Waste sampling and verification

NUCP 2311 Radioactive Waste Management and Disposal

Verify Waste

• When waste containers arrive at a disposal facility, how can one verify what is in the container– Open container and look through it– Take the word of the generator– Check it through various methods

Acceptance Criteria and Certification

• Waste cannot have the following characteristics:– Gas generation– Combustibility– Dispersible– Explosive or compressed gases– Pyrophoric materials

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Acceptance Criteria and Certification

• Things to Verify:

– Toxic or corrosive compounds– Proper Waste containers– Proper Waste package handling– Proper Waste package weight– Proper Waste package size

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Acceptance Criteria and Certification

• Things to Monitor:

– Surface dose rate– Surface contamination– Thermal power– Criticality– Documentation

Acceptance Criteria and Certification

• Before the waste leaves the generator• Waste needs to be– Sampled– Containerized and sealed– Labeled– Manifested– Copy of all this needs to be sent to the waste

facility for them to review and approve thewaste

Package Certification• Multiple Test Methods

– Gamma spectroscopy– X-ray techniques including fluoroscopy– Passive computed tomography– Active computed tomography– Combinations of these

• Newest approach is to use active and passive computed tomography– Employs multiple detectors– May employ multiple sources

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Single HPGe Detector A&PCT System

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Multiple Detector Configuration and Emission Acceptance Angles

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Multiple Horizontal In-Line Detectors and Sources

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Multiple Rotated Detectors and Single Source A&PCT System

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Tomographic Gamma Scanning• Developed as a prototype

at LANL.• Used for both 30- and 55-

gallon drums.• Uses gamma-ray source

and opposing detector.• Three-dimensional images

generated.

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Stored Waste Examination Pilot Plant (SWEPP)

Used for CH-TRU waste in 55-gallon drums.

Six HPGe detectors and Eu-152 sources.

Automated drum transport system.

Used with passive-active neutron system.

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The Stored Waste Examination Pilot Plant (SWEPP) is a facility at the Idaho National Laboratory for nondestructively examining containers of radioactive waste to determine if they meet criteria to be stored at the Waste Isolation Pilot Plant. SWEPP is part of the Radioactive Waste Management Complex, located southwest of EBR-I.

- Wikipedia text (10/11/06)

Passive-Active Neutron Assay System

• Pulsed with neutrons to induce fission.

• Uses a polyethylene moderator.• Has the capability to measure

neutrons from spontaneous fissions.• Enhanced capability using a gamma-

scan technique.

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Combined Thermal/Epithermal Neutron (CTEN) Waste Assay

• Uses differential die-away technique similar to PAN system

• Uses graphite as moderator• Wide dynamic range of assay• Used to certify drums classed

as “too low to assay.”

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Transuranic waste or "TRU waste" consists of materials resulting from the research and production of nuclear weapons. Most waste that is coming to the WIPP consists of rags, clothing, tools and other such items contaminated with radioactive elements, mostly plutonium.

Drum Inspection Scans

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Questions

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