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Nuclear
Material Control and Accountability:
DOE M 470.4-6, Nuclear Material Control
and Accountability, was issued on August
26, 2005, and page changes were issued to
that manual as Change 1 on August 8, 2006.
The most frequently asked questions concern
credible roll-up and tritium, which are
answered briefly below.
Q: What are Technical Standards?
A: Technical standards are developed and adopted by voluntary consensus
standards bodies as a means to carry out policy objectives
or activities as determined by the agencies and departments.
Q: Why are we making a technical standard for MC&A?
A: This technical standard on Nuclear Material Control and Accountability
(MC&A) is being developed to provide site facilities with
an accepted means of meeting the performance objectives and
metrics specified in the policy requirements for MC&A.
Q: What is the purpose of an MC&A
plan?
A: MC&A plans can serve as a planning document for the facility
to use in carrying out its MC&A program and budgeting
for its operations. Additionally, MC&A plans have
several purposes:
1) Providing documentation
to DOE/NNSA about how facilities will operate
their MC&A programs, MC&A plans
are required by DOE M 470.4-6, Nuclear Materials
Control and Accountability, for all facilities
possessing nuclear materials, and represent
commitments by the facility to DOE/NNSA
to operate their MC&A program as described
in the plans or to standards exceeding the
requirements of the plans. As such, facilities
can be audited or inspected by DOE offices
or programs against the plans;
2) Establishing specific
authorities and responsibilities for MC&A
functions (e.g. accounting systems, measurements,
measurement control, inventories, internal
reviews, access controls, and material surveillance.);
3) Describing local implementation
of DOE 470.4-6, at the facility, and how
facility MC&A programs meet the requirements
of that directive; and
4) Documenting facility
specific requirements approved by the DOE
cognizant security authority, including
but not limited to the scope and extent
of performance testing, measurement requirements
for internal transfers, parameters for statistical
sampling plans for physical inventories,
frequency and scope of internal reviews
of MC&A programs, and extensions to
inventory frequencies. Ideally, all locally
approved requirements will be addressed
in the MC&A plan.
Q: Who approves MC&A plans?
A: DOE M 470.4-6 requires that a specific DOE cognizant security
authority (which could be the site security director,
site manager or MC&A program manager depending on
formal delegation) be designated as the DOE approving
authority for MC&A plans, activities, and documents
- including the MC&A plan, but does not specify who
the approving authority should be. Program and site offices
decide at what level of their organization MC&A approval
authorities should reside based upon their resources and
management structure. More generally, DOE O 470.4A designates
the Departmental Under Secretaries as the overall cognizant
security authorities for their organizations, and allows
them to delegate those authorities to lower level DOE/NNSA
officials. The delegations of authority are required to
be in writing, and should be addressed in documents describing
program functions, responsibilities, and authorities.
Q: What are Reporting Identification
Symbols (RISs) and how are they used?
A: RISs are three or four letter codes assigned to DOE offices
and contractors that possess nuclear materials, as well
as NRC office and licensees that possess these materials.
RISs for DOE offices and contractors are assigned by the
Office of Information Management, HS-1.22. RISs for NRC
offices and Licensees are assigned by the NRC Office of
Nuclear Material Safety and Security. They are used for
reporting nuclear materials inventories and transactions
to the NMMSS. All DOE offices and contractors possessing
reportable quantities of nuclear materials are required
to have an RIS. They are also required to have a nuclear
materials representative (NMR) for the RIS; the NMR is
responsible for submitting site/facility data to NMMSS.
There is a rough correspondence between
DOE sites and RISs, but the correspondence
is not exact for several reasons: Different
RISs are required for each DOE contractor
possessing nuclear materials, and sites
can have more than one contractor that possesses
materials. Different RISs are used for waste
areas than for processing and storage areas
on the same site. Materials under the International
Atomic Energy Agency (IAEA) are reported
to NMMSS using a different RIS from other
site RISs. Many DOE site offices have their
own RIS separate from contractor RISs. For
these reasons, most major DOE sites have
more than one RIS. Additionally, some offsite
materials may be included in the DOE office's
or contractor's RIS.
