PLANNED CHANGE NOTICE:
SALT DISPOSAL INVESTIGATIONS WITH A FIELD SCALE HEATER TEST
AT THE WASTE ISOLATION PILOT PLANT
Submitted to the U.S. Environmental Protection Agency (EPA)
Under the EPA's 40 CFR Part 194 Certification of the Waste Isolation Pilot Plant
August 5, 2011
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TABLE OF CONTENTS
Acronyms ii
Executive Summary iii
1.0 Description and Rationale for the Field Test at W1PP 1
1.1 Introduction 1
1.2 Description of the SD1 Facility 2
2.0 Impacts during Mining and Operation of SDI 4
2.1 Response at Station A 4
2.1.1 Mining Plan for SDI 4
2.1.2 Settling of Aerosol Particles during Mining 6
2.1.3 Temperature Change at Station A from SDI Heaters 8
2.2 Closure Phase 9
3.0 Impacts of SDI Testing on Long-Term Performance 10
3.1 Thermal Analysis 10
3.2 Mechanical Effects 11
3.3 Long-Term Performance Prediction 11
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Acronyms
CBFO
Carlsbad Field OtTice
CCDF
complementary cumulative distribution function
CFR
Code of Federal Regulations
CRA
Compliance Recertification Application
DOE
U.S. Department of Energy
DRZ
Disturbed Rock Zone
EPA
U.S. Environmental Protection Agency
NMED
New Mexico Environmental Department
PA
Performance Assessment
PABC-2009
Performance Assessment Baseline Calculation performed in 2009
PCN
Planned Change Notice
SDI
Salt Disposal Investigations
WIPP
Waste Isolation Pilot Plant
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Executive Summary
The U.S. Department of Energy (DOE) Carlsbad Field Office (CBFO) is notifying the U.S.
Environmental Protection Agency of its plan to perform a field scale heater test at the Waste
Isolation Pilot Plant (W1PP). This field test is part of a broader program of Salt Disposal
Investigations (SDI) that is described in A Management Proposal for Salt Disposal
Investigations with a Field Scale Heater Test at WIPP (DOE 2011). As demonstrated in this
planned change notice (PCN), there is no appreciable impact to either the operation of Station A
or to the long-term performance of the WIPP as a result of the proposed SDI activities. As a
result of the conservative assumptions used in the analyses and the lack of discernible impact, the
test parameters analyzed in this PCN could be expanded with minimal effect on repository
performance. The focus in this PCN is on the potential impacts from the in situ testing on the
operation and long-term performance of the WIPP; the plans for laboratory-based salt testing are
beyond the scope of this PCN because this type of testing does not directly affect the operation
and closure of the WIPP facility.
A primary goal of the SDI field test is to measure the properties and behavior of in situ salt in
response to temperature in excess of 160°C. The preliminary planning for the SDI test uses five
8.5 kilowatt (kW) heaters in mined alcoves of a central pillar. The preliminary design envisions
a two-year heating phase followed by an 18- to 24-month cool-down phase after the heaters are
turned off. After the cool-down phase, personnel will reenter the test alcoves to perform
additional testing on the halite adjacent to the heaters. This PCN uses a test with a two-year
heating/two-year cool-down phase as the base case and considers a test with a four-year
heating/two-year cool-down phase as a bounding case.
The operational impacts to WIPP resulting from the construction and operation of the SDI test
will be negligible because the SDI facility1 will be in a remote, newly mined area of the WIPP
repository that will be far from underground waste emplacement operations at WIPP. All mining
for the SDI test occurs in the northern section of the underground facility, historically termed the
"Experimental Area." The access drifts and alcoves for the SDI heaters will be approximately
700 meters from Panel 1, which is the waste panel closest to the test area. In addition, there are
no significant impacts from mining for SDI because there will be no mining of waste
emplacement panels while the SDI facility is being mined, with the exception of minor
maintenance activities in the main facility.
The potential impacts from the construction of the SDI facility on the density of salt aerosol and
on the return air at the shrouded probes at Station A have been evaluated. Based on the
estimated travel times in the SDI airways and the dilution of salt aerosol from SDI mining with
the return air from the main facility, the mining of the SDI facility will not impose a significantly
greater aerosol loading on the return air at Station A than current mining operations at WIPP.
The maximum temperature change at Station A is predicted to be very small, less than 0.3°C,
because the heat from the SDI test would be diluted in the total return air flow. It follows that
the operation of the SDI test will not have significant impacts on the shrouded probes at Station
1 As used in this PCN, the term "SDI facility" refers to the total underground excavations for this field test,
including the entries that provide access to and ventilation air for the test area. The term "SDI test area" refers to the
test alcoves and test access mains directly surrounding the test pillar, as shown in Figure 2.
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A. This impact assessment does not change the existing procedures to inspect the shrouded
probes on a periodic basis to ensure that salt buildup does not impact the ability of these probes
to take a representative sample of particulates in the ventilation air stream.
Long-term impacts to the WIPP facility resulting from the construction and operation of the SDT
test will be negligible because the SDI test area will be in a remote, newly mined area that is at
least 700 meters away from the waste emplacement areas in the WIPP repository. The following
long-term impacts have been considered:
¦ The SDI test will generate a thermal pulse that moves outward from the test area into the
surrounding halite. The magnitude of this thermal pulse at Panel 1, the repository panel
that is closest to the SDI test area, is less than 0.1°C and therefore small enough to be
screened out of performance assessment (PA) calculations on the basis of low
consequence.
¦ The SDI heaters may induce peak salt temperatures well above 160°C near the back of
the alcoves, and higher temperature results in a significant increase in the creep rate of
intact salt. Deformation of the host rock surrounding the alcoves will redistribute
mechanical stresses as the alcoves close. I lowcver, this stress redistribution near the
alcoves is primarily a local effect because salt creeps most rapidly in high temperature
regions with the greatest deviatoric stresses, and will not have a significant impact on the
waste emplacement panels, which are at least 700 meters away.
¦ Mining of the SDI facility does not result in a significant increase in subsidence relative
to the subsidence from the WIPP waste emplacement areas because the extraction ratio2
for the SDI facility is on the order ofG.15. In addition, there are no significant impacts
from mining for SDI because there will be no mining of waste emplacement panels while
the SDI facility is being mined, with the exception of minor maintenance activities in the
main facility.
¦ The impact of the SDI facility on long-term performance has been evaluated in the SDI
PA (Camphouse et al. 2011). The mean total normalized releases for the SDI PA are
essentially identical to the mean total normalized releases for the Performance
Assessment Baseline Calculation performed in 2009 (PABC-2009), which is the current
PA baseline. There is therefore no impact on long-term performance of the disposal
system as a result of the construction and operation of the SDI field test and the disposal
system remains in compliance with the containment requirements of 40 Code of Federal
Regulations (CFR) Part 191 (EPA 1993), as implemented by the criteria in 40 CFR Part
194 (EPA 1996).
2 The volumetric extraction ratio is the ratio of the volume of mined salt to the total volume of the facility, which
includes the volume of the pillars). For a room and pillar mine like the WIPP, the volumetric extraction ratio and the
areal extraction ratio (i.e., the ratio of the excavated area to the total footprint of the facility, including pillars) are
equal and referred to as the extraction ratio.
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1.0 Description and Rationale for the Field Test at WIPP
1.1 Introduction
The Waste Isolation Pilot Plant (WIPP) is the first underground repository for disposal of
transuranic waste generated by defense-related activities. This dry and geologically inactive site
is situated 42 km (26 miles) east of Carlsbad, New Mexico, at a depth of 655 meters (2,150 feet)
below land surface. The WPP facility is situated on a 42 km2 (16 square mile) tract that is
permanently withdrawn from operation and occupancy under federal land laws and administered
by the U.S. Department of Energy (DOE). The underground facility is comprised of a series of
panels and entry drifts mined in the halite of the Salado Formation, and accessed through lour
shafts. The repository received its first waste shipment on March 26, 1999 and has received
9,598 waste shipments as of May 25, 2011.
The Secretary of Energy has made areas of the mine available for scientific research, beginning
with the OMNISita and Majorana projects in April and December of 2001, respectively. Since
2001, other experiments have been installed in the north section of the underground facility,
provided the experiments could be performed without compromising the WIPP's primary
mission of waste disposal. Figure 1 illustrates the locations of the current underground
experiments.
AM 0
Figure 1. Locations of Current Underground Experiments at the WIPP Facility
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The proposed facility for Salt Disposal Investigations (SDI) will be located in a remote, newly
mined area of the existing experimental region of the WIPP repository and therefore separate
from the operational/waste emplacement side of the WIPP repository. The SDI field test will be
conducted by multiple participants; however, the procedures of the WIPP facility operating
contractor with respect to health, safety, and all underground operations will control operational
aspects of the SDI test.
1.2
Description of the SDI Facility
The preliminary design of the SDI field test is described in A Management Proposal for Salt
Disposal Investigations with a Field Scale Heater Test at WIPP (DOE 2011). A primary goal of
the SDI field test is to measure the properties and behavior of in situ salt in response to
temperature in excess of 160°C. The preliminary planning for the SDI test uses five 8.5 kW
heaters in mined alcoves of a central pillar that is surrounded by two test access drifts (see Figure
2)-
¦Huu'Ofl Ainovn (S)
n
ObMMviillori/
Inslrtircofitnliwi
AtniiuH i'J)
Test Mana Drtrt i
-Date Collection Cul-Out
and Core Sloraij* Area
(-1Z * 30']
1) All dlmarolcn* an ki feat.
2) Access drtlts an typically IT Huh
3) T»*t«i™™ m typkally 1 ff high
4) All dtmonstaiiB ore approximate and dapandant upon
operational and ctxwtnrctbn eonstdaraflons
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Figure 2. Plan View of the SDI Test Area
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The preliminary design for the SDI test envisions a two-year heating phase followed by an 18 to
24 month cool-down phase after the heaters are turned off (DOE 2011, Section 3.5.2). After the
cool-down phase, personnel will reenter the test access drifts and test alcoves to perform
additional testing on the halite adjacent to the heaters.
SDl-related activities include extensive laboratory studies and thermo-mechanical analyses that
will assist in defining the final configuration and duration of the field scale test. This planned
change notice (PCX) uses a test with a two-year heating/two-year cool-down phase as the base
case, and considers a test with a four-year heating/two-year cool-down phase as an alternative,
bounding case.
Page 3 of 14
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2.0 Impacts during Mining and Operation of SD1
The operational impacts to the W1PP facility resulting from the construction and operation of the
SDI facility are expected to be minimal because the SDI facility will be in a remote, newly
mined area of the existing experimental region of the WIPP repository and therefore far from
underground waste emplacement operations. In addition, there will be no mining of waste
emplacement panels during the mining for the SDI facility.
Figure 3 is a plan, view of the overall mining plan for the SDI facility. All mining for the SDI test
occurs in the northern section of the underground facility. The test access drifts and alcoves for
the SDI heaters, shown in detail in Figure 2, are located in the northeast quadrant of the WIPP
repository. In particular, the test alcoves and test pillar are located outside the shaft pillar area,
which is shown by the red curves in Figure 3. This is important because it minimizes the
potential impacts from mining and from the test heaters on the host rock surrounding the shafts,
ensuring that the shafts remain in a stable gcomechanical environment.
This section considers the potential impacts on Station A, at the top of the Exhaust Shaft, from
mining the SDI facility and from the heating phase of the SDI test. This section considers the
potential impacts on the conduct of underground operations at WIPP from mining and operation
of the SDI facility. The potential impacts on long-term performance are discussed in Section 3,
2.1 Response at Station A
2.1.1 Mining Plan for SDI
The total mined tonnage for the SDI entries is approximately 150,000 tons (see Figure 3), which
corresponds to a mined volume of 61,200 m3 (2,160,000 ft3) (personal communication from Ty
Zimmerly), The SDI entries will typically be 3,96 m (13 ft) high and 4.88 m 06 ft) wide.
Representative dimensions for the test alcoves are shown in Figure 2. The planned sequence of
mining for the SDI facility will be as follows:
¦ Mine two north-south drifts, denoted as E-500 and E-650 in Figure 3, to provide a
connection for ventilation air to flow directly from the SDI facility to the exhaust shaft.
The new mining extends east from E-140 at the N-780 cross-drift and at N-940, then
turns south and runs to the extension of the S-400 cross-dri ft at the exhaust shaft. Until E-
500 and E-650 connect to the exhaust shaft, the return air from mining will be routed to
flow in the E-140 drift from N-780 to S-90, cross over into the E-300 drift, mix with
exhaust air from the maintenance shop, and flow down E-300 to S-400 and the exhaust
shaft. After E-500 and E-650 connect to the exhaust shaft, the return air from the SDI
flows directly to the exhaust shaft, separately from the return air from other parts of the
WIPP underground facility. The pathway for the return air is an important consideration
in evaluating the settling of salt aerosol particles out of the return air.
¦ Mine four east-west drifts, with two to the south and two to the north of the SD I test area.
The return air from this mining will go directly to the exhaust shaft through the newly
mined E-500 and E-650 drifts, as noted above.
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Figure 3. Mining Plan for the SDI Test Area to the Northeast of the Existing Repository
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Mining will be performed in two stages: an initial cut that is typically 4.27 m (14 ft) wide by
3.05 m (10 ft) high and the final cut to trim the ribs then the floor to 4.88 m (16 ft) wide by 3.96
in (13 ft) high. The sequencing of initial and final cuts will be different for the major drifts:
¦ E-500 and E-650 will be mined to the initial cut just short of connecting to S-400. Then a
small portion of drift just north of S-400 will be cut to final so that ventilation controls
can be installed. Then E-500 and E-650 will be connected to S-400 and these drifts will
be completed to the final cut, with the return ventilation air flowing directly to S-400.
¦ When mining of the four east-west access drifts to the SDI test area begins, the north-
south drifts to S-400 will be at their final dimension and the return ventilation air will
flow directly through these north-south drifts to S-400. The final cut for the east-west
access drifts will directly follow the initial cut.
The ventilation air flow during mining will be about 26.0 m /s (55,000 cubic feet per minute
(cfm)) through the SDI facility. Before E-500 and E650 connect to the exhaust shaft, the air
velocity3 in the E-14G drift will be about 0.65 m/s (127 ft/min) north of N-250 (where E-140 is
about 7.32 m (24 ft) wide and 5.49 m (18 ft) high) and about 0.83 m/s (164 ft/min) south of N-
250 (where E-140 is about 7.32 m (24 ft) wide and 4.27 in (14 ft) high). All drift dimensions are
nominal. After connecting to the exhaust shaft, the air velocity will be about 2.0 m/s (394 ft/min)
in the initial cut drift and about 1.3 m/s (256 ft/min) in the final cut drift, assuming that all the
return air flow goes through a single drift (i.e., E-500 or E-650).
2.1.2 Settling of Aerosol Particles during Mining
DOE will continue to monitor and inspect the shrouded probes at Stat ion A, at the lop of the
exhaust shaft, on a periodic basis to ensure that salt buildup from mining activities does not
impact the ability of these probes to take a representative sample. The analysis in this section
evaluates the likely size distribution of suspended aerosol particles at the base of the exhaust
shaft from mining the SDI facility, but does not imply that DOE expects there will be a need to
make changes to the procedure for monitoring and inspecting the shrouded probes at Station A.
Mining the SDI facility will produce nuisance dust, halite particles, and soot particulates (from
the operation of machinery) with a wide range of particle sizes. Mining of the SDI facility will
use the same equipment and methods as those that arc used in mining the waste panels, so the
aerosol produced by mining will generally be the same in terms of composition and size
distribution as those from waste panel mining. However, the size distribution of the aerosol at
the base of the exhaust shaft may be different because of different travel times for the return air.
The impact of travel times through SDI entries on the size distribution of aerosol particles is
analyzed here.
Smaller aerosol particles will remain suspended in the ventilation air, while larger aerosol
particles will settle out while the ventilation air passes through the return airways of the SDI
facility. This settling process is important for the shielded probes at Station A, at the top of the
exhaust shaft. Operational experience shows that a high density of salt aerosol particles in the
3 Air velocity is calculated as the volumetric flow rate divided by the cross-sectional area of the opening, For
example, velocity in the £-140 drift is (26.0 m3/$)/(7.32 m * 5.49 m) = 0,65 m/s
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ventilation return air enhances salt buildup on the shrouded probes, which could affect the
representativeness of sampling bv the probes.
Until E-500 and E-650 connect to S-400, the return air from mining will be routed through the E-
140 drift from N-780 to S-90, cross over into the E-300 drift, mix with the exhaust air from the
maintenance shop, flow down E-300 to S-400, and then flow to the base of the exhaust shaft.
The travel time in E-140 is approximately (530 ft)/(127 ft/min) + (340 ft)/(164 ft/min) = 6.2
minutes or 370 s. This calculation incorporates the different flow velocities between N-780 and
N-250 and between N-250 and S-90, as calculated at the end of Section 2.1.1. This is a minimum
travel time because additional time will be required for flow down E-300.
Once the final cut on the north-south drifts is completed, the two sets of east-west drifts, one on
each side of the SD1 test area, will be mined. The minimum flow distance in E-500 or E-650 is
slightly greater than 900 ft (see Figure 2), allowing a minimum settling time of (900 ft)/(264
ft/min) = 3.4 minutes or 200 s. This flow velocity is based on the final cut drift, as defined at the
end of Section 2.1.1. This is also a minimal travel time because mining may occur far from the
entry to the E-500 or E-650 drifts.
Terminal settling velocities for a wide range of particle sizes have been tabulated (Avallone et
al., 2007, Figure 18.1.1). For example, a 20 (.im diameter aerosol particle has a terminal settling
velocity of about 2.5 em's. At this terminal velocity, a 20 urn diameter aerosol particle will fall
from the top to the bottom of a 3.96 m (13-ft) high drift in (396 em)/(2.5 cm/'s) = 158 s, or less
than 3 minutes. It follows that most 20 jim diameter aerosol particles from mining of the SDI
facility will settle out before they reach the exhaust shaft, based on the minimum travel times of
3.4 minutes or 6.2 minutes calculated above. On the other hand, a 10 pm diameter aerosol
particle has a terminal settling velocity of about 0,5 cm/s (Avallone et al., 2007, Figure 18.1.1)
and a settling time in a 3.96 m high drift of about 800 s or 13 minutes. So the settling of 10 pin
diameter aerosol particles is expected to be minimal before the return air reaches the exhaust
shaft. This behavior is similar to the salt aerosol generated by mining the waste emplacement
panels, wherein the maximum particle size is estimated to be on the order of 10 to 15 p,m in
diameter.
An additional consideration is that the flow in the SDI facility during mining is a small fraction
of the total flow up the exhaust shaft. During normal operation of the WIPP facility, one or two
main fans (called "700" fans), draw air through the facility and up the exhaust shaft. In the
normal ventilation mode, with two main fans running, the nominal flow rate in the exhaust shaft
is 201 (standard) m3/s (426,000 standard cfm). In the alternate ventilation mode, with one main
fan running, the nominal flow rate is 123 standard m3/s (260,000 standard cfm). The planned
flow through the SDI section during mining is 26.0 m3/s (55,000 cfm), or 13% and 21% of the
total flow in normal and alternate ventilation modes, respectively. The salt aerosol from SDI
mining will therefore be significantly diluted with the relatively clean ventilation air from the
main facility. The return air from the main facility will be relatively clean because there will be
no mining (except for occasional maintenance activities) in the main facility when mining for
SDI occurs, and hence little salt aerosol in the return air from the main facility.
Based on the estimated travel times in the SDI facility and the dilution of salt aerosol from SDI
mining with the return air from the main facility, the mining of the SDI facility should not
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impose a significantly greater aerosol loading on the return air at Station A than current mining
operations at WIPP. The shrouded probes will continue to be inspected on a periodic basis, as
noted at the beginning of this section, to ensure that salt buildup does not impact the ability of
these probes to take a representative sample.
2.1.3 Temperature Change at Station A from SDl Heaters
During the heating phase of SDI, current plans call for 8.5 kW heaters in each of five test alcoves
(DOE 2011, Section 3.5.2 and Figure 3-11). These heaters have a maximum total power of 42.5
kW. If ventilation air is flowing through the test access drifts and heater alcoves, heat transfer
from the hot host rock will increase the temperature of the return air stream from the SDI facility.
The following analysis demonstrates that the temperature increase at Station A, at the top of the
exhaust shaft, is minor because the return air from the SDI facility mixes with the return air from
the main facility.
The temperature change at Station A can be estimated from the total heat released by the five
SDI heaters, assuming that all of their thermal energy is transferred directly to the ventilation air
flow. This is an extremely conservative, "worst case" calculation because most of the energy
released by the heaters goes into the surrounding salt, rather than being immediately released
into the ventilation air. For example, there may be very limited or no ventilation air flowing
through the SDI test area during the heating phase, and hence no thermal energy is transferred to
the ventilation air during the heating phase. During the cool-down phase, the heat emitted from
the rock to the ventilation air is generally smaller than the total capacity of the SDI heaters
because the energy from the SDI heaters is stored in the surrounding body of rock and is not
immediately released into the ventilation air stream.
This calculation does not consider the cooling that occurs as the return air ascends in the upcast
exhaust shaft. The cooling in a vertical, upcast shaft occurs for all ventilation Hows and can be
analyzed in detail (McPherson 1993, Section 8). However, the focus of the present analysis is on
the heat energy from the SDI test providing an additional change in the temperature of the total
return air at Station A, excluding the cooling associated with an upcast shaft.
A simple energy balance for a constant pressure process estimates the maximum temperature
change from the SDI heaters on the total air flow in the exhaust shaft:
Q-h\„rCP.mAT, (l)
or AT = -r—^, (2)
VP**,*
where Q is the total power generation of the heaters [kW = kJ/s], V is the total volumetric flow
1 * * » » 4 3 I
rate through the exhaust shaft [m /s], paif is the density of the ventilation air [kg/m ], cp ajr is the
specific heat capacity of air [kJ/kg/°C], and Aris the change in temperature of the ventilation air
[°C] . The values of these parameters are as follows:
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V ~ 201 m3/s (standard) in normal ventilation mode, with two 700 fans running;
pmr = 1.2 kg/ m3 (for dry air at atmospheric pressure and 25 °C); and
cp air = 1.021 kJ/kg/°C ((Avallone et al., 2007, Table 4.2.22 at 300K).
Then the maximum temperature change in the normal ventilation mode with five heaters running
is calculated as:
ATnorm = (42.5 kW)/(201 m3/s)/(1.2 kg/m3)/(1.021 kJ/kg/°C),
= 0.17°C,
and the maximum temperature change in the alternate ventilation mode, with a flow rate of 123
standard m3/scc, is calculated as:
ATalt = (42.5 kW)/(123 m3/s)/(1.2 kg/m3)/(1.021 kJ/kg/°C),
= 0.28°C,
Even if all the heat from the SDI heaters is transferred directly to the ventilation air flow, the
maximum temperature change at Station A is very small, less than 0.3DC, because the heat from
the SDI test is being diluted in the total return air flow. The thermal energy from the SDI tests
will therefore not adversely affect the samples taken at Station A. This conclusion is
independent of the duration of the heating phase or of the split of ventilation air flow within the
SDI facility because the calculation is a simple, bounding energy balance that is independent of
these considerations.
2.2 Closure Phase
After completion of the SDI testing, the experimental facilities will be closed according to a
predetermined protocol. This will include:
¦ Removal of equipment from the underground, including the equipment for thermal and
mechanical measurements of high temperature salt and any supporting equipment and
materials.
¦ Closure of the experimental cavities when no further use is planned. Closure be in
accordance with standard mining practice.
During permanent closure of the repository, the total facility will be closed according to an
approved closure plan. This closure plan will determine the appropriate closure requirements for
the underground experimental areas.
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3.0 Impacts of SDI Testing on Long-Term Performance
Long-term impacts to the WIPP facility resulting from the construction and operation of the SDJ
field experiment are expected to be minimal because the SDI test area will be in a remote, newly
mined area of the existing experimental region of the WIPP, separated from the WIPP
emplacement areas by at least 700 meters of intact halite with minimal excavation. This section
considers the potential impacts on long-term performance from the presence of the heaters for
the SDI test, from the potential for test alcoves to partially or completely close during the heating
phase, and from the additional excavated volume required to construct the SDI experimental
area.
3,1 Thermal Analysis
The SDI test will generate a thermal pulse that moves outward from the test area into the
surrounding halite. The magnitude of this thermal pulse at Panel 1, the repository panel that is
closest to the SDI test area, has been analyzed using a model for heat conduction that represents
the SDI test as two line sources in a cylindrical disk that is bounded on bottom by Marker Bed
139 and on top by Marker Bed 138. These Marker Beds are assumed to be adiabatic boundaries,
with no heat flow upward or downward through the Marker Beds. This is an extremely
conservative assumption for temperature rise because the adiabatic boundaries confine the
thermal pulse to the disk between the Marker Beds,
Kuhlman (2011) provides the analytic methodology for the solution of this thermal conduction
problem in cylindrical symmetry and the numerical results for the temperature rise at 40 m, 100
m, 200 m, 400 m, and 700 m as a function of time (Kuhlman 2011, Figure 1). The peak
temperature rise at Panel 1 is calculated to be less than 0.02°C at about 1,500 years (Kuhlman
2011, Figure 1). These calculations are for the base case with a two-year heating phase.
Calculations were not performed for the bounding case, but the peak temperature rise is
estimated to be less than 0.04°C because the bounding case has twice as much energy input to the
halite as the base case.
The conclusion from this model is that the long-term temperature rise from the SDI test will be
significantly less than 0.1 °C in Panel 1 and in the rest of the repository. This temperature rise is
much less than the temperature increases of 2°C to 3°C that have been screened out of
performance assessment (PA) calculations for Feature, Event, and Process (FEP) W13, Heat
from Radioactive Decay:
"/« summary, previous analyses have shown that the average temperature increase in
the WIPP repository caused by radioactive decay of the emplaced CH- and RH-TRU
waste will he less than 2 °C (3.6 °F). Temperature increases of about 3 °C (5.4 °F) may-
occur in the vicinity of RH-TRU containers with the highest allowable thermal load of
about 60 W (based on the maximum allowable surface dose equivalent for RH-TRU
containers). Potential heat generation from nuclear criticality is discussed in Section
SCR-6.2.1.4 and exothermic reactions and the effects of repository temperature changes
on mechanics are discussed in the set of FEPs grouped as W29, W30, W31, W72, and
W73 (Section SCR-6.3.4.1). These FEPs have been eliminated from PA calculations on
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the basis of low consequence to the performance of the disposal system." (DOE 2009,
Appendix SCR-2009, Section SCR-6.2.1.2).
The long-term temperature rise from the SDI test, less than 0.1°C at the repository, is therefore
small enough to be screened out of PA calculations on the basis of low consequence, and will not
have a significant impact on any temperature-dependent processes in the repository.
3.2 Mechanical Effects
The SDI heaters may induce peak salt temperatures well above 160°C (DOE 2011, Figure 3-2).
Salt deformation is dominated by viscoelastic creep (plastic behavior) at elevated temperatures,
and higher temperature results in a significant increase in the creep rate of intact salt (DOE 2011,
Figure 3-1). Given the sensitivity of creep rate to temperature, it is possible that the alcoves with
heaters may partly or completely close during the heating phase of the SDI test. Deformation of
the host rock surrounding the alcoves will redistribute mechanical stresses as the alcoves close.
This deformation continues until the salt creep reduces the magnitude of the deviatoric stress
components to zero and a lithostatic state of stress is reestablished in the host rock.
Stress redistribution near the alcoves is primarily a local effect because salt creeps most rapidly
in high temperature regions with the greatest deviatoric stress. High temperature and high
deviatoric stress occur in the host rock near the alcoves, enhancing the local deformation of the
rock salt. Far from the alcoves, the enhanced deviatoric stresses and elevated temperature effects
in the alcoves are greatly reduced or eliminated. In this context, "far" is often interpreted as
outside the "zone of influence" of an excavation (Brady and Brown 2006, Section 7.2). For
example, stresses tend to asymptote by 2 to 3 times the radius of a circular opening in rock
(Jaeger, Cook and Zimmerman 2007, Figures 8.1, 9.2(b), and 9.3(a)) or by 5 times the radius of a
circular opening in an elastic/fractured rock mass (Brady and Brown 2006, Figure 7.20). Since
the alcoves are 3.4 m (11 ft) wide and 3.0 m (10 ft) high (DOE 2011, Figure 3-12), partial or
complete closure of the alcoves for the SDI test will have no impact on the mechanical response
of the repository panels, which arc at least 700 m (2300 feet) away from the SDI test. A similar
argument also indicates that closure of the entry mains leading from the repository to the SDI test
area will also have negligible impact on the mechanical response of the repository panels
because these entries will be in a remote, newly mined area of the existing experimental region
of the WIPP and separated from the waste emplacement panels by hundreds of meters.
Mining of the SDI facility will not result in a significant increase in surface subsidence relative
to the surface subsidence from the WIPP waste emplacement areas. The extraction ratio for the
SDI facility is quite low, on the order of 0.15, in order to ensure that the integrity of the shaft
pillar is not compromised by the SDI-related mining activities. This approach also ensures that
the mining of the SDI facility will not result in a significant increase in surface subsidence
relative to the subsidence from the panels, rooms, and access mains for the underground waste
emplacement areas.
3.3 Long-Term Performance Prediction
SDI testing will require new mining in the northeastern quadrant of the existing repository (see
Figure 3). The mined volume for the SDI facility is about 62,000 m3 (2,200,000 ft3). By way of
11 of 14
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comparison, the volumes of the Operations Area and Experimental Area in the BRAGFLO grid
for the Performance Assessment Baseline CaIculation-2009 (PABC-2009) (Clayton el al, 2010)
are 37,300 m3 and 87,700 mJ, respectively. The mined volume for the SDI facility therefore
increases the volume of the combined Experimental and Operations Areas by almost 50%.
In general terms, increasing the volume of these areas reduces the pressure within the waste
emplacement panels because the larger volume of these areas provides a low pressure reservoir
for any gas generated in the waste emplacement areas. Reduced pressure in the repository will
tend to increase brine inflows from the disturbed rock zone (DRZ) and from the anhydrite
marker beds into the repository. The presence of the lower pressure reservoir in the Experimental
and Operations Areas will also increase brine flows from the waste emplacement panels to the
Operations and Experimental Areas because gas generation in the waste emplacement panels
maintains these areas at higher pressure than the Operations and Experimental Areas. Assessing
the impacts of the competing effects of reduced repository pressure and increased brine flows on
long-term performance requires a performance assessment.
The impact of the SDI facility on long-term performance has therefore been evaluated in the SDI
PA (Camphouse et al. 2011). The SDI PA is based on the PABC-2009, which is the current PA
baseline. The volume of the Experimental Area has been increased to represent the presence of
the SDI test facility in the northeast quadrant of the repository. The SDI PA uses the Option D
panel closures, which are included in the PABC-2009.
Figure 4 demonstrates that the presence of the SDI facility results in mean total normalized
releases that are essentially the same as the mean total normalized releases for the PABC-2009 at
all probability levels. The numerical values in Table 1 (Camphouse et al. 2011, Table 6) also
demonstrate that the statistics for the distribution of complementary cumulative distribution
functions (CCDFs) for total normalized release about the mean are similar for the SDI PA and
for the PABC-2009, Any differences in Table 1 are primarily caused by lower releases from
spallings due to reduced gas pressure in the waste emplacement areas. A more complete
discussion of the inputs to and results from the SDI PA can be found in Camphouse et al. (2011).
Table 1. SDI PA and PABC-2009 Statistics on the Overall Mean for Total Normalized Releases
in EPA Units at Probabilities of 0.1 and 0.001
Mean Total
90m
Lower
Upper
Release
Probability
Analysis
Release
Percentile
95% CL
95% CL
Limit
0.1
SDI PA
0.093
0.15
0.090
0.095
1
PABC-2009
0.094
0.16
0.091
0.096
1
0.001
SDI PA
1.1
1.0
0.38
1.8
10
PABC-2009
1.1
1,0
0.37
1.8
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1
SDI Overall Mean
PABC-2009 Overall Mean
— — — Release Limits
~i—i—i i i i in 1—i i i 11 mi 1—i—i i i 11ii 1—i—i i 11 111 1 ¦ i i i 11 ii i 1—i—i- i t i n
0.0001
0,001
0.01
0.1
10
100
R = Total Release {EPA Units)
f igure 4. Overall Mean CCDFs for Total Normalized Releases from SDI PA and PABC-2009
13 of 14
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4.0 References
Aval lone, Eugene A., Theodore Baumeister III, and Ali M, Sadegh, Editors, 2007, Marks'
Standard Handbook for Mechanical Engineers, Eleventh Edition, McGraw-Hill, New York,
New York.
Brady, B.H.G. and E.T. Brown, 2006. Rock Mechanics for underground mining. Third Edition.
Springer, Dordrecht, The Netherlands.
Clayton, D.J., R.C. Camphouse, J.W. Garner, A.E. Ismail, T.B. Kirchner, K.L. Kuhlman, and
M.B. Nemer, 2010. Summary Report of the CRA-2009 Performance Assessment Baseline
Calculation. Sandia National Laboratories, Carlsbad, New Mexico. KRMS 553039.
Camphouse, R. Chris, Dwayne C. Kicker, Thomas B. Kirchner, Jennifer J. Long,, and James J.
Pasch, 2011. Impact Assessment of SDJ Excavation on Long-Term W1PP Performance. Revision
0. Sandia National Laboratories, Carlsbad, New Mexico. ERMS 555824.
Jaeger, J.C., N.G.W. Cook, and R.W. Zimmerman, 2007. Fundamentals of Rock Mechanics,
Fourth Edition. Black well Publishing, Maiden, Massachusetts and Oxford, United Kingdom.
Kuhlman. Kris, 2011. SDI Heater Testing Long-Term Thermal Effects Calculation. Sandia
National Laboratories, Carlsbad, New Mexico.
McPherson, Malcolm J., 1993. Subsurface Ventilation and Environmental Engineering.
Chapman & Hall, London, United Kingdom.
New Mexico Environment Department, 2010, Waste Isolation Pilot Plant Hazardous Waste
Permit. Santa Fe, New Mexico. November 30, 2010.
U.S. Department of Energy (DOE) 2009. Title 40 CFR 191 Parts B and C Compliance
Recertification Application. DOE/WIPP-09-3424. Carlsbad Field Office, Carlsbad, New Mexico.
U.S. Department of Energy (DOE), 201 LA Management Proposal for Salt Disposal
Investigations with a Field Scale Heater Test at WIPP. DOE/CBFO-11-3470, Revision 0. U.S.
Department of Energy, Carlsbad Field Office, Carlsbad, New Mexico. June 2011.
U.S. Environmental Protection Agency (EPA), 1993. 40 CFR 191: Environmental Radiation
Protection Standards for the Management and Disposal of Spent Nuclear Fuel, lligh-Level and
Transuranic Radioactive Wastes; Final Rule. Federal Register, Vol, 58, 66398-66416.
U.S. Environmental Protection Agency (EPA), 1996. 40 CFR 194: Criteria for the Certification
and Recertification of the Waste Isolation Pilot Plant's Compliance with the 40 CFR Part 191
Disposal Regulations; Final Rule. Federal Register, Vol. 61, 5223-5245.
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Enclosure 2
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U.S. DEPARTMENT OF ENERGY
CARLSBAD FIELD OFFICE
A MANAGEMENT PROPOSAL FOR
SALT DISPOSAL INVESTIGATIONS
WITH A FIELD SCALE HEATER TEST AT WIPP
Foundation of
Supporting
Knowledge
WIPP
BASIS
June 2011
DOE/CBFO-11-3470
REVISION 0
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INTENTIONALLY LEFT BLANK
Salt Disposal Investigations
June 2011
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EXECUTIVE SUMMARY
SALT DISPOSAL INVESTIGATIONS
PROJECT INTRODUCTION
This management proposal provides a science-based scope of work (with time and cost
estimates) for a defined scope of research (laboratory work and modeling efforts) intended to
establish the foundation for a proof-of-principle field test for disposal of heat-generating nuclear
waste. This management proposal is considered a preliminary and internal scoping proposal
meant to reach a decision-in-principle within the United States Department of Energy (DOE)
headquarters. Test-specific requirements such as parameter identification, data quality
objectives, instrumentation, calibration requirements, precise borehole and gauge placement,
sample control, test procedures, data collection processes, and other test or modeling specific
information will be provided in an ensuing field test plan to be developed in fiscal year 2012.
Detailed cost estimates and schedules will be developed as a function of DOE fiscal year
planning. The figure below provides a general overview of how this management proposal fits
in relationship to other Salt Disposal Investigations (SDI) documents and records planned as a
result of this project.
Relationship of the Management Proposal to Other SDI Documents and Records
Salt Disposal Investigations iii
June 2011
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Disposal of nuclear waste in salt remains a viable, yet underutilized concept in the United
States. The well-recognized success of the WIPP mission for the disposal and isolation of
defense transuranic (TRU) waste provides strong positive testimony in support of salt disposal
for a variety of nuclear wastes. Bedded salt formations in the United States hold great promise
toward solving major disposal issues for thermally and radioactively hot waste currently
managed by the United States DOE Office of Environmental Management (DOE-EM).
Previous salt repository studies and operations have been adequate to demonstrate safe
disposal of TRU waste in salt. However, for thermally hot waste, there are gaps in the
experimental data that are addressed in this management proposal. The developmental history
of the current management proposal began in 2008 when DOE assessed the need for a second
repository to augment the proposed Yucca Mountain Project. As a part of that process, the
DOE Office of Nuclear Energy (DOE-NE) funded a scoping study for the feasibility and efficacy
of a comprehensive repository in salt, with the DOE-EM Carlsbad Field Office (CBFO) and its
science and operations contracting organizations providing support.
The final report of the scoping study (Carter et al. 2011) provided a proof-of-principle layout and
operational strategy for a repository that would meet the combined disposal needs for
reprocessed high-level waste, low-level waste, and greater-than-Class-C wastes for the next
one hundred years. The report pointed toward a near-term science-based program to gain
public confidence and provide a regulatory compliance framework that would close gaps in our
current knowledge for salt repositories. To strengthen the SDI proposal, DOE-EM requested a
formal and comprehensive compilation of all previous work in salt, current status, and additional
science necessary to fill gaps and extend our current understanding, most specifically for heat-
generating waste disposal. The resulting report (Hansen and Leigh 2011), coupled with the
referenced scoping study, provides the primary basis for work proposed in this SDI proposal.
Directed laboratory and field research can help reduce uncertainties regarding thermally driven
processes involved with decay storage and disposal in salt and increase technical
understanding for those potential missions. The research program proposed would directly test
a disposal arrangement that balances heat loading with waste and repository temperature limits.
It would fill information gaps in current knowledge of the thermomechanical, hydrological, and
chemical behavior of salt and wastes disposed in salt and form the technical foundation for
design, operation, coupled process modeling, and performance assessment of future salt
repositories for heat-generating nuclear waste.
This management proposal, originally developed in February 2010, was revised in March 2011
at the request of DOE Headquarters to reflect efficiencies and cost savings realized if the test
program was conducted in the area of the WIPP and not in an existing salt or potash mine. The
WIPP is an operational disposal facility permitted by the New Mexico Environment Department
for disposal of hazardous (mixed) waste and certified by U.S. Environmental Protection Agency
for radioactive waste disposal. As such, proposed activities in this proposal will be performed in
accordance with applicable regulatory requirements (Section 2.3). This will ensure that all
proposed activities will not impact disposal operations or long-term repository performance. The
use of the WIPP underground for the field test portion of SDI realizes significant cost savings by
avoiding the development and installation of mining infrastructure at some other existing salt or
potash mine of similar depth. Of course, there remain substantial costs associated with
performance of SDI, as delineated in this management proposal to perform the tests in WIPP.
The area to the north of the access shafts (far north of waste disposal operations) is already
configured with electrical power and fiber optic cable to service basic science experiments.
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Additionally, an existing trained workforce, mining infrastructure, nuclear safety bases, and a
quality assurance program will make the field test component of the SDI at WIPP cost
appreciably less while supporting a more defensible experiment compared to bringing these
essential elements of a field test to another commercial mine.
In June 2011, the CBFO developed a QAPD specific to these SDI activities (DOE. 2011). The
SDI QAPD was modeled after the highly effective and time-proven CBFO QAPD and describes
an NQA-1-2008 compliant Quality Assurance Program for the science-based studies
concentrating on high thermal loading effects in bedded salt. Existing WIPP procedures are
adapted as appropriate to accommodate the SDI program, thereby taking advantage of the
existing mature and audit-tested programmatic and technical processes established for a
successful repository program.
Pursuant to the completion of the SDI QAPD, this current version of the management proposal
(June, 2011) was revised to addresses technical and programmatic comments received from a
review commissioned by the DOE-NE Fuel Cycle Technologies Program's Used Fuel
Disposition Campaign. This process was controlled through the CBFO procedure for document
review, Management Procedure CBFO-MP-4.2. Additionally, this version of the proposal
reflects a funding strategy of a two million dollar annual budget for the next two consecutive
fiscal years from DOE-EM, with DOE-NE contributing to the laboratory and modeling efforts
(see reference 22), followed by increased budgets in subsequent fiscal years to start the heating
phase in fiscal year 2015. The overall life cycle of the salt disposal investigations has
consequently been extended to ten years as a result of the restrained start to the field proof-of-
principle test,
PROJECT MANAGEMENT, QUALITY ASSURANCE, AND SAFETY
The overall management of the work proposed within this SDI project will be through CBFO.
The CBFO defines quality requirements through a Quality Assurance Program Document
(QAPD), similar to that used for the WIPP program. The SDI QAPD describes an American
Society of Mechanical Engineers Nuclear Quality Assurance 2008 Edition (NQA-1) compliant
QA program for the science-based studies concentrating on high thermal loading effects in
bedded salt. Those portions of the SDI investigations funded by Used Fuel Disposition
Campaign (UFDC) of the DOE-NE will be managed according to the judgment of the UFDC
management team.
The Los Alamos National Laboratory's Carlsbad Operations (LANL-CO) office will function as
the project management organization, responsible for day-to-day test management and
coordination, similar to a successful model used at the Nevada Test Site and the Yucca
Mountain Project, ensuring that all test-related information and data activities are consistent and
focused. In its management capacity, LANL-CO will report to the CBFO Project Manager.
Sandia National Laboratories (SNL), LANL, and other potential scientific entities, will provide
Principal Investigators to inform and advise test management to ensure the test is as
productive, integrated, and efficient as can be achieved.
Washington TRU Solutions (WTS), the WIPP Management and Operating Contractor, will
provide engineering, construction, and test support personnel to provide for the test bed (e.g.,
drift mining, borehole coring, electrical, ventilation) and aid in test installation.
The primary collaborators on this management proposal, predominantly from LANL and SNL,
have direct salt repository experience and have conducted decades of salt research and
Salt Disposal Investigations
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thermal testing, both in the laboratory and the field. Experience directly relative to the types of
field and laboratory activities described in this management proposal include field work at the
Nevada Test Site, large in situ thermal tests at Yucca Mountain, and experimentation at WIPP.
The authors have vast experience in broader repository science efforts in the areas of process
and performance assessment modeling, and licensing. Appendix C provides a list of key
contributors to this proposal and a summary of related experience.
Each proposal participant has extensive experience and an exemplary record of safety related
to field and laboratory work activities, including a culture and value structure that promotes
safety in the workplace. Each participant will conduct work safely and responsibly; ensure a
safe and healthful working environment for workers, contractors, visitors, and other on-site
personnel; protecting the health, safety, and welfare of the general public. This is done through
an institutional framework which embodies processes that align with the principles and functions
of Integrated Safety Management.
PROPOSED RESEARCH PROGRAM
The proposed research program would substantially enhance our knowledge of the behavior of
thermally and radioactively hot nuclear waste in salt and will provide fundamental data for the
model validation and evaluation of concepts for disposal in salt. The program has been divided
into six elements:
1. Functional and Operating Requirements and Test Planning
The project benefits greatly from the fact that it can utilize existing infrastructure at WIPP
and will be situated in well characterized rock salt. The test itself will require a description of
functional and operational requirements (F&OR) for a field test. The work to develop the
F&OR document has been funded in FY11. Detailed test plans will then be developed,
reviewed, and delivered in FY12.
