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					                                       Attachment 4
                            Second Technical Notice of Deficiency
                                     January 30, 2006

                                         Construction

Section 4.1
Describe the codes and standards which will apply to construction of the land disposal
facilities. [30 TAC '336.707(3)]
1. Comment: NUREG 1200 and NUREG/CR-5041both recommend using ACI 349, “Code
Requirements for Nuclear Safety Related Concrete Structures” and/or ANSI N45.2.5,
“Supplementary Quality Assurance Requirements for Installation, Inspection, and Testing of
Structural Concrete and Structural Steel During the Construction Phase of Nuclear Power
Plants” for requirements relating to concrete design, concrete specifications, concrete
construction, and quality assurance. The application instead uses ACI 318, “Building Code
Requirements for Structural Concrete and Commentary.”
Requested Action: In its TNOD1 response, the applicant did not use ACI 349, claiming that the
code and ACI 318 vary only by factors of safety. However, please note that ACI 349 also
comments on compatibility issues regarding reinforced concrete and radioactive materials.
Furthermore, the Applicant has stated that the “stringency” in ACI 349 is not needed because of
the supposed arid environment of the proposed trench. However, there is ongoing uncertainty of
the location of the water table at the site. Please apply ACI 349, as recommended by NUREGs,
to pertinent construction areas and reference the code in the application.
Response: NUREG-1200 and NUREG/CR-5041 criteria for applying ACI 349 and other
ACI codes are adopted as requested (see Section 3.2).
Section 4.2
Describe construction of the disposal facility, including construction methods of the
disposal units. [30 TAC ''336.707(5), 305.54(f)]
1. Comment: Answered in TNOD1 response.
2. Comment: The application has applied the word “may” to the following construction
technical specifications:
$      Appendix 4.2.2, Section 1.0-B (Cast-in-place Concrete Layer) states that “if the concrete
       cannot be protected during adverse weather, WCS may postpone placement operations.”
$      Appendix 4.2.3, Part 2.1-G (Reinforced Concrete) states that “cement may be sampled
       and tested for compliance at any time.”
$      Appendix 4.2.3, Part 2.7-A.2 (Reinforced Concrete) states that “fly ash may be sampled
       and tested for compliance at any time.
$      Appendix 4.2.3, Part 2.7-B.2 (Reinforced Concrete) states that “natural pozzolan may use
       [sic] instead of fly ash”



March 31, 2006                                 1                                 TNOD2
                                       Attachment 4
                            Second Technical Notice of Deficiency
                                     January 30, 2006

                                         Construction

$      Appendix 4.2.3, Part 3.3-B (Reinforced Concrete) states that “High Range Water
       Reducer may be added at the job site.”
Requested Action: Please fully specify all relevant procedures related in the production/creation
of reinforced concrete for use at the proposed facility, or alternatively, adopt ACI 349 as
requested in Section 4.1, Comment 1. The Applicant has clarified the context of the word “may”
in its response to TNOD1. However, the response does not specify what these optional activities
entail, under what circumstances these activities will be performed, how quality will be
maintained, or how changes will be reported.
Response: NUREG-1200 and NUREG/CR-5041 criteria for applying ACI 349 and other
ACI codes are adopted as requested (see Section 3.2 and Appendix 4.2.3).
3. Comment: Answered in TNOD1 response.
4. Comment: Appendix 4.2.3, Section 03 40 00 (Precast Concrete), Part 3.5 states that,
“canisters damaged in shipping may be repairs [sic] only when approved in advance by WCS.”
Requested Action: The information presented in the Applicant’s response to TNOD1 is not
sufficient to finalize a technical review and to determine compliance with agency rules. Please
list what defects would be allowed under WCS approval, what defects would be considered to be
repairable and what type of repair would be performed in such cases.
Response: The provision that allowed WCS to accept repaired concrete canisters has been
removed from the Technical Specifications, Appendix 4.2.3, Section 03 40 00, Precast
Concrete.
When the concrete canisters arrive at the WCS site, the applicant will inspect/evaluate the
condition of the canisters for damage. If the concrete canisters are damaged such the
integrity has been affected, then the canister(s) will be returned to the
manufacturer/supplier at their cost. Canisters will be accepted by the applicant in
accordance with Part 1.4, ‘Acceptance,’ of Section 03 40 00. The applicant will not make
repairs to the concrete canisters. The specification titled, Precast Concrete (Section 03 40
00, Appendix 4.2.3) has been revised; specially refer to Part 1.4 for ‘Acceptance,’ and Part
3.3 for ‘Damage.’
5. Comment: 30 TAC §336.716(f) states that “No waste shall be disposed of until the executive
director has inspected the land disposal facility and has found it to be in conformance with the
description, design, and construction described in the application for a license.” One way of
ensuring that the design and construction of the facility is in conformance with the design and
construction indicated in the application for a license is through the submission of as-built
drawings and construction certifications. However, no specific plan for submitting these
documents and drawings were found in the application.
Requested Action: The revised “Construction Quality Assurance and Quality Control Plan” has
been reviewed. However, the plan does not provide for TCEQ approval of the “red-lined” plans

