Draft Report for Comment: “Documentation and Applications of the Reactive Geochemical Transport Model RATEQ,” NUREG/CR-6871, 22730-22731 [E5-2072]

Download as PDF 22730 Federal Register / Vol. 70, No. 83 / Monday, May 2, 2005 / Notices November 2003 and is available on the ISCORS Web site at https:// www.iscors.org. The Subcommittee also undertook a dose assessment to help assess the potential threat that these materials may pose to human health. The first final report that we are issuing, ‘‘ISCORS Assessment of Radioactivity in Sewage Sludge: Modeling to Assess Radiation Doses’’ (ISCORS Technical Report 2004–03, NUREG–1783, EPA 832–R– 03–002A, DOE/EH–0670), describes the methodology and results of the dose modeling effort. The radionuclides considered were based on the results of the ISCORS survey, and include manmade and naturally-occurring isotopes. The general approach used in the report is a standard one that consists essentially of two steps. First, seven scenarios were constructed to represent typical situations in which members of the public or POTW workers are likely to be exposed to sludge. Second, assuming a unit specific activity of a radionuclide in dry sludge, environmental transport models were employed to obtain doses. A draft of this report was published for peer review and public comment in November 2003. Changes were made, as appropriate, to address comments in developing the final report. The other major task of the Subcommittee was to develop recommendations for POTW operators. The second final report being issued, ‘‘ISCORS Assessment of Radioactivity in Sewage Sludge: Recommendations on Management of Radioactive Materials in Sewage Sludge and Ash at Publicly Owned Treatment Works’’ (ISCORS Technical Report 2004–04, DOE/EH– 0668, EPA 832-R–03–002B), is for use by POTW operators in evaluating whether the presence of radioactive materials in sewage sludge could pose a threat to the health and safety of POTW workers or the general public. A draft of this report was published for public comment in November 2003. Changes were made, as appropriate, to address comments in developing the final report. Based on the survey and dose modeling, ISCORS concludes that the levels of radioactive materials detected in sewage sludge and ash in the ISCORS survey indicate that, at most POTWs, radiation exposures to workers or to the general public are not likely to be a concern. ADDRESSES: The two ISCORS reports on radioactivity in sewage sludge and ash being issued are available electronically from the ISCORS Web page at: https:// www.iscors.org. Hard copies may also be VerDate jul<14>2003 19:05 Apr 29, 2005 Jkt 205001 obtained by calling or writing to Duane Schmidt, U.S. Nuclear Regulatory Commission, NMSS/DWMEP/DCD, MS: T–7E18, Washington, DC 20555–0001, (301) 415–6919, or dws2@nrc.gov; or to Robert Bastian, U.S. Environmental Protection Agency, Office of Wastewater Management (4204M), Rm. 7220B EPA EAST, 1200 Pennsylvania Ave., NW. Washington, DC 20460, (202) 564–0653, or bastian.robert@epa.gov. FOR FURTHER INFORMATION, CONTACT: Duane Schmidt, U.S. Nuclear Regulatory Commission, NMSS/ DWMEP/DCD, MS: T–7E18, Washington, DC 20555, telephone (301) 415–6919, fax (301) 415–5398, e-mail dws2@nrc.gov; or Robert Bastian, U.S. Environmental Protection Agency, Office of Wastewater Management (4204M), Rm. 7220B EPA EAST, 1200 Pennsylvania Ave., NW., Washington, DC 20460, telephone (202) 564–0653, fax (202) 501–2397, e-mail bastian.robert@epa.gov. Dated at Rockville, Maryland, this 22nd day of April, 2005. For The U.S. Nuclear Regulatory Commission. Scott Flanders, Deputy Director, Division of Waste Management and Environmental Protection, Office of Nuclear Material Safety and Safeguards. [FR Doc. E5–2071 Filed 4–29–05; 8:45 am] BILLING CODE 7590–01–P NUCLEAR REGULATORY COMMISSION Draft Report for Comment: ‘‘Documentation and Applications of the Reactive Geochemical Transport Model RATEQ,’’ NUREG/CR–6871 Nuclear Regulatory Commission. ACTION: Notice of availability and request for comments. AGENCY: Background: The U.S. Nuclear Regulatory Commission (NRC) uses environmental models to evaluate the potential release of radionuclides from NRC-licensed sites. In doing so, the NRC recognizes that, at many sites, groundwater-related pathways could contribute significantly to the potential dose received by members of the public. Consequently, consistent with its mission to protect the health and safety of the public and the environment, the NRC