4thResponseSubmittaltotheEPAEnclosure4Error#ErrorDescription Correction Originator Responsibility StatusDateofCompletion1 EPA Comment1-23-13 Missing Reference.Appendix SOTERM, Figure SOTERM-7caption cites Altmaier (2011) but thisreference is missing from the referencelist. Please provide this reference.This is a typographical error in Appendix SOTERM. The text will becorrected to read “Altmaier et al., 2008” which is already included asa reference in Appendix SOTERM, given below. The requestedreference is included in Enclosure 2. Figure SOTERM-7 is based onFigure 5 in this reference and shows the highest three CaCl2concentrations shown in the published Figure.This typographical error has been added to Enclosure 4,CRA-2014Errata Tracking.Reference:Altmaier M., Neck, V., Fanghänel, T., “Solubility of Zr(IV), Th(IV)and Pu(IV) hydrous oxides in CaCl2 solutions and the formation ofternary Ca-M-OH complexes,” Radiochimica Acta 96, (2008).EPA LANL-D. Reed Included infirst responsesubmittal toEPASubmitted toEPA in firstresponse,1/28/152 EPA Comment1-G-1 Reference Appendix QAPD-2014Not Provided.CRA-2014 Section 23, Models andComputer Codes, Section 23.5.7 states,"The DOE's quality assurance program, asapplied to the CRA-2014, is contained inAppendix QAPD-2014." The appendixhas not been provided. Please provide thisdocument.There was not an Appendix QAPD-2014 in the CRA-2014; therefore,the statement above is a typographical error in CRA-2014 Section23.5.7. The reference to Quality Assurance Program Document(QAPD) will be added to Section 23 References and the text will becorrected to read, “The DOE's quality assurance program, as appliedto the CRA-2014, is contained in the Quality Assurance ProgramDocument (U.S. DOE 2010)." The QAPD is already included as areference in the CRA-2014; however, a copy of the QAPD is includedin Enclosure 2.This typographical error has been added to Enclosure 4,CRA-2014Errata Tracking.EPA SNL-G. Safley Included infirst responsesubmittal toEPASubmitted toEPA in firstresponse,1/28/153 EPA Comment2-55-1 Incorrect Reference.IGP-2014, Section IGP-2.1 makesreference to 194.55(b)(1), should this be194.54(b)(1) “Existing boreholes...”?This is a typographical error in Appendix IGP-2014. The text will becorrected to read “Existing boreholes, as required by 40 CFR §194.54(b)(1)...”.This typographical error has been added to Enclosure 4,CRA-2014Errata Tracking.EPA SNL-S. Wagner Included inthird responsesubmittal toEPASubmitted toEPA in thirdresponse, 4/8/15CRA‐2014ErrataTracking14thResponseSubmittaltotheEPAEnclosure4Error#ErrorDescription Correction Originator Responsibility StatusDateofCompletionCRA‐2014ErrataTracking4 EPA Comment2-23-2 Provide an Update of theDerivation of the Shaft Properties at theRepository Horizon."...In the CRA 2014 PA, however, itappears the material properties of theshaft at the repository horizon have notbeen updated to reflect the change. Pleaseconfirm this and identify how theproperties would change to reflect thechange in the panel closure design."The corrected length of the northernmost set of panel closures will beimplemented in future PA calculations and will be tracked inEnclosure 4,CRA-2014 Errata Tracking.EPA SNL-T. Zeitler Included infourthresponsesubmittal toEPASubmitted toEPA in fourthresponse24thResponseSubmittaltotheEPAEnclosure4Error#ErrorDescription Correction Originator Responsibility StatusDateofCompletionCRA‐2014ErrataTracking5 EPA Comment2-32-S7 FEP W3 Heterogeneity of WasteForms.The screening argument citation of theCCA as the source of information on theheterogeneity of waste forms ignoreschanges that have occurred in the past 15years, including supercompacted wasteand mingling RH waste in shieldedcontainers with CH waste. Please updatethe information to reflect current wasteforms.SCR-6.1.2.1.2 Summary of New InformationThe waste inventory used for the CRA-2014 PA calculations has beenupdated as provided in Kicker and Zeitler (2013). Since these FEPsare accounted for in PA, inventory-related parameters may differ fromthose used in previous PAs; however, the screening decisions have notchanged and these FEPs are represented in PA calculations. The EPAapproved the use of the shielded RH container as an allowabledisposal container in WIPP (Edwards 2013). The impacts of thiscontainer upon WIPP performance were evaluated in Dunagan et al.