4th Response Submittal to the EPA 

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Error Description Correction Originator Responsib

1 EPA Comment 

1-23-13 Missing Reference. Appendix SOTERM, Figure SOTERM-7 caption cites Altmaier (2011) but this reference is missing from the reference list. Please provide this reference.

This is a typographical error in Appendix SOTERM. The text will be corrected to read “Altmaier et al., 2008” which is already included as a reference in Appendix SOTERM, given below. The requested reference is included in Enclosure 2. Figure SOTERM-7 is based on Figure 5 in this reference and shows the highest three CaCl2 concentrations shown in the published Figure.This typographical error has been added to Enclosure 4, CRA-2014 Errata 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 of ternary Ca-M-OH complexes,” Radiochimica Acta 96, (2008).

EPA LANL-D. Re

2 EPA Comment 

1-G-1 Reference Appendix QAPD-2014 Not Provided. CRA-2014 Section 23, Models and Computer Codes, Section 23.5.7 states, "The DOE's quality assurance program, as applied to the CRA-2014, is contained in Appendix QAPD-2014." The appendix has not been provided. Please provide this document.

There was not an Appendix QAPD-2014 in the CRA-2014; therefore, the statement above is a typographical error in CRA-2014 Section 23.5.7. The reference to Quality Assurance Program Document (QAPD) will be added to Section 23 References and the text will be corrected to read, “The DOE's quality assurance program, as applied to the CRA-2014, is contained in the Quality Assurance Program Document (U.S. DOE 2010)." The QAPD is already included as a reference in the CRA-2014; however, a copy of the QAPD is included in Enclosure 2.This typographical error has been added to Enclosure 4, CRA-2014 Errata Tracking .

EPA SNL-G. Safl

3 EPA Comment 

2-55-1 Incorrect Reference. IGP-2014, Section IGP-2.1 makes reference to 194.55(b)(1), should this be 194.54(b)(1) “Existing boreholes...”?

This is a typographical error in Appendix IGP-2014. The text will be corrected to read “Existing boreholes, as required by 40 CFR § 194.54(b)(1)...”.This typographical error has been added to Enclosure 4, CRA-2014 Errata Tracking .

EPA SNL-S. Wag

CRA‐2014 Errata Tracking

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4th Response Submittal to the EPA 

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Error Description Correction Originator Responsib

CRA‐2014 Errata Tracking

4 EPA Comment 

2-23-2 Provide an Update of the Derivation of the Shaft Properties at the Repository Horizon. "...In the CRA 2014 PA, however, it appears the material properties of the shaft at the repository horizon have not been updated to reflect the change. Please confirm this and identify how the properties would change to reflect the change in the panel closure design."

The corrected length of the northernmost set of panel closures will be implemented in future PA calculations and will be tracked in Enclosure 4, CRA-2014 Errata Tracking .

EPA SNL-T. Zeitl

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4th Response Submittal to the EPA 

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Error Description Correction Originator Responsib

CRA‐2014 Errata Tracking

5 EPA Comment

2-32-S7 FEP W3 Heterogeneity of Waste Forms. The screening argument citation of the CCA as the source of information on the heterogeneity of waste forms ignores changes that have occurred in the past 15 years, including supercompacted waste and mingling RH waste in shielded containers with CH waste. Please update the information to reflect current waste forms.

SCR-6.1.2.1.2 Summary of New InformationThe waste inventory used for the CRA-2014 PA calculations has been updated as provided in Kicker and Zeitler (2013). Since these FEPs are accounted for in PA, inventory-related parameters may differ from those used in previous PAs; however, the screening decisions have not changed and these FEPs are represented in PA calculations. The EPA approved the use of the shielded RH container as an allowable disposal container in WIPP (Edwards 2013). The impacts of this container upon WIPP performance were evaluated in Dunagan et al. (2007).SCR-6.1.2.1.3 Screening ArgumentWaste characteristics, comprising the waste inventory and heterogeneity of waste forms, are described in the CCA, Appendix BIR. The waste inventory is accounted for in PA calculations in deriving the dissolved actinide source term and gas generation rates. The distribution of contact-handled transuranic (CH-TRU) and remote-handled transuranic (RH-TRU) waste within the repository leads to room-scale heterogeneity of the waste forms, which is accounted for in PA calculations when considering the potential activity of waste material encountered during inadvertent borehole intrusion (Appendix PA-2014, Section PA-3.8). The DOE implements waste heterogeneity in waste forms through the assumption of random placement of TRU waste in the repository. This assumption includes all waste container forms and types. Details regarding the implementation of this assumption are provided in the CRA-2009, Appendix MASS-2009, Section MASS-21.0. This implementation methodology has not changed as a result of the addition of the shielded RH-waste container. This change has been added to Enclosure 4, CRA-2014 Errata 

Tracking .