uses contaminant transport models to predict the locations and concentrations of radionuclides in soil as a function of time. Through this notice, the NRC is seeking comment on documentation of a subsurface transport PO 00000 Frm 00104 Fmt 4703 Sfmt 4703 model developed for the NRC by the U.S. Geological Survey (USGS) for realistic transport modeling at sites with complex chemical environments. Because many radionuclides temporarily attach, or adsorb, to the surfaces of soil particles, their mobility is reduced compared to that of compounds that move with the groundwater without interacting with solid surfaces. As a result, most subsurface-transport models used by the NRC and its licensees estimate the effects of the anticipated interactions between radionuclides and solids in the ground. Toward that end, these subsurface-transport models use a ‘‘distribution coefficient,’’ which is assumed to be constant and reflects the proportion of radionuclide in the groundwater compared to the radionuclide associated with the solids in the ground. These distribution coefficients are widely used, and consequently, the relevant literature documents ranges of their values for various soil types and radionuclides. However, the documented ranges can be very large because the chemical reactions that cause radionuclides to attach to solids are very sensitive to water chemistry and soil mineralogy. As a result, uncertainties in the parameters used to characterize the adsorption of radionuclides in soils have been identified as a major source of uncertainty in decommissioning, uranium recovery, and radioactive waste disposal cases evaluated by the NRC. Surface-complexation and ionexchange models offer a more realistic approach to considering soilradionuclide interactions in performance-assessment models. These models can also account for variable chemical environments that might affect such interactions. The subject report, prepared for the NRC by the USGS, describes the theory, implementation, and examples of use of the RATEQ computer code, which simulates radionuclide transport in soil and allows the use of surface-complexation and ion-exchange models to calculate distribution coefficients based on actual site chemistry. The RATEQ code will help the NRC staff define realistic site-specific ranges of the distribution coefficient values used to evaluate NRC-licensed sites. In site-remediation cases, such as restoration of the groundwater aquifer in and around uranium in-situ leach mining facilities, the RATEQ code can aid in the estimation of restoration costs by estimating the volume of treatment water needed to restore sites to acceptable environmental conditions. E:\FR\FM\02MYN1.SGM 02MYN1 Federal Register / Vol. 70, No. 83 / Monday, May 2, 2005 / Notices Solicitation of Comments: The NRC seeks comments on the report and is especially interested in comments on the value of the report to users who run the RATEQ code and are familiar with the types of complex chemical environments that complicate many remediation projects. Comment Period: The NRC will consider all written comments received before August 12, 2005. Comments received after August 12, 2005, will be considered if time permits. Comments should be addressed to the contact listed below. Availability: An electronic version of the report is available in Adobe Portable Document Format at https:// www.nrc.gov/reading-rm/doccollections/nuregs/contract/cr6871/ cr6871.pdf and can be read with Adobe Acrobat Reader software, available at no cost from https://www.adobe.com. The report and the computer files for the test cases discussed therein are available at https://wwwrcamnl.wr.usgs.gov/rtm. Hard and electronic copies of the report are available from the contact listed below. FOR FURTHER INFORMATION CONTACT: Dr. John D. Randall, Mail Stop T9C34, U.S. Nuclear Regulatory Commission, 11545 Rockville Pike, Rockville, MD 20852, telephone (301) 415–6192, e-mail jdr@nrc.gov. 2. Strategic Planning. 3. Financial Update. 