An Alternative Disposal Method for Activated PCB Capacitors N.M. Brachmann F.R. Brumwell S.W. Butala S.Y. Chen J.-J. Cheng Presented at the DOE Accelerator Safety Workshop – SLAC August 18, 2010

IPNS Facility  450 GeV protons on uranium target  neutron beams  Operated from 1981 to 2007  DOE ordered facility shutdown in December 2007  Subsequent activities focused on putting into safe condition  Priority for disposal of PCB materials 2

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PCB Electrical Capacitors  Poly-chlorinated biphenyl oil impregnated = hazardous  Capacitor inventory: Bld 391 (RCS) - 344, each weigh 126 lbs (57.2 kg) Bld 361 (linac) - 40, each weigh 140 lbs (63.5 kg) - 32, miscellaneous sizes (605 kg)  Building 391 and 361 capacitors located in radiological areas 4

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Disposal Options 1.Mixed Waste Facility – EnergySolutions - Clive, Utah -NRC licensed to accept low-level radioactive waste - Awaiting EPA approval for capacitor waste treatment 2.Hazardous Waste Facility – Clean Harbors - Deer Park, TX - EPA approved for TSCA regulated waste -Must meet TX licensing requirements for radioactivity -Requires DOE authorization to be treated and disposed of at a commercial facility 6

Evaluation of Capacitor Activation – Bld Bld. 391 capacitors initially evaluated with portable monitors –All results were background levels 2.Steel and brass hardware removed for gamma spectroscopy –Identified Mn-54, Co-57, Co-60, and Cs-137 –Specific activity ~ 0.4 pCi/g 3.Gamma spectroscopy done for two bulk capacitors that had been located in highest neutron fluence –Identified Na-22, K-40, Mn-54, and Cs-137 –Specific activities = 0.9 pCi/g and 1.9 pCi/g –Specific activities of Na-22, Mn-54 ~ 10% that of K-40, Cs-137 Total estimated activation products activity: < 1.87 microCi 7

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Evaluation of Capacitor Activation – Bld Bld. 361 capacitors initially evaluated with portable monitors –All results were background levels 2.Steel and brass hardware removed for gamma spectroscopy –Identified no radioactive isotopes –Specific activity ~ 0.4 pCi/g 3.Gamma spectroscopy done for two bulk capacitors that had been located closest to 50 MeV linac beam loss point –Identified K-40 and Cs-137, only. –Specific activities = 0.4 pCi/g and 1.4 pCi/g, respectively –Used gamma spec system MDA to estimate Mn-54 and Na-22 Total estimated activation product activity: < 0.38 microCi 9

Texas Department of Health Regulatory Limits Exemption limits 10 RadioisotopeLimit (µCi)Capacitor Content (µCi) Na Mn Co Co

Approval Process for Disposal in Texas  Argonne submitted a report that evaluated the induced radioactivity in PCB capacitors (S. Butala and F. Brumwell)  Clean Harbors anticipated they could accept the capacitors, and forwarded request and report to Texas Department of Health  State concurred that proposed shipments would contain radioactivity below the exemption limits  Clean Harbors submitted a price quote to Argonne which provided basis for significant cost savings 11

ALARA Analysis  RESRAD analysis for both disposal options done by J.-J. Cheng and S.Y. Chen of Argonne  Evaluated landfill disposal of metals following incineration (Clean Harbors) or heat treatment (EnergySolutions)  Worst-case scenario: subsistence farming 30 years post-burial  Maximum individual dose: mrem/year  Estimated collective dose to workers and public: 4E-4 person- rem 12

Requirements for DOE Authorized Release  Per DOE Order , release of property with residual radioactivity must: –Be evaluated, characterized, and if appropriate, decontaminated –Residual radioactivity must be as near background as practical –Releases be certified, verified, documented, and reported  Release of waste to a non-LLRW disposal facility must: –Meet authorized limits that assure public doses << 25 mrem/year –Have authorized release limits approved by DOE –Have protocols for survey and review of clearance –Authorized clearance limits should be coordinated with NRC or Agreement State reps 13

Additional Requirements for RCRA or TSCA Material Authorized limits must: - Be assessed via ALARA process to optimize risk and benefits - Ensure groundwater is protected - Ensure the TSDF not require future remediation - Be acceptable to TSDF authority and applicable State reps 14

Conclusions  First ever authorized release project at Argonne  DOE approved the proposed disposal plan  Successfully working with stakeholders  Capacitors were shipped to Clean Harbors  Following incineration, residues buried in RCRA licensed landfill owned/operated by Clean Harbors  Cost savings versus disposal at mixed waste facility: $950k 15