Q: What nuclear materials does DOE
M 470.4-6 address?
A: These nuclear materials include: Americium-241, americium-243,
berkelium, californium-252, curium, deuterium, depleted
uranium, normal uranium, enriched uranium, uranium-233,
enriched lithium, plutonium, neptunium-237, thorium, and
tritium.
DOE M 470.4-6 focuses on plutonium, enriched
uranium, uranium-233, separated americium,
and separated neptunium-237, because of
their proliferation potential, but requires
MC&A programs for all these materials.
Plutonium, enriched uranium, and uranium-233
are defined or designated as special nuclear
material (SNM) by the Atomic Energy Act
of 1954 and have long been considered material
of concern for nuclear proliferation. More
recently the International Atomic Energy
Agency recommended that separated americium
and separated neptunium-237 be treated the
same as SNM for safeguards purposes, and
DOE has adopted this recommendation into
its regulations.
Q: What are the MC&A requirements
for non-SNM?
A: Requirements for tritium, separated americium, and separated
neptunium, are based on those for SNM. Requirements and
graded safeguards thresholds for separated neptunium-237
and separated americium are identical to those for U-235.
Tritium is treated as either Category III or IV SNM depending
on its form, quantity, and isotopic purity.
MC&A requirements for non-SNM materials
other than tritium, separated neptunium-237,
and separated americium, are largely at
the discretion of the DOE cognizant security
authority responsible for MC&A. The
only specific requirements are that
1) An MC&A program be
established and maintained for these materials
based on the strategic and monetary value
of the materials.
2) The data fields for the
materials accounting system for these materials
be consistent with those required by DOE
M 470.4-6.
3) Reporting Identification
Symbol (RIS) level transactions and inventories
be documented by the system and reported
to the Nuclear Materials Management and
Safeguards System (NMMSS) in accordance
with DOE M 470.4-6, Section B. (Berkelium
is not required to be reported to NMMSS
because the total amount DOE owns is very
small, it has a short half-life, and it
has been written off DOE's financial records
by the Office of Financial Management.)
4) Physical inventories
of these materials be conducted on a periodic
basis at a frequency and in a manner approved
by the DOE cognizant security authority
and documented in the MC&A plan.
5) Materials that are collocated
with SNM and are credible substitution materials
for the SNM be inventoried at the same frequency
as the SNM and measurement methods used
for inventories are capable of distinguishing
between the SNM and the collocated materials.
Q: Are DOE-owned nuclear materials at
NRC licensee facilities reported to NMMSS
under DOE requirements or NRC requirements?
A: They are reported using DOE requirements. This is based on
an agreement between DOE and NRC and is reflected in NRC
regulatory documents NUREG/BR-0006, Instructions for
Completing Nuclear Material Transaction Reports, and
NUREG/BR-0007, Instructions for the Preparation and
Distribution of Material Status Reports. Additionally,
the requirement to report pursuant to DOE instructions
is usually reflected in contract and lease agreements
for use of DOE-owned materials by NRC licensees.
Q: What does the term "credible
roll-up" mean with regard to MC&A?
A: Roll-up is the accumulation to
a higher safeguards category of special
nuclear material (SNM) from lower category
locations. Roll-up is credible if the materials
can be accumulated and removed from the
site prior to interruption and defeat by
site personnel, including protective forces.
Q: I'm confused by tritium "reportable
quantity" vs. "reporting unit."
Table I-2 of Section A of DOE M 470.4-6,
Chg 1, lists the "reportable quantity"
for tritium as 1 gram, but Table XV-1 of
Section B of same manual lists the "reporting
unit" for tritium as 1/100 of a gram.
Why are these two quantities different?