4. Personnel Matters and Compensation Issues. Dated at Rockville, Maryland, this 20th day of April 2005. For the Nuclear Regulatory Commission. Cheryl A. Trottier, Chief, Radiation Protection, Environmental Risk & Waste Management Branch, Division of Systems Analysis and Regulatory Effectiveness, Office of Nuclear Regulatory Research. [FR Doc. E5–2072 Filed 4–29–05; 8:45 am] AGENCY: BILLING CODE 7590–01–P POSTAL SERVICE United States Postal Service Board of Governors; Sunshine Act Meeting 1 p.m., Tuesday, May 10, 2005; and 8:30 a.m., Wednesday, May 11, 2005. PLACE: Atlanta, Georgia, at the Hyatt Regency Hotel, 265 Peachtree Street, NE., in the Hong Kong/Cairo Rooms. STATUS: May 10—1 p.m. (Closed); May 11—8:30 a.m. (Open). MATTERS TO BE CONSIDERED: TIMES AND DATES: Tuesday, May 10—1 p.m. (Closed) 1. Postal Rate Commission Opinion and Recommended Decision in Experimental Premium Forwarding Service, Docket No. MC2005–1. VerDate jul<14>2003 19:05 Apr 29, 2005 Jkt 205001 Wednesday, May 11—8:30 a.m. (Open) 1. Minutes of the Previous Meeting, April 12, 2005. 2. Remarks of the Postmaster General/ Chief Executive Officer. 3. Committee Reports and Audit and Finance Committee Charter. 4. Transformation. 5. Quarterly Report on Service Performance. 6. Quarterly Report on Financial Performance. 7. Atlanta District Report. 8. Tentative Agenda for the June 14, 2005, meeting in Washington, DC. CONTACT FOR FURTHER INFORMATION: William T. Johnstone, Secretary of the Board, U.S. Postal Service, 475 L’Enfant Plaza, SW., Washington, DC 20260– 1000. Telephone (202) 268–4800. William T. Johnstone, Secretary. [FR Doc. 05–8820 Filed 4–28–05; 2:35 pm] BILLING CODE 7710–12–M PRESIDIO TRUST Notice of Public Meeting ACTION: The Presidio Trust. Notice of public meeting. In accordance with § 103(c)(6) of the Presidio Trust Act, 16 U.S.C. § 460bb note, Title I of Public Law 104– 333, 110 Stat. 4097, as amended, and in accordance with the Presidio Trust’s bylaws, notice is hereby given that a public meeting of the Presidio Trust Board of Directors will be held commencing 5 p.m. on Wednesday, May 18, 2005, at the Officers’ Club, 50 Moraga Avenue, Presidio of San Francisco, California. The Presidio Trust was created by Congress in 1996 to manage approximately eighty percent of the former U.S. Army base known as the Presidio, in San Francisco, California. The purposes of this meeting are to provide an Executive Director’s Report, to provide project updates, and to receive public comment in accordance with the Trust’s Public Outreach Policy. Accommodation: Individuals requiring special accommodation at this meeting, such as needing a sign language interpreter, should contact Mollie Matull at (415) 561–5300 prior to May 9, 2005. FOR FURTHER INFORMATION CONTACT: Karen Cook, General Counsel, the Presidio Trust, 34 Graham Street, P.O. SUMMARY: PO 00000 Frm 00105 Fmt 4703 Sfmt 4703 22731 Box 29052, San Francisco, California 94129–0052, Telephone: (415) 561– 5300. Dated: April 25, 2005. Karen A. Cook, General Counsel. [FR Doc. 05–8652 Filed 4–29–05; 8:45 am] BILLING CODE 4310–4R–P SECURITIES AND EXCHANGE COMMISSION Proposed Collection; Comment Request Upon written request, copies available from: Securities and Exchange Commission, Office of Filings and Information Services, Washington, DC 20549. Extension: Regulation S–T, OMB Control No. 3235–0424, SEC File No. 270–375. Notice is hereby given that pursuant to the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.) the Securities and Exchange Commission (‘‘Commission’’) is soliciting comments on the collection of information summarized below. The Commission plans to submit this existing collection of information to the Office of Management and Budget for extension and approval. Regulation S–T (OMB Control No. 3235–0375; SEC File No. 270–424) sets forth the filing requirements relating to the submission of documents in electronic format on the Electronic Data Gathering Analysis and Retrieval (‘‘EDGAR’’) system. Regulation S–T is only assigned one burden hour for administrative convenience because it does not directly impose any information collection requirements. Written comments are invited on: (a) Whether the proposed collection of information is necessary for the proper performance of the functions of the agency, including whether the information will have practical utility; (b) the accuracy of the agency’s estimate of the burden of the collection of information; (c) ways to enhance the quality, utility, and clarity of the information collected; and (d) ways to minimize the burden of the collection of information on respondents, including through the use of automated collection techniques or other forms of information technology. Consideration will be given to comments and suggestions submitted in writing within 60 days of this publication. Please direct your written comments to R. Corey Booth, Director/Chief Information Officer, Office of Information Technology, Securities and E:\FR\FM\02MYN1.SGM 02MYN1

