Natural Analogs for the Unsaturated Zone Rev 00, ICN 00 

ANL-NBS-HS-000007

March 2000
 
1. PURPOSE 
The purpose of this Analysis/Model Report (AMR) is to document natural and anthropogenic 
(human-induced) analog sites and processes that are applicable to flow and transport processes 
expected to occur at the potential Yucca Mountain repository in order to build increased 
confidence in modeling processes of Unsaturated Zone (UZ) flow and transport. This AMR was 
prepared in accordance with AMR Development Plan for U0135, Natural Analogs for the UZ 
(CRWMS 1999a). Knowledge from analog sites and processes is used as corroborating 
information to test and build confidence in flow and transport models of Yucca Mountain, 
Nevada. This AMR supports the Unsaturated Zone (UZ) Flow and Transport Process Model 
Report (PMR) and the Yucca Mountain Site Description. 
The objectives of this AMR are to test and build confidence in the representation of UZ processes 
in numerical models utilized in the UZ Flow and Transport Model. This is accomplished by: 
 Applying data from Box Canyon, Idaho in simulations of UZ flow using the same 
methodologies incorporated in the Yucca Mountain UZ Flow and Transport Model to 
assess the fracture-matrix interaction conceptual model. 
 Providing a preliminary basis for analysis of radionuclide transport at Pea Blanca, 
Mexico as an analog of radionuclide transport at Yucca Mountain. 
 Synthesizing existing information from natural analog studies to provide corroborating 
evidence for representation of ambient and thermally coupled UZ flow and transport 
processes in the UZ Model. 
Natural analogs do not provide an analysis or model in and of themselves, but can be used to test 
conceptual and numerical models over large spatial and temporal scales not accessible to 
laboratory or field experiments. In this sense they are uniquely suited to building confidence in 
process models and in this manner are used by other AMRs as a means of model validation. 
However, natural analogs should be applied with caution, as they often have limitations; their 
boundary conditions and initial conditions may be unknown or they may have been inadequately 
characterized. The purpose of this work is, first, to catalog natural analog studies of unsaturated 
sites that were conducted by a variety of organizations in different countries and, second, to use 
information from carefully selected natural analog unsaturated sites to provide confidence in 
understanding how flow and transport in the unsaturated zone at Yucca Mountain would occur 
over thousands of years. 
Analog sites discussed in relation to the Yucca Mountain unsaturated zone (UZ) flow and 
transport model include the following: (1) Rainier Mesa, Nevada, an area close to Yucca 
Mountain with similar climatic and geologic conditions; (2) Box Canyon, Idaho, a site to test 
numerical modeling methodology of flow in fractured porous media; (3) Pea Blanca, Mexico, a 
uranium ore deposit in fractured rhyolitic tuff for building confidence in understanding of 
radionuclide transport along preferential pathways; (4) volcanic rock-hosted uranium deposits 
that occur in the unsaturated zone in northern Nevada and southeastern Oregon; and (5) various 
active geothermal and fossil hydrothermal sites for building confidence in modeling coupled 
thermal-hydrologic-mechanical-chemical (THMC) processes. Results of the analog studies will

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be used to corroborate estimates of the magnitude and limitation of operative processes in order to 
build realism into conceptual and numerical process models that are used as a foundation of 
performance assessment in the representative case of post-closure safety. 

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2. QUALITY ASSURANCE 
This AMR was developed in accordance with AP-3.10Q, Analyses and Models. Other applicable 
Department of Energy (DOE) Office of Civilian Radioactive Waste Management (OCRWM) 
Administrative Procedures (APs) and YMP-LBNL Quality Implementing Procedures (QIPs) are 
identified in the AMR Development Plan for U0135, Natural Analogs for the UZ (CRWMS M&O 
1999a). 
This analysis was evaluated in accordance with QAP-2.0, Conduct of Activities, and determined 
to be non-Q. This is because the data that support it were collected as part of projects other than 
the Yucca Mountain Site Characterization Project (YMP) and are therefore non-Q. This AMR 
will be used to support performance assessment only in a confirmatory manner. Although the data 
utilized and results presented in this AMR are not required to be qualified, all work, documents, 
and data submittals comply with the current version of the U.S. DOE Office of Civilian 
Radioactive Waste Management (OCRWM) Quality Assurance Requirements and Description 
(QARD) DOE/RW-0333P (DOE 1998). This evaluation is documented in Activity Evaluation of 
PSS Activity 6105 Science Support (CRWMS M&O 1999b).

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3. COMPUTER SOFTWARE AND MODEL USAGE 
The software codes and routines used in this AMR are listed in Table 3-1. These were appropriate 
for the intended application and used only within their range of validation. The Q-status of these 
codes is provided in Attachment I and the Document Input Reference System (DIRS) database. 
The software program TOUGH2 (TOUGH2 V1.3, STN: 10061-1.3-00, Version 1.3) was obtained 
from configuration management per AP-SI.1Q Software Management and was reverified under 
AP-SI.1Q. 
This AMR used the generalized conceptual model of UZ flow and transport at Yucca Mountain 
against which to compare the selected analogs. The numerical approach taken for the UZ Flow 
and Transport Model was utilized in Section 6.5.1.1 of this AMR to evaluate flow and transport 
processes. Input and output files for these model runs are listed in Attachment II. 
The routines listed in Table 3-1 are for pre- and post-processing of input and output files for 
TOUGH2 V1.3. The documentation for these routines has been submitted to the Records 
Processing Center and is included as Attachment V. 
Standard spreadsheet (Excel 97 SR-1) and graphics plotting programs (Tecplot, Version 7.5) were 
also used and are not subject to software quality assurance requirements. 
The data for the isochron was fit in Section 6.5.2.1.4.2.3 with a commercially available, standard 
least squares fitting program. The fit was confirmed with an in-house Los Alamos National 
Laboratory (LANL) program that was adapted to run on the PC under the name Winfit. 
Table 3-1. Computer Software Codes and Routines 
Software Name Version 
Software Tracking 
Number (STN) 
Computer Platform 
TOUGH2 1.3 10061-1.3-00 DEC or SUN Workstation 
with UNIX OS 
Routine: 
perm.for 1.0 
ACC: 
MOL.19991011.0224 PC with DOS 
plot.for 1.0 MOL.19991011.0225 PC with DOS 
rocktype.for 1.0 MOL.19991011.0226 PC with DOS 
save2tec.for 1.0 MOL.19991011.0227 PC with DOS 
tough2tec.for 1.0 MOL.19991011.0228 PC with DOS 
trans_cal.for 1.0 MOL.19991011.0229 PC with DOS 
weight.for 1.0 MOL.19991011.0230 PC with DOS

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4. INPUTS 
4.1DATA AND P ARAMETERS 
Inputs for this AMR include the following: 
 Box Canyon, Idaho analog study in fractured, unsaturated basalt 
 Pea Blanca, Mexico existing information and new analyses of uranium-series data 
 Existing information from flow and seepage studies in the USA (e.g., Rainier Mesa, 
Apache Leap) 
 Existing information from potential radionuclide transport sites and coupled process 
analog sites 
The data described above were not generated for the Yucca Mountain Site Characterization 
Project (YMP) under an approved quality assurance program and are therefore non-Q (see 
Section 2). The reports are available for review through the Technical Information Center (TIC). 
All input data used for this AMR are listed in the DIRS included as Attachment I and the DIRS 
database. 
4.2 CRITERIA 
This AMR complies with the DOE interim guidance (Dyer 1999). The subparts of the interim 
guidance that apply to this analysis are those pertaining to the characterization of the Yucca 
Mountain site (Subpart B, Section 15), the compilation of information regarding the hydrology of 
the site in support of the License Application (Subpart B, Section 21(c)(1) (ii)), and the definition 
of hydrologic parameters used in performance assessment (Subpart E, Section 114(a)). 
4.3 CODES AND STANDARDS 
The use of codes (other than software codes) and standards is not applicable to this report. 

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5. ASSUMPTIONS 
The fundamental assumption underlying this AMR is that natural analogs are one credible means 
of building confidence in understanding flow and transport processes at Yucca Mountain and the 
conceptual and numerical models used to describe them. The justification for this assumption is 
the widespread, documented and accepted use of natural analogs throughout the worldwide 
scientific community in addressing natural system behavior thought to occur at a nuclear waste 
repository over millennia. Statements made in the literature survey portion of this report (parts of 
Sections 6.5.1, 6.5.2; Section 6.5.3) are based on this fundamental assumption. 
The same basic assumptions were used to analyze the Box Canyon site (Section 6.5.1.1) as were 
used to study variably saturated groundwater flow at Yucca Mountain. This is a direct 
consequence of applying the same model conceptualization of Box Canyon to that of Yucca 
Mountain, given the natural analog premises motivating this work. 
Assumption 1. It is assumed that the dual-permeability representation of water- and gas-phase 
flow through both the fracture and matrix continua of the basalt is applicable to 
the Box Canyon site. This methodology was adopted to be consistent with the 
approach used at Yucca Mountain. This assumption is applied to all the 
analyses in Section 6.5.1.1. No further confirmation is needed for this 
assumption. 
Assumption 2. In adopting the dual-permeability approach, water and gas flow through the 
variably saturated fracture and matrix continua are assumed to be governed by 
the mass conservation equations discretized using the EOS3 module of 
TOUGH2 codes. This assumption is fundamental to the numerical analysis of 
all Yucca Mountain simulations and is used here by analogy. This assumption 
is applied to all the analyses in Section 6.5.1.1. No further confirmation is 
needed for this assumption. 
Assumption 3. Based on the observations of active water flow features given in Table 6-3, a 
conceptual fracture network was constructed and mapped onto a plan view of 
the mesh, as shown in Figure 6-5. Fractures above a dimensionless depth of 0.6 
are assumed to extend vertically downward from the ground surface. Active 
water flow features observed below a dimensionless depth of 0.6 are assumed 
to result from fractures extending from the bottom of the model upward. 
Fractures are assumed not to cross the dimensionless depth of 0.6 where the 
two cooling fronts intersected. The orientation of the fractures is assumed 
north-south, east-west to coincide with the orientation of the mesh. This 
orientation was chosen because it is on an approximate 45-degree angle with 
the E and S series of slanted boreholes and represents the fracture orientation 
angle that would maximize the probability of these boreholes intersecting a 
fracture. The fracture pattern was also selected so that two neighboring 
fractures within the same dimensionless depth were on average separated by a 
distance equal to the fracture spacing. Furthermore, the length of a fracture 
extending to either side of the actual observation point was also equivalent to 
the fracture spacing at the dimensionless depth of the observation point. This

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assumption was made in Section 6.5.1.1.3 and is applied throughout all the 
quantitative analyses in Section 6.5.1.1. Although other fracture patterns could 
be inferred from the data, their application would result in a comprehensive 
Monte-Carlo analysis which is beyond the scope of this work. 
Assumption 4. In the context of fracture continuum parameters,  weighting factors were used 
to increase the permeability and porosity of nodes where flow was actually 
observed to occur relative to the unconditioned background nodes. In 
particular, the  weighting factor of these nodes was chosen so that a single 
fracture exists at the node in the orientation shown in Figure 6-5. To prevent 
biasing nodes from increasing the net infiltration through the model but rather 
promote preferential channel flow through observed fracture flow features, the 
weighting factor of neighboring nodes was decreased. Hence, conservation of 
net infiltration flux was enforced by constraining the cumulative sum of the 
weighting factor for all biased nodes resulting from the observed flow feature 
to be identical to that of unconditioned nodes. The value and distribution of the 
weighting factors for nodes neighboring observed flow features were assumed 
for the purposes of this study. This assumption was made in Section 6.5.1.1.3 
and is applied throughout all the quantitative analyses in Section 6.5.1.1. 
Although other factors for decreasing weighting to neighboring nodes could be 
employed, insufficient data exist to justify any particular choice. Therefore, no 
further confirmation is needed for this assumption. 
Assumption 5. Permeabilities for the fracture continuum determined from pneumatic tests are 
assumed to be representative of the permeability of the fracture continuum to 
the water phase. Furthermore, the injected gas phase is assumed to advect 
through the fracture continuum only, thereby allowing the matrix continuum 
nodes to be removed during calibration. This assumption is consistent with the 
permeability calibration methodology employed in the unsaturated zone at 
Yucca Mountain. This assumption is applied in Section 6.5.1.1.4. The 
simulated pressure response was recalculated using the final Box Canyon 
model (with matrix continuum nodes) and yielded similar values. Therefore, 
no further confirmation is needed for this assumption. 
Assumption 6. Tsang (1992) provided a literature review to sort out the different definitions 
and denotations of the various equivalent apertures that arose due to field 
measurements regarding the relative magnitudes of hydraulic aperture and 
tracer aperture. These definitions pertained to representing a rough-walled 
fracture by a pair of parallel plates separated by a constant aperture b. In this 
work, we assume that the equivalent aperture obtained from the pneumatic, 
infiltration and tracer tests are identical by using the bromide data to infer the 
arrival time of the infiltration front. This assumption was applied to all the 
analyses in Section 6.5.1.1.5. No further confirmation is needed for this 
assumption. 
Assumption 7. Relative permeability and capillary pressure are described as continuous 
functions of effective liquid saturation following the expressions given by

