[Federal Register Volume 70, Number 217 (Thursday, November 10, 2005)]
[Proposed Rules]
[Pages 68350-68368]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-22432]


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 Proposed Rules
                                                 Federal Register
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 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
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  Federal Register / Vol. 70, No. 217 / Thursday, November 10, 2005 / 
Proposed Rules  

[[Page 68350]]



NUCLEAR REGULATORY COMMISSION

10 CFR Part 20

[RIN 3150-AE90]


Disposal of Radioactive Material by Release Into Sanitary Sewer 
Systems; Withdrawal of Advance Notice of Proposed Rulemaking

AGENCY: Nuclear Regulatory Commission.

ACTION: Advance notice of proposed rulemaking: Withdrawal.

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

SUMMARY: The Nuclear Regulatory Commission (NRC) is withdrawing an 
advance notice of proposed rulemaking (ANPR) that presented possible 
changes to the regulations governing the release of radionuclides from 
licensed nuclear facilities into sanitary sewer systems. Changes were 
proposed to account for the potential for radionuclide concentration 
during some types of wastewater treatment processes. NRC is withdrawing 
this advance notice of proposed rulemaking because it has determined 
that there are no widespread public health and safety concerns due to 
potential radiation exposures associated with the handling, beneficial 
use, and disposal of sewage sludge containing radioactive materials. 
This notice of withdrawal acknowledges public comments sent in response 
to the ANPR.

FOR FURTHER INFORMATION CONTACT: A. Christianne Ridge, Office of 
Nuclear Material Safety and Safeguards, U.S. Nuclear Regulatory 
Commission, Washington, DC 20555-0001, telephone (301) 415-5673, e-mail 
[email protected].

SUPPLEMENTARY INFORMATION: On February 25, 1994 (59 FR 9146), NRC 
published an ANPR to seek information to determine whether an amendment 
to its regulations governing the release of radionuclides from licensed 
nuclear facilities into sanitary sewer systems was needed. NRC was 
considering revising the approach to limiting these releases because of 
the potential effects of newly-developed sewage treatment technologies 
on radionuclide reconcentration during wastewater treatment. The 
Commission requested advice and recommendations on several proposals 
and asked related questions regarding whether and in what way the 
regulations governing the release of radionuclides from licensed 
nuclear facilities into sanitary sewer systems should be changed. NRC 
received seventy-four comment letters in response to the ANPR. The 
comment period expired on May 26, 1994.
    Because there were concerns raised on the broader issue of long-
term effects of releases of radioactive materials into sanitary sewer 
systems, action on the ANPR was deferred until studies were conducted 
regarding potential radioactive contamination in sewage sludge. Since 
that time, NRC participated in the Interagency Steering Committee of 
Radiation Standards (ISCORS) and co-chaired, with the Environmental 
Protection Agency (EPA), the Sewage Sludge Subcommittee to facilitate a 
systematic and thorough study of the potential concerns related to 
radionuclides in sewage sludge and to obtain data to support a 
technical basis for a regulatory decision.

Regulatory Framework Relevant to the Release of Radioactive Material 
Into Sanitary Sewers

    NRC regulations governing the release of licensed material into 
sanitary sewer systems can be found in 10 CFR 20.2003. This regulation 
was published in the Federal Register (56 FR 23360; May 21, 1991) as 
part of an overall revision of NRC standards for protection against 
radiation. Licensees were required to implement this regulation by 
January 1, 1993. As part of the 1991 revision of 10 CFR Part 20 
regulations, NRC removed the broad provision that allowed the release 
of non-biological insoluble materials into sanitary sewers because of 
the potential for this material to reconcentrate in sewers, publicly 
owned treatment works (POTWs), and sewage sludge. The current NRC 
regulations require that any licensed material discharged into a 
sanitary sewer system must be readily soluble in water or be readily 
dispersible biological material. In addition, the concentration limits 
for radionuclides released into a sanitary sewer system, listed in 
Table 3 of the Appendix B to Part 20, were reduced by a factor of 10 as 
part of an overall reduction in effluent release limits. In addition to 
the limits in 10 CFR 20.2003, NRC recommends that licensees should 
maintain doses as low as is reasonably achievable (ALARA) by setting 
goals for effluent concentrations and quantities to be only a modest 
fraction (10 to 20 percent) of their allowable limits, as described in 
NRC Regulatory Guide 8.37, ``ALARA Levels for Effluents from Materials 
Facilities,'' dated July 1993. NRC also conducts periodic inspections 
to ensure that licensees are in compliance with NRC regulations.

Surveys, Studies, and Reports Relevant to the Release of Radioactive 
Material Into Sanitary Sewers

    In May 1992, NRC issued the results of a scoping study in NUREG/CR-
5814, ``Evaluation of Exposure Pathways to Man from Disposal of 
Radioactive Materials into Sanitary Sewer Systems,'' which evaluated 
the potential radiological doses to POTW workers and members of the 
public from exposure to radionuclides in sewage sludge. The first part 
of the analysis estimated the potential doses to workers for five cases 
in which radioactive materials were detected at POTWs (Tonawanda, NY; 
Grand Island, NY; Royersford, PA; Oak Ridge, TN; and Washington, DC). 
Doses from the case studies were estimated to range from less than 10 
microsieverts per year ([mu]Sv/yr) (1 millirem per year (mrem/yr)) to 
930 [mu]Sv/yr (93 mrem/yr) for members of the public, using a 
deterministic scenario analysis and the reported radionuclide 
concentrations and/or discharges. The second part of the study 
estimated the maximum radiation exposures to POTW workers and others 
who could be affected by low levels of man-made radioactivity in 
wastewater. The quantities of radionuclides released into the sewer 
systems were assumed to be the maximum allowed under NRC regulations at 
the time. Estimates of the hypothetical, maximum exposures to workers 
ranged from zero to a dose roughly equal to the dose individuals 
receive from natural background radiation.
    In May 1994, the U.S. General Accounting Office (GAO, now U.S. 
Government Accountability Office) issued a report, GAO/RCED-94-133,

[[Page 68351]]

``Nuclear Regulation: Action Needed to Control Radioactive 
Contamination at Sewage Treatment Plants'', that described nine cases 
where contamination was found in sewage sludge or ash or in wastewater 
collection systems. GAO concluded that the full extent of contamination 
nationwide was unknown. GAO also concluded that the ``problem of 
radioactive contamination of sludge and ash in the reported cases was 
the result, in large part, of NRC's regulation, which was incorrectly 
based on the assumption that radioactive materials would flow through 
treatment systems and not concentrate.'' In June 1994, a joint U.S. 
House of Representatives and Senate hearing (June 21, 1994; S. Hrg. 
103-1034) was held to officially release and address questions raised 
in the GAO report. At the hearing, NRC and EPA agreed to cooperate to 
develop guidance for POTWs and to collect more data on the 
concentration of radioactive materials in samples of sewage sludge and 
ash from POTWs nationwide.
    Between 1994 and 1997, Federal, State, and industry studies were 
conducted to assess reconcentration of radioactive materials that are 
released into sanitary sewer systems. In December 1994, NRC published 
NUREG/CR-6289, ``Reconcentration of Radioactive Material Released into 
Sanitary Sewers in Accordance with 10 CFR Part 20.'' A review of the 
literature demonstrated that some radioactive materials discharged into 
sanitary sewer systems reconcentrate in sewage sludge. However, the 
report concluded that the available data were not sufficient to assess 
the adequacy of the requirements in 10 CFR 20.2003 in preventing 
occurrences of radionuclide reconcentration in sewage sludge at levels 
which present significant risk to the public; nor is the available data 
sufficient to suggest strategies for changing the requirements.
    In 1996, the Association of Metropolitan Sewerage Agencies (AMSA) 
conducted a limited survey of reconcentration of radioactivity in 
sewage sludge and ash samples from some of its member POTWs. Samples 
were obtained from 55 wastewater treatment plants in 17 States. The 
most significant sources of radioactivity were potassium and radium 
isotopes, which are Naturally Occurring Radioactive Materials (NORM). 
In December 1997, the Washington State Department of Health issued a 
report WDOH/320-013, ``The Presence of Radionuclides in Sewage Sludge 
and Their Effect on Human Health,'' that was based on sludge samples 
taken at six POTWs in the State. The report concluded that that there 
was no indication that radioactive material in sewage sludge in the 
State of Washington poses a health risk.
    The Interagency Steering Committee on Radiation Standards (ISCORS) 
was formed in 1995, to address inconsistencies, gaps, and overlaps in 
current radiation protection standards. In 1996, the Sewage Sludge 
Subcommittee of ISCORS was formed to coordinate efforts to address the 
recommendations in the 1994 GAO Report. Between 1998 and 2000, the EPA 
and NRC (through the ISCORS) jointly conducted a voluntary survey of 
POTW sewage sludge and ash to help assess the potential need for NRC 
and/or EPA regulatory decisions. Sludge and ash samples were analyzed 
from 313 POTWs, some of which had greater potential to receive releases 
of radionuclides from NRC and Agreement State licensees, and some of 
which were located in areas of the country with higher concentrations 
of NORM. In November 2003, the results of the survey were published in 
a final report, NUREG-1775, ``ISCORS Assessment of Radioactivity in 
Sewage Sludge: Radiological Survey Results and Analysis.'' No 
widespread or nationwide public health concern was identified by the 
survey and no excessive concentrations of radioactivity were observed 
in sludge or ash. The results indicated that the majority of samples 
with elevated radioactivity had elevated concentrations of NORM, such 
as radium, and did not have elevated concentrations of radionuclides 
from manmade sources.
    In February, 2005, the Sewage Sludge Subcommittee published a 
report, NUREG-1783, ``ISCORS Assessment of Radioactivity in Sewage 
Sludge: Modeling to Assess Radiation Doses.'' This report contains dose 
modeling results for seven different sewage sludge management scenarios 
for POTW workers and members of the public. Results of the dose models 
and survey results indicated that there is no widespread concern to 
public health and safety from potential radiation exposures associated 
with the handling, beneficial use, and disposal of sewage sludge 
containing radioactive materials, including NORM.
    In February, 2005, the Sewage Sludge Subcommittee also published a 
report, ``ISCORS Assessment of Radioactivity in Sewage Sludge: 
Recommendations on Management of Radioactive Materials in Sewage Sludge 
and Ash at Publicly Owned Treatment Works;'' (EPA 832-R-03-002B; ISCORS 
Technical Report 2004-04). This report provides guidance to: (1) Alert 
POTW operators, as well as State and Federal regulators, to the 
possibility that radioactive materials may concentrate in sewage sludge 
and incinerator ash; (2) inform POTW operators how to determine whether 
there are elevated levels of radioactive materials in the POTW's sludge 
or ash; and (3) assist POTW operators in identifying actions for 
reducing potential radiation exposure from sewage and ash.

Reasons for Withdrawing the ANPR

    The results of the survey and dose modeling work conducted by the 
ISCORS Sewage Sludge Subcommittee regarding radioactive materials in 
sewage sludge and ash provide a technical basis for withdrawing the 
ANPR. The survey demonstrated that the most significant levels of 
radioactive materials in POTWs are attributable to NORM. The dose 
modeling work indicated that, in general, the doses from licensed 
materials in sewage sludge present a sufficiently low health and safety 
risk to POTW workers and to the public under the current regulatory 
structure. Therefore, it is not necessary to modify the current 
restrictions regarding the release of radioactive materials into 
sanitary sewers (10 CFR 20.2003) as discussed in the ANPR. In addition, 
public comments indicated that several of the options discussed in the 
ANPR would be costly to implement and may not be consistent with 
efforts to maintain doses ALARA. For these reasons, NRC is withdrawing 
the ANPR.

Public Comments on the Potential Changes to 10 CFR Part 20

    In the ANPR, NRC invited comment on the following aspects of the 
regulation of release of radionuclides into sanitary sewers: The form 
of materials suitable for disposal, the limits on the total 
radioactivity of materials that can be released by a licensee into 
sanitary sewers in a year, also called the ``total quantity limit,'' 
the types of limits applied, and the exemption for medical patient 
excreta. The following is a summary of those comments and NRC 
responses.

(1) Form of Material for Disposal

    The May 21, 1991, final rule (10 CFR 20.2003) allows soluble and 
readily dispersible biological material to be released but prohibits 
the release of any non-biological insoluble material. Because NRC 
recognized that new technologies for wastewater treatment, such as ion-
exchange and some types of biological treatment, can reconcentrate 
radionuclides, NRC invited comments regarding whether and how 
regulations should account for the effects of different wastewater 
treatment

