[Federal Register Volume 70, Number 83 (Monday, May 2, 2005)]
[Notices]
[Pages 22729-22730]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E5-2071]


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NUCLEAR REGULATORY COMMISSION


Availability of Interagency Steering Committee on Radiation 
Standards' Reports on Radioactivity in Sewage Sludge and Ash

AGENCIES: U.S. Nuclear Regulatory Commission and U.S. Environmental 
Protection Agency.

ACTION: Announce the issuance of two final reports concerning 
radioactivity in sewage sludge and ash.

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SUMMARY: This Federal Register notice announces the availability of two 
final reports, prepared by the Sewage Sludge Subcommittee of the 
Interagency Steering Committee on Radiation Standards (ISCORS), 
addressing radioactivity in sewage sludge and ash at publicly owned 
treatment works (POTWs). The first report, ``ISCORS Assessment of 
Radioactivity in Sewage Sludge: Modeling to Assess Radiation Doses,'' 
assesses the potential levels of radiation doses to people from 
radioactivity in sewage sludge, by modeling the transport of 
radioactivity from sludge into the local environment. The report also 
provides a complete description and justification of the dose 
assessment methodology. The second report, ``ISCORS Assessment of 
Radioactivity in Sewage Sludge: Recommendations on Management of 
Radioactive Materials in Sewage Sludge and Ash at Publicly Owned 
Treatment Works,'' is written for POTW operators. This report is 
intended to (1) alert POTW operators and others to the possibility of 
radioactive materials concentrating in sewage sludge and incinerator 
ash, (2) inform operators how to determine if there are elevated levels 
of radioactivity in their sludge, and (3) assist POTW operators in 
identifying further actions that may be taken to reduce potential 
radiation exposures from sludge and ash.

SUPPLEMENTARY INFORMATION:

Background

    The purpose of ISCORS is to foster early resolution and 
coordination of regulatory issues associated with radiation standards. 
Agencies represented on ISCORS include the U.S. Nuclear Regulatory 
Commission (NRC), the U.S. Environmental Protection Agency (EPA), the 
U.S. Department of Energy, the U.S. Department of Defense, the U.S. 
Department of Transportation, the Occupational Safety and Health 
Administration of the U.S. Department of Labor, the U.S. Department of 
Health and Human Services, and the Department of Homeland Security. The 
Office of Science and Technology Policy, the Office of Management and 
Budget, and State representatives may be observers at meetings. The 
objectives of ISCORS are to: (1) Facilitate a consensus on allowable 
levels of radiation risk to the public and workers; (2) promote 
consistent and scientifically sound risk assessment and risk management 
approaches in setting and implementing standards for occupational and 
public protection from ionizing radiation; (3) promote completeness and 
coherence of Federal standards for radiation protection; and (4) 
identify interagency radiation protection issues and coordinate their 
resolution.
    Discussion: There have been a number of well-publicized cases of 
radionuclides discovered in sewage sludge and ash, and some of these 
have led to expensive cleanup projects. These incidents made clear the 
need for a comprehensive determination of the prevalence of 
radionuclides in sewage sludge and ash at POTWs around the country, and 
of the level of potential threat posed to human health and the 
environment by various levels of such materials.
    In response to this need, ISCORS formed a Sewage Sludge 
Subcommittee to coordinate, evaluate, and resolve issues regarding 
radioactive materials in sewage sludge and ash. To estimate the amounts 
of radionuclides that actually occur in sewage sludge and ash, the 
Subcommittee performed a survey of radioactivity in sludge and ash 
across the United States. The final report of the survey effort, 
``ISCORS Assessment of Radioactivity in Sewage Sludge: Radiological 
Survey Results and Analysis'' (ISCORS Technical Report 2003-02, NUREG-
1775, EPA 832-R-03-002, DOE/EH-0669), was issued in

[[Page 22730]]

November 2003 and is available on the ISCORS Web site at http://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: http://www.iscors.org. Hard copies may also be 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 
[email protected]; 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 
[email protected].

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 
[email protected]; 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 [email protected].

    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