2. Laboratory Thermal and Mechanical Studies to Support the Field Test
Elevated salt temperatures will cause accelerated salt-creep deformation, which leads to a
more rapid encapsulation of the waste. Laboratory studies on the salt from the field-test site
are designed to examine intact and crushed salt at the high temperatures expected for
alcove disposal.
3. Laboratory Chemical, Hydrologic, and Material Studies
Laboratory studies will establish the key factors that control brine migration, radionuclide
solubility, and mobility at elevated temperatures. In addition, material interaction data will be
obtained that can be used to evaluate waste forms.
4. Coupled Process Modeling
Prediction of the behavior of the field test will initially be made using the best-available
models of thermomechanical behavior, including creep, damage, healing, reconsolidation,
and coupled processes. Improvements have been identified for certain elevated
temperature constitutive models and brine availability including vapor phase transport.
Some of the thermomechanical information will be gleaned from laboratory studies and
validated as the field test progresses. The models will be updated using data collected in
this study to continuously improve and validate predictive capability. Thus, a rigorously
developed modeling capability will be available for use in future design and performance
assessment activities for disposal in salt.
Salt Disposal Investigations
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5. Field Test Installation and Operation
The conceptual field test provides full-scale, real-world data for the models used to predict
behavior of salt and brine at elevated temperatures, The proposed test is designed to push
the limits of salt heat loading and waste temperature. One important field test design
criterion is high thermal loading. If the test proceeds at a design thermal load of 40 watts per
square meter (W/m2), the test bed will experience temperatures in excess of 160°C in the
salt mass (see section 3.4.1), above where most data have been acquired to date. Steady
state creep rate of WIPP horizon salt accelerates one order of magnitude for each increase
of approximately 12 degrees Centigrade (°C), The affected salt near the heater is expected
to flow rapidly and perhaps decrepitate (i.e., burst owing to the pressure of fluid inclusions).
Upon review of this very aggressive temperature limit, a decision to modify the test
temperature in the formal review of the test configuration will be made. However these
considerations will be informed early by the laboratory testing. Experimentation in the
laboratory will also present significant technical challenges in terms of instrumentation
survival and data acquisition. As the laboratory thermomechanical testing proceeds in
advance of the field test, laboratory experience will greatly inform the field-test team. In
addition, the field test will produce data directly applicable to a potential repository by testing
a disposal arrangement.
6. International Collaboration
Collaboration with the European Union countries (particularly Germany) will avail technical
staff of the latest international developments in salt repository sciences.
GOALS FOR CONDUCTING THIS PROPOSED WORK
The primary reasons to conduct the work described in this proposal are: 1) demonstrate a
proof-of-principle concept for disposal in salt, 2) bound salt thermomechanical response, 3)
investigate thermal effects on intact salt in situ, 4) apply laboratory research to intact and
crushed salt, 5) develop full-scale response for dry, crushed salt, 6) observe and document
fracture healing in situ, 7) characterize and understand brine liberation and migration, 8) track
moisture movement and vapor phase transport in situ, 9) measure the thermodynamic
properties of brines and minerals at elevated temperatures, 10) study repository interactions
with waste container and constituent materials, 11) measure the effect of temperature on
radionuclide solubility in brine, and 12) develop a validated coupled process model for disposal
in salt for high heat-load wastes.
Information derived from the proposed field test, laboratory tests, and modeling activities will be
transferable to other potential salt repositories. Transferability of experimental and analogue
information forms a fundamental scientific tenet, and has been recognized in repository
programs, including salt, for decades.
COST AND SCHEDULE
The total project cost is approximately $43M over 10 years. Mining and engineering labor are
included as existing WIPP resources and infrastructure; therefore, those total costs are shown,
but not included in the SDI specific budget necessary to complete the work. Consumables and
equipment, however, are included as direct costs. Costs (in thousands of dollars) by element
and year are shown below:
Salt Disposal Investigations
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vii
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Element
FY11
FY12
FY13
FY14-20
Totals
2.0 Management, QA, and Safety
$250
$1,000
$900
$4,600
$6,750
2.4 International Collaboration
$0
$200
$200
$1,550
$1,950
3.1 Operating Rqmts. and Test Planning
$200
$0
$0
$0
$200
3.2 Laboratory Thermal and Mech. Studies
$250
$400
$600
$2,200
$3,460
3.3 Laboratory Hydrologic, Chemical, and
Material Studies
$0
$210
$700
$2,600
$3,510
3.4 Coupled Process Modeling
$0
$300
$700
$1,900
$2,900
3.5. Field Test Installation and Operations
$0
$800
$900
$22,400
$24,100
** Existing WIPP Mining Resources and
Infrastructure
($1,500)
($1,500)
($1,500)
($4,500)
Total SDI Budget (new) per year
$700
$2,910
$4,000
$35,250
$42,860
Total Cost (incl. existing resources)
$700
$4,410
$5,500
$36,750
$47,360
Primary actions and test planning (FY 11):
• Complete the SDI Management Proposal
• Complete a Test Plan for laboratory testing for crushed salt in the laboratory to measure
thermomechanical behavior across a variety of temperature, stress, and porosities
• Initiate laboratory tests on crushed salt
• Develop an NQA-1-compliant Quality Assurance Program Document and associated
procedures
• Complete the F&OR document for the field test
Test planning, initial mining and laboratory studies (FY12):
• Begin elevated temperature tests on intact salt in the laboratory to measure
thermomechanical behavior across a variety of temperatures and stresses
• Continue the laboratory tests on crushed salt
• Develop and review the detailed field test plan with equipment lists, instrumentation and
borehole layouts, data quality objectives, etc.
• Comprehensively evaluate existing and available information from past thermal
experiments
• Develop the criteria for the underground test design and layout
• Begin mining the underground access drifts to the test bed location
• Begin installing ventilation control and power distribution
• Write a test plan for laboratory studies of water liberation and brine migration in salt
• Begin measuring the thermodynamic properties of brines and minerals at elevated
temperatures in the laboratory
• Develop a test plan and begin measuring the effect of temperature on radionuclide
solubility in the laboratory
• Develop a test plan and begin studying repository interactions with waste container and
constituent materials in the laboratory
• Evaluate and use coupled multiphysics modeling capability for field test configuration
and analysis
Salt Disposal Investigations
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Initial studies (FY13):
• Continue development of fully coupled TM(H) code and model for field test analysis.
• Continue laboratory thermomechanical testing and chemistry experiments
• Conduct laboratory studies of water liberation and brine migration
• Develop test plan for intact core testing in the laboratory
• Procure test equipment and instrumentation for the field test
• Develop work control and safety basis for the field test
• Complete mining of the underground access drifts
• Develop the documented safety analysis for the field test
• Mine the field test bed
Field test implementation (FY14):
• Core instrumentation boreholes
• Implement the field test equipment, including data collection equipment and fiber optic
communication equipment
• Investigate salt properties of test bed location
• Preparedness assessment for field test start and baseline measurements
• Continue laboratory thermomechanical testing and chemistry experiments
• Conduct laboratory studies of water liberation and brine migration
• Continued development of fully coupled THMC code and model for field test analysis
Conduct the proof-of-principle field test (FY15 - 20)
• Heating start on field test - FY 15
• Investigate thermal effects on intact salt in situ
• Develop a full-scale response for dry crushed salt
• Observe and document fracture healing in situ
• Track moisture movement and vapor phase transport in situ
• Complete laboratory thermomechanical testing and chemistry experiments
• Complete laboratory studies of water liberation and brine migration
• Cool-down of field test by FY 19
• Post-test forensics, mine-back and post-test coring in FY 19 and FY 20
• Complete the final test and data reports
• Develop calibrated, coupled TM(H) model
Salt Disposal Investigations
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TABLE OF CONTENTS
EXECUTIVE SUMMARY iii
1 PROJECT INTRODUCTION 1
2 PROJECT MANAGEMENT, QUALITY ASSURANCE, AND SAFETY 17
2.1 TEST MANAGEMENT STRUCTURE 17
2.2 QUALITY ASSURANCE AND SAFETY 18
2.3 WIRP REGULATORY COMPLIANCE CONSIDERATIONS 19
2.4 INTERNATIONAL COLLABORATION 20
3 PROPOSED RESEARCH PROGRAM 22
3.1 FUNCTIONAL AND OPERATIONAL REQUIREMENTS AND TEST PLANNING 22
3.2 LABORATORY THERMAL AND MECHANICAL STUDIES 23
3.2.1. Intact Salt Studies 24
3.2.2. Crushed Salt Studies 25
3.3 LABORATORY HYDROLOGIC, CHEMICAL, AND MATERIAL STUDIES 27
3.3.1. Hydrologic Studies 28
3.3.2. Chemical and Material Studies 31
3.3.3. Measure the Thermodynamic Properties of the Brines and Minerals at Elevated Temperatures... 31
3.3.4. Study Interactions with Waste Container and Constituent Materials at Elevated Temperatures.... 32
3.3.5. Measure the Effect of Elevated Temperature and Ionizing Radiation on Brine Chemistry 34
3.3.6. Measure the Effect of Temperature on Radionuclide Solubility 35
3.3.7. Measure Radionuclide Oxidation Distribution and Redox Control at Elevated Temperatures 35
3.4 COUPLED PROCESS MODELING 36
3.4.1. Thermomechanical Benchmark Modeling 37
3.4.2. Hydrologic and Chemical Benchmark Modeling 39
3.5 FIELD TEST PROOF OF PRINCIPLE 40
3.5 1. Preliminary Work: Conceptual Disposal Concepts 41
3.5.2. Conceptual Field Test Design 45
3.5.3. Mining and Construction Support 53
3.5.4. Geophysical Assessment and Monitoring of the Field Test 55
3.5.5. Feasibility of Reentry into the North WIPP Experimental Area 57
4 COST AND SCHEDULE 59
4.1 COST AND SCHEDULE 59
4.2 MAJOR ACTIVITIES AND ACTIONS 64
5 REFERENCES 66
APPENDIX A: PROPOSED AREA WITHIN WIPP FOR THE SDI HEATER TEST A-1
APPENDIX B: THE NEED FOR SALT INVESTIGATIONS AND FIELD TESTS B-1
APPENDIX C: KEY CONTRIBUTORS TO THE SDI PROPOSAL C-1
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LIST OF TABLES AND FIGURES
LIST OF TABLES
TABLE 1-1 Summary of In situ Salt Thermal Tests 11
TABLE 3-1 Uniaxial Compression Test Matrix 25
TABLE 3-2 Oedometer Consolidation Test Matrix 26
TABLE 3-3 Thermal Conductivity Test Matrix 27
TABLE 3-4 Test Matrix for Alcove-Specific and Bounding Material Interaction Tests 33
TABLE 3-5 Test Matrix for the Effects of Temperature and Radiation on Brine Chemistry 34
TABLE 3-6 Test Matrix for the Effect of Temperature on Radionuclide Solubility in Brine 35
TABLE 3-7 Test Matrix to Establish the Key Factors that Control Radionuclide Oxidation
State 36
TABLE 3-8 Instrument Costs per Alcove for the In Situ Thermal Test 52
TABLE 3-9 Equipment Costs for the In Situ Thermal Test 52
TABLE 3-10 Partitioning of Responsibilities - Construction & Ops Support and Testing 53
TABLE 3-11 Mining and Infrastructure Costs (in thousands of dollars) 54
TABLE 4-1 Cost by Element - Budget Constraint on the First Two Fiscal Years 60
TABLE 4-2 Cost by DOE Organization in FY12/FY13 61
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LIST OF FIGURES
FIGURE 1-1 Science Based Foundation for TRU and HLW Disposal in Salt 2
FIGURE 1 -2 Comparison of Surface Exposure for RH TRU Waste (Being Disposed at Waste
Isolation Pilot Plant) and Defense HLW 4
FIGURE 1-3 Stable Geologic Salt Formations within the 48 Contiguous States 6
FIGURE 1-4 Mohr's Circles of Stresses at Failure for Ten Rock Salts at Room Temperature 7
FIGURE 1-5 Conceptual Schematic of Model-Driven Process for Repository Investigations 14
FIGURE 2-1 SDI Organizational Structure with Funding Partnerships 18
FIGURE 3-1 Strong Influence of Temperature on Creep of Natural Rock Salt 24
FIGURE 3-2 Preliminary Temperature Distribution for the Proof-of-Principle In Situ Field Test 38
FIGURE 3-3 Preliminary Reconsolidation Calcs for the Proof-of-Principle In Situ Field Test 39
FIGURE 3-4 Disposal Concept Used as the Basis of the Proposed Field Testing Program 42
FIGURE 3-5 Alcove-Scale Thermal Simulation: 100°F Isotherm as a Function of Time 43
FIGURE 3-6 Repository-Scale Thermal Simulation 43
FIGURE 3-7 Average Waste Temperatures Verses Time for Different Assumed Behaviors 44
FIGURE 3-8 Perspecitve View of the Mining Layout for the SDI In Situ Thermal Test 46
FIGURE 3-9 Area I View of a Typical SDI Alcove 46
FIGURE 3-10 Proposed Area within WIPP for the SDI In Situ Test 48
FIGURE 3-11 Plan View of the Mining Layout for the SDI In Situ Test 49
FIGURE 3-12 Plan and Profile View of a Typical Alcove 50
FIGURE 3-13 Location of Past Field Tests Located Within WIPP 58
FIGURE 4-1 Estimated Schedule for Test Program Duration (Constrained FY12/FY13) 62
FIGURE 4-2 Estimated Schedule for Test Program Duration (Accelerated Scenario) 63
June 2011
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1. PROJECT INTRODUCTION
Long-term decay storage and permanent deep geologic disposal of heat-generating nuclear
waste (such as high-level waste [HLW]) in salt lie at the intersection of research on repository
performance, waste form behavior in different geologic formations, and public acceptance of the
U.S. Department of Energy (DOE) Office of Environmental Management - Office of Nuclear
Energy (EM-NE) Initiative for Waste Disposal Research. Public understanding and confidence
in decayed storage or permanent isolation of radioactive waste in salt have improved as a result
of more than a decade of successful disposal operations at the Waste Isolation Pilot Plant
(WIPP). EM-NE-directed research can leverage this positive experience by reducing
uncertainties regarding thermally driven processes involved with decay storage and disposal in
salt, and therefore further increasing technical understanding for those potential missions. This
point is explicitly included in the Memorandum of Understanding between the two offices on the
topics of Used Nuclear Fuel and Radioactive Waste Management and Processing Research
and Development (DOE, 2011). In collaboration with international salt repository programs,
laboratory experiments, and simulated heat-generating waste/salt interaction tests, the next few
years will answer remaining questions and more fully inform future repository programs. The
proposed work will build upon a foundation of excellence in salt repository applications that
began almost 50 years ago.
Bedded salt formations in the United States hold great promise for solving major disposal issues
for thermally and radioactively hot waste currently managed by DOE EM. This management
proposal involves non-mission-specrfic testing to evaluate the efficacy of bedded salt for
thermally hot nuclear waste. The research, development, and demonstration contained in this
proposal will advance the technical baseline for disposal in salt and could significantly inform
future nuclear waste repository decisions.
Figure 1-1 illustrates how this management proposal builds upon an enormous base of
knowledge from early test programs, many of those at WIPP (e.g., see Table 1-1, historic listing
in Appendix B, and Hansen and Leigh. 2011), and that, with a relatively small and achievable
incremental amount of modeling, laboratory testing, and field demonstration testing, new paths
toward waste disposal designs and a future repository in salt can be realized. Information
derived from the proposed field test, laboratory tests, and modeling activities will be transferable
to other salt sites. Transferability of experimental and analogue information forms a fundamental
scientific tenet, and has been recognized in repository programs, including salt, for decades.
Salt Disposal Investigations
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Figure 1-1: Science Based Foundation for TRU and HLW Disposal in Salt
Foundation of
Supporting
Knowledge
W1PP
BASIS
The Challenging Waste Issue
DOE-EM currently manages the defense HLW from reprocessing over 160,000 tons of used
nuclear fuel (UNF) in the states of Washington, Idaho, and South Carolina. Figure 1-2
compares the surface exposure rate of defense remote-handled transuranic (TRU) waste
(currently being disposed of at the WIPP) and defense HLW. The defense HLW processing
system in place today reflects a set of baseline technologies that, among other things,
presupposed the co-disposal of DHLW (as borosilicate glass waste forms) and UNF at Yucca
Mountain. A recent NAS study on waste form technology options (NAS, 2011) concluded that
there is still time to improve upon the current path forward by incorporating scientific advances
into the defense cleanup program to maximize efficiencies. The study highlighted the potential
opportunities of developing more efficient waste form production methods, and stressed the
need to match a waste form and accompanying engineered barriers to the disposal
environment. The issues driving the development of waste forms have traditionally included
waste loading, radiation tolerance, and long-term durability in an environment in which contact
with water leads to radionuclide mobilization and transport through the natural environment. Salt
is unique as a disposal medium in that, for an appropriately selected site, the amount of water
contacting the waste under undisturbed conditions is expected to be minimal. This feature could
be exploited by adopting more efficient, safe, and cost-effective processes upstream of HLW
emplacement in the repository by relaxing the requirement that the waste form be exceptionally
durable in the presence of water. Thus, research to confirm or disprove critical hypotheses on
the efficacy of salt as a disposal medium for thermally hot waste is a logical next step that could
lead to a viable disposal concept and to more efficient upstream options for defense waste
streams.
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The Nuclear Waste Policy Act and its amendments legislate that HLW eventually be emplaced
in a national waste repository. However, the national repository is also intended to be a
retrievable storage site during the operational phase and possible disposal site for UNF from the
commercial nuclear power industry, now representing about 60,000 metric tons (MT). These
two waste forms (defense HLW and commercial HLW) are radically different in radioactivity,
future value, and many other attributes. Additionally, if UNF is reprocessed in the future, it is
potentially limiting to connect UNF storage with either decayed storage or the deep geologic
permanent disposal of HLW fractions from recycling. With the new administration's intent to
rethink the issue of long-lived radioactive waste disposal in America, it is prudent that DOE
research other possible geologic disposal solutions that do not directly link UNF retrievable
storage with defense HLW disposal. If retrieval is less important, permanent isolation in salt
potentially emerges as a robust geologic solution.
Note that retrievability to maintain ready access to a potentially valuable material is a different
concept than maintaining the ability to reverse a decision to bury waste because of a flaw
discovered in the safety case after disposal operations have begun. An NAS study on "adaptive
staging" of repository programs (NAS, 2003) advocated retrievability from the standpoint of
ensuring that decisions can be reversed, even to the extent of being able to remove wastes
placed in the repository until permanent closure of the facility. In this context, retrieval of waste
from a salt repository is technologically feasible, if necessary due to safety considerations, by a
process of locating the waste package and re-mining to recover it. Thus, recovery of waste to
reverse a decision due to safety concerns would be achievable, whereas retrieval for the
purpose of recovering a valuable resource should not be considered as a viable option for salt.
Therefore, the issue of retrievability should not be viewed as an impediment to proceeding with
a research program for HLW disposal in salt.
The preliminary views from the subcommittees of the Blue Ribbon Commission (June 2011)
noted that regardless of the future nuclear fuel cycle chosen, a geologic repository will be
needed. At this point in time it is not possible to categorically state that such a future repository
will be loaded with only HLW or only UNF, and it is quite likely that both waste types will be
disposed of even if reprocessing is used to intercept new UNF at some future time. It is also
premature to categorically state whether or not defense/government/commercial wastes will be
segregated for disposal or will be disposed of together. This makes it prudent to study the
disposal of disparate waste type characteristics for the higher volume wastes that may be
expected. Therefore, for this proposal, the range in higher volume waste characteristics will be
bounded by current descriptions of high-burnup UNF and HLW currently being produced
(SRNL) and slated to be produced (Hanford) in the near term.
With respect to civilian nuclear waste, there is no technical issue related to safety or adverse
environmental impact that creates an urgent need to identify a permanent disposal option.
Storage in spent fuel pools and in dry casks is deemed to be an appropriate technological
solution for at least 60 years beyond the licensed life of operation (U.S. NRC, 2010), and
applied R&D could be conducted to enhance the technical basis for even longer storage
periods. Long-term storage, with UNF stored either at reactor sites, or as recommended in a
recent MIT study {MIT, 2011), in a centralized storage facility, would provide the time needed
(several decades by most estimates) to assess various fuel cycle technology options before
choosing the most appropriate, sustainable fuel cycle for the future. If during that period, it is
determined that reprocessing would be desirable, the country would be faced with the need to
dispose of a variety of waste streams, including HLW. To prepare this HLW for disposal, many
of the unit operations and waste forms generated in a civilian UNF reprocessing future would be
similar to those already being executed to handle DHLW. This process knowledge would be put
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to use should the nation decide that reprocessing of civilian UNF is desirable. Extending that
concept to repositories, the proposed studies would have direct relevance to future disposal of
HLW from reprocessed UNF, potentially by identifying a viable, highly cost effective disposal
system. Even if it is ultimately decided that civilian UNF should be disposed of in an open fuel
cycle without reprocessing, the proposed studies would provide important information on the
behavior of salt under thermal loads that would be relevant to the assessment of salt as a
disposal medium for UNF.
This management proposal drives directly to key technical issues common to EM-NE initiatives
in waste disposal research. The program described here will vastly improve disposal options,
assess waste form performance in salt, and promote public confidence — all key building blocks
of the EM-NE initiative. Salt Disposal Investigations (SDI) will move forward with a science-
based research program on multiple fronts, laboratory research in hydrology, chemical, and
material studies, laboratory thermomechanical salt behavior, directed field testing of simulated
waste/salt interaction, and full integration and collaboration with similarly motivated research
centers in Europe. Deliberations on the future of nuclear energy directed toward decayed
storage and disposal of commercial HLW fractions from recycling wiil also benefit from research
proposed to resolve the key questions about thermal salt storage. This work leverages off
earlier work and the substantial knowledge base concerning HLW storage and disposal in salt.
Figure 1-2: Comparison of Surface Exposure for RH TRU Waste (Being Disposed at Waste
Isolation Pilot Plant) and Defense HLW
RANGE FOR REM0TE-HANDLED TRU WASTE TYPICAL HIGH LEVEL WASTE FORMS
r A—7 s~j—A i—^
Hanford RH TRU Waste SI reams
*
Hanford Acidic Wasle
Vessel 7€ R/hr
Hanford Fully
Contaminated
Filler SOO r/ii
HEPA
irtlL RH TRU Wadle Streams
« AMI. Ffffl RH IBU t
.RAPI R A TRU
. INL SI earn Re formed Solids
LAIML RH Tf IU Waste SI re at
ORNL RH T 1U Wasle Sires
LMi
frAPL.
OEVNC,
SRS DWPF
WJLERH
TRy
HcW canisters
lanford Vitr ified HLW Canister @ 30
qui <580 R.'hr 10 4.100 Whr)
Average Canister 3240 R/hr
O* Hanford Concentrated
Receipt Vessel 129Q R/tir
Used hluctear Fuel 1-year After
Removal from Reactor 10,000 R'hr >
0+ .Design basis PWR package for
Yucca Mountain 1,130 R/hr
^ O* SRS Design Basis
Limit 6000 R/tir
West Valley Canisters
Average Garisler 32-10 R/hr
I
I
10 100 1,000 10,000
SURFACE DOSE RATE ROENTGEN/HOUR
0.1 1.0
Overlapping Range of HLW (including UNF) and RH TRU Waste Doss Rates
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Why Bedded Salt?
Ten years of successful operation of the WIPP have demonstrated the fiscal, operational, and
compliance efficiency of salt mining and defense TRU waste disposal. Salt investigations in the
United States and Germany support the concept of salt disposal for heat-generating waste as
well; however, there are some gaps in our knowledge base for the mechanical behavior of salt
and the hydrologic and chemical behavior of brine at higher temperatures, as well as how salt
interacts with waste constituents at higher temperatures. Heat management is an overriding
consideration in repository layout, and the very act of balancing the heat load underground
creates ample volume for disposal of non-heat generating wastes such as greater than class C
and low-level radioactive waste. Furthermore, depending on the results of this testing program
and accompanying performance assessment analyses, direct disposal of calcined or other
mineralized forms of waste, or other cost-effective changes to upstream processing, might be
found acceptable.
The positive attributes of salt that make it an effective medium for disposal and isolation of
hazardous, toxic, and radioactive materials have been recognized for over 50 years (NAS.
1957). As briefly discussed below, the attributes of salt are collectively important to its isolation
capability and provide the safety basis for isolation of embedded materials.
1) Salt can be mined easily. Salt has been mined for millennia. A wealth of underground
experience, including TRU waste disposal operations at WIPP, ensures that large-scale,
safe mining can be conducted in salt.
2) Salt flows around buried material and encapsulates it. Salt will slowly deform to
surround other materials, thus forming a geologic barrier that isolates waste from the
environment. Creep or viscoplastic flow of salt has been well characterized for many
applications. Research in the United States, coupled with international collaborations, has
played a significant role in development of this technical understanding.
3) Salt is essentially impermeable. The very existence of a salt formation millions of years
after deposition is proof that water has not flowed through the formation. The established
values for permeability of intact salt come from many industry applications, such as the
large-scale storage of hydrocarbon product in solution salt caverns. The undisturbed
formation permeability of salt is essentially too low to measure using traditional hydrologic
and reservoir engineering methods. In undisturbed and healed salt, brine water is not able
to flow to waste at rates that would lead to significant radionuclide mobilization and
transport.
4) Fractures in salt are self-healing. In terms of disposal, one of the most important
attributes of salt as an isolation medium is its ability to heal damaged areas. Damage
recovery is often referred to as "healing" of fractures. The healing mechanisms include
microfracture closure and bonding of fracture surfaces. Evidence for healing of fractures in
salt has been obtained in laboratory experiments and through observations of natural
analogs. Fracture healing can readily restore salt to a low permeability, as noted above.
5) Salt has a relatively high thermal conductivity. Thermal conductivity of natural rock salt
under ambient conditions is approximately 2 to 3 times higher than granite or tuff. A
relatively high thermal conductivity is a positive attribute in a salt repository for nuclear waste
because the heat is rapidly dissipated into the surrounding formation.
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6) Suitable salt formations exist in wide geographic distributions. There are multiple
locations with stable geologic salt formations within the 48 contiguous states (see Figure 1-
3) that could host a repository. Bedded salt is preferred over domed salt due to the
inherently larger areas contained in the bedded geologic salt formations, which leads to
flexibility in accommodating potentially long periods of repository operations. In addition,
salt formations have existed for millions of years in non-seismically active areas.
Figure 1-3: Stable Geologic Salt Formations within the 48 Contiguous States
Salt formations were actively studied for repository applications from the late 60's until the
NWPA amendment removed the bedded salt site in the panhandle of Texas from consideration
as the civilian repository for spent nuclear fuel and high level waste. In a global sense salt
mechanical, thermal, and hydrological properties are fundamentally similar. In the early years of
site investigations, basic properties of many salts were measured. For example, in Figure 1-4,
the failure envelopes for ten natural salts including both bedded and domal formations with a
variety of impurities show the similarity of strength and pressure sensitivity (Hansen et al.,
1980). Some of the other basic phenomena, such as dilatant response and plastic deformation
mechanisms, have commonality across a wide range of natural salt. These points are made to
emphasize that the fundamental studies encompassed in the SDI will be applicable to all salt
repository studies.
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Figure 1 -4: Mohr's Circles of Stresses at Failure for Ten Rock Salts at Room Temperature
RSI UWG 001-81-532
•o I? PCX) *
•10 0 fen «6 iO «0 'CO
f o 0 m *p to IC 50
*t**9
ifl O in 4* • » -on
•:#x
ie a it: *a t« io -va
««r jf FrtMO*
lu a ic ii *4 la
w •#*
•Of WCCK'l >SLiHNC
ccn Kino*
t* o ii it 10 •»
Why Study Bedded Salt at Higher Temperatures?
Laboratory and field studies of intact salt and crushed salt and the chemical interactions of salt
with waste packaging, waste forms, and waste constituents received a considerable amount of
attention in the 1980s. However, the upper temperature limit for the thermomechanical intact
salt tests has been about 200°C, and crushed salt and chemical interaction tests have been
conducted predominantly at room temperature. These past studies have been more than
adequate to demonstrate that disposal of TRU waste in salt is safe and efficient. However, for
thermally hot waste there are gaps in the experimental data that are addressed in this
management proposal. The proposed research, development, and demonstration of salt
efficacy for the safe and efficient disposal of thermally hot waste proposed here will provide the
basis for a single repository that can readily isolate large quantities of nuclear waste material, a
key component of a safe and secure nuclear future for the nation.
Salt Disposal Investigations
June 2011
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The main goals for conducting this work are:
• Demonstrate a proof-of-principle concept for disposal in salt WIPP experience has
demonstrated that placing waste in a pre-drilled borehole is cumbersome and difficult. This
disposal concept — proposed as a result of previous DOE-funded work (Carter et al. 2011 -
see section 3.5.1) — obviates the need for pre-drilled holes, as well as the difficult phase of
waste alignment and insertion into the pre-drilled hole. The proposed disposal concept is
simple, safe, and expedient. The outcome of this proposed testing, in concert with the
WIPP and analogue repository experience, will allow a more objective evaluation and
optimization of proposed future repository designs.
• Bound the salt thermomechanical response. This test will push the envelope in terms of
individual canister heat load and the average bulk salt temperature, thus ensuring that the
thermomechanical phenomena experienced in the test for disposal in salt encompasses all
likely thermal loads associated with future disposal.
• Apply laboratory research to intact and crushed salt. The fundamentals of high-
temperature intact salt response and hot, dry reconsolidation will be studied in the
laboratory. Information derived will inform field test planning and underpin the coupled
process models of the large-scale response.
• Investigate thermal effects on intact salt in situ. Elevated temperature in the near-field
environment will give rise to salt decrepitation (bursting caused by expansion of trapped
brine) in addition to stress-induced fracture. Note that these phenomena may be negative
or positive in terms of long-term performance, depending on the fate of liberated water and
the ability of fractures in salt to heal. High temperatures, fracture states, and brine liberation
drive important performance phenomena that will be investigated at repository scales in the
field test.
• Develop full-scale response for dry, crushed salt. Whereas the reconsolidation
processes of ambient crushed salt with a small amount of moisture are well understood
mechanistically (e.g. Brodsky et al. 1996), the large-scale reconsolidation of hot and dry salt
is less well documented. Understanding crushed salt reconsolidation in this setting is
essential to establish room closure response, thermal conductivity, and near-field
temperatures.
• Observe and document fracture healing in situ. Fracture healing is an important attribute
for disposal in salt. This experiment will allow evaluation of creation and healing of a
disturbed rock zone.
• Characterize and understand brine liberation and migration. Small amounts of brine
exist in natural bedded salt, trapped there since its ancient deposition, millions of years ago.
The brine exists in three forms: fluid inclusions, grain boundary brine, and hydrous
minerals. Laboratory experiments will be conducted to quantify brine migration and
characterize mineral reactions relevant to the water budget.
• Track moisture movement and vapor phase transport in situ. Because brine is
considered a key to the evolution of the disposal setting, its movement in this testing milieu
will be documented. Liberated brine will derive from the disturbed rock zone as enhanced
by the thermal pulse. Samples of various materials associated with the full-scale test will
Salt Disposal Investigations
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allow determination of what chemical reactions and transport might take place with the brine
movement.
• Measure the thermodynamic properties of brines and minerals at elevated
temperatures. Precise measurements of the pressure, volume, and temperature (PVT)
properties of brines are required for coupled process and performance assessment models.
• Study repository interactions with waste container and constituent materials.
Evaluation of the chemical interactions of a broad range of materials (see Table 3-4) and
waste forms in the laboratory will provide a scientific basis to evaluate waste form strategies
and engineer waste forms and packages to limit or preclude the migration of radionuclide
species in a salt based repository.
¦ Measure the effect of temperature on radionuclide solubility in brine. Radionuclide
solubility will control the source term of any thermally hot waste repository for scenarios in
which water contacts the waste. These studies will quantify the magnitude of the
temperature effect on radionuclide solubility (U, Th, Tc, and Cs) and both guide and focus
future performance assessment work.
• Develop a validated coupled process model for disposal in salt for high heat load
wastes. Iterative field observations and model development will lead to a model that can be
used with confidence in future repository design and performance assessment analyses.
• Evaluate environmental conditions post facto. After the heating cycle is complete, the
test will be allowed to cool sufficiently to allow for the performance of forensic studies of the
healed fractures, the consolidated salt, and corrosion coupons as the heaters are
disinterred.
Underlying the research is the hypothesis that heat-generating waste may be advantageous to
permanent disposal in salt. Under the conceptual model leading to this favorable result, the
approximately 300-year thermal pulse introduced by the defense HLW would dry out a moisture
halo around emplaced waste and thereafter accelerate entombment by thermally activating the
creep processes. Note also that the thermally hot UNF recycling fractions (notably cesium (Cs)-
137 and strontium (Sr)-90) will simply decay away in approximately 10 half-lives or 300 years.
Thus, thermal decay storage in salt of these elements, which might otherwise be separated and
stored, would favorably affect the disposal environment for the remaining very long-lived
isotopes. These long-lived isotopes would be permanently encapsulated in a geologic formation
that is demonstrably hydrologically inactive for hundreds of millions of years, thereby potentially
precluding the need for engineered barriers in a repository design. As an example, a currently
proposed engineered barrier is vitrification, a waste form modification for HLW.
The directed research will inform, guide, and ultimately validate capabilities for the next
generation of coupled multiphysics modeling. The current state-of-the-art models will be
instrumental for layout of the large-scale in situ field tests and continue to provide bases for
performance assessment in the future. Next generation coupled TM(H) codes developed
concurrently with the planning phase of the field test would then be bench marked against
current codes and validated using the field test data. This research will identify specific
requirements for a viable long-term decay storage and deep geologic disposal concept in salt.
These key elements would translate into parameters and phenomena to be measured in a
proof-of-principle field test. The validated conceptual and numerical models resulting from the
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effort can then be used in future design calculations or performance assessment analyses.
Appendix B, written as a short memorandum in June 2010, provides a brief recap of some of the
reasons that salt research is timely and of national interest.
The investigators are well aware of the significant challenges to established boundaries
presented in this proposal. The very reason for this proposal is that this work substantially
advances the basis for the design, analysis, and validation of disposal in salt. The work
embodied in this proposal is transformative. It is not proposed to repeat what others have done
before; from the existing body of knowledge, the intent is to push forward the technical basis for
disposal in salt. Cognizance of the scientific baseline has allowed the proposal team to establish
the limits identified in this work, which will further the scientific limits in the address of
unanswered questions. Because this is a science-based research proposal, which explores and
advances the substantial foundation of salt science, the work, by necessity, rests at the forefront
of technology, knowledge, and experience. This work is proposed because it explores the
frontier and addresses questions that when answered, will set the future direction for disposal
options in salt for the nation. Execution of elements of this management proposal, therefore,
presents daunting challenges. Laboratory thermomechanical testing, for example, will include
tests at high temperature and pressure, because understanding the physics under these
conditions is vital to operational concepts, design, safety, and long-term isolation.
One of the important field test design criteria is high thermal loading. If the field test goes
forward at a design thermal load of 40 W/mz, the test bed may experience temperatures in
excess of 16QX in the salt mass (see section 3.4.1), above where most data have been
acquired to date. Steady state creep rate of WIPP horizon salt accelerates one order of
magnitude for each increase of approximately 12°C. The affected salt near the heater is
expected to flow rapidly and perhaps decrepitate. Upon review of the field test plan, the team
may modify the very aggressive temperature limit, decide to modify the test temperature, or
otherwise adjust the test and instrument arrangement. These considerations will be informed
early by the laboratory testing and modeling. Experimentation in the laboratory will also present
significant technical challenges in terms of instrumentation survival and data acquisition. As the
laboratory thermomechanical testing proceeds in advance of the field test, laboratory
experience will greatly inform the field-test team.
Applicability of this proposed work to other salt sites
There is a solid foundation of work conducted in salt, both for thermally cool and thermally hot
wastes, providing confidence that a directed research program could lead to an expeditious path
forward for thermally hot HLW disposal. This foundation, summarized in Hansen and Leigh
(2011) and embodied in the WIPP technical basis documents, consists of 1) WIPP site-specific
characteristics such as the geology of the Salado Formation (the salt host rock for the WIPP
repository), the hydrochemistry of the repository fluids, the hydrogeology of the adjacent
formations, and seismic stability; and 2) fundamental physical processes such as salt creep
behavior, rock salt damage due to the mining operation, the hydrologic characteristics of intact
and damaged salt, the healing of fractures in salt, radionuclide solubility and speciation in high-
ionic-strength solutions, and the ambient-temperature consolidation of crushed salt (studied
extensively in the context of the WIPP shaft seal system design).
At this stage of development of a HLW repository in salt, site-specific considerations in item 1
that enable the WIPP safety case to be made are not relevant because the science gaps being
addressed in this management proposal are basic issues that are independent of any specific
site. However, inasmuch as studies conducted at the WIPP site contribute greatly to the
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foundational knowledge of salt repositories, the rock characteristics and processes studied at
the WIPP site are relevant, especially given that the logistically optimal next step for field testing
would be to conduct in situ experiments at the WIPP facility. Because the location of a future
repository will likely be based on a voluntary siting process (as suggested by MIT, 2011, among
others), science-based investigations conducted before site selection must be focused on
addressing fundamental issues that will be present at any potential salt repository site.
Information gained from in situ studies must be transferable to other sites, either through direct
analogy or through the use of validated numerical models. Furthermore, the observations made
at the specific field study site should provide information useful to the site selection process by
highlighting the properties and conditions that are either conducive or deleterious to repository
performance. In suggesting the need for testing in an underground research laboratory (URL) at
this stage, this proposal draws upon a long precedent in international repository programs (e.g.
IAEA, 2001) for an approach involving research at URLs in advance of or in parallel with a site
selection process, including the Swedish Aspo Hard Rock Site (Lundqvist, 2001) the Grimsel
and Mont Terri sites in Switzerland (McKinley et al., 2001) and the Asse salt mine in Germany;
the wisdom and efficiency of this approach appears to be borne out in the successful progress
of the Swedish program.
With respect to this effort, the proposed research and development will build upon a foundation
of excellence in salt repository applications that began with the 1957 National Academy of
Science recommendation to use salt for permanent isolation of radioactive waste from the
biosphere. As summarized in Table 1-1, various programs at different times and places have
shared their results, which accounts for the large foundation for understanding salt properties
over a wide range of applications. The proposed SDI will further add to the scientific basis for
disposal in salt.
Table 1-1 summarizes the history of in situ salt thermal tests both in the U.S. and internationally
over the past 50 years. The need for additional, science-based testing to fortify the technical
baseline supporting HLW disposal builds upon a considerable data base deriving from historical
experiments. For example, field heater tests in salt were conducted in Project Salt Vault in
Kansas in the 1960s and in WIPP in the 1980s. Building upon past experiences and taking
advantage of advanced technology allow the formulation of a solid, task-oriented, progressive
proposal to address the remaining issues for HLW disposal in salt.
Table 1 -1: Summary of In situ Salt Thermal Tests
Year
Project
Location
Description
1965-1969
Lyons mine, Project Salt
Vault
Lyons, KS
Irradiated fuel & electric
heaters
1968
Asse salt and potash mine
Germany
Electric heaters
1979-1982
Avery Island
Louisiana
Brine migration
1983-1985
Asse (U.S./German
Cooperative)
Germany
Brine migration under heat &
radiation
1984-1994
WIPP
Carlsbad, NM
1) DHLW mockup
2) DHLW over-test
3) Heated axisymmetric
It is worth noting that the heated experiments conducted at WIPP were undertaken after the
agreement was made not to place heat-generating waste at WIPP. The collective science
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community agreed that the results obtained at WIPP would be applicable to the civilian program,
which was investigating salt in the Texas panhandle. Thus, the justification for continuing field
tests at WIPP was recognition of the transferability of information. The basic material properties,
effects of stress and temperature, and phenomenology at a field scale were thought to be
applicable and transferable between sites (see Figure 1-4, for example). In addition, salt
programs have collaborated internationally for the purpose of understanding the fundamental
physics. Indeed, the transferability of salt investigations reaches across the ocean, as the US
civilian program sponsored brine migration experiments at the Asse mine in Germany. The salt
science community has been building the technical baseline collectively for decades, utilizing
lab and field test results from many different sources (Sandia National Laboratories. 2010.
US/German workshop http://www.sandia.gov/SALT/SALT_Home.html.).
The following synopsis includes field experiments that started as early as 1965 with Project Salt
Vault near Lyons, Kansas, as well as nearly contemporaneous field testing and demonstration
at the Asse salt mine in Germany.
In situ field tests to study the effects of HLW in bedded salt were initiated at an underground salt
mine in Lyons, Kansas in 1965. By 1968, elevated-temperature HLW field experiments had
begun at the Asse salt mine in Germany, In situ tests for brine migration resulting from heating
were conducted at the Avery Island salt mine in Louisiana beginning in 1979. Soon after, an
extensive suite of field thermal tests were initiated at the WIPP site near Carlsbad, New Mexico.
Underground tests concentrated on heat dissipation and geomechanical response created by
heat-generating elements placed in salt deposits.
These field tests imparted a relatively modest thermal load in a vertical borehole arrangement
and did not use crushed-salt backfill or explore reconsolidation of salt. These tests were
primarily focused on the mechanical response of the salt under modest heat load. Although the
results can be used, for example, to validate the next-generation high-performance codes over
a portion of the multiphysics functionalities, the SDI disposal concept is intended to explore the
interactions created by higher heat loads, a horizontal placement and crushed-salt backfill. The
Heated Axisymmetric Pillar test conducted at WIPP in the 1980s (Matalucci. 1987) involved an
isolated, cylindrically shaped salt pillar and provided an excellent opportunity to calibrate scale
effects from the laboratory to the field, as well as a convenient configuration for computer model
validation over a small part of the thermomechanical range of interest. These experiments were
conducted at temperatures that are at the lower temperature range than that of which the SDI
investigations are expected to test.
The very concept of analogues for repository performance is predicated on transferability of
information from one site to another. Analogues are used in all geologic repository programs,
regardless of the geology. Considerable qualitative support for permanent isolation in salt
derives from pertinent analogues. For example, the unique sealing capability of salt has been
dramatically demonstrated by containment of nuclear detonations in salt horizons, one at the
Gnome Site near WIPP and two at the Salmon Site at Tatum Dome in Mississippi (Rempe.
1998).
In addition to anthropogenic evidence from mining experience and nuclear detonations, nature
itself showcases the encapsulating ability of salt formations penetrated by high-temperature
magmatic dikes. Salt formations in New Mexico and Germany have been intersected by
magmatic dikes. Despite the severe nature of such magmatic intrusions, there are only very
thin alteration zones at the contact between the high-temperature igneous intrusion and the salt.
No evidence of significant fluid (inclusion) migration toward the heat source has been reported
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from field observations. Analogues over a wide range of conditions provide qualitative evidence
that salt formations have the capacity to permanently contain a wide variety of severe
conditions. This type of analogue information is commonly used in repository sciences and
transferability of such observations is a fundamental tenet of the safety case.
It is for these reasons that SDI investigations, as defined in this management proposal, will
further add to the scientific basis for disposal in salt and that these proposed studies at WIPP
are applicable to other salt sites.
Relationship of this Work to Broader Repository Science Efforts
After the Presidential decision to eliminate Yucca Mountain from consideration as the host site
for a U.S. High-Level waste and spent nuclear fuel repository, the U.S. needs to rethink its
approach to the disposition of defense high-level waste and civilian used nuclear fuel. The
Presidentially appointed Blue Ribbon Commission for America's Nuclear future is chartered to
"conduct a comprehensive review of policies for managing the back end of the nuclear fuel
cycle, including all alternatives for the storage, processing, and disposal of civilian and defense
used nuclear fuel, high-level waste, and materials derived from nuclear activities." (DOE, 2010).