[[Page 68352]]

technologies on radionuclide reconcentration. NRC also invited comments 
regarding the potential impacts that additional restrictions on the 
form of materials allowable for release into sanitary sewers would have 
on licensee operations. Public comments regarding the adequacy of the 
current restrictions also were received.
    Comment: Nine commenters, including representatives of the New York 
State Energy Office, New York State Department of Environmental 
Conservation, AMSA, and the Department of Energy (DOE), expressed the 
view that the regulations should be reevaluated because of new sewage 
treatment technologies or should account for the effects of new 
technologies used to treat sewage or sewage sludge. One commenter 
suggested that NRC limits should account for a variety of POTW-specific 
factors, including sludge handling processes, and sludge disposal 
methods, and restrictions on the POTW's treated water discharge. 
Another commenter suggested NRC should take new sewage treatment 
technologies into account only if the results of NUREG/CR-6289, which 
was incomplete at the time the comment was made, indicated that new 
sewage treatment technologies had the potential to cause significant 
reconcentration of radionuclides in sewage sludge. Two commenters 
recommended NRC develop technology-specific reconcentration factors to 
help POTW operators to design appropriate pretreatment plans. A 
representative of DOE suggested NRC should expect that advances in the 
sewage treatment process would result in increasing concentration of 
radionuclides in sewage sludge. Two commenters recommended NRC 
regulations account for synergistic health effects of radiation and 
pollutants in wastewater, and one suggested NRC evaluate the 
synergistic effects of radiation and the chlorine and fluoride used in 
drinking water treatment.
    Response: NRC acknowledges the commenters' support for regulations 
that would account for the reconcentration of radionuclides by 
wastewater treatment processes. However, the regulations will not be 
changed because the ANPR is being withdrawn for the reasons previously 
explained.
    Comment: Four commenters expressed the view that NRC regulations 
should not take sewage treatment technologies into account. Reasons 
included uncertainty that new technologies will be implemented and a 
lack of information about the effects of the new technologies on 
radionuclide reconcentration. A representative of the State of Illinois 
Department of Nuclear Safety suggested NRC should keep informed of 
technological developments, but should not implement additional 
restrictions without significant evidence that the current restrictions 
are not adequate. Two commenters suggested that, rather than revising 
Sec.  20.2003 to account for new treatment technologies, NRC should 
consider placing additional restrictions on individual licensees to 
provide the necessary protection to the receiving POTWs in unusual 
cases where the number of licensees, size of the sewage treatment plant 
or nature of the technology used at the treatment plant may cause doses 
above 100 mrem/yr. One commenter stated that it is unnecessary for NRC 
regulations to account for sewage sludge treatment technologies because 
local POTWs have the authority and mandate to account for these 
technologies by developing industrial water discharge permits pursuant 
to 40 CFR 403.5(c)(1).
    Response: NRC acknowledges the commenters' opposition to the 
proposed rule change, which supports NRC's decision to withdraw the 
ANPR. With respect to the comment that POTWs have the authority and 
mandate to impose limits on radioactive materials released into 
sanitary sewers, NRC notes that, as described in Section 4.7 of the 
ISCORS recommendations on management of radioactive materials in sewage 
sludge and ash (EPA 832-R-03-002B), POTWs may not have the same 
authority to regulate radioactive material as they do to regulate other 
materials released into sanitary sewers.
    Comment: Eight commenters expressed the view that NRC regulations 
should account for the fact that several licensees may discharge to the 
same POTW, and, of those, five expressed the view that the regulations 
should also take the capacity of the POTW into account. Five commenters 
stated that restrictions on the release of nonradioactive pollutants 
established under EPA's National Pollutant Discharge Elimination System 
(NPDES) account for the capacity of the receiving POTW, the wastewater 
treatment systems used, and the number of industrial users discharging 
to a POTW, and suggested any new regulations governing the release of 
radioactive materials into sanitary sewers should take these factors 
into account. A representative of DOE expressed the view that changes 
to the regulations to account for multiple dischargers should be 
considered but may not be necessary because sanitary systems serving 
multiple licensees would probably be large systems in which the 
licensees' effluent would be diluted by many other inputs to the sewer 
system. One commenter suggested that, if limits on the total amount of 
radioactivity individual POTWs could receive were developed, any cases 
in which the limits are being exceeded by licensees that were already 
discharging sewage into the sewer system before the limits were 
developed should be handled on a case-by-case basis.
    Response: NRC acknowledges the commenters' support for regulations 
that would account for the capacity of individual POTWs and the number 
of licensees discharging to a single POTW. However, the proposed change 
will not be implemented for the reasons previously explained.
    Comment: Twenty-seven commenters were opposed to additional 
restrictions on the forms of material suitable for release into 
sanitary sewers. Twenty-one stated that the potential for significant 
reconcentration of radionuclides during wastewater treatment probably 
had been addressed by the May 21, 1991 changes to Part 20 (56 FR 23360) 
that restricted the forms of materials that could be released into 
sanitary sewers and lowered concentration limits. Another commenter 
expressed the view that it was unclear whether contamination described 
in the case studies discussed in the ANPR occurred because of 
violations of the existing regulations, and also that it would be 
inappropriate for NRC to respond to individual violations of regulatory 
requirements by making changes to the regulations for all licensees. 
Representatives of six licensees indicated that additional restrictions 
on the forms of material appropriate for disposal would impose a 
significant burden on their operations. Commenters listed the costs of 
building new storage facilities, analyzing samples of waste to 
determine whether insoluble radionuclides were present, and 
establishing new collection, handling, and disposal procedures as well 
as retraining of personnel as expenses that would be incurred if 
additional restrictions were imposed. In addition, three commenters 
expressed the concern that further restricting the forms of material 
appropriate for disposal in a sanitary sewer would not be consistent 
with NRC's policy that doses should be maintained ALARA because the 
additional waste handling that would be required would cause doses to 
workers that would not be justified based on the minimal dose to 
members of the public or POTW workers that might be avoided.
    Response: NRC acknowledges the commenters' remarks, which support

[[Page 68353]]

the withdrawal of the ANPR. However, the NRC staff notes the need to 
analyze samples of waste to determine if the waste contains insoluble 
radionuclides should not impose an additional burden because the 
restriction on releasing insoluble, non-biological wastes was already 
in place when the comment was made.
    Comment: Twenty-three commenters encouraged NRC to continue to 
allow release of readily soluble wastes that met the quantity and 
concentration release criteria in 10 CFR Part 20. Twenty-one of those 
commenters indicated that they were unaware of any significant problems 
caused by the disposal of soluble radioactive material in sewer 
systems. Three commenters stated that they were not aware of any 
mechanisms that would reconcentrate the wastes typical of biomedical 
research in sewage sludge, and two of these stated that the activity 
levels were sufficiently low that reconcentration, even if it did 
occur, would not cause a significant dose.
    Response: NRC acknowledges the commenters' support for the 
continuation of the current regulations which allow certain 
concentration and quantities of readily soluble radioactive material 
into sanitary sewers.
    Comment: Two commenters suggested that NRC should change the 
regulation to re-establish disposal of dispersible non-biological 
materials. One commenter suggested disposal of non-biological 
dispersible materials should be allowed for materials that have half-
lives of less than 100 days or are below the concentrations listed in 
10 CFR Part 20 Appendix C.
    Response: NRC acknowledges the commenters' suggestion that release 
of non-biological dispersible material into sanitary sewers be allowed. 
NRC understands that reconcentration of a radionuclide in sewage sludge 
can be limited by its half life. However, NRC has chosen not to change 
the regulation governing the release of radioactive material into 
sanitary sewers for the reasons previously explained.
    Comment: Six commenters, including a representative of DOE, noted 
that the chemical form of materials released into the sewer can change, 
and that materials that are soluble when released may precipitate or 
sorb to solid particles in the sewer or treatment plant. A 
representative of the New York State Department of Environmental 
Conservation suggested NRC study not only the effect of new 
technologies on radionuclide solubilities, but also how the solubility 
of radioactive materials change in sanitary sewers. A representative of 
DOE noted that precipitation and sorption could cause risks to 
individuals who work in POTWs, work in close contact with sewers, or 
who incinerate or use wastewater treatment sludge. In addition, the 
commenter remarked that, while it appeared to be reasonable to limit 
sewer releases to soluble and dispersible biological materials, NRC 
should realize that licensees could release insoluble or nondispersible 
materials to sewer systems inadvertently. One commenter expressed the 
view that NRC regulations should account not only for the form of 
material when released, but the form it was likely to take after being 
discharged.
    Three commenters expressed the view that, because the form of a 
material discharged is likely to change when it reaches the sewer or 
POTW, the modification to 10 CFR 20 that eliminated disposal for non-
biological ``readily-dispersible'' materials may not have removed the 
chance that radionuclides could reconcentrate in wastewater treatment 
sludge. Two commenters remarked that reconcentration of radionuclides 
probably would continue, in part because POTWs are designed to remove 
dissolved contaminants from wastewater. However, both commenters 
expressed the opinion that reconcentration is not necessarily a problem 
if the dose any individual is expected to receive from exposure to 
sewers, sewage, or sludge is low.
    Response: NRC understands that materials that are released into the 
sewer in a soluble form can precipitate or sorb to solid materials in 
sewers or POTWs, as discussed in NUREG/CR-6289. Most of the commenters' 
concerns about the potential risk to POTW workers are addressed in the 
ISCORS dose modeling report (NUREG-1783), as previously explained. 
Although the ISCORS dose analysis (NUREG-1783) does not include an 
analysis of doses to workers that come into contact with sewers, those 
doses are expected to be limited because of the limited amount of time 
a worker would spend in close contact with a sewer and because of the 
relatively low doses predicted for most scenarios that involve contact 
with sewage sludge.
    NRC acknowledges the concern that licensees may inadvertently 
dispose of insoluble non-biological material. NRC also acknowledges the 
suggestion that the regulations should account for changes in the form 
of materials that are likely to occur in sewers and POTWs and the 
concern about the efficacy of the 1991 revisions. For the reasons 
previously explained, NRC has decided not to change the regulations 
governing the release of radioactive material into sanitary sewers. 
However, NRC staff notes that, in addition to restrictions on form, NRC 
also has imposed annual limits in 10 CFR 20.2003(a)(4) on the total 
amount of radioactivity that can be released into sanitary sewers to 
limit the potential for reconcentration of radioactive material in 
sanitary sewers, sewage sludge, and sludge ash.
    Comment: Five commenters supported additional restrictions on the 
form of materials that can be released into sanitary sewers. One 
commenter expressed the view that the practice, used by some medical 
research laboratories, of releasing pureed tissue samples to the 
sanitary sewer was distasteful. Another commenter expressed the opinion 
that NRC should impose any requirement that would minimize the amount 
of radioactivity in the environment.
    Response: NRC acknowledges the commenters' support for additional 
restrictions on the forms of material suitable for release into 
sanitary sewers but is not changing the regulations because it believes 
the current approach is sufficiently protective, as previously 
explained.
    Comment: Three commenters requested clarification regarding the 
distinction between soluble and readily dispersible materials. One 
requested that an information notice be produced to address materials 
used in the biotech industry. Another commenter expressed the concern 
that it would be difficult to demonstrate compliance with the 
restriction that only soluble and readily-dispersible biological 
materials be released into sanitary sewers if colloids that flow 
through filters and resins are classified as non-biological dispersible 
material. The commenter proposed an operational procedure to 
distinguish between soluble and readily dispersible materials. A 
representative of the New York State Department of Environmental 
Conservation noted that traces of insoluble radioactive material could 
be released into sewers with soluble materials, and requested that NRC 
establish a lower limit of detection for insoluble material.
    Response: NRC acknowledges the commenters' request for additional 
guidance on how licensees should demonstrate the solubility of 
radioactive material released to sanitary sewers. Although NRC does not 
have plans to provide additional guidance on this issue, the staff 
notes that, as discussed in NRC Information Notice 94-007, licensees 
are free to develop alternative methods of demonstrating the solubility 
of materials they wish to release into sanitary sewers and to submit 
these

[[Page 68354]]

procedures to NRC for evaluation on a case-by-case basis.

(2) Total Quantity of Material

    In the May 21, 1991 final rule, NRC did not change the total 
quantity limits, which allow a licensee to release 185 gigabecquerel 
(GBq) (5 curies (Ci)) of H-3, 37 GBq (1 Ci) of C-14, and 37 GBq (1Ci) 
of all other radioactive materials combined into sanitary sewers each 
year. The use of total quantity limits has been a long-standing 
requirement and was originally included in the rule (10 CFR 
20.2003(a)(4)) to address concerns regarding the possibility for 
reconcentration of radionuclides. In the ANPR, NRC invited comments 
about the alternative approach of limiting the annual release of each 
radionuclide individually. NRC also invited comments about the current 
total quantity limits and the potential impacts that additional 
restrictions on the annual releases into sanitary sewers would have on 
licensees.
    Prior to publishing the ANPR, NRC received a petition for 
rulemaking to amend 10 CFR 20.303 (superseded by Sec.  20.2003) and 
Sec.  20.305 (superseded by Sec.  20.2004) from the Northeast Ohio 
Regional Sewer District (PRM-20-22). A notice of receipt of the 
petition was published in the Federal Register (58 FR 54071; October 
20, 1993). The petitioner requested that NRC amend its regulations to 
require that all licensees provide at least 24 hours advance notice to 
the appropriate POTW before releasing radioactive material to the 
sanitary sewer system. The petitioner also requested that NRC exempt 
materials that enter the sanitary waste stream from the requirements 
regarding Commission approval for incineration under NRC's current 
regulations. NRC solicited comments on the petition in the ANPR. The 
denial of the petition was noticed in the Federal Register on January 
27, 2005 (70 FR 3898).
    Comment: Six comments received in response to the ANPR supported 
annual total quantity limits. Two commenters, including a 
representative of DOE, suggested total quantity limits should be 
retained because they help prevent reconcentration of radionuclides in 
sewage sludge and two supported the total quantity limits because they 
are easy for licensees and regulators to understand and implement. Two 
commenters, including the representative of DOE, suggested it may be 
worthwhile for NRC to evaluate whether the regulation could be 
optimized by changing the annual release limits for some radionuclides. 
A representative of the Illinois Department of Nuclear Safety expressed 
the opinion that the relatively low doses calculated for the case 
studies described in the ANPR and predicted for other scenarios in 
NUREG/CR-5814 indicated that reconcentration of radionuclides in sewage 
sludge could be addressed on a case-by-case basis rather than by 
changing the total quantity limits in Sec.  20.2003.
    Response: NRC acknowledges support for the current approach of 
using annual limits on the total quantity of radioactive material that 
can be released into sanitary sewers by a licensee. In accord with the 
commenters' suggestion, NRC performed a study to evaluate the 
reconcentration of various radiounuclides in POTWs, the results of 
which are discussed in NUREG/CR-6289.
    Comment: A representative of the City of Oak Ridge made positive 
and negative statements about NRC annual total quantity limits. The 
commenter stated that both concentration and total quantity limits were 
necessary to ensure protection of workers and to ensure that 
traditional methods of sludge disposal remain acceptable. However, the 
commenter also expressed the view that the current values of the total 
quantity limits are too high and stated that disposal of 37 GBq (1 Ci) 
of Co-60 annually to the Oak Ridge POTW would result in unacceptably 
high concentrations of Co-60 in the POTW's sludge, especially if the 
material was released during a relatively short time period. The 
commenter also expressed the opinion that the total quantity limits are 
inappropriate for low specific activity radionuclides because of the 
large mass of the radionuclide that could be discharged. As an example, 
the commenter stated that release of 37 GBq (1 Ci) of U-238 to the 
city's POTW in a year would result in a mass concentration of uranium 
of more than 0.05 percent in the POTW's sludge, making the sludge 
licensable source material. In addition to these comments, the 
commenter suggested that, because the mean retention time of sludge at 
a POTW typically is one month or less, a monthly discharge limit would 
be more appropriate than an annual limit.
    Response: NRC acknowledges the commenter's concern about the 
release of Co-60 to a POTW and the suggestion that quantity limits 
should be implemented on a monthly, rather than an annual, basis. The 
staff notes that the 1991 revision to 10 CFR Part 20 that eliminated 
the discharge of insoluble non-dispersible radioactive material into 
sanitary sewers was implemented to reduce the possibility of 
significant contamination of sewage sludge with insoluble 
radionuclides, such as Co-60. NRC has decided not to change the 
regulations governing sewer release of radioactive material for the 
reasons previously explained. NRC acknowledges the commenter's concern 
about the applicability of the total quantity limit to low specific 
activity radionuclides. However, NRC does not agree that the 
accumulation of large masses of low-specific activity radionuclides in 
POTWs is likely to be problematic. In addition POTWs have some 
authority to impose limits on the release of material into sanitary 
sewers when the purpose of the limits is not radiation protection, as 
discussed in Section 4.7 of the ISCORS recommendations on management of 
radioactive materials in sewage sludge and ash (EPA 832-R-03-002B).
    Comment: Twenty-three commenters described concerns about the 
current approach of limiting the total amount of radioactivity a 
licensee may release into a sanitary sewer system. Nineteen commenters 
expressed the opinion that it is not appropriate to apply the same 
total quantity limit to large and small facilities that discharge 
different amounts of sewage and therefore dilute radioactive materials 
to different extents. Another commenter stated that NRC should not 
attempt to impose total quantity limits on large facilities. Seventeen 
commenters expressed the view that NRC should consider relaxing the 
total quantity limits because of the new restriction on the form of 
material and lower release concentration limits implemented in the 1991 
revision to 10 CFR Part 20. The commenters expressed the opinion that 
adherence to the new form and concentration limits may eliminate the 
need for total quantity limits. Three commenters suggested that, 
instead of limiting the total quantity of radioactivity a licensee 
could dispose of into a sewer, NRC should focus on the radionuclides 
and chemical forms of radionuclides that reconcentrate in POTWs to a 
significant extent. One commenter expressed the concern that a person 
could dispose of 37 GBq (1 Ci) of Cs-137 within a month while remaining 
in compliance with the current concentration and total quantity limits. 
Another commenter suggested concentration limits are sufficient and are 
superior to total quantity limits because concentration limits account 
for the total volume of water a licensee releases to the sanitary sewer 
system. The commenter noted that, although the nominal purpose of the 
total quantity limits is to eliminate reconcentration, the total 
quantity limits do not appear to prevent reconcentration, as evidenced 
by the case studies described in the