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Corey and van Genuchten, respectively, as implemented in TOUGH2 codes 
(Pruess 1991). These functions are chosen to represent both water- and 
gas-phase flow through the matrix and fracture continua. The van Genuchten 
capillary pressure is the standard function used at Yucca Mountain and was 
adopted by analogy. The Corey relative permeability function was chosen 
rather than the standard van Genuchten representation because it provided a 
significantly more robust alternative for simulating the advection of infiltration 
fronts in the Box Canyon model. (Both the Corey and van Genuchten 
functions are empirical and are obtained by regressing parameters to measured 
laboratory data). Therefore, the Corey function was assumed adequate given 
that no relative permeability-water saturation data has been obtained at the Box 
Canyon site to substantiate the choice of a particular function. Furthermore, we 
assumed that residual water satuation in the fracture and matrix continua are 
0.01 and 0.1 respectively. These values were chosen to be identical to those 
used in the Yucca Mountain sitewide model because no data exists to identify 
their value at the Box Canyon site. However both the Box Canyon basalts and 
Yucca Mountain tufts are fractured volcanic rocks. This assumption was 
applied to all the analyses in Section 6.5.1.1.5. If uniqueness of calibration 
results were required, it would be necessary to confirm this assumption by 
collecting data regarding both water phase saturation and relative permeability 
at the Box Canyon site. However, for the evaluation of the appropriateness of 
the dual permeability approach, further confirmation is not required. 
Assumption 8. A precipitation rate of 1.0 m/yr was assumed at the Box Canyon site. 
Furthermore, 0.1 m/yr was assumed to infiltrate to the water table with the 
remainder lost to surface runoff and evaporation. Calibration of the model was 
not sensitive to this infiltration rate because both the matrix and fracture 
continua were not fully saturated under these conditions and were able to 
respond to the infiltration tests by absorbing excess water. This assumption 
was made in Section 6.5.1.1 and applies to all analyses within the section. This 
assumption does not require further investigation. 
Assumption 9. Background bromide concentrations resulting from the 96-1 infiltration test at 
Box Canyon (see Table 6-8) were assumed to be log-normally distributed 
based upon samples obtained prior to the 97-1 to 97-4 tests. This assumption 
was necessary to determine the ambient mean background concentration and to 
statistically determine a significant increase in bromide concentrations at a 
sampling point relative to ambient conditions. This assumption was applied to 
all the analyses in Section 6.5.1.1.5. No further confirmation is needed for this 
assumption. 
Assumption 10. The first significant increase in bromide concentration at a sampling point was 
assumed to indicate the arrival of the infiltration front. Therefore, it was 
assumed that the bromide tracer was conservative and advected at the same 
velocity as the infiltration front in the fracture continuum. The bromide tracer 
within the fracture will experience dilution as it diffuses into the matrix and

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disperses in the direction of flow. These processes were assumed not to 
attenuate the arrival of the bromide front below concentrations of 0.1 times the 
source concentration. The fractures are initially dry, so dispersion of the tracer 
relative to the water front should be negligible. In addition, the infiltration test 
is performed under unsaturated conditions. For the high-fracture-saturation 
water pulse, fracture/matrix exchange for both water and associated tracer is 
expected to be dominated by imbibition into the matrix. Under these 
conditions, matrix diffusion is expected to have negligible effects on the tracer 
concentrations along the infiltration front in the fracture water. This 
assumption was applied to all the analyses in Section 6.5.1.1.5. Calibrating 
hydrogeologic properties controlling infiltration front advection rate by using 
tracer (bromide) concentration measurements is a typical approach and, 
therefore, further confirmation of this assumption is not required. 
Assumption 11. The first sampling event when the bromide concentration exceeded 240 mg/l 
was used to infer the infiltration front arrival at that sampling point. These 
times are listed as the maximum bromide arrival time on Table 6-9. The 
sampling time immediately prior to when bromide exceeded 240 mg/l is listed 
as the minimum bromide arrival time on Table 6-9. Together, the maximum 
and minimum provide a window on the expected arrival time of the infiltration 
front at the sampling point. In some cases, the first bromide sample exceeded a 
concentration of 240 mg/l, setting the maximum value on the time window, but 
no prior sample was taken to set the minimum value on the window. In this 
case, the minimum arrival time of the infiltration front was set as the start of 
the 97-1 infiltration test by default. 
Assumption 12. A technical assumption made for the purposes of discussion in Section 6.5.3.2 
in the discussion of fracture sealing under heated conditions is that all matrix 
pore water flashes to steam in the fracture. This assumption was made to 
satisfy one end-member scenario. If the opposite occurs, i.e., if a drying front 
propagates into the matrix and deposits silica in the matrix, then an upper 
bound is provided for the extent of fracture sealing (Lichtner et al. 1999, p. 19). 
This assumption does not need verification.

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6. ANALYSIS/MODEL 
Key scientific notebooks (with relevant page numbers) used for the analysis described in this 
AMR are listed in Table 6-1. 
6.1 INTRODUCTION 
Natural analogs refer to natural or anthropogenic (human-produced) systems in which processes 
similar to those that are expected to occur in a nuclear waste repository are thought to have 
occurred over long time periods (decades to millennia) and large spatial scales (up to tens of 
kilometers). Analogs provide an important dimension to the understanding of processes that may 
take place in a nuclear waste repository and surrounding area. Analogs also provide an observable 
means of demonstrating whether the correct processes are represented in a total system 
performance assessment (TSPA). For some processes, such as those that are thermally coupled, 
natural analogs may be the only means of providing the required understanding of long-term and 
large-scale behavior that is needed to provide scientific confidence in process models that are 
used as input to total system performance assessment. Because the analogs are observable, they 
also perform the important illustrative function of bolstering public confidence in some aspects of 
nuclear waste disposal. However, analogs chosen for modeling must be selected carefully to 
exclude those for which initial and boundary conditions are poorly known and where important 
data, such as the source term, are poorly constrained. Even with these caveats in mind, it is 
important to examine natural analogs as a means of building confidence in understanding 
long-term behavior of both the natural and the engineered barrier systems. In this report we 
consider analogs for infiltration and flow processes (Section 6.5.1) as well as analogs to 
radionuclide transport processes (Section 6.5.2) and coupled THMC processes (Section 6.5.3) 
and discuss how each selected analog is used to test and build confidence in models of UZ flow 
and transport. 
6.2 CONCEPTUAL MODEL OF UNSATURATED ZONE FLOW AND TRANSPORT 
AT YUCCA MOUNTAIN 
The unsaturated zone (UZ) at Yucca Mountain is divided into five hydrogeologic units of 
alternating welded and nonwelded tuffs with contrasting hydrologic properties. Overlying these 
units are surficial deposits, designated Quaternary Alluvium (Qal), consisting of irregularly 
distributed deposits of alluvium and colluvium up to 30 m thick. These surficial alluvial deposits 
may be absent over large areas of the site, particularly on ridgetops and side slopes. The presence 
or absence of Qal and the slope aspect exert significant control over net infiltration at the site, 
with areas of thin or absent alluvium conducting moisture rapidly to the underlying tuff. Areas 
with thick alluvial cover accumulate moisture, where it is available for return to the atmosphere 
via evapotranspiration. 
Table 6-1. Scientific Notebooks 
LBNL Scientific Notebook ID M&O Scientific Notebook ID Accession Number Page numbers 
YMP-LBNL-AMS-NA-1 and 
Reference Binder 
YMP-LBNL-AMS-NA-1A 
SN-LBNL-SCI-108-V1 MOL.19990927.0459 1-8, 18-27, 
31-33, 53-61 
and binder 
1-97, A1-21 
YMP-LBNL-AMS-NA-AU-1 SN-LBNL-SCI-158-V1 MOL.19990927.0460 20-103

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Underlying the Qal is the Tiva Canyon welded hydrogeologic unit (TCw) (Montazer and Wilson, 
1984), a moderately to densely welded, devitrified ash flow tuff that may vary from 0 to 150 m in 
thickness. The fractured nature of the TCw and its relatively low porosity may facilitate moisture 
flux from the surface to below the zone of evapotranspiration. Below the TCw is the Paintbrush 
nonwelded unit (PTn), a 20 to 100 m thick sequence of partially welded to nonwelded, vitric and 
occasionally devitrified tuffs (Montazer and Wilson 1984, p. 14). Because it has significantly less 
fracturing and higher storativity than the welded units, the PTn may moderate moisture and gas 
phase fluxes between the surface and the repository horizon. 
Underlying the PTn is the potential repository host rock, the Topopah Spring welded 
hydrogeologic unit (TSw). The TSw is composed of moderately to densely welded, devitrified 
ash flow tuffs, 290 to 360 m thick. Average porosity of the TSw units is low, except for the vitric 
caprock or basal vitrophyre. Below the TSw unit is the Calico Hills nonwelded unit (CHn), a 100 
to 400 m thick sequence of nonwelded to partially welded ash flow tuffs. The CHn is divided into 
vitric (CHnv) and zeolitic (CHnz) facies. Perched water zones are generally found high in the 
CHn at the top of the CHnz, or at the TSw/CHn contact. 
The deepest of the six UZ units is the Crater Flat undifferentiated unit (CFu), which consists of 
0 to 200 m of undifferentiated welded and nonwelded, vitric, devitrified, and zeolitized ash flow 
and airfall tuffs. The CFu hydrofacies lies above the water table under the western margin and the 
southernmost half of the proposed repository block; toward the east and north, the unit lies above 
the water table, as does the CHn. 
Matrix saturated hydraulic conductivities measured on laboratory samples are small for the 
welded units (10-10 to 10-12 m/s for TCw, 10-11 m/s for TSw) and higher for the moderately 
welded to nonwelded units (10-7 m/s for the PTn, 10-9 m/s for TC moderately welded) (Flint 
1998, pp. 44-45). It is because of high bulk conductivities that fractures are thought to be well 
connected. Bulk conductivities are higher for the moderately to highly fractured welded units. 
Estimates of fracture densities for welded units are 10 to 20/m3 (TCw), and 8 to 40/m3 (TSw), 
while moderately welded units range from 1/m3 in the PTn to 2 to 3/m3 in the CHn (Montazer and 
Wilson 1984, p.1). High water potentials measured throughout much of the unsaturated zone 
indicate the absence of strong water potential gradients needed for matrix imbibition of fracture 
water (DOE 1998, p. 2-51). 
Hydrologic properties of the potential repository block-bounding faults is poorly understood. 
Whether they act as pathways, barriers, or are neutral to moisture flow is currently unknown; 
however, Fridrich et al. (1994) interpreted linear thermal highs coincident with north-trending 
normal faults as evidence for fault-controlled hydrostructural pathways from the Paleozoic 
carbonates to the overlying tuff aquifer system. Based on results of finding bomb-pulse 36Cl at the 
repository, fault zones may act as fast pathways through the repository horizon. Ahlers et al. 
(1999) showed pneumatic response data indicating that faults act as fast pathways for gas flow in 
the PTn and TSw. 
Precipitation in the vicinity of Yucca Mountain is approximately 17 cm/yr (Hevesi et al. 1992, 
p. 677). Net infiltration is variable but averages approximately 8 mm/yr (DOE 1998, p. 2-5). 
Percolation flux estimates vary from 0.01 to 21.1 mm/yr, depending upon location and method of

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estimation, but average around 7 mm/yr (DOE 1998, p. 25). At the repository horizon, 
percolation flux ranges from 1 to 20 mm/yr (DOE 1998, p. 25. Even though the average 
percolation flux may vary within this range over a scale of tens of meters, local fluxes at the 
centimeter scale of individual fractures could be many times the average values. The seepage into 
drifts depends on percolation flux. The key parameter is seepage threshold, the value below which 
seepage cannot occur. This value has been determined to be approximately 200 mm/yr (CRWMS 
M&O 1999d, p. 70). 
Percolating water that could penetrate a waste package and contact waste materials may pick up 
and transport radionuclides either in solution, suspension, or as colloids. The 
radionuclide-carrying water would then migrate toward engineered barriers such as backfill, 
where it could be retarded before reaching the near-field heated region of the rock surrounding the 
drift. Gaseous transport is also part of the conceptual model for radionuclide transport, but is not 
discussed further in this report because it is difficult to evaluate through natural analogs. 
Transport of dissolved or colloidal species depends on factors that include the water chemical 
composition, pH, Eh, and temperature; the type and distribution of mineral fracture coatings 
(especially sorptive minerals such as zeolites, clays, and Fe-Mn oxides); and the nature and extent 
of fracture-matrix interaction. 
Fracture flow has been shown to be the most likely mode of transport in the TSw, but water 
continuing downward would encounter different hydrologic conditions and flow properties when 
it reached the CHn (DOE 1998, p. 2-38). In some regions of the CHn it is expected that 
percolating water would contact both zeolitic and vitric tuffs. Flow in the zeolitic units would 
probably retard sorbing radionuclides such as Np, Cs, and Sr. In other areas, perched water zones 
resulting from low matrix permeabilities or hydrologic discontinuities may result in lateral 
diversion. Depending on the extent of the perched zone, water either may be laterally diverted for 
short distances before returning to the unsaturated zone or may continue laterally to the water 
table, bypassing the lower unsaturated zone. 
6.3 CRITERIA FOR SELECTION OF ANALOGS USED IN MODEL VALIDATION 
No single site will be a perfect analog to all ongoing and anticipated processes at Yucca Mountain. 
For this reason, focus is placed on sites having analogous processes rather than total system 
analogs. Given this caveat, however, it is still worthwhile to attempt to match as many features 
and characteristics as possible when identifying suitable analog sites. An ideal analog site to 
long-term radionuclide transport at Yucca Mountain would satisfy the following conditions: (1) 
have a known source term; (2) have a similar suite of radionuclides; (3) have a well-characterized 
data set; and (4) have similar geologic and hydrologic conditions. It is most useful if the analog 
has been in place for at least thousands of years, so that the results of long-term behavior are 
observable. The same criteria, slightly modified, can be used for geothermal analogs. There 
appears to be no perfect analog site for radionuclide transport at Yucca Mountain, partially 
because natural analog sites, with a few exceptions such as Oklo, in Gabon, provide little 
information about transport of neptunium and plutonium, two radionuclides of concern for Yucca 
Mountain. For this purpose, anthropogenic analogs are useful. However, in addition to using 
analogs for long-term predictions, models must be able to explain and match the transport times 
and pathways from contaminated sites that provide anthropogenic analogs, such as the Hanford 
Reservation, Washington; the Idaho National Engineering and Environmental Laboratory