The likely outcome of such an evaluation is a set of recommendations regarding potential
technological and policy alternatives that would provide direction for the U.S. In its efforts to deal
with legacy nuclear waste, hopefully putting the U.S. on a path that enables cleanup of legacy
waste sites and the sustainable utilization of nuclear energy to meet our growing need for low-
carbon energy sources. Thus, there is a need to develop a logical set of research and
development activities, informed by knowledge of the current national need, which would help
the nation to craft a robust repository program. To that end, a set of scientific investigations that
will provide clarity regarding the strengths and limitations of the use of salt as a host medium for
the deep geologic disposal of high-level and other classes of radioactive waste is identified
herein. In reaching this conclusion, no attempt to perform a comprehensive trade study is made,
and it is probable that there are other technically viable choices for permanent geologic disposal
available to the nation. Nonetheless, it is believed that the research program advocated herein,
which proposes to address gaps in the knowledge of the behavior of salt as a disposal medium
for thermally hot waste, represents one promising direction with both near term and long term
benefits.
To understand our long-term perspective, consider Figure 1-5, which illustrates the role of field
tests for model validation in the context of a broader set of investigations required to build a
science-based safety case for disposal. The schematic is generic: it is not specific to any
disposal concept or host medium, nor does it presuppose that a site has been selected for
suitability investigations. The core concept is the systematic reduction of uncertainty in models
through the iterative process of model development, experimental studies, and repository
modeling to assess geologic disposal viability. Separate-effects tests, which typically study one
or a few processes in great detail under controlled conditions, are re-examined in an integrated
fashion in an underground research laboratory (URL), and models of the field test are
developed. No matter how faithful an in situ test is to an actual disposal concept, it is still only a
test of limited duration and spatial extent, rather than an actual repository. Therefore, residual
uncertainties propagated through a generic model of a repository must be quantified, bringing in
other relevant considerations and processes (e.g. scenario development, regulatory criteria,
subsystem models) in order to fully define a Performance Assessment analysis. These results,
vetted at regular intervals with stakeholders, are used to inform modification of the science
program as new knowledge is incorporated and critical uncertainties are identified. Models are
central to this vision, and are used to drive a process of systematic learning, adaptation, and
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communication that is the recommended path to ultimate success of a repository program (e.g.
MAS, 2003). This figure depicts the process at the relatively early stage of development that the
U.S. program currently finds itself, in advance of site selection. As the process evolves, site
screening would be replaced by site-specific investigations, including field tests at a proposed
repository site, PA analyses would no longer be generic, and interactions with stakeholders and
regulators would become more regular and formal.
Figure 1 -5: Conceptual Schematic of Model-Driven Process for Repository Investigations
• FEPs analysis «Test design
• Geologic conditions
• Regulatory criteria
Note: Figure Acronyms: FEPs - Features, Events, and Processes; PA - Performance Assessment; S&T- Science and
Technology; SA - Sensitivity Analysis; UQ- Uncertainty Quantification.
Successful implementation of this process requires a suite of modeling capabilities, from
coupled thermal/mechanical/hydrologic/chemica! process models to higher-level systems
models of repository performance. The current U.S. program, through the Used Fuel Disposition
campaign, has efforts underway to develop repository performance assessment modeling
systems, and general-purpose subsurface modeling and simulation capabilities that will
significantly enhance our capabilities in the future. Meanwhile, a combination of existing codes
and incremental model development will enable us to implement this process.
The understanding of different geologic media and disposal concepts is at different levels of
maturity. In the U.S., salt is one of the most mature, with the iterative loop of Figure 1-5 having
been traversed in the past through the combination of laboratory scale experiments (called
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"separate-effects tests" in the figure), field investigations under ambient conditions, PA modeling
of the WIPP repository, and field-scale heater tests. As opposed to other media and disposal
concepts, the current needs and requirements of a research program for salt are well known
and quite specific, and can be satisfied through an integrated program of laboratory
experiments, model development, and a validation field test to fill gaps in knowledge for
assessing for the disposal concept presented herein. Separate-effects tests include
thermal/mechanical studies on crushed and intact salt to extend the range of temperatures for
which phenomena are known to approximately 300°C, and brine migration, mineral dehydration,
and phase transformation reaction studies to investigate the potential fate of water. Additional
laboratory investigations relevant to repository modeling (i.e. inputs to the "Generic Repository
Models" portion of Figure 1-5) include studies of interactions of fluids with typical engineered
materials at repository temperatures, solubility, speciation, and redox states of key radionuclides
in high-ionic strength solutions at elevated temperatures. In other words, a field-validated
thermal model of salt behavior relies on thermal/mechanical/hydrologic lab studies, whereas the
generic repository modeling performed to put the field results into context for the purpose of
building a repository safety case requires additional data inputs related to radionuclide and
engineered materials behavior in the repository environment.
Armed with this additional suite of separate-effects tests, a thermal test conducted in the field
(represented by the "Field Tests/Model Validation" portion of the figure) is required to complete
another iterative loop of the R&D cycle to reduce uncertainties associated with the disposal of
HLW in salt. To better understand the rationale for this statement, consider that the behavior at
the repository scale is governed by a complex set of interrelated processes at multiple scales.
For example, water movement is tightly coupled to the mechanical behavior of the rock as well
as the thermal evolution of the decay heat in the waste form, crushed salt backfill, and
surrounding salt, both damaged and intact. On the one hand, there is an impressive set of
scientific studies which will be used (and additional laboratory studies are proposed) to
understand the processes that might control the behavior of salt as a disposal medium for
thermally hot waste. However, in the case of repository modeling, different small-scale effects
(each of which are relatively well understood) interact with and influence one another, and their
impacts on large-scale observables wax and wane over time as the system evolves.
Fundamentally, in a complex system, emergent behavior is likely to arise when individual
processes interact in this way. The reductionist approach of studying individual processes or
characteristics of a salt specimen at the laboratory scale is insufficient to allow, for example, the
prediction of the thermal-mechanical evolution of the rock mass and the fate of liberated water.
Only through integrated tests are the operative controlling mechanisms able to be fully
assessed; large scale, in situ measurements in a repository disposal setting are required to
build confidence in a disposal concept, repository design, and safety case.
While the relative merit of conducting this work versus performing R&D in other media is beyond
the scope of this management proposal, these proposed activities fit nicely within the broader
goal of reconsidering multiple options for permanent geologic disposal. The fact that the logical
next step involves field testing is a consequence of the large investments made by the U.S. to
study salt for TRU waste disposal, and previously when salt was considered as a host medium
for HLW before Yucca Mountain was chosen for intensive investigation. Taking an international
perspective to the nuclear waste disposal issue, granite and clay disposal concepts are at a
similar stage of development to salt, in that field investigations are being conducted and generic
and site-specific activities are being pursued, in many cases in advance of site selection. If the
U.S. program follows suit by initiating its own field investigations in salt, and aggressively
pursues international collaborations in salt and other media, ongoing repository science
activities around the world will be maximally exploited the for the purpose of defining future
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options for disposal of U.S. wastes. Furthermore, establishing a U.S.-based URL for repository
science in salt will help facilitate international collaborative R&D, and will maintain and enhance
a critical capability to perform large-scale, subsurface R&D or repository science that was
established in the Yucca Mountain and WIPP projects.
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2. PROJECT MANAGEMENT, QUALITY ASSURANCE, AND SAFETY
2.1. TEST MANAGEMENT STRUCTURE
The overall management of the work proposed within this SDI project will be through the
CBFO. The CBFO defines quality requirements through a QAPD similar to that used for
the WIPP program. The SDI QAPD describes an NQA-1-2008 compliant QA program
for the science-based studies concentrating on high thermal loading effects in bedded
salt. DOE-NE will manage work packages designated in fiscal year 2012 for select
laboratory testing and modeling efforts (see reference 22). DOE-EM is funding efforts
largely related to the planning, design, and initial construction of the in situ thermal test
at WIPP (see Table 4-2 for specific budget breakdown).
LANL-CO will function as the project management organization, responsible for day-to-
day test management and coordination, similar to a successful model used at the
Nevada Test Site and the Yucca Mountain Project, ensuring that all test-related
information and data activities are consistent and focused. In its management capacity,
LANL-CO will report to the CBFO Project Manager. SNL, LANL, and potentially other
scientific entities, will provide Principal Investigators to inform and advise test
management to ensure the testing program is as productive, integrated, and efficient as
can be achieved. Those portions of the SDI investigations funded by Used Fuel
Disposition Campaign (UFDC) of the DOE-NE will be managed according to the
judgment of the UFDC management team.
WTS, the WIPP Management and Operating Contractor, will provide engineering,
construction, and test support labor to provide for the test bed (e.g., drift mining,
borehole coring, electrical, and ventilation) and aid in test installation.
Participants in this research will include personnel from LANL, SNL, and WTS.
Personnel at these organizations bring many years of direct salt repository experience
and have conducted decades of salt research and thermal testing, both in the laboratory
and the field. Experience directly relative to the types of field and laboratory activities
described in this management proposal include field work at the Nevada Test Site, large
in situ thermal tests at Yucca Mountain Nevada, and experimentation at WIPP.
Additionally, the primary collaborators bring the experience of many years of public
interactions, which sharpen an appreciation for public understanding. Public outreach
will be integrated with our international collaborators and build upon elements of their
success as well. Appendix C provides a list of key contributors to this management
proposal and a summary of related experience. Figure 2-1 illustrates the organizational
structure of this testing program with the funding partnership between DOE-EM and
DOE-NE.
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Figure 2-1: SDI Organizational Structure with Funding Partnership
- Sandia National Laboratories ~
- Los Alamos National Laboratory j
¦ Other Labs and Contractors f
I * Fur ding Partners
2.2. QUALITY ASSURANCE AND SAFETY
CBFO, in support of this project, developed an SDI QAPD modeled after the highly
effective and time-proven CBFO QAPD. The SDI QAPD describes an NQA-1-2008
compliant Quality Assurance Program for the science-based studies concentrating on
high thermal loading effects in bedded salt. Existing WIPP procedures are adapted as
appropriate to accommodate the SDI program, thereby taking advantage of the existing
mature and audit-tested programmatic and technical processes established for the
repository program.
Each program participant assigned responsibility for performing the SDI work described
in this proposal (primarily LANL, SNL, and WTS) is currently working under and
maintaining compliance with the CBFO QAPD for WIPP activities. The CBFO, for
current WIPP work, is responsible for defining quality requirements and applicability,
developing appropriate plans and procedures to attain quality, and supporting project
participants in pursuit of quality. Where applicable, project participants are responsible
for developing and following plans and procedures that effectively implement the
requirements described in the CBFO QAPD. Project participants are also responsible
for compliance with requirements contained in other relevant CBFO planning
documents. Those elements of the SDI funded by DOE-NE will be performed consistent
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with requirements of the Fuel Cycle Technology QAPD, which governs Quality
Assurance for research under DOE-NE.
The combined experience and track record of the national laboratories, WTS, and CBFO
in successful implementation of rigorous QA programs in a regulatory environment are
exceptional. The primary national laboratories expected to participate in this work (LANL
and SNL) have extensive NQA-1 experience in repository sciences associated with
WIPP. Each has participated in the successful compliance certification (and two 5-year
recertifications) of WIPP with the U.S. Environmental Protection Agency (EPA) as a
regulator and the Resource Conservation and Recovery Act (RCRA) permit issuance
and recent 10-year renewal by the New Mexico Environment Department (NMED).
Additionally, as with quality assurance, each proposal participant has extensive
experience and an exemplary record of safety related to field and laboratory work
activities, including a culture and value structure that promotes safety in the workplace.
Each listed participant will conduct work safely and responsibly; ensure a safe and
healthful working environment for workers, contractors, visitors, and other on-site
personnel; and protect the health, safety, and welfare of the general public. This is done
through institutional frameworks and processes that align with the principles and
functions of Integrated Safety Management.
2.3. WIPP REGULATORY COMPLIANCE CONSIDERATIONS
The WIPP may only dispose of the nation's defense-related transuranic radioactive
waste, however, there are processes to evaluate the use of WIPP for underground
experiments. The use of the WIPP underground for the field test portion of SDI is based
on saving costs by avoiding the development and installation of mining infrastructure at
some other existing salt or potash mine of similar depth. There will be some costs to
perform the tests in WIPP. However, the area to the north of the access shafts (and far
north of waste disposal operations) is already configured with electrical power and fiber
optic cable to service basic science experiments. An existing trained workforce, mining
infrastructure, nuclear safety bases, and an NQA-1 quality assurance program already in
place will make the field test part of SDI cost less than bringing these essential elements
of a field test to another commercial mine.
The cost effective and efficient use of WIPP for the field tests is offset by the need to
gain regulatory approval to conduct the tests there. WIPP's compliance envelope is
complex, with multiple state and federal agencies involved. The two most important
regulators that are involved in WIPP operations are the NMED and the EPA. In addition,
DOE itself must ensure that any tests performed at WIPP are in compliance with the
National Environmental Protection Act (NEPA).
In response to multiple basic science inquiries made by researchers across the country
after WIPP opened, DOE conducted an Environmental Assessment (EA) under NEPA
guidelines in 2001. That EA analyzed impacts from a variety of possible experiments
that might be performed using the unique underground setting at WIPP. One of the
bounding experiments was a test very similar to the scope of the proposed SDI. That
potential experiment involved using electrical heaters in specially mined alcoves to
measure the response of the salt medium to the effects of heat-generating materials
emplaced for disposal in salt. A Finding of No Significant Impact (FONSI) was reached
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as a result of the EA, and this management proposal assumes that no additional
analyses are necessary under NEPA to allow the SDI field tests to be performed in
WIPP (Marcinowski to Triay. 2003).
The NMED regulates the disposal of hazardous waste at WIPP under the provisions of
the RCRA. Much of the transuranic waste destined for disposal in WIPP also contains
hazardous components regulated under RCRA. However, none of the specific actions
proposed in the SDI field test will involve hazardous materials. Therefore, no
modification of the permit issued to WIPP by NMED should be necessary. However,
since the SDI tests will use the common infrastructure that is regulated under the permit
for waste disposal, DOE will inform and consult with NMED as the tests are designed
and conducted.
WIPP's primary purpose is the permanent isolation of transuranic waste resulting from
defense activities. EPA's regulations promulgated under 40 Code of Federal
Regulations (CFR) Parts 191 and 194 require that DOE ensure isolation and compliance
with the standards for a 10,000-year period. The conduct of SDI field test is unrelated to
waste emplacement operations (other than the use of common infrastructure) and will
not change the characteristics of the overall disposal system within the land withdrawal
area for WIPP. DOE will prepare analyses that demonstrate the effects of the additional
mining and heating of the test area footprint (well north of the waste disposal operations)
will not compromise long-term repository performance. These analyses will be
submitted to EPA under a Planned Change Notice for their review and concurrence,
similar to the process both agencies have successfully used for other basic science
experiments that have been, and continue to be, conducted in the north part of the WIPP
underground. This review and approval process has typically required about 3-6 months
to complete and will be initiated in mid FY 2011 to support the start of mining.
2.4. INTERNATIONAL COLLABORATION
CBFO will establish a program that will re-engage research and operating entities in
Germany and other European Union (EU) member nations. This proactive re-
engagement with primarily European counterparts will enhance the DOE's scientific
program and protect against loss of knowledge and personnel from salt repository
enterprises. Elements of the international outreach will provide consistent support for
workshops devoted to repository research topics, which will provide a forum for
documenting technical advances that accompany an expanded publication effort.
Salt disposal remains a leading permanent disposal option and it is well established
internationally. (Sandia National Laboratories. 2010. US/German Workshop on Salt
Repository Research, Design, and Operation, May 25-27, 2010.
). As one of the most advanced
repository options in the world, the science community has a definitive grasp of what has
been done and what still needs to be done. Much of the experience gained from United
States repository development, such as seal system design, coupled process simulation,
and application of performance assessment methodology, helps define a clear strategy
for a heat-generating nuclear waste repository in salt. The authors worked closely with
German salt repository scientists and engineers to identify the research challenges
ahead of us.
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The recent summary of the US/Germany workshop proceedings issued by
Forschungszentrum Karlsruhe GmBH (KIT. 2010) acknowledges that implementation of
a repository for heat-generating waste in rock salt is feasible. This German agency
supports research and development in rock salt that parallels the work identified in this
proposal. Full-scale field studies in the United States include Project Salt Vault at Lyons,
Kansas; the Avery Island, Louisiana, heater tests; and WIPP thermal structural
investigations. Salt repository programs in Germany include a proposed HLW site at
Gorleben, the research facility at the Asse Mine, the nuclear waste storage facility at
Morsleben, and a bedded salt storage facility for chemotoxic wastes at Herfe-Nerode. In
today's environment, large-scale salt studies have been pursued by EU members.
Collaboration with EU countries (with Germany, in particular) would avail technical staff
of the latest international developments in salt repository sciences. Possible goals for
international collaboration include:
• Create collaboration and technical alliances between CBFO and international
partners (first Germany, then other EU member nations).
• Preserve and advance technical applications of salt sciences, specifically focusing
on international interests that compliment U.S. interests.
• Perform fundamental research into areas where understanding deformational
behavior of salt is incomplete.
• Partner with EU countries (Germany and Poland as a start), through the Nuclear
Energy Agency of the Organisation for Economic Co-operation and Development, to
support a working group on "Safe Disposal of Long-Lived Radioactive Waste in Rock
Salt as Repository Host Rock Formation" (Salt Club).
• Develop position papers on vital salt repository issues, such as brine and vapor
transport.
• Utilize technology and instrumentation developed and demonstrated in salt
applications in Europe.
• Provide an educational basis for and knowledge transfer to next-generation
researchers.
• Transfer methods and tools for salt storage facilities and mining operations to ensure
safe, secure, long-term functionality of the underground structures.
• Expand existing international collaboration with Karlsruhe/INE on actinide speciation
in brine.
• Make technology available to support the nation's future energy supply and
infrastructure needs.
• Afford technical experts access to the latest international developments in salt
mechanics sciences.
• Develop a central library of acquired salt data and other information, with broad
access provided via the Internet.
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3. PROPOSED RESEARCH PROGRAM
The proposed research program describes areas that would substantially enhance our
knowledge of the behavior of thermally and radioactively hot nuclear waste in salt and would
provide fundamental data for the evaluation of concepts for disposal in salt. The program has
been divided into the following major elements:
1. Functional and Operating Requirements and Test Planning {including Project Management,
QA, Safety and Regulatory Compliance activities as described In section 2.0)
2. Laboratory Thermal and Mechanical Studies to Support the Field Test
3. Laboratory Hydrologlc, Chemical, and Material Studies
4. Coupled Process Modeling
5. Field Test Installation and Operation
6. International Collaboration (described in section 2.4)
The first task establishes the functional and operational requirements for the field test. The
experimental investigations are divided into laboratory testing, modeling, and in situ testing.
Laboratory research in support of the field test includes thermomechanical and hydrologic
testing of intact and crushed salt and chemical and physical properties of the brine as a function
of temperature. Chemical and material studies consistent with salt repository performance will
also be pursued in the laboratory. Some of these areas received a considerable amount of
attention in the 1960s to 1990s; however, the upper temperature limit for the thermomechanical
intact salt tests has been about 200°C, and crushed salt and chemical interaction tests were
predominantly conducted at room temperature. The laboratory studies will build upon previous
work and enhance these efforts by reinvi go rating international collaborative research.
Furthermore, the proactive reengagement with primarily European counterparts will enhance
our scientific program and protect against loss of knowledge and personnel from salt repository
enterprises. A carefully designed field test in bedded salt will serve as a proving ground for
concepts of disposal in salt and provide data for modeling validation and refinement that is
needed for a repository design or performance assessment model. The in situ heater test in out
years will provide a full-scale mock-up of a generic salt repository design concept and will
provide data (temperature, deformation, and environment) for thermomechanicat calculation
confirmation, backfill consolidation, moisture movement, and waste form/brine chemical
interactions. Forensic analyses of the re-mined material after the in situ heater test will provide
performance validation and confirmation in years beyond the current proposal. All of this
information will be used to support an integrated modeling and simulation effort for the
evaluation of concepts for disposal in salt.
Elements of this management proposal are technically integrated and build a solid science basis
for disposal options. The proposed testing and modeling will be conducted under a QA
program. The QA obligation includes development of test plans, calibrations, and record
capture and storage.
3.1. FUNCTIONAL AND OPERATIONAL REQUIREMENTS AND TEST PLANNING
This task will be determining F&OR for a field test. CBFO will collaborate with the
technical team in the development of the F&OR, as well as assuring the appropriate
breadth of scientific studies is included. The F&OR document will be a deliverable to
CBFO in late FY 2011 and will be used to provide the basis for the test bed location,
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layout, and operational requirements such as specifics related to providing proper
ventilation, power, and access. Test-specific requirements such as instrumentation
characteristics, precise borehole placement, instrumentation calibration requirements,
data quality objectives, and other detailed test information will be provided in a field test
plan to be developed, reviewed, and delivered in FY 2012. Laboratory testing and
modeling activities will have specific test plans scaled to the level of activity complexity,
in accordance with the applicable QAPD. As part of these detailed test plans, existing
and available information from past thermal experiments in salt will be comprehensively
evaluated.
3.2. LABORATORY THERMAL AND MECHANICAL STUDIES
Laboratory studies of salt are proposed and described in the following sections. The
laboratory studies are intimately related to the needs of the modeling program.
Experiments to evaluate consolidation of hot, dry, run-of-mine salt, will yield a
stress/temperature/porosity function needed for modeling the disposal proof of principle.
In addition, an assessment of thermal conductivity as a function of porosity is needed to
properly account for the transient evolution of the disposal area. Deformational
phenomenology of exceptionally hot intact salt tested uniaxially is fundamentally
important before the final design parameters are assigned for the disposal concept field
test. These thermomechanical (TM) laboratory results are essential for modeling and
therefore need to be conducted as early in the program as possible. These TM inputs
are used directly for modeling the proof-of-principle disposal concept, which includes
liberation of accessible brine.
Laboratory studies on WIPP salt are designed to provide a phenomenological
examination of intact salt at high temperatures and stress states that the near-field salt is
expected to experience. Consolidation of hot, dry crushed salt will provide important
data for performance and detailed modeling of the disposal concept. Salt immediately
surrounding a simulated waste package (heater) will consist of run-of-the-mine salt
(backfill) used to bury the heater. Both laboratory experimental programs involve
mechanical compression at temperatures as high as 200°C to 300°C to observe the
change in deformational behavior as the temperature increases. Earlier Office of
Nuclear Waste Isolation (ONWI) and WIPP experience and knowledge of salt's
thermomechanical response provide an initial basis for this applied rock mechanics
work. The personnel performing these studies will share information with international
collaborators.
For purposes of the field test, it is anticipated that the underground salt environment will
be heated to temperatures well above those for which current salt experimental data
exist. In a general sense, the thermally driven response of salt is the controlling element
of the concept of disposal in salt. Elevated salt temperatures will cause accelerated salt-
creep deformation, which leads to a more rapid encapsulation of the waste. Therefore,
these laboratory-based intact-salt studies will provide key field-test information for
evaluating the disposal concept and testing the hypothesis that the thermal pulse
imparted by the waste leads to this rapid encapsulation.
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Figure 3-1: Strong Influence of Temperature on Creep of Natural Rock Salt
Time, days
Salt deformation is dominated by plastic behavior at elevated temperatures. Figure 3-1
illustrates strain-versus-time curves for creep tests on rock salt performed at the same
stress condition but at different temperatures, Temperature has a dramatic influence on
the creep rate of intact salt specimens owing to thermally activated deformation
mechanisms. Relatively little elevated temperature mechanical testing has been
conducted for crushed salt consolidation, an important element of the concept of
disposal in salt, Crushed salt testing has two parts. First consolidation testing will derive
a relationship between temperature, stress states and porosity. The second test series
wiil determine thermal conductivity as a function of porosity and temperature.
3.2.1. Intact Salt Studies
All testing will be performed under an approved test plan developed in accordance with
appropriate QA requirements discussed earlier in this management proposal. A
preliminary test matrix is identified here for schedule and cost estimates, Test conditions
described push the threshold of laboratory experience on natural salt. The Principal
Investigator will reserve flexibility in the test plan to change the preliminary test
conditions if results warrant it. The intact salt will be tested in an unconfined condition at
a constant axial strain rate using solid cylinders. Uniaxial stress loading will continue
until the specimen exhibits either failure or extreme deformation (-20% strain). It is well
known that salt deformation, even at room temperature, is dominated by plastic
deformation mechanisms. Crystal plasticity will be greatly enhanced as temperature
increases, such that extensive plastic deformation will accompany fracture formation. As
a preliminary basis of estimate, a total of nine tests {Table 3-1) will be conducted
comprising a triplet of tests at each of three temperatures: 2Q0°C, 250°C, and 300°C.
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Inelastic creep processes will dominate the deformation of the specimens even in a
quasi-static load application, with the creep response being ever more pronounced as
the temperature increases. Rather than specimen failure, extreme deformation is
expected to cause the tests to be stopped.
Table 3-1: Uniaxial Compression Test Matrix
Test
Number
Salt Type
Test Type
Temperature
Loading Condition
9,10,11
Intact
Uniaxial stress
200°C
Constant Strain Rate
12,13,14
Intact
Uniaxial stress
250°C
Constant Strain Rate
15,16,17
Intact
Uniaxial stress
300°C
Constant Strain Rate
The tests at 200°C will overlap with historical databases and provide a point where
predictive models based on those databases can be checked for the current work. The
tests at temperatures above 200°C will provide new data so that extrapolation outside
the actual test database will not be necessary. The field test (and actual alcove
disposal) is expected to involve temperatures much greater than 2G0°C (at the heaters),
thus this high-temperature research is needed for the design and evaluation of the in situ
experiment. An assessment of the need to run triaxial experiments at these
temperatures will be made based on the results of these uniaxial tests. The schedule
and budget do not include triaxial testing.
3.2.2. Crushed Salt Studies
The laboratory tests on crushed salt include consolidation as a function of stress and
temperature and thermal conductivity as a function of bulk density and temperature.
Here "crushed" salt means run-of-mine salt that is sieved to separate out large
aggregate. Consolidation of the sieved run-of-min salt can be performed in two ways:
either using an oedometer arrangement or an isostatic pressure vessel. Thermal
conductivity of the backfill salt will be measured on reconsolidated salt specimens
produced during the consolidation studies. The thermal properties will be measured
over a temperature range from the mine temperature to 300°C and at a variety of
porosities.
Because of greater opportunity for experimental control, most consolidation research will
be done using an oedometer. Oedometer consolidation involves uniaxial compression
of circumferentially constrained granular salt within a hollow steel shell. The large scale
apparatus for consolidation under heat and load will have to be fabricated. Consolidation
is measured using axial displacement measurements, and the measured change in
volume represents the reduction of pore space in the run-of-mine salt and an
accompanying increase in bulk or fractional density. A total of eight individual tests (as
listed in Table 3-2) are proposed. Two replicates will be performed at each of four
temperatures: 100°C, 150°C, 200°C, and 250°C. The stress application and
deformation of these tests is expected to be short term; however, the pre-test heating
and the post-test observational work (petrographic analyses) will require additional time.
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Table 3-2: Oedometer Consolidation Test Matrix
Test
Number
Salt Type
Test Type
Temperature
Loading Condition
1,2
Backfill
Uniaxial compaction
100°C
Biaxial Stress
3,4
Backfill
Uniaxial compaction
150°C
Biaxial Stress
5,6
Backfill
Uniaxial compaction
200°C
Biaxial Stress
7,8
Backfill
Uniaxial compaction
250°C
Biaxial Stress
The consolidation of granular salt will also be examined using hydrostatic (uniform
triaxial) compression. In this style of testing, stress control is provided by two
independent systems: an axial loading ram and fluid pressure applied radially to the
specimen. The loading ram is a standard hydraulic actuator driven by a servo valve, and
either the ram position or the load on the ram can be used as the feedback control
variable. Fluid pressure in the vessel is controlled by a constant-pressure intensifier,
which also functions as a dilatometer, making it possible to measure volume changes of
samples.
The isostatic compression method can be modified to produce deviatoric compression
where the axial and confining pressures are not equal. This test condition is a more
realistic representation of the consolidation expected in alcove disposal, where the roof-
to-floor closure is expected to be faster than the rib-to-rib closure. A series of deviatoric
consolidation tests will be performed to compare to the isostatic and oedometer
consolidation results.
Thermal conductivity tests will be performed over a temperature range from room
temperature to 300°C at known values of fractional density (porosity). The specimens
for the thermal conductivity tests will be created in a manner similar to the way uniaxial
consolidation tests are conducted. The major difference in the thermal conductivity
specimen creation test will be that the test will be terminated at specific targeted values
of fractional density. Additionally, the specimens might have to be sized differently than
the mechanical test specimens for thermal conductivity test purposes.
The thermal conductivity test method will most likely be the comparative cut-bar method
(ASTM E1225, Standard Test Method for Thermal Conductivity of Solids by Means of
the Guarded-Comparative-Longitudinal Heat Flow Technique) to measure axial thermal
conductivity. In this test, the crushed salt specimen is placed between two sections of a
material with known thermal properties, and then a heat flux is passed through the
assembly. Comparison of the temperature gradients is then used to determine the
thermal conductivity of the test specimen. Depending on specimen size requirements
for run-of-the-mine crushed salt and the anticipated relatively low values of thermal
conductivity compared to the value for intact salt, the guarded hot plate method (ASTM
C177, Standard Test Method for Steady-State Heat Flux Measurements and Thermal
Transmission Properties by Means of the Guarded-Hot-Plate Apparatus) may be used
for some crushed salt thermal conductivity measurements. This method is more
commonly used for materials requiring large specimen sizes with low thermal
conductivity values.
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The individual thermal conductivity tests to be performed in this initial laboratory effort
are outlined in Table 3-3. The tests will be conducted on a range of porosity values from
35% (estimated mine-run value) to porosities approaching those of intact salt. The
thermal conductivities will be determined at average specimen temperatures of mine
temperature, and at 50°C degree increments from 100 to 300°C — shown as 25°C-
300°C in Table 3-3.
Table 3-3: Thermal Conductivity Test Matrix
Test
Number
Salt
Type
Test Type
Porosity
<%>
Six
Temperatures
1-6
Backfill
Steady-Flow Conductivity
35
25°C-300°C
7-12
Backfill
Steady-Flow Conductivity
30
25°C-300°C
13-18
Backfill
Steady-Flow Conductivity
25
25°C-300°C
19-24
Backfill
Steady-Flow Conductivity
20
25°C-300°C
25-30
Backfill
Steady-Flow Conductivity
15
25°C-300°C
31-36
Backfill
Steady-Flow Conductivity
10
25°C-300°C
37—42
Backfill
Steady-Flow Conductivity
5
25°C-300°C
43—48
Backfill
Steady-Flow Conductivity
~1
25°C-300°C
Design, development, fabrication, and qualification of test equipment and techniques are
included in the estimates found in Table 4-1. Each testing program would be conducted
under a reviewed and approved test plan. Test conditions may be changed by the
Principal Investigator as research progresses; however, the test matrix provided
sufficiently defines the research effort for proposal purposes.
3.3. LABORATORY HYDROLOGIC, CHEMICAL, AND MATERIAL STUDIES
During the field test, it is anticipated that the underground salt environment will be
heated to temperatures for which current experimental data do not exist. Two
interrelated components of the system involve the nature and fate of brine as well as the
geochemical interactions of the salt/brine/engineered materia Is/radioactive waste.
Understanding the mobilization of native brine is essential to establish the evolution of
the underground setting of the disposal concept. Migration of small amounts of water
present in fluid inclusions within the intact salt, as well as the potential liberation and
transport of brine derived from dehydration of hydrous minerals within the interbeds of a
halite deposit, must be characterized in order to assess such parameters as the basic
amount of brine available to the system and its ability to influence deformational
processes such as fracture healing and granular salt consolidation. In addition, as the
potential carrier of radionuclides, the brine source and transport represent essential
components of the repository source term for scenarios in which brine-waste interactions
are evaluated.
Closely related to the source and transport of brine is the chemical and material behavior
of the brine/saIt/engineered materials/waste form system. Laboratory studies on salt and
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brine will build upon the scientific basis developed for WIPP, and bounding brine and salt
formulations will establish the key factors that control radionuclide solubility and mobility
at elevated temperatures (as discussed in the chemistry sections of this proposal). The
data obtained will be used to fill knowledge gaps in models for radionuclide release for
the range of hypothesized intrusion conditions that could be encountered in the disposal
of thermally hot waste (such as EM defense HLW) in a salt repository. In addition,
material interaction data from both the laboratory studies and the field test site will be
analyzed, providing data that could be used to assess the compatibility of various waste
forms, if warranted.
The next two subsections present the laboratory brine liberation/migration tests and
chemical/material studies proposed to fill gaps in data needed to support the field test
and model development. In each area, a detailed test plan will be written, reviewed, and
approved prior to initiating the laboratory experiments. Thus the concepts put forward
below are consistent with the science basis for disposal in salt and will be rigorously
reviewed in the process of implementation.
3.3.1. Hydro logic Studies
The foundational data needed to assess the sources, rates, and migration mechanisms
for brine fall into two categories: brine migration in intact (or dilated) salt, and water
liberation from accessible brine, such as hydrous minerals or grain boundary brine.
These two experimental investigations are detailed below.
Brine Migration
The fate of water trapped as inclusions within salt crystals and in hydrous minerals
present along with the halite is important to understand when assessing performance of
a salt repository. Typical quantities of water present in salt fluid inclusions is on the order
of 0.1 to 1% in bedded salt (e.g. Permian salt from the WIPP site ranged from <0.1%
and 1.7% and is highly spatially variable - Roedder and Belkin, 1979a), and much lower
in domal salts (e.g. on the order of 0.003% in several Louisiana salt domes - Knauth
and Kumar, 1981; Knauth et al., 1980). Historically, fluid inclusions in salt have been
used forensically to study the paleoenvironments relevant to the location of petroleum
reservoirs. Pursuit of the concept of using salt for nuclear waste disposal led to a series
of investigations employing fluid inclusions in geologic studies to shed light on the
environment and subsequent evolution of the salt deposit, as well as to consider the
possibility that this water might negatively impact repository performance (Roedder,
1984). A recognized and well-studied mechanism by which salt can potentially migrate
up a temperature gradient toward the nuclear waste canister is the process of dissolution
of salt on the high-temperature side of the inclusion, solute diffusion within the fluid to
the low-temperature side, where deposition occurs from the supersaturated solution. The
net effect of this process is migration of the inclusion from lower to higher temperatures.
If significant water contacts the waste canisters, corrosion could occur, including the
possibility of exposing the waste to direct contact by water should a portion of the
repository later become inundated due to natural processes, failure of repository seals,
or an inadvertent human intrusion episode. Beyond these potential failure mechanisms,
the role of water in facilitating fracture healing must be understood in order to predict the
evolution of permeability and rock deformation properties in the DRZ. Relatively steep
gradients of the order of 2°C/cm or higher are required to mobilize fluid inclusions in salt.
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U.S. Geological Survey (USGS) experiments (Roedder and Belkin, 1979; 1980) indicate
that an increase in ambient temperature and/or gradient increased the inclusion
mobilization rate, in approximately direct proportion. The migration rates for inclusions in
different parts of a given sample, however, were found to vary by a factor of three, for as
yet unknown reasons. The three major controlling variables seem to be inclusion size,
ambient temperature, and temperature gradient. Theoretical considerations and some
experimental studies suggest that the migration rate may also be related to the fluid
composition, the presence (and volume) of a gas bubble, the gas pressure in such a
bubble, mechanical strain in the host salt, dislocation abundance and nature, and
crystal log raphic direction.
While numerous laboratory studies have been performed to investigate the mechanisms
by which fluid might mobilize and contact waste canisters, significant uncertainties
remain. The details of movement of fluid inclusions even within a single salt crystal are
very complex, depending on temperature gradient, inclusion size and shape, the
presence or absence of a gas bubble, stress, and surface tension effects within the
inclusion (see Carter and Hansen, 1980 for a summary discussion). Furthermore, the
fate of brine at grain boundaries is also complex and variable: in many cases, migration
of inclusions is observed to cease at grain boundaries, with the fluid spreading into
microcracks at the boundary. However, in some instances, the inclusion is observed to
traverse the grain boundary (Jenks and Claiborne, 1980) and continue to migrate within
the adjacent grain. Decrepitation has also been observed to liberate relatively large
quantities of water from inclusions (Roedder and Belkin, 1979a). As temperature rises,
water from either inclusions or mineral dehydration reactions that is present in
microcracks and other discontinuities in the rock mass will tend to be mobilized through
vapor transport, at rates that are proportional to the permeability of the fractured salt
medium. This permeability will, for some period of time, be orders of magnitude higher
than that of intact salt; it will exhibit directional dependence (e.g. Beauheim and Roberts,
2002); it will depend on distance from the mined opening (Hansen and Leigh, 2011); and
it will vary in time as fractures undergo stress-induced healing (Pfeifle and Hurtato,
1998). The nature of this interplay of various processes is currently unknown and
requires further study, starting with laboratory tests and progressing to examination of
the integrated effects in the field.
To perform these essential experiments, these rather extreme conditions shall be
examined in the laboratory by way of some innovative tests on both natural intact and
disturbed salt. Laboratory thermal gradient testing could address the possibility for brine
migration with the following approach: 1) impose a thermal gradient on natural salt cores
(both intact cores and with a mechanically stressed zone within the core) to promote
brine migration and 2) allow liberation of brine from the core as a function of stress state
and deformation. There are several important aspects to this approach. First, the
temperature and stress states could be controlled independently, starting with a
temperature gradient and no applied stresses. Observational microscopy could
document fluid inclusion migration relative to the gradient and grain boundaries. Second,
an appropriate stress state could be imposed while thermal gradients are maintained. In
both cases, the liberation of moisture will be estimated from both weight loss and fluid
capture, while the phenomenology of brine inclusion migration will be documented using
microscopy techniques. The fundamentals of brine migration and vapor transport,
especially at the intact/disturbed rock zone interface, are identified as central to building
the case for disposal in salt. Brine migration studies will be reinitiated in the laboratory
for a specific range of conditions diverse set of conditions (temperatures, gradients, and
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levels of damage, which will be measured as volumetric strain) in order to further
develop the conceptual model for brine migration behavior,
Clav Dehydration and Phase Transformation Studies
Hydrous minerals, in particular clay, produce the most brine at WIPP. Clay interbeds in
the Salado Formation (repository layered salt horizon at WIPP) can attain a thickness of
up to one meter. Therefore, in the process of the thermal gradient testing described
above, the weight loss of the clays will be examined specifically. Clays (smectite/i11ite
layered phyllosilicates) are important in a repository environment as their volumes, water
contents and stability can be affected by even small variations in temperature and partial
water pressure, thereby resulting in changes in water amount in the environment and
potentially in the host rock strength, porosity and permeability. In a repository,
emplacement of waste will increase temperature and thus will change the water vapor
pressure. In such a geological system, the partial water pressure is typically lower than
the total pressure and dehydration of clays might occur below the boiling point of water
(Koster van Groos and Guggenheim. 1986). Different behaviors are expected
depending on whether the rocks are unsaturated (disturbed salt) or saturated (intact
salt).
The thermal behavior of clays may involve several phenomena: 1) reversible
collapse/expansion of the smectite layers due to loss/gain of interlayer water at water
vapor pressures < 1 atm (Wu, et al. 1997); 2) irreversible collapse of the smectite layers
due to loss of interlayer water and migration of interlayer cations into the layers
(Meunier, et al. 1998); 3) irreversible reduction of the osmotic swelling capacity of
smectites in a steam atmosphere (Koster van Groos and Guggenheim. 1986); and 4)
inhomogeneous transformation of smectites into interstratified illites/smectites at
temperatures > 300 °C (Mosser-Ruck et al. 2010). Of these four types of thermal
reactions, reversible collapse and collapse in a steam environment probably play more
important roles in a repository environment. Such dehydrations may create transport
pathways as those volume contractions are accommodated under in situ conditions.
For clay dehydration, because there are gaps and discrepancies in experimental data,
the partial dehydration of clays over the relevant temperature and partial water pressure
range will be quantified, clay phases analyzed and characterized, and the potential
impact on the water source term and stability of the altered minerals assessed. Along
with geochemical modeling and thermodynamic constraints (Vidal and Dubacq. 2009),
the phase transition from smectite to illite will be mapped out in repository P, T space.
Because data will be provided from basic measurements and to close gaps in
knowledge, the data would then be incorporated in coupled THMC models to properly
account for the impact of these mineral reactions on water liberation and migration. The
high pressure experimental lab at LANL {presently performing research on geothermal
tracers, carbon sequestration, and natural analogue nuclear waste forms) is well suited
to perform such experiments in Dickenson autoclaves and cold seal assemblies at
potential repository maximum temperatures (350°C) and lithostatic pressures (600 bar).
Furthermore, the LANL experimental lab is now certified to the new DOE pressure
standards.
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3.3.2. Chemical and Material Studies
This overall approach encompasses experiments and fundamental research that identify
and analyze the components and characteristics of the waste that could impact
repository performance. The work will be divided into five tasks:
1. Measure the thermodynamic properties of brines and minerals at elevated
temperatures. Precise measurements of the pressure, volume, and temperature
(PVT) properties of brines are required for hydrologic and chemical benchmark
modeling and future development of performance assessment models.
2. Study repository interactions with waste container and constituent materials.
Evaluation of the chemical interactions of a broad range of materials and waste
forms with a salt-based repository will provide a scientific basis to evaluate waste
form strategies and engineer waste forms and packages.
3. Measure the effect of elevated temperature and Ionizing radiation on brine
chemistry. The results of these experiments will bracket the potential changes in
brine chemistry due to temperature and radiolysis, as well as provide a measure of
the extent that these changes are controlled by waste package constituents.
4. Measure the effect of temperature on radionuclide solubility In brine.
Radionuclide solubility will determine the source term of any thermally hot waste
repository for scenarios in which brine contacts the waste. These studies will
quantify the magnitude of the temperature effect on radionuclide solubility in brine
and both guide and focus future performance assessment work.
5. Measure radionuclide oxidation distribution and redox control at elevated
temperatures. The lower oxidation states of key radionuclides (U(IV) and Tc(IV))
will be less soluble, and it is important to establish the effects of elevated
temperature and ionizing radiation on the processes that generally lead to the
creation of a reducing environment in a salt repository.
The motivation for these tasks is discussed in more detail below. Details regarding the
laboratory apparatus, experimental techniques, and ES&H requirements will be
described fully in detailed test plans written upon commencement of the laboratory
testing program.
3.3.3. Measure the Thermodynamic Properties of the Brines and Minerals at Elevated
Temperatures
PVT properties of brines are required for both radionuclide source term model and
benchmark model development. Precise, specific heat capacities of brines from the site
are required to predict the thermal history of brines according to different thermal loading
scenarios. These properties for complex brines are not available in the literature. To
determine the range of conditions under which thermodynamic properties are required,
both undisturbed conditions in which the intact salt is under lithostatic load will be
considered, and disturbed conditions in which the presence of the mined opening or, for
example, a borehole being inadvertently drilled through the repository, will be
considered. Under the undisturbed scenario, the lithostatic pressure (brine pore
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pressure) for a salt repository at a depth of 650 meters is about 15 megapascals (MPa).
In such a case, the pressures for the brines at elevated temperatures will be dominated
by the brine pore pressures. Under the disturbed scenarios, the pressures for the brines
at elevated temperatures will be the saturated vapor pressures, which are a function of
both temperature and brine composition.
For purposes of this management proposal, the host rock is the Salado Formation. The
following tests will be performed on samples from the Salado Formation:
1. Determine the saturated vapor pressure of brine in equilibrium with halite-
polyhalite-anhydrite at temperatures up to 300°C. Saturated vapor pressures of
complex brines at elevated temperatures are not known. This property is important
for calculating the pressure dependence of chemical equilibrium.
2. Determine the PVT properties of brines up to 300°C at constant pressures (1 to
20 MPa) and saturated vapor pressures. The ultimate goal of this subtask is to
produce adequate experimental data to develop equations of state for brines.
3. Determine viscosity and thermal conductivity of brines up to 300°C, These fluid
properties will affect the heat and mass transport processes affecting brine
movement at the pore scale, and therefore must be known under a wide range of
conditions.