[[Page 68355]]

ANPR. The commenter suggested reconcentration could be avoided by 
reducing the allowable concentrations of those radionuclides that have 
shown a tendency to reconcentrate in sewage sludge.
    Response: NRC acknowledges the comment about the application of the 
same total quantity limit to large and small facilities, but believes 
that the system is appropriate. Because the total quantity limit is 
designed to reduce the potential for reconcentration of radionuclides 
at POTWs, an appropriate total quantity limit is more dependent on the 
volume of sewage received by a POTW than it is on the volume of a 
licensee's effluent.
    NRC acknowledges the comment that total quantity limits should be 
relaxed or eliminated, but does not agree that the limits on form and 
concentration eliminate the need for annual quantity limits. As 
discussed in NUREG/CR-6289, the form of radionuclides can change upon 
entering a sewer or POTW because of sorption and precipitation. NRC 
also acknowledges the concern that total quantity limits did not 
prevent the cases of contamination discussed in the ANPR. NRC believes 
that limiting both the form and total quantity of material released 
into sanitary sewers is the best way to limit the potential for 
significant reconcentration of radionuclides released by licensees into 
sanitary sewers.
    NRC acknowledges the commenters' suggestion that, instead of 
imposing total quantity limits, it should focus on those radionuclides 
that have been shown to reconcentrate in sewers or sewage sludge. NRC 
also acknowledges the commenter's concern about the discharge of Cs-137 
but believes the current approach to be sufficiently protective for the 
reasons previously explained.
    Comment: One commenter expressed the view that additional 
limitations on the release of H-3 and C-14 into sanitary sewers would 
not produce any public health benefit because any dose an individual 
received from sewer-disposed H-3 and C-14 would be negligible in 
comparison to the dose the individual would receive from naturally-
produced H-3 and C-14.
    Response: NRC acknowledges the commenter's view that additional 
restrictions on the quantities of H-3 and C-14 are unnecessary. The 
comment supports the withdrawal of the ANPR and the current total 
quantity limits which allow the annual release of 185 GBq (5 Ci) of H-3 
and 37 GBq (1 Ci) of C-14 in addition to the release of 37 GBq (1 Ci) 
of all other radionuclides combined.
    Comment: Eight licensees expressed the view that additional 
restrictions on the total quantity of radioactive material that could 
be released into sanitary sewers annually would have a severe negative 
impact on their facilities' operations. Representatives of a biomedical 
company, a university, and the National Institutes of Health (NIH) 
noted that a reduction in the total quantity limits would impose a 
significant financial burden on organizations involved in biotechnical 
research, development, or medical practice, especially if the limits 
were reduced to a point that liquid wastes would need to be solidified 
and disposed of as low level waste (LLW). The representative of NIH 
estimated that solidification and disposal of liquid wastes as LLW 
would cost NIH 2.8 million dollars annually, as of 1994. Two commenters 
remarked that companies would bear the additional expense of acquiring 
or building storage facilities or acquiring treatment technologies to 
remove radioactivity from liquid waste streams. One commenter noted 
that LLW disposal of many of the materials currently released into 
sanitary sewer systems would be a particularly unnecessary expense and 
inefficient use of LLW landfill space because, in many cases, the 
material would decay to negligible quantities before it reached the LLW 
landfill.
    Five commenters associated with medical research facilities or 
companies that produce radiopharmaceuticals suggested additional 
restrictions on the total quantity of radioactive material that could 
be released into sanitary sewers annually could harm public health and 
safety by causing companies to limit biomedical research and 
development efforts. One of these commenters stated that the amount of 
radioactivity released into sanitary sewers in association with medical 
research was insignificant as compared to the amount of radioactivity 
released to sewers in patient excreta and concluded that release of 
radioactive materials associated with biomedical research should be 
allowed as long as the exemption for patient excreta is continued. Two 
commenters expressed the opinion that additional restrictions on the 
total quantity of radioactivity a licensee could release into sanitary 
sewers annually would not be consistent with efforts to maintain doses 
ALARA because workers would be exposed to radioactive material while 
processing liquid waste to make it suitable for LLW disposal.
    A representative of a company that offers health physics services 
stated that, for most of its clients who want to release radioactive 
material into sanitary sewers, the most limiting factor is the annual 
total quantity limits. A representative of the University of California 
expressed concern that the numerical limits in 10 CFR 20.2003 would be 
lowered, although the university typically releases only 11.1 Gbq (0.2 
Ci) of radioactivity into sanitary sewers each year.
    Response: NRC acknowledges the commenter's concerns about the 
potential impacts of additional restrictions on the total quantity of 
radioactive material that a licensee can release to sewers annually. As 
previously explained, the additional restrictions discussed in the ANPR 
will not be implemented.
    Comment: A representative of AMSA stated that, although the 
organization understands that lowering total quantity limits could 
impose financial burdens on licensees, additional restrictions are 
appropriate if they are needed to prevent contamination of sewage 
sludge.
    Response: NRC acknowledges the commenter's statement, but has 
decided not to change the total quantity limits because it believes the 
current approach is sufficiently protective for the reasons previously 
explained.
    Comment: Twenty-one letters received in response to the ANPR 
included comments on the Northeast Ohio Regional Sewer District's 
request for NRC to amend its regulations to require that all licensees 
provide at least 24 hours advance notice to the appropriate POTW before 
releasing radioactive material into a sanitary sewer system. Six of the 
twenty-one commenters supported a requirement for licensees to provide 
the sewage treatment plant with some type of reporting on the 
radioactive materials released into the sanitary sewer system. These 
commenters supported a wide range of reporting requirements, including 
the petitioner's request for a 24-hour advance notification before 
licensees release radioactive material, monthly or annual discharge 
reports, reports of releases that could be a threat to the POTW workers 
or the environment, or notification of large accidental releases. One 
commenter suggested licensees should analyze effluent samples and 
include the results in discharge reports. A representative of AMSA 
stated that advance notice of releases is necessary so that POTW 
operators can ensure worker health and safety and make appropriate 
decisions about sludge disposal and reuse.
    Fifteen of the twenty-one commenters did not support such a 
requirement for licensees to provide at least 24-hour

[[Page 68356]]

advance notice to the appropriate sewage treatment plant before 
releasing radioactive material into a sanitary sewer system. Several 
commenters said that a 24-hour advance notification would result in an 
unnecessary regulatory burden without providing additional protection 
against radiation or dose reduction. These commenters expressed the 
view that the existing regulations for discharges of licensed material 
maintain doses at or below the existing dose limits for members of the 
public and if licensees meet the ALARA goals, the 24-hour advance 
notification would be unnecessary. Several commenters noted that such 
notification would be impractical because most releases are continuous 
and involve very small quantities of radioactive material. For example, 
discharges from hospitals and medical facilities would change daily 
depending on the number of patients treated and types of treatment 
used.
    Several commenters also noted that there could be large cost 
implications and regulatory burdens associated with such notification. 
In addition, commenters were concerned that data about releases of 
radioactive material could be misinterpreted if release reports were 
received and interpreted by sewage treatment plant personnel rather 
than radiation safety specialists. Several commenters stated that such 
an NRC requirement for licensees to provide a 24-hour advance 
notification was unnecessary because local municipalities have 
authority over their local sewer district, already have requirements to 
follow the Clean Water Act, and may establish a pretreatment program 
for wastewater acceptance. One commenter noted that the usefulness of a 
24-hour advance notification should be assessed after the new limits 
for sewer discharges are in place.
    Response: NRC has determined that a requirement for advance 
notification of each release of radioactive material to a sanitary 
sewer would impose an unnecessary regulatory burden on licensees 
without a commensurate health and safety benefit. Additional reasons 
for the denial of the petition are discussed in the Federal Register 
notice published on January 27, 2005 (70 FR 3898).
    Comment: Six comment letters received in response to the ANPR 
included comments on the Northeast Ohio Regional Sewer District's 
request that NRC exempt materials that enter the sanitary waste stream 
from the requirement for NRC approval prior to treatment or disposal of 
licensed material by incineration. Four commenters supported such an 
amendment because, given the radioisotopes and activities involved, the 
pathways for human exposure from radioactive wastes seem no more or 
less significant if the wastes are dispersed into water or air. These 
commenters suggested that, if release into a sanitary sewer system is 
to be considered disposal, the limits should be set so that no further 
regulation of the radioactive material is needed after release. One 
commenter did not support such an amendment and expressed the view that 
it would only serve to provide an open-ended system for radioactive 
material to pass into the environment and to the public without 
limitation or characterization.
    Response: NRC approval to incinerating waste is required to ensure 
that NRC may evaluate the potential impact to the public health and 
safety and the environment on a case-by-case and site-specific basis. 
Hazards associated with incineration of sewage sludge will depend on 
the specific characteristic of the sludge and the radionuclides that 
may be present. Additional reasons for the denial of the petition are 
discussed in the Federal Register notice published on January 27, 2005 
(70 FR 3898).

(3) Type of Limits

    The present approach to limiting releases of radioactive material 
into sanitary sewers is to specify limits on both the monthly average 
concentration of each radionuclide in a licensee's sewage and the total 
quantity of radioactive matter that a licensee can release annually. 
Table 3, Appendix B, of 10 CFR Part 20 lists the allowable monthly 
average concentration of each radionuclide in a licensee's release to 
sewers. Allowable concentrations are based upon a calculated dose of 5 
mSv/yr (500 mrem/yr) due to ingestion of 2 liters per day of a 
licensee's effluent into the sanitary sewer.
    In the ANPR, NRC invited comments on this regulatory approach. 
Specifically, NRC invited comment as to whether it should continue to 
base concentration limits on the assumption that an individual would 
drink 2 liters of the effluent from a licensee's facility each day, and 
whether exposure at other locations, such as at a POTW, should be 
considered in developing release limits. In addition, NRC invited 
comments about how other exposure scenarios, such as exposure to 
radionuclides in contaminated sludge, should be accounted for. NRC also 
invited comments as to whether it should establish limits in terms of 
dose instead of limits on the quantity and concentrations of 
radioactive material discharged. Included with the responses to these 
inquiries were several comments about monitoring, enforcement actions, 
and regulatory authority to set limits on releases of radioactive 
material into sanitary sewers that have been addressed with the General 
Comments.
    Comment: Twenty-three commenters supported the current modeling 
approach of assuming that an individual ingests 2 liters of water taken 
from the licensee's outfall to the sewer system each day. Nineteen of 
these commenters, representing hospitals, biomedical laboratories, and 
universities, noted that this assumption is conservative and easy for 
licensees to understand. A representative of DOE noted that the 
approach appears to be bounding, and has been ``largely successful as a 
regulatory measure''. The commenter also expressed the view that, 
because this type of consumption is not expected to be chronic, it is 
appropriate to base concentration limits on a calculated annual dose of 
500 mrem instead of 100 mrem. One commenter did not specifically 
address the assumption that an individual would drink 2 liters of a 
licensee's discharge each day, but did support the use of a licensee's 
sewer outfall as an appropriate exposure location. Two commenters 
expressed the view that the modeling assumption was appropriate because 
individuals, including children, could drink or otherwise be exposed to 
water directly downstream of a sewer outfall. Another commenter that 
supported the current assumption expressed the view that modeling 
exposure at a licensee's outfall to a sewer system is consistent with 
modeling exposure at a licensee's fence line, as is done in other NRC 
assessments, and that considering a downstream location would be 
inconsistent with modeling exposure to the maximally exposed 
individual.
    Response: NRC acknowledges support for the current modeling 
assumption. The staff notes that several commenters appeared to believe 
that the concentration limits were based on the assumption that an 
individual would consume 2 liters of sewage from a POTW outfall, rather 
than 2 liters of a licensee's effluent into the sewer system, each day. 
Staff notes that the assumption that an individual would consume a 
licensee's effluent is more conservative than the assumption that an 
individual would consume POTW effluent because the concentration of 
radionuclides in POTW effluent will have been diluted with effluent 
from all of the other residential and industrial dischargers to the 
POTW.