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(INEEL), and the Nevada Test Site (NTS). Anthropogenic analog sites will be a challenge to 
constrain in models, as they contain numerous contaminated sites with poorly identified source 
terms, a complex mixture of radionuclides and other contaminants, and often occur in highly 
heterogeneous formations. 
6.4 METHODS 
The overall scientific approach taken in this report is that of reasoning by analogy. Analogy 
relates the likeness of a process or set of properties to a similar process or property set, either in 
another location or a different time frame. Analogy temporarily accepts a probable theory without 
absolute proof. For example, by applying models to processes operating in the geosphere in 
natural analog locations, their accuracy can be tested by either finding a negative instance to 
disprove the model or finding the fit is good in a particular instance, thus increasing confidence in 
the model. Natural analogs are also used to determine the range of applicability of a model. This 
report applies natural analogs to the UZ flow and transport model in three ways. First, information 
and data from suitable selected analogs reported in the literature are used to validate processes 
ongoing or anticipated at Yucca Mountain and to suggest means by which data from the analog 
sites may be used in future modeling efforts to bound ambient and thermally coupled processes at 
Yucca Mountain. Second, data from a fractured, unsaturated site in basalt are used to test the 
validity of the approach for modeling flow and transport processes, including fracture-matrix 
interactions, in the Yucca Mountain site-scale UZ flow and transport model (Section 6.5.1.1). 
Third, uranium-series data from an analog site in unsaturated rhyolitic tuff are used to build 
confidence in assumptions about radionuclide transport in fractures and matrix over hundreds of 
thousands of years (Section 6.5.2). In these ways, performance assessment will incorporate 
knowledge gained from natural analogs into process models that provide input to Yucca Mountain 
performance. 
Confidence may be built in models through a variety of different approaches, of which the 
comparison to natural analogs is only one. Other analysis/model reports may consider 
validation by application of field test data or by data set comparisons. These and other 
validation methods were not selected as approaches in this report because the specific purpose 
of this report was to investigate how the UZ flow and transport model may build increased 
confidence through application of natural analog information. 
6.5 RESULTS 
Although the Yucca Mountain data set is extensive, it is impossible to characterize 
deterministically flow and transport at all scales and under all anticipated environmental 
conditions. Analog sites, however, are able to provide data to indicate which flow and transport 
processes can be expected to be operative at Yucca Mountain over long periods of time and in 
some cases may bound those processes. Data from analog sites may also be used to build 
confidence in approaches to modeling flow and transport in fractured, unsaturated media. The 
following sections discuss some of the potential analog sites to Yucca Mountain for flow and 
transport processes. Section 6.5.1 discusses analogs to UZ infiltration, seepage and flow. Section 
6.5.2 discusses analogs to radionuclide transport. Section 6.5.3 discusses analogs to thermally 
coupled UZ processes.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 29 March 2000 
6.5.1An alogs to UZ Infiltration, Seepage, a nd Flow 
Section 6.5.1 examines analogs to UZ infiltration, seepage, and flow. Section 6.5.1.1 is a 
modeling study that uses data from Box Canyon, Idaho to build confidence in modeling 
approaches of UZ flow employed in Yucca Mountain models. Section 6.5.1.2 considers the 
analogous aspects of seepage and flow at Rainier Mesa to those at Yucca Mountain. Section 
6.5.1.3 addresses aspects of the Apache Leap site that may be used as an analog to processes 
occurring at Yucca Mountain. 
6.5.1.1 Box Canyon, Idaho 
The variably saturated fractured basalt hydrogeological system at Box Canyon, Idaho was 
proposed for this study in order to examine the applicability of conceptual and numerical 
modeling methodologies utilized at Yucca Mountain to similar but separate UZ hydrogeological 
systems. Verification of the applicability of these approaches at natural analog sites serves to 
substantiate their use as design and predictive tools for the Yucca Mountain nuclear repository. 
Box Canyon was chosen for the study because a considerable body of hydrologic data was 
available from studies at INEEL of unsaturated flow in fractured basalts. The studies had been 
conducted at scales ranging from core sample measurements (cm-scale) and meter-scale 
laboratory tests to field tests that covered tens of meters to a kilometer-scale aquifer pumping test. 
The Box Canyon tests were in the intermediate-scale range. 
All input and output files used during the numerical simulation of the Box Canyon site are listed 
in Attachment II. 
6.5.1.1.1 Background 
The Box Canyon site is located in the Eastern Snake River Plain near INEEL (see Figure 6-1) and 
is adjacent to the Big Lost River, which is a tributary of the Snake River. The Snake River Plain is 
primarily composed of fractured Quaternary basalt flows interbedded with sedimentary deposits. 
Sedimentary interbeds may separate basalt flow units that were formed at disparate times, and 
their thickness may range from a few centimeters to as much as 15 meters. Basalt flow units are 
comprised of a number of basalt flows arising from the same eruptive event. Individual basalt 
flows are from 3 m to 12 m thick and exhibit an extreme elongation in one direction giving them a 
finger or lenticular structure with a width ranging from 20 m to 60 m. The total basalt thickness in 
the Snake River Plain may exceed three kilometers (Whelan and Reed 1997; Knutson et al. 1993). 
The Box Canyon site is located on a basalt flow that is approximately 10 m to 12 m thick and also 
has a nearby cliff face exposure at the Big Lost River. Additional basalt flows underlie the upper 
basalt flow directly beneath the experimental site and the groundwater table is located at a depth 
of approximately 20 m.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 30 March 2000 
Figure 6-1. Map of East Snake River Plain Showing the Location of the Box Canyon Experimental 
Site (Faybishenko et al. 1999, Figure 2) 
Several infiltration experiments were conducted at the Box Canyon site to study the flow of water 
in the variably saturated fractured basalt (Faybishenko et al. 1998a, 1999). The first is called 96-1 
(twoweek ponded infiltration test) while the second consists of four separate infiltration events 
called 97-1, 97-2, 97-3 and 97-4 (2-to-4 day infiltration events). Instrumentation was used to 
delineate the subset of fractures that actively conducted the infiltrating water. The purpose of this 
study was to construct and calibrate a numerical model to simulate the observed infiltration 
behavior of water at the Box Canyon site. The methodology adopted to simulate the Box Canyon 
site was based on the dual-permeability numerical approach used to characterize variably 
saturated flow at Yucca Mountain (Bandurraga and Bodvarsson 1999). Hydrogeological 
parameters used to calibrate the Box Canyon model could then be used to substantiate analogous 
parameters obtained during calibration of the Yucca Mountain site. Our investigation involved 
identifying physical processes and calibrating parameters controlling the observed infiltration of 
water at the Box Canyon site. 
6.5.1.1.2 Geological Model Conceptualization 
Conceptualization of the geological model for the Box Canyon site follows directly from 
Faybishenko et al. (1999). The site consists of layered basalt flows containing horizontal as well 
as vertical columnar fractures resulting from cooling of the basalt. The water table at the Box 
Canyon experimental site is approximately 20 m below the ground surface. Field data at the Box 
Canyon site consisted of monitoring pneumatic and infiltration tests almost entirely within the 
upper basalt flow. The elevation of the ground surface at the site is shown on Figure 6-2a, along 
S 
n 
a 
k 
e 
R 
i 
v 
e 
r 
P 
l 
a 
i 
n 
Palisades 
Reservoir 
Pocatello 
American 
Falls 
Reservoir Lake 
Walcott 
Twin 
Falls 
K i n g 
H i l l 
Idaho 
National 
Engineering 
Laboratory 
Box 
Canyon 
site 
R 
i 
v 
e 
r 
Sn 
a 
k 
e 
Jackson 
Lake 
S 
n 
a 
k 
e 
R 
i 
v 
e 
r 
M 
o 
n 
t 
a 
n 
a 
I 
d 
a 
h 
o 
I d a h o 
W y o m i n g 
I d a h o 
U t a h N e v a d a 
0 20 40 Miles 
0 20 40 Kilometers 
Idaho 
Wyoming 
Utah Nevada 
Montana

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 31 March 2000 
with the surface location of all instrumented vertical and slanted boreholes. The bottom of the 
upper basalt is identified by the presence of a first rubble zone observed in core logs and open 
borehole measurements (Faybishenko et al. 1998b). The top elevation of this rubble zone is 
shown on Figure 6-2b, resulting in an average thickness of the upper basalt flow of 12 m. The box 
outline indicates the perimeter of the infiltration pond used to contain the ponded water at the 
ground surface. 
(Table 6-3 in DTN: LB990930123122.001) 
Figure 6-2. Elevation of (a) Ground Surface and (b) Top of Rubble Zone with All Well Locations and 
Perimeter of the Infiltration Pond 
50 55 60 65 70 
55 
60 
65 
70 
1599.8 
1599.7 
1599.6 
1599.5 
1599.4 
1599.3 
1599.2 
1599.1 
Elevation 
(m) 
Easting (m) 
Northing (m) 
(a) 
R-3 
R-6 
R-1 
R-5 
II-6 
S-4 
T-3 
S-3 
R-4
T-2 
R-2 
I-5 
II-8 
II-7 
T-4 
I-4 
II-4 
E-4 
E-3
E-2 
E-1 
I-3 
II-5 
T-5 
S-1
S-2 
I-2 
T-10 T-9 
T-8a 
I-1 T-8 
T-6 
T-7 
T-1 
II-3 
II-1 
II-2 
50 55 60 65 70 
55 
60 
65 
70 
1589.5 
1589 
1588.5 
1588 
1587.5 
1587 
1586.5 
1586 
1585.5 
1585 
1584.5 
(b) 
Easting (m) 
Elevation 
(m) 
Northing (m)

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 RE V00 32March 2000 
Grossenbacher and Faybishenko (1995) mapped horizontal and vertical columnar basalt fractures 
along an outcrop near the Box Canyon experimental site. They observed that the vertical fracture 
spacing increased from ground surface to a dimensionless depth of 0.6. The dimensionless depth 
is defined as the depth from the ground surface divided by the thickness of the upper basalt flow. 
The vertical fracture spacing then decreased from the dimensionless depth of 0.6 to the bottom of 
the basalt flow. Basalt columns separated by vertical fractures were formed as the basalt cooled 
more rapidly from the ground surface downward than upward. The smaller fracture spacing in the 
upper part of the basalt flow resulted from larger temperature gradients near the surface than those 
at the lower part of the flow. Columnar fractures originating from the top and bottom of the basalt 
reached an identical spacing where the two cooling fronts met at the dimensionless depth of 0.6. 
The horizontal spacing of vertical fractures (DH) as a function of dimensionless depth was used to 
subdivide the upper basalt flow into five zones extending from the ground surface to the bottom, 
in the following intervals: 0 to 0.2, 0.2 to 0.4, 0.4 to 0.6, 0.6 to 0.8 and 0.8 to 1.0. The horizontal 
and vertical fracture spacing, DH and DV, for each zone are provided in Table 6-2. 
Table 6-2. Fracture and Matrix Properties Used in Box Canyon Study 
DTN: LB990930123122.001 
Parameters which vary within each zone for the fracture continuum nodes include the horizontal 
and vertical fracture spacing (DH and DV, respectively), the components of the permeability tensor 
and the resulting aperture (kx, ky, kz and b, respectively), porosity f and a related scaling factor, 
van Genuchten capillary-pressure and relative permeability function parameters a and m, and the 
fracture-matrix interfacial area scaling factor Afm. Similar parameters for the matrix continuum 
nodes include the permeability, porosity and van Genuchten parameters. The source, derivation 
or calibration method used to obtain these parameters is described in the following sections where 
relevant and are introduced in Table 6-2 for brevity. 
The focus of the conceptual geological model is to address issues related to the geometry of fast 
preferential flow paths of infiltrating water in the basalt hydrogeological system. Therefore, we 
identified fractures that actively conducted water during the infiltration tests and then used these 
data to determine an interconnected fracture network. This involved examining hydrogeological 
data collected by Faybishenko et al. (1998a, 1999) for the 96-1 and 97-1 to 97-4 infiltration tests 
Zone Aperture Porosity f scale Afm scale 
DH DV b kx ky kz f a m factor factor 
(m) (m) (m) (m2) (m2
) (m2
) (-) (Pa-1) (-) (-) (-) 
0.0 - 0.2 1.0 1.0 8.54E-05 1.04E-13 1.04E-13 1.04E-13 2.56E-04 5.00E-04 0.5 50.0 0.01 
0.2 - 0.4 2.0 1.0 1.48E-04 4.05E-13 4.05E-13 2.70E-13 2.96E-04 5.00E-04 0.5 50.0 0.01 
0.4 - 0.6 4.0 1.0 1.57E-04 4.03E-13 4.03E-13 1.61E-13 2.36E-04 5.00E-04 0.5 50.0 0.01 
0.6 - 0.8 4.0 1.0 1.22E-04 1.89E-13 1.89E-13 7.57E-14 1.83E-04 5.00E-04 0.5 50.0 0.01 
0.8 - 1.0 2.0 1.0 2.09E-04 1.14E-12 1.14E-12 7.61E-13 4.18E-04 5.00E-04 0.5 50.0 0.01 
rubble zone 0.1 0.1 8.59E-04 1.06E-09 1.06E-09 1.06E-09 2.58E-02 5.00E-04 0.5 5.0 0.01 
lower basalt 2.0 1.0 1.28E-03 2.62E-10 2.62E-10 1.75E-10 2.56E-03 5.00E-04 0.5 5.0 0.01 
0.0 - 0.2 1.00E-14 1.00E-14 1.00E-14 0.20 5.00E-05 0.25 
0.2 - 0.4 1.00E-14 1.00E-14 1.00E-14 0.20 5.00E-05 0.25 
0.4 - 0.6 1.00E-14 1.00E-14 1.00E-14 0.20 5.00E-05 0.25 
0.6 - 0.8 1.00E-14 1.00E-14 1.00E-14 0.20 5.00E-05 0.25 
0.8 - 1.0 1.00E-14 1.00E-14 1.00E-14 0.20 5.00E-05 0.25 
rubble zone 1.00E-14 1.00E-14 1.00E-14 0.20 5.00E-05 0.25 
lower basalt 1.00E-14 1.00E-14 1.00E-14 0.20 5.00E-05 0.25 
van Genuchten Fracture Spacing Permeability 
Matrix Properties 
Zonal Fracture Properties 
Zonal

