Radiation. Where it Doesn t Belong [ and places we have found it ] Art Green Radiac Environmental Services

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2 Radiation. Where it Doesn t Belong [ and places we have found it ] Art Green Radiac Environmental Services 2

3 Just Some Basics 1. What are the main types of radiation? 2. What s the difference between dose and dose rate? 3. What s the difference between radiation exposure and radioactive contamination? 3

4 Types of Radiation Alpha-Beta-Gamma Alpha Beta Gamma Paper 3/8 Plastic Lead or Steel 8

5 Dose vs. Dose Rate Dose Rate (micro-r per hour) is the speed at which you accumulate dose Dose rate is measured with survey meters measures ur/hr similar to speed (mph) Radiation Dose (micro-r) is total accumulated dose similar to an odometer 9

6 What is Radioactive Material? A material that contains many unstable atoms that emit radiation 5

7 Examples of Radioactive Materials Granite Countertop Vial of radioactive compound for research or medicine Radon Gas Bananas 6

8 Exposure vs. Contamination 13

9 What is Radiation Exposure? Exposure normally refers to x-ray or gamma ray radiation external to the body. A chest X-ray is an example of radiation exposure. Exposure to radiation alone will not contaminate you. Exposure to radiation at controlled levels is not a hazard. 14

10 Uncontained radioactive material What is Radioactive Contamination? In water In air On a surface Contamination is diluted as it spreads 15

11 Exposure or Contamination? 1. Patient receives a dental x-ray. 2. Patient receives radioactive Iodine-131 therapy at the hospital and goes home. 3. Truck with radioactive packages is driving on the highway. 4. Researcher with a vial of radioisotopes drops it on the floor and it shatters. 17

12 HOW IS RADIATION DETECTED? 12

13 Measuring Gamma Radiation To detect gamma radiation, often a scintillation detector and it can see small changes above background. Example: Ludlum Model 3 meter with a scintillation detector. 24

14 Vehicle Portal Monitor 14

15 Where are Portal Monitors Located? Ports of Entry Metal Scrapyards Solid Waste Transfer Facilities Sanitary Landfills Hospital Loading Docks Regulated Medical Waste Processing Facilities 15

16 USCBP Mobile Monitoring Vehicle 16

17 Does Anyone Recognize This? 17

18 St. Louis Car Co. R-44 Subway Cars The R44 is a New York City Subway car model built from 1971 to 1973 for the BMT,IND & SI Railway. Car length: 75 ft Train length: 4 car train: 300 feet In 2012 these cars were being readied for scrapping for a man-made reef. They were to be stripped of all components that could hang-up a diver and his equipment. They were forwarded to a metal scrap facility for this disassembly. 18

19 At The Scrapyard The cars set off the radiation portal monitor. We were asked to do a radiation survey of the cars. 19

20 Surveying the Cars 20

21 Surveying the Cars 21

22 Synopsis of Survey Results Transformers were found to be a source of high gamma radiation. Under the steel shell, the copper coils were held in place by a cement-like potting material/filler. A gypsum or zirconium based cement had been used by the transformer manufacturer based on heat resistant properties. The minerals in the cement contained high levels of naturally occurring radioactive material (NORM). 22

23 Survey Results 23

24 Final Results In February, 2013, after sampling 36 transformers (20% of the total) and having them analyzed, they were found to have no PCB s and the heavy metals content was well below RCRA criteria. The only hazard was the slightly elevated radiation levels due to Naturally Occurring Radioactive Material, and the transformers were sent to an authorized NORM radioactive waste disposal site. 24

25 Imported Products 25

26 Customs Rules for Radiation Containers Option 1: Importer is responsible for oversight and costs of manipulation. Importer must get approved facility and hazmat team. CBP will send 4 individuals to the approved facility, including a radiation safety officer. Re-export of contaminated materials is required before any clean materials can be accepted. Option 2: Re-export the entire shipment. 26

27 USCBP Contractor Requirements Contractors to perform container manipulation activities on radiological contaminated cargo at a CBP Port(s) must provide: Qualifications and experience NRC/Agreement State radioactive materials license and/or applicable reciprocity agreement(s) List of survey and characterization procedures List of instrumentation Release criteria Handling and packaging procedures for contaminated material Statement of post work survey results 27

28 USCBP Survey in Progress 28

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34 What We Found 34

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42 Suspicion of How Incidents Occurred A foreign steel recycler mistakenly melted a Cobalt-60 or other radiation source in a batch of steel. Steel was sold to various product fabricators. The resulting products with Co-60 (or other RAM) incorporated into their metal matrix have been exported to various consignees in the United States. US Custom s authorities have taken a position of zero radioactivity tolerance for any imported products. No detectable radiation levels are permitted. Note that the RAM is an integral part of the metal and it cannot be removed. This is considered activated material. 42

43 Scrap Steel Delivery in India 43

44 Municipal Solid Waste 44

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50 Description of What We Found This Municipal Solid Waste contained material with patient wipings, garbage, bedding and/or diapers. The radioactive material was excreted by or came in contact with patients who had undergone radioactive tests or treatments using short-lived radioisotopes as tracing material. 50

51 How Did It Get There? Patients receiving tests or treatments are given the following instructions when they are released : Do not throw out tissues, bedding, diapers in normal household waste. Patients sometimes do not follow hospital release guidelines with the radioactive bedding, diapers, etc. going into household waste and then to a municipal solid waste facility triggering radioactive material (portal) monitors. 51

52 Monitoring Processed NYC Sewerage Sludge 52

53 Scrap Metal Yard 53

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57 What is It? As far as we can determine this was a Cs 137 Radioactive Source of significant activity in it s lead shielded source holder. We believe that the source holder with the source was removed from it s original instrument and somehow tossed into a scrapyard undetected. It appears that the object was somehow subject to intense heat which melted the lead and fused the internal source to the lead. How this ended up in a load of scrap steel ( chopped up cars and appliances) for export is beyond all involved parties (USCBP,NJDEP and the scrapyard company). 57

58 Radium Instrument Dials 58

59 Radium Watch and Clock Dials -,,.._ ;: " I I i, I.!., DOT-SP: PA-NJ ' (from Keystone Landfill) 1 x 5-gal. plastic pail. Reading from pail (hottest spot): At contact 1.2 mr/hr At one Foot 0.19 mr/hr Act (estimate) ~ 40 uci 59

60 Radium Watch and Clock Dials 1 x 5-gal. plastic pail. a few dozen faces. Reading from pail (hottest spot): At contact 15.7 mr/hr At one Foot 1.6 mr/hr Act (estimate) ~ 200 uci (possible) 60

61 Questions? 61