Agencies

[Federal Register Volume 70, Number 83 (Monday, May 2, 2005)]
[Notices]
[Pages 22730-22731]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E5-2072]


-----------------------------------------------------------------------

NUCLEAR REGULATORY COMMISSION


Draft Report for Comment: ``Documentation and Applications of the 
Reactive Geochemical Transport Model RATEQ,'' NUREG/CR-6871

AGENCY: Nuclear Regulatory Commission.

ACTION: Notice of availability and request for comments.

-----------------------------------------------------------------------

    Background: The U.S. Nuclear Regulatory Commission (NRC) uses 
environmental models to evaluate the potential release of radionuclides 
from NRC-licensed sites. In doing so, the NRC recognizes that, at many 
sites, groundwater-related pathways could contribute significantly to 
the potential dose received by members of the public. Consequently, 
consistent with its mission to protect the health and safety of the 
public and the environment, the NRC uses contaminant transport models 
to predict the locations and concentrations of radionuclides in soil as 
a function of time. Through this notice, the NRC is seeking comment on 
documentation of a subsurface transport model developed for the NRC by 
the U.S. Geological Survey (USGS) for realistic transport modeling at 
sites with complex chemical environments.
    Because many radionuclides temporarily attach, or adsorb, to the 
surfaces of soil particles, their mobility is reduced compared to that 
of compounds that move with the groundwater without interacting with 
solid surfaces. As a result, most subsurface-transport models used by 
the NRC and its licensees estimate the effects of the anticipated 
interactions between radionuclides and solids in the ground. Toward 
that end, these subsurface-transport models use a ``distribution 
coefficient,'' which is assumed to be constant and reflects the 
proportion of radionuclide in the groundwater compared to the 
radionuclide associated with the solids in the ground. These 
distribution coefficients are widely used, and consequently, the 
relevant literature documents ranges of their values for various soil 
types and radionuclides. However, the documented ranges can be very 
large because the chemical reactions that cause radionuclides to attach 
to solids are very sensitive to water chemistry and soil mineralogy. As 
a result, uncertainties in the parameters used to characterize the 
adsorption of radionuclides in soils have been identified as a major 
source of uncertainty in decommissioning, uranium recovery, and 
radioactive waste disposal cases evaluated by the NRC.
    Surface-complexation and ion-exchange models offer a more realistic 
approach to considering soil-radionuclide interactions in performance-
assessment models. These models can also account for variable chemical 
environments that might affect such interactions. The subject report, 
prepared for the NRC by the USGS, describes the theory, implementation, 
and examples of use of the RATEQ computer code, which simulates 
radionuclide transport in soil and allows the use of surface-
complexation and ion-exchange models to calculate distribution 
coefficients based on actual site chemistry.
    The RATEQ code will help the NRC staff define realistic site-
specific ranges of the distribution coefficient values used to evaluate 
NRC-licensed sites. In site-remediation cases, such as restoration of 
the groundwater aquifer in and around uranium in-situ leach mining 
facilities, the RATEQ code can aid in the estimation of restoration 
costs by estimating the volume of treatment water needed to restore 
sites to acceptable environmental conditions.

[[Page 22731]]

    Solicitation of Comments: The NRC seeks comments on the report and 
is especially interested in comments on the value of the report to 
users who run the RATEQ code and are familiar with the types of complex 
chemical environments that complicate many remediation projects.
    Comment Period: The NRC will consider all written comments received 
before August 12, 2005. Comments received after August 12, 2005, will 
be considered if time permits. Comments should be addressed to the 
contact listed below.
    Availability: An electronic version of the report is available in 
Adobe Portable Document Format at https://www.nrc.gov/reading-rm/doc-
collections/nuregs/contract/cr6871/cr6871.pdf and can be read with 
Adobe Acrobat Reader software, available at no cost from https://
www.adobe.com. The report and the computer files for the test cases 
discussed therein are available at https://wwwrcamnl.wr.usgs.gov/rtm. 
Hard and electronic copies of the report are available from the contact 
listed below.

FOR FURTHER INFORMATION CONTACT: Dr. John D. Randall, Mail Stop T9C34, 
U.S. Nuclear Regulatory Commission, 11545 Rockville Pike, Rockville, MD 
20852, telephone (301) 415-6192, e-mail jdr@nrc.gov.

    Dated at Rockville, Maryland, this 20th day of April 2005.

    For the Nuclear Regulatory Commission.
Cheryl A. Trottier,
Chief, Radiation Protection, Environmental Risk & Waste Management 
Branch, Division of Systems Analysis and Regulatory Effectiveness, 
Office of Nuclear Regulatory Research.
[FR Doc. E5-2072 Filed 4-29-05; 8:45 am]
BILLING CODE 7590-01-P
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