicle or cargo container filled with NORM may appear as a uniformly distributed source with nearly equal dose rates on all sides Dose rates may decrease near top of container when bulk of NORM at floor to mid-height level; examples include ores, fertilizers and ceramics All readings in µsv/h H readings 2 m above ground M readings 1 m above ground L readings 0.3 m above ground 20 ft D o o r 6

7 Case Study 1 Cargo container departing a port triggers alarm on a radiation portal monitor Secondary inspection reveals Co-60 Characterization indicates a distributed source in back of container RPM Initial Interdiction Secondary Inspection Source Shape from Characterization Map 7

8 Case Study 1 I-RAPTER course conducted with Port and Customs experts The detained container was incorporated into the training and field exercises Experts inspect container to assess safety and health risks Instructors demonstrate assessment techniques and include students in the process Recovery of 102 cases of water meters contaminated with Co-60 Total activity ~37 MBq 8

9 Case Study 2 Cargo container sets off alarm at a shipping port radiation portal monitor Gamma spectroscopy measurements by Customs gives Ra-226 Highest readings in back third, majority of contents removed and surveyed Initial Survey Remaining Contents to be Surveyed Clean Contents Removed

10 Case Study 2 PPE level increased as loose contamination discovered Packaging improvised to address source shape (aluminum bar 1.4 m long) Source was a static eliminator bar with radium paint on one side (~37 MBq) Initial Survey Loose Material Material Removal Final Source and PPE Packaging 10

11 Case Study 3 Container of scrap metal triggers alarm on radiation portal at shipping port Safety assessment conducted by experts including contamination survey Initial results: Ra-226 (~ MBq), neutrons, no external contamination Spectral Identification 1 2 Contamination Survey Door Point Source from Characterization Map 52 Position Estimate 11

12 Case Study 3 I-RAPTER course conducted with Port and Customs experts The detained container was incorporated into the training and exercises Recovery operations led by a multi-national expert team Port Authority, Customs, Ministry Experts, and others Located an orphan RaBe source originating from a density/moisture meter Recovered, packaged, secured, and delivered for final disposition Training Storage Recovery 12

13 Best Practices Develop a recovery plan with contingencies for handling contamination Use methods and procedures to determine type and location of source Develop a characterization map of exterior cargo container signature Outfit and train entry team with safety guidance and appropriate PPE Employ PPE level appropriate for mission to allow responder flexibility Continuously monitor for contamination throughout recovery operation Ensure Health Physics instruments are calibrated and thresholds set Coordinate and incorporate multi-national experts and concepts 13

14 Take Home Message The I-RAPTER Port/Customs course is designed to enhance Partner Nation s radiological/nuclear emergency response capabilities to investigate, adjudicate, and recover radiation sources in cargo shipments. Consider hosting a course or attending one of the courses hosted in the U.S. 14

15 Summary I-RAPTER Port/Customs is a training course designed for port/customs officers, radiation protection specialists and emergency managers responsible for investigating and adjudicating radiation alarms on cargo shipments. information contact: Vince McClelland, Director U.S. DOE/National Nuclear Security Administration International Emergency Management and Cooperation Vince.McClelland@nnsa.doe.gov Steven Buntman, Program Manger U.S. DOE/National Nuclear Security Administration International Emergency Management and Cooperation Steven.Buntman@nnsa.doe.gov Rick Maurer, Principal Scientist U.S. DOE/National Nuclear Security Administration Remote Sensing Laboratory Maurerrj@nv.doe.gov 15