[[Page 68357]]

    Comment: Three commenters expressed concern that the concentration 
limits are based on an annual dose of 5 mSv (500 mrem) and stated that 
the concentration limits should be based on an annual dose of no more 
than 1 mSv (100 mrem), in accord with the 10 CFR 20.1301 limit on doses 
to members of the general public from licensed activities. One 
commenter expressed the view that the 1 mSv (100 mrem) annual public 
dose limit should be lowered. Two commenters expressed the view that 
the dose from ingesting a licensee's effluent should be included in the 
1 mSv (100 mrem) TEDE annual public dose limit rather than being 
calculated separately and excluded from the 10 CFR 20.1301 limit. 
Another expressed the view that, if any activity were to be permitted 
to be discharged into sanitary sewers, the limiting dose for exposure 
to sewage sludge should be no greater than the dose limit for low level 
radioactive waste.
    Response: NRC acknowledges the commenters' concern about the 
hypothetical dose used as the basis for the concentration limits. As 
discussed in the ANPR, the NRC staff believes the concentration limits 
based on an annual dose of 5 mSv (500 mrem) are reasonable because it 
is unlikely that an individual would have access to and would consume 
water at the point at which a licensee discharges water into the 
sanitary sewer and because dilution from additional discharges into the 
sewer is likely to reduce the expected dose to well below the 1 mSv 
(100 mrem) annual dose limit.
    NRC also acknowledges the commenters' suggestion that the dose from 
consuming effluent released into the sanitary sewer be included in the 
TEDE from other licensee operations. However, in the case of sewer 
discharge, the point of exposure is expected to be remote from the 
licensee's facility. Because individuals that could be exposed to a 
facility's effluent are different individuals than those that live 
closest to the facility, it would be unrealistic to include the dose 
from exposure to a licensed facility's effluent in the total dose from 
all of the facility's activities. The staff notes that comments 
regarding the appropriate value of the annual dose limit for members of 
the public from licensed activities specified in 10 CFR 20.1301 are 
beyond the scope of this rulemaking.
    Comment: Ten commenters did not support the use of the current 
modeling approach of assuming that an individual ingests 2 liters of 
water taken from a licensee's sewer outfall each day. Almost all of 
these commenters expressed the view that the assumption is unrealistic. 
One commenter expressed the view that, while the assumption that an 
individual ingests 2 liters of water taken from a licensee's sewer 
outfall each day is a reasonably conservative basis for concentration 
limits, the assumption may not be a basis for total quantity limits 
because it would over-emphasize the potential impact of short-lived 
radionuclides.
    Response: NRC acknowledges the commenters' opposition to the 
current modeling approach. However, it will be retained because the 
ANPR is being withdrawn for the reasons previously explained. With 
respect to the comment about the basis for total quantity limits, the 
staff notes that the assumption that an individual would consume a 
licensee's effluent is used as the basis of the concentration limits 
but is not used as the basis of the total quantity limits.
    Comment: Ten commenters suggested alternate locations that NRC 
should consider when developing restrictions on the release radioactive 
materials into sanitary sewer systems. Of these, five suggested NRC 
consider the dose to a person ingesting water once it has reached or is 
leaving a POTW rather than at the licensee's sewer outfall. Three 
commenters suggested NRC consider locations downstream of a POTW that 
would be likely to be locations from which a municipality would extract 
drinking water, while one suggested doses in the nearest residential 
area should be considered. Another commenter suggested realistic models 
would incorporate a factor of at least one million between the point of 
discharge and a receptor locations, and suggested that, if NRC used a 
more realistic dose model, it would become clear that additional 
release restrictions are unnecessary. One commenter suggested that, in 
considering potential doses to members of the public, NRC should 
consider that sludge could be sent to a landfill, applied to 
agricultural land, or made into compost for sale to the public.
    Five commenters, including representatives of POTWs and DOE, 
recommended NRC consider doses to sanitation workers and two commenters 
suggested NRC consider doses to workers that come into contact with 
sewage collection systems as well as POTW workers. One commenter noted 
the importance of matching exposure locations to appropriate pathways 
and suggested external radiation by gamma emitters may be an important 
pathway for POTW workers, whereas ingestion of beta emitters would be 
expected to be more important at a downstream drinking water source. 
Five commenters suggested NRC consider that the careful treatment given 
to sewage and sludge because of the other hazards it presents should 
limit doses to sanitary system workers. One commenter added that NRC 
regulations also should prevent contamination of sewers, POTWs, 
receiving waters, and sludge and ash disposal sites. Another commenter 
suggested NRC consider potential exposures to all POTW residuals, 
including sludge, screenings, grit, and ash. The commenter also pointed 
out that sewer pipes may leak and suggested NRC consider the potential 
for groundwater contamination.
    Response: The alternate locations that the commenters suggested 
should be considered in dose models will not be used as a basis for a 
revision to the regulations because the ANPR is being withdrawn for the 
reasons previously explained. However, the NRC staff notes that several 
of the modeling scenarios suggested by the commenters, including sludge 
handling by POTW workers, sludge incineration, and exposure to land-
applied sewage sludge, were considered in the ISCORS dose modeling 
project (NUREG-1783).
    Comment: Six commenters, including representatives of POTWs and the 
New York State Department of Environmental Conservation, suggested 
that, in addition to protecting the general public and sanitation 
workers, NRC regulations should ensure that POTWs can continue to use 
traditional forms of use or disposal of biosolids (sewage sludge). One 
commenter noted that events that have not resulted in significant 
worker exposure have prevented POTWs from using or disposing of sewage 
sludge.
    Response: Additional restrictions on the release of radioactive 
material into sanitary sewers will not be implemented for the reasons 
previously discussed. Section 7.2 of the ISCORS recommendations on 
management of radioactive materials in sewage sludge and ash (EPA 832-
R-03-002B) provides guidance to assist POTW operators in reducing 
sources of radiation entering their treatment facilities.
    Comment: Four commenters made suggestions about ways to account for 
complex exposure scenarios, such as exposure to contaminated sewage 
sludge. One commenter suggested that a variety of scenarios should be 
evaluated and that the scenario resulting in the highest dose should be 
used to establish limits on releases of radionuclides to sewers. 
Another commenter expressed the opinion that dose models should reflect 
limitations on access that are imposed to protect individuals from 
other health risks associated with sewage and sewage sludge. One

[[Page 68358]]

commenter suggested no model could adequately represent complex 
exposure scenarios because dose modeling was not sufficiently well 
developed.
    Response: The approaches the commenters suggested will not be used 
as a basis for new restrictions on the release of radioactive material 
into sanitary sewers because the ANPR is being withdrawn for the 
reasons previously explained. NRC staff acknowledge the commenter's 
statement about the capabilities of dose modeling.
    Comment: Of the fourteen commenters that addressed dose limits, 
seven supported implementation of dose limits. One commenter expressed 
the view that dose limits are preferable to limits on concentration and 
quantity alone because dose limits are easier to relate to risk. The 
commenter suggested the assumptions used to evaluate compliance with 
dose limits should be realistic. The commenter also suggested the use 
of a tiered approach, in which simple bounding assumptions are first 
used to evaluate compliance, and more complex models and more site-
specific data are used only if the simple bounding model does not 
demonstrate compliance. Another commenter suggested that, if the 
appropriate models were developed, releases into sanitary sewers should 
be controlled under the requirements of 10 CFR 20.1302 and ALARA 
guidelines just as other facility effluents are. The commenter also 
noted that the potential doses calculated in NUREG/CR-5814 indicate 
that the current regulations governing the release of radionuclides 
into sanitary sewers are more restrictive than other NRC dose limits on 
facility effluents. Two commenters expressed the view that dose limits 
should be adopted only if the current limits were found not to be 
protective of the public or POTW workers. Four commenters agreed with 
the proposal in the ANPR that, if dose limits were adopted, NRC should 
publish a regulatory guide that included concentration and total 
quantity guidelines to facilitate compliance. One commenter asked if 
licensees would have a choice of complying with the dose limit or with 
the concentration and quantity guidelines published in a Regulatory 
Guide. Two commenters advocated dose limits, but expressed the view 
that the dose limits should be based on measured radionuclide 
concentrations from samples taken from sewer outfalls and intakes or on 
readings from dosimeters placed at POTWs rather than on concentrations 
calculated based on assumptions about releases to and dilution in 
sanitary sewers.
    Response: NRC acknowledges the commenters' support for sewer 
release restrictions to be expressed as limits on dose rather than 
activity. NRC also acknowledges the commenters' suggestion that 
compliance with dose limits be made based on sample measurements. 
However, these options will not be implemented because the ANPR is 
being withdrawn for the reasons previously explained. No response is 
required to the commenter's question about compliance with dose limits 
because the ANPR is being withdrawn.
    Comment: Of the fourteen commenters that addressed dose limits, six 
commenters opposed dose limits, and a representative of the New York 
State Department of Environmental Conservation noted potential problems 
with implementing dose limits but suggested NRC study the option. 
Almost all of the commenters that opposed dose limits commented on the 
uncertainty of assumptions about exposure pathways and the relative 
complexity of implementing dose limits as compared to concentration and 
quantity limits. Three commenters predicted dose limits would require 
more regulatory oversight because NRC would need to review each 
licensee's dose model. One commenter expressed the concern that dose 
limits could make it necessary for licensees to require prior approval 
for releases of radioactive material into sanitary sewers. One 
commenter supported the current limits but suggested that, if dose 
limits were adopted, the dose limit should be 500 mrem/yr, realistic 
modeling assumptions should be made, and the modeling assumptions to be 
used in compliance calculations should be clearly defined. Another 
commenter advocated the use of limits expressed in ``verifiable units 
of measure'' rather than limits expressed as dose and expressed doubts 
about the capabilities of computer models used to calculate dose. 
Another commenter stated NRC should not limit the dose a patient could 
receive from a prescribed medical procedure.
    Response: NRC acknowledges the commenters' opposition to dose 
limits, which will not be implemented because the ANPR is being 
withdrawn.
    With respect to the commenter's concern that NRC should not limit 
the dose a patient could receive due to a medical procedure prescribed 
by his physician, the NRC staff notes the scope of the ANPR was limited 
to potential doses due to exposure to radioactive material in sewage or 
sludge. In general, NRC regulates the uses of radionuclides in medicine 
as necessary to provide for the radiation safety of workers and the 
general public and does not intrude into medical judgments affecting 
patients. Additional detail on this topic can be found in NRC's Final 
Policy Statement on the Medical Use of Byproduct Material, which was 
published in the Federal Register on August 3, 2000 (70 FR 3898).
    Comment: Two commenters expressed concern that NRC would consider 
setting any non-zero dose limit for POTW workers. Both commenters 
expressed the view that any dose received by a POTW worker because of 
exposure to radionuclides released into sanitary sewers by licensees 
would not be ALARA if the only reason such releases were allowed was to 
provide an inexpensive method of waste disposal to NRC licensees.
    Response: NRC acknowledges the commenters' concern about sanitary 
system worker doses but disagrees with the view that only a dose of 
zero could be ALARA. The staff notes that the ISCORS dose modeling 
report (NUREG-1783) concludes that POTW worker doses typically are very 
low and are dominated by exposure to NORM. Additional restrictions on 
the release of radioactive material into sanitary sewers will not be 
implemented for the reasons previously discussed.
    Comment: Three commenters expressed views on the appropriate time 
period over which releases should be averaged. A representative of a 
municipality suggested monthly averages should not be used because the 
practice encourages the use of dilution as a means of meeting the 
regulations. A representative of AMSA suggested daily averages should 
be used because POTW workers could be exposed to sewage and sludge on a 
daily basis. In contrast, a representative of a public utility district 
supported the use of weekly or monthly averages.
    Response: NRC acknowledges the commenters' suggestions about 
appropriate time periods over which releases should be averaged. NRC 
believes monthly averages are appropriate because the effects of small 
quantities of radioactivity released during a month are not expected to 
depend on the time period over which the radioactive material is 
discharged. Monthly limits will be retained because the ANPR is being 
withdrawn for the reasons previously explained.
    Comment: Ten commenters supported the development of annual release 
limits for individual radionuclides or groups of radionuclides. Eight 
commenters suggested limits for individual radionuclides should be 
based on the results of dose models. Specific factors that commenters