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 33 March 2000 
to determine whether fractures that actively conducted water could be observed as they 
intersected a borehole. All such features are listed on Table 6-3 and were inferred from 
examination of bromide samples, lysimeter, tensiometer, time domain reflectometry (TDR) probe 
and electrical resistivity (ER) probe data collected during the 96-1 infiltration test as well as 
additional ER probe and bromide sample data collected during the 97-1 to 97-4 infiltration tests. 
The location in plan view of these observation points is provided on Figure 6-3. It is important to 
note that in terms of constructing the conceptual geological model, these data were used to infer 
only the structure of the fracture network and not any hydrogeological properties associated with 
it.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 34 March 2000 
Table 6-3. Location of Borehole Intersections with Active Water-Conducting Fractures 
DTN: LB990930123122.001 
observation vertical vertical depth along easting northing elevation elev. of ground dim. data 
point depth depth borehole (m) (m) (m) rubble elev. depth source 
(ft) (m) (m) zone (m) (m) (-) 
S-1-1 2.00 0.61 0.70 62.12 64.60 1598.97 1588.75 1599.60 0.06 g 
a 97 ER Probe 
S-1-2 6.00 1.83 2.11 61.75 64.00 1597.75 1588.75 1599.70 0.18 a, g 
b 97 Bromide Sample 
S-1-3 10.00 3.05 3.52 61.39 63.39 1596.53 1588.75 1599.70 0.29 a 
c 96 Bromide Sample 
S-1-4 13.60 4.15 4.79 61.06 62.85 1595.43 1588.75 1599.70 0.39 a 
d 96 Lysimeter 
e 96 Tensiometer 
S-2-1 3.00 0.91 1.06 62.98 65.68 1598.60 1588.75 1599.52 0.08 a 
f 96 TDR Probe 
g 96 ER Probe 
S-3-1 2.50 0.76 0.88 64.35 67.74 1598.80 1588.25 1599.50 0.06 a, c, g 
S-3-2 6.50 1.98 2.29 63.94 67.16 1597.58 1588.50 1599.50 0.17 a 
S-3-3 11.00 3.35 3.87 63.49 66.51 1596.21 1588.75 1599.50 0.31 a, g 
S-3-4 26.50 8.08 9.33 61.92 64.28 1591.49 1588.75 1599.60 0.75 g 
S-4-1 3.00 0.91 1.06 66.23 71.35 1598.56 1588.25 1599.48 0.08 a 
S-4-2 48.00 14.63 16.89 62.11 64.58 1584.85 1588.75 1599.48 1.36 g 
E-1-1 4.90 1.49 2.26 59.12 62.98 1598.18 1588.50 1599.67 0.13 b, d 
E-1-2 8.50 2.59 3.93 60.02 63.85 1597.08 1588.25 1599.70 0.23 d 
E-1-3 30.40 9.27 14.05 65.50 69.14 1590.40 1587.50 1599.50 0.76 d 
E-1-4 38.20 11.64 17.66 67.45 71.02 1588.03 1588.25 1599.40 1.02 d 
E-2-1 23.60 7.19 9.39 60.96 65.70 1592.50 1588.25 1599.60 0.63 d 
E-2-2 38.10 11.61 15.16 63.21 68.65 1588.08 1588.25 1599.70 1.02 b, d 
E-3-1 18.00 5.49 6.70 58.60 63.00 1594.15 1588.50 1599.60 0.49 b, d 
E-3-2 24.00 7.32 8.93 59.40 64.00 1592.32 1588.00 1599.70 0.63 b, d 
E-4-1 12.00 3.66 4.14 57.09 60.74 1595.97 1587.50 1599.60 0.30 b 
E-4-2 20.00 6.10 6.90 57.88 61.77 1593.53 1588.00 1599.60 0.52 d 
E-4-3 25.00 7.62 8.63 58.37 62.41 1592.01 1588.25 1599.60 0.67 d 
I-1-1 1.00 0.30 0.30 58.90 64.40 1599.34 1588.06 1599.64 0.03 b, c, d 
I-1-2 5.00 1.52 1.52 58.90 64.40 1598.12 1588.06 1599.64 0.13 b, c, d 
I-1-3 10.00 3.05 3.05 58.90 64.40 1596.59 1588.06 1599.64 0.26 b, d 
I-1-4 15.00 4.57 4.57 58.90 64.40 1595.07 1588.06 1599.64 0.39 d 
I-1-5 20.00 6.10 6.10 58.90 64.40 1593.54 1588.06 1599.64 0.53 b, d 
I-1-6 27.89 8.50 8.50 58.90 64.40 1591.14 1588.06 1599.64 0.73 b, d 
I-1-7 33.00 10.06 10.06 58.90 64.40 1589.58 1588.06 1599.64 0.87 b, d 
I-2-1 1.00 0.30 0.30 60.80 67.90 1599.40 1587.81 1599.70 0.03 b, d 
I-2-2 5.00 1.52 1.52 60.80 67.90 1598.18 1587.81 1599.70 0.13 b, d 
I-2-3 10.00 3.05 3.05 60.80 67.90 1596.65 1587.81 1599.70 0.26 b, c, d 
I-2-4 14.00 4.27 4.27 60.80 67.90 1595.43 1587.81 1599.70 0.36 c, d 
I-2-5 20.00 6.10 6.10 60.80 67.90 1593.60 1587.81 1599.70 0.51 b 
I-3-1 1.00 0.30 0.30 60.90 61.00 1599.35 1588.98 1599.65 0.03 b, c, d 
I-3-2 5.00 1.52 1.52 60.90 61.00 1598.13 1588.98 1599.65 0.14 b, d 
T-2-1 2.00 0.61 0.61 67.00 64.50 1598.89 1589.00 1599.50 0.06 c, d, e 
T-2-2 6.00 1.83 1.83 67.00 64.50 1597.67 1589.00 1599.50 0.17 b, c, d, e 
T-2-3 10.00 3.05 3.05 67.00 64.50 1596.45 1589.00 1599.50 0.29 d, e 
T-3-1 2.00 0.61 0.61 63.30 69.20 1599.14 1587.75 1599.75 0.05 d, e, f 
T-3-2 6.00 1.83 1.83 63.30 69.20 1597.92 1587.75 1599.75 0.15 e 
T-3-3 15.00 4.57 4.57 63.30 69.20 1595.18 1587.75 1599.75 0.38 b 
T-4-1 2.00 0.61 0.61 63.10 58.20 1598.95 1589.75 1599.56 0.06 b, c, d, e, f 
T-4-2 5.50 1.68 1.68 63.10 58.20 1597.88 1589.75 1599.56 0.17 e 
T-4-3 9.00 2.74 2.74 63.10 58.20 1596.82 1589.75 1599.56 0.28 b, c, d, e 
T-4-4 14.00 4.27 4.27 63.10 58.20 1595.29 1589.75 1599.56 0.43 b, c, d 
T-4-5 19.00 5.79 5.79 63.10 58.20 1593.77 1589.75 1599.56 0.59 b, c, d

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 35 March 2000 
(Table 6-3 in DTN: LB990930123122.001) 
Figure 6-3. Plan View of the Location of Borehole Intersections with Active Water-Conducting 
Fractures. The Red Symbols Indicate the Location of the Top of Each Borehole While the 
Green Symbols Indicate the Location, in Plan view, of the Observed Flow Features in the 
Slanted Boreholes. Symbol Shape is Used to Identify the Different Borehole Groups 
Identified by Their Name (Faybishenko et al, 1998a). 
Hydrogeological characterization of the matrix was conducted by Knutson et al. (1990) who 
measured the permeability and porosity of core samples. These data are provided in Table 6-4. 
Samples with high porosities, obtained from vesicular regions of the matrix, yielded permeability 
values greater than 110-12 m2 and were not included in this table. The arithmetic mean porosity 
of the core samples was 19.2% and the geometric mean permeability was 2.2410-15 m2. This 
permeability is expected to be biased towards the impermeable regions of the basalt because the 
permeability measurements from the vesicular zone were not included. 
55 60 65 70 
60 
65 
70 
Easting (m) 
Northing (m) 
S-4 
S-4-1 E-1-4 
E-1-3 
S-3 
S-3-1 
S-3-2 
S-3-3 
S-2 
S-2-1 
S-1 
S-1-1 
S-3-4 
S-1-2 
T-2 
T-3 
E-2-2 
I-2 
T-9
E-2-1
T-5 
II-5 
I-3 
T-4 
E-4 
E-3
E-4-1 
E-2
E-1 E-4-2 
E-4-3 
E-1-1 
S-1-4 
S-1-3 
T-7
T-6
E-1-2 
T-8 
E-3-2 
I-1 
E-3-1

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 36 March 2000 
Table 6-4. Matrix Porosity and Permeability Measurements from Core Samples 
DTN: LB990930123122.001 
sample porosity permeability 
(%) (m2) 
A-1 30.7 9.48E-14 
A-2 23.5 3.50E-15 
A-3 19.1 3.20E-15 
A-4 15.3 8.00E-16 
A-5 11.3 2.40E-15 
A-6 23.1 2.00E-16 
A-7 22.0 2.10E-15 
A-10 23.5 7.40E-14 
A-12 20.5 1.60E-15 
A-18 26.0 - 
A-19 12.0 5.30E-15 
A-20 35.4 - 
A-23 14.6 - 
A-25 38.4 - 
A-27 25.9 9.80E-15 
A-30 16.2 5.00E-16 
A-34 21.0 1.00E-16 
B-1 10.6 1.28E-14 
B-3 15.2 4.10E-15 
B-5 14.9 3.14E-14 
B-7 16.2 4.00E-16 
B-9 26.6 2.60E-15 
B-11 13.9 9.40E-15 
B-12 25.5 1.00E-16 
B-15 12.6 5.00E-16 
C-5 14.8 1.10E-15 
C-6 17.4 2.60E-15 
C-15 9.9 7.00E-16 
C-24 12.6 8.90E-15 
C-38 12.4 4.30E-15 
D-1 26.5 1.30E-15 
D-2 12.8 1.80E-14 
D-5 18.8 4.00E-15 
D-6 5.2 3.00E-16 
D-8 18.8 4.00E-15 
D-13 19.0 1.80E-15 
D-16 10.5 2.20E-15 
D-17 26.3 - 
D-26 11.8 5.40E-15 
D-27 12.0 1.01E-14 
D-29 17.5 1.00E-16 
D-30 10.0 1.00E-16 
D-31 18.6 4.00E-16 
D-32 33.1 - 
E-2 12.8 1.70E-15 
E-4 24.0 3.20E-15 
E-6 12.8 1.70E-15 
E-9 22.4 9.00E-15 
E-10 22.4 9.20E-15 
E-30 43.2 - 
mean 19.2 2.24E-15

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 37 March 2000 
6.5.1.1.3 Numerical Model Conceptualization 
Application of dual-permeability models to simulate fracture/matrix flow of infiltrating water in 
the variably saturated tuffs at Yucca Mountain has evolved through various conceptual stages. In 
general, they involve the application of various methodologies to reduce the interfacial area 
between the fracture and matrix continua and hence the degree to which they interact. 
Furthermore, the matrix continuum may be represented as a single node or as multiple 
interconnected nodes to spatially resolve the imbibition of water from the fracture continuum. 
Bandurraga and Bodvarsson (1999) describe the initial application of a dual-permeability model 
for Yucca Mountain where the matrix continuum is represented using a single node and the 
fracture/matrix interfacial area is reduced by a constant factor ranging from 0.0005 to 0.05. 
Doughty (1999) performed a sensitivity analysis using various procedures to scale the interfacial 
area between the fracture and matrix continua depending on the constant factor approach, the 
relative permeability of the liquid, and the saturation of the infiltrating liquid. Alternative 
representations of the matrix continuum were also included. Liu et al. (1998) developed an 
active fracture representation where a single parameter is used to estimate the fraction of 
fractures which actively conduct water, the spacing between these fractures, and the 
fracture/matrix interfacial area reduction factor. This methodology is based on relating the 
saturation of the infiltrating water to the fraction of active water-conducting fractures, the water 
capillary pressure and relative permeability-saturation relationships, and the flux of water 
between the fracture and matrix continua. All of this work has focused on calibrating the Yucca 
Mountain UZ flow and transport model to measured steady-state water saturation and capillary 
pressure profiles resulting from infiltration of long-term averaged precipitation over the site. We 
applied the dual-permeability approach at Box Canyon to simulate the transient migration of 
water from short-term infiltration events. Furthermore, extensive field work at the Box Canyon 
site focused on delineating fractures which actively conducted the infiltrating water. Given the 
significant decrease in scale from the Yucca Mountain to the Box Canyon model, the transient 
nature of the infiltration events, and the subsequent characterization of active water-conducting 
fractures, we adopted the initial implementation of the dual-permeability model from the Yucca 
Mountain studies. Validation of this preliminary approach at Box Canyon would provide the 
foundation for extending subsequent work from Yucca Mountain. 
Calibration of the Box Canyon model was performed in two steps, using air-injection and 
infiltration test data. The conceptual geological model was used to develop a numerical model to 
simulate the physics of water- and gas-phase advection through the fractured basalt at Box 
Canyon. The numerical modeling effort was conducted using TOUGH2 codes (Pruess 1991) with 
the EOS3 module, which involves both mobile water and gas phases. This was necessary because 
calibration of the model involved the analysis of both pneumatic and infiltration test data. 
The fracture-matrix system of the basalt was simulated using a dual-permeability grid in an 
analogous manner to that used to simulate the site-scale variably saturated groundwater flow field 
at Yucca Mountain. In the dual-permeability modeling approach, two separate nodes occupy the 
same geometric volume within the grid, with one node representing the matrix continuum and the 
other representing the fracture continuum. Both the matrix and fracture nodes are interconnected 
at each geometric volume within the grid where they overlap. Furthermore, the fracture 
continuum nodes are connected to adjacent fracture continuum nodes, while the matrix continuum 
nodes are connected to adjacent matrix continuum nodes. A three-dimensional visualization of the

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 38 March 2000 
structure of the model, including the zonation of the upper basalt and the inclusion of the rubble 
zone, as well as a portion of the lower basalt, is shown in Figure 6-4. Two separate views of the 
model are shown to illustrate the variable thickness of the upper basalt flow. In the figure, the 
arrows indicate the orientation of the views. The model was discretized using a grid of 
23  21  21 nodes of dimension 1.0 m  1.0 m  1.0 m in the x-, y- and z-dimensions, 
respectively, for each of the matrix and fracture continua nodes. Connections between nodes 
follow a simple seven-point lattice, with both fracture and matrix continua nodes connected to 
each other as well as to the six adjacent like nodes. The discretization was chosen to represent the 
zonal structure of the upper basalt flow and to resolve simulated water saturation profiles during 
the infiltration experiments. Furthermore, the lateral and vertical dimensions of the model were 
chosen to contain the full three-dimensional infiltration front extending from beneath the pond 
(see Figure 6-2) within the entire upper basalt flow without the interference from bounding 
conditions. This discretization yielded a combined total of 20286 matrix and fracture continua 
nodes which permitted reasonable simulation times of the model for calibration purposes. 
DTN: LB990930123122.002 
Figure 6-4. Two Separate Views of the Numerical Model with Zonal Information 
Based on the observations of active water flow features given in Table 6-3, a conceptual fracture 
network was constructed and mapped onto a plan view of the mesh, as shown in Figure 6-5. 
Fractures above a dimensionless depth of 0.6 are assumed to extend vertically downward from the 
ground surface. Active water flow features observed below a dimensionless depth of 0.6 are 
assumed to result from fractures extending from the bottom of the model upward. Fractures are 
assumed not to cross the dimensionless depth of 0.6 where the two cooling fronts intersected. The 
orientation of the fractures is assumed north-south, east-west to coincide with the orientation of 
the mesh. This orientation was chosen because it is on an approximate 45-degree angle with the E 
and S series of slanted boreholes and represents the fracture orientation angle that would 
maximize the probability of these boreholes intersecting a fracture. The fracture pattern was also 
selected so that two neighboring fractures within the same dimensionless depths were on average 
1580 
1585 
1590 
1595 
50 
55 
60 
65 
70 
55 
60 
65 
70 
Easting (m) Northing (m) 
1580 
1585 
1590 
1595 
1600 
50 
55 
60 
65 
70 
55 
60 
65 
70 Easting (m) Northing (m) 
Elevation (m) 
0 - 0.2 
0.4 - 0.6 
0.6 - 0.8 
rubble zone 
lower basalt 
0.2 - 0.4 
0.8 - 1.0

