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OCR for page 1
Executive Summary
The U.S. Nuclear Regulatory Commission (USNRC) and its predecessor,
the U.S. Atomic Energy Commission (AEC), have attempted since the 1970s to
give greater uniformity to the policy and regulatory framework that addresses
the disposition of slightly radioactive solid material.] The issue remains unre-
solved and controversial. The USNRC has tried to issue policy statements and
standards for the release of slightly radioactive solid material from regulatory
control, while such material has been released and continues to be released
under existing practices. In 1980 the USNRC proposed regulatory changes to
deregulate contaminated metal alloys but withdrew them in 1986 and began
work with the Environmental Protection Agency (EPA) to develop more broadly
applicable federal guidance. In 1990 the USNRC issued a more sweeping policy,
as directed by the Low Level Radioactive Waste Policy Amendments Act of
1985 (LLWPAA), declaring materials with low concentrations of radioactivity
contamination "below regulatory concern" (BRC) and hence deregulated. Con-
gress intervened to set aside the BRC policy in the Energy Policy Act of 1992,
after the USNRC's own suspension of the policy. Subsequent attempts by
USNRC staff to build consensus among stakeholder groups as a basis for future
policy articulations were met by boycotts of stakeholder meetings, both in the
immediate aftermath of the BRC policy and again in 1999 during public hear-
1The phrase "slightly radioactive solid material" is used to mean objects that contain radionuclides
from licensed sources used or possessed by licensees of the USNRC and agreement states. These
materials typically contain radionuclides at low concentrations, and by virtue of these low concentra-
tions they can be considered for disposition as something other than low-level radioactive waste.
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2
THE DISPOSITION DILEMMA
ings on a new examination of the disposition of such materials. The only USNRC
standard addressing the disposition of slightly radioactive solid material is a
guidance document published in June 1974 by the AEC, whose regulatory au-
thority over civilian nuclear facilities the USNRC assumed upon its creation a
few months later in January 1975.
In August 2000, with another examination of this issue under way, the
USNRC requested that the National Research Council form a committee to pro-
vide advice in a written report. The National Research Council established the
Committee on Alternatives for Controlling the Release of Solid Materials from
Nuclear Regulatory Commission-Licensed Facilities to address this task. The
committee's task involved evaluating and providing recommendations on the
history of the technical bases and policies and precedents for managing slightly
radioactive solid material from USNRC-licensed facilities; the sufficiency of
technical bases needed to establish standards for release of solid materials from
regulatory control ("clearance standards") and the adequacy of measurement
technologies; the concerns of stakeholders and how the USNRC should incorpo-
rate them; and the efforts of international organizations on clearance standards.
The committee was also asked to examine the current system for release of
slightly radioactive solid material from regulatory control, to recommend whether
the USNRC should continue to use this system and to recommend changes if
appropriate. The committee's fact-finding process included two site visits to
waste brokering facilities and nearly 40 invited presentations from the USNRC,
the U.S. Department of Energy (DOE), and EPA staff; stakeholder organizations;
nuclear industry organizations; and other interested parties.
A brief discussion is needed to describe the types of facilities regulated by
the USNRC, the types of slightly radioactive solid material originating from
these facilities, and which facilities are their principal source. As noted, the
USNRC was split off from the AEC to regulate civilian nuclear facilities. It
currently regulates 103 operating nuclear power reactors and 36 operating non-
power reactors ("reactor licensees"), and approximately 5,000 specific materials
licensees, which use or possess source, special nuclear, or byproduct material.2
Some of the principal categories of facilities holding materials licenses include
measuring system gauges and instruments (1,698 licenses), medical applications
(1,556 licenses), and research and development facilities (474 licenses). Among
2Source material is uranium and thorium in natural isotopic ratios, or ores containing uranium and/
or thorium above 0.05 percent by weight. Special nuclear material is plutonium, enriched uranium,
and uranium-233. Byproduct material includes any radioactive material (except special nuclear ma-
terial) yielded in or made radioactive by the process of nuclear fission. A second category of
byproduct material is uranium mill tailings, added in 1978 ("ll(e)(2) materials"). The foregoing
definitions have been paraphrased from their original sources, the Atomic Energy Act and 10 CFR
Part 20, to provide greater clarity. Those sources should be consulted with regard to the legal mean-
ing and effect of these terms.