3.3.4. Study Interactions with Waste Container and Constituent Materials at Elevated
Temperatures
Laboratory tests specifically targeting the disposal field test proposed (see section 3.5)
are shown in Table 3-4 and will provide laboratory data under controlled conditions that
will be used to interpret the results obtained on coupons placed in the in situ heater
tests. The test matrix is focused on a broad range of materials and waste forms that
might be considered for a salt-based repository disposing thermally hot waste and will
provide a scientific basis to evaluate waste form strategies and material selection in
waste package design. The key test parameters are:
• Temperatures from 25°C to 300°C
• Humidity, low brine-inundated conditions
• Presence and absence of air/oxygen
• Brine composition
• Pressure, ambient to 20 MPa
• Ionizing radiation
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Table 3-4: Test Matrix for Alcove-Specific and Bounding Material Interaction Tests
Material
Environmental Conditions
Temperature
Humidity
Atmosphere
Ionizing
Radiation M
Actual In Situ
Heater Test
Container Materials
25°C - 300°C
Low,
moderate, and
high humidity
Air and Inert
at 1 and 20
MPa
0- 10,000 rad/h
Salt and Interbed
Material from the
Site
25°C -300°C
Low,
moderate, and
high humidity
Air and Inert
at 1 and 20
MPa
0 -10,000 rad/h
Possible Repository
Metals
25°C - 300°C
Dry, low,
moderate, high
humidity; brine
inundation
Air and Inert
at 1 and 20
MPa
0- 10,000 rad/h
These tests will build on past studies in salt (German HLW canister underground tests,
U.S. ONWI program, and WIPP) to provide a more robust understanding of material
performance in salt for the range of environmental conditions possible in a repository
where thermally hot waste is disposed.
The expectation in salt is that it is not necessary to design a container or waste form as
a barrier against radionuclide transport so it is not the intent in this proposal to give the
impression that these materials are required or that additional containment is necessary.
There are advantages to using certain materials, such as iron or stainless steel, for
maintaining a reducing environment which can provide defense in depth against
transport. The use of steam reforming, vitrification, or encapsulation in glass can reduce
solubility of the waste matrix but it is the contention, when burying in salt, that none of
these are required. The plan is testing the materials that make up defense HLW.
A wide range of analytical techniques are available to establish the reaction products
and overall reactivity. G-values (i.e., the number of molecules produced per 100 eV of
ionizing radiation absorbed) for gas generation in the salt irradiations will be established
by measuring gas composition and pressure as a function of time. Water content will be
determined as a function of the experimental conditions for materials that initially contain
water (e.g., salt, some waste forms). For the inundated tests, changes to the brine
chemistry will be determined to establish the appropriate range of brine chemistry for the
radionuclide source term studies.
The temperature range up to 300°C was chosen as a bounding value for the
temperature in the bulk salt formation. This temperature is used for the brine studies
and the material interaction studies. Temperatures near the canister heater could
exceed this value and the lab test may be modified through the test plan to reflect the
higher temperature. Local temperatures near the canister would be expected to
gradually decline by the time significant quantities of water could possibly contact the
canister and the waste.
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3.3.5. Measure the Effect of Elevated Temperature and Ionizing Radiation on Brine
Chemistry
High temperatures and levels of ionizing radiation present in thermally hot waste will
affect brine chemistry. Increased temperature will lead to changes in the solubility of the
major cations and anions present in brine, causing compositional changes in the brines
at the point of saturation, as well as shifts in the system redox potential (Eh) and acidity-
alkalinity (pH). These compositional changes could impact radionuclide solubility.
Radiolysis could lead to the buildup of oxidizing and/or reducing species that would
change the redox potential of the brine system. Gamma irradiation using self-contained
Cs source cells will be used in the laboratory to establish general radiolytic trends that tie
into the existing literature of established redox trends. The most important potential
impact of these radiolytic effects is on the redox distribution of radionuclides. The
proposed experiments to study and understand these effects are outlined in Table 3-5.
Table 3-5: Test Matrix for the Effects of Temperature and Radiation on Brine Chemistry
Brine
Environmental Conditions
Temperature
Ionic Strength
Atmosphere
Ionizing
Radiation
NaCI
25°C -150°C
0.1M-5M
anoxic
0-10,000 rad/h (y)
Variable isotope
(a)
MgCI2
25°C -150°C
0.1 M - 5 M
anoxic
0-10,000 rad/h (y)
Variable isotope
(a)
Simulated*
Brine A
25°C -150°C
Alone, Excess Salt, Waste
Package Materials
anoxic
0-10,000 rad/h (y)
Variable isotope
(a)
Simulated*
Brine B
25°C -150°C
Alone, Excess Salt, Waste
Package Materials
anoxic
0-10,000 rad/h (y)
Variable isotope
(a)
Simulated*
Brine C
25°C -150°C
Alone, Excess Salt, Waste
Package Materials
anoxic
0-10,000 rad/h (y)
Variable isotope
(a)
*Brines A and
brine compos
will be providt
C are "bracketing" simulated brine formulations that cover the range of expected
itions; Brine B is an intermediate formulation brine. Final detailed compositions
3d in the test plan for the laboratory work.
For all experiments proposed, changes in the brine chemistry (cation/anion composition,
Eh, pH) will be monitored as a function of temperature and irradiation condition. The
results of these experiments will bracket the potential changes in brine chemistry due to
temperature and radiolysis, as well as a measure of the extent that these changes are
overwhelmed by waste package constituents. Recovered precipitates will be analyzed
to establish their elemental and phase composition.
The thermal model performed for the generic salt repository (Carter et al. 2011)
produced peak bulk salt temperatures of approximately 150°C. This is the value that
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formed the basis for the temperature selection for the chemical studies since the higher
temperatures are localized near the canister.
3.3.6. Measure the Effect of Temperature on Radionuclide Solubility
The oxidation-specific solubility of key radionuclides will be established as a function of
temperature, using oxidation state-invariant analogs. This overall approach has been
used successfully in room temperature studies at WIPP and avoids the experimental
complexity of uncontrolled changes in oxidation state during the experiments. The
overall goal of this study is to establish the magnitude of the temperature effect on
radionuclide solubility to guide future performance assessment models. These data
would become important in any repository scenario in which water contacts the waste
and mobilizes radionuclides. It is likely that in any future repository program, these
scenarios will need to be investigated regardless of how robust the scientific evidence is
for encapsulation of the waste by the deforming salt medium.
The test matrix for the radionuclide solubility experiments is given in Table 3-6. Waste
package materials will be included in some experiments to account for sorption effects
and solid/liquid interface interactions.
Table 3-6: Test Matrix for the Effect of Temperature on Radionuclide Solubility in Brine
Radionuclide
Environmental Conditions
Temperature
Brine
Atmosphere
Waste Package
Materials
U(VI)
25°C - 150°C
Brine A, B, C
anoxic
Fe, Glass, TBD
Th(IV)
25°C - 150°C
Brine A. B. C
anoxic
Fe, Glass, TBD
Tc (IV)
25°C - 150°C
Brine A, B, C
anoxic
Fe, Glass, TBD
Cs
25°C - 150°C
Brine A, B, C
anoxic
Fe, Glass, TBD
3.3.7. Measure Radionuclide Oxidation Distribution and Redox Control at Elevated
Temperatures
Radionuclide speciation under the conditions possible in a high thermal load, salt-based
repository has not been studied extensively, and further research is needed. There is
currently very little empirical data on the speciation of many radionuclides for the range
of pH conditions likely to occur in these subsurface brines. For a salt-based repository
that will experience elevated temperatures, it is especially important to obtain data on
the effects of temperature on redox distribution and radionuclide speciation.
Some key actinides (uranium (U), neptunium (Np) and plutonium (Pu)) and fission
products (technetium (Tc)) can have multiple oxidation states in brine depending on the
redox potential of the brine system. The lower oxidation states of these key
radionuclides (U(IV), Np(IV), Pu(lll/IV) and Tc(lV)) should be less soluble. It is important
to measure the effects of elevated temperature on the processes that generally lead to
the creation of a reducing environment in an anoxic salt repository, which keeps these
radionuclides in lower oxidation states.
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The central objective of this subtask is to measure and quantify the effect of elevated
temperature on processes known to establish reducing conditions at room temperature.
The most important of these processes are pH/Eh variations, bioreduction, and reaction
with reduced metals (e.g., iron, manganese, others). The overall experimental approach
is to prepare the radionuclides in their higher-valent oxidation state, establish anoxic
conditions in a range of brine systems, and evaluate the effectiveness of reduction as a
function of temperature and self-irradiation effects (auto-radiolysis). The test matrix for
these experiments is given in Table 3-7.
Table 3-7: Test Matrix to Establish the Key Factors that Control Radionuclide Oxidation State
Process
Environmental Conditions
Temperature
Brine
Atmosphere
Components
Varying pH
25°C - 150°C
Brine A, B, C
anoxic
U and Tc will
be evaluated
Fe reduction
25°C - 150°C
Brine A, B, C
anoxic
U and Tc will
be evaluated
3.4. COUPLED PROCESS MODELING
Prediction of the thermomechanical and hydrologic response of the in situ experiment
will initially be made by benchmarking calculations using the best-available codes and
models. It is anticipated that at least the two major national laboratories will participate
in the benchmark calculations, and the international collaborators will be invited to model
the benchmark as well. Benchmarking computational capability is common practice in
repository programs, and was done on the WIPP program many years ago, on an
international parallel calculations exercise, and more recently by the European
Commission for calculations on the BAMBUS II experiment. The benchmark parameters
will be established by a technical team. The benchmark modeling cases will assume
that the initial modeling structure and the parameter values are understood and certain.
However, it is known that there are differences in the constitutive models adapted for the
state-of-the-art codes. The performance will be assessed in the benchmark exercise.
The benchmark model will be used to inform the field test personnel with regard to
placement of instrumentation and sample coupons, as well as establish the data quality
objectives for the main test parameters.
The benchmark models will be refined (validated/calibrated) using field test data to
match and predict the behavior of the actual system at the alcove scale. This work
proposes to benchmark and then refine calculational capability for design and analysis of
a salt repository. Because there is no current unified predictive model for
thermomechanical, hydrologic, and chemical behavior in bedded salt, the modeling will
be performed in two separate tasks, defined in the subsections below.
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3.4.1. Thermomechanical Benchmark Modeling
The overall objective of this modeling effort is to inform the field test design and to
assess the current capabilities of the thermomechanical computational codes available
to solve several complex initial/boundary value problems, which represent heaters,
excavations, and back-filled crushed salt of the in situ experiment.
This benchmark exercise will use codes that are appropriate for application to salt
repository calculations. Hopefully, several of the most developed constitutive models for
thermomechanical behavior of salt can be brought to the benchmark studies through our
proposed international collaborations. The advanced salt mechanics codes used by
research centers in Germany that are being considered for these analyses are
summarized in the Final Individual Report Joint Project: Comparison of Current
Constitutive Laws and Procedures Using 3-D Model Calculations for the Mechanical
Long-Term Behavior of Real Underground Rock Salt Mines (FZK 02C1587, 2010).
The calculations will be explicitly defined, such as a benchmark analyses of the Room H
test conducted at the WIPP horizon. Code-specific details (such as mesh refinement,
error bounds on iterative processes, and time step sizes) will be left to the modeler's
judgment. The type of output requested would include temperature distribution,
deformation at certain locations, and stress states. With the addition of the crushed salt
constitutive model and porosity-specific thermal conductivity relationship, these models
will be applied to specific numerical aspects of the field test.
Fully coupled thermomechanical modeling will provide information on temperature
distribution and room and drift closure. These calculations require constitutive laws for
deformation of intact salt, reconsolidation of granular, mine run salt, and thermal
conductivity of granular salt as a function of porosity. The state of the art to perform
these calculations will be assessed. Constitutive models will be enhanced by the
thermomechanical testing previously described. This management proposal
acknowledges that an essential part of the field test is to determine, at full scale, the
liberation processes and fate of the native brine. Therefore, a module for these
processes will be added to the coupled thermomechanical code. Considerations include
evolution and devolution of the disturbed rock zone, temperatures experienced in the
disturbed zone, permeability creation and healing, reduction in permeability of crushed
salt as density increases, and temperature distribution at a large enough scale to
ascertain if a condensation zone is possible. The fate of accessible brine is fundamental
to chemical considerations.
A preliminary assessment of the disposal concept has already been completed by
Sandia SIERRA Mechanics (Stone et al., 2010). These example calculations used the
SIERRA Mechanics code suite that is comprised of application codes that address
specific physics regimes. The two SIERRA Mechanics codes which are used in thermal-
mechanical coupling are Aria and Adagio (Stone et al., 2010). The suite of physics
currently supported by Aria includes the incompressible Navier-Stokes equations,
energy transport equation, species transport equations, as well as generalized scalar,
vector and tensor transport equations. A multiphase porous flow capability is a recent
addition to Aria. Aria also has some basic geochemistry functionality available through
embedded chemistry packages. The solid mechanics portion of the thermomechanical
coupling is handled by Adagio which solves for the quasistatic, large deformation, large
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strain behavior of nonlinear solids in three-dimensions. Adagio has some discriminating
technology that has been developed at Sandia involving the use of matrix-free iterative
solution algorithms that allow extremely large and highly nonlinear problems to be solved
efficiently. This technology also lends itself to effective and scalable implementation on
massively parallel computers. The actual thermal-mechanical coupling is done through a
flexible solution controller within SIERRA Mechanics called Arpeggio. Additional features
that need to be added include the temperature, stress, reconsolidation model for the hot
run-of-mine salt and a relationship between thermal conductivity and porosity, both of
which are elements of this proposal described earlier.
Fully coupled thermomechanical models involve three-dimensional details that will allow
prediction of the expected field test results. As improved modules for reconsolidation and
thermal conductivity are developed in the early stages of this proposed research, very
informative calculations can be executed. As noted in this management proposal, the
state-of-the-art codes and models, including SIERRA Mechanics, will be evaluated for
their ability to simulate the concept of disposal that will be demonstrated in the field test.
Preliminary examples of output are shown in the following Figures 3-2 and 3-3, which
are very similar to the results discussed by Stone et al. (2010). These preliminary
calculations show temperature distribution and run-of-mine salt consolidation that
simulates the alcove disposal configuration (thermally activated creep deformation
enhanced by an 8.4 kW canister). These calculations were run with a second canister of
hulls and hardware (approximately 10 meters from the back of the alcove) in addition to
the high-level waste canister located at the back of the alcove. Because the canister of
hulls and hardware produces no heat, it is not planned to be included in the SDI thermal
test.
Figure 3-2: Preliminary Temp Distribution for the Proof-of-Principle In Situ Field Test
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Figure 3-3: Preliminary Reconsolidation Calc for the Proof-of-Principle In Situ Field Test
As noted, the primary focus of the benchmark calculations is to inform the field test
design personnel with regard to expected full-scale in situ results. This information will
be useful for placement of gauges and density of coverage for certain measurements.
The benchmark calculations simultaneously allow ongoing assessment of the state of
the art for models and codes, while providing preliminary results that guide field testing.
To model the proof-of-principle field test as accurately as possible, the initial testing of
intact core at high temperature and the tests associated with reconsolidation need to be
completed and evaluated. The modeling process will involve continued refinement as
field and laboratory results are acquired, which will allow for improved modeling
capability. These results will be periodically reported in technical publications as the
project collects information. At the completion of the field test, a general model of the
thermomechanical behavior of the field test will be calibrated and published.
3.4.2. Hydrologic and Chemical Benchmark Modeling
Prediction of the thermal, hydrologic, and chemical conditions of the in situ experiment
will be made by benchmarking calculations using the best-available codes and models.
The overall objective of such a study would be to assess the current capabilities of the
thermal-hydrologic-chemical computational codes available to solve several complex
initial/boundary value problems, which represent idealizations of real drifts/rooms and
waste/backfill of the in situ experiment.
This benchmark exercise will use codes that have been developed for other thermal,
hydrologic, and chemical applications and apply them to salt repository calculations.
The calculations will be explicitly defined. Code-specific details (such as mesh
refinement, error bounds on iterative processes, and time step sizes) will be left to the
modeler's judgment. The type of output requested might also be much different from
that typically requested for drift design calculations and, in fact, the output data
requested will include specific numerical aspects of the field test application.
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This task will also seek to refine a modeling capability to predict the brine chemistry and
associated radionuclide solubility/concentration in high ionic strength brine systems at
the elevated temperatures expected in a high thermal load salt repository. The overall
modeling approach will extend the approach used at WIPP and will rely heavily on the
extensive experience gained from the WIPP and Yucca Mountain projects. The
empirical nature of this modeling approach makes it challenging to accurately predict the
effects of temperature without the availability of experimental results over the
temperature range of interest (25°C -150°C). Initially, simulation of the behavior of high
ionic strength solutions will be conducted using the best available databases and
information. An assessment will be made to determine if there are significant gaps in the
available data, and if so, the uncertainties will be parameterized and considered in the
subsequent modeling exercises. Then, as the project progresses, the prediction of
radionuclide solubility/concentration will rely heavily on the data collected in the
laboratory studies and temperature data from the in situ test. As a result of these efforts,
a modeling approach that accounts for higher temperature and a wide range of brine
composition will be configured. This model will provide needed concentration data to
define the radionuclide source term in subsequent transport and release calculations,
which may be required for future performance assessment calculations.
As noted, the primary focus of the benchmark calculations is to inform the field test
design personnel with regard to expected full-scale in situ results. The hydrochemical
calculation might be useful for placement of gauges and density of coverage for certain
hydrologic and chemical measurements. The benchmark calculations are exercises that
simultaneously allow ongoing assessment of the state of the art for models and codes,
while providing preliminary results that guide field testing. Also as noted, the modeling
process will involve continued refinement as field and laboratory results are acquired,
which will allow for improved modeling capability. These results will be reported in
technical publications as the project collects more and more information. At the
completion of the field test, a general model of the thermal, hydrologic, and chemical
conditions of the field test will be calibrated and published. Assuming that a fully
coupled THMC modeling capability is available during the project, this code would also
be employed for this purpose.
3.5. FIELD TEST PROOF OF PRINCIPLE
This section describes a preliminary, high-level plan to conduct a field test in salt to
evaluate its behavior under thermal loads representative of those that would be
experienced if HLW were disposed in salt. To set the stage for this proposed field test
program, first, the motivation and the basis for selecting the geometry and conditions of
the test is described. One of the most important elements affecting the design of a HLW
repository is heat management. A disposal safety case, properly conceived and
elucidated, relies on well-understood processes attesting to the stability and durability of
the geologic barriers to radionuclide migration over geologic time scales. Perturbations
caused by the installation of a mined opening or the emplacement of waste must be
carefully considered. As such, the decay heat from the waste places limits on the
maximum possible areal density of waste, with a significant impact on utilization
efficiency of the subsurface facility. Consequently, the management of waste before it is
emplaced in the repository, and the configuration of waste packages underground, must
be conducted such that critical thermal design criteria are met.
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Another requirement affected by heat is that of predictability: models used for repository
design and performance assessment calculations must be demonstrated to be valid for
their intended purpose, to provide assurance that the repository will perform as expected
during operations and in the post-closure period. During operation, the stability of the
mined facility and the temperatures and radiation environments to which workers will be
exposed must be well understood and operations conducted so as to minimize risk to
workers and the public. During operations and after permanent closure, parameters such
as the maximum allowable temperatures experienced by the waste form, engineered
waste package, and the surrounding medium must be established to ensure that the
isolation capability of the repository system is not degraded as a result of decay heat.
Because heat is a disturbance from the natural state of the geologic medium, a
comprehensive understanding of those changes must be demonstrated, and those
changes reflected in validated models of the physical/chemical system, in order to
support the safety case for geologic disposal. If it can be shown that salt behaves in a
predictable way (as demonstrated by a validated numerical model) and that the waste
isolation capability of the salt host medium is not degraded relative to isothermal
disposal conditions, then important strides will have been made in expanding the safety
case for salt to include disposal of thermally hot wastes.
3.5.1. Preliminary Work: Conceptual Disposal Concepts
To conduct meaningful, focused research in geologic disposal, an appropriate starting
point is a disposal concept describing the physical configuration of wastes in the
underground, and the operations that would be conducted to load the repository. For
salt, the favored approach is to select a disposal concept that is reasonably bounding in
terms of local and areal-average heat load, is feasible and efficient operationally, and is
likely to result in a solid safety case provided that issues identified as uncertainties are
addressed. A study of a generic salt repository for disposal of thermally hot HLW (Carter
et a I., 2011) documents the basis for the disposal concept adopted in the present study.
That study, which proposed a conceptual design of a repository from a future closed fuel
cycle producing large quantities of heat-generating borosilicate glass HLW, presented a
subsurface and surface facility design and disposal strategy that, in principle, can be
practically realized using proven mining operations. The study assumed that waste with
significant radionuclide mass loadings, including Cs, Sr, and other heat-generating
elements, would be buried with minimal decay storage, thereby providing an aggressive,
bounding case with respect to the thermal load.
The design concept is based on a disposal strategy in which a series of repository
panels, each of which is a subsurface cell consisting of individual rooms and a total of
236 alcoves, are constructed underground (see Figure 3-4 for the configuration of a
single panel). The disposal operation, detailed in the insets in the figure, would consist of
placement of one HLW canister at the end of each alcove. Mining operations would be
performed on a "just-in-time" schedule such that the waste would be emplaced soon
after the mining of a particular area is completed. Carter et al. (2011) determined that,
for the assumed repository layout, operating conditions, and waste streams, that HLW
from a facility reprocessing 83,000 Metric Tons Heavy Metal of UNF, operating for a
period of 40 years, could be disposed of in a repository of 96 panels covering an area of
2.1 by 2.5 miles, or 3,350 acres. In addition, because the layout and linear distances of
mined repository are controlled by the need to spread HLW out to distribute the heat
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load, ample space would also be available to co-dispose of other radioactive waste
streams such as GTCC and LLW that would be generated in a reprocessing plant. The
HLW package and potentially remote-handled (RH) waste being co-disposed in the
same alcove would be covered by crushed salt backfill to provide radiation shielding for
workers conducting operations in the vicinity. This strategy is intended to enable a
simpler disposal operation than the emplacement methods into the intact salt than those
in which boreholes are drilled into the intact salt, making it easier for the disposal
operation to "stay ahead of the heat from previously disposed waste.
Figure 3-4: Disposal Concept of Carter et al. (2011) Used as the Basis of the Proposed
Field Testing Program
1
» »» «
r
I * -
r
i
*>* i
,
-------
Figure 3-5: Alcove-Scale Thermal Simulation: 100°F Isotherm as a Function of Time.
(Plots are for a horizontal slice through the waste package, parallel to the alcove floor.)
Time (day) IQ
1!
Time (day) !tM)
Note: figure reproduced from Clayton and Gable (2009)
Figure 3-6: Repository-Scale Thermal Simulation.
(Temperatures above 100°C are represented by the extreme color in the color bar.)
10 Years
100 Years
200 Years
1000 Years
Note: figure reproduced from Clayton and Gable (2009)
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However, details at the alcove scale, including processes for which there is insufficient
knowledge, have a strong bearing on the local conditions experienced by the waste and
surrounding salt. For example, one hypothesis pertinent to this disposal concept is that
the crushed salt will rapidly reconsolidate when compressed due to alcove closure, and
that this process will be accelerated due to heat, relative to room-temperature salt creep
processes. However, Figure 3-7, reproduced from Clayton and Gable (2009), shows that
if the crushed salt reconsolidates either gradually (Sensitivity Case 2) or not at all
(Sensitivity Case 1) within the first 50 years after disposal, the average temperatures
experienced by the waste would be much higher than if the crushed salt rapidly
consolidates and attains the thermal properties of intact salt (the Base Case).
Unconsolidated crushed salt has a very low thermal conductivity compared to intact salt,
leading to an insulating effect on the waste package and contents until the crushed salt
consolidates. Thus, the mechanisms and timing of the crushed salt consolidation
process must be understood and incorporated in a model that can be used to iteratively
develop a robust repository disposal concept.
Figure 3-7: Average Waste Temperatures Versus Time for Different Assumed Behaviors of
the Crushed Salt Backfill
Time (years)
Note: figure reproduced from Clayton and Gable (2009)
Note that slow reconsolidation of the crushed salt would not be a "showstopper" issue: a
disposal concept that would mitigate the impacts of insulation of the waste package
could be devised that would keep waste temperatures lower, all other things equal.
Clayton and Gable (2009) discussed several viable solutions, including: aging the waste;
disposing of waste with lower loadings in a greater number of alcoves; or designing the
shape of the waste form to facilitate heat transport away from the canister. Nevertheless,
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answering this scientific question would enable a robust disposal concept design to be
devised that supplies a high degree of assurance that the waste would remain within
specified limits of temperature.
3.5.2. Conceptual Field Test Design
The alcove waste-disposal concept of Carter et al. (2011) described in the previous
section innovatively balances safety, ease of operation, and heat management. This
configuration is different than the configurations tested at Lyons, Kansas; Avery Island,
Louisiana; or the thermal/structural interaction tests at WIPP, In these earlier tests, live
nuclear waste packages (at Lyons) and electrical heaters (at WIPP, Lyons, and Avery
Island) were placed in vertical boreholes drilled into the floor of the mine. The proposed
field test consists of seven alcoves with five of the alcoves containing an electrical heater
to simulate a disposed waste package. Each electrical heater will be placed on the floor
near the back of the alcove and covered with crushed salt. Thus, the waste-disposal
configuration for the field test is a full-scale mock-up, with heat loads and spacings that
are intended to bound thermal conditions for disposal operations. The field test,
laboratory tests, and modeling activities will produce data directly applicable to a
potential repository, reduce the uncertainty of current predictive models, and allow
improvement to the scientific bases of the models.
The test will incorporate measurements of temperature changes imposed on the intact
salt surrounding the alcove (roof, floor, and pillars) and mine-run salt placed as backfill
over the waste. Closure and entombment processes will be measured directly by
various deformation gauges, as well as post facto forensic reconnaissance. Hydrologic
effects will be determined through the monitoring of moisture/brine movement in and
around the test alcoves, as well as down-drift in the exhaust air. In addition, chemical
effects on various metal coupons and radionuclide analog elements will be assessed
during the forensics stage. The test bed is expected to see temperatures in excess of
160°C in the salt mass (see section 3.4.1). The alcove tests will be complemented by
laboratory tests on dry mine-run salt to determine its deformation characteristics at
elevated temperatures (200-300°C) and on intact salt specimens to obtain creep rates
above 200°C. The pre-test and post-test chemistry and environmental parameters will
also be evaluated and compared to laboratory test results under more carefully
controlled environmental conditions. The underground experiment measures the
imposed transient temperature field, the accelerated deformation in the intact salt and
backfill, and the movement of moisture/brines in the salt. Figures 3-8 and 3-9 illustrate
in a perspective view, the general layout and architecture of the field test and a typical
heated alcove. Note that Figure 3-8 only shows the thermal test area and adjacent
access drifts. It does not show the cross cuts and outer most ventilation and access
drifts that are shown on Figure 3-10.
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Figure 3-8; Perspective View of the Mining Layout for the SDI In Situ Thermal Test
Figure 3-9: Areal View of a Typical SDI Alcove
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Figure 3-10 illustrates the approximate area within the WIPP that would most logically
support the field test. Some of the major considerations to the exact placement of the
test within the WIPP are: 1) this test will not interfere with WIPP operations, 2) the test
should be located to the north, as far from waste handling operations as possible, and
outside the shaft pillar area, 3) the test should not interfere with existing scientific testing
occurring in the northern part of the facility, and 4} the test should exhaust directly to the
exhaust shaft.
A concept that would address each of these criteria sites the test bed a few hundred feet
south of the N-110G drift in the WIPP facility and outside the shaft pillar area.
Approximately 9,500 linear feet of mining would be required to implement this concept.
A two-drift access drift, one originating from N-780 and the other from N-t 100, with cross
cuts would provide ample ingress/egress as well as sufficient controlled ventilation for
accelerated forced cool-down of the test bed. The ventilation return would be directly to
the exhaust shaft. This arrangement allows for accelerated cooling for access to the test
bed to conduct post-test forensics. Additionally, it allows for rapid cooling of the test
area if required.
The test will be located in a representative selection of salt, characterized during the
early mining stages prior to turn out for the test bed. The test bed would be located
approximately mid-way between WIPP Marker Beds 138 and 139 in the facility. Specific
details related to test bed criteria and placement will be documented and transmitted to
the construction support organization by way of the F&OR document and detailed field
test plan.
Figures 3-11 and 3-12 illustrate the general layout of the waste-alcove type salt
repository to be demonstrated in the field test. The primary objective of this full-scale
demonstration is to provide thermal, structural performance, and hydrological data for
the alcove configuration. In detail, the objectives of the in situ heater test are to:
¦ Measure temperatures to confirm heat transfer calculations.
» Monitor salt movement (alcove deformation) to validate salt creep calculations.
• Impose reconsolidation on the crushed salt to test the salt-reconsolidation model.
• Determine brine and vapor movement for initial information on moisture effects.
• Validate far-field thermal modeling capability by having several interacting alcoves.
• Provide a specific problem and detailed in situ test data for three-dimensional
computer code validation and benchmarking.
• Evaluate chemical effects on coupons of various materials placed in proximity to
canisters and associated changes in the in-field chemistry and environment.
Details of the in situ heater test will be developed in a formal field test plan based on the
F&OR document. After the test plan is written, CBFO will review and provide final
acceptance of the test plan. The concepts displayed here are sufficient to allow
reasonable estimates for cost and schedule.
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Figure 3-10: Proposed Area within WIPP for the SDl Heater Test
TEST AREA
Access Drifts: 0,033 fset @ 10 wide by 13' high, 137,826 tons
Host Test Area: 7061 torn
Alcoves: 7 H 220 tons Mch, 1 £40 tons
Total Mined Tons: 146,52®
swT mum «»
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Figure 3-11: Plan View of the Mining Layout for the SDi In Situ Test
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Figure 3-12: Plan and Profile View of a Typical Alcove
21
NOTE: Dimensions are in feet. Dimensions are preliminary, not to scale, and for planning
purposes only. Angle of repose of the salt is for illustration. Exact layout and dimensions will be
documented in the F&OR document and the detailed field test planning documentation. Cylinder
shown at the back of the alcove is the canister heater simulating the thermally hot waste canister
and will be placed in a notch at the back of the alcove for stability and enhanced heat transfer.
Seven alcoves will be instrumented to measure brine and vapor movement,
temperatures, deformation, closure in and around the alcoves, pressure in the crushed
salt, and ventilation conditions. Because of the large deformations and brine conditions
expected during the test, redundant instrumentation from observation drifts as well as
from within the test alcoves themselves will be deployed. Robust signal wiring, including
wireless signal transmission, will be investigated and deployed if suitable. Geophysical
techniques as described in section 3.5.3 will be used to assess test conditions. Remote
visual monitoring through high temperature camera systems will also be deployed. The
proposal team intends to include our international peers in review of this test
arrangement.
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The field test will use electrical heaters to simulate the waste packages. The concept at
this stage includes 8.5 kW heaters that should bound the thermal output of any waste
placed in each alcove. This thermal loading pushes the a real heat density to
approximately 40 W/m2, which will produce temperatures well above 100°C,
(temperatures above where most data have been acquired to date) in the nearby
undisturbed salt. The heaters will have sealed (welded) ends with high-temperature
potted electrical leads. The electrical controller will use a step-down transformer to
regulate heater power. These values will be validated and specific heater wattages and
areal heat loading values will be specified in the field test plan.
Electrical Heater Stability During Testing
The concept of buoyancy includes the notion that the waste will either "melt" its way
downward or float upward, and the heated volume of salt may move upward as a result
of its reduced density. The planned field test instrumentation includes surface surveys
that are part of the performance confirmation monitoring program for WIPP. Thus, any
uplift will be measured from these very accurate surveys. Measurement of buoyancy in
situ will be investigated if practical geophysical and instrumentation techniques can be
identified.
The movement of canisters containing heat-generating nuclear wastes buried in a salt
formation has been hypothesized. The existence of buoyant forces due to thermally
produced density differences suggests the possibility of initiating convection cells in a
plastic medium like salt. A proper assessment of this motion includes considerations of
the temperature dependence of the effective viscosity and thermal conductivity of the
salt, as well as the decreasing thermal output of the heat-generating wastes with time.
Analyses performed in the 1970s indicate that very little canister movement will result
during the heat-producing life of the waste canisters. The transient analyses show that
initially the canister will sink. Then, due to the formation of a convective cell in the salt
from heating by the wastes, the canister will rise. Eventually, as the convective cell
diminishes, the canister begins to sink again. Predicted displacements are less than a
canister length during this process. The steady-state analyses provide upper bounds on
the magnitudes of upward velocity possible during heating. In all cases, the velocities
are sufficiently small to indicate that very little movement will occur while the canister is
capable of producing heat.
Field Cost Estimates
Cost estimates are developed on a "per alcove" basis, using the fully instrumented
alcove. There will be modifications to the instrumentation arrangements, particularly in
the two alcoves without heaters. And the final design will almost certainly add to and
otherwise change some of the detail exhibited here. The precise instrumentation
configuration will be developed in a detailed field test plan. Nonetheless, the array of
instruments provides a reasonable overview of the in situ test for estimating purposes.
Table 3-8 provides a breakdown of the measurement types, measuring devices, and
estimated quantities, along with cost estimates for the in situ heater test. Table 3-9
represents the additional total equipment purchase costs for the in situ heater test.
Some select instrumentation and equipment will be developed and/or purchased in FY12
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and FY13. The data acquisition system, the heaters and controllers, and the remainder
of the equipment will be purchased in FY14 in preparation for a heater start in mid FY15.
Table 3-8: Instrument Costs per Alcove for the In Situ Thermal Test
Measurement
Sensor Type
Estimated
Number
per Alcove
Estimated
Installed Cost
($K)
Roof-Floor Closure
One-meter range, spring loaded
pull-wire potentiometer, temperature
compensated
4
$30
Salt Displacement
and Deformation
Multiple Point Borehole
Extensometer (MPBX) with invar
rods and four displacement
transducers
5
$90
Temperature
Thermocouples/RTDs
40
S70
Crushed-Salt
(Backfill) Pressure
on Heaters
Temperature-compensated load
cells between buried loading plates
4
$30
Heat Flux to Salt
Flexible high conductivity heat-flux
meter mats with precisely positioned
thermocouples
4
$30
Water Vapor
Movement
Systems for monitoring of vapor
movement within the test bed {e.g.,
air volume, temperature, humidity,
sonic velocity, electrical-resistivity)
1
$40
Estimated Instrument Cost per Alcove
$290
Estimated Total Instrument Cost for 7 Alcoves
$2,030
Table 3-9: Equipment Costs for the In Situ Thermal Test
Equipment &
Hardware
Description
Quantity
Estimated
Installed Cost
(SK)
Heaters with
Controller
Rod heaters (redundant leads and
elements), 10kW capacity in 24-inch
diameter casing, sealed both ends,
potted high-temp leads
5
$750
Data Acquisition
Multi-channel DCS
1
$350
Fiber optic
communication
system
Communications cable data hub and
system to communicate data to the
DCS and the surface
1
$250
Cameras &
Recording
10 digital video cameras and video
station
1
$200
Estimated Total Equipment Cost
$ 1,550
A 24-month heating interval is anticipated, followed by an 18- to 24-month cool-down
period. Information to be gathered after the heating period includes sampling the
reconsolidated crushed salt for forensic studies, including optical and scanning election
Salt Disposal Investigations 52
June 2011
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microscopy and limited physical arid mechanical testing. The heaters and any attached
metal coupons will be recovered and evaluated,
A team responsible for experimental operations consisting of a test coordinator and field
testing support staff will be required to perform equipment testing, shakedown, technical
operation, monitoring, maintenance, data collection, data reduction, operational
assurance, and reporting. Additionally, the Principal Investigators and field test scientific
management is required for the duration of the test once it begins heating in FY15.
3.5.3. Mining and Construction Support
The proposed in situ testing effort requires salt mine access. To aid in determining
relative costs, a division of responsibilities has been developed for this proposal and as
shown in Table 3-10, which delineates the anticipated work breakdown.
Table 3-10: Partitioning of Responsibilities - Construction & Operations Support and Testing
Activity
Pre-Test
Planning
Const, and
Ops Support
Testing
Prepare mine layout and specifications
X
Define infrastructure needs (air, electrical, comm)
X
Develop detailed field test plan
X
Excavate the defined openings (access and alcoves)
X
Install ventilation structures
X
Drill/core instrumentation boreholes
X
Install instruments in boreholes (e.g., MPBXs,
thermocouples)
X
Install data collection system (DCS)
X
Connect instruments to DCS
X
Run fiber-optic cable from DCS to surface
X
Connect fiber optics to transmitter
X
X
Install electric power distribution
X
Install electric control panels and heater controllers
X
Install heaters
X
Provide underground compressed air
X
Routine supply delivery (aboveground to test area)
X
Special equipment delivery
X
Facility management and science program interface
X
Test coordination, oversight and facility interface
X
Install ventilation monitors
X
Install instrumentation
X
Install heaters in alcove
X
Cover heaters with mine-run salt
X
Install instruments in mine-run salt
X
X
Daily heater power inspection/regulation
X
Instrumentation and DCS maintenance
X
Collect and analyze test data
X
End of test forensics, recovery & decommissioning
X
X
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The estimates for mining and infrastructure are estimated from direct mining experience
at WIPP. The operating WIPP facility provides advantages in terms of operating
infrastructure, Mine Safety and Health Administration (MSHA) qualification, equipment,
and resources. The field experiment will not interfere with the WIPP operations or the
greater WIPP mission.
It is estimated that the savings for mining and infrastructure costs exceed 50% of those
in the original proposal from February 2010. The infrastructure at WIPP, as well as
mining equipment and machinery, has already been purchased by the DOE. WIPP
personnel and equipment would facilitate mining, mucking and trucking, utilities,
transport, surveying, craft support, facility operation, and safety. Estimates are shown in
Table 3-11. The labor and infrastructure associated with mining and engineering at the
WIPP are existing WIPP resources and will not require new SDI budget. However,
those total costs are accounted for, but not included in the new SDI specific budget
necessary to complete the work. Consumables and equipment (e.g., ventilation control,
power distribution, the purchase of a new core rig) are included as direct costs requiring
new SDI budget. The cost estimate also includes forensic back-mining in the last year of
the project to retrieve coupons, salt samples, and the heaters for laboratory analysis and
determination of in situ alcove environmental conditions, mineralogy, and brine
chemistry. As before, the total costs are shown, but not included in the roll-up of
necessary new SDI budget to conduct the work. As there are no mining or infrastructure
costs in FY11, the following table begins in FY 12.
Table 3-11: Mining and Infrastructure Costs (in thousands of dollars)
Activity
FY12
FY13
FY14-FY18
FY19
FY20
Mining, Surveying, Salt Disposal, and
Management (existing WIPP
resources)
($1,500)
($1,500)
Core Rig Purchase & Coring i
$1,700
Ventilation Control
$250
$250
$50
Power Distribution
$200
$200
$600
Safety Case & Work Control
$50
$50
$50
Ops Support
$3,000
$700
$500
Test Forensics, Mine Back
($1,500)
Total SDI Budget (new) per year
$500
$500
$5,400
$700
$600
Total Cost (incl. existing resources)
$2,000
$2,000
$5,400
$700
$2,000
The total distance mined for test access rooms and alcoves for the basis of estimate is
approximately 750 linear feet at approximately 11 feet wide by 10 feet high.
Approximately 9600 total linear feet of mining (approximately 16 feet wide by 13 feet
high) will be required in the north section of the WIPP in order to gain access and
properly ventilate the test area. Each alcove will be backfilled with run-of-mine salt after
the heater is placed in the alcove as shown in Figure 3-9. Whereas the detailed field
test plan will have exact layouts and dimensions, it can be expected that there will be
approximately 20 boreholes per alcove (cored from both inside and outside the alcove).
If each borehole were an average of 20 feet long, an approximate total of 4,000 linear
feet of precisely placed boreholes will be required to field this test.
Salt Disposal Investigations
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The five heaters at 8.5 kW will require a power load of 43 kW. Assuming a 25% load
factor, this would be 53 kW of power. The instrumentation, equipment, lighting, and
general power will require 10 kW clean 110V/220V single-phase power,
3.5.4, Geophysical Assessment and Monitoring of the Field Test
A key test parameter associated with this experimental work is brine and vapor
movement in the salt formation during heating and cool-down. These measurements are
generally not as straightforward to make as is monitoring for temperature or ground
movement. Additionally, the large ground movements and brine conditions expected to
be seen during the test will make it imperative that measurement techniques not
dependent upon hard wired gauges down a borehole be used where feasible. As such,
new or more advanced techniques are likely to be developed and employed in this field
test to measure, at a minimum, vapor and brine movement. These techniques are also
anticipated to provide three-dimensional information regarding mechanical changes and
physical closing of alcove openings to complement more direct measurement methods.
Geophysical techniques (in addition to the more traditional instrumentation listed in
Table 3-8) are expected to be developed, demonstrated, and potentially deployed to
monitor salt alcove properties important to the test. These categories of salt alcove
properties, features, and behavior may include; 1) fluid migration, 2) alcove interface
rheology and structural changes, 3) thermally induced seismicity, and 4) electrical
properties. A two-year duration period at the beginning of the time-line is set aside to
develop and demonstrate these techniques such that measurement techniques sufficient
to monitor salt alcove properties important to the test, in particular for vapor movement,
are achieved. All of these methods are proven but are site- and application-specific.
They are low risk in that they are well established, but some may not be appropriate for
this problem due to such issues as minimum spatial resolution and limited sensitivity to
contrasts between solid, fluid and vapor phases. For these reasons, higher risk is
associated with applying these techniques to fluid and vapor migration. The
demonstration period will be used to develop advancements that address the resolution
and sensitivity issues. The following section discusses some of these techniques,
Near real-time (four-dimensional (4D)) interrogation (using repeated active and passive
seismic and active resistivity measurements) may be made at sufficiently large standoff
distances to avoid the potential damage to the sensor networks that could occur due to
high temperatures and major structural changes in and immediately surrounding the test
alcoves. Two primary thermally induced physical processes associated with the salt
heater test may be monitored: 1) thermomechanical evolution and deformation of the
alcoves, backfill, and surrounding formation, and 2) migration of fluids (brine) within and
between these same structural components. As with the more detailed description of the
thermomechanical instrumentation, the geophysical monitoring layout would be
integrated with the field test plan and reviewed by internal technical teams. Stand-off in
situ seismic and electrical resistivity experiments are proposed for the salt heater tests to
quantify: 1) the thermomechanical evolution of targeted structural components, and 2)
the migration of brine within these same structures. The work would also build on and
provide support for the point measurements of salt alcove deformation (extensometer)
and temperature (thermocouple) outlined in earlier sections by providing full 3D time-
lapse measurements of the entire volume surrounding and including the alcove, backfill,
and heaters. Furthermore, the seismic and resistivity arrays would survive major alcove
Salt Disposal Investigations
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deformation or collapse that might damage the exten so meter and thermocouples. The
following geophysical techniques are proposed.
• Active time-lapse in situ seismic wave transmission measurements and
monitoring. Active seismic methods are the primary tool that could remotely,
noninvasively detect subtle thermal/mechanical changes within the test area.
Reflection imaging and transmission imaging could provide complementary
information of the test area.
The velocity at which seismic waves travel through solid material varies with density,
temperature, and pressure. The density, wave scattering properties, and energy
dissipation of the material also change with temperature. Thus, spatial variations in
the travel time, scattering, and attenuation of seismic waves can be used to map
changes in seismic wave velocities, material density, heterogeneity, and viscoelastic
properties caused by temperature gradients in and around a heated region of salt
and/or brine and vapor movement. One method that may be used is known as
seismic tomography and is similar to techniques used in medical X-ray diagnostics.