[[Page 68359]]

suggested should be included in a dose model included a radionuclide's 
specific activity, half-life, and solubility, and factors affecting the 
radionuclide's fate and transport in sewers, wastewater treatment 
process, and the environment. Two commenters recommended NRC consider 
imposing different discharge limits for those radionuclides and 
chemical forms that reconcentrate in POTWs to a significant extent and 
those that do not. Another commenter suggested NRC set limits for 
individual radionuclides based on whether they pose a risk primarily 
due to internal or external exposure and specifically suggested pathway 
modeling should include exposure to radionuclides that volatilize from 
sewage at a POTW, exposure to raw river water, and ingestion of treated 
river water. Another commenter suggested NRC consider the fate of 
radionuclides in engineered wetlands that are used by some POTWs as a 
final treatment step. One commenter predicted annual release limits for 
individual radionuclides would provide more flexibility to licensees 
and eliminate the need for special licensing exceptions to the current 
total quantity limits. A representative of DOE predicted that only a 
very few radionuclides would require reduced quantity limits even if 
the limits were conservative to bound variations in sewage plant 
designs and operating characteristics and to account for potential 
improvements in waste water treatment technology.
    Four commenters suggested that annual release limits should be 
based on radionuclide half-life. A representative of the Texas 
Department of Health predicted it may be difficult for licensees to 
keep track of the quantity of each radionuclide released and suggested 
NRC impose one quantity limit for short-lived radionuclides that would 
be unlikely to reconcentrate in sewage sludge and a lower limit for 
long-lived radionuclides that have a greater potential to reconcentrate 
in sewage sludge.
    A representative of the New York State Department of Environmental 
Conservation noted that it may not be appropriate to use Annual Limit 
of Intake (ALI) values as a basis for annual release limits for 
individual radionuclides, as suggested in the ANPR, because the 
ingestion pathway may not be the most significant exposure pathway and 
because the chemical form of a radionuclide may be significantly 
different when it is released from a POTW than it was when it was 
originally discharged to the sewer. One commenter suggested both the 
total quantity of all radionuclides as well as quantities of individual 
radionuclides released should be limited, and that quantity limits for 
individual radionuclides should be based on fractions, rather than 
multiples, of ALI values. The commenter also suggested annual limits 
should assure the lowest possible rather than the lowest ``reasonably 
achievable'' exposure of members of the public to radionuclides.
    Response: NRC acknowledges the commenters' support for the 
development of annual release limits for individual radionuclides or 
groups of radiounuclides. However, the proposed change will not be made 
because the ANPR is being withdrawn for the reasons previously 
explained.
    Comment: Five commenters opposed the development of annual release 
limits for individual radionuclides. Two commenters suggested the low 
calculated doses received in the case studies discussed in the ANPR 
indicate the current regulations are adequate. Two commenters suggested 
that, if NRC were to change the annual quantity limits, it should focus 
on Co-60, Sr-90, Cs-137, Ir-192, and Am-241, because these 
radionuclides were identified in NUREG/CR-5814 as having the potential 
to result in a significant dose, based on the pre-1991 release limits. 
A representative of the State of Illinois Department of Nuclear Safety 
recommended NRC change the total quantity limits only if the releases 
of Co-60, Sr-90, Cs-137, Ir-192, and Am-241 that were determined to be 
potentially problematic in NUREG/CR-5814 would still be permitted, 
given the restrictions on form and lower concentration limits 
introduced in the 1991 revision to 10 CFR part 20.
    Another commenter noted that, although limiting the quantities of 
radionuclides released would not necessarily be difficult, the need to 
analyze batches of wastewater to determine the quantities of individual 
radionuclides being released would be a significant burden as compared 
to the current method the company uses, which is to base releases on 
DOT shipping papers that identify the most limiting radionuclide in a 
batch. However, the commenter also noted that using limits based on 
multiples of ALI would be ``on the right track'' and would be similar 
to methods used in Europe.
    One commenter expressed the view that the biokinetics of individual 
radionuclides could not be modeled well enough to provide a basis for 
limits on the quantity, concentration, or form in which a radionuclide 
could be discharged, especially because the models would not include 
the synergistic effects of radiation and other pollutants. The 
commenter also expressed the view that the exempt quantities published 
in 10 CFR Part 30 represented quantities ``below regulatory concern'' 
(BRC) and suggested it would be inappropriate to use multiples of the 
exempt quantity values as annual quantity limits.
    Response: NRC acknowledges the commenters' opposition to annual 
release limits for individual radionuclides, which supports withdrawal 
of the ANPR.

(4) Exemption of Patient Excreta

    The fourth topic on which NRC invited comment was the exemption of 
patient excreta from the regulations governing releases of radioactive 
material into sanitary sewers. NRC received fifty-two letters that 
addressed the exemption for patient excreta.
    Comment: Forty-four commenters, including a representative of AMSA, 
recommended the exemption for patient excreta be continued and 
suggested it required no additional evaluation. Thirty-three of the 
commenters stated the exemption is necessary to maintain doses ALARA. 
Several commenters predicted that the radiological risks to health care 
workers, in the case of hospitalized patients, or family members, in 
the case of patients released from the hospital, associated with 
managing excreta would be far greater than any risk that the excreta 
would pose to POTW workers or members of the general public once 
released to the sewer system. Several commenters noted the possibility 
that excreta could be spilled or inadequately shielded, especially in 
the case of patients that had been released from the hospital. One 
commenter expressed concern about radioactive materials volatilizing 
from containers of urine. Another commenter noted that children or 
pregnant women could be subject to increased risk from excreta stored 
in the home if the exemption were withdrawn. Seven commenters noted 
that, in addition to the radiological risks, collection and storage of 
patient excreta also could pose biological hazards.
    Twenty-seven of the commenters that supported the exemption noted 
the short half life of most radiopharmaceuticals, and most of these 
commenters hypothesized that the risk that radiopharmaceuticals could 
pose to sanitary system workers or members of the general public would 
be limited by their short half lives. Representatives of two hospitals 
indicated that approximately 90 percent of the radioactivity used at 
their hospitals was

[[Page 68360]]

in the form of Tc-99m, which has a half life of 6 hours, and that most 
of the remaining radionuclides used have a half-life on the order of a 
few days. Twenty commenters noted the soluble or dispersible nature of 
patient excreta and five commenters suggested the dilution of patient 
excreta that occurs in the sewer system affords ample protection to the 
public and to the environment.
    Four commenters remarked that, if NRC believes the regulation is 
adequate, as stated in the ANPR, there should not be a need to modify 
the exemption for patient excreta. Two commenters predicted 
restrictions on the release of patient excreta into sanitary sewers 
would not provide a significant benefit to public health and eleven 
commenters suggested the current exemption creates no environmental or 
public health hazard. One commenter remarked that none of the six case 
studies presented in the ANPR indicated that patient excreta released 
into sanitary sewers had caused a significant dose to any individual. A 
representative of a large health care organization noted that no 
complaints had been made about the sewage from any of the 
organization's hospitals, although the hospitals' effluents were tested 
by sanitary system staff routinely. Another hospital representative 
expressed the opinion that hospitals should not be required to monitor 
patient excreta because the practice causes undue anxiety in the 
patients, creates additional burdens for nursing staff, and is 
unnecessary because survey readings generally are low.
    Response: NRC acknowledges the commenters' support for the 
exemption for patient excreta, which supports the withdrawal of the 
ANPR.
    Comment: Fourteen commenters stated that elimination of the 
exemption would impose significant burdens on their facilities' 
operations. Commenters expressed concern about the costs of building 
holding tanks for excreta, building separate plumbing systems, 
retraining workers, and employing additional workers to manage patient 
excreta. One commenter remarked that facilities would also incur the 
cost of hiring professionals to assess their current waste management 
practices and to recommend changes that would be needed to comply with 
new regulations. Three commenters remarked that medical facilities may 
also incur the costs of increased NRC licensing fees and inspections. 
Several commenters suggested any net health benefits associated with 
eliminating the exemption could not justify the costs of controlling 
the excreta, particularly for patients being treated on an out-patient 
basis.
    Seven commenters predicted the costs of compliance with 
restrictions on release of patient excreta into sanitary sewers would 
cause a significant increase in health care costs for patients. Three 
commenters predicted that health care costs would increase both because 
of the increased infrastructure and labor required to manage patient 
excreta and because patients' hospital stays would be extended so that 
their excreta could be managed by hospital staff. A physician and 
member of the NRC's Advisory Committee on the Medical Uses of Isotopes 
(ACMUI) estimated that the national increase in health care costs would 
be approximately 4.5 billion dollars for patients undergoing 
therapeutic procedures and 62 billion dollars for patients undergoing 
diagnostic procedures, as of 1994. The American College of Nuclear 
Physicians and the Society of Nuclear Medicine jointly estimated that 
elimination of the exemption would cause an increase in health care 
costs of 5.9 billion dollars annually.
    One commenter expressed the concern that medical facilities may 
stop offering nuclear medicine services to avoid the legal consequences 
that could result if patients did not comply with restrictions on the 
release of excreta to sewer systems. Five commenters predicted that it 
would be difficult to compel patients being treated on an out-patient 
basis to store their excreta for decay or return it to a licensed 
facility. One commenter expressed the concern that strict controls over 
patients could infringe upon a patient's constitutional rights.
    Several commenters expressed the concern that elimination of the 
exemption would impact patient care. Four commenters expressed the 
opinion that, if the exemption were eliminated, the costs or logistical 
difficulties associated with managing patient excreta would cause many 
facilities to discontinue offering nuclear medicine services and could 
cause the end of nuclear medicine in the United States. Three 
commenters expressed the concern that elimination of the exemption for 
patient excreta would limit patient access to diagnostic and 
therapeutic nuclear medicine services and five commenters expressed the 
view that inaccessibility of nuclear medicine services would be far 
more detrimental to public health than any adverse health effects that 
could be averted by eliminating the exemption for patient excreta. One 
commenter noted that many facilities already have eliminated some 
clinical procedures because of the lack of access to low level 
radioactive waste disposal facilities. Two commenters expressed the 
concern that eliminating the exemption for patient excreta would 
diminish the quality of care that patients received if facilities 
limited patient doses to comply with restrictions on the radioactivity 
of patient excreta released into sanitary sewers. One commenter 
expressed the concern that patients may decline beneficial medical 
procedures because of an objection to collecting or having someone else 
collect their excreta. One commenter noted that patient well-being 
would be compromised if patients needed to remain in the hospital so 
that their excreta could be managed because it would prolong the time 
away from their families and jobs. Another commenter suggested the 
current exemption for patient excreta should be maintained until the 
impact on health care could be assessed.
    Response: NRC acknowledges the commenters' concerns about the 
potential costs, legal implications, and impacts on patient care that 
may be caused by removing the exemption for patient excreta. The 
exemption will be maintained because the ANPR is being withdrawn for 
the reasons previously explained.
    Comment: Three commenters suggested the effects of the exemption 
should be studied to determine if the exemption should be eliminated or 
modified. A representative of DOE recommended NRC maintain the 
exemption for the excreta of patients undergoing diagnostic procedures, 
but consider placing restrictions on the excreta of patients undergoing 
therapeutic procedures because they typically receive higher doses of 
radiopharmaceuticals. Another commenter remarked that it would be 
inconsistent of NRC to impose strict restrictions on the release of 
excreta by hospitalized patients if the excreta of patients being 
treated on an out-patient basis contributed more radioactivity to 
sanitary sewer systems. A representative of an association of POTWs in 
Minnesota stated that the organization is prepared to rely on NRC 
judgement about the appropriateness of the exemption once NRC has 
evaluated the amounts and types of radioactive materials released into 
sanitary sewers through patient excreta, but expressed concern that the 
ANPR indicated that the effects of the exemption had not been studied 
and would not be included in planned modeling efforts. The commenter 
also expressed the opinion that the safety of the exemption should be 
evaluated irrespective of the origin of the waste in medical uses. A

[[Page 68361]]

representative of the New York State Department of Environmental 
Conservation suggested that a range of possibilities, including 
retaining the exemption, eliminating the exemption, and modifying the 
exemption, should be evaluated in an Environmental Impact Statement 
(EIS). The commenter stated an EIS would provide a ``long-needed'' 
record of the rationale for the decision to exempt patient excreta from 
the sewer release restrictions and the expected impacts of the 
exemption on the environment and public health.
    Response: NRC acknowledges the suggested modifications to the 
exemption of patient excreta and the suggestion that an EIS should be 
performed. However, those suggestions will not be implemented because 
the ANPR is being withdrawn for the reasons previously explained.
    Comment: Two commenters suggested releases of radioactive materials 
into sanitary sewers should be regulated uniformly, irrespective of the 
origin of the wastes. One of the commenters questioned why the ANPR 
specifically stated that doses from patient excreta were expected to be 
``far below the NRC's dose limit'' when this description was equally 
appropriate for the discharges from other licensees. Another commenter 
remarked that, although it may be difficult for medical institutions to 
meet restrictions on the release of patient excreta, the releases 
should be regulated because they have been shown to contaminate sewage 
sludge. Another commenter provided measurements of I-131 in sewage and 
sludge in one municipality's POTW and expressed the concern that I-131 
could be a source of radiation exposure to sanitary system workers. The 
commenter also expressed the concern that, although it has a short half 
life, Tc-99m could cause significant radiation doses to workers exposed 
to sewage collection systems directly downstream of hospitals. In 
addition, the commenter expressed the concern that, because I-131 is 
very soluble, most of the I-131 that entered a POTW would be discharged 
in the treated effluent and that the POTW's effluent may, therefore, 
exceed NRC limits on the allowable releases of radioactivity to 
unrestricted areas. The commenter also expressed concern that many 
municipalities are not aware that releases of patient excreta are 
exempt from NRC restrictions and can be a significant source of 
radioactivity in wastewater.
    Response: NRC acknowledges the commenters' suggestion that the 
release of radioactive material should be regulated uniformly 
irrespective of its origin. However, NRC believes the exemption for 
patient excreta is appropriate because of the potential biological and 
radiological hazards associated with alternate methods of managing 
patient excreta. Additional limitations on the release of patient 
excreta into sanitary sewers are not being imposed for the reasons 
previously discussed. NRC appreciates the commenter's concern that 
municipalities may be unaware of the potential for patient excreta to 
contribute to the radioactivity of wastewater and sewage sludge. 
Section 3.2 of the ISCORS recommendations on managing radioactive 
material in sewage sludge and ash (EPA 832-R-03-002B) alerts POTW 
operators that a significant amount of the radioactivity discharged to 
POTWs that serve medical facilities can be discharged in the form of 
patient excreta.
    Comment: Two commenters suggested the exemption for patient excreta 
should be eliminated to minimize the release of man-made radioactivity 
to the environment. One commenter expressed concern about NRC's policy 
on allowing patients who had received nuclear medicine treatments to 
leave the hospital (described in NRC Information Notice 94-009). The 
commenter also expressed concern about specific incidents in which, the 
commenter believed, patients had not been warned that high residual 
radioactivity would result from the medical procedures they had 
undergone or had been told that releasing excreta to a septic system 
would not cause adverse health effects. The commenter remarked that, 
although the radionuclides used in nuclear medicine procedures may be 
short-lived, each contribution of radioactivity to wastewater increased 
the potential dose to a member of the public. Another commenter noted 
that the contribution of radiopharmaceuticals to the radioactivity of 
wastewater increases as the number of procedures performed increases. 
The commenter also remarked that, if the half-lives of radioisotopes 
used in medical procedures typically are short, as NRC stated in the 
ANPR, the burden of storing the excreta until the radioactivity decays 
to background levels should not be large.
    Response: NRC acknowledges the commenters' concerns about the 
potential effects of the release of patient excreta into sanitary 
sewers. However, NRC believes the current regulations are protective 
and has decided to retain the exemption and withdraw the ANPR for the 
reasons previously explained. The staff notes that comments about the 
regulations governing the release of nuclear medicine patients from the 
hospital are beyond the scope of this rulemaking.
    Comment: One commenter suggested patient ``vomitus'' should be 
included in the exemption for the release of patient excreta into 
sanitary sewers explicitly. Two additional commenters mentioned sweat, 
saliva, blood, tears, and nasal fluids, but did not make any specific 
suggestions about how those fluids should be addressed in NRC 
regulations.
    Response: The suggested change to the wording of the exemption will 
not be made because the ANPR is being withdrawn. However, NRC staff 
note that, in practice, the term ``patient excreta'' typically is 
understood to include situations when patients vomit.
    Comment: A representative of a company that manufactures equipment 
that removes radionuclides from hospital waste noted German law 
requires that radioactive materials be removed from hospital effluent 
before it is released into sanitary sewers.
    Response: NRC appreciates the information provided by the 
commenter. However, the exemption for patient excreta will be retained 
because the ANPR is being withdrawn for the reasons previously 
explained.
    Comment: Three commenters asked questions about the regulatory 
implications of potential modifications to the exemption of patient 
excreta from sewer release restrictions. Two commenters asked whether 
patients would be required to store their excreta at home until it 
decayed to background levels of radioactivity or if they would be 
required to return it to the medical facility at which they were 
treated. Two commenters asked whether the homes of nuclear medicine 
patients would need to be monitored to ensure that proper waste 
disposal procedures had been followed. One commenter asked if the 
elimination of the exemption would result in changes to 10 CFR 35.75. 
The commenter also asked whether restrictions would apply to all 
patients treated with radiopharmaceuticals, irrespective of the dose 
they had received. The commenter also asked how a licensee would 
calculate the radioactivity released by each patient and whether 
records of the releases would need to be maintained by the licensee.
    Response: NRC acknowledges the many questions on this issue, but is 
not responding to them because the ANPR is being withdrawn.
    Comment: One commenter suggested NRC should exempt the excreta of 
animals used in biomedical research from the restrictions governing the

[[Page 68362]]

release of radioactive material into sanitary sewers.
    Response: NRC notes that this comment is beyond the scope of this 
rulemaking.