OCR for page 3
EXECUTIVE SUMMARY
3
the large facilities with materials licenses are 34 interim spent fuel storage facili-
ties, 18 uranium mills, 7 uranium fuel fabrication plants, 2 uranium hexafluoride
plants, and 2 uranium enrichment plants, all of which are components of the
nuclear fuel cycle. The USNRC' s agreement states3 license roughly an additional
16,000 specific materials licensees.
Radioactive material is present at USNRC-licensed facilities in containment
buildings; vehicles such as trucks and forklifts; and tools, piping, ductwork, or
any other part of an object within a nuclear facility that has come into contact
with radionuclides during normal operations or decommissioning. Surface con-
tamination occurs when radioactive material remains on the surface of an other-
wise uncontaminated object. Unlike volume contamination, it is sometimes eas-
ily removed using chemical or mechanical methods. Volume contamination
occurs in a variety of ways, such as when radioactive material penetrates via
cracks, pores, grain boundaries, or solid-state diffusion into an object or when
incident neutrons activate (make radioactive) some of the atoms within an object.
Volume contamination can also arise through mixing of radioactive material with
solids such as soil. Objects having volume contamination are generally more
difficult to decontaminate and are subject to a less-well-articulated system of
standards for clearance from further regulatory control, as discussed below. The
radiation emitted by radioactive material can have detrimental health effects on
the various organs and tissues of the body, including induction of cancer. The
unit of dose equivalent in the international system (SI), the sievert (Sv; equal to
100 rem) is used to indicate the biological effect of ionizing radiation and is used
in setting radiation protection standards.
In conducting its study, the committee first examined the current system of
standards, guidance, and practices used by the USNRC and agreement states to
determine whether to release slightly radioactive solid material from further regu-
latory control under the Atomic Energy Act. The committee found that the cur-
rent, workable system allows licensees to release material according to preestab-
lished criteria but contains inconsistencies such that nuclear reactor licensees can
release materials only if there is no detectable radioactivity4 (above background
levels), whereas materials licensees can do so if small detectable levels are found.
The USNRC uses a guidance document for this latter purpose, Regulatory Guide
3section 274 of the Atomic Energy Act (AEA) authorizes the commission to enter into an effec-
tive agreement with the governor of a state to allow that state to assume the USNRC,s authority to
regulate certain types of materials licensees only. Reactor licensees remain the exclusive domain of
the USNRC. Today there are 32 agreement states, which have implemented regulatory programs that
are compatible with the USNRC,s programs. The materials licensees that a state can regulate include
those that use or possess source material, byproduct material, or special nuclear material in quantities
not sufficient to form a critical mass (e.g., less than 350 grams of uranium-235).
4Reactor licensees can, however, apply to USNRC for approval to release solid materials with
small but detectable levels of radioactivity pursuant to section 2002 of 10 CFR Part 20.
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4
THE DISPOSITION DILEMMA
1.86, which includes a table of surface contamination limits that are technology
based (measurement based) and not risk based (dose based). These limits are
typically incorporated as license conditions or technical specifications in the case
of materials licensees and subsequently used by the licensee to release material,
whereas, as noted above, reactor licensees cannot release material if radioactivity
is detected above natural background. No table of limits exists for volume con-
tamination. Instead, the USNRC and its agreement states decide on a case-by-
case basis whether release of volume-contaminated solid materials can occur.
The committee found that licensees are currently submitting case-by-case appli-
cations at a rate that is being adequately managed by the USNRC and the agree-
ment states.
Materials with levels of radioactivity not detectable above background radia-
tion (with routine radiation measurements) are being released on a daily basis
from nuclear power plants under a licensee arrangement with either the agree-
ment states or the USNRC. In addition, some materials with volume contamina-
tion are being released on a case-by-case basis. The amount of these materials is
not known, because there is no requirement to document the materials released.
The annual dose equivalent resulting from these releases on a case-by-case basis
has been estimated in draft NUREG-1640 at 10 ,uSv/yr (1 mrem/yr) or less for
most of the radionuclides of interest.
The committee found that in future years the vast majority of slightly radio-
active solid materials subject to the USNRC's system of clearance standards and
practices will come from closing (decommissioning) nuclear power plants. Metal
and concrete will constitute the greatest volume of slightly radioactive solid
materials resulting from decommissioning. If power reactors are decommissioned
on the schedule set by their current licenses, large quantities of metal and con-
crete waste will be generated during the next several decades, as shown in Figure
ES-1. If licenses are extended for an additional 20 years, which seems probable
for most facilities, the schedule shown in Figure ES-1 would be set back by as
much as 20 years, with little material generated from decommissioning until after
2030.