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 39 March 2000 
separated by a distance equal to the fracture spacing. Furthermore, the length of a fracture 
extending to either side of the actual observation point was also equivalent to the fracture spacing 
at the dimensionless depth of the observation point. 
(Table 6-3 in DTN: LB990930123122.001) 
Figure 6-5. Conceptual Distribution of Fractures Determined to Actively Conduct Infiltrating Water as a 
Function of Dimensionless Depth 
The fracture network shown in Figure 6-5 was used to condition the permeability kfi (m2) and 
porosity ffi () of the fracture continuum nodes which are calculated from the fracture aperture bi 
(m) of node i as: 
(Eq. 1) 
(Eq. 2) 
(Eq. 3) 
(Eq. 4) 
where kxfi, kyfi and kzfi are diagonal components of the fracture continuum permeability tensor 
and xi (), yi (), and zi () are weighting factors for node i in the x-, y- and z- directions, 
50 55 60 65 70 
55 
60 
65 
70 
75 
Easting (m) 
Northing (m) 
dimensionless 
depth 
0 - 0.4 
0 - 0.6 
1 - 0.6 
1 - 0.8 
Vi 
i 
Hi 
i 
xi xfi D 
b 
D 
b 
k 
12 12 
3 3 
+ =  
Vi 
i 
Hi 
i 
yi yfi D 
b 
D 
b 
k 
12 12 
3 3 
+ =  
Hi 
i 
zi zfi D 
b 
k 
12 
3 
 = 
Vi 
i 
Hi 
i 
yi 
Hi 
i 
xi fi D
b 
D
b 
D
b + + =   f

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 40 March 2000 
respectively. Derivation of the fracture continuum permeabilities is provided in Attachment IV. 
Weighting factors were only applied to terms depending on the horizontal fracture spacing and not 
on the vertical fracture spacing. 
In the context of fracture continuum parameters, the  weighting factors were used to increase the 
permeability and porosity of nodes where flow was actually observed to occur relative to the 
unconditioned background nodes. In particular, the  weighting factor of these nodes was chosen 
so that a single fracture exists at the node in the orientation shown on Figure 6-5. The derivation 
of the appropriate  weighting factor to condition these nodes is given in Attachment IV. 
Conditioning these nodes in this manner is equivalent to replacing the fracture continuum 
permeability and porosity calculated using Equations 1 through 4 with that from a discrete 
fracture. All unconditioned nodes received weighting factors of x = y = 1.0 and z = x + y. 
The horizontal fracture spacing was always greater than the grid discretization except for a 
dimensionless depth of 0.0  0.2 where they were equal. Therefore, the fracture continuum 
permeability and porosity for the background unconditioned nodes was always less than that for 
nodes where observed water flow features occurred. This is equivalent to stating that background 
unconditioned nodes only conduct a fraction of infiltrating water from a single fracture that is 
proportional to the node discretization divided by the fracture spacing. To prevent biasing nodes 
from increasing the net infiltration through the model, but rather to promote preferential channel 
flow through observed fracture flow features, the weighting factor of neighboring nodes was 
decreased. Hence, conservation of net infiltration flux was enforced by constraining the 
cumulative sum of the weighting factor for all biased nodes resulting from the observed flow 
feature to be identical to that of unconditioned nodes. Figures 6-6 to 6-9 show  weighting factors 
for fractures extending to the various dimensionless depths. Weighting factors were not estimated 
for dimensionless depth interval 0.0  0.2 because the grid discretization was equal to the 
horizontal fracture spacing, implying that each fracture continuum node contained one discrete 
fracture.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 41 March 2000 
DTN: LB990930123122.002 
Figure 6-6. Fracture Continuum Weighting Factors (a) x, (b) y, and (c) z for Dimensionless Depth 
Interval of 0.2 to 0.4 
Northing (m) Northing (m) 
weighting factor 
multiplier for 
fracture properties 
50 55 60 65 70 
55 
60 
65 
70 4
3.75 
3.5 
3.25 
3
2.75 
2.5 
2.25 
2
1.75 
1.5 
1.25 
1
0.75 
0.5 
0.25 
0 
Easting (m) 
50 55 60 65 70 
55 
60 
65 
70 
(b) 
Easting (m) 
50 55 60 65 70 
55 
60 
65 
70 
(a) 
(c) 
Easting (m) 
Northing (m)

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV 00 42March 2000 
DTN: LB990930123122.002 
Figure 6-7. Fracture Continuum Weighting Factors (a) x, (b) y 
, and (c) z for Dimensionless Depth 
Interval of 0.4 to 0.6 
Northing (m) Northing (m) 
weighting factor 
multiplier for 
fracture properties 
50 55 60 65 70 
55 
60 
65 
70 8
7.5 
7
6.5 
6
5.5 
5
4.5 
4
3.5 
3
2.5 
2
1.5 
1
0.5 
0 
Easting (m) 
50 55 60 65 70 
55 
60 
65 
70 
(b) 
Easting (m) 
50 55 60 65 70 
55 
60 
65 
70 
(a) 
(c) 
Easting (m) 
Northing (m)

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 43 March 2000 
DTN: LB990930123122.002 
Figure 6-8. Fracture Continuum Weighting Factors (a) x, (b) y, and (c) z for Dimensionless Depth 
Interval of 0.6 to 0.8 
Northing (m) Northing (m) 
weighting factor 
multiplier for 
fracture properties 
50 55 60 65 70 
55 
60 
65 
70 8
7.5 
7
6.5 
6
5.5 
5
4.5 
4
3.5 
3
2.5 
2
1.5 
1
0.5 
0 
Easting (m) 
50 55 60 65 70 
55 
60 
65 
70 
(a) 
(c) 
Easting (m) 
Northing (m) 
50 55 60 65 70 
55 
60 
65 
70 
(b) 
Easting (m)

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 44 March 2000 
DTN: LB990930123122.002 
Figure 6-9. Fracture Continuum Weighting Factors (a) x, (b) y, and (c) z for Dimensionless Depth 
Interval of 0.8 to 1.0 
Northing (m) Northing (m) 
weighting factor 
multiplier for 
fracture properties 
50 55 60 65 70 
55 
60 
65 
70 4
3.75 
3.5 
3.25 
3
2.75 
2.5 
2.25 
2
1.75 
1.5 
1.25 
1
0.75 
0.5 
0.25 
0 
Easting (m) 
50 55 60 65 70 
55 
60 
65 
70 
(a) 
(c) 
Easting (m) 
Northing (m) 
50 55 60 65 70 
55 
60 
65 
70 
(b) 
Easting (m)

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 45 March 2000 
Flow of water and gas occurs between the fracture and matrix continua according to the mass 
conservation laws discretized by TOUGH2. Specifically, the interfacial area between the fracture 
and matrix continua through which the water and gas flow is given as: 
(Eq. 5) 
where .xi = .yi = .zi = 1.0 m, which represents the size of node i in the x-, y- and z-directions. 
This formulation is consistent with that used in the dual-permeability simulations of the UZ 
site-scale Yucca Mountain model. 
6.5.1.1.4 Pneumatic Test Analysis 
Pneumatic tests were conducted at the Box Canyon site to assess the permeability of the basalt. 
These tests consisted of air being injected into approximately three-meter packer intervals within 
slanted boreholes S-3 and S-4 as well as the vertical borehole II-5. These wells are all located 
within close lateral proximity of one another as shown on Figure 6-2a. The intent of these tests 
was to delineate vertical variations in the permeability of the upper basalt flow. The pneumatic 
tests consisted of injecting air at a constant rate within the packer interval and measuring the 
steady-state pressure response within the packer interval as well as in neighboring boreholes. This 
methodology has also been used extensively to characterize the permeability of the 
interconnected fracture network at Yucca Mountain (Huang et al. 1999). See Assumption #5 in 
Section 5 of this report. The injected air is assumed to flow entirely through the fracture network 
rather than through the matrix, given that air is a nonwetting phase in an air-water system and 
prefers to reside in the larger pore spaces of the fractures. In contrast, water preferentially resides 
in the matrix with saturations ranging from 0.55 to 0.8 within the model. This assumption was 
necessary to allow the pneumatic tests to estimate fracture continuum permeability as a single 
unknown property without any a priori assumptions regarding additional parameters involved in 
fracture/matrix flow to be calibrated using the infiltration arrival times. Although this assumption 
appears extreme, the complete and final Box Canyon model including matrix continuum nodes 
was used to resimulate selected pneumatic tests yielding similar pressure response results, 
implying that the assumption was justified. Details concerning the pneumatic tests conducted at 
Box Canyon can be found in Benito et al. (1998). 
The pneumatic tests were simulated using the three-dimensional model in order to calibrate the 
permeability of the fracture continuum nodes. To calibrate the model, we used only steady-state 
pressure responses within the injection intervals. Matching pressure responses in adjacent 
boreholes could refine calibration of the fracture continuum permeabilities. The spatial location of 
each injection interval is given under the section Centroid of Injection Interval while the 
specific fracture continuum node within which injection was performed is given under section 
Node of Table 6-5. The applied injection rate and steady-state pressure response measured in 
the field are provided under section Field Data of Table 6-5. An initial estimate of fracture 
permeability surrounding the injection interval for each pneumatic test was obtained using an 
analytical solution derived by Baehr and Hult (1991) (see p. 2611, Eq. 56). These permeabilities 
are listed under the ktest column of Table 6-5. 
. .. 
. 
. .
.
. . 
. . + 
. 
. . + 
. 
. . = 
Vi
i 
i i 
Hi
i 
i i yi 
Hi
i 
i i xi ifm D
z 
y x 
D
y 
z x 
D
x 
z y A   2

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 46 March 2000 
INTENTIONALLY LEFT BLANK