Full 3D coverage of the region surrounding heated alcoves with appropriate
seismometers or accelerometers would allow detailed 4D tomograms to be obtained
using active seismic data acquired at different times, which would illustrate how the
spatial temperature profile around the heaters evolves. 3D ray tomography and 3D
double-difference waveform tomography are proposed to obtain high-resolution 3D
images showing where temperature changes occur. When the source frequency is in
kilohertz, the anticipated spatial resolution of 3D images would range from
approximately 0.5 m to a few meters (or half wavelength to 2-3 wavelengths),
depending on tomography algorithms. It might be possible to attain .25 m resolution
or better with higher frequency sources, since the experimental layout is very
compact (Schuster, 1996).
• Passive seismic event monitoring. The deformation induced by heating the salt
will likely result in multiple scales and degrees of brittle failure of the alcove structure
and surrounding formation. During initial heating, small-scale deformation might
occur along cracks or fracture planes, either by crack growth or by slippage along
pre-existing planes of weakness. These discrete events will result in very small
microseismic or acoustic emissions. As heating progresses, large-scale fracturing
can occur in the salt alcove walls, ceiling, and floor. Data from these events can be
used to determine the location, development, and extent of the fractures, as well as
the fracture mechanism itself. Performing the passive seismic monitoring will not
require additional instrumentation; both passive and active types of thermally
induced seismicity can be detected using the same seismometers or accelerometers
that would be deployed for the active seismic experiments discussed above. Event
location resolution is expected to be about 0.3 m, based on previous work. Further,
with sufficient 3D coverage of receivers surrounding the microseismic sources, it
would be possible to resolve the type of crack deformation being induced, for
example, tensile vs. shear deformation. The microseismic data would provide an
important measure of how thermal-induced strains are accommodated discretely in
the salt body and how they lead to major structural events. A passive seismic
monitoring system will provide insight into the presence and source of brittle
phenomena. One might expect flexural tensile brittle processes and possible
acoustic emission from proximal anhydrite, because of its stiff rheologic response.
Salt Disposal Investigations
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Therefore, a carefully arrayed seismic network will be evaluated for deployment iri
the field experiment.
• Active time-lapse seismic reflection imaging and monitoring of alcove
interfaces. Seismic/elastic reflection imaging (migration) techniques produce much
higher resolution 3D images of subsurface material interfaces than transmission
tomography, from which such interfaces are often invisible. Seismic reflectors are
structural interfaces separating two materials with different seismic impedances. The
primary interfaces of interest in this study are those between the solid salt alcove
walls and the crushed salt backfill, plus the interface between the heater and its
surroundings. Seismic reflection signals would be used to produce high-resolution
3D images of interfaces in the vicinity of the heater test (Fehler and Huang, 2002,
Annu. Rev. Earth Planet. Sci., 30:259-284.).
• Electrical resistivity measurements. Measurement of electrical resistivity is a
powerful technique for probing and monitoring geological systems, including rock
and salt formations, because the technique is very sensitive to small changes in
electrical properties. Repeated in situ measurements of salt resistivity would provide
high resolution 3D time-lapse images of temporal changes related to fluid migration.
A combination of field and laboratory measurements is proposed to apply electrical
techniques to characterizing the moisture movement within the salt. In situ field
measurements would be performed to obtain baseline measurements and to
characterize electrical resistivity as the salt body warms. Several techniques would
be used for imaging electrical resistivity, including electrical profiling (surveying) and
transient electromagnetics (EM). Data from individual 2D electrical surveys and
electromagnetic soundings can be combined into 3D data cubes. Because resistivity
values of salt range from 10 to 1013 ohm-m under ambient conditions, the influence
on resistivity of grain size, hydration, temperature, and possible clay content must be
determined via laboratory measurements in order to interpret the field data. These
measurements would allow for better interpretation of the range of resistivity values
that would be observed, as well as for better discrimination among thermal
compaction, water content and migration, and clay content. Although electrical
resistivity methods are typically less well know by geophysicists, there is a large
amount of experience, and many companies which specialize in electrical techniques
(e.g., Zonge, www.zonge.com; geometries, www.geometrics.com; sensors&software,
sensoft.ca; fugro airborne services, www.fugroairbome.com, hydrogeophysics,
www.hydrogeophysics.com; and Willowstick, www.willowstick.com).
• Joint Seismic and EM imaging. Electrical and electromagnetic signals are more
sensitive to brine and vapor movement than seismic measurements. On the other
hand, the resolution of seismic imaging is much higher than EM imaging. Joint
seismic and EM imaging could significantly enhance detection of brine and vapor
movement. Joint seismic and EM imaging is proposed for monitoring brine and vapor
movement in the salt formation during heating and cool-down processes.
3.5.5. Feasibility of Reentry into the North WIPP Experimental Area
Excavation for siting the SDI field test could potentially allow reentry to the north
experimental area, which was abandoned over twenty years ago. The feasibility of this
idea will be developed as the SDI work continues and is not currently planned,
Salt Disposal Investigations
June 2C11
57
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budgeted, or scheduled. The concept is put forward here because the proposal team
recognizes a possible opportunity for forensic reconnaissance of previously heated
rooms.
As illustrated in Figure 3-13, heated room experiments were conducted in A and B
rooms in the north experimental area. The A room tests were heated at an equivalent of
18 W/m2 mockup. The B room was called the defense high-level waste (DHLW)
overtest. These tests were abruptly terminated, and at least some heaters were
abandoned in place. At least one heater was overcored and removed, but no
examination was made of the reconsolidated salt attached to the heater, the nature of
brine migration in the intact salt adjacent to the heater, or of possible corrosion on the
heater itself. Other abandoned heaters and the proximal salt may be accessible for
examination after more than 20 years in situ. The opportunity and practicality of reentry
will be investigated.
Figure 3-13: Location of Past Field Tests Located Within WIPP
FIELD TESTS:
1378 m
TRU TEST PANEL
(SPDVS
EXPERIMENTAL AREA
i i t a
EXPERIMENTAL
AREA
¦pp
I IIS
T
A. 18 W/m3 MOCKUP
DHLW OVERTEST
.. INTERMEDIATE SCALE ROCK MECHANICS
AND PERMEABILITY TESTS
MINING DEVELOPMENT
Cr, GeOMeCHANICAL evaluation
Vl heated pillar
J. SIMULATE® CH TRU TESTS (WET) AND
MATERIALS INTERFACE INTERACTION TEST (MIIT)
L PLUGGING AND SEALING,
WASTE DRUM/BACKFILL TESTS
i\C SMALL SCALE SEAL PERFORMANCE TESTS
SIMULATED CH AND RH TESTS
CIRCULAR BRINE ROOM TESTS
AIR INTAKE SHAFT PERFORMANCE TESTS
AIR
INTAKE
SHAFT
r' n
c
J
K*
WASTE
HANDLING
SHAFT
u
An
/
SALT HANDLING
SHAFT
'U/
«nfh
iUlD
EXHAUST
SHAFT
\
Note: Only north portion of WIPP facility shown.
Salt Disposal Investigations
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4. COST AND SCHEDULE
4.1. COST AND SCHEDULE
Table 4-1 lists the cost (in thousands of dollars) by element for each portion of the
proposal by fiscal year. The budget estimates are constrained for the first two fiscal
years. Table 4-2 shows a breakdown of the activities by funding organization, both
DOE-EM or DOE-NE.
Figure 4-1 shows the expected duration for the test by element under the funding profile.
Figure 4-2 shows an accelerated schedule with a heater test start in FY14 if additional
funding were provided in the first two years of the test.
The Yucca Mountain Drift Scale Test took approximately 2.5 years (mid 1995 to Dec
1997) to construct and install at a cost of approximately $19 million (including mining,
drilling, and engineering costs). The SDI thermal test is estimated to take approximately
3.5 years (Oct 2012 to mid 2015) at approximately $28 million (plus the in-kind costs of
construction, drilling, and engineering work). Therefore, based on past experience and
comparison with other large underground thermal tests, these cost and schedule
estimates are reasonable.
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Table 4-1: Cost by Element (in thousands of dollars} - Budget Constraint on the First Two Fiscal Years
| S»ct* |
COSTS (»it)m»t«d) BY FISCAL YEAR ($1,000K)
FY16 | FY17 | FY IS | FV19 | FY20 | TOTALsl
SDI Propoul
Tnk/Produrt
Comments
FY11
FY12
FY13
FY14
FY 15
| Management, Quality Aisurawc, and Safety | 2.1-2.3
Management, quality Assurance, and Safety
wso
SUMO
$900
$900
$600
$600
$600
$600
$700
$«00
$6,95o|
PrQj Mgmt, OA Support, Performance and Safety Analysis/Approvals
* Includes F&OR document development m FY11 (Section 31)
s*»
Sax
$900
SMO
S«W
$600
SMC
$600
$600
ssoo
$6,650
5-100
Detailed Test Plan Development
" Development of detailed test p ion in FY13
$400
| Int et nal tonal Colbbor«t ion
2.4
|lntetiu(k>n>l CoRtborttion
sof
$2001
$20o|
sjooI
SJ50
$2$ol
$25ol
$2001
$200!
S200[
$l,95ol
] Lab Thermal a nd Mechar\lol Studies
S3 | Bound Sitt Thermomechankal Response
|*r«t «on development ono tarty lab tilting In FY! 1
tt»l
wool wool
$300
$300
$300
$300
$300
$400
$soo|
$3r45o|
| laboratory ttydr^tojk, Chemkal, and Material studiei
3.3 laboratory Tests in Support of Modeling, PA. and the Field Test
s°r
mmmw*
$$00
$500
$soo|
$300
$300
$400
$30o|
$3,510|
| Coupled PjoctiiModellivt 3.4
Coupled Process Modeling
$0
*soo
$*»
$500
$200
$200
$200
$200
$300
$300
$2,900
Therroomechanical Hydro'ogicat Benchmark Modeling
$250
5250
$1,550
$1,100
Process Coupling and Validation
S$P
$500
5300
$100
$100
$100
$100
5100
$200
Chemical
$200
$200
5100
$100
$100
$100
$100
$200
35 | IntUll j nd CoikI uct Fkld Tett Proof of Principle
$o| 52,300! $i,*oo| ?e,9ool $2,5oo| ?2,ioo| s?,«wl $?.iaol $2,»5ol $3,sso| $2«.60o|
Field Test installation and Operation*
' HeooriQstart FY15 - Accelerated coal down fly FY19
Instrumentation, Data Collectbn, and Testing
Alcove instrumentation Development and Procurement
¦ 7 Alcove oTTtrys and one redundant set
$200
$200
$1,900
Canister Heaters and Controllers Procurement
$750
Data Acquksttton System Procurement, Shakedown, and Calibration
$350
Fiber Optic System Procurement and 5hakedown for Data Transfer
$2S0
Underground Camera System Procurement and Shakedov/n
$200
Geophysical Assessment and Monitoring (e g , vapor movement!
$100
$200
$400
$100
$100
$100
$100
$300
$200
Instrumentation Shakedown, Calibration, and installation
$1,$50
Underground Testing Personnel (e g, data collection, active measurements)
$1,300
$1,100
$1,100
$1,100
$1,100
$600
Post-test Sample Collection Personnel
$450
$250
investigate Satt Properties of Test Bed Location
* Test ted specific investigations at WIPP
$200
$200
Field Test Scientific Management (e g Pis)
$300
$300
$300
$3O0
5300
$300
Construction and Ops Support
Mining - Access Drifts, Test Bed
* Presetvtttion of mining and hoist crew
stsoo
sisoo
Coring - Core Rig Purchase ~ tnstrumentCoring
*" Purchase or lease of new cor? rig
$ 1,700
Ventilation Control
$250
5250
$50
Dedicated Power installation
m New line to test bet/ area
$200
$200
$600
Safety Case and Work Control
$50
$SO
$50
Ops Support (e.g. access, utilities, heater installation}
" Over 50% Inf/ostfucxure costs saved at WIPP
$600
$600
$600
$600
S600
5700
5500
Test Forensics, Mine Back. Coring
51,500
$2,300
$750
$350
$250
$200
$1,600
$1,850
$6,300
$700
$1,SOO
$3,000
$1,700
$550
$1,000
$1$0
$4,200
$1,500
DOE-NE provided funding:
DOE-EM provided fundingr
Covered with Existing WIPP Labor/infrastructure:
TOTAL 501 BUDGET [nmw budgtt) NEEDED BY YEAR
TOTAL DISCRETE COST BY YEAR {including exiiting WIPP rtfourc**)
DOE-NE BUDGET [n*w budget) FOR THE TEST
DOE-EM BUDGET [n*w budget) FOR THE TEST
TOTAL DOE-EM COST [including existing WIPP r**ourc*s) FOR THE TEST
$700
$2,910
$4,000
$11,300
$4,350
$3,750
$3,750
$3,700 $4,850
$3,550
$42,860
$700
$4,410
$5,500
$11,300
$4,350
$3,750
$3,750
$3,700| $4,850
$5,050
$47,360
$700
$910
$2,000
*** Shared EM-NE cortt from FY14 to Complttion***
$0
$2,000
$2,000
$0
$3,500
$3,500
Salt Disposal Investigations
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Table 4-2: Cost by DOE Organization in FY12/FY13 (in thousands of dollars)
SDI Sect #| Talk/Product | FY11
FY12 ( FY13
DOE-NE Provided Funding
2.1 - 2.3 [Management, Quality Assurance, and Safety | $450
3.2 Bound Salt Ttiermomecharvkal Response $250 $400
$600
3.3 Laboratory Tests In Support of Modeling, PA, and the Field Test
$210 $700
3.4
Coupled Process Modeling
Thermomechanical-Hydrological Benchmark Modeling
$250
Process Coupling and Validation
$50
$500!
Chemical
$200
DOE-NE BUDGET |new budget) FOR THE TEST
$700
$910
$2,000:
DOE-EM Provided Funding
2.1-2.3
Management, Quality Assurance, and Safety
Project Mgmt, QA Support, Performance and Safety Analysis/Approvals
$600
$900
Detailed Test Plan Development
$400
2 A [international Collaboration
$200
S200]
3,5
Install and Conduct Field Test Proof of Principle
Instrumentation, Data Collection, and Testing
Alcove Instrumentation Development and Procurement
$200
$200
Geophysical Assessment and Monitoring (e.g., vapor movement)
$100
$200
Construction and Ops Support
Mining - Access Drifts, Test Bed
Ventilation Control
Dedicated Power installation
Safety Case and Work Control
DOE-EM BUDGET (new budget) FOR THE TEST
TOTAL DOE-EM COST (Including existing WIPP resources) FOR THE TEST
$o
SO
$1,500
$250
$200
$50
$2,000
$3,500
$1,500
$250
$200
$50
$2,000
$3,500
TOTAL SDI BUDGET (/lew budget) NEEDED BY YEAR
TOTAL DISCRETE COST BY YEAR (including existing WIPP resources;
$700
$2,910
$4,000
$700
$4,410
$5,500
: DOE-NE provided funding
: DOE-EM provided funding
: Resources Covered with Existing WIPP Labor/infrastructure
Salt Disposal Investigations
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Figure 4-1: Estimated Schedule for Test Program Duration (Constrained FY12/FY13 Scenario)
rfcr
SALT DISPOSAL INVESTIGATIONS - ESTIMATED TIME DURATIONS
15 ffSsTflari
T
"Ttr
11
id
IT
te
17
ie
19
¦sr
zr
22
2s
24
25
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26
29
30
~TT
3i
34
35
36
TT
38
39
40
41
TT
45
44
4S
47
49
£0
£1
£2
S3
£6
S7
SALT DISPOSAL INVESTIGATIONS
Field Stucfies
Test Planning and Preparation
QA Program De».«cpmsrrt
FunoDona 4 Opff&ans Requnsmens De.eopfnefll
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Salt Disposal Investigations
June 2011
62
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-------
4.2. MAJOR ACTIVITIES AND ACTIONS
Primary actions and test planning (FY11):
• Complete the SDI Management Proposal
• Complete a Test Plan for laboratory testing for crushed salt in the laboratory to measure
thermomechanical behavior across a variety of temperature, stress, and porosities
• Initiate laboratory tests on crushed salt
• Develop an NQA-1-compliant Quality Assurance Program Document and associated
procedures
• Complete the F&OR document for the field test
Test planning, initial mining and laboratory studies (FY12):
• Begin elevated temperature tests on intact salt in the laboratory to measure
thermomechanical behavior across a variety of temperatures and stresses
• Continue the laboratory tests on crushed salt
• Develop and review the detailed field test plan with equipment lists, instrumentation and
borehole layouts, data quality objectives, etc.
• Comprehensively evaluate existing and available information from past thermal
experiments
• Develop the criteria for the underground test design and layout
• Begin mining the underground access drifts to the test bed location
• Begin installing ventilation control and power distribution
• Write a test plan for laboratory studies of water liberation and brine migration in salt
• Begin measuring the thermodynamic properties of brines and minerals at elevated
temperatures in the laboratory
• Develop a test plan and begin measuring the effect of temperature on radionuclide
solubility in the laboratory
• Develop a test plan and begin studying repository interactions with waste container and
constituent materials in the laboratory
• Evaluate and use coupled multiphysics modeling capability for field test configuration
and analysis
Initial studies (FY13):
• Continue development of fully coupled TM(H) code and model for field test analysis.
• Continue laboratory thermomechanical testing and chemistry experiments
• Conduct laboratory studies of water liberation and brine migration
• Develop test plan for intact core testing in the laboratory
• Procure test equipment and instrumentation for the field test
• Develop work control and safety basis for the field test
• Complete mining of the underground access drifts
• Develop the documented safety analysis for the field test
• Mine the field test bed
Salt Disposal Investigations
June 2011
64
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Field test implementation (FY14):
• Core instrumentation boreholes
• Implement the field test equipment, including data collection equipment and fiber optic
communication equipment
• Investigate salt properties of test bed location
• Preparedness assessment for field test start and baseline measurements
• Continue laboratory thermomechanical testing and chemistry experiments
• Conduct laboratory studies of water liberation and brine migration
• Continued development of fully coupled TM(H) code and model for field test analysis
Conduct the proof-of-principle field test (FY15 - 20)
• Heating start on field test - FY 15
• Investigate thermal effects on intact salt in situ
• Develop a full-scale response for dry crushed salt
• Observe and document fracture healing in situ
• Track moisture movement and vapor phase transport in situ
• Complete laboratory thermomechanical testing and chemistry experiments
• Complete laboratory studies of water liberation and brine migration
• Cool down of field test by FY 19
• Post-test forensics, mine-back and post-test coring in FY 19 and FY 20
• Complete the final test and data reports
• Develop calibrated, coupled TM(H) model
Salt Disposal Investigations
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65
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5. REFERENCES
1. Beauheim, R. L., and R. M. Roberts, 2002. "Hydrology and hydraulic properties of a
bedded evaporite formation," J. Hydrol., 259, 66-88.
2. Blue Ribbon Commission on America's Nuclear Future. June 1, 2011. DRAFT -
Disposal Subcommittee Report to the Full Commission
3. Brodsky, N.S., F. D. Hansen, and T. W. Pfeifle. 1998. Properties of Dynamically
Compacted WIPP Salt Fourth Conference on the Mechanical Behavior of Salt
4. Carter, N. L., and F. D. Hansen, 1983. "Creep of Rocksalt," Technophysics, 92, 275-333.
5. Carter, J.T., F.D. Hansen, R. Kehrman, and T.A. Hayes. 2011. A Generic Salt
Repository for Disposal of Waste from a Spent Nuclear Fuel Recycle Facility. SRNL-
RP-2011-00149. Savannah River: Savannah River National Laboratory.
6. Clayton, D. J., and C. W. Gable, 2009. 3-D Thermal Analyses of High-Level Waste
Emplaced in a Generic Salt Repository, U.S. DOE Office of Nuclear Fuel Recycling
Report AFCI-WAST-PMO-DV-2009-000002.
7. DOE, 2010. "Blue Ribbon Commission on America's Nuclear Future: Advisory
Committee Charter."
8. DOE, 2011. "Memorandum of Understanding Between The Department of Energy Office
of Environmental Management and The Department of Energy Office of Nuclear Energy
for Used Nuclear Fuel and Radioactive Waste Management and Processing Research
and Development," April 29, 2011.
9. DOE, 2011. Salt Disposal Investigations Quality Assurance Program Document.
DOE/CBFO-11-3465. U.S. DOE Carlsbad Field Office.
10. Fehler, M. C., and L. Huang, 2002. "Modern imaging using seismic reflection data",
Annu. Rev. Earth Planet. Sci., 30, 259-84.
11. Gable, C. W., D. J. Clayton, and Z. Lu, 2009. Inverse Modeling to Determine Thermal
Properties of Salt due to Heating From High Level Waste Emplaced in a Generic Salt
Repository, U.S. DOE Office of Nuclear Fuel Recycling Report AFCI-WAST-PMO-DV-
2009-000001.
12. Geo. Cosmo. Acta., V73, pp 6544-6564.
13. Hansen, F.D., and C.D. Leigh. 2011. Salt Disposal of Heat-Generating Nuclear Waste.
SAND2011-0161. Albuquerque: Sandia National Laboratories.
14. Hansen, F.D., K. D. Mellegard, and P.E.Senseny. 1980. Elasticity and Strength of Then
Natural Rock Salts. Proceedings of the First Conference on the Mechanical Behavior of
Salt.
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15. IAEA, 2001. "The use of scientific and technical results from underground research
laboratory investigations for the geological disposal of radioactive waste," IAEA
Technical Document IAEA-TECDOC-1243.
16. Jenks, G. H. and H. C Claiborne, 1981. "Brine migration in salt and its implications in
the geologic disposal of nuclear waste," Oak Ridge National Laboratory Report ORNL-
5818,
17. Karlsruhe Institute of Technology. 2010, Proceedings.
18. Knauth, L. P., and M. B. Kumar, 1981. "Trace Water Content of Salt in Louisiana Salt
Domes," Science, 213, 1005-1007.
19. Knauth, L. P., M. B. Kumar, and J. D. Martinez, 1980. "Isotope Geochemistry of Water in
Gulf Coast Salt Domes," J. Geophys. Res., 85, B9, 4863-4871.
20. Koster van Groos, A. F. and S. Guggenheim. Dehydration of K-exchanged
Montmorillonite at Elevated Temperatures and Pressures, Clays Clay Miner. 34, 281-
286 (1986).
21. Letter, Marcinowski to Triay. EPA Approval for Experiments within WIPP. March 11,
2003.
22. Letter, Swift to McMahon, Stroud, and Hansen. New Direction for the Organization of
the Salt Disposal Investigations Activities. March 24, 2011,
23. Lundqvist, B., 2001. "The Swedish Program for Spent-Fuel Management," in P.A.
Witherspoon and G. S. Bodvarsson, eds., Geologic Challenges in Radioactive Waste
Isolation, Lawrence Berkeley National Laboratory report LBNL-49767, pp. 259-268.
24. Matalucci, R.V, 1987. In Situ Testing at the Waste Isolation Pilot Plant. SAND87-2382.
Albuquerque: Sandia National Laboratories.
25. McKinley, I., P. Zuidema, S. Vomvoris, and P. Marschall, 2001. "Swiss Geological
Studies to Support Implementation of Repository Project: Status 2001 and Outlook," in
P.A. Witherspoon and G. S. Bodvarsson, eds., Geologic Challenges in Radioactive
Waste Isolation, Lawrence Berkeley National Laboratory report LBNL-49767, pp. 269-
276,
26. Meunier. A,, Velde, B., and Griffault, L. (1998) The Reactivity of Bentonites: A Review.
An Application to Clay Barrier Stability for Nuclear Waste Storage. Clay Min., V33, pp
187-196.
27. MIT, 2011. The Future of the Nuclear Fuel Cycle, ISBN 978-0-9828008-4-3.
28. Mosser-Ruck, R., Cathelineau, M., Guillaume, D., Charpentier, D., Rousset, D., Barres,
O., and Michau, N. (2010) Effects of Temperature, pH, and Iron/Clay and Liquid/Clay
Ratios on Experimental Conversion of Dioctahedral Smectite to Berthierine, Chlorite,
Vermiculite. or Saponite. Clay and Clay Min,, V58, # 2, pp 280-291.
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June 2011
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29. National Academy of Sciences - National Research Council. The Disposal of
Radioactive Waste on Land. Washington, D,C. September, 1957.
30. National Academy of Sciences - National Research Council. One Step at a Time: The
Staged Development of Geologic Repositories for High-Level Radioactive Waste. 2003.
31. National Academy of Sciences - National Research Council. Waste Forms Technology
and Performance: Final Report, Committee on Waste Forms Technology and
Performance; National Research Council, ISBN: 0-309-18734-6, 2011.
32. Pfeifle, T. W., and L. D. Hurtado, 1998. "Permeability of natural rock salt from the Waste
Isolation Pilot Plant (WIPP) during damage evolution and healing," Int. J. Rock. Mech.
Mining Sci. Geomech., 35, 4, 637-638.
33. Rempe, N.T. 1998. "Negligible Environmental Consequences of Confined Underground
Nuclear Detonations as Positive, Beyond-Worst-Case Analogues for Deep Geological
Waste Isolation." International Conference on Radioactive Waste Disposal. DisTec'98.
Hamburg, Germany. ISBN 3-98066415-0-3.
34. Roedder, E., 1984. "The fluids in salt," American Mineralogist, 69, 413-439.
35. Roedder, E., and H. E. Belkin, 1979a. "Application of studies of fluid inclusions in
Permian Salado salt, New Mexico, to problems of siting the Waste Isolation Pilot Plant",
in McCarthy, ed., Scientific Basis for Nuclear Waste Management, Vol. 1, pp. 313-321.
36. Roedder, Edwin and Belkin, H.E. (1979) Fluid Inclusion Study on Core Samples of Salt
from the Ray burn and Vacherie Domes, Louisiana. United States Geological Survey
Open-File Report 79-1675, 25 p.
37. Roedder, Edwin and Belkin, H.E. (1980) Thermal Gradient Migration of Fluid Inclusions
in Single Crystals of Salt from the Waste Isolation Pilot Plant Site (WIPP). In C.J.M.
Northrup, Ed. Scientific Basis for Nuclear Waste Management, Vol. 2, p. 453-464. New
York, Plenum Press.
38. Sandia National Laboratories. 2010. US/German workshop.
http://www.sandia.gov/SALT/SALT_Home.html
39. Schuster, G., 1996. "Resolution Limits for Crosswell Migration and Traveltime
Tomography", Geophys. J. Int., 127, 427-440.
40. Stone, C.M., J.F. Holland, J.E. Bean, and J.G. Arguello. 2010. Coupled Thermal-
Mechanical Analyses of a Generic Salt Repository for High Level Waste. Salt Lake City:
American Rock Mechanics Association
41. U.S. NRC, 10CFR Part 51, V. 75, No. 246, Dec. 23, 2010. "Consideration of
Environmental Impacts of Temporary Storage of Spent Fuel After Cessation of Reactor
Operation".
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June 2011
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42. Vidal, O., and Dubacq, B, 2009. Thermodynamic Modeling of day Dehydration, Stability
and Compositional Evolution with Temperature, Pressure and H20 Activity.
43. Wu, T.C., Bassett, W.A., Huang, W.L., Guggenheim, S , and Koster van Groos, A.F.
(1997). Montmorillonite Under High H20 Pressure; Stability of Hydrate Phases,
Rehydration Hysteresis, and the Effect of interiayer Cations. Am Min, V82, pp 69-78.
Salt Disposal Investigations
June 2011
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APPENDIX B -
THE NEED FOR SALT DISPOSAL INVESTIGATIONS AND FIELD
TESTS (developed June 29, 2010)
thermal
Introduction
This brief memorandum recaps some of the reasons that
salt research is timely arid of national interest. The
proposal submitted to the DOE Office of Nuclear Energy
(NE) and Office of Environmental Management (EM)
senior management in February 2010 outlines a clear
process of advancing salt repository science beyond the
work done in the 1960s through the 1980s. The United
States has not advanced the notion of defense high-level
waste (DHLW) disposal in salt since these programs were
abandoned more than 20 years ago. Given the current
environment in the U.S. regarding future repositories, this
missive evaluates historical information, describes the gaps in our knowledge and then
advances an argument describing the need for a science-based research program that will
enable DOE to guide America's rational decision on future nuclear waste disposal options.
The administration's intent to reevaluate long-lived radioactive waste disposal in America, as
evidenced by the recently appointed Blue Ribbon Commission on America's Nuclear Future,
A science-based
research program
that will enable DOE
to guide America's
rational decision on
future nuclear waste
disposal options
B-1
-------
has motivated DOE to research geologic disposal solutions that do not directly link spent fuel
retrievable storage with the permanent disposal of HLW. Isolation in salt clearly remains a
robust geologic solution. Future considerations by DOE on decay and disposal of commercial
high-level waste fractions from recycling will benefit from research proposed to resolve the few
remaining key questions about thermally hot radioactive waste isolation in salt. These
investigations will necessarily leverage earlier work and build on an existing considerable
knowledge base about HLW storage and disposal in salt.
Why This Research Is Needed
Public understanding and confidence in permanent isolation of radioactive waste in salt have
improved as a result of a decade of successful disposal operations at WIPP. Directed research
and collaboration with international salt repository programs can help reduce identified
uncertainties regarding thermally-driven processes involved with radioactive decay and disposal
in salt and therefore further increase technical understanding for these potential missions. The
proposed work will build upon a foundation of excellence in salt repository applications that
began with the 1957 National Academies of Science recommendation to use salt for permanent
isolation of radioactive waste from the biosphere.
Year
Project
Location
Description
1965-1969
Lyons mine, Project Salt Vault
Lyons, Kansas
Irradiated fuel & electric heaters
1968
Asse salt and potash mine
Germany
Electric heaters
1979-1982
Avery Island
Louisiana
Brine migration
1983-1985
Asse (U.S./German
cooperative)
Germany
Brine migration under heat & radiation
1984-1994
WIPP
Carlsbad, New Mexico
1. DHLW Mockup
2. DHLW Over-test
3. Heated axisymmetric pillar test
Table B-1. Summary of in situ salt thermal tests
Table B-1 summarizes the history of in situ salt thermal tests both in the U.S. and internationally
over the past 50 years. A more detailed description of each program can be found at the end of
this paper. Despite this foundation, there are a number of important gaps in scientific
understanding of the thermo-mechanical and hydrologic-chemical behavior of radioactive and
thermally hot waste in a salt medium.
Consider the recent interview with a current member of the Blue Ribbon Commission on
America's Nuclear Future, on the subject of waste disposal in salt by Scientific American
(August 2009, "What Now for Nuclear Waste7'\ Matthew Wald, pp. 46-53):
Salt is nice, in some senses, from a geologic perspective. But if the salt is heated, the
watery inclusions mobilize and How toward the heat, so burying spent fuel there would
require waiting until the hot waste products cool down a bit—somewhere around the
second half of this century.
This demonstrates one of many mis perceptions about disposal in salt. The interviewee states
fluid inclusions migrate toward the heat source under a thermal gradient as a fact, yet there
remains great uncertainty in brine and vapor transport.
Previous in situ salt tests related to repository issues and operations were sufficient to advance
design for safe disposal of non-thermal TRU waste in salt; WIPP licensing and 10 years of
B-2
-------
operations have confirmed operational and performance expectations. Field heater tests as
outlined in Table B-1 have provided significant benefit to our knowledge of salt behavior,
however there are gaps that exist in the past experimental data that need to be addressed.
Advanced computer modeling and data gathering techniques used today are vastly superior to
the tools available 25 years ago. Regulatory and technical rigor is expected and necessary to
form defensible conclusions about the efficacy of salt as an efficient and effective disposal
media for thermally hot radioactive waste.
Things We Don't Know or Understand
Clearly, laboratory and field studies of the interaction of heat with salt have received attention in
the past. However, the upper temperature limit for the thermo-mechanical intact salt tests has
been about 200°C, and crushed salt and chemical interaction tests have been predominantly
conducted at room temperature. These past studies have been more than adequate to
demonstrate that disposal of TRU waste and moderate area I thermal densities of DHLW in salt
are safe and efficient. However, they do not provide the experimental data necessary to form a
defensible basis for policy, engineering, and performance assessment of salt outside our
experience with TRU waste.
Considering all of the existing experimental data from previous U.S. and German salt
investigations, a recent (May 2010) U.S./German Workshop on Salt Repository Research,
Design, and Operation began collaborations aimed toward identifying the current state of salt
repository sciences. From this workshop, several critical, unresolved issues with regard to salt
repositories were identified that should be addressed. The following issues and others will be
summarized in the workshop proceedings:
1. Brine migration — Brine inclusions may preferentially migrate up the thermal gradient
and corrode waste packages, but the transport process is unclear when inclusions reach
inter-grain boundaries, as welt as what happens when (if?) vapor phase transport
dominates;
2. Buoyancy — Thermally hot waste containers have been postulated to "melt downward,"
and the entire disposal horizon has been postulated to float upward due to buoyancy;
3. Heat associated with HLW disposal in salt — Heat-generating waste has been
characterized in 10 CFR 51 as exacerbating a process by which salt can rapidly deform,
which could cause problems for keeping drifts stable and open during the operating
period of a repository;
4. Solubility and transport — Radionuclide solubility in high ionic strength brines over wide
temperature ranges is much more complex than in unsaturated water, and research is
needed to describe leaching and transporting radionuclides;
5. Radiolysis — Further data are needed on the effect of radio lysis and temperature on the
speciation of waste constituents, brine chemistry, waste materials, waste packages, and
the salt.
A second US/German workshop on geochemistry and radiochemistry in salt repositories will be
held in Carlsbad in late summer aimed toward furthering international cooperation and
identifying the current state of knowledge and understanding of the chemistry in salt
repositories. The product of the two collaborative workshops will guide and support the Salt
Disposal Investigations (SDI) direction and focus.
B-3
-------
The Salt Disposal Investigations Proposal
The main reason to immediately conduct salt investigations leading up to and including a full
scale in situ heater test is that they will provide critical information on the efficacy and flexibility
of salt for the deep geologic disposal of thermally hot radioactive waste, building on the
momentum of the success of WIPP. As enumerated in detail in the SDI proposal, the specific
investigations will:
• Track moisture movement and vapor phase transport in situ.
• Observe and document fracture healing in situ.
• Measure the salt thermomechanical response.
• Investigate thermal effects on intact salt in situ.
• Study repository interactions with waste container and constituent materials.
• Develop full-scale response for dry, crushed salt.
• Demonstrate a proof-of-principle disposal in salt concept.
• Apply laboratory research to intact and crushed salt.
• Measure the thermodynamic properties of brines and minerals at elevated temperatures.
• Measure the effect of temperature on radionuclide solubility.
Summary
Underlying the in situ testing and supporting laboratory research is the hypothesis that heat-
generating waste can actually be advantageous to permanent disposal in salt. The ~300-year
thermal pulse introduced by spent fuel or high-level waste may dry out a moisture halo around
emplaced waste and thereafter accelerate entombment and salt healing by thermally activating
the creep processes. At the same time, any very long-lived isotopes also present will be
permanently encapsulated in a geologic formation that has demonstrably been hydrologically
inactive for hundreds of millions of years, thereby potentially precluding the need for engineered
barriers, including vitrification for disposal.
Directed research will inform, guide, and ultimately define requisite capabilities for the next
generation of coupled multiphysics modeling, which in turn will be instrumental for development
of performance assessment methodology. Building on the impressive performance and
knowledge base developed for defense TRU waste disposal at WIPP, this research will identify
specific requirements for a potentially viable long-term decay storage and deep geologic
disposal concept for HLW in salt. These key elements will translate into parameters and
phenomena to be measured in a proof-of-principle field test, which crowns the proposed effort.
The proposed research, development, and demonstration of salt efficacy for the safe and
efficient disposal of thermally hot waste will provide the basis for a repository that can readily
isolate vast quantities of nuclear waste material, providing a key component of a safe and
secure nuclear future for the nation.
B-4
-------
References to Appendix B:
US/German Workshop on Salt Repository Research, Design, and Operation, Hosted by M.
Horstemeyer Mississippi State University, A. Orrell Sandia National Labs, F. Hansen
Sandia National Labs, 2010, [http://www.sandia.gov/SALT/SALT_Home.html]
K. Kuhn, Field Experiments in Salt Formations, Philosophical Transactions of the Royal Society
of London. Series A, Mathematical and Physical Sciences, Vol. 319, No. 1545, 1986
A. M. Starfield, W. C. McClain, Project Salt Vault: A Case Study in Rock Mechanics,
International Journal of Rock Mechanics and Mining Science & Geomechanics Abstracts, Vol.
10, 1073
R. V. Matalucci, In Situ Testing at the U.S. Department of Energy's Waste Isolation Pilot Plant,
Tunnelling and Underground Space Technology, Vol. 5, No. 1/2, 1990
F. Hansen, Assessing Engineered Systems in Geologic Repositories: WIPP, Presented at the
Performance Assessment Community of Practice Workshop, Salt Lake City, Utah, July 13-14,
2009 [http://www.cresp.org/PACOP/index.html]
F. Hansen, Path Forward investigations for Generic Salt Repository High-Level Waste Disposal
Proof-of-Principle Concepts, Sandia National Laboratories, Carlsbad, NM. ERMS 549032.
A. Hull and L. Williams, Radioactive Waste Isolation in Salt; Geochemistry of Brine in Rock Salt
in Temperature Gradients and Gamma-Radiation Fields - A Selective Annotated Bibliography,
Argonne National Laboratory, Argonne, IL., ANL/EES-TM-290, 1985
B-5
-------
History of Salt Disposal Research for Thermally Hot Waste
Previous in situ salt tests related to repository issues and operations were sufficient to advance
design for safe disposal of non-thermal TRU waste in salt; WIPP licensing and 10 years of
operations have confirmed operational and performance expectations. However, disposal of
heat-generating waste in salt gives rise to thermally driven processes that require investigation
before a concept for disposal of such waste can be confidently developed. The need for
additional, science-based testing to fortify the technical baseline supporting HLW disposal builds
upon a considerable data base deriving from historical experiments. For example, field heater
tests in salt were conducted in Project Salt Vault in Kansas in the 1960s and in WIPP in the
1980s. These field tests provide significant benefit to our knowledge of salt behavior; however,
some gaps can be identified that have not been sufficiently resolved. The requisite studies in
the SDI proposal derive from two main focus areas: one area comprises equivocal issues and
technical gaps arising or remaining from the historical testing, while the other focus area takes
advantage of the significant computational tools and capabilities available today that simply did
not exist when the field tests were conducted a generation ago. Building upon past experiences
and taking advantage of advanced technology allow the formulation of a solid, task-oriented,
progressive proposal to address the remaining issues for HLW disposal in salt. The research,
development, and in situ heater test demonstration will specifically provide the basis for decision
making concerning long-term decay storage and deep geologic disposal of thermally hot
radioactive waste in salt.
The following synopsis includes field experiments in salt formations that started as early as
1965 with Project Salt Vault near Lyons, Kansas, and nearly contemporaneous field testing and
demonstration at the Asse salt mine in Germany. Underground tests concentrated on heat
dissipation and geomechanical response created by heat-generating elements placed in salt
deposits. The following is a brief history of heated in situ testing in salt:
1957 The National Academy of Sciences/National Research Council (NAS/NRC) of the United
States published a study on radioactive waste disposal on land, proposing for the first time the
use of geological formations, especially rock salt.
1905-69 The first integrated field experiment for the disposal of HLW was performed by Oak
Ridge National Laboratory (ORNL) in bedded salt near Lyons, Kansas. This test, named Project
Salt Vault (PSV), used irradiated fuel assemblies from the Engineering Test Reactor at Idaho
Falls as a source of intense radioactivity, while electrical heaters were placed in boreholes in the
floor to simulate decay heat generation of HLW. The tests simulated the heat flowing into the
base of the pillar from a room filled with waste with the primary focus on rock mechanics of floor,
ceiling, and pillar deformation. These pioneering tests with live spent fuel and simulated
electrical heaters produced modest pillar temperatures of less than 50°C. The tests did
concentrate on potential structural effects of radiation {there were none). Significant brine
accumulation was observed after the electrical heaters were turned off, which initiated the
lingering issues of moisture behavior in such a setting. Possible brine inclusion migration and
vapor transport phenomena have not been completely resolved by field experiments.
1968 A field experiment with electrical heaters was performed in the Asse salt mine to
investigate the near-field consequences of emplaced HLW. These early experiments on the
disposal of HLW at Asse evaluated thermomechanical properties of the Stassfurt Halite. Later
on, operational options investigated included vertical borehole disposal of steel canisters and
horizontal placement of steel casks surrounded with backfill crushed salt. The system was
approved by the responsible mining authority. In all, three large-scale "heater" experiments
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were performed in the Asse mine, which yielded important data for the validation of material and
computer models needed to assess the coupled long-term behavior of rock salt and crushed
salt backfill in a salt repository. The Asse experiences provided important lessons and guidance
for future testing which can be used in corroborating the lower temperature range of the SDI.
1979 Also in Germany, the Gorleben salt dome has been investigated since 1979. In 1998, the
German government expressed doubts with respect to the suitability of the Gorleben host rock.
All exploration activities were halted by the end of 2000, and a moratorium was imposed. The
moratorium ends in 2010, so German repository scientists are poised to restart salt repository
investigations. Like the salt testing in the U.S., German research provides a wealth of
information on salt disposal investigations, which has been and will be considered in
collaboration efforts, as described in the SDI proposal.
1979-82 Brine migration tests were performed by RE/SPEC for the Office of Nuclear Waste
Isolation (ONWI) in the Avery Island salt mine in Louisiana. The migration of brine inclusions
surrounding a heater borehole were studied on a macroscopic level by investigating gross
influences of thermal and stress conditions in situ. Field tests were augmented in the laboratory
by microscopic observations of fluid inclusion migration within an imposed thermal gradient.
The maximum temperature reached in the field test was only 51 °C. Moisture collection was
minimal during heating, amounting to grams of water per day. When the heaters were shut off,
cooling caused changes in tangential stress, which led to microcracking, opening of grain
boundaries, and moisture release. Much of the moisture released was a result of cooling from
turning off the heaters, which drastically reversed the thermal gradient; this would not occur in a
HLW repository.
1983-85 A bilateral U.S.-German cooperative Brine Migration Test in the Asse salt mine
investigated the simultaneous effects of heat and radiation on salt. This field experiment used
0OCo sources with a total radioactivity of about 36,000 Ci. Test configuration included four
identical heater arrays. The maximum temperature in the borehole was 200CC. Results of this
test will be used to guide instrumentation selection and assessment of brine and vapor phase
moisture movement in the proposed SDI field investigations. Contemporaneous German
research is keenly interested in moisture movement, and they continue to analyze the specific
brine and vapor migration experiments. These data and observations will be considered in test
configuration, instrumentation, and methodology.
1984-1990 Three separate simulated heater tests were performed at WIPP: 1) 18W/m2 DHLW
mockup; 2} DHLW over-test; and 3) the Heated Axisymmetric Pillar test. The 18W/m2 DHLW
mockup and DHLW over-test were designed to identify how the host rock and the storage room
respond to the excavation itself and then to the heat generated from waste placed in vertical
holes in the drift floor. These field tests imparted a relatively modest thermal load in a vertical
borehole arrangement and did not use crushed-salt backfill or explore reconsolidation of salt.
These tests were primarily focused on the mechanical response of the salt under modest heat
load. Although the results can be used, for example, to validate the next-generation high-
performance codes over a portion of the multiphysics functionalities, the SDI disposal concept
would need to explore the interactions created by higher heat loads, a horizontal placement and
crushed-salt backfill. The Heated Axisymmetric Pillar test involved an isolated, cylindrically-
shaped salt pillar and provides an excellent opportunity to calibrate scale effects from the
laboratory to the field, as well as a convenient configuration for computer model validation over
a small part of the thermomechanical range of interest. These experiments provide a
foundation for the low temperature range of SDI investigations, as described in the general
proposal.
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APPENDIX C - KEY CONTRIBUTORS TO THE SDI PROPOSAL
U.S. Department of Energy - Carlsbad Field Office
Roger A. Nelson - Chief Scientist, Waste Isolation Pilot Plant
Roger Nelson has almost 40 years of experience managing and conducting environmental
programs for public and private sector projects. As Chief Scientist for WIPP over the past
ten years, he serves as the project principal technical/scientific advisor. His focus is on
identification and development of innovative and cost-effective waste handling, treatment,
characterization, packaging, transportation, and disposal technologies. He promotes use of
the unique underground environment at WIPP for use as a laboratory for basic science
experiments requiring extremely low dose rate background radiation. He also champions
WIPP in national and international waste management venues.
