ST ATE OF NEW MEXICO ENVIRONMENT DEPARTMENT
IN THE MATTER OF THE RENEWED ) HAZARDOUS WASTE FACILITY ) PERMIT FOR THE WASTE ISOLATION) PILOT PLANT )
) HWB 10-26(P)
WRITTEN TESTIMONY OF CONSTANCE WALKER
My name is Constance Walker. I am an environmental consultant employed by Trinity
Engineering Associates. I am presenting this written testimony on behalf of the New Mexico
Environment Department in the hearing concerning the issuance of a renewal permit for
management, storage and disposal of hazardous waste, and the closure of hazardous waste
disposal units, at the Waste Isolation Pilot Plant (WIPP). The proposed hazardous waste facility
permit for WIPP, dated July 2, 2010 (Proposed Permit), is marked as NMED Exhibit 1. This
testimony is marked as NMED Exhibit 9.
I. QUALIFICATIONS
I hold a Bachelor of Science degree in geology with a minor in physical anthropology
from Colorado State University, where I graduated Phi Beta Kappa. I hold a Master of Science
degree in geology from the Colorado School of Mines.
I have provided RCRA Subtitle C support to the Department with respect to WIPP,
beginning with the Test Phase and Disposal Phase Subpart X Part B Permit application reviews. I
reviewed hundreds of WIPP-related technical documents in the areas of geology, hydrology,
environmental monitoring (i. e. groundwater), waste characterization, TRU-mixed waste, and
engineering. I managed and performed permit application assessment, with an emphasis on
waste characterization, and helped write the Draft Disposal Phase Permit. I provided oral and
EXHIBIT
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written expert testimony at the hearing in the areas of waste characterization, general and WIPP
specific audit procedures, TRU mixed waste, and waste management procedures. Following
issuance of the permit, I participated in dozens of waste characterization audits as an audit
observer, and I have reviewed several permit modification requests and other WIPP technical
documents.
I have attended dozens of WIPP generator/storage site audits on behalf of NMED, and
have observed the waste characterization processes at nearly every waste generation site in the
waste characterization program, including audits performed to evaluate characterization
processes for both contact-handled and remote-handled waste. I have reviewed audit reports for
each of the sites and am technically knowledgeable in areas subject to the audit program with an
emphasis on Acceptable Knowledge. I have coordinated contractor efforts for all of the
contractor-supported Department audit observations, assigning staff and participating in audits
themselves.
I have also performed consulting work concerning WIPP for the Environmental
Protection Agency's Office of Radiation and Indoor Air (EPA ORlA). I served as both the
Deputy Program Manager (1995-2000) and Program Manager (2000-2004) on WIPP oversight
technical support contracts, managing and participating in work assignments dealing with the
WIPP Compliance Certification Application (CCA) review and support activities. I currently
support the EPA's WIPP program by providing waste characterization expertise including waste
inspection performance, Tier 1 and Tier 2 request analyses, and technical document review and
analysis. In connection with review of the CCA, I personally performed technical analysis in the
areas of waste characterization, geology, hydrology, waste acceptance criteria, environmental
monitoring, and human intrusion scenario analyses, and reviewed engineering analysis of
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shaft/panel seal design. On behalf of EPA, I have performed numerous WIPP Waste Generator
Inspections to assess compliance with commitments set forth in the CCA and subsequent 2004
and 2009 Compliance Recertification Applications.
I currently serve as the Acceptable Knowledge Expert for both the Department and EPA.
Specifically, I am skilled in the areas of general audit and inspection procedures, review of audit
and inspection-related documents, evaluation of audit and inspection-related reports and
associated sampling/analysis plans and analytical results. I am also well versed with
compliance-related requirements presented in documents such as the TRU WAC, Rev. 6.5,
Permit Waste Analysis Plan, and the WIPP Waste Characterization Program Implementation
Plan for RH waste, which documents DOE's 40 CFR 194.24 compliance strategy for RH waste.
My testimony today concerns two matters: (1) the Department's revision of the
definition of "waste stream" and (2) the new language concerning the use of Acceptable
Knowledge in waste characterization.
1. Revised definition of "waste stream"
A revised definition of "waste stream" is contained in the Proposed Permit. As
background, waste characterization under the Current Permit and the Proposed Permit is carried
out on a waste stream basis. That is, characterization efforts are planned and carried out based
on waste stream information presented in a Waste Stream Profile Form (WSPF), with supporting
documentation, for approval by DOE. (See Permit Section C-Oc)
The Permit states that generator/storage sites shall delineate waste streams using
acceptable knowledge. (Permit Section C-l a) Certain permit provisions identify acceptable
knowledge that is required to be considered and "additional" acceptable knowledge. (Permit
Sections C-3b, C4-2a, C4-2b, C4-2c)
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Correct delineation of a waste stream is important, because examination of containers
(i.e., headspace gas, solid sampling, and radiography or visual examination) is conducted on a
waste stream basis. If the waste stream is correctly delineated, the examination of containers
will be performed efficiently. Also, assignment of correct hazardous waste numbers ensures that
only waste identified in Hazardous Waste Permit Application Part A (Attachment 0) are
accepted for disposal and that the waste is compatible in accordance with the Current Permit. In
addition, if waste streams are well defined, and an issue later arises with a stream that either
requires removal of drums from the subsurface or cessation of waste stream shipment, the
affected population would be correctly identified and managed, instead of a larger population if
the waste stream is delineated too broadly.
The existing Permit contains this definition of "waste stream":
"A waste stream is defined as waste material generated from a single process or from an
activity that is similar in material, physical form, and hazardous constituents." (Current
Permit Section B-Oa)
Generator/storage site waste characterization programs use this definition to delineate
populations of waste containers that are grouped together as a waste stream.