March 31, 2006                                  2                                TNOD2
                                       Attachment 4
                            Second Technical Notice of Deficiency
                                     January 30, 2006

                                          Construction

to insure that the changes made in the field are in conformance with the design and construction
of the license application. Please provide a plan for submitting documentation or other method,
which will allow the TCEQ to verify that design and construction of the facility will conform to
the design and construction in the application. Also, this plan should address submittal of
documentation on how any deviations from approved methods in the construction phase,
otherwise meet the requirements of the specifications, standards, and design submitted to TCEQ.
Response: The WCS Construction Certification Report has been moved to Attachment D
and includes TCEQ in the final submittal process of “redline-plans” for TCEQ’s review
and approval. This report explains how the changes meet the approved specifications,
standards, and design will accompany the drawings submitted to TCEQ (see
Appendix 4.2.3, Attachment D, “Construction Certification Report”).
6. Comment: Answered in TNOD1 response.
7. Comment: Answered in TNOD1 response.
Section 4.4
Provide plans for the operation of a monitoring program during the land disposal facility
site construction. Measurements and observations shall be made and recorded to provide
data to evaluate the potential health and environmental impacts during the construction of
the facility and to enable the evaluation of long-term effects and the need for mitigative
measures. The monitoring system shall be capable of providing early warning of releases of
radionuclides and chemical constituents before they leave the disposal site boundary. [30
TAC '336.731(b)]
1. Comment: 30 TAC §336.730(b)(2) states that “Waste designated as containerized Class A,
Class B, Class C . . . shall be disposed of in the following manner: . . .in such a manner that the
waste can be monitored [emphasis added] and retrieved.” NUREG-1200 and NUREG/CR-5041
Vol.2, “Recommendations to the NRC for Review Criteria for Alternative Methods of Low-Level
Radioactive Waste Disposal” recommend monitoring such waste in terms of structural
performance of the structure holding the waste, which also assists in verifying design
assumptions and providing “reasonable assurance that there will not be a need for ongoing active
maintenance of the disposal site following closure” as specified in 30 TAC §336.709(4). To meet
these requirements, guidance documents recommend monitoring for the following structural
parameters within the disposal facility: settlement of the disposal foundation, strain on the
concrete structures, and movement of contraction joints in the concrete structures.
Settlement
NUREG/CR-5041 recommends a settlement monitoring system, which can measure and record
differential settlement of the disposal unit foundation during and after construction. This is
essential in that it helps evaluate stresses and strains in the subsurface, and when used in
conjunction with surface surveys, can determine whether the cover, waste matrix, and/or the


March 31, 2006                                  3                                  TNOD2
                                        Attachment 4
                             Second Technical Notice of Deficiency
                                      January 30, 2006