The committee considered three general categories of options for disposition
of slightly radioactive solid materials. Clearances (unconditional i.e., unre-
stricted release) means that the material is handled as if it is no longer radioac-
tive. Under this option, solid material (e.g., a tool) can be reused without restric-
tion, recycled into a consumer product (e.g., a patio table), or disposed of in a
landfill. (Classification of the waste as hazardous, for example, under the Re-
source Conservation and Recovery Act [RCRA], would depend on its other prop-
erties.) The committee found only limited support for clearance that allows
5Where the term clearance (i.e., no longer under regulatory control) appears, it is understood to
mean unconditional clearance.
OCR for page 5
EXECUTIVE SUMMARY
1, 200, 000 -
1, 000, 000
800, 000
600, 000
400, 000
200, 000
~ Concrete 1
111~ Metals
...................... I I T T T T T r r r T T T ~ ~ T T T T T r r r r r T T T
~3~ ~3> ~3~ ~~ ~~ ~~ ~~>
Year
FIGURE ES-1 Time distribution for generation of slightly radioactive solid material from
U.S. power reactor decommissionings. SOURCE: Adapted from SCA (2001~.
s
slightly radioactive solid materials to enter commerce for unrestricted recycled
use, no matter how restrictive the clearance standard might be. No support for this
option exists in the steel and concrete industries.
Conditional clearance (i.e., restricted release from regulatory control) means
that material must be used in a specified application and subject to continuing
regulatory control until specific conditions are met. For example, slightly radio-
active metal released under a conditional clearance standard might be melted into
shielding blocks for use at DOE nuclear facilities but could be subject to controls
in the process. Other examples might include slightly radioactive concrete that
must be disposed of in a Subtitle D landfill or concrete that is released for use in
the rubble base for roads. Conditionally cleared material would not be released
for use in general commerce.
No release (from regulatory control) means that the slightly radioactive solid
material, once it leaves the originating facility, must be sent to a facility licensed
to accept radioactive solid material for storage or disposal. Under this option, the
slightly radioactive solid material remains under a USNRC or agreement state
license continuously.6 Under current conditions, slightly radioactive solid mate-
rial would be sent to either Envirocare of Utah or one of two disposal facilities
licensed to accept all types of low-level radioactive waste (LLRW) Barnwell,
6Until the expiration of postclosure monitoring requirements.
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6
THE DISPOSITION DILEMMA
South Carolina, or U.S. Ecology in Richland, Washington in accordance with
each facility's licenses and permits. Each general disposition option clearance,
conditional clearance, and no release has minor variants and regulatory com-
plexities, which are discussed in this report.
Each disposition option has economic implications due to associated pricing
and handling, regulation, and disposal. (For estimation purposes, only concrete
and metal are considered.) If the material is disposed of as radioactive waste, as in
the case of "no release," then the disposal fee charged by the facility could range
from $3,120 (U.S. Ecology) to $16,800 (Barnwell) per cubic meter in the two
licensed commercial low-level radioactive waste disposal facilities. The cost to
dispose of slightly radioactive metal from all U.S. power reactors would range
from $1.6 billion to $8.8 billion, depending on whether U.S. Ecology or Barnwell
is used, respectively.7 For slightly radioactive concrete, the committee estimates
disposal at Envirocare of Utah could be accomplished at a cost roughly one
eighth that of U.S. Ecology, giving a total cost for all concrete from U.S. power
reactors of $2.9 billion.8 The total cost to dispose of all slightly radioactive solid
material metal and concrete from U.S. power reactors under the no-release
option is thus estimated at between $4.5 billion and $11.7 billion. Less costly
disposal is possible if the slightly radioactive solid material meets the terms of
conditional clearance and can be sent to a landfill. Then disposal can be accom-
plished at a disposal fee of approximately $30 per metric ton for a Subtitle D
landfill (municipal waste) and approximately $110 per metric ton for a RCRA
Subtitle C landfill (hazardous waste). Disposal of all the slightly radioactive solid
material anticipated from U.S. power reactors could cost $0.3 billion in Subtitle
D landfills and $1 billion in Subtitle C landfills. Clearance of all this material
could allow the option of recycle or reuse for some of the material, as appropriate,
and would avoid essentially all disposal costs. These estimates are shown to
illustrate the relative costs of the different clearance policy options; it should be
emphasized, however, that the cost of disposal of slightly radioactive solid mate-
rials may in the future be subject to factors that the committee is not able to
foresee or take into account. For example, the committee has not considered
energy deregulation or the impact on ratepayers caused by any changes that may
be made to clearance rules.