Sandia National Laboratories
Dr. Frank D. Hansen
Dr. Hansen has over 30 years of experience in repository sciences and has contributed
significant original research in rock mechanics, seal systems, materials, design, and
analysis. He is a distinguished member of the technical staff at Sandia National
Laboratories, a registered professional engineer, and an ASCE Fellow.
Los Alamos National Laboratory
Dr. Ned Z. Elkins
Dr. Elkins has 35 years of experience in mining salt, potash, coal and metals, mine/refinery
design and management, and nuclear waste geologic disposal programs in Nevada and
Carlsbad, New Mexico. He managed the underground facility design of testing
infrastructure and was responsible for implementation of the overall geotechnical field
testing program for Yucca Mountain from 1989 to 1998, and he subsequently managed
SNL's WIPP Program Group in Carlsbad from 1998 to 2000. Since 2000, Dr. Elkins has
established and manages the Los Alamos Carlsbad Operations and Program Office in
support of WIPP and the National Transuranic Waste Program.
Timothy A. Hayes
Tim Hayes has over 25 years of experience in actinide science with LANL. His career at
LANL has given him experience performing and managing technical operations in a nuclear
facility such as: actinide recovery and purification, advanced technology development for
nuclear materials disposition and handling, manufacture of actinide-containing components,
waste management, nuclear material shipping and transportation, nuclear facility safety
basis, and nuclear material control and accountability. He has held management positions
as Division Leader of Stockpile Manufacturing, Group Leader of Nuclear Material Security
and Accountability, Deputy Group Leader of Radioactive Waste Management, and Team
Leader of Actinide Processing and Challenging Waste Disposition.
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Dr. Bruce A. Robinson
Dr. Bruce Robinson has served as the Program Manager of LANL's Yucca Mountain Project
and as the Deputy Division Leader of the Earth and Environmental Sciences Division. In
repository science, he was the lead author of the Yucca Mountain License Application
section on Radionuclide Transport in the Unsaturated Zone. His personal research interests
include: nuclear waste disposal; groundwater characterization and modeling; flow and
transport in porous media; and optimization and inverse modeling. He is the author of 50
peer-reviewed journal publications.
Clifford D. Stroud
Cliff Stroud has 25 years of experience in nuclear waste geologic disposal programs and
management. This has included work abroad, throughout the United States, with the
Congress in Washington, D.C., and with each Energy Secretary. He has played a key
management role with LANL in decayed storage or permanent isolation of radioactive waste
in salt resulting in more than a decade of successful disposal operations at the WIPP.
Douglas J. Weaver
Doug Weaver is a mechanical engineer at LANL with nearly 20 years of experience
conducting and managing large scale testing programs. He served as the project engineer
for a series of thermal tests at Yucca Mountain that included a large block heated test, an
underground single heater test, and the largest underground thermal test in the world, the
YMP Drift Scale Test. Doug later managed the Yucca Mountain Project Test Coordination
Office responsible for all surface-based and underground testing on the Project, including
large geotechnical drilling programs and performance confirmation monitoring.
Washington TRU Solutions
Dr. Stanley J. Patchet
Dr. Patchet is a Professional Engineer and Manager of Mine Engineering for Washington
TRU Solutions at the WIPP.
RESPEC
RESPEC Consulting & Services are world experts in the areas of salt mechanics, rock salt
testing, and field services. RESPEC's materials testing laboratory is the largest and one of
the best equipped laboratories in the world for studying rock salt. Among many notable
tests, RESPEC performed the geotechnical engineering characterization for the Deep
Underground Science and Engineering Laboratory (DUSEL) in the former Homestake Mine
located in Lead, South Dakota. Laboratory tests described in this proposal will likely be
conducted in RESPEC laboratories and as such, RESPEC staff provided input and review of
the laboratory thermal and mechanical studies section of this proposal.
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Enclosure 3
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The Nuclear Safety Impact Analysis on the Salt Disposal Investigations (SDI)
The salt disposal investigations (SDI) include a science-based scope of work incorporating both field and
laboratory tests. The use of the WIPP underground for the field test portion of the SDI directly tests a
safe disposal arrangement in the salt formation that balances heat loading with high level waste
temperatures. It is anticipated that underground test bed will be heated to temperatures well above
those for which current salt experimental data exist The test program will provide knowledge of the
behavior of thermally and radioactively high level nuclear waste in salt and support the hypothesis that
the thermal pulse imparted by high level waste on salt leads to rapid encapsulation. The test bed will
utilize the north area of the mine initially used for evaluating the interaction of simulated waste and
thermal sources on bedded salt under controlled conditions. (Clayton and Gable, 3-D Thermal Analyses
of High-Level Waste Emplaced in a Generic Salt Repository, February 2009)
The Salt Disposal Investigations Impact on the Probability of Occurrence of an Accident
The proposed SDI to determine how salt reacts to temperatures over 100 to 200 degrees Celsius will not
increase the probability of occurrence of an accident as previously analyzed in the WIPP safety analysis
The test bed will be located in the north experimental area of the WIPP underground, a few hundred feet
south of the N-1100 drift and away from waste handling activities, equipment important to safety and
waste disposal activities.
The WIPP DSA is required to consider a minimum set of hazard event scenarios which includes, fires
explosions, loss of confinement, direct radiation exposure, criticality, and externally initiated and natural
phenomena. The SDI does not involve material at risk, waste handling, or the use of equipment
important to safety that would be impacted by the hazard event scenarios previously analyzed in the
WIPP Documented Safety Analysis (DSA). Therefore, accidents previously analyzed or the occurrence of
a new accident that could result in a release of radioactive material is not applicable to the SDI,
Could the proposed activity or potential inadequate safety analysis (PISA) increase the
consequences of an accident previously evaluated in the existing safety analysis?
When establishing a new scientific investigation in the WIPP underground consideration must be given to
potential consequences from accidents involving radiological exposure or a release of radioactive
material to facility workers, collocated workers, and the public. Potential radioactive material releases or
exposure are not applicable in this situation because the SDI field tests will be a mock-up with electrical
heaters in place of radioactive materials. The spacing between heaters is intended to bound thermal
conditions for radioactive disposal operations. The field tests will be located in the north experimental
area of the underground where no radioactive waste is present.
Could the proposed activity or PISA increase the probability of occurrence of a malfunction of
equipment Important to safety previously evaluated in the existing safety analysis?
The proposed SDI will not increase the probability of a malfunction of equipment important to safety
because the proposed location of the test bed is located far north of the waste disposal operations where
other scientific experiments are being conducted. The SDI will have no impact on systems structures,
and components (SSCs) along with safety-related SSC described in the WIPP safety analysis. The area
is already configured with electrical power and cabling and interaction with equipment is also prevented
by a two drift access drift. Cross-cuts will provide access/egress to the new test pillar as well as sufficient
controlled ventilation to maintain reasonable conditions for personnel near the test bed.
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Could the proposed activity create the possibility of an accident of a different type than any
previously evaluated in the existing safety analysis?
The WIPP safety basis evaluated potential accident initiators that could result in the loss of confinement
of a waste container caused from fires, drops, explosions, collisions, and natural phenomena. Since the
closest panel to the experimental area is Panel 1, which is located south of S1600 at E300 approximately
700 meters from the proposed site of the SDI, there is no possibility of interacting with the waste, waste
disposal activities, or waste handling equipment According to a summary of calculations presented in
AP-156, Thermal Analysis Report, Rev. 0, SDI Heater Testing Long-Term thermal Effects Calculation,
dated May 27, 2011, two years use of five 8500 Watt heaters in the SDI thermal testing will have
insignificant effects on the thermal state at the location of the waste disposal panels. The proposed
testing of high thermal loading effects in bedded salt is not an accident initiator and because of the
remote location of the experiment, does not create the possibility of an accident of a different type than
any previously evaluated in the existing safety analysis.
Could the proposed activity create the possibility of a malfunction of equipment important to
safety of a different type than any previously evaluated in the existing safety analysis?
The SDI will have no interaction with waste handling equipment or safety-related equipment important to
safety. Therefore the possibility of a failure or malfunction of equipment important to safety of a different
type than previously evaluated in the existing safety analysis is not applicable.
Could the proposed activity reduce a margin of safety?
Functional requirements and design of safety class and safety significant SSCs are identified in the WIPP
safety analysis and are protected by controls established in the WIPP Technical Safety Requirements
(TSRs). The SDI has no impact on the WIPP DSA, TSRs and their bases, or the design or functional
performance and reliability of equipment important to safety as described in the WIPP safety basis.
Therefore, there is no reduction in a margin of safety.
Conclusion
The SDI research program will have no impact on the waste disposal operations in the WIPP
underground. However, if approved, WIPP DSA would require updating to include description of the new
test and scope. Work on the project including mining could proceed once the unreviewed safety question
determination is completed. The WIPP DSA can be updated subsequent to starting the work.
Page 2of 2
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Enclosure 4
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555^2Z
Analysis Report
AP-1S6 Revision §
SDI Heater Testing Long-Term Thermal Effects Calculation
(AP-156: Analysis Plan for the Impact Determination of
SDI Heater Testing on Long-Term WIPP Performance)
Task Number 1.4.2.3
Report Date: May 27,2011
Technical Review:
t
James Pasch
Performance Assessment Department (6211)
Steve Davis
Carlsbad Programs Group (6210)
: 5/3-l/l
Author; £ ^^"** M/r- Date:. IIMIK
Kris Kuhlman
Repository Performance Department (6212)
^ l[M(/ Ar Date:SfzllI(
QA Review: QP'A^/1 /dM&k _ Date: miw
Management Review / U\s\ Dale
Moo Lee
Performance Assessment Department (6211)
to IPP ' =5 > ^ > -
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Contents
SDI Heater Testing Long-Term Thermal Effects Calculation 1
1.0 Introduction and Objectives 3
2.0 Thermal Impacts Summary 3
2.1 Thermal Effects Screening Calculation 4
2.2 Heat conduction solution: results,... 5
2.3 Analytic heat conduction solution: assumptions and limitations 7
3.0 Summaiy 9
4.0 References 9
5.0 Python Script Listing 10
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1.0 introduction and Objectives
The Waste Isolation Pilot Plant (WIPP), located in southeastern New Mexico, has been developed by
the U.S. Department of Energy (DOE) for the geologic (deep underground) disposal of transuranic
(TRU) waste. Containment of TRU waste at the WIPP is regulated by the U.S. Environmental
Protection Agency (EPA) according to the regulations set forth in Title 40 of the Code of Federal
Regulations (CFR), Part 191. The DOE demonstrates compliance with the containment requirements
according to the Certification Criteria in Title 40 CFR Part 194 by means of performance assessment
(PA) calculations performed by Sandia National Laboratories (SNL). WIPP PA calculations estimate
the probability and consequence of potential radionuclide releases from the repository to the accessible
environment for a regulatory period of 10,000 years after facility closure. The models are maintained
and updated with new information as part of a recertification process that occurs ait five-year intervals
following the receipt of the first waste shipment at the site in 1999.
With the recertification of the WIPP in November of 2010 (U.S. EPA 2010), a new PA baseline was
established by the PABC-2009. Following this most recent recertification decision, the DOE plans to
submit a planned change notice (PCN) to the EPA that justifies additional excavation in the WIPP
experimental area. This excavation will be done in order to support salt disposal investigations (SDI)
that include field-scale heater tests at WIPP.
The proposed expansion of the WEPP experimental area in order to facilitate SDI work requires an
assessment of the impact of planned heater tests on the thermal state of the repository at the time of
closure must be evaluated and quantified. The DOE has requested that SNL undertake calculations and
analyses to determine the impacts of planned heater tests will be via an assessment of the evolution of
heat dissipation from the beginning of SDI experimental work to the time of facility closure. Analysis
plan AP-156 outlines the approach SNL will use to determine the impacts of the planned additional
excavation and heater tests in the WIPP experimental area on long-term repository performance.
2.0 Thermal impacts Summary
An analytic heat conduction solution is used to conservatively estimate the rise in temperature at the
WIPP waste disposal panels due to the proposed SDI heater tests. The calculation uses a well-known
two-dimensional analytic solution and the method of superposition. These solutions and methods are
found in heat conduction textbooks: for example Ozisik (1993), and Carslaw and Jaeger (2003). The
solution is analytic (there is no computational grid, time steps, or solver) and uses the simple mathe-
matical concept of superposition to find the resulting expected rise in temperature. The advantages of
an analytic solution include the lack of ancillary parameters related to numerical solution (e.g., grid
spacing, time steps, and convergence criteria). In this case an analytic solution will capture the con-
servative bounding nature of the proposed calculation without the complications introduced by a poten-
tially more realistic gridded numerical model.
Superposition is used to take a simple two-dimensional solution and build up a solution that considers
both the timing and geometry of the proposed SDI heater tests. Superposition is possible due to the
linearity of heat conduction in a solid (with constant thermal properties). The analytic solution will ig-
nore the effects that the excavations or any small-scale heterogeneity would have on the solution. The
drifts may be circulated with relatively cool air, and would therefore serve as a sink for heat during the
operational life of WIPP. This potential cooling effect will not be taken into account in the proposed
supeiposition of analytic solutions.
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The calculation begins with a solution for a line source with cylindrical symmetry. Wc use superposi-
tion in time of a co-located source and sink to simulate a finite source (in this case 2 years). The eff ect
of anhydrite Marker Beds 138 and 139 (above and below the repository, respectively) arc what make
the solution two-dimensional, treating them as if they are perfectly insulating boundaries. In a purely
homogeneous and isotropic medium with spherical symmetry, heat flow would be three-dimensional
(x, y and z). Accounting for the marker beds will be quite conservative, forcing the heat to flow in a
two-dimensional manner (x andy only).
Superposition in time will produce a field of predicted temperature rise due to one heater. The effects
of all five of the proposed heaters will be estimated by superimposing the required number of these line
solutions at the proposed heater locations, (x and y); this final superposition will determine the ex-
pected total rise in temperature due to all proposed heaters at any location in space or time after the
heaters are turned on.
This report documents the calculation, material properties, and temporal and geometrical arrangement
used. Section 5 lists the Python script used to compute and plot the solution, allowing the calculations
to be checked and verified. Any deviations from details in the analysis plan were related to corrections
and comments received in the review process; the approach used in this report is conceptually simpler
while effectively the same as that in AP-156.
2.1 Thermal Effects Screening Calculation
A bounding-type calculation has been performed to evaluate the effects proposed SDI heaters would
have on the long-term compliance performance assessment of the WIPP. The discussion of the results,
assumptions, and limitations for the analytic solution are given below. The listing of the calculation
and plotting script are presented in the following sections.
The heat conduction solution used is for a specified flux at a line source, assuming angular symmetry
for each heater. The solution for temperature rise, T, is well known and is presented in Cars law and
Jaeger (2003), section 10.4 (p. 261) as
where Ei() is the exponential integral, q = tppC is the strength of the line source per unit length in the
z-direction,
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QtH = pVCAT
where Q is the heater strength [8500 W = 8500 J/s], tH is the length of time the heaters are on [2 yr =
6.312E+7 s], V is the volume of salt the energy is being distributed across [7t(700 m)2-16.67 m =
2.566E+7 m3], and AT is the resulting average temperature rise across the volume V [K], Using this
relationship, the expected temperature rise due to five 8500 W heaters for two years over a cylindrical
block 700 m x 16.67 m is 5,13E-2 K.
2.2 Heat conduction solution: results
The analytic solution allows the calculation of the predicted rise in temperature at any time after the
heaters are turned on (the temperature rise is zero before they turn on). Figure 1 shows the predicted
temperature rise due to the five 8,500 Watt heaters being on for two years at six different distances
from the center of the constellation of five SDI experiment heaters. The distance to Panel 1 from the
center of the SDI heater drift is approximately 700 meters (corresponding to the lowest curve in Figure
1).
&
£ 1Q-*
10 7
10"1 10° 101 102 103 104 10s
time since heaters turned on [yrs]
Figure 1. Predicted temperature rise through time (due to two years of heater tests) at six radial
distances from proposed SDI experiment.
Figure 1 shows that the predicted peak temperature rise arrives at later times when observed from
greater distance from the heaters. This is a simple well-known result from diffusion. At the distance
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Panel 1 is from the SDI experiment, the peak temperature is very small (~ 0.02 K) and arrives very late
(>1,000 yrs). This prediction is a bounding conservative calculation (see following discussion of
assumptions and limitations of this approach).
distance from center of SDI area [m]
Figure 2. Predicted temperature rise profile (due to two years of heater tests) at five times after heaters
are turned on (2013) from proposed SDI experiment.
2
3
2
a>
a.
E
0)
Figure 2 shows the predicted spatial profile of the temperature rise At late time, the distribution of
temperature rise becomes very uniform; the solution is close to the energy balance calculation in
Section 2.1 (a uniform 0.05 K rise). After approximately 70 years the residual rise at almost all
locations are at or below IK. The assumptions and limitations of the analytic solution used to compute
these results are given in the next section.
Figure 3 shows the predicted spatial distribution of the temperature rise 22 years after the beginning of
heater tests (2035), which is the starting time for WIPP performance assessment calculations.
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Accm Drifts a a33 ftMt e W w U' Nflh, 130 04ft ton*
Figure 3. Predicted temperature rise distribution (due to two years of heater tests) at 2035,22 years
after heaters are turned on (2013) from proposed SDI experiment.
2.3 Analytic heat conduction solution: assumptions and limitations
The linear conduction of heat in a homogeneous isotropic solid is governed by the diffusion equation,
and is covered in any textbook on heat transfer, diffusion, or conduction (e.g., lncropera & de Witt
(1985), Carslaw & Jaeger (2003), Ozi§ik (1993), or Crank (1985)). The salt in the underground facility
at the WIPP deviates from the ideal circumstances in four main ways. These deviations are secondary
effects or would lead to a less conservative result, and therefore the analytic solution is valid for a
conservative screening calculation. The solution assumes homogeneous and linear properties, aside
from the geometry handled through superposition. The most significant assumption is that heat
conduction is the only mechanism to dissipate thermal energy introduced by heaters. Each of the
deviations from the ideal conditions is discussed below, indicating how they were addressed, or
explaining the ramifications of not addressing them,
1) The excavations within the salt do not contribute to the conduction of heat. Air-filled excavations
have much lower thermal conductivity than intact salt and would essentially act as insulating
boundaries for conduction (although radiation and convection would likely be significant heat transfer
processes). By volume, the excavations are minor compared to the amount of salt available for
conduction. Near the heaters, including the location and shapes of the excavations would be important
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for predicting the temperature of the salt. At 700 m the effects of the excavations are of much less
importance. Ignoring the thermal conductivity effects of the excavations does not necessarily lead to a
more conservative estimate. Taking into account the heat transfer properties of excavations would
preclude the use of a straightforward analytic solution.
2) The mine ventilation system will remove some thermal energy. During testing some drifts will be
closed off to allow thermal energy to build up in the salt. The proposed design relies on the ability of
the mine ventilation system to cool the drifts to a temperature low enough for human entry. The energy
removed during convection of relatively cool air through the drifts is assumed to still be trapped in the
salt, and must be dissipated by conduction.
When the test area is ventilated, thermal energy will be removed by convection and the salt will be
cooled. This is the intention of ventilating the SDI experimental area. When the salt is cooled, the
local thermal gradient will actually reverse, and heat will now flow towards the original heat source
area, which is now a heat sink. This reversal is not accounted for in the analytic solution, and it is
therefore considered a quite conservative estimate.
3> Thermal conductivity for W1PP salt is not constant. The straightforward analytic solution of the heat
conduction problem is only possible when thermal conductivity is a constant. The variability of
thermal conductivity over the range of expected temperature is less than an order of magnitude;
specifically, thermal conductivity of halite at WIPP is given as (Stone et al., 2010)
where k is thermal conductivity [W/(m*K)] and T is temperature [K]. It is considered to be a
conservative approximation to use the highest value of thermal conductivity expected over that range,
specifically A(7^=300 K) = 5.4 W/(m*K). The volume of salt immediately surrounding the heater will
have lower thermal conductivity than the far field, because of much higher temperatures; this will slow
the flow of energy away from the heaters by conduction.
4) WIPP salt is not homogeneous and isotropic. The Salado formation consists of laterally extensive
nearly horizontal layers of mostly halite, some anhydrite, minor clay, and minor other evaporites. The
Salado formation has a much greater horizontal extent (tens to hundreds of kilometers) than vertical
extent (few hundred meters). Any thermal pulse would encounter boundaries in the vertical direction
much sooner, than in the horizontal directions. Halite has higher thermal conductivity than other
materials found in the Salado (e.g., see point 5 on page 4 of DOE 201 lb). A conservative prediction
assumes these anhydrite marker beds just above and below the repository are perfectly insulating. In
reality, the marker beds are only less conductive than halite, and there is a large thickness of halite both
above and below these thin marker beds.
The analytic solution accounts for these maker beds by simulating the domain as being two
dimensional. The vertical extent (approximately 16 meters) is much less than the horizontal extent
(hundreds to thousands of meters) and therefore the two-dimensional approximation is conservative
and accurate enough for the desired purpose. The analytic solution does not account for any other
heterogeneity or anisotropy of thermal properties, aside from the insulating boundaries at the marker
beds.
Although neglecting the excavation's effects on heat conduction is not handled in a conservative
manner (point #1 above), it is believed that not taking credit for the heat lost to mine ventilation (#2)
and conduction above and below the marker beds (#4) leads to a very conservative estimate of
temperature rise at Panel 1. The overall result is conservative in its assumptions and shows that the
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SDI heater experiments should create no discernable deviation from the current baseline condition at
the WIPP.
3.0 Summary
The effects of two years of five 8500 Watt heaters in the SDI thermal tests will be insignificant at the
location of the waste disposal panels(Panel 1 being the closest) for any time. The calculation in this
report is very conservative and bounding; the results illustrate that even under such conservative
estimates there is expected to be no change in repository conditions at the time the WIPP repository is
planned for closure, based on the preliminary design presented in the letter and proposal from DOE
(2011a; 2011b).
4.M References
R. L. Beauheim and R.M. Roberts. Hydrology and hydraulic properties of a bedded evaporite deposit.
Journal of Hydrology, 259(l-4):66~88,2002.
H. Carslaw and J. Jaeger. Conduction of Heat in Solids. Oxford Science, second edition, 2003.
J. Crank. The Mathematics of Diffusion. Oxford Science, second edition, 1985.
F. P. Incropera and D. P. De Witt. Introduction to Heat Transfer. Wiley & Sons, 1985.
M. N. Ozifik. Heat Conduction. Wiley Interscience, second edition, 1993.
U.S. Environmental Protection Agency (EPA). 2010. 40 CFR Part 194 Criteria for the Certification and
Recertification of the Waste Isolation Pilot Plant's Compliance With the Disposal Regulations:
Recertification Decision, Federal Register No. 222, Vol. 75, pp. 70584-70595, November 18,
2010.
U.S. Department of Energy (DOE) 2011a. Direction Letter for SDI Field Testing Planned Change
Notice. U.S. Department of Energy Waste Isolation Pilot Plant, Carlsbad Area Office, Carlsbad,
NM. ERMS 555494.
U.S. Department of Energy (DOE) 2011b. Inputs and Information for the SDI Thermal Test Planned
Change Notice. U.S. Department of Energy Waste Isolation Pilot Plant, Carlsbad Area Office,
Carlsbad, NM. ERMS 555495.
C. Stone, J. Holland, J. Bean, and J. Arguello 2010. Coupled thermal-mechanical analyses of a generic
salt repository for high level waste. In 44th US Rock Mechanics Symposium and 5th US-
Canadian Rock Mechanics Symposium, Salt Lake City, UT, June 2010. American Rock
Mechanics Association.
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5.0 Python Script Listing
The Python script used to compute the solution and plot the figures in this report is listed below for
completeness,
# this script is part of tlie SIVL SDI proposal scoping work
# by Krlatopbmr £, Kunlmda, Repository p&xiQxmamem sept, t62121
la^ort jrasyy mm np f array function<*lity
team maipy.apmciml Ingorfc expl # exponent*ial integral
IffV Mtplotlib.pyplot pit # plot ting- functional! hy
d«C G(al,fl,tl,rl) s
*""ZD solution for line source
al = eternal diffuaivity ftr/far*JTJJ
tl = ZD time vector fa J
rl - radial distance (any shape >= ID) [bi]
*\ tt ii
oldahape = list(rl.shape)
nt * tl.shape [.1]
r 1.shape = (1,-1) # reform into ID vector with sijaijletan second dim
til.Shape - (-1,1) § make I: conformable with r
zi - fi/(4.0*i*p.pi*al)*ejcpl(rl**2/(4.0*al*tl>)
# change Mrft to original shape
rl.shape = oldahape
tl.shape = (nt,)
# reshape result so , (intensions like r
# with the t dimensit 1 in front
oldahape.insert(0,nt)
zi.shape = ol&shape
xmtmrm. ZI
def H
# sink {only positive times air t'alidj
Tl = G (»2, f 2, tt [mu : ] , r2)
# caeSoiam #ourc# and sink
T2 - np.empty_like(T0)
T2 [ ;nnz] = TO [ :tms] # before fieater turns o£t~
*2(nasi) « TO bast] - Til si # after bmker turns off
ruturn T2
def beaters(a3,f3,t3,tau3,xg,yg,htrs)i
""" use superposition to in horizontal lx. y) to sum up
effects of multiple heaters installed at different x,y locations,
assuming- all Beaters are at tie same elevation.
-------
AP-156 SDI Thermal Analysis Report
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a4,k4,t4 are same as Gf)
tau4,(4 are same as HI)
xg,yg are arrays of observation coordinates (ml
source terms are located at complex coordinates passed
in the list btrs (heaters) [m] .
ft If W
Wah»pt > list(xg.shape)
Hahap«.insert(0,t3.shape[0])
W3 = np.zerosfWshape,dtype-np.float64)
Zg = xg + yg*lj
for 1, heat In enumerate(htro):
ft compute relative horizontal 12DJ distance from heater
rg = np,abs(Zg - heat)
W3 +- H!*3, £3,t3,tau3,eg)
return W3
$ & l?^"1 vfy C3 ^ @ S' i2l@@© @>@ < iKi-fai I'i1 £0faKa) (a/ ;i f E^u)@{5i \ 'W?j| (d> (ij [aKj"i (jy (?y IfiKff @
# setup material properties
k = 5.4 # thermal conductivity [Watt/ (meter*Kel vin))
alfa = 2.648E-6 ft thermal diffusivity [meter" 2/second)
density « 2150,0 # density of salt ikg/w'3]
Cp = 931.0 # heat capacity of salt [Joule/ (kilogram*Kelvin) J
strength = 8500,0 # p^wer of each heater fWatt.J
fo = strength/(Cp*density*16.67) # line source strength
# setup calculation grid and input parameters
aeeperyr = 365.2422*24.0*60.0*60,0 # seconds in a year
tf time after t•-u heatern get turned off [2 years in seconds]
tau = 2.0 *saqperyr # end of hea ters
maxt = 20.0 *Becperyr # "final" map calculation date (2035, assuming begins in 2015)
# Computetionai grid is with respect to SL>1
# proposal figure !north is to left), so computational
# ,\f is South fx- is North), y+ is East (y- is West)
# cotupute out to 75Om since it is about 680 m
# from proposed heater locations (as per SDI proposal) to panel 1
nt,nx,ny = (22,100,100)
minx,miny = (-100.0, -750.0)
maxx.maxy - (750,0, 100.0)
tg • np.lin»pace{l,0E-6,maxt,nt) if time fseconds]
# compute on a grid, with center of heater array at origan.
xg,yg = np.meshgrlcKnp.llnspacetminy.maxy.iiy) (np,linopace(rainx,niaxx,rix))
ft ID mesh for plotting
X,Y = np.tngrid[minx:inaxx:nx*l;|, rainy:maxy:ny*ljl
t) perform calculation
# distances related to proposed geometry of heaters
ft estimated from figures in SDI proposal
hdew =15.5 If east-west distance between heaters
hdne = 20.0/2.0 ft half north-south distance between heaters
htre = thdns - hdew/2.0*1j,
hone + hdev/2.0*lj,
-hdns -hdew*lj,
-hdjia + Qj,
-hdna + hdew*lj]
-------
AP-156 SDI Thermal Analysis Report
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if == " Main. 11:
# compute* solution on a JD grid fro* M8139 to MB138
# r i»s dimensions : (nt,nx,ny,nxl
T » heatera{alfa,£o,tg,tan,xg,yg,htra)
# log plotting doesn't like zeros (underflow of calculation above}
# but seems to be ok with NaNs
T[T—C] = np.iiaH
ncnt = 19 # numb&i of contours
cntmin - -16. 0 # min/max contour range
CiltlMkX = 2,0
# «^#g«a«!Wittiaoet«e»6»ewew
# plot figures of results
Ftint 'x,Y,t,T ,xg.shape,yg,shape»fcg.shape,T.shape
print 'min, max* ,np.iraumin[T! ,np.raaiwax(T)
# plot logT contours of ijeat at 203S
fig = pit. figured)
ax » fig.add_mibplot (ill)
EP « ax.contourf(X[i, i J ,Y[i, si . rrp. loglO (T [-1, :,:)),
levelu-np.linapace(eatnin,cntroax,ncnt))
pe = &x.contour (X[i, :] ,¥[:» i] ,np.lDglO(T[-l, :,¦]),
levelB>np. linapace (cntmin, cntraax, ncnt),colon-'black', linawidth-0,SI
eb = fig.colorbar(pp)
cSs, set_labBl {1 $\\log JlO J IT) 5 rise [K] ')
ax.a«tjxlabel {'X [to] ' S
ax,eet_ylabel{'Y [¦]')
for h in htrs:
ax.plot(h.inag,h.r«al,' k*')
pit.axis{•image')
pit. grid ()
«x.wt_tltla( 'top riaa contours at top ot waste panel level')
pit. aavefig (' and logtwap coat ours - at-panel-leve 1. png1, transparent-Time)
pit.close(1!
# compute solution for radial profile ac different- times
xg - np.linapace(0,7 00, 50 0)
yg = up.leroalikefxg)
mint =0,1
naxt = 100000.0
tg - np.array!(2.20,70,200,2000])*secperyr
T - heaters{alfa,fo,tg,tau,xg,yg,htrs)
fig = pit.figure(1)
ax = tig.addaubplot{111)
tor i,tval in rnunexate(tg):
ax.Bejnilogy(xg,T[i, s] ,lab«l¦»'%.<>f yrs1 % (tval/secperyr,))
ax.«Bt_ylii#( ll.OS-7,100J)
ax.Mt xlabel (' dUatanc* from center of SDI area [m] ')
ax.set_ylabel('temperatare rise [K]1)
pit.grid()
ax. »at_title (' te*p profile at different: tiroes')
pit.legend(loc»1upper right")
pit.savefig('temp-proflie.png')
pit., closed)
# compute solution a t log- spacing of tiw€
xg - up.array)[10.0,40.0,100.0,200,0,400,0,700.0])
yg « np.zeroH_like(xg)
mint = 0.1
naxt = 100000.0
tg * up. logspace(np.loglO (mint*aecperyr) ,ap.loglO (inaxt*afecperyr))
T = heaters(alfa.£0,tg,tau,xg,yg,htra)
M plot temperature through time 50, 100, 200, 4 00, arid 700 m east of heaters
-------
fig = pit.figure(1)
ax = fig -add_subplot(111)
for i,xval in enumerate(xg):
print i,xval
ax. loglog(tg/eecperyr,T{:, i] , label= n. 0 f m % xval)
ax.set_xlabel('time since heaters turned on [yrs!')
ax.set_ylabel(1 temperature rise (K)•)
ax.set_ylim[{1.QE-7,100.03)
ax.setxlim[ [mint.maxt])
pit .grid!)
pit.legend(loc=¦lower right')
plt.aavefig{' temperaturs-through- time . png')
plt.cloae(l)
AP-156 SDI Thermal Analysis Report
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-------
Kuhlman, Kristopher L
From:
Pasch, James Jay
Wednesday, May 25, 2011 2:12 PM
Kuhlman, Kristopher L
Lee, Moo
signature authority
Sent:
To:
Cc:
Subject:
I, James Pasch, give signature authority to Kris Kuhlman for the following document.
Analysis Report
AP-156 Revision 0
SDI Heater Testing Long-Term Thermal Effects Calculation
(AP-156: Analysis Plan for the Impact Determination of SDI Heater Testing on Long-Term WIPP
Performance)
-------
Enclosure 5
-------
SANDIA NATIONAL LABORATORIES
WASTE ISOLATION PILOT PLANT
Impact Assessment of SDI Excavation on Long-Term WIPP
Performance
Revision 0
Author:
Author.
Author:
Author:
Author:
R, Chris Camphouse
Print
Dwavne C, Kicker
Print
Thomas B. Kirchner
"7//v/2^ / /
Signature / Date
C_p> ifmfzon
Date
7i
Signature
¦zyrZ-f*
0
Date
2Jb\\
Technical
Review:
QA
Review
Management
Review:
Print
Moo Lee
Print
Signature
T7
Signature
Date
Date
WIPP:1.4.1.2:PA:QA-L:555562
-------
Impact Assessment of SDI Excavation on Long-Term W1PP Performance
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Table of Contents
Executive Summary 6
1 introduction 7
2 SDI Excavation 8
3 FEPS Re-assessment 10
4 Methodology 10
5 Run Control 12
6 Results 12
6.1 Salado Flow Results 13
6.2 Spallings 26
6.3 Direct Brine Releases 29
6.4 Total Normalized Releases 34
7 Summary 39
8 References 40
APPENDIX A SDI Code Execution 42
A.l Salado Flow Calculations (BRAGFLO) 43
A.l.l Salado Flow Step 1 43
A.1.2 Salado Flow Step 2 44
A.l .3 Salado Flow Step 3 45
A.l .4 Salado Flow Step 4 45
A.l.5 Salado Flow Step 5 46
A. 1.5.1 General Case 46
A. 1.5.2 Modified BRAGFLO Input Case 47
A.2 Single-Intrusion Solids Volume Calculations (CUTTINGS_S) 48
A.2.1 Solids Volume Step 1 49
A.2.2 Solids Volume Step 2 49
A.2.3 Solids Volume Step 3 50
A.3 Single-Intrusion Direct Brine Release Calculations (BRAGFLO) 51
A.3.1 Direct Brine Release Step 1 52
A.3.2 Direct Brine Release Step 2 ..52
A.3.3 Direct Brine Release Step 3 54
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A.4 CCDF Input Tabulations (SUMMARIZE) 56
A.4.1 CCDF Input Tabulation for Direct Brine Release..... ...........56
A.5 CCDF Construction (PRECCDFGF, CCDFGF) 57
A.5.1 CCDF Construction Step 1 58
A,5,2 CCDF Construction Step 2 58
A.5.3 CCDF Construction Step 3 59
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Impact Assessment of SDI Excavation on Long-Term WIPP Performance
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List of Figures
Figure 2- /: SDI Excavation Schematic 9
Figure 6-1: PABC-2009 BRAGFLO grid (Ax, Ay, andAz dimensions in meters) 14
Figure 6-2: SDI BRAGFLO grid changes (Ax, Ay, andAz dimensions in meters) 15
Figure 6-3: Overall Means of Volume Averaged Pressure for the Experimental Region, Scenario Sl-BF. 18
Figure 6-4: Overall Means of Volume Averaged Pressure for the Experimental Region, Scenario S2-BF. 19
Figure 6-5: Overall Means of Volume Averaged Pressure for the Experimental Region, Scenario S4-BF. 19
Figure 6-6: Overall Means of Volume Averaged Pressure for the Experimental Region, Scenario S6-BF. ...20
Figure 6-7: Overall Means of Volume Averaged Pressure for the Waste Panel, Scenario Sl-BF, 20
Figure 6-8: Overall Means of Volume Averaged Pressure for the Waste Panel, Scenario S2-BF. 21
Figure 6-9: Overall Means of Volume Averaged Pressure for the Waste Panel, Scenario S4-BF. 21
Figure 6-10: Overall Means of Volume Averaged Pressure for the Waste Panel, Scenario S6-BF. 22
Figure 6-11: Overall Means of Total Brine Flow Into the Waste Panel, Scenario Sl-BF 22
Figure 6-12: Overall Means of Total Brine Flow Into the Waste Panel, Scenario S2-BF 23
Figure 6-13: Overall Means of Total Brine Flow Into the Waste Panel, Scenario S4-BF 23
Figure 6-14: Overall Means of Total Brine Flow Into the Waste Panel, Scenario S6-BF 24
Figure 6-15: Overall Means of Brine Saturation in the Waste Panel, Scenario Sl-BF 24
Figure 6-16: Overall Means of Brine Saturation in the Waste Panel, Scenario S2-BF 25
Figure 6-17: Overall Means of Brine Saturation in the Waste Panel, Scenario S4-BF 25
Figure 6-18: Overall Means of Brine Saturation in the Waste Panel, Scenario S6-BF 26
Figure 6-19: SDI and PABC-2009 Overall Mean CCDFs for Normalized Spallings Releases 29
Figure 6-20: SDI and PABC-2009 DBR material map (logical grid) 30
Figure 6-21: All replicates for SDI scenario S2-DBR lower intrusions 32
Figure 6-22, All replicates for PABC 2009 scenario S2-DBR lower intrusions .....32
Figure 6-23: SDI DBR Volume vs. Pressure, Scenario S2-DBR, Replicate I, Lower Intrusion 33
Figure 6-24: SDI and PABC-2009 Overall Mean CCDFs for Normalized Direct Brim Releases 34
Figure 6-25: SDI Replicate 1 Total Normalized Releases 36
Figure 6-26: SDI Replicate 2 Total Normalized Releases 36
Figure 6-27: SDI Replicate 3 Total Normalized Releases 37
Figure 6-28: SDI Mean and Quantile CCDFs for Total Normalized Releases, Replicates 1-3 ,,,37
Figure 6-29: SDI Confidence Limits on Overall Mem for Total Normalized Releases 38
Figure 6-30: SDI and PABC-2009 Overall Mean CCDFs for Total Normalized Releases 38
Figure 6-31: SDI Primary Components Contributing to Total Releases 39
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List of Tables
Table I: BRAG FLO Modeling Scenarios - 16
Table 2: BRAGFLO SDl Summary Statistics 17
Table 3: PA Intrusion Scenarios Used in Calculating Direct Solids Releases 27
Table 4; Summary of Spallings Releases by Scenario 28
Table 5: PABC-2009 and SDl PA DBR Volume Statistics 31
Table 6: SDl PA and PABC-2009 Statistics on the Overall Mean for Total Normalized Releases in EPA Units at
Probabilities of 0.1 and0.001 35
Table 7; WIPP PA Alpha Cluster Nodes Used in SDl Calculations 42
Table 8: WIPP PA VMS Software Used in the SDl Calculations 42
Table 9; Salado Flow Run Control Scripts 43
Table 10: Salado Flow Step 1 Input and Output Files 44
Table 11; Salado Flow Step 2 Input and Output Files 44
Table 12: Salado Flow Step 3 Input and Output Files 45
Table 13: Salado Flow Step 4 Input and Output Files 46
Table 14: Salado Flow Step 5 Input and Output Files (Generic Case) 47
Table 15: Salado Flow Step 5 Modified Input Runs 48
Table 16: Salado Flow Step 5 Modified Input Runs File Names 48
Table 17: Solids Volume (CUTTINGSJS) Run Control Scripts 49
Table 18: Solids Volume Step / Input and Output Files 49
Table 19: Solids Volume Step 2 Input and Output Files 50
Table 20: Solids Volume Step 3 Input and Output Files 51
Table 21: Direct Brine Release Rim Control Scripts 51
Table 22: Direct Brine Release Step 1 Input and Output Files 52
Table 23: Direct Brine Release Step 2 Input and Output Files 53
Table 24: Direct Brine Release Step 3 Input and Output Files 55
Table 25: CCDF Input Tabulation Run Control Scripts 56'
Table 26: CCDF Input Tabulation Input and Output Files (Direct Brine Release) 57
Table 27: CCDF Construction Run Control Scripts 57
Table 28: CCDF Construction Step 1 Input and Output Files 58
Table 29: CCDF Construction Step 2 Input and Output Files 59
Table 30: CCDF Construction Step 3 Input and Output Files 60
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[mpact Assessment of SDI Excavation on Long-Term WIPP Performance
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EXECUTIVE SUMMARY
With the recertification of the WIPP in November of 2010 (U.S. EPA 2010), a new PA baseline
was established by the 2009 Performance Assessment Baseline Calculation (PABC-2009).
Following this most recent recertification decision, the DOE plans to submit a planned change
notice to the EPA that justifies additional excavation in the WIPP experimental area. This
excavation will be done in order to support salt disposal investigations (SDI) that include field-
scale heater tests at WIPP. This report summarizes the impact of the additional SDI excavation
on long-term repository performance with particular emphasis on spallings and direct brine
releases, two of the dominant release mechanisms.
Total normalized releases calculated in the SDI impact assessment remain below their regulatory
limits. As a result, the additional excavation in the WIPP experimental area to support SDI
would not result in WIPP non-compliance with the containment requirements of 40 CFR Part
191. Cuttings and cavings releases and direct brine releases are the two primary release
components contributing to total releases in the SDI calculations. Cuttings and cavings releases
are unchanged from those calculated in the PABC-2009. Additional excavation for SDI results
in small impacts to pressures and brine saturations in repository waste-containing regions, but
these changes collectively result in a negligible difference between direct brine releases seen in
the SDI impact assessment and the PABC-2009. Small reductions are observed in SDI spallings
releases as compared to the PABC-2009, but these differences are relatively minor and do not
have a significant impact on the overall total normalized releases found in the SDI impact
assessment. As a result, total normalized releases found in the SDI calculations and the PABC-
2009 are indistinguishable.
An additional component of the overall SDI analysis performed is a determination of the impact
that planned heater tests have on the state of the repository at the time of closure. That analysis
demonstrated that the impact of heater testing on the temperature of WIPP waste-containing
areas is negligible. Results from the SDI thermal analysis are presented in a separate report
(Kuhlman 2011).
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Impact Assessment of SD1 Excavation on Long-Term WIPP Performance
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1 INTRODUCTION
The Waste Isolation Pilot Plant (WIPP), located in southeastern New Mexico, has been
developed by the U.S. Department of Energy (DOE) for the geologic (deep underground)
disposal of transuranic (TRU) waste. Containment of TRU waste at the WIPP is regulated by the
U.S. Environmental Protection Agency (EPA) according to the regulations set forth in Title 40 of
the Code of Federal Regulations (CFR), Part 191. The DOE demonstrates compliance with the
containment requirements according to the Certification Criteria in Title 40 CFR Part 194 by
means of performance assessment (PA) calculations performed by Sandia National Laboratories
(SNL). WIPP PA calculations estimate the probability and consequence of potential
radionuclide releases from the repository to the accessible environment for a regulatory period of
10,000 years after facility closure. The models are maintained and updated with new
information as part of a recertification process that occurs at five-year intervals following the
receipt of the first waste shipment at the site in 1999.
With the recertification of the WIPP in November of 2010 (U.S. EPA 2010), a new PA baseline
was established by the 2009 Performance Assessment Baseline Calculation (PABC-2009).
Following this most recent recertification decision, the DOE plans to submit a planned change
notice (PCN) to the EPA that justifies additional excavation in the WIPP experimental area. This
excavation will be done in order to support salt disposal investigations (SDI) that include field-
scale heater tests at WIPP.
The proposed expansion of the WIPP experimental area in order to facilitate SDI work requires
an assessment of associated impacts on long-term repository performance. The impacts of
additional volume on pressure and brine saturation in and around the waste regions of the
repository must be determined as these quantities potentially impact release mechanisms such as
spallings and direct brine releases (DBRs). The DOE has requested that SNL undertake
calculations and analyses to determine the impacts of additional repository volume on the long-
term performance of the facility (U.S. DOE 2011 a, 201 lb). The impacts of additional excavated
volume are determined by a comparison to results obtained in the PABC-2009. This report
provides a summary of calculations and analyses used to determine the impact of additional
excavated volume in the WIPP experimental area on regulatory compliance.