A: Reporting unit and reportable
quantity are different concepts. Reporting
unit is the mass unit that facility/site
nuclear material accounting systems use
for recording and reporting inventories
and transactions. Reportable quantity is
the minimum amount of a material that a
facility must have to be subject to requirements
of DOE M 470.4-6 for that material. Except
for tritium, the reporting units and reportable
quantity for nuclear materials are same.
Historically, a hundredth of a gram was
both the reporting unit and the reportable
quantity for tritium. In 2003, the reportable
quantity of tritium was changed to a gram
in order to exempt facilities with less
than that amount (primarily research facilities)
from the MC&A requirements for tritium.
The reporting unit was being maintained
at 1/100 of a gram at the request of our
larger tritium facilities and to maintain
compatibility with historical MC&A record-keeping
systems. Facilities with more than a gram
of tritium are still required to report
transactions of 1/100 of gram or more.
Q: On December 3, 2007, the DOE Chief Health, Safety and
Security Officer signed out a memorandum establishing policy
panels to increase feedback from the implementers of DOE policy.
How will the MC&A policy panel be organized?
A: The MC&A policy panel will be a continuation of
the current MC&A quality panel with emphasis on creating new
opportunities for communications between the HS-71 MC&A policy
development team and end users of MC&A policy. Face-to-face
meetings will be organized similarly to current quality panel
meetings, but there will be greater use of alternative means
of conducting meetings. The goals of the panel include identification
of MC&A policy issues and increasing the effectiveness of
the MC&A policy development process. The results of all teleconferences
and meetings will be compiled and appropriately distributed.
The policy panel's activities will be centrally monitored
to assure continued relevance and utility.
Q: What is a material balance?
A: A material balance is a calculation evaluating
the physical inventory of nuclear material actually present
in an area or a facility using beginning and ending inventories
after considering transfers of nuclear material into and out
of the area or facility. The material balance results in a
quantity called the inventory difference (ID) which is defined
by the following equation, commonly known as the material
balance equation:
ID = BI + A - R - EI
(BI=beginning inventory; EI=ending physical inventory; A=additions to inventory; R=removal from inventory.)
For material in process, a non-zero ID is expected because of measurement uncertainties
and the nature of processing. For items in storage, a non-zero ID indicates that either
material is missing or an item has been misplaced.
Q: What is a material balance area (MBA)?
A: An MBA is both a subsidiary account of the nuclear
materials account for a facility and a geographical-bounded
location within the facility. MBAs are used to localize nuclear
material losses by subdividing the facility nuclear materials
account into smaller units and restricting material in these
accounts to specific geographically-bounded locations and
processes within the facility. Establishing MBAs within the
facility allows operations and safeguards personnel to maintain
a better idea of the types and quantities of materials present
at various locations in the facility and enhances internal
control of the materials by establishing where within a facility
various types and forms of materials are authorized to be.
It also allows for administrative controls to be put in place
to govern movement of materials between authorized areas of
the facility and for materials balances to be closed around
areas smaller than the facility as whole.
MBAs should be defined as geographical areas with defined physical boundaries and under
the control of one person, the MBA custodian, for MC&A purposes. Additionally, transfers
between MBAs should be based on measured values, and ideally, MBA boundaries will not cross
security area boundaries. In fact, DOE M 470.4-6, Chg1, Nuclear Material Control and
Accountability, requires that MBA boundaries not cross material access areas (MAAs) boundaries.
Q: What is the role of ANSI/ASTM Technical standards in
DOE MC&A programs?
A: Public Law (P.L.) 104-113, the National Technology
and Transfer and Advancement Act of 1995, requires that
all Federal agencies and department use technical standards
developed and adopted by voluntary consensus standards bodies
as a means to carry out policy objectives or activities as
determined by the agencies and departments. The act further
states that Federal agencies and departments shall consult
with voluntary, private sector, consensus standards bodies,
and shall participate with such bodies in the development
of technical standards. A copy of P.L. 104-113 can be found
at www.gpoaccess.gov/plaws/104publ.html.