Licensees will base decisions on which disposition option is appropriate for
7Envirocare of Utah is licensed to accept bulk metal for disposal but does not publish pricing
information and determines prices on a case-by-case basis. The committee was not able to find data
on such prices for disposal of bulk metals at Envirocare, so it has not estimated the costs of disposal
Of metal from u.s. power reactors.
8Envirocare of Utah charges the u.s. Army corps of Engineers $298 per cubic yard ($388 per
cubic meter) for disposal of high-volume, slightly radioactive concrete debris, which is classified as
pre-1978 uranium mill tailings by the USNRC.
OCR for page 7
EXECUTIVE SUMMARY
7
a particular quantity of slightly radioactive solid material, in part, on measure-
ments of the amounts of radioactive materials present. Measurement of the amount
of radioactive material in a solid matrix is a function of instrument characteris-
tics, background radiation levels, and source characteristics. If the sampling and
analysis costs are too high, it may be more cost-effective to dispose of the mate-
rial at a facility licensed to accept low-level radioactive waste rather than demon-
strate compliance with a clearance standard to allow landfill disposal. For screen-
ing-level concentrations and surface contaminations calculated from dose levels
greater than or equal to 10 ,uSv/yr (1 mrem/yr), for a defined exposure scenario,
detection is possible in a laboratory setting for a majority of radionuclides under
most practical conditions at reasonable costs. Using field measurements, a more
rapid fall-off of detectability is observed at more stringent radiation protection
levels, with 31 of 40 key radionuclides detectable at 10 ,uSv/yr (1 mrem/yr) and
11 of 40 detectable at 1 ,uSv/yr (0.1 mrem/yr).
The committee evaluated technical analyses of the estimated doses of the
final disposition of slightly radioactive solid materials. These analyses were con-
ducted by federal agencies and international organizations, including the Interna-
tional Atomic Energy Agency (IAEA), the European Commission, and other
groups. The committee paid particular attention to a draft USNRC document,
NUREG-1640, which was developed to support its most recent evaluation of the
clearance standard issue. The committee concluded that of the various reports
considered, draft NUREG-1640 provided a conceptualframework, particularly
with regard to incorporating formal uncertainty, that best represents the current
state of the art in risk assessment. The committee did find limitations in the
report, including its lack of applicability to scenarios of conditional clearance
(e.g., landfill disposal), lack of consideration of multiple exposure pathways, and
lack of consideration of human error9 and its possible effect on dose factor
prediction. Draft NUREG-1640 has also been clouded by questions of contractor
conflict of interest.
To determine if numerical values in the report had been affected by consid-
erations other than science, the committee checked a sample of dose factor analy-
ses and found them reasonable. Once all of the dose factors are checked as the
committee recommends and other limitations in draft NUREG-1640 have been
resolved either in the final version of the report or in follow-up reports the
resulting dose factors can be multiplied by appropriate dose-risk coefficients to
provide estimates of the risks of releasing individual radionuclides at any hypo-
thetical concentration. The USNRC will then have a sound basis for considering
9Human error is used here to mean the violation of scenario assumptions at some infrequent, but
nonzero, rate. categories of relevant human error include mistakes in properly labeling material,
mistakes in measurement, or failure to properly decontaminate loose material as assumed in dose
factor estimates.
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8
THE DISPOSITION DILEMMA
the total risks associated with any proposed clearance standards and for assessing
the uncertainty attached to dose estimates. The committee does not believe it is
necessary from a scientific perspective for the USNRC to start all over again.
The committee reviewed efforts by other countries and international organi-
zations to set clearance standards. The European Union has issued a safety direc-
OCR for page 9
EXECUTIVE SUMMARY
9
five containing tables derived using a scenario assessment process against which
slightly radioactive solid materials can be evaluated for possible clearance from
further regulatory control. Member nations of the European Union are in the
process of implementing this directive.