An additional component of the overall SDI analysis performed is a determination of the impact
that planned heater tests have on the state of the repository at the time of closure. That analysis
demonstrated that the impact of heater testing on the temperature of WIPP waste-containing
areas is negligible. Results from the SDI thermal analysis are presented in a separate report
(Kuhlman 2011).
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Impact Assessment of SDI Excavation on Long-Term WIPP Performance
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The work undertaken in the SDI impact assessment is prescribed in AP-156, Analysis Plan for
the Impact Determination of SDI Heater Testing and Associated Excavation on Long-Term
WIPP Performance (Camphouse and Kuhlman 2011). In order to isolate the impacts of
additional experimental volume on regulatory compliance, the SDI impact assessment was
designed to deviate as little as possible from the PABC-2009 implementation. In particular, the
SDI investigation utilizes the same waste inventory information, drilling rate and plugging
pattern parameters, and radionuclide solubility parameters as were used in the PABC-2009. The
SDI impact assessment is essentially a focused re-run of the PABC-2009 calculation using a
slightly modified numerical grid in the Salado flow calculation that accounts for additional
volume in the repository experimental area,
2 SDI EXCAVATION
A schematic depicting the additional SDI excavation to the repository experimental area is
included in U.S. DOE (2011b), and is shown in Figure 2-1 for convenience. From that figure,
the additional volume added to the experimental area can be calculated.
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Impact Assessment of SDI Excavation on Long-Term WTPP Performance
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drifts' 8 833 f«i ffi 16' wkte by f J' M;l" *36 049 to"«
Figure 2-1: SDI Excavation Schematic
As seen in Figure 2-1, the volume of the SDI access drifts is (9,633 ft) x (16 ft) x (13 ft) =
2,003,664 ft3. Moreover, from that figure, the tonnage of excavated salt corresponding to this
volume is 136,049 tons. These quantities provide a conversion factor of tonnage to excavated
volume of 1 excavated ton = 14,73 ft3, The total mined tonnage associated with the SDI
excavation is listed in Figure 2-1 as 144,650 tons because of some additional volume associated
with the heater test area and alcoves. Using the conversion factor obtained above, the total
volume corresponding to the additional SDI excavation is 2,130,694.5 ft3, or 60,335 m3 (after
rounding). The SDI impact assessment includes this additional volume of 60,335 m in the
experimental sub-region of the numerical grid used for Sal ado flow modeling. Aside from this
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Impact Assessment of SDI Excavation on Long-Term WIPP Performance
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change to the Salado numerical grid, the parameters and sampled distribution values used in the
SDI impact assessment are identical to those implemented in the PABC-2009.
3 FEPS RE-ASSESSMENT
Ail assessment of the FEPs baseline was conducted to determine if the current FEPs basis
remains valid in consideration of changes introduced by the proposed SDI experimental
program, and was performed according to SP 9-4, Performing FEPs Impact Assessment for
Planned or Unplanned Changes. The FEPs analysis concludes that no additional FEPs are
needed to accurately represent the changes to the repository layout resulting from additional
excavation in the WIPP experimental area. Additionally, no FEPs screening arguments and
associated screening decisions require modification to account for these changes (Kirkes 2011),
4 METHODOLOGY
The performance assessment methodology accommodates both aleatory (i.e. stochastic) and
epistemic (i.e. subjective) uncertainty in its constituent models. Aleatory uncertainty pertains to
unknowable future events such as intrusion times and locations that may a fleet repository
performance. It is accounted for by the generation of random sequences of future events.
Epistemic uncertainty concerns parameter values that are assumed to be constants, but the exact
parameter values are uncertain due to a lack of knowledge about the system. An example of a
parameter with epistemic uncertainty is the permeability of a material, Epistemic uncertainty is
accounted for by sampling of parameter values from assigned distributions. One set of sampled
values required to run a WIPP PA calculation is termed a vector. In the SDI impact assessment,
models were executed for three replicates of 100 vectors, each vector providing model
realizations resulting from a particular set of parameter values. Parameter values sampled in the
PABC-2009 were also used in the SDI impact assessment, and are documented in Kirchner
(2009). A sample size of 10,000 possible sequences of future events is used in PA calculations
to address aleatory uncertainty. The releases for each of 10,000 possible sequences of future
events are tabulated for each of the 300 vectors, totaling 3,000,000 possible futures.
For a random variable, the complementary cumulative distribution function (CCDF) provides the
probability of the variable being greater than a particular value. By regulation, performance
assessment results are presented as a distribution of CCDFs of releases (U.S. EPA 1996). Each
individual CCDF summarizes the likelihood of releases across all futures for one vector of
parameter values. The uncertainty in parameter values results in a distribution of CCDFs.
Releases are quantified in terms of "EPA units". Each radionuclide has a release limit prescribed
to it. This limit is defined as the maximum allowable release (in curies) of that radionuclide per
a waste amount containing lxl06 curies of alpha-emitting transuranic radionuclides with half-
lives greater than 20 years. Releases in EPA units result from a normalization by radionuclide
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Impact Assessment of SDI Excavation on Long-Term WIPP Performance
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and the total inventory. For each radionuclide, the ratio of its 10,000 year cumulative release (in
curies) to its release limit is calculated. The sum of these ratios is calculated across the set of
radionuclides and normalized by the transuranic inventory (in curies) of a-emitters with half-
lives greater than 20 years, as specified by regulation. Mathematically, the formula used to
calculate releases in terms of EPA units is of the form
where R is the normalized release in EPA units. Quantity Qj is the 10,000 year cumulative
release (in curies) of radionuclide i. Quantity L, is the release limit for radionuclide if and C is
the total transuranic inventory (in curies) of a-emitters with half-lives greater than 20 years.
Note that the definition of the release limit Lt results in a constant value of 1 x 10e curies being
factored out of the summation.
The SDI impact assessment was developed so that the structure of calculations performed therein
was as similar as possible to that used in the PABC-2G09. PABC-2009 calculated results
impacted by additional excavated volume in the WIPP experimental area were updated, while the
results from previous PAs were used for individual numerical codes not affected by these
changes. The SDI impact assessment utilized the same waste inventory information, drilling rate
and plugging pattern parameters, and radionuclide solubility parameters as were used in the
PABC-2009.
Additional volume in the WIPP experimental area conceivably results in a pressure reduction in
that region. Lower pressure in the experimental area in combination with the long WIPP
regulatory time period of 10,000 years potentially results in an eventual reduction in pressure in
WIPP waste-containing areas. Pressure changes in the waste panels translate directly to changes
in spallings releases as reductions in pressure yield reductions in spallings volumes. Moreover,
pressure reductions in waste areas potentially allow a larger influx of brine into these regions,
corresponding to increases in brine saturation. Direct brine releases are a function of pressure
and brine saturation at the time of intrusion. Two conditions must be met for a DBR to occur.
First, the brine saturation in the intruded panel must exceed the residual brine saturation of the
waste, a sampled parameter in PA. Second, the repository pressure near the drilling location
must exceed the hydrostatic pressure of the drilling fluid, which is specified in PA to be 8 MPa.
The combined impact of lower pressure and increased brine saturation on DBRs is nontrivial. A
pressure reduction would be expected to result in a corresponding reduction in the number of
vectors that satisfy the DBR pressure requirement. Increases in brine saturation would be
expected to result in an increase in the number of vectors that satisfy the DBR brine saturation
requirement. As a result, it is not apparent if the net impact of lower pressure and increased
brine saturation results in more or fewer vectors overall that satisfy both DBR requirements. For
these reasons, spallings and direct brine releases are the primary release mechanisms of interest
R =
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in the SDI impact assessment. Additional volume in the experimental region has no impact on
releases due to cuttings and cavings. Transport releases through the Culebra had virtually no
impact on total normalized releases in the PABC-2009 (Clayton et al 2010). Additional volume
in the repository experimental area will not change this result. Consequently, transport releases
through the Culebra calculated in the PABC-2009 are also used in the SDI impact assessment.
5 RUN CONTROL
Run control documentation of codes executed in the SDI impact assessment is provided in
APPENDIX A. This documentation contains:
1. A description of the hardware platform and operating system used to perform the
calculations.
2. A listing of the codes and versions used to perform the calculations.
3. A listing of the scripts used to run each calculation,
4. A listing of the input and output files for each calculation.
5. A listing of the library and class where each file is stored.
6. File naming conventions.
As described previously. PABC-2009 results were used for individual numerical codes primarily
unaffected by SDI excavation in the WIPP experimental area. Documentation of run control for
results calculated in the PABC-2009 is provided in Long (2010).
6 RESULTS
Additional excavated volume in the WIPP experimental region has no impact on cuttings and
cavings releases resulting from drilling intrusions in repository waste areas. Cuttings and
cavings results obtained in the SDI impact assessment are identical to those found in the PABC-
2009. In addition Culebra transport results calculated in the PABC-2009 were used in the SDI
calculations. Discussions of cuttings and cavings releases, as well as Culebra transport releases,
calculated in the PABC-2009 can be found in Clayton et al (2010) and the references therein,
'lire primary focus of the SDI impact assessment is a determination of pressure and brine
saturation changes in waste-containing repository regions, and the impacts these changes have on
spellings releases and DBRs. Spallings releases and DBRs are two of the release components
used to calculate total normalized releases. As a result, the impact of pressure and brine
saturation changes on total normalized releases is of interest as well.
Summary results obtained from the SDI impact assessment are broken out in sections below, and
are compared to PABC-2009 results. Salado flow modeling results are presented in Section 6.1.
Spallings results are presented in Section 6.2. Direct brine releases are presented in Section 6.3.
The impact of proposed SDI excavation on regulatory compliance is discussed in terms of total
normalized releases in Section 6.4. Files used to generate plots and summary statistics in the
results that follow are included on a CD submitted with this report. As the CCDF is the
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regulatory metric used to demonstrate compliance, CCDFs obtained in the SDI impact
assessment and the PABC-2009 are compared for each component of release in the appropriate
section.
6,1 Salado Flow Results
The BRAGFLO software calculates the flow of brine and gas in the vicinity of the WIPP
repository over the 10,000-vear regulatory compliance period. The computational grid used in
the PABC-2009 BRAGFLO calculations is shown in Figure 6-1, where the WIPP experimental area
is denoted by region "Exp". As seen in that figure, the volume of the experimental region
implemented in the PABC-2009 discretization is
2( (30.61m) x (361.65m) x (1.32m + 1.32m + 1.32m)) = 87,675 rn3.
As developed in Section 2, the volume resulting from additional excavation in the experimental
region for SDI is 60,335 m3. As a result, the target volume of the experimental region
implemented in the SDI BRAGFLO computational grid is 87,675 m3 + 60,335 rrr = 148,010 m3.
To achieve this value, the experimental region of the BRAGFLO grid implemented in the SDI
impact assessment was modified from that used in the PABC-2009. Elements corresponding to
the experimental area were lengthened in the z-direction for the SDI impact assessment. Two
elements lengths of 30.61 meters in the /.-direction were used in the PABC-2009. For the SDI
calculations, these two lengths were increased to 51.67 meters and 51.68 meters. The resulting
t i Ti
volume of the experimental region in the SDI BRAGFLO numerical grid is 148,011 rn , one
cubic meter greater than the target value. Changes in clement sizes comprising the experimental
region from the PABC-2009 to the SDI impact assessment are summarized in Figure 6-2. No
other changes were made to the PABC-2009 BRAGFLO grid for the SDI impact assessment.
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Row
Ax
S'S'g S S 2S
n rj r- iH ai S ^ rsj fsi
U> «>
TSH? ^ Its ™ £ Snsg ssfssss 8 8 8S™§S $ e'8 8S*gS
2f?SESBRSS?!^SS8?SSi-,CE,,'t,'"3Srs'Ritv255?,-§SS,~S
* % t < o 1-1 m -i- _? *- +- w-
>4 M ni -¦— — O
*-* tj « w m uni-»i-rtDt«3,rp>n®ool'1o ~co'o;2QgD'C5QQf3Q}(5in«-'-*"333^wqa5®maj«pfvOir S 2 ^ S I S
¦¦— T' -4= oa*- S r- n id p ^ c» ip r3 iO r-* rt «jr 1J t- |/ r« y P $ ij ^ w ^ v "U* *"" *"" v w w w »¦ o <71 r» « ^ C »— t
X (ixxlh)
Figure 6-1: PABC-2009 BRAG FLO grid (Ax, Ay, and Az dimensions in meters)
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PABC-2009 Experimental Grid
87,575 m3
Ay
1.32
1.32
1.32
AY
1.32
1.32
1.32
SDI Experimental Grid
148,011 ms
AX 361.S5 361.65 Ax 361.65 361.65
Az 30.61 30.61 Ai 51.67 51.68
Figure 6-2: SDI BHAGFLO grid changes (Ax, Ay, and Az dimensions in meters).
During BRAGFLO calculations, stochastic uncertainty is addressed by defining a set of six
scenarios for which brine and gas flow is calculated for each of the vectors generated via
parameter sampling. The total number of BRAGFLO simulations executed in the SDI impact
assessment is 1,800 (300 vectors times 6 scenarios).
The six scenarios used in the SDI impact assessment are unchanged from those used for the
PABC-2009. The scenarios include one undisturbed scenario (Sl-BF), four scenarios that
include a single inadvertent future drilling intrusion into the repository during the 10,000 year
regulator)' period (S2-BF to S5-BF), and one scenario investigating the effect of two intrusions
into a single waste panel (S6-BF). Two types of intrusions, denoted as HI and E2, are
considered. An El intrusion assumes the borehole passes through a waste-filled panel and into a
pressurized brine pocket that may exist under the repository in the Castile formation. An E2
intrusion assumes that the borehole passes through the repository but does not encounter a brine
pocket. Scenarios S2-BF and S3-BF model the effect of an El intrusion occurring at 350 years
and 1000 years, respectively, after the repository is closed. Scenarios S4-BF and S5-BF model
the effect of an E2 intrusion at 350 and 1000 years. Scenario S6-BF models an E2 intrusion
occurring at 1000 years, followed by an El intrusion into the same panel at 2000 years.
Transport releases to the Culebra arc captured in Scenario S6-BF. Transport releases from the
Culebra obtained in the PABC-2009 are also used in the SDI impact assessment. However,
results from BRAGFLO scenario S6-BF arc briefly discussed in this report for the sake of
completeness. In the Salado flow results that follow, summary statistics and plots were
generated with Matlab, a commercial off-the-shelf software package. Matlab files used in the
SDI impact assessment are included on a cd submitted with this summary report. BRAGFLO
scenarios considered in the SDI impact assessment are summarized in Table 1.
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Table 1: BRAG FLO Modeling Scenarios
Scenario
Description
S1-BF
Undisturbed Repository
S2-BF
E1 intrusion at 350 years
S3-BF
E1 intrusion at 1,000 years
S4-BF
E2 intrusion at 350 years
S5-BF
E2 intrusion at 1,000 years
S6-BF
E2 intrusion at 1,000 years: E1 intrusion at 2,000 years.
BRAGFLO results arc presented for the SDI impact assessment and compared with those
obtained in the PABC-2009. Results are discussed in terms of overall means. Overall means are
obtained by forming the average of the 300 realizations calculated for a given quantity and
scenario. Results are presented for undisturbed scenario Sl-BF. Results associated with
intrusions are presented for scenarios S2-BF and S4-BF, as these are representative of the
intrusion types considered in scenarios S2-BF to S5-BF with the only differences being the
timing of dri lling intrusions. Results from BRAGFLO scenario S6-BF are also discussed.
The overall means of pressure in the experimental area, denoted by quantity EXP PRES, are
shown in Figure 6-3 for undisturbed scenario Sl-BF, and Figure 6-4, Figure 6-5, Figure 6-6 for
intrusion scenarios S2-BF, S4-BF, and S6-BF, respectively. As seen in those figures, the
additional volume in the SDI calculations results in a reduction in the average pressure in the
experimental area for all scenarios when compared to PABC-2009 results.
Reduced pressure in the experimental area combined with the long WIPP regulatory period of
10,000 years results in eventual lower average pressure in the waste panel as compared to
PABC-2009 results. The reduction in average waste panel pressure, denoted by quantity
WAS PRES, for undisturbed scenario Sl-BF is illustrated in Figure 6-7. Eventual pressure
reductions in the waste panel are also seen for El intrusion scenarios (Figure 6-8), E2 intrusion
scenarios (Figure 6-9), and the E2E1 intrusion scenario (Figure 6-10).
A probable consequence of lower average pressure in the waste panel is a corresponding
increase in the average cumulative flow of brine into die panel, denoted by quantity
BRNWASIC. As seen in Figure 6-11 through Figure 6-14, the reduction in average pressure in
the waste panel does indeed yield slight increases in the total amount of brine entering the panel
for both undisturbed and disturbed conditions. These slight increases of brine flow into the panel
result in slight increases in the average panel brine saturation, denoted by quantity WAS SATB.
As seen for the undisturbed case shown in Figure 6-15 and the intrusion scenario results shown
in Figure 6-16 through Figure 6-18, the average brine saturation in the waste panel is slightly
increased for all scenarios considered in the SDI impact assessment as compared to the PABC-
2009.
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Summary statistics for the SDI BRAGFLO results discussed above are shown in Table 2. In that
table, mean and maximum values for a given quantity are calculated over all 300 vectors. As the
brine saturation in the waste panel only varies between 0 and 1, values in Table 2 for thai
quantity are listed to three decimal places to make differences between analyses more apparent.
Table 2: BRAGFLO SDI Summary Statistics
Quantity
(units)
Scenario
Mean Value
Maximum Value
PABC-2009
SDI
PABC-2009
SDI
EXP PRES
(MPa)
SI-BP
4.46
4.04
15.65
15.15
S2-BF
4,41
4.04
14.77
14.62
S4-BF
3.70
3.36
14.70
14,56
S6-BF
4.18
3.81
14,76
14.63
WAS PRES
(MPa)
Sl-BF
6.52
6.34
16.19
16.18
S2-B.F
7.39
7.31
15.63
15.62
S4-BF
4.64
4.56
14.92
14.68
S6-BF
5.96
5.88
15.04
14.90
BRNWASIC
(x 103 m3)
Sl-BF
1.78
1.80
12.46
13.24
S2-BF
14.03
14.10
182.15
186.63
S4-BF
2.73
2.74
23.81
24.96
S6-BF
7.71
7.84
180.24
184,55
WAS SATB
(dimensionless)
Sl-BF
0.160
0.164
0.985
0.985
S2-BF
0.677
0.681
0,999
0.999
S4-BF
0.283
0.285
0.995
0.995
S6-BF
0.418
0.424
0.999
0,999
Using the BRAGFLO results presented above, the impact of SDI excavation on individual
components of release can now be initially discussed. Spallings release volumes are a function
of pressure. A reduction in waste panel pressure results in a corresponding reduction in spallings
release volumes. Therefore, one would expect that the additional SDI excavation results in a
slight decrease in spallings releases as compared to the PABC-2009 as both analyses use the
same waste inventory. Impacts on spallings releases are quantified in Section 6.2.
The impact of SDI excavation on DBRs is less straightforward. Sufficient pressure and brine
saturation in the panel at the time of intrusion are prerequisites for a DBR to occur. In particular,
brine saturation in the panel must exceed the residual brine saturation of the waste, a sampled
parameter in PA. In addition, the repository pressure near the drilling location must exceed the
hydrostatic pressure of the drilling fluid, which is observed at the repository elevation and
specified in PA to be 8 MPa. As seen in the SDI BRAGFLO results above, the average waste
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panel pressure was lowered in all scenarios as compared to the PABC-2009. Thus, one would
expect a corresponding reduction in the number of vectors that satisfy the pressure criteria for a
DBR. On the other hand, the average brine saturation in the waste panel increased for all
scenarios in the SDI calculation. From this, one would expect to see an increase in the number
of vectors that satisfy the DBR brine saturation requirement. As a result, the BRAGFLO results
shown above are not sufficient to detennine the impacts of SDI excavation on DBRs with
certainty. Additional analysis is required to quantify these impacts and is provided in Section
6.3.
10
9
8
7
^ A
Et
CO
c
DC 5
£L A
X 4
lu
3
2
1
0
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
Time (years)
Figure 6-3: Overall Means of Volume Averaged Pressure for the Experimental Region, Scenario Sl-BF.
CXeral S1-BF Means
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0
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
Time (years)
Figure 6-4: Overall Means of Volume Averaged Pressure for the Experimental Region, Scenario S2-BF,
0\erall S2-BF Means
0
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
Time (years)
Figure 6-5: Overall Means of Volume Averaged Pressure for the Experimental Region, Scenario S4-BF.
Overall S4-BF Means
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Overall S6-BF Means
Time (years)
Figure 6-6: Overall Means of Volume Averaged Pressure for the Experimental Region, Scenario S6-BF.
0
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
Time (years)
Figure 6-7: Overall Means of Volume Averaged Pressure for the Waste Panel, Scenario Sl-BF.
Overall S1-BF Means
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12
10
to
c0
Df 6
CL
I
W)
<
x 10
Overall S2-BF Means
0
_L L.
_l L_
SDI
PABC2009
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
"Time (years)
Figure 6-8: Overall Means of Volume Averaged Pressure for the Waste Panel, Scenario S2-BF.
x 10
Overall S4-BF Means
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
Time (years)
Figure 6-9: Overall Means of Volume Averaged Pressure for the Waste Panel, Scenario S4-BF.
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x 10
Overall S6-BF Means
v...
SDI
P ABC 2009
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
Time (years)
Figure 6-10: Overall Means of Volume Averaged Pressure for the Waste Panel, Scenario S6-BF.
Overall S1-BF Means
3000
2500
2000
cn~~~
£
O
<5 1500
s
CL
m
1000
500
_1 l_
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
Time (years)
Figure 6-11: Overall Means of Total Brine Flow Into the Waste Panel, Scenario S1-BF
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Impact Assessment ofSDf Excavation on Long-Term WIPP Performance
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x iq4 Overall S2-BF Means
Time (years)
Figure 6-12: Overall Means of Total Brine Flow Into the Waste Panel, Scenario S2-BF
Overall S4-BF Means
Time (years)
Figure 6-13: Overall Means of Total Brine Flow Into the Waste Panel, Scenario S4-BF
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Overall S6-BF Means
"Time (years)
Figure 6-14: Overall Means of Total Brine Flow Into the Waste Panel, Scenario S6-BF
Overall S1-BF Means
Time (years)
Figure 6-15: Overall Means of Brine Saturation in the Waste Panel, Scenario S1-BF
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Overall S2-BF Means
m
i-
<
in
1
0.9
0.8
0.7
0.6
0.5
w
5 0.4
0.3
0.2
0.
0
mL-
SDI
PABC2009
:/
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
Time (years)
Figure 6-16: Overall Means of Brine Saturation in the Waste Panel, Scenario S2-BF
0\erall S4-BF Means
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
Time (years)
Figure 6-17: Overall Means of Brine Saturation in the Waste Panel, Scenario S4-BF
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Owrall S6-BF Means
Time (years)
Figure 6-18: Overall Means of Brine Saturation in the Waste Panel, Scenario S6-BF
6.2 Spellings
Calculation of the volume of solid waste material released to the surface from a single drilling
intrusion into the repository due to spallings is a two-part procedure. First, the code DRSPALL
calculates the spallings volumes from a single drilling intrusion at four values of repository
pressure (103 12, 14. and 14.8 MPa). The second step in calculating spallings volumes from a
single intrusion consists of using the code CUTTINGS_S to interpolate between DRSPALL
volumes. The spallings volume for a given vector is determined in CUTTINGS_S by linearly
interpolating between volumes calculated by DRSPALL based on the pressure calculated in each
realization by BRAGFLO. DRSPALL volumes used in the PABC-2009 were also used in the
SDI impact assessment.
PA code CUTTINGS_S is also used as a transfer program between the BRAGFLO Salado flow
calculation and the BRAGFLO DBR calculation. Results obtained by BRAGFLO for each
realization in scenarios Sl-BF to S5-BF are used to initialize the flow field properties necessary
for the calculation of DBRs. This requires that results obtained on the BRAGFLO grid be
mapped appropriately to the DBR grid. Code CUTTINGS_S is used to transfer the appropriate
scenario results obtained with BRAGFLO to the DBR calculation. These transferred flow results
are used as initial conditions in the calculation of DBRs. As a result, intrusion scenarios and
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times used in the calculation of spallings volumes correspond to those used in the calculation of
DBRs. Five intrusion scenarios are considered in the DRR calculations, and are listed in Table
3.
Table 3: PA Intrusion Scenarios Used in Calculating Direct Solids Releases
Scenario
Conditioning (or 1st)
Intrusion Time (year) and
Type
Intrusion Times - Subsequent
(year)
SI-DBR
None
100, 350, 1000, 3000. 5000, 10000
S2-DBR
350, El
550, 750, 2000, 4000, 10000
S3-DBR
1000, El
1200, 1400, 3000, 5000, 10000
S4-DBR
350, E2
550, 750, 2000, 4000, 10000
S5-DBR
1000, E2
1200, 1400,3000, 5000, 10000
While CUTTINGS_S uses these standard DBR scenarios as a basis for its calculations, it does so
to provide flow field results (generated with BRAGFLO) as initial conditions to the DBR
calculation at each subsequent intrusion time. CUTTINGS S does not model the intrusion
scenario itself. Scenario SI-DBR corresponds to an initial intrusion into the repository, with
repository flow conditions at the time of intrusion transferred from BRAGFLO scenario Sl-BF
results. Scenarios S2-DBR through S5-DBR are used to model an intrusion into a repository that
has already been penetrated. The times at which intrusions are assumed to occur for each
scenario are outlined in the last column of Table 3; six intrusion times are modeled for scenario
S1 -DBR, while five times are modeled for each of scenarios S2-DBR through S5-DBR.
Utilizing the spallings volumes calculated by DRSPALL and the SDI repository pressures
calculated by BRAGFLO, the impact of SDI excavation on spallings volumes can be determined.
Summary statistics of spallings volumes for the intrusion scenarios considered by CUTTINGSS
are shown in Table 4 for both the SDI impact assessment and the PABC-2009, PABC-2009
results reported in that table are taken from Ismail (2010). As seen in that table, values obtained
in the SDI Impact assessment are generally equal or lower overall when compared to those
obtained in the PABC-2009. For scenario SI-DBR, a consistent reduction in the number of
nonzero spallings volumes is seen across replicates R1 - R3 in the SDI impact assessment.
Moreover, the average and maximum spallings volumes seen in that scenario are lower in all
three replicates for the SDI calculation. Similar reductions are evident in scenarios S2-BF to
S5-BF. Overall, the general trend is an equal or lower maximum volume, an equal or lower
average volume, and a lower percentage of vectors resulting in nonzero spallings volumes in the
SDI calculation than were seen in the PABC-2009.
Spallings volumes are a function of repository pressure. Previous analyses have determined that
no tensile failure of repository material occurs at initial repository pressures less than 10 MPa,
and that no spallings are observed at pressures less than 13 MPa (Lord et al 2003). Thus, waste
failure and subsequent transport for spallings is assumed to be non-existent for repository
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pressures less than 10 MPa. As seen in the BRAGFLO results in Section 6.1, additional
excavation in the WIPP experimental area for SDI translates to an eventual pressure reduction in
waste-containing regions. As there is a minimum threshold pressure of 10 MPa required for a
spallings release, a decrease in repository pressure also decreases the percentage of vectors with
nonzero spallings volumes.
Table 4: Summary of Spallings Releases by Scenario
Scenarios
Total
Sl-DBR
S2-DBR
S3-DBR
S4-DBR
S5-DBR
SDI PA
Maximum [m3|
1.67
8.29
7.98
i.t>7
l.fv
R1
Average nonzero volume |m3|
0.35
0.54
0.55
0.29
0.37
0.43
Number of nonzero volumes
127
105
99
58
74
463
Percent of nonzero volumes
7.1%
7.0%
6.6%
3.9%
4.9%
5.9%
Maximum [m3]
2.17
2.74
1.73
2.26
1.93
2.74
R2
Average aoiztro volume [m3]
0.28
0.35
0.34
0.42
0.40
0.34
Number of nonzero volumes
145
100
108
54
80
487
Percent of nonzero volumes
8.1%
6.7%
7.2%
3.6%
5.3%
6.2%
Maximum [m3]
3.66
6.20
2.48
0.85
1.08
6.20
R3
Average nonzero volume [m3]
0.41
0.38
0.23
0.24
0.23
0.32
Number of nonzero volumes
140
92
98
36
63
429
Percent of nonzero volumes
7,8%
6.1%
6.5%
2.4%
4.2%
5.5%
PABC-2009
Maximum [m3]
2.24
8.29
7,97
1.67
1.67
8.29
R1
Average nonzero volume |m3|
0.37
0.54
0.50
0.30
0.37
0.43
Number of nonzero volumes
142
117
111
59
77
506
Percent of nonzero volumes
7.9%
7.8%
7.4%
3.9%
5.1%
6.5%
Maximum fm3}
2.36
2.76
1.86
2.26
1.93
2.76
R2
Average nonzero volume [m3]
0.32
0.39
0.37
0.50
0.47
0.39
Number of nonzero volumes
168
122
122
57
84
553
Percent of nonzero volumes
9.3%
8.1%
8.1%
3.8%
5.6%
7.1%
Maximum [m3]
4.91
6.23
2.62
1.47
1.49
6.23
R3
Average nonzero volume [m3]
0,53
0.39
0.28
0.30
0.28
0.38
Number of nonzero volumes
156
113
118
45
72
504
Percent of nonzero volumes
8.7%
7.5%
7.9%
3.0%
4.8%
6.5%
The impacts of the changes in spallings volumes on the overall mean CCDF for normalized
spallings releases obtained in the SDI impact assessment can be seen in Figure 6-19. As seen in
that figure, the CCDF of spallings releases obtained in the SDI impact assessment is consistently
lower than that found in the PABC-2009. The overall reduction in spallings volumes and in the
number of vectors that result in a nonzero spallings volume translate to a reduction in spallings
releases as both analyses use the same waste inventory.
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Impact Assessment of SDI Excavation on Long-Term WIFP Performance
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1
a:
A 0.1
a>
(/>
ra
a>
CD
OH 0.01
4-»
!5
CO
o 0.001
al
0.0001
0.0001 0,001 0.01 0.1 1 10 100
R = Spallings Release (EPA Units)
Figure 6-19: SDI and PABC-2009 Overall Mean CCDFs for Normalized Spallings Releases
6-3 Direct Brine Releases
PA code BRAGFLO is used in two ways in WPP PA calculations. First, it is used to calculate
the flow of brine and gas in and around the repository for undisturbed and disturbed conditions.
SDI results from this application of BRAGFLO are shown in Section 6.1. Second, it is used for
the calculation of direct brine releases. These two uses of BRAGFLO require different
computational grids. The grid used to calculate brine and gas flow in and around the repository
is different than that used to calculate DBRs. However, results obtained from the brine and gas
flow calculation are used to initialize conditions in the DBR calculation. The representation of
the waste area by three regions in the SDI and PABC-2009 BRAGFLO grids (see Figure 6-1)
yields initial conditions to waste regions comprising the waste panel (panel 5), the South Rest of
Repository or SROR (panels 3,4,6, and 9), and the North Rest of Repository or NROR (panels
1,2,7,8, and 10) in the DBR calculation, with drilling intrusions considered in each of these
regions. The types of intrusions considered in the DBR calculation and the times at which they
occur are listed in Table 3. The DBR computational grid and drilling locations used for the SDI
impact assessment are identical to those used in the PABC-2009, and are shown in Figure 6-20.
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With the DBR computational grid and intrusion locations in hand, DBR results from the SDI
impact assessment and tire PABC-2009 can now be compared. Summary statistics of the
calculated DBR volumes for replicates 1-3 and scenarios SI-DBR to S5-DBR are provided in
Table 5. As was also the case in the PABC-2009, release volumes less than lxlO"7 m3 are
considered to be inconsequential and are not included in the tally of vectors that result in DBR
release volumes in the SDI calculations. In Table 5, maximums shown are the maximum DBR
volumes calculated over all replicates, times, vectors and drilling locations. As seen by the
statistics for the maximum DBR volumes in Table 5, the additional excavation to the W1PP
experimental area for SDI results in a decrease in the maximum DBR volume as compared to the
PABC-2009. The maximum DBR volume realized in the PABC-2009 was 48.2 m3 while that
seen in the SDI impact assessment is 42.3 m3. Additionally, the average DBR volume remained
equal or decreased in the SDI impact assessment for all scenarios considered. When calculated
over all intrusion scenarios and all nonzero releases, the average volumes are the same at 0.9 m3
in the PABC-2009 and in the SDI impact assessment. As seen in the BRAGFLO results of
Section 6.1, a reduction in the average pressure with a corresponding increase in average brine
Note: Model cells are not to scale. The actual
dimensions of the grid blocks are indicated along
the edge of the diagram
Figure 6-20: SDI and PABC-2009 DBR material map (logical grid).
] Waste
(2.4* 10°3 so? permeability)
I I Equivalent Panel Closure
CIZlDRZ
I Impure Halite
(Impermeable)
I Equivalent DRZ'Concrete
^ Boundary condition well
for previous El iutruuou
A Down-dip well first or
second intrusion
Up-dip well first or
second intrusion
T Middle welL first ct
second intrusion
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saturation was seen in waste-containing regions for all scenarios considered in the Salado flow
calculation. These changes effectively cancel each other out in the DBR calculation, resulting in
equal average DBR volumes in the SDI and PABC-2009 results. These changes have a slight
impact on the number of vectors resulting in nonzero DBR volumes, however. In the PABC-
2009, a total of 2,999 vectors resulted in a nonzero DBR volume realization. The number of
vectors resulting in nonzero DBR volumes in. the SD1 impact assessment is 2.880, a reduction by
119 vectors when compared to the PABC-2009 results.
Table 5: PABC-2009 and SDI PA DBR Volume Statistics
Scenario
Maximum Volume (m3l
Average Volume (m})
Number of Vectors
PABC-2009
SDI PA
PABC-2009
SDI PA
PABC-2009
SDI PA
SI DBR
27.6
18.5
0.1
0.1
369
356
S2-DBR
48.2
42.3
2.8
2.7
1179
1139
S3-DBR
40.6
42.1
1.5
1.5
926
901
S4-DBR
20.4
18.9
0.1
0.0
211
198
SS DBR
21.1
21.3
0.1
0.1
314
286
Sl-DBR to
S5-DBR
48.2
42.3
0.9
0.9
2999
2880
DBR releases are less likely to occur during upper drilling intrusions when compared with the
lower drilling location. Of all the intrusions that had a non-zero DBR volume for the SDI impact
assessment, 67.3% occurred during a lower drilling intrusion. Furthermore, of all the intrusions
that had a non-zero DBR volume and occurred during a lower drilling intrusion, 83.4% are found
in scenarios S2-DBR and S3-DBR. Therefore, the majority of the non-zero DBR volumes occur
when there is a previous El intrusion within the same panel. Not only are DBRs less likely to
occur during upper drilling intrusions, but also the DBR volumes from such intrusions tend to be
much smaller than DBR volumes compared to those of lower drilling intrusions. For all three
replicates of the SDI impact assessment, the maximum DBR volume for the upper drilling
1 'I •
location is 13.4 m compared to 42.3 m for the lower drilling location. These observations
support the conclusion that lower drilling intrusions are the primary source for significant DBRs.
This trend is similarly seen in the PABC-2009 DBR results.
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40
30
20
10
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50
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SDI PA S2-DBR Lower
—o—
Time=550
Time=750
A-
Time=2000
.... <-
Time=400Q
Percentile
Figure 6-21: All replicates for SDI scenario S2-DBR lower intrusions.
PABC-2009 S2-DBR Lower
20 40 60 80 100
Percentile
Figure 6-22, All replicates for PABC 2009 scenario S2-DBR lower intrusions
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The marked similarity in DBR volumes and trends between the PABC 2009 and the SDI impact
assessment is apparent by comparing S2-DBR volume percentiles. Figure 6-21 and Figure 6-22
present these results for the SDI impact assessment and the PABC-2009 across all three
replicates at the five times listed in Table 3. Those figures show the percentage of vectors on the
X-axis where DBR volumes are less than the value on the Y-axis. As is evident, all significant
aspects of these curves are almost identical, with the exception of the maximum DBR volume
attained. SDI impact assessment maximum volumes are slightly lower than for the PABC 2009
results.
Figure 6-23 presents DBR volumes versus intruded panel pressure for all replicate 1, scenario
S2-DBR lower intrusions. For a nonzero DBR volume to be realized, the repository pressure
near the drilling location must exceed the hydrostatic pressure of the drilling fluid, which is
specified in PA to be 8 MPa. As a result, there are no releases at panel pressures less than 8 MPa
in Figure 6-23. The data in that figure are segregated into mobile brine saturation fractions, for
which higher numbers indicate more mobile brine available to flow up an intrusion borehole. It
is noted in this figure that low mobile brine values lead to low DBR releases, as expected.
Mobile Brine
Saturation fraction
o 0-0.2
O 0.2-0.4
o 0.4-0.6
X
* 0.6-0.8
° it
0.8-1,0
X Q
+ 0
"#• A
vQfK O
* ~ ~ 4 ~
° •
>*
° Jr**
O q ~~ O D
A™ ° n °° 0
JPoaQ0 0 ' Q a
'~t? fn V ftfl ^ tK>! s ,
0 2 4 6 8 10 12 14 16 18
Pressure, MPa
Figure 6-23: SDI DBR Volume vs. Pressure, Scenario S2-DBR, Replicate 1, Lower Intrusion
To further facilitate comparisons of DBRs calculated in the SDI impact assessment to those
obtained in the PABC-2009, the overall mean CCDFs obtained in these two analyses are plotted
simultaneously in Figure 6-24. As seen in that figure, the CCDF curves obtained for direct brine
releases in the PABC-2009 and the SDI impact assessment are virtually identical. Additional
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excavation in the WIPP experimental area for SDI has slight impacts on pressures and brine
saturations in waste-containing regions. These slight changes impact the number of vectors that
result in nonzero DBR volumes, with slight reductions seen in the SDI impact assessment.
Taken collectively, however, these slight changes result in negligible differences between the
DBR CCDF curve obtained in the SDI impact assessment and that found in the PABC-2009.
R = Direct Brine Release (EPA Units)
Figure 6-24: SDI and PABC-2009 Overall Mean CCDFs for Normalized Direct Brine Releases
6.4 Total Normalized Releases
Total normalized releases for the SDI impact assessment are presented in this section and
subsequently compared to results obtained in the PABC-2009. Total releases are calculated by
forming the summation of releases across each potential release pathway, namely cuttings and
cavings releases, spallings releases, direct brine releases, and transport releases. As prescribed in
AP-156 (Camphouse & Kuhlman 2011), transport results obtained in the PABC-2009 are also
used in the SDI calculations. SDI CCDFs for total releases are presented in Figure 6-25, Figure
6-26, and Figure 6-27 for replicates 1, 2, and 3, respectively. These curves are virtually
unchanged from those found in the PABC-2009. Mean and quantile CCDF distributions for the
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Impact Assessment ofSDI Excavation on Long-Term WIPP Performance
Revision I)
three replicates are shown together in Figure 6-28. Figure 6-29 contains the 95 percent
confidence limits about the overall mean of total releases. As seen in Figure 6-29, the overall
mean for normalized total releases and its lower/upper 95% confidence limits are well below
acceptable release limits. As a result, the additional SDL excavation in the WIPP experimental
area does not result in WIPP non-compliance with the containment requirements of 40 CFR Part
191.
The SDI impact assessment and PABC-2009 overall mean CCDFs for total releases are virtually
identical (Figure 6-30), Cuttings and cavings releases and direct brine releases are the two
primary release components contributing to total releases found in the SDI calculations (Figure
6-31). Additional excavation in the WIPP experimental area for SDI has no impact on cuttings
and cavings releases. Consequently, SDI cuttings and cavings results are unchanged from those
found in the PABC-2009. As discussed in Section 6.3, the excavation envisioned for SDI has a
negligible impact on direct brine releases.
A comparison of the statistics on the overall mean for total normalized releases obtained in the
SDI calculations and the PABC-2009 can be seen in Table 6. In that table, PABC-2009 values
are taken from Camphouse (2010), At probabilities of 0.1 and 0.001, values obtained for mean
total releases are nearly identical in both analyses and are indistinguishable statistically.
Table 6: SDI PA and PABC-2009 Statistics on the Overall Mean for Total Normalized Releases in EPA Units at
Probabilities of 0.1 and 0.001
Probability
Analysis
Mean Total
90th
Lower
Upper
Release
Release
Percentile
95% CL
95% a
Limit
0.1
SDI PA
0.093
0.15
0.090
0,095
1
PABC-2009
0.094
0.16
0.091
0.096
1
0.001
SDI PA
1.1
1.0
0.38
1.8
10
PABC-2009
1.1
1.0
0.37
1.8
10
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Impact Assessment of SDI Excavation on Long-Term WIPP Performance
Revision 0
0.0001 0.001 0.01 0.1 1 10 100
R = Total Release (EPA Units)
Figure 6-25: SDI Replicate 1 Total Normalized Releases
0,0001 0.001 0.01 0.1 1 10 100
R = Total Release {EPA Units)
Figure 6-26: SDI Replicate 2 Total Normalized Releases
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Impact Assessment of SDI Excavation on Long-Term WIPP Performance
Revision 0
R = Total Release (EPA Units)
Figure 6-27: SDI Replicate 3 Total Normalized Releases
0.1 T
0.01 -
0.001 -
0.0001
0.0001
0.001
Replicate 1 Mean
Replicate 1 10th percentile
Replicate 1 90th percentile
Replicate 2 Mean
Replicate 2 10th percentile
Replicate 2 90th percentile
Replicate 3 Mean
Replicate 3 10th percentile
Replicate 3 90th percentile
Release Limits
100
R = Total Release (EPA Units)
Figure 6-28: SDI Mean and Quantile CCDFs for Total Normalized Releases, Replicates 1-3
Page 3 7 of 60
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Impact Assessment of SDI Excavation oil Long-Term WIPP Performance
Revision 0
Mean Total
Lower 95% CL
Upper 95% CL
Release Limits
* 0.1 -
A
0.01 -
Jr
2
{3
-Q
£ 0-001 -
0.0001 i 1 I 1 1—I I I I I I 1 T HTTTTI r •' 'I TTTTTf r^l—I I I 1 111 1 1—I TTTTT
0.0001 0.001 0.01 0.1 1 10 100
R = Release
Figure 6-29: SDI Confidence Limits on Overall Mean for Total Normalized Releases
SDI Overall Mean
PABC-2009 Overall Mean
Release Limits
D.0001 0.001 0.01 0.1 1 10
R = Total Release (EPA Units)
Figure 6-30; SDI and PA60-2009 Overall Mean CCDFs for Total Normalized Releases
100
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Impact Assessment of SDI Excavation on Long-Term WIPP Performance
Revision 0
R - Release (EPA Units)
Figure 6-31: SDI Primary Components Contributing to Total Releases
7 SUMMARY
Total normalized releases calculated in the SDI impact assessment remain below their regulatory
limits. As a result, the additional excavation in the WIPP experimental area to support SDI
would not result in WIPP non-compliance with the containment requirements of 40 CFR Part
191, Cuttings and cavings releases and direct brine releases are the two primary release
components contributing to total releases in the SDI calculations. Cuttings and cavings releases
are unchanged from those calculated in the PABC-2009. Additional excavation for SDI results
in small changes to pressures and brine saturations in repository waste-containing regions, but
these collectively result in a negligible difference between direct brine releases seen in the SDI
impact assessment and the PABC-2009, Small reductions are observed in SDI spallings releases
as compared to the PABC-2009, but these differences are relatively minor and do not have a
significant impact on the overall total normalized releases found in the SDI impact assessment.
Total normalized releases found in the SDI calculations and the PABC-2009 are
indistinguishable.