Consistent with P. L. 104-113, DOE M 470.4-6, Chg 1, Nuclear Material Control and
Accountability requires that DOE line management assure that technical standards developed or
adopted by voluntary consensus standards bodies, such as the American National Standards Institute (ANSI)
and the American Society for Testing and Materials (ASTM) International, are considered in development
of MC&A programs under their cognizance. The primary ANSI and ASTM standards of interest to MC&A
address measurements, measurement control programs, and SNM portal monitors. Standards addressing
these topics are listed in DOE M 470.4-7, Safeguards and Security Program References.
Q: What is graded safeguards for MC&A?
A: Graded safeguards is the concept of providing the
greatest relative control, accountability, and protection
for the types, quantities, and forms of special nuclear materials
that can be most effectively used in a nuclear device or easily
converted to such materials. The level of control and protection
required is based on safeguards categories and attractiveness
levels of the materials, which are described below.
Q: What are MC&A safeguards attractiveness levels?
A: MC&A safeguards attractiveness levels are a ranking
of various types and forms of special nuclear materials based
on their usefulness in constructing a nuclear weapon or an
improvised nuclear device (IND). Generally, the attractiveness
of particular physical form is based on two factors (1) the
relative ease of either directly using the material in an
IND or converting it to a usable form, and (2) any self-protecting
properties of the material, such as high levels or radioactivity,
that make the material more difficult to handle or process.
Attractiveness levels range from "A" to "E," with A being
the most attractive and E being the least attractive. Attractiveness
level A includes nuclear weapons and test devices. Attractiveness
level B consists of pure products (metal and directly convertible
material). Attractiveness level C consists of high grade materials
that can easily be converted into B materials. Attractiveness
level D consists of materials that require greater processing
time and complexity to convert to B materials. Attractiveness
level E contains other materials not covered by attractiveness
levels A through D, such as highly irradiated materials, low-enriched
uranium, and highly dilute materials (e.g. solutions less
than 1gram per liter).
The Office of Health, Safety and Security in conjunction with NNSA and the weapons
laboratories are in the process of reviewing the current attractiveness levels to determine
if they need to be updated to address changing technical capabilities and/or to eliminate
ambiguities. Possible policy changes based upon this technical review are under HSS review.
Q: What are MC&A safeguards categories?
A: MC&A Safeguard's categories are designations used
for ranking of MBAs, facilities, special nuclear material
(SNM) items, and other collections of materials in terms of
required levels of protection, control, and accounting. Safeguards
categories are based on both the amounts of material present
and the safeguards attractiveness levels of the materials.
Safeguards categories range from Category I to Category IV,
with Category I requiring the highest level of protection
and Category IV the lowest. MC&A and physical protection requirements
for facilities, MBAs, and other collection of materials are
based primarily on the safeguards category of the material.
In addition to attractiveness level and quantities of material
present, safeguards categories also depend on material type
(i.e., whether the material is plutonium, uranium enriched
in the isotope 235, or uranium enriched in the isotope 233).
For example, 2 kilograms of plutonium metal would be Category
I quantity, but the same amount of uranium-235 contained in
highly enriched uranium metal would only be a Category II
quantity. The upper and lower safeguards category threshold
quantities for the various material types and attractiveness
are defined in Table 1-4, Graded Safeguards, DOE M 470.4-6,
Chg1, Nuclear Material Control and Accountability,
along with additional instructions for determining safeguards
categories.
HSS, in conjunction with NNSA and the weapons laboratories, is in the process of reviewing
the current safeguards categories to determine if changes need to be made based on evolving
technical capabilities and the need for consistency with policy documents of other agencies.
Possible policy changes based upon this technical review are under HSS review.
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This page was last updated on November 06, 2009
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