The issue of releasing radioactive materials from further regulatory control,
like the issue of nuclear power in general, has received significant stakeholder
input. The committee found that in the past, the USNRC failed to convince any
environmental and consumer advocacy groups that the clearance of slightly ra-
dioactive solid material can be conducted safely and failed to convince certain
industry groups that such clearance is desirable. Most of the issues and concerns
expressed today by many consumer advocacy and environmental groups and
some industry groups are the same as were expressed during the controversy over
the BRC policy in 1990. Furthermore, a legacy of distrust of the USNRC has
developed among many of the environmental stakeholder groups, resulting from
their experience with the BRC policy, the enhanced participatory rulemaking on
license termination ("decommissioning rule"), and the USNRC's 1999 issues
paper, published in the Federal Register on June 30, 1999, on the clearance
standards. Reestablishing trust will require concerted and sustained effort by the
USNRC.
The committee developed a series of policy alternatives to the current sys-
tem, detailed in Box ES-1. The committee found that there is time for the USNRC
to move forward and select from among the alternatives, since no evidence was
found that the problems associated with the current case-by-case approach re-
quired its immediate replacement. The committee does not recommend any one
particular alternative. Instead, it emphasizes the need for the USNRC to under-
take with deliberate speed and a broad range of stakeholder involvement a de-
tailed and thorough analysis and evaluation of various alternative approaches that
proceeds from logical starting points based on a sound technical foundation.
Should the USNRC choose to develop new regulations for clearance, it has to
consider that any action it takes may have implications for the management of
materials e.g., technologically enhanced naturally occurring radioactive mate-
rials (TENORM) that are not currently regulated by the USNRC, DOE, or
agreement states.
Considerations include effects on public health, costs and benefits, consis-
tency with existing national and international analysis, practice and legal author-
ity, and public perceptions and acceptance.
RECOMMENDATIONS
In developing its recommendations the committee was guided by two
overarching, compelling findings:
OCR for page 10
10
THE DISPOSITION DILEMMA
1. The current approach to clearance decisions is workable and is suffi-
ciently protective of public health that it does not need immediate re-
vamping. However, the current approach, among other shortcomings, is
inconsistently applied, is not explicitly risk based, and has no specific
standards in guidance or regulations for clearance of volume-contami-
nated slightly radioactive solid material. Therefore, the committee be-
lieves that the USNRC should move ahead without delay and start a
process of evaluating alternatives to the current system and its shortcom-
~ngs.
2. Broad stakeholder involvement and participation in the USNRC's deci-
sion-making process on the range of alternative approaches is critical as
the USNRC moves forward. The likelihood of acceptance of a USNRC
decision greatly increases when the process (1) engages all responsible
stakeholder representatives and viewpoints, (2) is perceived by partici-
pants as fair and open, (3) addresses all the advantages and disadvantages
of the alternative approaches in an even-handed way, and (4) is open to a
broad and creative range of alternatives. Thus, it is essential that the
USNRC focus on the process and not prescribe an outcome. The outcome,
an approach to disposition of slightly radioactive solid material, must
evolve from the process.
While the committee did not want to prescribe the outcome of the decision
process, it has made several specific recommendations, conditional on the pro-
cess arriving at certain decision points. For example, if the USNRC contemplates
clearance or conditional clearance standards, the committee recommends that
these standards be dose based. The committee also recognized that significant
national and international efforts have been completed, or are near completion,
that provide a solid foundation for the USNRC to move forward. The committee
has recommended the foundation from which to begin the process. Thus, the
USNRC should be able to proceed expeditiously with a broad-based stakeholder
participatory decision-making process.
Recommendation 1. The USNRC should devise a new decision framework that
would develop, analyze, and evaluate a broader range of alternative approaches
to the disposition of slightly radioactive solid material. At a minimum, these
alternatives should include the current case-by-case approach, clearance, condi-
tional clearance, and no release.
Recommendation 2. The USNRC's decision-making process on the range of
alternative approaches to the disposition of slightly radioactive solid material
should be integrated with a broad-based stakeholder participatory decision-mak-
ing process. Elements of this process should include the following:
OCR for page 11
EXECUTIVE SUMMARY
.
.