(5) General Comments

    In addition to comments on the topics discussed in the ANPR, NRC 
received a number of comments on other aspects of the release of 
radioactive material into sanitary sewers. These comments are addressed 
in this section.
    Comment: Sixteen commenters expressed the opinion that the current 
regulations governing the release of radioactive materials into 
sanitary sewers are adequate and should not be changed. To support this 
view, commenters remarked that the number of incidents of contamination 
is small compared to the number of POTWs receiving radioactive 
materials and that the doses received in those instances are believed 
to be low. Commenters also suggested the regulations should not be 
changed in response to a small number of cases of contamination, 
especially if some of those cases involved violations of the applicable 
regulations. One commenter noted that modeling results described in 
NUREG/CR-5814 indicate that releases of radionuclides used in 
biomedical research are expected to result in doses below the ALARA 
guidelines in NRC Regulatory Guide 8.37. A representative of the Texas 
Department of Health suggested the regulations should not be changed 
unless modeling results demonstrated that exposures other than 
ingestion could cause an annual dose greater than 5 mSv (500 mrem). Two 
commenters suggested the risk of adverse health effects associated with 
exposure to radioactive material released into sanitary sewers should 
be evaluated in comparison to the health risks associated with exposure 
to hazardous chemical and biological materials in sewage and sludge. 
One commenter suggested the current limits are appropriate because the 
quantities and concentrations of radionuclides at affected POTWs appear 
to be within 10 CFR part 30 limits for general licensees.
    Response: NRC acknowledges the commenters' support for the current 
regulations, which supports withdrawal of the ANPR.
    Comment: Nine commenters, including a representative of DOE, 
suggested the changes made to 10 CFR part 20 in 1991 may have 
significantly reduced the potential for reconcentration of 
radionuclides in POTWs, and that resources should not be expended to 
address a problem that may have already been solved. Of these, five 
commenters noted that the ANPR did not include any information about 
contamination problems that had occurred since the modification of 10 
CFR part 20 and two commenters noted that most of the contaminants in 
the case studies presented in the ANPR were insoluble non-biological 
materials and would not meet current release criteria. Several 
commenters recommended NRC evaluate the effects of the lower discharge 
concentration limits and prohibition against discharging insoluble, 
non-biological materials into sanitary sewers before making additional 
changes to 10 CFR part 20. One commenter expressed the opposite view 
and stated that the NRC should not assume that the changes made to 10 
CFR part 20 in 1991 would eliminate contamination of POTWs with 
licensed radioactive materials.
    Response: NRC acknowledges the commenters' recommendation that it 
study the effect of the changes made to 10 CFR part 20 in 1991 on the 
amount of radioactive material at POTWs. The NRC staff notes that the 
ISCORS sewage sludge survey and dose modeling work were performed 
several years after the January 1, 1993, deadline for licensees to meet 
the revised requirements and should reflect the effects of the 1991 
revision of the regulation.
    Comment: Five commenters expressed the view that additional 
restrictions on the release of radioactive materials into sanitary 
sewers would not be consistent with efforts to keep doses ALARA. 
Several of the commenters predicted that doses to workers that were 
required to collect or prepare waste for disposal would be far greater 
than the collective dose that could be averted by more restrictive 
sewer release limits.
    Response: NRC acknowledges the commenters' opposition to additional 
restrictions on the release of radioactive materials into sanitary 
sewers, which supports the withdrawal of the ANPR.
    Comment: Four commenters stated that any additional restrictions on 
the release of radioactive material into sanitary sewers would have a 
significant negative impact on the facilities they represented. One 
commenter expressed the view that banning the release of radioactive 
material into sewers would impose a large financial burden on all 
biological research facilities and estimated that, as of 1994, 
alternative disposal methods would cost his company $150,000 to 
$300,000 annually. A representative of a nuclear laundry stated that 
additional restrictions on the release of radioactive material into 
sanitary sewers could have a serious detrimental effect on his company 
and its customers in nuclear laundries could no longer operate. Another 
commenter suggested new restrictions should be implemented gradually by 
adding new restrictions during license renewals.
    One commenter expressed concern that additional restrictions on the 
release of radioactive material to sewers would encumber facilities 
that perform medical research, and requested that educational and 
medical research institutions be exempted from the regulations because 
the long-lived radionuclides that had been detected in the cases 
described in the ANPR typically are not used by medical research 
facilities. The commenter also requested that, if medical research 
facilities were not exempted, more explicit guidance about the 
implications of the regulations on specific practices used in medical 
research facilities be provided by NRC. Another commenter proposed that 
the regulation should explicitly permit disposal of medical diagnostic 
products in aqueous mixtures that contain less than 370 kBq (10 
microcuries) of radioactivity and which are composed of isotopes with 
half-lives less than 61 days.
    Response: NRC acknowledges the commenters' information about the 
burdens that could be caused by additional restrictions on the release 
of patient excreta into sanitary sewers, which supports the withdrawal 
of the ANPR. The staff notes that requests for exemptions of certain 
classes of facilities or types of waste are beyond the scope of this 
rulemaking. NRC acknowledges that guidance written specifically for 
medical research facilities would be helpful to some licensees, but 
does not have plans or resources to develop such guidance.
    Comment: A representative of DOE expressed the view that the 
current rules are protective of public heath and safety and the 
environment, and noted that, if the provision for release of 
radioactive materials into sanitary sewers was not available, risks to 
the public would result from other waste management options. As an 
example, the commenter predicted elimination of the release of 
radioactive material into sewers would cause an increase in traffic 
accidents because of the need to transport more waste to LLW disposal 
facilities. However, the commenter also recommended NRC increase 
inspections of licensees' releases into sanitary sewers and perform 
additional analyses of potential doses to members of the public and 
sanitary system workers to ensure that adequate safety provisions are 
in place to preclude accidental discharge of large quantities of

[[Page 68363]]

radioactive material. The commenter also recommended NRC contact AMSA 
and industry trade groups to obtain additional information about 
variations and trends in wastewater treatment technologies, practices, 
and regulations.
    Response: NRC acknowledges the commenter's remarks regarding the 
risks that could result from additional restrictions on the release of 
radioactive material into sanitary sewers, which support the withdrawal 
of the ANPR. In accord with the commenter's suggestions, NRC 
participated in the ISCORS sewage sludge survey (NUREG-1775) and dose 
modeling report (NUREG-1783), the results of which provide a technical 
basis for withdrawing the ANPR. The staff acknowledges the suggestion 
regarding NRC inspection activities but notes the topic is beyond the 
scope of this rulemaking.
    Comment: A representative of NIH stated that, although NIH is a 
large facility conducting both biomedical research and medical 
diagnosis and treatment, and its usage of some isotopes fluctuates 
considerably, NIH has been able to manage its radioactive liquid wastes 
in compliance with NRC regulations. The commenter also stated that NIH 
uses large, centrally-located tanks to hold short-lived radionuclides 
for decay, and that NIH has been granted an exception to the total 
quantity limits that allows it to discharge a total of 296 GBq (8 Ci)
 annually.
    Response: NRC acknowledges the commenter's information regarding 
the adequacy of the current regulations governing the release of 
radioactive material into sanitary sewers.
    Comment: A commenter who was a member of ACMUI as well as a 
physician and professor of Radiological Sciences at the University of 
California, Los Angeles, expressed several concerns regarding the 
possible changes described in the ANPR. The commenter expressed the 
opinion that NRC resources would be better spent changing other parts 
of 10 CFR part 20 than by making the changes proposed in the ANPR. The 
commenter also stated that Agreement States had been reluctant to adopt 
the changes made to 10 CFR part 20 in 1991 because of unspecified 
problems with the revised rule. The commenter expressed concern that 
user fees were used to support a National Council on Radiation 
Protection study of the number of various types of nuclear medicine 
procedures performed annually as of 1989. The commenter also expressed 
concern that any change in NRC regulations governing the release of 
radioactive materials into sewers would later be changed by an EPA 
rule, and that NRC licensees would, in effect, pay for a rule twice by 
paying both NRC user fees and paying taxes to support EPA.
    The commenter asked why the NRC had published the ANPR and 
expressed concern that NRC wasted licensees' time by asking for data 
regarding various nuclear medicine procedures. The commenter stated 
that the data had been given to NRC in 1990 and asked why NRC did not 
use these data to derive concentrations of various radionuclides in 
sanitary sewage. The commenter also suggested NRC could request data 
regarding concentrations of radioactive materials in wastewater and 
sewage sludge from POTWs in Agreement States. In addition, the 
commenter suggested NRC review any proposed changes related to medical 
uses of isotopes with the ACMUI and expressed an unfavorable opinion 
about NRC's program to regulate medical uses of radionuclides.
    Response: NRC acknowledges the commenter's statements about the 
1991 revision to 10 CFR part 20 but notes that other parts of the 
regulation are beyond the scope of this rulemaking. A response to the 
commenter's displeasure at paying licensing fees to support this 
rulemaking is not needed because the ANPR is being withdrawn. The same 
applies to the commenter's concern that EPA would impact a change in 
NRC's regulations. Because the ANPR is being withdrawn, that concern is 
no longer applicable to this issue.
    NRC published the ANPR to invite comments and recommendations from 
interested parties on potential changes in the regulations governing 
the release of radioactive materials into sanitary sewers. In response 
to the commenter's concern about the time licensees may have spent 
responding to the ANPR, NRC notes that the ANPR invited comment but did 
not require a response. In addition, NRC notes that the ANPR invited 
comment on a variety of issues and was not limited to a request for 
information to support the derivation of concentrations of 
radionuclides in sewage.
    NRC acknowledges the commenter's suggestion that potential changes 
to the rule be discussed with the ACMUI, and the commenter's statements 
about NRC's program to regulate medical uses of radionuclides.
    Comment: Three commenters expressed the view that cases of 
contamination at POTWs demonstrate that the current regulations 
governing the release of radioactive material into sanitary sewers is 
inadequate. All three commenters expressed the concern that the 
regulations did not adequately protect the health and safety of POTW 
workers. In addition, a representative of AMSA expressed the concern 
that the current regulations could jeopardize the ability of POTWs to 
fulfill their environmental objectives. The commenter also expressed 
concern about NRC's involvement with existing cases of contamination 
and urged NRC to take a more active role in protecting POTWs from 
contamination with radionuclides.
    Each of the three commenters expressed the opinion that the current 
regulations also fail to protect POTWs from the legal and financial 
consequences of contamination of POTWs and POTW biosolids with 
radionuclides. Two commenters noted that the public ultimately bears 
the costs associated with contamination of POTWs and one estimated that 
billions of dollars of public funds could be required to dispose of 
contaminated sludge and decontaminate POTWs. A representative of the 
City of Oak Ridge outlined the history of contamination of the Oak 
Ridge POTW with Co-60, Cs-137, uranium isotopes, and I-131 from 1984 to 
1994. The commenter noted that, as of 1994, disposal of wastewater 
treatment sludge cost the City of Oak Ridge approximately $100,000 per 
year, primarily because of radioactive contamination. The commenter 
stated that, because of this expense, the city is in the process of 
implementing its own limits to control releases of radioactive 
materials into the sanitary sewers and provided a reference that 
describes the approach that has been taken to control radioactive 
materials through the municipality's industrial pretreatment program.
    A representative of the Northeast Ohio Regional Sewer District 
noted that, although no significant health or safety problems had been 
found to result from the contamination at the district's Southerly 
Facility, the district has had to manage difficult regulatory issues 
and concerns from the public and from workers that had cost the 
district, as of 1994, $1.5 million to resolve. The commenter remarked 
that the sanitary district had over one hundred thousand cubic meters 
(4 million cubic feet) of Co-60 contaminated ash at its Southerly 
Facility and had recently discovered contamination at another one of 
its POTWs. The commenter expressed the view that the District's 
problems were attributable to inadequate regulations or ineffective 
enforcement by NRC and suggested that major revisions to both 10 CFR 
part 20 and to NRC's enforcement program were overdue.