EPA SNL/PIRUR.Kirkes 

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4th Response Submittal to the EPA 

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Error Description Correction Originator Responsib

CRA‐2014 Errata Tracking

6 EPA Comment 

2-32-S8 FEP W5 Container Material Inventory.Please supplement the screening argument with an explanation of the implementation in PA of the material inventory of shielded 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 inventory for the CRA-2014 have been updated as detailed in Van Soest (2012). The EPA approved the use of the shielded RH container as an allowable disposal container in WIPP (Edwards 2013). The impacts of this container upon WIPP performance were evaluated in Dunagan et al. (2007). SCR-6.1.3.2.3 Screening ArgumentThe container material inventory is described in Van Soest (2012) and is accounted for in PA calculations through the estimation of gas generation rates (see Appendix PA-2014, Section PA-4.2.5). In the CCA, Appendix WCL, a minimum quantity of metallic Fe was specified to ensure sufficient reactants to reduce radionuclides to lower and less soluble oxidation states. This requirement is met as long as there are no substantial changes in container materials. The inventory used for the CRA-2014 contains 3.69 x 107 kg of steel in packaging (includes containers) materials. This value is up slightly from 3.59 x 107 kg reported in 2008 (Van Soest 2012). Modeling assumptions related to the implementation of waste container materials can be found in Appendix MASS-2014, Table MASS-5.This change has been added to Enclosure 4, CRA-2014 Errata 

Tracking .

EPA SNL/PIRUR.Kirkes 

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4th Response Submittal to the EPA 

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Error Description Correction Originator Responsib

CRA‐2014 Errata Tracking

7 EPA Comment 

2-32-S15 FEP W28 Nuclear Explosions. Please modify the screening argument to address whether, in addition to “a reduction of TRU radionuclides from previous estimates”, the quantities of fissile radionuclides have also been reduced.

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 the basis 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 inventory information as presented in Kicker and Zeitler (2013). This new information does not change the screening argument or decision for this FEP.SCR-6.3.3.2.3 Screening ArgumentNuclear explosions have been eliminated from PA calculations on the basis of low probability of occurrence over 10,000 yrs. For a nuclear explosion to occur, a critical mass of Pu would have to undergo rapid compression to a high density. Even if a critical mass of Pu could form in the system, there is no mechanism for rapid compression. Inventory information used for the CRA-2014 is presented in Kicker and Zeitler (2013). The updated inventory information for the CRA2014 shows a reduction of TRU radionuclides from previous estimates. Fissile radionuclides have reduced from approximately 3.1 million curies for the PABC-2009 to 2.7 million curies for the CRA2014. Thus, current criticality screening arguments are conservatively bounded by the previous CCA screening arguments (Rechard et al. 1996, 2000, and 2001).This change has been added to Enclosure 4, CRA-2014 Errata 

Tracking .

EPA SNL/PIRUR.Kirkes 

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4th Response Submittal to the EPA 

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Error Description Correction Originator Responsib

CRA‐2014 Errata Tracking

8 EPA Comment 

2-32-S19 FEP W45 Effects of Temperature on Microbial Gas Generation. Please modify the screening argument to acknowledge the reduced thermal impact of seal concrete hydration because of the elimination of additional explosion walls and 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 of concrete from the panel closure systems. Because the new panel closures will be constructed of mined salt, the overall mass of concrete emplaced within the repository will be significantly decreased. More importantly, the emplacement of any constructed element (e.g., shaft seals) of the repository will be done at or before repository closure. Therefore, any increase in temperature due to concrete hydration will have abated by the time AICs are assumed to no longer prevent drilling into the repository.The revised text has been added to Enclosure 4, CRA-2014 Errata Tracking.

EPA SNL/PIRUR.Kirkes 

9 EPA Comment 

2-32-S20 FEP W53 Radiolysis of Cellulose. The reported reason for the screening argument update is not consistent between Table SCR-1, where the update is due to new radionuclide inventory, and Section SCR-6.5.1.7.2 where the update is due to new cellulose inventory. The screening argument in Section SCR-6.5.1.7.3 refers only to the new radionuclide inventory. Please reconcile the information.

This is a revision to Appendix SCR-2014. The revised text of Section SCR-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 all TRU radionuclides which indicate that radiolysis of cellulose will not be a significant process. The screening argument and decision are not affected by this change in inventory information.This change has been added to Enclosure 4, CRA-2014 Errata 

Tracking .

EPA SNL/PIRUR.Kirkes 

End of CRA-2014 Errata Tracking

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