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 47 March 2000 
Table 6-5. Fracture Permeability Calibration Results from the Analysis of the Pneumatic Test Data 
DTN: LB990930123122.001 
Test Zone 
ID Easting Northing Elevation Qinj .P ktest kmodel x y z kmean b kmean b Pfield Pmodel .Presidual %error 
(m) (m) (m) ix iy iz name (kg/s) (Pa) (m2) (m2) (m2) (m) (m2) (m) (Pa) (Pa) (Pa) 
1 0 - 0.2 63.76 66.90 1597.02 14 14 3 c1414 1.98E-03 35600 3.96E-14 1.58E-13 1.00 1.00 2.00 1.58E-13 9.83E-05 135387 136840 -1453 -1.07 
2 0 - 0.2 65.79 70.63 1597.10 16 18 3 c1618 3.96E-03 114100 1.70E-14 6.78E-14 1.00 1.00 2.00 6.78E-14 7.41E-05 1.04E-13 8.54E-05 213887 202730 11157 5.22 
3 0.2 - 0.4 62.40 62.90 1596.09 13 10 4 d1310 5.95E-03 52200 1.16E-13 4.66E-13 0.50 0.50 1.00 4.66E-13 1.65E-04 151998 149230 2768 1.82 
4 0.2 - 0.4 65.53 70.21 1596.25 16 18 4 d1618 3.96E-03 171900 1.44E-14 5.76E-14 1.00 1.00 2.00 5.76E-14 7.73E-05 271698 209890 61808 22.75 
5 0.2 - 0.4 62.40 62.90 1595.18 13 10 5 e1310 5.95E-03 223550 1.95E-14 7.79E-14 0.50 0.50 1.00 7.79E-14 9.08E-05 323360 227940 95420 29.51 
6 0.2 - 0.4 63.32 66.28 1595.71 14 14 5 e1414 3.96E-03 49680 9.34E-14 3.74E-13 0.75 2.00 2.75 3.74E-13 1.39E-04 149490 135340 14150 9.47 
7a 0.2 - 0.4 65.30 69.82 1595.47 16 17 5 e1617 3.96E-03 1438 4.40E-12 1.76E-11 1.00 1.00 2.00 1.40E-11 4.82E-04 4.06E-13 1.48E-04 101248 112740 -11492 -11.35 
7b 65.30 69.82 1595.47 16 17 5 8.32E-03 4670 2.79E-12 1.12E-11 104480 125190 -20710 -19.82 
8 0.4 - 0.6 62.40 62.90 1594.27 13 10 6 f1310 5.95E-03 5593 1.95E-12 3.91E-12 1.00 1.00 2.00 3.91E-12 3.35E-04 105414 126370 -20956 -19.88 
9 0.4 - 0.6 62.88 65.65 1594.38 13 13 6 f1313 3.96E-03 69800 7.58E-14 1.52E-13 0.75 1.00 1.75 1.52E-13 1.14E-04 169621 169300 321 0.19 
10 0.4 - 0.6 64.90 69.17 1594.14 15 17 6 f1517 3.57E-03 327000 7.09E-15 1.42E-14 1.00 1.00 2.00 1.42E-14 5.14E-05 426821 346040 80781 18.93 
11 0.4 - 0.6 65.06 69.43 1594.67 16 17 6 f1617 3.96E-03 1728 4.18E-12 8.36E-12 1.00 1.00 2.00 8.36E-12 4.31E-04 101549 114900 -13351 -13.15 
12a 0.4 - 0.6 62.40 62.90 1593.89 13 10 7 g1310 7.93E-03 9270 1.56E-12 3.11E-12 1.00 1.00 2.00 3.46E-12 3.22E-04 109103 132420 -23317 -21.37 
12b 62.40 62.90 1593.31 13 10 7 5.95E-03 5705 1.92E-12 3.85E-12 105538 125220 -19682 -18.65 
13a 0.4 - 0.6 62.44 65.02 1593.06 13 13 7 g1313 3.37E-03 320900 6.82E-15 1.36E-14 0.75 1.00 1.75 2.66E-14 6.40E-05 420733 269310 151423 35.99 
13b 62.59 65.24 1593.51 13 13 7 7.93E-03 159800 4.88E-14 9.77E-14 259633 385320 -125687 -48.41 
13c 62.59 65.24 1593.51 13 13 7 4.16E-03 360400 7.05E-15 1.41E-14 460233 293090 167143 36.32 
14a 0.4 - 0.6 64.73 68.90 1593.59 15 16 7 g1516 7.93E-03 86400 1.17E-13 2.34E-13 0.75 1.00 1.75 2.69E-13 1.38E-04 4.04E-13 1.57E-04 186233 185340 893 0.48 
14b 64.73 68.90 1593.59 15 16 7 7.93E-03 81300 1.27E-13 2.53E-13 181133 185340 -4207 -2.32 
14c 64.66 68.78 1593.35 15 16 7 3.57E-03 34400 1.65E-13 3.30E-13 134233 146200 -11967 -8.92 
15a 0.6 - 0.8 62.40 62.90 1592.97 13 10 8 h1310 8.92E-03 10470 1.50E-12 3.01E-12 0.75 1.00 1.75 6.45E-12 3.99E-04 110314 133120 -22806 -20.67 
15b 62.40 62.90 1592.06 13 10 8 8.92E-03 2140 7.14E-12 1.43E-11 101984 133120 -31136 -30.53 
15c 62.40 62.90 1592.06 13 10 8 6.94E-03 1466 8.14E-12 1.63E-11 101310 126650 -25340 -25.01 
15d 62.40 62.90 1592.39 13 10 8 5.95E-03 8220 1.24E-12 2.47E-12 108064 123260 -15196 -14.06 
16a 0.6 - 0.8 64.28 68.14 1592.07 15 16 8 h1516 5.95E-03 210000 2.19E-14 4.38E-14 0.75 1.00 1.75 9.45E-14 9.76E-05 309844 227740 82104 26.50 
16b 64.42 68.39 1592.56 15 16 8 3.96E-03 53750 1.02E-13 2.04E-13 153594 196310 -42716 -27.81 
17 0.6 - 0.8 62.40 62.90 1591.78 13 10 9 i1310 5.95E-03 960 1.04E-11 2.08E-11 0.75 1.00 1.75 2.08E-11 5.90E-04 100816 116430 -15614 -15.49 
18a 0.6 - 0.8 61.88 64.23 1591.38 12 12 9 i1212 7.93E-03 164690 3.95E-14 7.90E-14 4.00 4.00 8.00 3.86E-14 6.14E-05 264546 307180 -42634 -16.12 
18b 61.78 64.08 1591.06 12 12 9 5.15E-03 306000 9.43E-15 1.89E-14 405856 257760 148096 36.49 
19a 0.6 - 0.8 62.00 64.41 1591.75 13 12 9 i1312 3.57E-03 79600 5.13E-14 1.03E-13 2.00 0.25 2.25 1.00E-13 9.84E-05 179456 186030 -6574 -3.66 
19b 62.08 64.52 1591.99 13 12 9 6.94E-03 135200 4.90E-14 9.80E-14 235056 236290 -1234 -0.52 
20 0.6 - 0.8 64.00 67.69 1591.14 14 15 9 i1415 3.96E-03 193600 1.51E-14 3.03E-14 0.75 0.75 1.50 3.03E-14 6.74E-05 293456 287860 5596 1.91 
21 0.6 - 0.8 64.09 67.84 1591.46 15 15 9 i1515 5.95E-03 240000 1.67E-14 3.34E-14 0.75 1.00 1.75 3.34E-14 6.91E-05 339856 334740 5116 1.51 
22 0.6 - 0.8 64.19 68.00 1591.78 15 16 9 i1516 3.96E-03 190700 1.65E-14 3.29E-14 0.75 1.00 1.75 3.29E-14 6.87E-05 1.89E-13 1.22E-04 290556 278340 12216 4.20 
23 0.8 - 1.0 61.48 63.66 1590.16 12 11 10 j1211 3.96E-03 343350 5.71E-15 1.14E-14 0.50 1.00 1.50 1.14E-14 4.64E-05 443217 388130 55087 12.43 
24a 0.8 - 1.0 63.73 67.24 1590.24 14 15 10 j1415 7.93E-03 37 3.24E-10 6.47E-10 1.00 1.00 2.00 5.02E-11 7.38E-04 99904 113430 -13526 -13.54 
24b 63.95 67.61 1590.99 14 15 10 3.96E-03 218700 1.24E-14 2.48E-14 318567 106950 211617 66.43 
24c 63.71 67.22 1590.19 14 15 10 6.94E-03 33 3.17E-10 6.34E-10 99900 111860 -11960 -11.97 
24d 63.71 67.22 1590.19 14 15 10 9.31E-03 45 3.12E-10 6.25E-10 99912 115560 -15648 -15.66 
25 0.8 - 1.0 61.34 63.46 1589.73 12 11 11 k1211 1.98E-03 449000 1.81E-15 3.61E-15 0.50 1.00 1.50 3.61E-15 3.16E-05 548879 463060 85819 15.64 
26a 0.8 - 1.0 63.45 66.79 1589.33 14 14 11 k1414 7.93E-03 31 3.89E-10 7.77E-10 1.00 1.00 2.00 8.12E-10 1.87E-03 1.14E-12 2.09E-04 99910 100180 -270 -0.27 
26b 63.48 66.83 1589.40 14 14 11 9.31E-03 41 3.44E-10 6.89E-10 99920 100230 -310 -0.31 
26c 63.48 66.83 1589.40 14 14 11 6.94E-03 21 5.01E-10 1.00E-09 99900 100140 -240 -0.24 
27 rubble zone 62.40 62.90 1588.43 13 10 12 l1310 7.93E-03 48 2.64E-10 1.06E-09 1.00 1.00 2.00 1.06E-09 8.59E-04 1.06E-09 8.59E-04 99938 99952 -14 -0.01 
28a lower basalt 62.96 65.98 1587.68 13 13 13 m1313 3.96E-03 16 4.20E-10 1.68E-09 1.00 1.00 2.00 1.19E-09 1.92E-03 99918 99941 -23 -0.02 
28b 62.96 65.98 1587.68 13 13 13 6.94E-03 56 2.10E-10 8.39E-10 99958 99970 -12 -0.01 
29a lower basalt 62.72 65.59 1586.89 13 13 14 n1313 7.33E-03 78 1.67E-10 6.69E-10 1.00 1.00 2.00 1.29E-11 4.26E-04 99991 102130 -2139 -2.14 
29b 62.48 65.20 1586.09 13 13 14 7.33E-03 124000 6.21E-14 2.48E-13 223913 102130 121783 54.39 
30 lower basalt 62.33 64.94 1585.58 13 12 15 o1312 7.33E-03 50 2.68E-10 1.07E-09 1.00 1.00 2.00 1.07E-09 1.86E-03 99975 99945 30 0.03 
31 lower basalt 61.93 64.28 1584.24 12 12 16 p1212 7.93E-03 3 4.31E-09 1.72E-08 1.00 1.00 2.00 1.72E-08 4.69E-03 99939 99981 -42 -0.04 
32 lower basalt 61.36 63.36 1582.36 12 11 18 r1211 7.33E-03 2595 4.48E-12 1.79E-11 1.00 1.00 2.00 1.79E-11 4.76E-04 3.48E-10 1.28E-03 102555 101570 985 0.96 
8647 Pa 
15962 Pa 
RMS error = 
residual bias = 
Calibration Centroid of Injection Interval Field Data Background Param. Node Nodal Parameters

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 48 March 2000 
INTENTIONALLY LEFT BLANK

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 49 March 2000 
To calibrate the permeability of the fracture continuum nodes, we removed the matrix continuum 
nodes to facilitate decreased simulation times. This procedure is consistent with the calibration 
methodology employed at Yucca Mountain (Huang et al. 1999) where the injected air is assumed 
to flow entirely through the fractures. Calibration of the model involved initially setting the 
gas-phase pressure equal to 100 kPa along the bottom boundary and decreasing it statically 
upwards to the top boundary. Constant pressure gas-phase boundary conditions were fixed at all 
sides of the model. Calibration then proceeded by adjusting the permeability of each fracture 
continuum node within which the centroid of an injection interval was located, until the model 
closely matched the observed field pressure response at steady state for the applied injection rate. 
The background permeability of each zone within the upper basalt flow (in addition to the rubble 
zone and lower basalt) was calculated by taking the geometric mean permeability of all nodes (see 
kmean of Nodal Parameters section on Table 6-5) within which air injection took place for each 
specific zone. This calibration methodology is only meant to estimate the mean permeability of 
each of the various zones and does little to determine the spatial continuity in the permeability 
field around boreholes S-3, S-4 and II-5. This objective was considered sufficient for the purpose 
of this calibration, given that an estimate for the site-wide permeability was needed in order to 
simulate the infiltration tests. 
The steady-state water saturation profile was established by applying an infiltration rate of 
0.01 m/yr to the fracture continuum nodes along the surface of the model. This resulted in a 
maximum water saturation of 0.23 along the top of the model that decreased to 0.05 at the bottom. 
Permeability calibration by air injection was found to be insensitive to these low water saturations 
because the injected air always reduced the water saturation at the injection node and immediately 
surrounding nodes to a residual value of 0.01 at steady state. 
The permeability values used to calibrate the model for each injection node are given in column 
kmodel of Table 6-5. These values are all two or four times larger than those estimated by Baehr 
and Hult (1991). This difference is considered satisfactory given that the analytical model does 
not take into account the 3-dimensional structure of air flow in the fracture network. Multiple tests 
often had the centroids of their packer intervals within the same node. A single permeability value 
was then estimated for each node by taking the geometric mean value of all the individual tests 
within the particular node. The fracture aperture, b, of the node was then estimated by assuming 
the permeability tensor was isotropic, kx = ky = kz = mean of kmodel, so that b was the arithmetic 
mean value calculated from Equations 1 through 3. The background fracture aperture was 
calculated in an identical manner. The background permeability and porosity values for the 
various zones of the upper basalt, rubble zone and lower basalt are provided under section 
Background Param. of Table 6-5. 
The results of the model calibration are described on Table 6-5 under the calibration subsection. 
The residual, .Presidual, is calculated as the change in pressure observed in the field minus the 
change in pressure simulated in the model at the node in which injection took place. The values of 
Pfield and Pmodel include the static gas phase pressure at the injection node. The percent error, % 
error is the residual, .Presidual, divided by Pfield. The RMS error, which is the square-root of the 
mean of the sum of the squares of the residuals, is 8647 Pa, which is larger than 22 of the 51 
pneumatic pressure responses. This is caused by the difficulty in matching the large pressure

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 50 March 2000 
increase in the low permeability injection nodes by adjusting only the permeability of the 
injection node along with the mean background value. Injection node permeability values that 
were similar to or higher than the mean background value were more accurately simulated by the 
model. The residual bias, calculated as the arithmetic mean of .Presidual, is 15962 Pa, also 
indicating that the fit was poorest for injection nodes within the lowest permeabilities that 
subsequently induced the largest pressure response. The RMS and residual bias errors indicate 
that the calibration methodology used is only suitable for estimating the average background 
permeability and should not be interpreted as a precise fit to the data from each test. Using an 
inverse model capable of estimating spatial continuity of the permeability field could significantly 
reduce the RMS and residual bias calibration errors. At the same time, these data show the 
validity of the volume-averaged approach of estimating the air permeability of rocks as performed 
at Yucca Mountain. 
The permeability of the rubble zone is at least three orders of magnitude higher than that of the 
upper basalt. Although the permeability was estimated using only one measurement, it is 
consistent with field observations indicating that it is a highly permeable layer that provides a 
distinct hydrogeological separation between the upper and lower basalt flows. The bottom of the 
rubble zone is difficult to delineate from core data and may extend further into the lower basalt 
than shown on Figure 6-4. This would explain the higher permeabilities measured in the lower 
basalt relative to the upper basalt flow. 
6.5.1.1.5 Infiltration Test Analysis 
Two sequential sets of infiltration experiments were conducted at Box Canyon. The first is labeled 
96-1 (two-week ponded infiltration test) while the second consists of four separate infiltration 
events called 97-1, 97-2, 97-3 and 97-4 (2-to-4 day infiltration tests). All tests were conducted 
within the infiltration pond shown on Figure 6-2b. Details concerning the infiltration experiments 
can be found in Faybishenko et al. (1998a, 1999). The starting time and duration of all ponding 
events is provided in Table 6-6, while the infiltration rates measured during the ponding events 
are provided in Table 6-7. 
Table 6-6 . Ponding Test Initiation and Duration Times 
DTN: LB990930123122.001 
Test Start of Ponding End of Ponding Test Time Since 
Duration Datum 
(days) (days) 
96-1 8/27/96 12:27 9/9/96 11:00 12.94 0.00 
97-1 9/11/97 12:15 9/13/97 12:45 2.02 379.99 
97-2 9/18/97 14:56 9/20/97 16:46 2.08 387.10 
97-3 10/2/97 15:40 10/4/97 16:00 2.01 401.13 
97-4 10/31/97 13:51 11/3/97 15:00 3.05 430.06

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 51 March 2000 
Table 6-7. Ponding Test Infiltration Rates 
DTN: LB990930123122.001 
Analysis of the infiltration experiments involved calibrating hydrogeological parameters in the 
dual-permeability model of the Box Canyon site to match the arrival times of the infiltration front 
at various monitoring points. Simulations were also performed to determine whether the fracture 
pattern inferred from active water flow features in the subsurface acts to preferentially redistribute 
the infiltrating water within the computational domain. Furthermore, the model was used to 
examine the influence of the zonation pattern in fracture densities within the basalt flow and 
rubble zone on flow patterns of the infiltrating water. The permeability of the fracture continuum 
Infiltration Time since Infiltration 
Test 96-1 Rate 
(days) (m/day) 
96-1 0.00 0.110 
0.50 0.100 
1.00 0.095 
1.50 0.085 
2.00 0.080 
2.50 0.075 
3.00 0.065 
3.50 0.060 
4.00 0.054 
4.50 0.050 
12.94 0.030 
97-1 379.99 0.100 
380.24 0.075 
380.49 0.060 
380.99 0.040 
381.49 0.030 
382.01 0.025 
97-2 387.10 0.175 
387.23 0.120 
387.35 0.800 
387.48 0.060 
387.60 0.045 
387.85 0.035 
388.10 0.030 
389.18 0.025 
97-3 401.13 0.065 
401.63 0.045 
402.13 0.030 
403.15 0.025 
97-4 430.06 0.040 
432.06 0.030 
433.11 0.025