[[Page 68364]]

    Response: NRC acknowledges the commenters' concerns about cases of 
contamination and protection of POTW workers. However, NRC believes 
that the restrictions on the forms of material suitable for release and 
lower concentration limits established in the 1991 revision to 10 CFR 
part 20 have reduced the potential for significant contamination of 
POTWs or sewage sludge with radionuclides. Although additional 
restrictions on the release of radioactive material into sanitary 
sewers will not be implemented, Section 7.2 of the ISCORS 
recommendations on management of radioactive materials in sewage sludge 
and ash (EPA 832-R-03-002B) provides guidance to assist POTW operators 
in reducing sources of radiation entering their treatment facilities. 
Comments about NRC's enforcement program are beyond the scope of this 
rulemaking.
    NRC acknowledges the information provided by the City of Oak Ridge 
regarding the POTW's industrial pretreatment program. Information about 
the program is summarized in Appendix F of the ISCORS recommendations 
on management of radioactive materials in sewage sludge and ash (EPA 
832-R-03-002B).
    Comment: A representative of a sanitary district stated that, 
contrary to the position taken by NRC in the ANPR, many cases of 
contamination of POTWs are the result of relatively basic wastewater 
treatment technologies. In addition, the commenter expressed the view 
that NRC's emphasis on the concept of ``reconcentration'' as the cause 
of contamination problems is misleading and noted that, at one POTW in 
the district, it appeared that particles of Co-60 were removed from the 
sewage through settling, as other solids are removed, rather than 
through reconcentration of dissolved cobalt or agglomeration of fine 
particles. The commenter expressed the view that the new restrictions 
on the forms of materials suitable for release into sanitary sewers may 
prevent many problems with insoluble materials such as Co-60 if the 
regulations are properly enforced.
    Response: NRC acknowledges the commenter's concern that the term 
``reconcentration'' was used in the ANPR to describe all processes by 
which the concentration of radionuclides in sewage sludge or ash could 
be increased on volumetric basis. NRC understands that radioactive 
materials may be concentrated by common wastewater treatment processes, 
as discussed in NUREG/CR-6289.
    Comment: Seven commenters expressed the view that discharges of 
radioactive materials into sanitary sewers should be regulated locally. 
Two commenters suggested that, because relatively few cases of 
contamination had been observed, it appeared that the cases could be 
resolved without NRC involvement. One commenter expressed the view that 
local control would be easiest to implement if the problematic 
discharges involved other hazardous, nonradioactive materials.
    Five commenters, including a representative of AMSA, expressed the 
opinion that POTWs should have the legal authority to establish local 
limits for the release of radioactive material into sanitary sewers. 
Three of the commenters expressed the concern that, although 
municipalities are held responsible for the disposal or beneficial use 
of POTW sludge, the municipalities have no control over the 
radioactivity of materials discharged to the sewer system that affect 
sludge quality. One commenter expressed the concern that the existing 
regulatory framework is inadequate because NRC maintains that the party 
in possession of the radioactive material is responsible for 
remediation, offers no assistance to POTWs that have been contaminated 
by a licensee's effluent, and states that the AEA indicates that its 
regulations preempt more restrictive local regulations. The commenter 
expressed concern that NRC has indicated that this position would not 
change even if NRC had proof that material was illegally discharged by 
a licensee and that a POTW's only recourse to recover remediation costs 
is to take legal action against the discharger. One of the commenters 
suggested NRC should either assume responsibility for disposing of 
radioactive sludge generated in POTWs as a result of ``errant 
discharge'' from NRC licensees or allow POTWs to regulate the discharge 
of radioactive materials into sewer systems. The other commenter 
suggested that, in cases in which the reuse or disposal of sludge is 
restricted because of its radiological contamination, NRC should 
cooperate with EPA to help affected POTWs establish local discharge 
limits to protect the traditional method of disposal or reuse of the 
biosolids.
    Another commenter stated that it was not necessary, feasible, or 
appropriate for NRC to develop new regulations that would limit the 
disposal of radioactive material into sanitary sewers because POTWs 
already had the legal authority and mandate to establish and enforce 
appropriate pretreatment standards that would prevent contamination of 
POTWs or sewage sludge, pursuant to the Clean Water Act (33 U.S.C. 
1317(b) and (d) and 1319) and EPA Clean Water Act Standards (40 CFR 
Part 403).
    Response: NRC acknowledges the commenters' concern about the power 
that local authorities have to regulate the release of radioactive 
material to their POTWs. The U.S. Supreme Court has held that, for 
certain activities covered by the AEA, Federal authority preempts other 
regulatory authorities whose purpose is radiation protection. It is 
difficult to predict whether unusual cost to the POTW caused by 
radioactive effluent discharges would be a sufficient reason to impose 
more restrictive discharge limits than those permitted under Federal 
law because there are no Federal cases in which the specific facts 
corresponded to the scenarios faced by local POTW authorities. More 
information on this issue is presented in Chapter 4 and Section 7.2 of 
the ISCORS recommendations on management of radioactive materials in 
sewage sludge and ash (EPA 832-R-03-002B).
    Comments regarding NRC's responsibility for the disposal of 
contaminated sludge are beyond the scope of this rulemaking. As 
discussed in Chapter 7 of the ISCORS recommendations (EPA 832-R-03-
002B), in individual cases of contamination, legal counsel should be 
consulted to determine if dischargers may be liable for portions of 
remediation costs.
    Comment: One commenter recommended NRC exempt POTWs from any 
regulations that would apply to material released into their systems 
because the potential benefits of regulating POTWs would not justify 
the costs.
    Response: This suggestion is beyond the scope of this rulemaking.
    Comment: Five commenters, including a representative of AMSA, 
expressed the view that POTWs should be able to apply the same type of 
pretreatment standards to radionuclides in licensees' effluent that are 
applied to toxic materials discharged into sewer systems by industrial 
dischargers as part of EPA's NPDES program. Commenters noted that local 
limits can account for the number of licensees discharging to a single 
POTW, the total flow into a POTW, and the effects of various treatment 
process on radionuclide reconcentration. Three commenters noted that, 
in general, local restrictions on discharges of pollutants to POTWs are 
established by determining an allowable load of a pollutant to a POTW 
that will not create a violation of the POTW's effluent limit and not 
interfere with disposal or reuse of the POTW's

[[Page 68365]]

biosolids, and then allocating that limit among industrial facilities 
that discharge effluent to the POTW. Two commenters expressed the view 
that the same process should be used to develop individual limits for 
each radionuclide, taking into account each radionuclide's specific 
activity, half-life, and solubility. One commenter noted that this 
procedure cannot be followed with radioactive materials because no 
``acceptable'' levels of radionuclides in sludge have been established. 
Another commenter recommended NRC coordinate any future regulations 
affecting sanitary sewer discharges with EPA requirements for Clean 
Water Act discharges, including Categorical Standards, NPDES permits, 
and regulations pertaining to sewage sludges.
    Two commenters suggested that, because setting limits for 
radioactive materials will be new to many POTWs, NRC should provide 
guidance on establishing local limits on the release of radioactive 
materials into sanitary sewers. A representative of AMSA suggested a 
number of topics that the recommended guidance should address and 
recommended NRC consider two EPA resources used to develop limits on 
industrial discharges to POTWs.
    Response: This comment includes detailed recommendations about the 
creation of a program in which the release of radionuclides into 
sanitary sewers would be regulated by local, rather than Federal, 
authorities, and is beyond the scope of this rulemaking. Although 
guidelines for the development of local limits under such a program 
have not been developed, many of the topics the commenters requested be 
included in such guidance are included in the ISCORS recommendations on 
management of radioactive materials in sewage sludge and ash (EPA 832-
R-03-002B), as is information about local pretreatment programs 
established in Albuquerque, NM, St. Louis, MO, and Oak Ridge, TN.
    Comment: One commenter was concerned that system-specific discharge 
limits could be difficult to implement if, as is done in the NPDES 
process, discharge limits are based on the ``waste assimilative 
capacity'' of the receiving waterway, which, the commenter stated, 
could be difficult to determine. The commenter also expressed concern 
that licensees would need to obtain prior approval for sewer 
discharges, and that regulatory agencies would need to keep track of 
separate discharge allotments for each licensee and any changes to each 
POTW's treatment processes. The commenter noted that an alternative to 
establishing system-specific discharge limits would be to set activity 
limits so low that regulatory limits or ALARA goals for public doses 
would be met, irrespective of the wastewater treatment process used, 
the capacity of the receiving POTW, or the number of dischargers 
discharging to the POTW. The commenter noted that this approach would 
not require as much regulatory oversight and suggested these approaches 
should be evaluated in an EIS.
    Response: NRC acknowledges the commenter's concerns about the 
difficulties involved with implementing system-specific discharge 
limits. An EIS that evaluates the alternatives will not be developed 
because the ANPR is being withdrawn for the reasons previously 
discussed.
    Comment: One commenter asked for clarification as to how the 
revised rule would relate to NRC decommissioning standards and various 
EPA rules and suggested NRC hold public hearings on the issue.
    Response: NRC is not responding to the request for clarification on 
the relationship between the proposed rule and EPA or NRC standards 
because the ANPR is being withdrawn.
    Comment: Ten commenters expressed the view that any change to the 
regulations governing the release of radioactive materials into 
sanitary sewers should have a solid technical basis. Three commenters 
recommended NRC delay decisions about the need for modifications to the 
regulation until NUREG/CR-6289, which was incomplete at the time, was 
made available to licensees. Two commenters expressed concern that the 
ANPR was offered without a significant risk assessment. Six commenters 
recommended that any proposed change in the regulation should be based 
on a realistic assessment of either the collective dose or the risks to 
members of the public and POTW workers that the new regulations would 
avert. Two commenters expressed the concern that changes to the 
regulations would be made for reasons other than technical reasons, 
including regulatory convenience, a perception of public opinion, or 
political pressure.
    A representative of the New York State Department of Labor remarked 
that some of the regulatory changes proposed in the ANPR would be 
complex for both licensees and regulatory agencies to implement and, 
therefore, should not be undertaken without a without a firm technical 
basis. The commenter expressed the view that, except for the exemption 
of patient excreta, all of the options discussed in the ANPR required 
more analysis before NRC would have sufficient information on which to 
base a decision. The commenter expressed the opinion that frequent 
changes in the same regulation are especially burdensome for licensees 
and urged NRC to perform the necessary analyses before changing the 
rule again. Representatives of the New York State Energy Office and New 
York State Department of Environmental Conservation encouraged NRC to 
develop an EIS to evaluate the options discussed in the ANPR. The 
representative of the New York State Department of Environmental 
Conservation remarked that the current regulations, including the 
revisions made in 1991, had never undergone a full environmental 
review.
    Two commenters expressed the concern that the current limits on the 
discharge of radioactive material to sewers do not reflect the hazards 
radioactive materials could pose in a POTW or after release to the 
environment. The commenters recommended NRC initiate a study that would 
include a POTW hazard identification and assessment, exposure and 
toxicity assessments, and a risk characterization. The two commenters 
also recommended NRC study the fate and transport of radionuclides in 
sewers, POTWs, and the environment. A representative of the City of Oak 
Ridge provided a reference that discussed the fate and transport of 
radionuclides in the municipality's POTW. A representative of AMSA 
recommended NRC cooperate with EPA, POTWs, and affected industries to 
assess the exposure and contamination pathways of radionuclides, and 
the impact of radioactive materials on wastewater treatment processes.
    Response: NRC acknowledges the commenters' view that the 1991 
revision to the regulations governing the release of radioactive 
materials into sanitary sewers should have been based upon detailed 
risk analyses. As discussed previously, NRC cooperated with 
representatives of EPA and POTWs in developing the ISCORS survey and 
dose modeling project to assess the radioactive contamination in POTWs 
and pathways for exposure of POTW workers and members of the general 
public to radionuclides released into sanitary sewers. The results of 
these analyses served as the technical basis for the withdrawal of the 
ANPR. An EIS for the rulemaking will not be performed because the ANPR 
is being withdrawn for the reasons previously discussed.
    Comment: Three commenters, including a representative of AMSA,

[[Page 68366]]

recommended NRC study the extent of the use of sewer discharges and 
contamination of POTWs around the country. The representative of AMSA 
suggested that, because NRC had acknowledged that it did not know how 
many POTWs in the country were contaminated with radionuclides and 
because it would be inappropriate to develop national standards based 
on contamination in a few isolated cases, NRC should establish a task 
force composed of NRC and EPA staff as well as representatives of POTWs 
and licensees to study the nature and extent of radioactive 
contamination of POTWs nationally. Three commenters recommended NRC 
determine which licensees release radioactive material into sanitary 
sewers and two of these commenters recommended NRC make the information 
available in a national database. Of these commenters, one suggested 
the database should be similar to the EPA's Toxic Release Inventory and 
the other suggested the database should include information about the 
mass of each radionuclide discharged per year by each licensee, the 
volume of the licensee's discharge, and the licensee's POTW service 
area. A representative of one utility district expressed concern that, 
as of 1994, the NRC had not been able to provide a list of the 
licensees discharging into the district's sewer system and that the 
district had, therefore, been unable to initiate an appropriate 
monitoring program.
    Response: NRC acknowledges the commenters' request for a national 
database, but notes that a database that contains information about 
releases of radioactive material into sanitary sewers by licensees is 
not being developed. As discussed in Section 5.1 of the ISCORS 
recommendations on management of radioactive materials in sewage sludge 
and ash (EPA 832-R-03-002B), POTW operators are encouraged to contact 
the applicable NRC Regional Office, appropriate State Radiation Safety 
Office, and any nearby DOE facilities if they have questions about the 
sewer releases of facilities in the POTW's service area that use 
radioactive materials.
    Comment: One commenter requested that, because NRC had just begun 
to study the fate of radionuclides in POTWs and because NRC did not 
know which of its licensees discharged materials into sanitary sewers, 
a moratorium be imposed on the disposal of radioactive material into 
sanitary sewers until NRC had the information necessary to help POTWs 
develop protective limits.
    Response: NRC notes that this comment is beyond the scope of this 
rulemaking.
    Comment: One commenter expressed concern that the assumptions used 
in 10 CFR part 20 ignored exposures to children, fetuses, elderly, 
people with existing body burdens of radioactive material, and 
individuals in other sensitive groups. The commenter expressed concern 
that the risk of birth defects from ionizing radiation had been limited 
to only two generations in NRC analyses and stated that the greatest 
number of birth defects will be seen in generations beyond the next 
two. The commenter also expressed the view that NRC should consider 
non-cancer and nonfatal cancer health effects in risk calculations and 
expressed concern that these effects were not considered in the 
promulgation of 10 CFR part 20.
    Response: The commenter's remarks about NRC's development of 
standards for the protection against radiation are beyond the scope of 
this rulemaking.
    Comment: Three commenters recommended NRC perform a cost/benefit 
analysis of alternatives to the release of radioactive materials into 
sanitary sewers before proceeding with a rulemaking and two of those 
commenters expressed the view that the proposed changes could not be 
justified by either a risk analysis or cost/benefit analysis. One 
commenter urged NRC to apply the backfit provisions that apply to power 
reactors to a broader scope of rulemaking decisions, and expressed the 
view that the alternatives suggested in the ANPR could not be justified 
in a backfit analysis.
    Response: NRC is not performing a cost/benefit analysis or risk 
analysis because the ANPR is being withdrawn for the reasons previously 
discussed. The staff note that the commenter's opinions about NRC's 
backfit provisions are beyond the scope of this rulemaking.
    Comment: One commenter expressed the concern that limits based on 
overly-simplified dose models could be overly-restrictive and could 
cause unintended harm to the public by limiting beneficial uses of 
radioactive materials. The commenter suggested NRC consider the ``total 
societal impact'' of its release limits, and expressed the view that 
NRC and other regulatory agencies typically perform inadequate 
assessments of the financial impacts of their rules. The commenter 
added that NRC should not avoid this responsibility by claiming that 
the AEA does not give it the responsibility to evaluate the total 
societal impact of its rules, because evaluation of cost, benefit, and 
total societal impact is inherently included in the concept of 
maintaining doses ALARA.
    Response: NRC acknowledges the commenter's concern about the 
adequacy of financial impact analyses performed by NRC and other 
regulatory agencies. NRC staff agree that, as defined in 10 CFR 
20.1003, the term ``ALARA'' indicates consideration of societal and 
socioeconomic impacts.
    Comment: Five commenters expressed the opinion that, in general, 
any changes to the regulations should allow less radioactive material 
to be released into sanitary sewers. Reasons for this position included 
new information about the adverse effects of chronic exposure to low 
levels of ionizing radiation, information about the synergistic effects 
of radiation and chemical pollutants, and concern about the cumulative 
effects of multiple sources of radiation on public health and the 
environment. Two commenters suggested that all radioactive waste should 
be isolated in secure storage or disposal facilities. Another commenter 
stated that NRC should not allow environmental build-up of multiple 
sources of radiation even if each, individually, could be dismissed as 
being minimal. One commenter stated that his organization had commented 
on the revision of 10 CFR part 20 repeatedly and that it remains 
concerned that the allowable concentrations of many radionuclides in 
air and water increase.
    Response: The ANPR is being withdrawn for the reasons previously 
explained. Comments about the basis for NRC's standards for the 
protection against radiation are beyond the scope of this rulemaking.
    Comment: Four commenters expressed the opinion that the potential 
burden that additional restrictions on the release of radioactive 
material into sanitary sewers would impose on licensees is secondary to 
the primary goal of protecting public health and safety and should be 
given little weight in the evaluation of whether additional 
restrictions should be established. Two commenters expressed concern 
that, in the ANPR, NRC made several inquiries about the impacts of new 
restrictions on licensees without expressing a similar interest in the 
potential impacts of the release of radioactive material into sanitary 
sewers on other parties. One of the commenters expressed the view that 
the concern for licensees may be misplaced because it is 
municipalities, and not licensees, that ultimately bear the costs of 
disposal of contaminated sludge and POTW decontamination. The commenter 
also remarked that it appeared to be more appropriate for