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Impact Assessment of SDI Excavation on Long-Term WIPP Performance
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8 REFERENCES
Camphouse, R.C. 2010. Analysis Package for CCDFGF: CRA-2009 Performance Assessment
Baseline Calculation. SandiaNational Laboratories, Carlsbad, NM. ERMS 553027,
Camphouse, R.C. and Kuhlman, K.L. 2011. Analysis Plan for the Impact Determination of SDI
Heater Testing and Associated Excavation on Long-Term WIPP Performance. Sandia National
Laboratories, Carlsbad, NM. ERMS 555540.
Chavez, M. J. 2006b. Nuclear Waste Management Procedure NP 19-1: Software Requirements,
Revision 12, ERMS 543743 Sandia National Laboratories, Carlsbad, NM.
Clayton, D.J., R.C. Camphouse, J.W. Garner, A.E. Ismail, T.B. Kirchner, K.L. Kuhlman, M.B.
Nemer, 2010. Summary Report of the CRA-2009 Performance Assessment Baseline Calculation.
Sandia National Laboratories, Carlsbad, NM. ERMS 553039.
Ismail, A.E. 2010, Analysis Package for Cuttings, Cavings, and Spallings: CRA-2009
Performance Assessment Baseline Calculation. Carlsbad, NM: Sandia National Laboratories.
ERMS 552893.
Kirchner, T.B. 2009. Generation of the LHS Samples for the AP-145 (PABC09) PA
Calculations. Sandia National Laboratories, Carlsbad, NM. ERMS 552905.
Kirkes. G.R. 2011. Features, Events and Processes Assessment for Changes Described in
Analysis Plan - 156 Salt Disposal Investigations, Revision 0. Sandia National Laboratories,
Carlsbad, NM. ERMS 555671.
Kuhlman, K. 2011. Analysis Report for SDI Heater Testing Long-Term Thermal Effects
Calculations, Revision 0, [AP-156]. Sandia National Laboratories, Carlsbad, NM. ERMS
555622.
Long, J.J. 2010. Execution of Performance Assessment Codes for the CRA-2009 Performance
Assessment Baseline Calculation, Revision 0. Sandia National Laboratories, Carlsbad, NM.
ERMS 552947.
Lord, D., D. Rudeen, and C. Hansen 2003. Analysis Package for DRSPALL: Compliance
Recertification Application: Part 1—Calculation of Spall Volumes. Carlsbad, NM. Sandia
National Laboratories. ERMS 532766.
U.S. Department of Energy (DOE) 2011a, Direction Letter for SDI Field Testing Planned
Change Notice. U.S. Department: of Energy Waste Isolation Pilot Plant, Carlsbad Area Office,
Carlsbad, NM. ERMS 555494,
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Impact Assessment of SDI Excavation on Long-Term WIPP Performance
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U.S. Department of Energy (DOE) 2011b. Inputs and Information for the SDI Thermal Test
Planned Change Notice. U.S. Department of Energy Waste Isolation Pilot Plant, Carlsbad Area
Office, Carlsbad, N.M. BRMS 555495.
U.S. Environmental Protection Agency (EPA). 1996. 40 CFR Part 194: Criteria for the
Certification and decertification of the Waste Isolation Pilot Plant's Compliance with the 40
CFR Part 191 Disposal Regulations; Final Rule. Federal Register, Vol. 61, 5223-5245.
U.S. Environmental Protection Agency (EPA). 2010. 40 CFR Part 194 Criteria for the
Certification and decertification of the Waste Isolation Pilot Plant's Compliance With the
Disposal Regulations: Recertification Decision, Federal Register No. 222, Vol. 75, pp. 70584-
70595, November 18, 2010.
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Impact Assessment of SDI Excavation on Long-Term WIPP Performance
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APPENDIX A SDI Code Execution
As mentioned in Section 1 and outlined in AP-156 (Camphouse and Kuhlman 2011). the SDI
impact assessment is essentially a focused re-run of the PABC-2009 calculation using a slightly
modified numerical grid in the Salado flow calculation. Execution and ran control for the
PABC-2009 are documented in Long (2010), The hardware and operating system used in the
SDI impact assessment are identical to those used in the PABC-2009, and are shown in Table 7.
Table 7: W'IPP PA Alpha Cluster Nodes Used in SDI Calculations
Node
Hardware Type
# of CPUs
CPU
Operating System
TBB
HP AlphaServer ES47
4
Alpha EV7
Open VMS 8.2
TRS
HP AlphaServer ES47
4
Alpha EV7
Open VMS 8.2
GNR
HP AlphaServer ES47
4
Alpha EV7
Open VMS 8,2
MC5
HP AlphaServer ES47
4
Alpha EV7
Open VMS 8.2
CCR
HP AlphaServer ES45 Model 2
4
Alpha EV68
Open VMS 8.2
TDN
HP AlphaServer ES45 Model 2
4
Alpha EV68
Open VMS 8.2
BTO
HP AlphaServer ES45 Model 2
4
Alpha EV68
Open VMS 8,2
CSN
HP AlphaServer ES45 Model 2
4
Alpha EV68
Open VMS 8.2
Determining the impact of additional SDI excavation on spallings and DBRs as compared to the
PABC-2009 is the primary focus of the SDI impact assessment. Quantifying these impacts
requires an execution of the Salado flow, spallings, DBR, and CCDFGF PA code chains. The
necessary suite of codes that were executed in the SDI impact assessment is listed in Table 8, and
has been qualified under Nuclear Waste Management: Procedure NP 19-1: Software
Requirements (Chavez 2006).
Table 8; WIPP PA VMS Software Used in the SDI Calculations
Code
Version
Executable
Build
CMS
CMS
Date
Library
Class
ALGEBRACDR
2.35
ALGEBRACDB_PA96.EXE
31-01-96
LIBALG
PA96
BRAGFLO
6.0
BRAGFLO QB0600.EXE
12-02-07
LIBBF
QB0600
PREBRAG
8,00
PREBRAG_QA0800.EXE
08-03-07
LIBBF
QA0800
POSTBRAG
4.00 A
POSTBRAG_ QA0400A.LXE
28-03-07
LIBBF
QA0400A
CCDFGF
5.02
CCDFGF_QB0502.EXE
13-12-04
L1BCCGF
QB0502
PRECCDFGF
1.01
PRECCDFGF QA0101 .EXE
07-07-05
LIBCCGF
QA0101
CUTT1NGS_S
6.02
CUT TINGS_S. Q AO602. EXE
09-06-05
LIBCUSP
QA0602
GENMESH
6.08
GM_PA96.EXE
31-01-96
LIBGM
PA96
ICSET
2.22
ICSET_PA96.EXE
01-02-96
LIB1C
PA96
POSTLHS
4.07A
POSTLII S_QA0407A.EXE
25-04-05
LIBLHS
QA0407A
MATSET
9.10
MAT8ET_QA0910.EXE
29-11-01
LIB MS
QA0910
RELATE
1.43
RELATE_PA96 .EXE
06-03-96
LIBREL
PA96
SUMMARIZE
3.01
SUMMARIZE QB030i,EXE
21-12-05
LIBSUM
QB0301
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Discussion of run control is limited to the execution of codes done for the SDI impact
assessment. Discussion of run control for PARC-2009 results used in the SDI calculation can be
found in Long (2010).
A.I Salado Flow Calculations (BRAGFLO)
Brine and gas flow in and around the repository and in overlying formations is calculated using
the BRAGFLO suite of codes (PREBRAG, BRAGFLO, and POSTBRAG) in conjunction with
several utility codes. The brine and gas flow calculations are divided into several steps. The
steps, the codes run in each step, and the DCL script(s) used to perform the step are shown in
Table 9.
Table 9: Salado Flow Run Control Scripts
Step
Codes In Step
Script(s)
CMS Library
CMS Class
1
GENMESH
MATSET
EVAL GENERIC STEP1.COM
LIBSD1 EVAL
SDI-0
2
POSTLHS
EVAl, GENERIC_STEP2.COM
LIB SDI EVAL
SDI-0
3
ICSET
ALGEBRACDB
EVAL_BF_STEP3 .COM
L1BSDI EVAL
SDI-0
4
PREBRAG
EVAL_BF_STEP4.COM
HBSDI EVAL
SDI-0
5
BRAGFLO
POSTBRAG
EVAL BF STEP5 MASTER.COM
LIBSDI EVAL
SDI-0
ALGEBRACDB
EVAl ,__BF STEPS SLAVE.COM
LIBSDTJEVAL
SDI-0
A.l.l Salado Flow Step 1
Step 1 uses GENMESH and MAT SET to generate the computational grid and assign material
properties to element blocks. Step 1 is run once. The input and log files for the Step 1 script as
well as the input and output files for GENMESH and MATSET are shown in Table 10.
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Table 10: Salado Flow Step 1 Input and Output Files
File Names
CMS Library
CMS Class
SCRIPT
Input
EVAL BF SDI STEP1 .INP
LIBSDI EVAL
SDI-0
Log
EVAL BF SDI STEP 1 .LOG
LIBSDI BF
SD1-0
GENMESH
Input
GM_BF._SDl.INP
LIBSDI BF
SD1-0
Output
GM BF SDI.CDB
LIBSDI BF
SDI-0
Output
GM BF SDI.DBG
NOT KEPT
NOT KEPT
MATSET
Input
MS BF SDI.INP
LIBSDIBF
SDI-0
Input
GM BF SDI.CDB
LIBSDIBF
SDI-0
Output
MS BF SDI.CDB
LIBSDI BF
SDI-0
Output
MS BF SDI.DBG
NOT KEPT
NOT KEPT
A.1.2 Salado Flow Step 2
Step 2 uses POSTLHS to assign the sampled parameter values used by BRAGFLO (generated by
LHS) to the appropriate materials and element block properties. Step 2 is run once per replicate.
POSTLHS loops over all 100 vectors in the replicate. The input and log files for the Step 2
script as well as the input and output files for POSTLHS are shown in Table 11.
Table II: Salado Flow Step 2 Input and Output Files
File Names1,2
CMS Library
CMS Class
SCRIPT
Input
EVAL BF SDI STEP2Rr.INP
LIBSDI EVAL
SDI-0
Log
E VAL BF SDI STEP2 Rr.LOG
LIBSDI BF
SDI-0
POSTLHS
Input
T.HS3 DUMMY.INP
LIBPABC09 LHS
SDI-0
Input
LHS2 PABC09 Rr CON.TRN
LIBPABC09 LHS
SDI-0
Input
MS BF SDI.CDB
LIBSDI BF
SDI-0
Output
LHS3 BF SDI Rj-^Vvw.CDB
LIBSDI BF
SDI-0
Output
LHS3 BF SDI Rr.DBG
LIBSDIBF
SDI-0
1. re{l, 2, 3}
2. vvv e {001, 002. ..., 100} for each r
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A.1.3 Salado Flow Step 3
Step 3 assigns initial conditions with ICSET and performs some pre-processing of input data
with ALGEBRACDB. Since ALGEBRACDB is used in multiple BRAGFLO steps, this use is
referred to as ALG1. Step 3 is run once for each replicate. The script loops over all 100 vectors
in the replicate. The input and log files for the Step 3 script as well as the input and output files
for ICSET and ALGEBRACDB are shown in Table 12.
Table 12: Salado Flow Step 3 Input and Output Files
File Names1'2
CMS Library
CMS Class
SCRIPT
Input
EVAL RF SDI STEP3 Rr.INP
LIBSDIEVAL
SD1-0
Log
EVAL BF SDI STEP3 Rr.LOG
LIBSDI BF
SDI-0
ICSET
Input
IC BF SDI.1NP
LIBSDI BF
SDI-0
Input
I.HS3 BF SDI Rr Vwv.CDB
LIBSDI BF
SDI-0
Output
IC BF SDI R/- Vwv.CDB
LIBSDI BF
SDI-0
Output
IC BF SDI Rr Vvvv.DBG
NOT KEPT
NOT KEPT
ALGEBRACDB
Input
ALG1 _BF_ SDI .INP
LIBSDI.BF
SDI-0
Input
IC BF SDI Rr Vwv.CDB
LIBSDIBF
SDI-0
Output
ALG IB F SDI Rr Vwv.CDB
LIBSDI BF
SDI-0
Output
ALG 1 RF SDI Rr Vwv.DBG
NOT KEPT
NOT KEPT
1. fe{l, 2, 3}
2. VVV 6 {001,002 100} fov each r
A.1.4 Salado Flow Step 4
Step 4 consists of running the pre-processing code PREBRAG. Step 4 is repeated for each
replicate/scenario combination. The script loops over all 100 vectors in the replicate/scenario
combination. The input and log files for the Step 4 script as well as the input and output files for
PREBRAG arc shown in Table 13.
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Table 13: Salado Flow Step 4 Input and Output Files
File Names''1'3
CMS Library1,2
CMS Class
SCRIPT
Script Input
EVAL BF SDI STEP4 Rr_Sj.INP
LIBSDIEVAL
SDI-0
Script Log
EVAL BF SDI STEP4 Rr S.v.LOG
L1BSDI BFRrSs
SDI-0
PREBRAG
Input
BF1 SDI Ss.INP
LIBSDI BF
SDI-0
Input
ALG1 BF SDI Rr Vvvv.CDB
LIBSDI BF
SDI-0
Output
BF2 SDI Rr_S.s_Vvvv.INP
LIBSDI BFRrSs
SDI-0
Output
BF 1 _SDI_Rr_S.s_Vvvv.DBG
NOT KEPT
NOT KEPT
1. re{l. 2, 3}
2. s e {l, 2, 3, 4, 5, 6} for each r
3. vvv e {001,002,100} for each s
A.1.5 Salado Flow Step 5
Step 5 runs BRAGFLO, POSTBRAG, and ALGEBRACDB (ALG2). This step has been
separated from Step 4 to allow the analysts to edit/modify the BRAGFLO input file in cases
where the generic numerical control parameters are not sufficient to obtain a converged solution.
In the paragraphs that follow, the procedure for the general case is described first and then the
procedure followed to re-run certain replicate/scenario/vector combinations that were run with
modified BRAGFLO input files due to lack of or unreasonably slow convergence.
A.l.5.1 General Case
Two DCL run control scripts are used in Step 5. The master script is invoked once for each
replicate/scenario combination. The master script loops over all 100 vectors in the
replicate/scenario combination. For each vector, the master script writes an input file for the
slave script, and then calls the slave script with that input file to run BRAGFLO, POSTBRAG,
and ALGEBRACDB. The input and log files for the Step 5 script as well as the input and output
files for BRAGFLO, POSTBRAG, and ALGEBRACDB are shown in Table 14.
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Table 14: Salado Flow Step 5 Input and Output Files (Generic Case)
File Names',J'3'4
CMS Library1'1-'
CMS Class
MASTER SCRIPT
Input
EVAL BF SDI_STEP5_R/_S.«.INP
LIBSDIEVAL
SDI-0
Log
FVALJBF_SDI_STEP5_Rj-_Sj.LOG
LIBSDI BFRrSs
SDI-0
SLAVE SCRIPT
Log"
FVAL BF SDl STEP5 Rr_Ss Vvvv.LOG
LIBSDI BFRrSs
SD1-0
BRAGFLO
Input
BF2 SDIRrSs_Vvvv.lNP
LIBSDI BFRrSs
SDI-0
Input
BF2 SDI CLOSlJRE.DAT
LIBSDI BF
SDI-0
Output
BF2 SDI Rr Ss Vvvv.OUT
NOT KEPT
NOT KEPT
Output
BF2_SDI_Rr_S a_Vwv. SUM5
LIBSDI BF
SDI-0
Output
BF2 _S D1 _ Rr_S_ V v v v. B IN
NOT KEPT
NOT KEPT
Output
BF2 SDI Rr SsVvvv.ROT
NOT KEPT
NOT KEPT
Output
BF2 SDI Rr SsVvvv.RIN
NOT KEPT
NOT KEPT
POSTBRAG
Input
BF2 SDI Rr Sj Vwv.BIN
NOT KEPT
NOT KEPT
Input
ALG1 _ B F_ S DI _ R/"_ Vv v v. CDB
LIBSDI BF
SDI-0
Output
BF3 SDI Rj- S.v Vvw.CDB
LIBSDI BFRrSi1
SDI-0
Output
BF3 SDI Rr Ss_Vvw.DBG
NOT KEPT
NOT KEPT
ALGEBRACDB
Input
ALG2 BF SDI.INP
LIBSDIBF
SDI-0
Input
BF3 SDI Rr Ss Vvw.CDB
LIBSDI BFRrS.s
SDI-0
Output
ALG2 BF SDI Rr Ss Vvw.CDB
LIBSDI BFRrSs
SDI-0
Output
ALG2_BF_SDI_Rr_S.vVvvv.DBG
NOT KEPT
NOT KEPT
1. re{l, 2, 3}
2. s e {l, 2, 3, 4, 5, 6} for eath r
3. vw e {001,002, 100} for each ,?
4. The script inputs arc echoed into the log file, so the input file is not kept
5. Due to an error in the master script input file, the*.SUM output files were placed in CMS library LIBSDIBF
instead of the library for the replicate/scenario combination. Note that output files for simulations reported in
Table 15 (modified input runs) were archived in the correct libraries (LIBSDlBFRrSs).
A. 1.5.2 Modified BRAGFLO Input Case
In the few instances when BRAGFLO failed to converge using the generic numerical control
parameters, a new BRAGFLO input file was submitted by the analysts and the case was re-run in
a manner similar to that described above in Section A.1.5.1 In order to track these cases a
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special tag ("MOD") was inserted into the BRAGFLO input file name, as well as the master
script input file and log file names.
The replicate/scenario/vectors requiring modified BRAGFLO input files are shown in Table 15.
For all vectors listed in that table, simulation control parameter FTOLJSAT was increased from
the default value of lc-2 to a value of lc-1. With that modification, vectors listed in Table 15
were successfully run to the final time of 10,000 years. The modified file names arc shown in
Table 16. All other files have the same names as for the generic case. Files in the libraries from
the un-converged runs were replaced with files from the re-run.
Table 15; Salad© Flow Step 5 Modified Input Runs
Replicate
Scenario
Vectors
Ri
SI
29
R2
SI
99
S4
95,99
S5
99
R3
S3
35
Table 16; Saladu Flow Step 5 Modified Input Runs File Names
File Names1,1*5
CMS Library1,2
CMS Class
MASTER
SCRIPT
Input
EVAL BF SDI STEP5 Rr S.*_Vvvv MOD.JNP
I.IBSDI HVAL
SDH)
Log
EVAL_BF_SDI_STEP5_R^_Ss_ Vvw_MOD.LOG
LlBSDI_BFRrSs
SDI-0
BRAGFLO
Input
BF2 SD1 Rr Sj Vwv_MOD.INI'
LIBSDIJBFRrSj
SDI-0
1. re{l. 2, 3} as shown in Table 15
2. se{l, 2,3, 4, 5, 6} as shown in Table 15
3. vectors as shown in Table 15
A.2 Single-Intrusion Solids Volume Calculations (CUTTINGS S)
The total volume of radionuclide-contaminated solids that may reach the surface during a drilling
intrusion event is calculated by the CUTTINGS_S code. The single intrusion solids volume
calculations are divided into 3 steps. The codes run in each step, and the DCL script(s) used to
perform the steps are shown in Table 17. Step 3 also includes a small utility used to submit the
script to a batch queue.
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Table 17; Solids Volume (CUTTINGS S) Run Control Scripts
Step
Codes in Step
Scripts
Script CMS Library
Script CMS Class
1
GENMESIl
MATSET
EVAL_CU SP_STEP 1 .COM
LEBSDfEVAL
SDI-0
2
POSTLHS
EVAL_CUSP_STEP2.COM
LIBSDI EVAL
SDI-0
3
CUTTINGS S
EVAL_CUSP_STEP3, COM
SUB CUSP__STEP3.COM
L1BSDI EVAL
SDI-0
A.2.1 Solids Volume Step 1
Step 1 uses GEN MESH and MATSET to generate the computational grid and assign material
properties to element blocks. Stepl is run once. The input and log files for the script as well as
the input and output files for GENMESH and MATSET are shown in Table 18.
Table 18: Solids Volume Step 1 input and Output Files
File Names
CMS Library
CMS Class
SCRIPT
Input
E VAL_CU SP_SDI_STEP l.INP
LIBSDI EVAL
SDI-0
Log
EVAL CI JSP SDI S TEP 1 .LOG
LIB SDI. CUSP
SDI-0
GENMESH
Input
GM CUSI' SDI.IMP
LIBSDI CUSP
SDI-0
Output
GM CUSP SDI.CDB
LIBSDI CUSP
SDI-0
Output
GM_CUSP_SD1.DBG
NOT KEPT
NOT KEPT
MATSET
Input
MS CUSP SD1.1NP
LIBSDI CUSP
SDI-0
Input
GM CUSP SDI.CDB
LIBSDI CUSP
SDI-0
Output
MS CUSP SDI.CDB
LIBSDI CUSP
SDI-0
Output
MS_.CUSP SDI.DBG
NOT KEPT
NOT KEPT
A.2.2 Solids Volume Step 2
Step 2 uses POSTLHS to assign the sampled parameter values used by CUTTINGS S
(generated by LHS) to the appropriate materials and element block properties. Step 2 is run once
per replicate. POSTLHS loops over all 100 vectors in the replicate. The input and log files for
the script as well as the input and output files for POSTLHS are shown in Table 19.
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Table 19: Solids Volume Step 2 Input and Output Files
File Names1,2
CMS Library
CMS Class
SCRIPT
Script Input
EVAL CUSP SD1 STE-P2 Rr.rNP
LIBSDI EVAL
SDI-0
Script Log
EVAL CUSP SDI STEP2 Rr.LOG
LIBSDI CUSP
SDI-0
POSTLHS
Input
LHS3 DUMMY,INP
LIBPABC09 I.HS
SDI-0
Input
LHS2 PABC09 Rr CON.TRN
LIBPABC09 LHS
SDI-0
l.ljHll
MS._CUSP_SDI.CDB
L1BSDICUSP
SDI-0
Output
LHS3_CUSP_SDI_Rr_ V vw. CDB
LIBSDI_CUSP
SDI-0
Output
LHS3 €USP_SDI Rr.DBG
LIBSDI CUSP
SDI-0
1. re{l, 2, 3}
2. vvvelOO), 002,100} for eachr
A.2.3 Solids Volume Step 3
Step 3 runs the CUTTINGS S code, and is invoked for each replicate. The script generates the
CUTTINGSS master input control file. The CUTTINGS S code itself loops over scenarios,
intrusion times, intrusion locations, and vectors. The input and log files for the Step 3 script as
well as the input and output files for CUTTiNGSJS are shown in Table 20.
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Table 20: Solids Volume Step 3 Input and Output Files
File Names1'2'5'4'5
CMS Library''2
CMS Class
SCRIPT
Input
EVAL CUSP SDI STEP3 Rr.lNP
LIDSDI_EVAL
SDI-0
Output
C USP SDI MASTER RrlNP
LIB SDI CUSP
SDI-0
Log
EVAL_CUSP_SDI_STEP3_Rr.LOG
LIBSDI_CUSP
SD1-0
CUTTINGSJS
Input
CUSP. SDI_MASTER Rr.INP
LIB SDI,,, CUSP
SDI-0
Input
CUSP_SDL1NP
LIBSDI CUSP
SDI-0
Input
LHS3 CUSP SDT Rr Vvvv.CDB
LIBSDI_CUSP
SDI-0
Input
BF3 SDI Rr S.5 Vvvv.CDB
LIBSDI BFRrSi
SDI-0
Input
MS PALL DRSCRA1 BC_R/.OL'T
LiBCRA 1 BC_DRS
SDI-0
Output
CUSP SDI R/-.TBL
LIBSDICUSP
SDI-0
Output
CUSP SDI Kj- S.v TtUtt c Vvvv.CDB
L.I B SDI CUSPRrS.v
SDI-0
Output
CUSP SDI Rr.DBG
LIB SDI CUSP
SDI-0
1. re{l, 2, 3}
2. je{l, 2, 3. 4, 5} for each r
"{100350,1000,3000,5000,10000} for SI
3. Utttel {550,750,2000,4000,10000} for S2, S4
{1200,1400,3000,5000,10000} for S3, S5
4. ce{L, U, M} for each intrusion, time
5. wve{00l, 002. 100}for each c
A3 Single-Intrusion Direct Brine Release Calculations (BRAGFLO)
Single-intrusion direct brine release volumes are calculated using the BRAGFLO suite of codes
(PREBRAG, BRAGFLO, POSTBRAG), in conjunction with several utility codes. The steps, the
codes run in each step, and the DCL script(s) used to perform the step are shown in Table 21,
Table 21: Direct Brine Release Run Control Scripts
Step
Codes in Step
Seript(s)
Script CMS Library
Script CMS Class
1
GENMESH
MATSET
EVAL DBR STEP1.COM
LIBSDI EVAL
SDI-0
2
ALGEBRACDB
RELATE
ICSET
EVAL DBR STEP2.COM
SUB DBR_STEP2.COM
LIBSDI_EVAL
SDI-0
3
PREBRAG
BRAGFLO
POSTBRAG
ALGEBRACDB
EVAL_DBR_STEP3.COM
SUB DBR STEP3.COM
LIBSDI EVAL
SDI-0
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A.3.1 Direct Brine Release Step 1
Step 1 uses GENMESH and MATSET to generate the computational grid and assign material
properties to element blocks. Step 1 is run once. The input and log files for the script as well as
the input and output files for GENMESH and MATSET are shown in Table 22.
Table 22; Direct Brine Release Step 1 Input and Output Files
File Names
CMS Library
CMS Class
SCRIPT
Input
EVAL_DBR_SD1 STEP1 ,INP
LIBSDI EVAL
SDI-0
Log
EVAl._DBR SDI STEP I .LOG
LIB SDI DBR
SDI-0
GENMESH
Input
GM_DBR._SD1.1NP
LIBSDI DBR
SDI-0
Output
GM DI3RSDI.CDB
LTBSDI_DBR
SDI-0
Output
GMJDBRJ3DI.DBG
"NOT KEPT
NOT KEPT
MATSET
Input
MS DBR_ SDI.INP
LIBSDI DBR
SDI-0
Input
GM .DBR SD1.CDB
LIBSDI, DBR
SDI-0
Output
MS DBR SDI.CDB
LIBSDI DBR
SDI-0
Output
MS DBR SDI.DBG
NOT KEPT
NOT KEPT
A.3.2 Direct Brine Release Step 2
Step 2 performs pre-processing of input data with ALGEBRACDB (because ALGEBRACDB is
used in multiple steps, this use is referred to as ALG1). The RELATE code is used to assign
material properties to element blocks. RELATE is run twice (RELATE_l and RELATE 2).
Finally, ICSET is used to assign initial conditions. The Step 2 script is run for each
replicate/scenario combination. The script loops over the appropriate intrusion times for the
scenario. For each intrusion time, the script loops over all 100 vectors. The input and log files
for the Step 2 script as well as the input and output files for ALGEBRACDB, RELATE, and
ICSET are shown in Table 23.
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Table 23: Direct Brine Release Step 2 Input and Output Files
File Names1,w
CMS Library1,1
CMS Class
SCRIPT
Input
EVAL DBR SDI STEP2 Rr Ss.INP
LIBSDI EVAL
SDI-0
Log
EVAL DBR SDI STEP2 Rr Ss.LOG
LIBSDI DBRRrSs
SDI-0
ALCEBRACDB
Input
ALG1DBRSDI.INP
LIB SDI DBR
SDI-0
Input
CUSPS DI Rr_ SsJTf Wf _L _ V v v v. CDBJ
LIB SDI CUSPRrS.v
SDI-0
Output
ALG1 _DBR_SD I_R r_S.v_TtttttJV v v v. C D B
LIBSDI DBRRrSs
SDI-0
Output
ALGI DBR SDI Rr S.v Tttttt Vvvv.DBG
NOT KEPT
NOT KEPT
RELATE!
Input
REL1 DBR SDI.1NP
LIBSDI DBR
SDI-0
Input
MS DBR SDI.CDB
LIBSD1DBR
SDI-0
Input
ALG 1 _DBR_S DI_R/*_S.t_T«H/_V v vv.CDB
LIBSDI DBRRrSs
SDI-0
Output
REL1 DBR SDI Rr Ss Tttttt Vvvv.CDB
LIBSDI DBRRrSs
SDI-0
Output
REL1 DBR SDI Rr Ss Tttttt Vvvv.DBG
NOT KEPT
NOT KEPT
RELATE 2
Input
REL2 DBR SDI Ss.ENP
LIBSDI DBR
SDI-0
Input
REL1 DBR SDI Rr Ss Tttttt Vvvv.CDB
LIBSDI DBRRrSs
SDI-0
Input
BF3 SDI^Rr _S.!_ Vvvv.CDB
LIBSDI BFRrSs
SDI-0
Output
REL2 DBR SDI Rr Ss Tttttt Vvvv.CDB
LIBSDI DBRRrSs
SDI-0
Output
REL2_DBR_SDI_Rr_Si'_Tffrtf_Vvvv.DBG
NOT KEPT
NOT KEPT
ICSEI
Input
lC_DBR_SDl_Sf\INP
LIB SDI DBR
SDI-0
Input
REL2 DBR SDI Rr Ss Tttttt Vvvv.CDB
LIBSDI DBRRrSs
SDI-0
Output
IC DBR SDI Rr Ss Tttttt Vvvv.CDB
LIBSDI DBRRrSs
SDI-0
Output
IC__DBR__SDI_.Rr_Ss__Tffm_Vvvv.DBG
NOT KEPT
NOT KEPT
ALGEBRACDB
Input
ALG2 DBR SDI Ss.INP
LIBSDI DBR
SDI-0
Input
IC_D B R_S D I_Rr_S s_T tttll_y w v. C DB
LIBSDI DBRRrSs
SDI-0
Output
ALG2 DBR SDI Rr S.v Tttttt Vvvv.CDB
LIBSDI DBRRrSs
SDI-0
Output
ALG2 DBR SDI Rr Ss_Tttttt Vvvv.DBG
NOT KEPT
NOT KEPT
1. /-e{l. 2. 3}
2. ^e{l; 2, 3, 4, 5} for each r
'{00100, 00350. 01000, 03000, 05000, 10000} for SI
3. ttttt& {00550, 00750, 02000, 04000, 10000} for S2, S4
{01200,01400, 03000, 05000, 10000} for S3, S5
4. vw e {001, 002,100} for each intrusion
5. The files CUSP_SDI_Rr_Sy_Ttfftf_L_Vvvv.CDB do not have leading zeros in front of the intrusion time tlttl.
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A.3.3 Direct Brine Release Step 3
Step 3 runs PREBRAG,. BRAGFLO, POSTBRAG, and ALGEBRACDB (ALG3). The Step 3
script is invoked for each replicate/scenario combination. The script loops over the appropriate
intrusion times for the scenario. For each intrusion time, the script loops over all three intrusion
locations. For each intrusion location, the script loops over all 100 vectors. The PREBRAG,
BRAGFLO.. POSTBRAG, ALGEBRACDB sequence is run for each rcplicate/scenario/intrusion
time/intrusion location/vector combination. The input and log files for the Step 3 script as well
as the input and output files for PREBRAG, BRAGFLO, POSTBRAG, ALGEBRACDB are
shown in Table 24,
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Table 24: Direct Brine Release Step 3 Input and Output Files
File Names1,2,3AS
CMS Library1'2
CMS Class
SCRIPT
Input
EVAL_DBR_SDT_STEP3_Rr_S.v.IN P
LIBSDI EVAL
SDI-0
Log
EVAL DBR SDI STEP3 Rr Ss.LOG
LIBSDI_DBRRrS.v
SDI-0
PREBRAG
Input
BF1DBR SDI i\INP
LIBSDI DBR
SDI-0
Input
ALG2 DBR SDI Rr S^ Tttttt Vvvv.CDB
UBSDI DBRRrS.s
SDI-0
Output
BF2 DBR SDI Rr Ss Ttittt c Vvvv.INP
LIBSDI DBRRrSs
SDI-0
Output
BFI DBR SDI Rr S.v Tttttt c Vvvv.DBG
NOT KEPT
NOT KEPT
BRAGFLO
Input
B F2 _D B R_S D I_Rr _ S.?_Trt Vvvv.INP
LIBSDI DBRRrS«
SDI-0
Output
BF2 DBR SDI Rr Ss Tttttt c Vvvv.OUT
NOT KEPT
NOT KEPT
Output
BF2_DBR_SDI_Rr_S.y_Tttf«_c_V vvv. S UM
NOT KEPT
NOT KEPT
Output
BF2 DBR SDI Rr S.v Ttittt c Vvvv.BIN
NOT KEPT
NOT KEPT
Output
BF2 DBR SDI R^ Ss Trtftf c Vvvv.ROT
NOT KEPT
NOT KEPT
Output
BF2_DBR_SDI_Rr_S.y_T tittt_c_y vvv. RIN
NOT KEPT
NOT KEPT
POSTBRAG
Input
ALG2 DBR SDI Rr S.v Tttttt Vvvv.CDB
LIBSDI DBRRrS.v
SDI-0
Input
BF2_DBR_SDl_Rr__Sj_TtfW_c_Vvvv.BIN
NOT KEPT
NOT KEPT
Output
BF3 DBR SDIRrSs Ttittt c Vvvv.CDB
LIBSDI DBRRrSs
SDI-0
Output
BF3 DBR SDI Rr S.v Tttttt c Vvvv.DBG
NOT KEPT
NOT KEPT
ALGEBRACDB
Input
ALG3_DBR_SDI.INP
LIBSDI DBR
SDI-0
Input
BF3 DBR SDI Rr Ss Tttttt c Vvvv.CDB
LIBSDI DBRRrSs
SDI-0
Output
ALG3 DBR_SDI_Rr S.v T//W C Vvvv.CDB
LIBSDI JDBRRrSs
SDI-0
Output
ALG3DBRSD I_ Rr_S.?_ T tit tt_c_ Vvvv. DB G
NOT KEPT
NOT KEPT
1. re{l, 2, 3}
2. .ve{1, 2. 3, 4, 5) for each r
'{00100, 00350, 01000, 03000, 05000, 10000} for SI
3. tmt& {005 50, 00750, 02000, 04000, 10000} for S2, S4
{01200, 01400, 03000. 05000, 10000} for S3, S5
4. cs{L, M, U} for each intrusion
5. vvv e {001,002,100} for each c
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A.4 CCDF Input Tabulations (SUMMARIZE)
The output CDB files from the various process model codes are combined into text tables by the
SUMMARIZE code for subsequent use in calculating releases to the accessible environment.
The run control scripts used to process the CDB data for the various process models are shown in
Table 25. A single run control script is used to extract data from CDB files for all process model
codes. The script performs the following steps:
¦ Fetch the required CDB files
• Write an input control file for SUMMARIZE by filling in items in an input control file
template
• Run SUMMARIZE on the collection of CDB files
A small utility script is used to submit the main script to a batch queue.
Table 25: CCDF Input Tabulation Run Control Scripts
Code
Script
Script CMS Library
Script CMS Class
SUMMARIZE
EVAL_SUM.COM
SUB SUM.COM
L1BSDI EVAL
SD1-0
A.4.1 CCDF Input Tabulation for Direct Brine Release
SUMMARIZE is used to extract and tabulate brine release volume data from the appropriate
post-BRAGFLO DBR ALGEBRACDB output CDB files (see Section A.3 ). The run control
script is invoked for scenarios Sl-DBR through S5-DBR for each replicate. The script loops
over the appropriate intrusion times for each scenario. There is a single SUMMARIZE input
control file template, which the script uses to generate a SUMMARIZE input control file for
each repl icate/scenario/intrusion time/intrusion location combination. The script input and log
files along with the SUMMARIZE input and output files are shown in Table 26.
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Table 26; CCDF Input Tabulation Input and Output Files (Direct Brine Release)
File Names1,3'3'4'*
CMS Library1'1
CMS Class
SCRIPT
Input
EVAL__SUM_DBR_SDI_Rr_S.v.INP
LIBSDI EVAL
SDT-0
Input
SUM DBR SDI.TMPL
LIBSDI SUM
SD1-0
Output
SUM DBR SDI_Rr_&s_Tflfflf_c.INP
LIBSDI SUM
SD1-0
Log
EVAL_SUM_DBR_SDI_Rr_Ss.LOG
LIBSDI SUM
SDI-0
SUMMARIZE
Input
SUM_DB R_S DI _ R/-_S j_T . INP
LIBSDI SUM
SDI-0
Input
ALG3 DBR SDI Rr S.v Ttlltl c Vwv.CDH
LIB SDI _ D B RRr S.v
SD1-0
Output
SUM_DBR_SDT_Rr_&r_Tttttt_c.TBL
LIBSDI SUM
SDI-0
Output
SUM_DBR SDI_Rjr_Ss_Tttttt_c.DBG
NOT KEPT
NOT KEPT
1. «={ 1,2,3}
2. f e |l, 2, 3,4, 5} for each r
'{00100, 00350, 01000,03000, 05000, 10000} for SI
3. ttttiel (00550,00750, 02000, 04000, 10000} for S2 and S4
{01200, 01400, 03000, 05000, 10000} for S3 and S5
4. 1M, U} tor each intrusion lime
5. vvv e {001,002,100} lor cache
A.S CCDF Construction (PRECCDFGF, CCDFGF)
The complimentary cumulative distribution functions (CCDFs) for radionuclide releases to the
accessible environment are constructed using the PRECCDFGF/CCDFGF code suite. The
calculations are separated into several steps according to the number of times a particular code is
run and to allow for timely inspection of intermediate results. The steps, the codes run in each
step, and the DCL script(s) used to perform the steps are shown in Table 27.
Table 27: CCDF Construction Run Control Scripts
Step
Codes in Step
Scripts
CMS Library
CMS Class
1
GEN MESH
MATSET
EVAI ,_CCGF STEP 1 .COM
LIBSDI HVAL
SDI-0
2
POSTLHS
EVAL_CCGF_STEP2.COM
LIBSD1EVAL
SDI-0
3
PRECCDFGF
CCDFGF
EVAL CCGF STEP3 .COM
SUB_CCGF_STEP3 .COM
LIBSDI EVAL
SDI-0
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A.5.1 CCDF Construction Step 1
Step 1 uses GENMESH and MATSET to generate the computational grid and assign material
properties to element blocks. Step 1 is run once. The input and log files for the script as well as
the input and output files for GENMESH and MATSET and are shown in Table 28.
Tabic 28: CCDF Construction Step 1 Input and Output Files
File Names
CMS Library
CMS Class
SCRIPT
Script Input
EVAL CCGF SDI STEP1 INP
LIBSDI EVAL
SDI-0
Script Log
EVAL_CCGF_SDT_STEP I .LOG
LIB SDI CCGF
sdi-o
GENMESH
Input
GM CCGFSDI.INP
LIBSDICCGF
SDI-0
Output
GM._CCGF_SDI.CDB
LIBSDI CCGF
SDI-0
Output
GM_CCGF SDI DBG
NOT KEPT
NOT KEPT
MATSET
Input
MS CCGF SDL INP
LIBSDI CCGF
SDI-0
Input
GM CCGF SDI.CDB
LIBSDI_CCGF
SDI-0
Output
MS CCGF SDI.CDB
LIBSDI CCGF
SDI-0
Output
MS CCGF SDI.DBG
NOT KEPT
NOT KEPT
A.5.2 CCDF Construction Step 2
Step 2 uses POSTLHS to assign the sampled parameter values used by CCDFGF (generated by
LHS) to the appropriate materials and element block properties. Step 2 is run once per replicate.
POSTLHS loops over all 100 vectors in the replicate. The input and log files for the script as
well as the input and output files for POSTLHS are shown in Table 29.
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Table 29: CCDF Construction Step 2 Input and Output Files
File Names1'2
CMS Library
CMS Class
STEP 2
Script Input
EVAL_CCGF_SDI_STEP2Rr.lNP
LIBSDI. EVAL
SDI-Q
Script Log
EVAL_CCGF_SD1_STEP2_ Rr.LOG
LIB SDI CCGF
SD1-0
POSTLHS
Input
LHS3_DUMMY,INP
LIBPABC09 LHS
SDI-0
Input
LHS2 _PABC09_Rr_CX)N.TRN
LIBPABC09LHS
SD1-0
Input
MS_CCGF_SDI.CDB
LIBSDI CCGF
SDI-0
Output
LHS3_CCGF_SDI_Rr_Vvw.CDB
LIBSDI_CCGF
SDI-0
Output
LHS3._CCX5F_SDI_Rr.DBG
LIBSDI CCGF
SDI-0
1. re{l, 2, 3}
2. wv 6 {001,002,.,,, 100} for each r
A.5.3 CCDF Construction Step 3
Step 3 uses PRECCDFGF to organize and format output from all of the process model codes for
use by CCDFGF (i.e. builds the release table file), then runs CCDFGF to compute the CCDFs.
Step 3 is run once per replicate. The script loops over the appropriate scenarios and/or intrusions
and/or waste types to fetch the large number of data files that are input to PRECCDFGF. The
input and log files for the script as well as the input and output files for PRECCDFGF are shown
in Table 30.
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Table 30: CCDF Construction Step 3 Input and Output Kiles
File Names1"7
CMS Library
CMS Class
SCRIPT
Script Input
E V AL_C CG F_S TEP 3 _ S DI_Rr IN P
LIB SDI EVAL
SDI-0
Script Log
EVAL CCGF STEP3 SDI Rr.LOG
LIBSDICCGF
SDI-0
PRECCDFGF
Input
INTRUSIONTTM ES. IN
LIBPABC09_CCGF
SDI-0
Input
M S_CCGF_SD 1. CD B
LIB SDI CCGF
SDI-0
Input
LHS3_CCGF_SDI_Rr_Vvvv.CDB
L1BSDI CCGF
SDI-0
Input
SUM. DBR_SDI_Rr .Sj Jttttt c.TBL
LIBSDISUM
SDI-0
Input
CUSP_SDI_Rr.TBL
LIBSD1 CUSP
SDI-0
Input
SUM_NUT_P A BC 09 _R/*_S 1, TBI,
LIBPABC09_SUM
SDI-0
Input
SUM_NUT_PABC09_Rt_Sj_T ttttt. TBL
I.IBPABC09 SUM
SDI-0
Input
SUM_PANEL_INT_PABC09_Rr_S6jr«ttf.TBL
L1BPABC09 SUM
SDI-0
Input
SUM_ST2D_PABC09_Rr_M>w ,TBL
LIBPABC09_SUM
SDI-0
Input
EPU_PABC09_AH.DAT
LIBPABC09EPU
SDI-0
Input
SUM PANELCON PABC09 Ri- Ss.TBL
LIBPABC09_SUM
SDI-0
Input
SUM_PANEL_ST_PABC09_R/"_Ss.TBL
LIBPABC09 SUM
SDI-0
Output
CCGF_SDI_RELTAB_Rr.DAT
LIBSDI_CCGF
SDI-0
CCDFGF
Input
CCGF SDI CONTROL Rr.INP
LIBSDICCGF
SDI-0
Input
CCGF_SDI_RELTAB_Ry. DAT
LIBSDICCGF
SDI-0
Output
CCGF_SDI_Rr,OUT
LIBSDICCGF
SDI-0
Output
CCGF SDI Rr.DBG
NOT KEPT
NOT KEPT
1. re{l, 2, 3}
2. wv e {001, 002,.... 100} for each r
3. X 6
{1, 2, 3, 4, 5} for SUM_DBR
{2, 3. 4, 5} for SUMNIJT
{1,2} for SUM PANEL CON and SUM I'ANEL ST
4. ttttt C:
{00100, 00350, 01000, 03000, 05000, 10000} for SI for each r for SUM OUR
{00550, 07500, 02000, 04000,10000} for S2. S4 for each r for SUM_DBR
{ 01200, 01400, 03000, 05000,10000} for S3, S5 for each r for SUM DBR
{00100, 00350} for S2, S4 for each r for SUM__NUT
{01000, 03000, 05000, 07000, 09000} for S3, S5 each r for SUM_NUT
{00100, 00350, 01000, 02000,04000, 06000, 09000} for each r for SUM_F AN BLJNT
5. ce{L, M, U }fcrr each intrusion for SIJM DBR
6. /me{F, P}
7. h G {C. R]
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