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 RE V00 52March 2000 
nodes for the dual-permeability model was taken directly from the pneumatic test calibration. 
Other relevant parameters are provided in Table 6-2; their source is discussed below. 
Boundary conditions applied to the numerical model for simulating the infiltration experiments 
consisted of a constant gas phase pressure of 100 kPa along the bottom of the model which then 
decreased statically upwards. All sides of the model were constrained as constant gas-phase 
pressure boundary conditions. An infiltration rate of 0.1 m/yr resulting from recharge was used to 
establish the steady-state water saturation profile. The gas-phase pressure distribution and 
steady-state water saturation profiles were used as initial conditions for all subsequent transient 
simulations. For the infiltration test simulations, the slightly irregular nature of the infiltration 
pond was approximated to fit within coordinates (58 m E, 60 m N) to (67 m E, 69 m N) in order to 
conform to the regular nature of the grid. Infiltration of the ponded water was simulated by 
injecting water at the rate observed during each event (Faybishenko et al. 1999) as specified on 
Table 6-7 to every fracture continuum node at the top of the model within the perimeter of the 
infiltration pond. No attempt was made to redistribute the infiltrating water with respect to the 
inferred fracture network shown on Figure 6-5 or based on variations in ground surface elevation 
within the pond. The constant pressure gas-phase boundary condition was removed from the 
surface nodes within the perimeter of the pond. 
6.5.1.1.5.1 Calibration Using Infiltration Front Arrival Times 
Calibration of hydrogeological parameters controlling the infiltration rate of water in the 
fracture-matrix basalt system involved adjusting the porosity of the fracture continuum, the 
permeability of the matrix continuum, and the interfacial area between the fracture and matrix 
continua. These parameters were modified until the infiltration front arrival times simulated by 
the numerical model matched field data obtained at sampling intervals during the infiltration 
events. The arrival times of the infiltration front were inferred from the first significant increase in 
bromide concentration in water samples taken as part of the tracer tests conducted during each 
infiltration test. Therefore, it was assumed, as stated in Section 5, Assumption #10, that the 
bromide tracer was conservative and advected at the same velocity as the infiltration front in the 
fracture continuum. It is important to note that the bromide data were used to constrain parameters 
controlling variably saturated groundwater flow. Transport of bromide was not simulated within 
the variably saturated flow field. 
Tsang (1992) provided a literature review to sort out the different definitions and denotations of 
the various equivalent apertures that arose due to field measurements regarding the relative 
magnitudes of hydraulic aperture and tracer aperture. These definitions pertained to 
representing a rough-walled fracture by a pair of parallel plates separated by a constant aperture b. 
Under fully saturated conditions, hydraulic tests provided an equivalent parallel plate aperture 
given by the geometric mean of the aperture distribution between the rough-walled fracture 
surfaces, while tracer tests indicated an arithmetic mean aperture. Therefore, advection of a tracer 
in rough-walled fractures should occur more rapidly than hydraulic testing would indicate. 
Extension of this rule-of-thumb to the Box Canyon site is made difficult by the variably 
saturated nature of the fractures. In this case, the infiltration front is channeled by the largest 
apertures while some water is drawn into the smaller apertures by capillary forces due to the 
wetting nature of the water phase on the fracture surfaces (Pruess, 1998). The equivalent fracture 
required by the fracture continuum nodes to conduct the infiltrating water may then be closer to

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 53 March 2000 
the arithmetic mean of the aperture distribution. In this work, we assume, as stated in Section 5, 
Assumption #6, that the equivalent aperture obtained from the pneumatic, infiltration, and tracer 
tests are identical by using the bromide data to infer the arrival time of the infiltration front. 
Tracer tests conducted during the 97-1 to 97-4 series of infiltration tests provided the most 
comprehensive set of bromide measurements and consequently were used during the calibration. 
Given that the 96-1 bromide tracer test had been conducted previously, there was a preexisting 
background concentration of bromide prior to the start of the 97-1 test. Table 6-8 provides the 
background bromide concentrations measured prior to the 97 series of infiltration tests. Statistical 
analysis of the data indicated that they were log-normally distributed with a mean of 4.35 ln(mg/l) 
(or 77.48 mg/l) and a standard deviation of 0.94 ln(mg/l). Given these statistics, a bromide 
concentration of 240 mg/l provided a 88.5% confidence interval for the bromide concentration 
being significantly greater than the mean background concentration. This concentration was 
approximatgely 0.08 of the source pond bromide concentration used in 96-1 and 0.1 of the source 
pond bromide concentration used in 97-1 to 97-4 which is demonstrated by the maximum 
bromide concentration shown on Table 6-8. The maximum bromide concentration is reached at 
late time and is quite variable in magnitude due to variability within the pond itself. Therefore, the 
first sampling event when the bromide concentration exceeded 240 mg/l was used to infer the 
infiltration front arrival at that sampling point. This inference assumes, as stated in Section 5, 
Assumption #10, that dilution of the bromide tracer in the fracture continuum at the infiltration 
front, because of dispersion and losses into the matrix continuum, did not attenuate a bromide 
concentration of 0.1 of the source value. These times are listed as the maximum bromide arrival 
times on Table 6-9. The sampling time immediately prior to when bromide exceeded 240 mg/l is 
listed as the minimum bromide arrival time on Table 6-9. Together, the maximum and minimum 
provide a window on the expected arrival time of the infiltration front at the sampling point. In 
some cases, the first bromide sample exceeded a concentration of 240 mg/l, setting the maximum 
value on the time window, but no prior sample was taken to set the minimum value on the 
window. In this case, the minimum arrival time of the infiltration front was set as the start of the 
97-1 infiltration test by default.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 54 March 2000 
Table 6-8. Background Bromide Concentrations Prior to the 97-1 to 97-4 Infiltration Tests. 
DTN: LB9909301123122.001 
Well ID Vertical Max. Br- 
Depth Conc. mean # samples sample 1 sample 2 
(m) (mg/l) (mg/l) (mg/l) (mg/l) 
E1 1.50 2256.76 - 0 
E2 7.20 55.98 - 0 
11.70 231.78 63.38 1 63.38 
E3 5.50 143.55 34.96 2 34.96 34.96 
7.30 103.99 68.80 1 68.80 
E4 3.50 308.50 - 0 
7.50 81.67 56.90 1 56.90 
13.40 56.62 - 0 
I1 0.30 106.69 45.39 2 43.70 47.07 
1.50 2048.92 - 0 
3.00 353.15 - 0 
6.10 41.91 46.56 2 38.05 55.07 
8.50 378.41 124.46 1 124.46 
10.10 429.72 43.66 2 44.24 43.08 
I2 0.30 2736.95 53.96 2 56.60 51.32 
1.50 1438.37 - 0 
3.00 1703.16 - 0 
6.10 2661.59 - 0 
I3 0.30 3460.86 42.09 2 41.32 42.86 
1.50 926.81 53.35 1 53.35 
T2 1.80 1490.44 845.23 1 845.23 
4.40 213.56 117.57 1 117.57 
T3 4.60 2110.00 - 0 
T4 0.60 2060.86 54.01 1 54.01 
2.70 1024.37 - 0 
4.30 1046.65 204.00 1 204.00 
5.80 1068.52 - 0 
T5 1.50 - 47.98 1 47.98 
3.00 507.62 - 0 
T6 0.60 2909.92 - 0 
4.60 1809.34 - 0 
T7 0.60 4040.73 66.39 1 66.39 
1.80 1042.95 829.34 2 778.14 880.53 
3.00 964.10 - 
5.80 - 89.73 1 89.73 
T8 0.30 2268.61 - 
T9 0.30 2609.84 54.55 1 54.55 
1.50 2648.43 - 
Background Br- Conc.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 55 March 2000 
Table 6-9. Bromide Arrival Times During the 97-1 to 97-4 Infiltration Test. 
DTN: LB990930123122.001 
Calibration of the model was performed by extracting one-dimensional vertical columns from 
beneath the infiltration pond where the 97-1 bromide data indicated borehole intersections with 
fractures that actively conducted water. Therefore, it was assumed that the infiltration front in the 
full three-dimensional model progressed downwards in a one-dimensional manner along vertical 
columnar fractures to each sampling point. Calibration involved the use of the one-dimensional 
columns rather than the full three-dimensional model to significantly reduce simulation times. 
Discretization of the one-dimensional columns consisted of the same 1.0 m3 blocks used to 
discretize the site model. Although numerical accuracy in terms of resolving the water saturation 
at the infiltration front could be significantly improved with a finer discretization, discretization 
of the columns was identical to the site model. This allowed calibration parameters to be 
transferred directly to the site model and avoided concerns regarding scaling issues. 
Parameter estimation was performed manually. Consequently, only a qualitative analysis of a 
given parameters sensitivity to the overall calibration process is provided. A systematic 
calibration methodology using an inverse model such as ITOUGH2 (Finsterle 1999) would 
9/11/97 12:15 PM 
Well ID Vertical 
Depth 
(m) (date) (days) (date) (days) 
E1 1.50 9/12/97 10:29 AM 0.93 - - 
E4 3.50 9/25/97 5:32 PM 14.22 9/20/97 1:10 PM 9.04 
I1 1.50 9/12/97 9:04 AM 0.87 9/11/97 7:21 PM 0.30 
3.00 10/16/97 12:28 PM 35.01 - - 
8.50 10/31/97 12:12 PM 50.00 9/8/97 10:20 AM -3.08 
10.10 9/25/97 6:12 PM 14.25 9/19/97 5:31 PM 8.22 
I2 0.30 9/11/97 7:37 PM 0.31 9/10/97 3:13 PM -0.88 
1.50 9/12/97 3:17 PM 1.13 - - 
3.00 9/20/97 12:22 PM 9.00 - - 
6.10 9/18/97 7:29 PM 7.30 9/11/97 7:20 PM 0.30 
I3 0.30 9/11/97 6:59 PM 0.28 9/10/97 3:49 PM -0.85 
1.50 10/4/97 12:48 PM 23.02 9/8/97 10:40 AM -3.07 
T3 4.60 9/26/97 2:34 PM 15.10 - - 
T4 0.60 9/21/97 10:00 AM 9.91 9/19/97 4:35 PM 8.18 
2.70 9/20/97 1:26 PM 9.05 - - 
4.30 9/17/97 6:50 PM 6.27 - - 
5.80 9/21/97 10:00 AM 9.91 9/20/97 1:23 PM 9.05 
T5 3.00 10/16/97 1:41 PM 35.06 10/4/97 12:58 PM 23.03 
T6 0.60 9/11/97 7:10 PM 0.29 - - 
4.60 11/3/97 3:30 PM 53.14 - - 
T7 0.60 9/11/97 7:04 PM 0.28 9/10/97 3:42 PM -0.86 
3.00 9/20/97 12:45 PM 9.02 - - 
T8 0.30 9/12/97 8:55 AM 0.86 - - 
T9 0.30 9/11/97 7:34 PM 0.30 9/10/97 3:27 PM -0.87 
1.50 9/11/97 7:32 PM 0.30 - - 
Br- > 240 mg/l Br- < 240 mg/l 
Max. Br- Arrival Time Min. Br- Arrival Time 
Time datum for Br- arrival times (start of 97-1):

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 56 March 2000 
provide a better understanding of the interrelationship of parameters assumed to control 
preferential flow paths of infiltrating water in the fractured basalt at Box Canyon. This approach 
would require detailed coordination between the field and modeling efforts to obtain data sets of 
sufficient quality to withstand the rigorous statistical analysis performed during inverse modeling. 
Calibration was initially performed by matching infiltration front arrival times at borehole I-1 at 
vertical depths of 1.5 m and 10.1 m below the ground surface. Calibration proceeded by manually 
adjusting the fracture continuum porosity as calculated from the fracture aperture given by 
Equation 4, the matrix continuum permeability, and fracture-matrix interfacial area given by 
Equation 5. Justification for scaling the fracture continuum porosity is based on fractures having 
rough walls that create an irregular aperture distribution. Fractures may have many dead-end 
channels that contribute to tortuous flow of water through the fracture plane. Increasing the 
fracture porosity acts to slow down the rate at which the infiltration front advects through the 
fracture continuum. Matrix permeability was adjusted using the core sample values provided on 
Table 6-4 because large-scale vesicular zones are distributed throughout the basalt matrix. These 
act to increase permeability of the matrix continuum at the 1 m3 scale of the nodes relative to the 
core scale. Increasing matrix permeability acts to slow down the rate at which the infiltration front 
advects through the fracture continuum because the matrix continuum is also able to conduct a 
portion of the infiltrating water. Increasing matrix permeability also acts to dampen the increase in 
water saturation at the infiltration front, attenuating its migration rate, because the matrix then 
responds more rapidly to the flow of water from the fracture continuum. This flow of water occurs 
because the capillary pressure within the fracture continuum decreases substantially at the 
infiltration front where the water saturation approaches unity. The capillary pressure, along with 
the water saturation, changes much more slowly in the matrix continuum than in the fracture 
continuum because of the large matrix storage capacity. The difference in water potentials caused 
by the disequilibrium in the fracture and matrix continua then causes the flow of water from the 
fracture into the matrix continuum. 
The fracture-matrix interfacial area given by Equation 5 was scaled downward to decrease the 
exchange of water between the fracture and matrix continua nodes at the infiltration front 
resulting from the influence of the capillary forces. This parameter is expected to be small given 
that channelized flow of water is observed to occur in fractures (Pruess 1998; Su et al. 1999). This 
implies significantly less contact area for water between the fracture and matrix continua than if 
sheet flow were to occur in the fracture plane. Reduction in interfacial area acts to decrease the 
influence of the matrix continuum on the fracture continuum, thereby increasing the rate at which 
the infiltration front advects in the fracture continuum. 
Calibration results for borehole I-1 are shown in Figure 6-10, which shows the change in water 
saturation in the fracture and matrix continuum nodes as a function of time where the time datum 
is the start of the 96-1 infiltration test. Sampling point I-1 at a depth of 1.5 m shows a rapid water 
saturation change within the time window specified by the bromide data. This response occurred 
immediately after the 97-1 test, indicating that the infiltration front advected rapidly through the 
fracture continuum near the ground surface. Sampling point I-1 at a depth of 10.1 m also responds 
within the time window specified by the bromide data, although the response does not occur until 
during the 97-2 infiltration test. All of the water that had infiltrated from the 97-1 test was 
completely absorbed from the fracture into the matrix continuum nodes before the infiltration