The Department has observed implementation of the current "waste stream" definition
through the Permittees' waste characterization audit program. I have attended six or more audits
each year for a period of ten years on behalf of the Department. I have observed that some sites
interpret the waste stream definition to require determination of the waste stream based on
specific processes (e.g., active facilities generating waste through specified process lines), while
other sites have interpreted the definition to mean that a waste stream may be defined by an
"activity" (e.g., building demolition). The requirement of commonality of material, physical
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form, and hazardous constituents has been implemented at different levels of detail and to
different extents.
In practice, the waste stream definition is sometimes too broadly interpreted. For
example, wastes from generalized processes are sometimes considered a single waste stream
without substantial consideration of the physical form, material, or hazardous constituents
associated with the waste stream. That is, the Permittees seem to interpret the current definition
as follows:
"A waste stream is defined as waste material generated:
(a) from a single process, or
(b) from an activity that is similar in material, physical form, and hazardous
constituents."
Such an interpretation conflicts with the Current Permit language, under which the requirement
of "similar[ity] in material, physical form, and hazardous constituents" applies to waste material
generated from either a "process" or an "activity." Further, the Permittees' reading is
unacceptable because an "activity" cannot be "similar in material, physical form, and hazardous
constituents." To clarify, the current definition should be understood as follows:
"A waste stream is defined as waste material
(a) generated from a single process or from an activity, and
(b) that is similar in material, physical form, and hazardous constituents."
During recent audits the definition of waste stream has required some scrutiny, because a
few waste streams are defined too broadly and the definition is not clearly and consistently
applied. For example, at the CCP Hanford Certification audit, a general Plutonium Finishing
Plant (PFP) demolition and decontamination waste stream was identified that included waste
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from various buildings. However, the source locations included Ancillary Facilities that, we
found, may be contaminated by waste from still other areas. After discussions, representatives of
CCP correctly modified the waste stream definition to exclude waste from these areas.
As necessary, NMED has posed questions at audits with respect to waste stream
determination. Based on our discussions, refinement and clarification of the meaning of the term
"waste stream" will prevent problems associated with application of the waste stream definition.
Thus, the Department has included this language in the Proposed Permit:
"A waste stream is defined as waste materials that have common physical form, that
contain similar hazardous constituents, and that are generated from a single process or
activity." (Permit Section C-Oa)
This definition recognizes that a waste stream is identified by a single process or activity, and the
waste materials in the stream must also have common physical form and similar chemical
characteristics. The key point is that the definition requires consideration of both the waste
generation activities (i.e., a single process or activity) and the physical and chemical
characteristics of the stream (common physical form, similar hazardous constituents) to delineate
a waste stream.
2. Acceptable knowledge in waste characterization:
Permit Attachment C4 describes how Acceptable Knowledge (AK) is gathered and used
in waste characterization. Modification of this section is proposed to clarify the application of
AK.
The Department has been concerned that some waste characterized by waste generator
sites as non-hazardous for purposes of storage or treatment has been subsequently assigned a
hazardous waste designation when prepared for shipment to WIPP. Similarly, waste to which
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sites had assigned certain hazardous waste numbers (HWNs) has, in characterization for
shipment to WIPP, received assignment of additional hazardous waste numbers that the site had
not previously applied. In response to such concerns, additional provisions appear in the
Proposed Permit that require sites to document how the waste was historically managed-mixed
(regulated) versus non-mixed (not regulated under RCRA)(Permit Section C4-2b). The
requirement to include this information in the auditable record ensures that this information will
be examined by those assigning hazardous waste numbers to the waste stream. Further, site
procedures must require that the combining ofTRU mixed and TRU non-mixed waste streams
into a single waste stream must be justified. (Permit Section C4-3b)
The Proposed Permit also revises language regarding assignment of HWNs. For
example, in the Current Permit, a site is required to " .. .include all sources of information in its
records and conservatively assign all potential hazardous waste numbers unless the sites choose
to justify an alternative assignment and document the justification in the auditable record."
(Current Permit Section B4-3b) The Proposed Permit states: "If discrepancies exist between
required information, then sites may consider applying all hazardous waste numbers indicated by
the information to the subject waste stream but must assess and evaluate the information to
determine the appropriate hazardous waste numbers consistent with RCRA requirements."
(Permit Section C4-2b) Thus, rather than imposing a conservative bias toward assignment of
HWNs, the Proposed Permit requires a site to " ... include all sources of information in its records
and [states that a site] may choose to either conservatively assign hazardous waste numbers or
assign only those numbers deemed appropriate and consistent with RCRA requirements."
(Permit Section C4-3b). Other new language requires that sites develop procedures that "ensure
the assignment of EP A hazardous waste numbers is appropriate, consistent with RCRA
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requirements, and considers site historical waste management." (Permit Section C4-2b). The
Permit Section addressing site procedures for assembly and compilation of AK has also been
revised to indicate that conservative assignment of HWNs is not mandatory. (Permit Section C4
3b). These modifications collectively modify the permit to allow hazardous waste number
assignments in accordance with RCRA rather than mandate a conservative assignment, noting
also that a conservative approach may be taken in accordance with RCRA.
In addition, language describing how "additional" AK information shall be employed and
recorded has been clarified and moved from the end of Permit Section C4-2c to the beginning.
The types of "additional" AK that may be used in characterization are expanded. (Permit
Section C4-2c).
This concludes my testimony.
I, Constance Walker, swear under penalty of perjury that the foregoing is true and correct.
L Constance Walker
nd sworn to before me this Etlilay of July, 2010 by Constance Walker
My commission expires:
CHERYL LLIBRA Notary PUblic
State Of COlorado
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