                                           Construction

disposal foundation is subsiding. The application provides information on “settlement monitors”,
which are described as benchmarks, and “walkover inspections”. While these tools are helpful in
describing and evaluating the surface, they do not provide any indication as to any structural
distress underground.
Strain
NUREG/CR-5041 recommends monitoring the strain on the concrete structures using strain
gauges. These devices can be used to measure internal stresses, which are essential in providing
assurance that the containment structures are performing as indicated in the application.
Furthermore, measuring strain will help assess the stresses on the concrete structure over time,
and could possibly detect the stability of the structures in the long-term. The application,
however, makes no apparent reference to monitoring the strain.
Movement of contraction joints
Measuring the movement of contraction joints in the concrete structures is recommended due to
the inherent nature of thermal expansion/contraction of all materials, including concrete. This
thermal energy may come from the radioactive or chemical properties of the waste. The joints
provide a release of the buildup of these thermal stresses, but as a result, provide a potential for
infiltration of liquid into the structure and/or escape of radioactive waste constituents from these
structures. The joints on the canisters may come from the lid/canister interface or other specified
locations. Again, the application makes no apparent reference to monitoring movements of
joints.
NUREG/CR-5041 also recommends the optional structural monitoring of measurements of
stresses, deflections, pore pressures, as well as internal concrete variables, such as shrinkage,
temperature, moisture, and corrosion.
Requested Action: Please provide plans for monitoring settlement, strain and joint movement in
proposed concrete structures. The construction of a structure according to a plan, even a plan that
contemplates the results of computer modeling, does not obviate the requirement for monitoring
during construction and post-construction periods.
Response: WCS agrees that the facility performance should be monitored. Given the
vulnerability of gauges, WCS proposes that a more accurate and reliable way to monitor
the facility performance would be through regular elevation measurements of the tops of
the canisters. Elevation measurements will provide a three-dimensional record of how the
facility and its individual components are performing. Elevation measurements will also
provide for accuracy, durability, and consistency in the long-term performance monitoring
of the facility.
Settlement and strain will be reflected in the top of the canister columns. Once a canister is
placed in the facility, a record will be made of its elevation and coordinates. As canisters
are added to the array, a three-dimensional set of coordinates of each canister in the entire


March 31, 2006                                    4                                  TNOD2
                                       Attachment 4
                            Second Technical Notice of Deficiency
                                     January 30, 2006

                                          Construction

array is built. Regularly scheduled elevation measurements will be made in a grid pattern
on the top tier of canisters. Any conditions that will cause concern regarding settlement or
strain will be reflected in the surface and recorded in these elevation measurements.
The concrete canisters do not have joints to monitor.
Elevation results will be checked against design standards for acceptable settlement. The
FLAC model provides anticipated settlements.
Strain will be reflected in individual column subsidence. Column elevations will be
compared to the design standards for the canisters. The SAP2000 model provides the
design analysis for making this comparison. More specific guidance for this process may be
found in the Structural Monitoring and Remediation Plan located in Section 4.
2. Comment: NUREG/CR-5041 recommends a remedial action plan corresponding to the
structural monitoring mentioned in the previous comment. This plan should indicate the
“limiting values or action levels” of the measurements and “the response to be taken if these
values are exceeded.” These responses should be justified and time allowed for these responses
should also be indicated.
Requested Action: No remedial action plan that responds to structural performance issues was
found in the appendix cited in the TNOD1 response provided by the Applicant. Please provide a
remedial action plan relating to the monitoring of the structural performance within the disposal
unit.
Response: A Structural Performance Monitoring and Remediation Plan has been inserted
into the Closure/Post Closure Plan in Section 6. A section regarding limiting values and
action levels related to the facility structure as outlined by NUREG/CR-5041, 2.6.2.8 is
included in this Structural Performance Monitoring and Remediation Plan.




March 31, 2006                                  5                                 TNOD2

				
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