(2007).SCR-6.1.2.1.3 Screening ArgumentWaste characteristics, comprising the waste inventory andheterogeneity of waste forms, are described in the CCA, AppendixBIR. The waste inventory is accounted for in PA calculations inderiving the dissolved actinide source term and gas generation rates.The distribution of contact-handled transuranic (CH-TRU) andremote-handled transuranic (RH-TRU) waste within the repositoryleads to room-scale heterogeneity of the waste forms, which isaccounted for in PA calculations when considering the potentialactivity of waste material encountered during inadvertent boreholeintrusion (Appendix PA-2014, Section PA-3.8). The DOEimplements waste heterogeneity in waste forms through theassumption of random placement of TRU waste in the repository.This assumption includes all waste container forms and types. Detailsregarding the implementation of this assumption are provided in theCRA-2009, Appendix MASS-2009, Section MASS-21.0. Thisimplementation methodology has not changed as a result of theaddition of the shielded RH-waste container.This change has been added to Enclosure 4,CRA-2014 ErrataTracking.EPA SNL/PIRUR.KirkesIncluded infourthresponsesubmittal toEPASubmitted toEPA in fourthresponse34thResponseSubmittaltotheEPAEnclosure4Error#ErrorDescription Correction Originator Responsibility StatusDateofCompletionCRA‐2014ErrataTracking6 EPA Comment2-32-S8 FEP W5 Container MaterialInventory.Please supplement the screening argumentwith an explanation of the implementationin PA of the material inventory ofshielded containers containing RH waste.SCR-6.1.3.2 FEP Number: W5FEP Title: Container Material InventorySCR-6.1.3.2.1 Screening Decision: UPThe Container Material Inventory is accounted for in PA calculations.SCR-6.1.3.2.2 Summary of New InformationThe masses of container materials associated with the waste inventoryfor the CRA-2014 have been updated as detailed in Van Soest (2012).The EPA approved the use of the shielded RH container as anallowable disposal container in WIPP (Edwards 2013). The impactsof this container upon WIPP performance were evaluated in Dunaganet al. (2007).SCR-6.1.3.2.3 Screening ArgumentThe container material inventory is described in Van Soest (2012) andis accounted for in PA calculations through the estimation of gasgeneration rates (see Appendix PA-2014, Section PA-4.2.5). In theCCA, Appendix WCL, a minimum quantity of metallic Fe wasspecified to ensure sufficient reactants to reduce radionuclides tolower and less soluble oxidation states. This requirement is met aslong as there are no substantial changes in container materials. Theinventory used for the CRA-2014 contains 3.69 x 107 kg of steel inpackaging (includes containers) materials. This value is up slightlyfrom 3.59 x 107 kg reported in 2008 (Van Soest 2012). Modelingassumptions related to the implementation of waste containermaterials can be found in Appendix MASS-2014, Table MASS-5.This change has been added to Enclosure 4,CRA-2014 ErrataTracking.EPA SNL/PIRUR.KirkesIncluded infourthresponsesubmittal toEPASubmitted toEPA in fourthresponse44thResponseSubmittaltotheEPAEnclosure4Error#ErrorDescription Correction Originator Responsibility StatusDateofCompletionCRA‐2014ErrataTracking7 EPA Comment2-32-S15 FEP W28 Nuclear Explosions.Please modify the screening argument toaddress whether, in addition to “areduction of TRU radionuclides fromprevious estimates”, the quantities offissile radionuclides have also beenreduced.SCR-6.3.3.2 FEP Number: W28FEP Title: Nuclear ExplosionsSCR-6.3.3.2.1 Screening Decision: SO-PNuclear Explosions have been eliminated from PA calculations on thebasis of low probability of occurrence over 10,000 yrs.SCR-6.3.3.2.2 Summary of New InformationThis FEP has been updated to include the most recent inventoryinformation as presented in Kicker and Zeitler (2013). This newinformation does not change the screening argument or decision forthis FEP.SCR-6.3.3.2.3 Screening ArgumentNuclear explosions have been eliminated from PA calculations on thebasis of low probability of occurrence over 10,000 yrs. For a nuclearexplosion to occur, a critical mass of Pu would have to undergo rapidcompression to a high density. Even if a critical mass of Pu couldform in the system, there is no mechanism for rapid compression.Inventory information used for the CRA-2014 is presented in Kickerand Zeitler (2013). The updated inventory information for the CRA2014 shows a reduction of TRU radionuclides from previousestimates. Fissile radionuclides have reduced from approximately 3.1million curies for the PABC-2009 to 2.7 million curies for the CRA2014. Thus, current criticality screening arguments are conservativelybounded by the previous CCA screening arguments (Rechard et al.1996, 2000, and 2001).This change has been added to Enclosure 4,CRA-2014 ErrataTracking.EPA SNL/PIRUR.KirkesIncluded infourthresponsesubmittal toEPASubmitted toEPA in fourthresponse54thResponseSubmittaltotheEPAEnclosure4Error#ErrorDescription Correction Originator Responsibility StatusDateofCompletionCRA‐2014ErrataTracking8 EPA Comment2-32-S19 FEP W45 Effects ofTemperature on Microbial GasGeneration.Please modify the screening argument toacknowledge the reduced thermal impactof seal concrete hydration because of theelimination of additional explosion wallsand the Option D monolith.This is a revision to Appendix SCR-2014, Section SCR-6.5.1.1.3.1.The revised text has been changed to read:This thermal rise is considered bounding due to the elimination ofconcrete from the panel closure systems. Because the new panelclosures will be constructed of mined salt, the overall mass ofconcrete emplaced within the repository will be significantlydecreased. More importantly, the emplacement of any constructedelement (e.g., shaft seals) of the repository will be done at or beforerepository closure. Therefore, any increase in temperature due toconcrete hydration will have abated by the time AICs are assumed tono longer prevent drilling into the repository.The revised text has been added to Enclosure 4, CRA-2014 ErrataTracking.EPA SNL/PIRUR.KirkesIncluded infourthresponsesubmittal toEPASubmitted toEPA in fourthresponse9 EPA Comment2-32-S20 FEP W53 Radiolysis ofCellulose.The reported reason for the screeningargument update is not consistent betweenTable SCR-1, where the update is due tonew radionuclide inventory, and SectionSCR-6.5.1.7.2 where the update is due tonew cellulose inventory. The screeningargument in Section SCR-6.5.1.7.3 refersonly to the new radionuclide inventory.Please reconcile the information.This is a revision to Appendix SCR-2014. The revised text of SectionSCR-6.5.1.7.2 has been changed to read:SCR-6.5.1.7.2 Summary of New InformationThis FEP has been updated with new waste inventory data.Decreasing waste inventory values lower the overall activity for allTRU radionuclides which indicate that radiolysis of cellulose will notbe a significant process. The screening argument and decision are notaffected by this change in inventory information.This change has been added to Enclosure 4,CRA-2014 ErrataTracking.EPA SNL/PIRUR.KirkesIncluded infourthresponsesubmittal toEPASubmitted toEPA in fourthresponseEnd of CRA-2014 Errata Tracking6