11
· The willingness and commitment of the USNRC to establish and maintain
a meaningful and open dialogue with a wide range of stakeholders regard-
ing the disposition of slightly radioactive solid material;
An ad hoc broad-based advisory board that would advise the USNRC in
its consideration of approaches to the disposition of slightly radioactive
solid material. The advisory board would also suggest additional stake-
holder involvement mechanisms that the USNRC could use in the deci-
sion process (for example, establishing a National Environmental Policy
Act process; alternative dispute resolution; and partnering, arbitration,
mediation, or a combination of such methods); and
Assistance obtained by the USNRC as needed from outside experts in
order to (1) assist its efforts to establish the ad hoc stakeholder advisory
board and to facilitate dialogue between the USNRC and stakeholder
participants in the decision-making process and (2) assess, evaluate, and
perhaps conduct portions of the USNRC stakeholder involvement pro-
gram and make recommendations as appropriate.
Recommendation 3. The USNRC should adopt an overarching policy statement
describing the principles governing the management and disposition of slightly
radioactive solid material. A review and discussion of the IAEA policy statement
Principles for the Exemption of Radiation Sources and Practices from Regula-
tory Control (Safety Series No. 89, IAEA Safety Guidelines, Vienna, 1988) with
a broad-based stakeholder group would provide a good starting point in develop-
ing a policy statement that would provide a foundation for evaluation of alterna-
tive approaches to disposition of slightly radioactive solid material.
Recommendation 4. When considering either clearance or conditional clear-
ance, a dose-based standard should be employed as the primary standard. To
employ a dose-based standard, it is necessary to consider a wide range of sce-
narios that encompass the people likely to be exposed to slightly radioactive solid
material. From these people, a critical group is selected and secondary standards
(based on dose factors) are derived. These secondary standards are used to limit
the radioactivity in materials being considered for release or conditional release.
The USNRC should also consider the pros and cons of the establishment of
a separate collective dose standard.
Recommendation 5. An individual dose standard of 10 ,uSv/yr (1 mrem/yr)
provides a reasonable starting point for the process of considering options for a
dose-based standard for clearance or conditional clearance of slightly radioactive
solid material. This starting point is appropriate for the following reasons:
.
A dose of 10 ,uSv/yr (1 mrem/yr) is a small fraction (less than 0.5 percent)
of the radiation received each year from natural background sources.
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2
THE DISPOSITION DILEMMA
.
.
A dose of 10 ,uSv/yr (1 mremlyr) is significantly less than the amount of
radiation that we receive from our own body due to radioactive potassium
(one contributor to background radiation) and other elements and to rou-
tine medical procedures that involve ionizing radiation.
A dose of 10 ,uSv/yr (1 mrem/yr) over a 70-year lifetime equates to an
estimated increase of 3.5 x 10-5 in the lifetime cancer risk, which falls
within the range of acceptable lifetime risks of 5 x 10= to 10-6 used in
developing health-based standards for exposure to radiation (other than
for radon) in the United States.
· Radiation measurement technologies are available at a reasonable cost to
detect radioactivity at concentrations derived from this dose standard.
· This dose standard is widely accepted by recognized national and interna-
tional organizations.
The final selection of an individual dose standard should nonetheless be a
policy choice, albeit one informed by the above considerations.
Recommendation 6. For any dose-based alternative approach to disposition of
slightly radioactive solid materials, the USNRC should use the conceptualframe-
work of draft NUREG-1640 to assess dose implications. To use the actual results
of NUREG-1640 in the decision framework discussed in Recommendations 1
and 2, the USNRC must first establish confidence in the numerical values, ex-
pand the scope of applicability, and overcome certain limitations in draft NUREG-
1640. At a minimum, the following specific actions are required:
.
.
Review the choice of parameter distributions used in the dose modeling,
as well as the characteristic values chosen for each parameter distribution.
· Develop complete scenarios and dose factors for conditional clearance
options.
· Provide sufficient information to enable calculation of collective doses to
support Recommendation 4.
Expand the current set of scenarios used to compute dose factors to in-
clude (1) human error and (2) multiple exposure pathways.
The USNRC should use an independent group of experts to provide peer review
of these activities.
Recommendation 7. The USNRC should continue to review, assess, and partici-
pate in the ongoing international effort to manage the disposition of slightly
radioactive solid material. The USNRC should also develop a rationale for con-
sistency between secondary dose standards that may be adopted by the United
States and other countries. However, the USNRC should ensure that the technical
basis for secondary dose standards is not adjusted for consistency unless these
adjustments are supported by scientific evidence.
Representative terms from entire chapter:
radioactive solid