[[Page 68367]]

licensees, rather than the public, to bear the expense of the disposal 
of radioactive materials used by licensees. The other commenter 
suggested NRC should have solicited comments regarding the potential 
impact of the regulations on public health, healthcare costs, 
contamination of agricultural land, restriction of land uses, and 
environmental degradation. Two commenters stated that it would be 
inappropriate for NRC to allow any risk to members of the public to 
lessen economic or regulatory burden on licensees. Another commenter 
noted that, in cases in which contamination of a POTW has been 
discovered, licensees must recognize that safety of the community is 
more important than the desire for a licensee to use its current 
disposal options.
    Response: NRC acknowledges the commenters' concerns regarding the 
specific requests for comment in the ANPR. With regard to the 
consideration given to the potential effects of changes in the 
regulation on public health and the environment as compared to 
potential burdens on licensees, the NRC staff notes that a significant 
effort was made to study the potential effects of the release of 
radioactive material into sanitary sewers on the public and POTW 
workers in conjunction with the ISCORS reports that were described 
previously. Comments about the basis for NRC's standards for the 
protection against radiation are beyond the scope of this rulemaking.
    Comment: Six commenters suggested that detection of radionuclides 
at a few POTWs is an insufficient reason to impose additional 
restrictions on the release of radioactive material to sanitary sewers. 
These commenters stated that radioactivity can be measured at very low 
levels that are not expected to cause a significant adverse health 
effect for any individual. One commenter stated that lowering release 
limits to values that are significantly lower than limits needed to 
protect the public makes it more difficult for licensees to assure 
compliance of medical research and clinical staff with radiation safety 
procedures and undermines the public's confidence in realistic exposure 
or activity standards. Another commenter recommended NRC acknowledge 
that the risks caused by radioactivity in sewage sludge are small 
compared to the risks associated with the extra handling and 
transportation of waste that would occur if releases of radioactive 
material to sanitary sewers were eliminated.
    One commenter also suggested that, because radioactivity can exist 
in sewer systems and POTWs without causing a significant dose to any 
individual, and because there are beneficial uses of radioactive 
materials, that it might be better to attempt to build public 
acceptance of the current practices than it would be to lower release 
limits or eliminate sewer discharge. Another commenter suggested 
incidents of contamination should be handled in a consistent, routine 
way without undue alarm. A representative of DOE predicted that any 
discovery of radioactive contamination of sewage pipes or sewage 
treatment plants is likely to result in regulatory concern, even if the 
possible doses are tiny, because it may take time to determine whether 
the contamination poses a threat to public health and safety.
    Response: NRC acknowledges the commenters' opinions, which support 
the withdrawal of the ANPR. The staff acknowledges the commenters' 
recommendations about proper treatment of cases of contamination, but 
notes they are beyond the scope of this rulemaking.
    Comment: Three commenters addressed the potential for accidental 
releases of radioactive material into sanitary sewers. One commenter 
hypothesized that the case studies presented in the ANPR may have been 
the result of abnormal events and expressed the opinion that no amount 
of regulation, planning or notification can prevent inadvertent 
releases that result from system failures or other errors. Another 
commenter suggested NRC should realize that, irrespective of its 
regulations, an individual is likely to find a way to defeat 
``reasonable safeguards.'' Another commenter expressed concern that the 
modeling results described in the ANPR did not account for the 
potential for accidental releases in excess of the 10 CFR part 20 
limits and suggested the reported calculated doses may be 
underestimates.
    Response: NRC acknowledges the commenters' statements about the 
possibility of accidental releases. NRC staff note that its inspections 
are designed to ensure licensees' operations are conducted safely and 
in accordance with good practices and license conditions. With respect 
to the commenter's concern that the dose modeling results discussed in 
the ANPR do not include the effects of accidental releases, NRC staff 
note that the doses estimated in NUREG/CR-1548 did not include the 
potential effects of accidental releases; however, the doses reported 
in the ISCORS dose modeling report (NUREG-1783) were based on observed 
levels of radioactivity measured in conjunction with the ISCORS sewage 
sludge survey (NUREG-1775) and, therefore, reflect any accidental 
releases that may have been made to the 313 POTWs surveyed.
    Comment: Seven commenters addressed LLW disposal. Four commenters 
noted that additional restrictions on the release of radioactive 
materials to sewers would increase the amount of low level radioactive 
waste that would need to be disposed of in some other way. Two 
commenters recommended NRC evaluate the options proposed in the ANPR in 
the context of the risks associated with the disposal of low level 
nuclear waste and the limited capacity of LLW disposal facilities. Two 
commenters noted that many licensees had, as of 1994, very limited or 
no access to LLW disposal facilities and one of the commenters noted 
that licensees without access to a LLW disposal facility would need to 
store waste on site indefinitely. Three commenters noted that 
additional restrictions on the release of radioactive materials into 
sanitary sewers would be especially burdensome because the facilities 
they represented lacked access to LLW disposal sites. One commenter 
stated that sewer disposal is the primary way that many medical 
research and biotechnology laboratories minimize generation of LLW.
    One commenter expressed the concern that the use of sanitary sewer 
disposal of radioactive material would increase because of the high 
cost and limited availability of LLW disposal. The commenter noted that 
the release of radioactive material into sanitary sewers itself can 
lead to the creation of large volumes of LLW by contaminating sludge. 
Another commenter opposed the implication that sanitary sewer disposals 
would be used as a means of relief from the relative inaccessibility of 
LLW disposal and noted that most types of LLW do not meet the 
requirements for release into sanitary sewers.
    Response: NRC acknowledges the commenters' concerns regarding the 
impact that the proposed changes would have because of some licensees' 
lack of access to LLW disposal facilities. These comments support the 
withdrawal of the ANPR.
    NRC also acknowledges the commenter's concern that limitations on 
LLW disposal could lead to an increase in the release of radioactive 
material to sanitary sewers. The NRC staff notes that the results of 
the ISCORS sewage sludge survey (NUREG/CR-1775) do not indicate that 
the frequency of POTW contamination incidents has increased since the 
commenters' remarks were made in 1994.
    Comment: Five commenters expressed the opinion that licensees

[[Page 68368]]

should bear all costs associated with waste disposal. One commenter 
suggested NRC's descriptions of case studies should include a 
description of the financial costs associated with the contamination 
and should indicate the party paying the remediation costs. Two 
commenters stated that NRC licensees should bear the costs of data 
collection, data reporting, and worker training needed to implement any 
new NRC studies or regulations needed to protect POTWs from 
contamination. Two commenters expressed the view that licensees should 
pay to have monitoring equipment installed at POTWs.
    Response: NRC acknowledges the commenter's suggestion that NRC's 
descriptions of case studies should include information about the 
economic aspects of the contamination and notes that some information 
about remediation costs is provided in Section 1.2 of the ISCORS 
recommendations on management of radioactive materials in sewage sludge 
and ash (EPA 832-R-03-002B). Comments regarding the costs associated 
with implementation of new sewer release restrictions are moot because 
the ANPR is being withdrawn.
    Comment: Six commenters expressed opinions about NRC enforcement 
actions. A representative of DOE stated that it was unclear whether one 
or more of the incidents described in the ANPR involved violations of 
the regulations, and suggested enhanced inspections, and not additional 
rulemaking, would be the most appropriate way to eliminate 
contamination of POTWs. Three commenters suggested NRC or POTWs should 
verify licensee's reported discharges into sanitary sewers and one 
commenter suggested compliance with NRC regulations should be 
demonstrated at the licensee's outfall into the sanitary sewer system 
so that POTWs would not be impacted and would not need to implement 
special controls. Two representatives of POTWs noted that POTWs 
routinely sample the effluent of major industrial users as part of 
their industrial pretreatment programs. Another commenter suggested NRC 
should assist POTWs with monitoring of licensee's effluents and 
enforcement of the discharge limits.
    Response: NRC notes that suggestions about inspection and 
enforcement activities are beyond the scope of this rulemaking.
    Comment: Six commenters made specific suggestions about monitoring. 
Two commenters suggested licensees' outfalls and potable water intakes 
should be monitored, and three commenters suggested monitoring also 
should occur at POTWs. One of the commenters that advocated monitoring 
at POTWs expressed the view that monitoring would limit uncertainty in 
model results and would facilitate the study of the effects of influent 
radionuclide form and quantity on POTW worker doses. The commenter also 
suggested licensees should be encouraged to provide dosimetry and 
elementary radiation safety training to POTW workers. One commenter 
expressed the opinion that radionuclides in licensees' effluents should 
be monitored to record the highest concentrations discharged and 
facilitate a regulator's ability to link discharges with their sources. 
Three commenters suggested the radioactivity of sewage sludge should be 
monitored. One commenter expressed concern about the radioactivity of 
an engineered wetland used to treat wastewater in his town.
    Response: Recommendations regarding locations for monitoring a 
licensee's effluent are beyond the scope of the proposed rulemaking.
    Comment: A representative of the New York State Department of 
Environmental Conservation recommended that the Notice of Proposed 
Rulemaking for any change to the regulation governing the release of 
radioactive material into sanitary sewers notice, for public comment, 
the compatibility category NRC intends to apply to each provision so 
that Agreement States and other interested parties can participate in 
decisions about compatibility requirements. The commenter stated that, 
as of 1994, Agreement States were required to develop regulations that 
were compatible with the revised 10 CFR part 20 without NRC having 
determined compatibility requirements and stated that this type of 
situation must not recur.
    Response: NRC acknowledges the commenter's recommendation that 
intended compatibility categories be included in Notices of Proposed 
Rulemaking. Compatibility categories for the options discussed in the 
ANPR are moot because the ANPR is being withdrawn.
    Comment: One commenter expressed a number of concerns about the 
case studies described in the ANPR. Concerns raised by the commenter 
included specific exposure pathways that may not have been included in 
the dose analyses, the appropriateness of NRC's comparison of doses 
with background radiation, and the concern that calculated doses to 
individuals could have been higher if the sludge to which they were 
exposed included radiation from multiple sources. The commenter 
expressed the view that radioactivity in the environment may increase 
because of human activity, and that it would be inappropriate to 
consider manmade contributions of radioactivity to the environment in 
the calculation of ``background'' radiation, or to allow releases 
because they would be minimal in comparison to background radiation. 
The commenter also remarked that the cases of contamination that had 
occurred in Washington, DC, and Cleveland, OH, indicated the potential 
for contamination to be significant to large populations. In addition, 
the commenter asked specific questions about the assumptions used to 
calculate the doses resulting from the case studies discussed in the 
ANPR and what sources of radiation NRC included in its calculation of 
``background radiation.''
    Response: The commenter's concerns about the doses calculated in 
the case studies are no longer applicable because more recent studies 
served as the technical basis for the withdrawal of the ANPR. NRC 
acknowledges the commenter's concern regarding contamination at POTWs. 
The commenter's specific questions about the modeling assumptions used 
to calculate doses for the case studies discussed in the ANPR are 
addressed in NUREG/CR-1548. NRC notes that its definition of 
``background radiation,'' provided in 10 CFR 20.1003, excludes 
contributions of radioactivity from source, byproduct, or special 
nuclear materials regulated by NRC.

    For the reasons cited in this document, NRC withdraws this ANPR.

    Dated at Rockville, Maryland, this 11th day of October, 2005.

    For the Nuclear Regulatory Commission.
Luis A. Reyes,
Executive Director for Operations.
[FR Doc. 05-22432 Filed 11-9-05; 8:45 am]
BILLING CODE 7590-01-P