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 57 March 2000 
front could reach a depth of 10.1 m. It was not until the 97-2 test that a sufficient increase in water 
saturation relative to steady-state conditions existed in the matrix to allow the infiltration front to 
propagate to a greater depth. 
DTN: LB990930123122.002 
Figure 6-10. Simulated Infiltration Front Arrival Times at Sampling Points in Borehole I-1 Given by 
Water Saturation in the Fracture (Swf ) and Matrix (Swm) Continua 
Fracture and matrix continuum properties obtained during the calibration for borehole I-1 are 
given in Table 6-2. Of particular note is that the fracture porosity was scaled upward by a factor of 
50 relative to the fracture porosity from the permeability calibration exercise. Porosity was an 
extremely sensitive parameter controlling the infiltration rate of water in the fracture continuum. 
The resulting fracture continuum porosity for the upper basalt ranged from 0.01 to 0.02. The 
matrix permeability was increased by a factor of 4.5 to reflect the presence of vesicular zones 
distributed throughout the upper basalt. The fracture-matrix interfacial area was scaled by a factor 
of 0.01 to allow the matrix to completely absorb the 97-1 infiltration front between a depth of 
1.5 m and 10.1 m while allowing the 97-2 infiltration front to propagate to a depth of 10.1 m. 
Capillary pressure in both the variably saturated matrix and fracture continua nodes was 
represented using van Genuchten functions as implemented in TOUGH2 codes (Pruess 1991) 
with a and m parameters provided in Table 6-2. Although no formal capillary pressure-water 
saturation data have been obtained to characterize either the fractures or basalt matrix at Box 
Canyon, this choice of parameters yielded capillary pressures in the range of 10 kPa to 50 kPa, 
which was consistent with tensiometer measurements from the site (Faybishenko et al. 1998a, 
1999). Residual water saturations of 0.01 and 0.1 were used in the fracture and matrix continua, 
respectively. 
380 385 390 395 400 
0 
0.1 
0.2 
0.3 
0.4 
0.5 
0.6 
0.7 
0.8 
0.9
1 
Time (days) 
Water Saturation; Swf, Swm 
97-1 
97-2 
97-3 
I-1: 1.5m - Swf 
I-1: 10.1m - Swf 
I-1: 1.5m - Swm 
I-1: 10.1m - Swm 
min 
max 
min 
max 
380 385 390 395 400 
0 
0.1 
0.2 
0.3 
0.4 
0.5 
0.6 
0.7 
0.8 
0.9
1 
Time (days) 
Water Saturation; Swf, Swm 
97-1 
97-2 
97-3 
I-1: 1.5m - Swf 
I-1: 10.1m - Swf 
I-1: 1.5m - Swm 
I-1: 10.1m - Swm 
min 
max 
min 
max

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 58 March 2000 
The relative permeability of the water and gas phases in both the matrix and fracture continuum 
nodes were represented using the Corey function, as implemented in TOUGH2, rather than the 
van Genuchten function as conventionally used for the Yucca Mountain simulations. Figure 6-11 
shows the relative permeability of the infiltrating water phase using both van Genuchten and 
Corey functions in the fracture and matrix continua. The van Genuchten curves exhibit a very 
steep slope as the water saturation approaches unity, whereas the slope of the Corey curves when 
the water saturation is unity equals three. The steep slope of the van Genuchten curve 
substantially increased the numerical difficulty for the Newton iteration relative to the Corey 
curve. Use of the van Genuchten function increases the water saturation in the fracture and matrix 
continua relative to that simulated using the Corey curve. This requires a corresponding increase 
in the fracture-matrix interfacial area scaling factor to imbibe the water from the 97-1 infiltration 
test. The sensitivity of the calibration results to uncertainty in the form of the relative permeability 
curve implies that water saturation as well as relative permeability data are necessary in order to 
constrain the uniqueness of the calibration results. Given that these data do not exist for the Box 
Canyon site, the Corey relative permeability curve was used due to numerical efficiency 
DTN: LB990930123122.002 
Figure 6-11. Van Genuchten and Corey Relative Permeability Curves for the Fracture and Matrix 
Continua 
The possibility of non-uniqueness existed during the calibration of the I-1 column because three 
parameters were adjusted to calibrate the model to the arrival time of an infiltration front at two 
different depths. The possibility of non-uniqueness is addressed by determining whether 
parameters used to calibrate I-1 are capable of predicting infiltration front arrival times at other 
sampling locations where bromide data are available. 
Figure 6-12 shows calibration results for sampling intervals within borehole I-2 using 
hydrogeological parameters estimated from the I-1 calibration. The only sampling point in 
0 0.2 0.4 0.6 0.8 1 
10-5 
10-4 
10-3 
10-2 
10-1 
100 
fracture, van Genuchten 
fracture, Corey 
matrix, van Genuchten 
matrix, Corey 
Water Saturation Sw 
Relative Permeability krw

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 59 March 2000 
borehole I-2 that has both a minimum and maximum expected arrival time occurs at a depth of 
6.1 m. The minimum arrival time occurs 0.3 days after the start of the 97-1 test and the maximum 
occurs only 0.2 days after the start of the 97-2 test. Examination of Figure 6-12 shows that the 
majority of the simulated infiltration water from the 97-1 test is absorbed into the matrix before 
the start of the 97-2 test, although a small 0.08 increase in water saturation does reach a depth of 
6.1 m. This is the remnant of a severely attenuated infiltration front from the 97-1 test. At the start 
of the 97-2 test, the water saturation rapidly increases after 0.2 days, although the peak saturation 
of the infiltration front arrives 0.5 days after the maximum expected arrival time. In general, these 
parameters do capture the rapid arrival of water after the start of the 97-2 test, although the arrival 
time could be increased by decreasing the porosity multiplier given in Table 6-2. As the sampling 
depth decreases from 6.1 m to 3.0 m, 1.5 m and finally 0.3 m, the arrival time of the infiltration 
front increases dramatically. Both sampling depths of 0.3 m and 1.5 m show peak water 
saturations before the maximum expected arrival time of the infiltration front. Simulation of the 
infiltration front at a depth of 3.0 m yielded an arrival time shortly after the 97-1 test, although the 
maximum expected time as inferred from the bromide data did not occur until after the start of the 
97-2 test. The significance of this is impossible to infer given that no minimum expected arrival 
time could be obtained from the bromide data. 
Given the relatively coarse discretization, permeability differences within the upper basalt flow 
that were within an order-of-magnitude of one another, and the fact that the infiltration rate from 
the pond was applied uniformly to all nodes within the perimeter of the infiltration pond, the 
arrival time of the infiltration front at shallow depths such as 1.5 m at I-2 is expected to be similar 
to that for I-1 at the same depth. Confirmation of the non-uniqueness of the parameters chosen to 
simulate I-1 is given by the simulated behavior of the infiltration front at a depth of 6.1 m in I-2. 
DTN: LB990930123122.002 
Figure 6-12. Simulated Infiltration Front Arrival Times at Sampling Points in Borehole I-2 Given by 
Water Saturation in the Fracture (Swf ) and Matrix (Swm) Continua 
380 385 390 395 400 
0 
0.1 
0.2 
0.3 
0.4 
0.5 
0.6 
0.7 
0.8 
0.9
1 
Time (days) 
Water Saturation; Swf, Swm 
97-1 
97-2 
97-3 
I-2: 0.3m - Swf 
I-2: 1.5m - Swf 
I-2: 0.3m - Swm 
I-2: 1.5m - Swm 
max max 
min 
max 
max 
I-2: 6.1m - Swf 
I-2: 3.0m - Swf 
I-2: 3.0m - Swm 
I-2: 6.1m - Swm

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ANL-NBS-HS-000007 REV00 60 March 2000 
Figure 6-13 shows the arrival time of the infiltration front for borehole T-5 at a depth of 3.0 m. 
Bromide data indicated that the maximum and minimum expected arrival times of the infiltration 
front did not occur until after the start of the 97-3 test. Examination of the simulated arrival times 
indicates that the model predicts that the infiltration front should arrive after the 97-2 test. This 
implies that the fracture-matrix interfacial area may have been significantly higher for the 
columnar fracture extending downward to borehole T-5 at a sampling depth of 3.0 m, causing 
both the 97-1 and 97-2 test infiltration fronts to be absorbed into the matrix. Alternatively, the 
fracture pathway may not have been an active conduit for water during one or both of the 97-1 
and 97-2 tests. These results indicate that the ability to simulate preferential flow of infiltrating 
water in a specific columnar fracture relative to another can only be performed using the full 
three-dimensional site model. 
DTN: LB990930123122.002 
Figure 6-13. Simulated Infiltration Front Arrival Times at Sampling Points in Boreholes T-5 and T-6 
Given by Water Saturation in the Fracture (Swf ) and Matrix (Swm) Continua 
Figures 6-13 to 6-15 show simulated infiltration front arrival times for boreholes T-6, T-7, T-8, 
T-9, E-1 and I-3. All of these sampling points are relatively shallow and do not include a 
minimum expected infiltration front arrival time from the bromide data. Therefore, no 
interpretation is provided for these sampling intervals. 
380 390 400 410 420 430 
0 
0.1 
0.2 
0.3 
0.4 
0.5 
0.6 
0.7 
0.8 
0.9
1 
Time (days) 
Water Saturation; Swf, Swm 
97-1 
97-2 
97-3 
T-6: 4.6m - Swf 
T-6: 0.6m - Swm 
max 
97-4 
min 
max 
max 
T-6: 0.6m - Swf 
T-6: 4.6m - Swm 
T-5: 3.0m - Swf 
T-5: 3.0m - Swm

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 61 March 2000 
DTN: LB990930123122.002 
Figure 6-14. Simulated Infiltration Front Arrival Times at Sampling Points in Boreholes T-9 and E-1 
Given by Water Saturation in the Fracture (Swf ) and Matrix (Swm) Continua 
DTN: LB990930123122.002 
Figure 6-15. Simulated Infiltration Front Arrival Times at Sampling Points in Borehole I-3, T-7 and T-8 
Given by Water Saturation in the Fracture (Swf ) and Matrix (Swm) Continua 
380 385 390 395 400 
0 
0.1 
0.2 
0.3 
0.4 
0.5 
0.6 
0.7 
0.8 
0.9
1 
Time (days) 
Water Saturation; Swf, Swm 
97-1 
97-2 
97-3 
T-9: 0.3m - Swf
T-9: 1.5m - Swf 
T-9: 0.3m - Swm 
T-9: 1.5m - Swm 
max 
max 
max 
E-1: 1.5m - Swf 
E-1: 1.5m - Swm 
380 385 390 395 400 
0 
0.1 
0.2 
0.3 
0.4 
0.5 
0.6 
0.7 
0.8 
0.9
1 
Time (days) 
Water Saturation; Swf, Swm 
97-1 
97-2 
97-3 
T-7: 0.6m - Swf 
T-7: 3.0m - Swf 
T-7: 0.6m - Swm 
T-7: 3.0m - Swm 
max 
max 
max 
T-8: 0.3m - Swf 
T-8: 0.3m - Swm 
max 
max 
I-3: 0.3m - Swf 
I-3: 1.5m - Swf 
I-3: 1.5m - Swm 
I-3: 0.3m - Swm 

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ANL-NBS-HS-000007 RE V00 62March 2000 
6.5.1.1.5.2 Three-Dimensional Model Simulation 
Following the calibration of the one-dimensional columns extracted from the site model, the full 
three-dimensional site model was used to examine infiltration front arrival times in boreholes E-4 
and T-4. These boreholes had sampling points with both minimum and maximum times and were 
outside the perimeter of the infiltration pond. Hence, the full three-dimensional infiltration front 
extending from beneath the pond was simulated in order to capture the lateral migration of the 
infiltrating water to these observation points. Use of the full three-dimensional model serves as 
confirmation regarding the applicability of parameters obtained during the calibration with the 
one-dimensional columns. 
Figure 6-16 shows the water saturation distribution in the fracture continuum of the 
three-dimensional dual-permeability model at the start of the 97-2 infiltration test. Within the 
dimensionless depth interval of 0.0 to 0.2, the water saturation directly beneath the pond is 
approximately 0.24, while the ambient background water saturation is 0.18. The elevated water 
saturation distribution resulting from the 97-1 test diminishes as depth increases. Of particular 
note is the fact that the water saturation distribution has a relatively uniform lateral distribution at 
each depth interval and is not closely associated with the observed fracture continuum nodes 
indicated on Figure 6-5. The cause of this last observation will be explained shortly. 
Figure 6-17 shows the water saturation distribution in the fracture continuum at 0.9 days into the 
97-2 infiltration test (388 days since 96-1). This time was chosen because it roughly coincided 
with the arrival time of the infiltration front for sampling depths between 3.0 m and 6.0 m from 
the one-dimensional analysis. These depths are in the range of sampling depths in boreholes E-4 
and T-4. The simulated region of elevated water saturation due to the infiltrating water is quite 
uniform both laterally and vertically. The uniform vertical shape is consistent with the 
one-dimensional simulations where there was very little time lag between the arrivals of the 
infiltration front with depth, indicating that the infiltration front traveled rapidly through the 
fracture continuum. The uniform lateral shape of the infiltration front indicates that the inferred 
fracture pattern shown on Figure 6-5, along with the zonal distribution of hydrogeological 
parameters in the upper basalt, had little influence on preferential flow of infiltrating water 
through the fracture continuum. This may be a consequence of insufficiently large permeability 
contrasts as a result of the choice of weighting factors for the fracture continuum. Alternatively, 
application of the measured infiltration rate equally to all nodes within the infiltration pond, 
regardless of the inferred fracture pattern or ground elevation within the pond, may have biased 
the model to create the uniform infiltration pattern.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 63 March 2000 
DTN: LB990930123122.002 
Figure 6-16. Water Saturation Distribution in the Fracture Continuum at the Start of the 97-2 Infiltration 
Test  387.1 Days Since the Start of 96-1 
50 55 60 65 70 
55 
60 
65 
70 
(b) 0.2 - 0.4 
50 55 60 65 70 
55 
60 
65 
70 
Easting (m) 
Northing (m) 
(c) 0.4 - 0.6 
50 55 60 65 70 
55 
60 
65 
70 
0.24 
0.22 
0.2 
0.18 
0.16 
0.14 
0.12 
0.1 
0.08 
0.06 
0.04 
0.02 
0 
Easting (m) 
(d) 0.6 - 1.0 
Sw fractures 
50 55 60 65 70 
55 
60 
65 
70 
Northing (m) 
(a) 0.0 - 0.2 
T-4 
E-4

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 64 March 2000 
DTN: LB990930123122.002 
Figure 6-17. Water Saturation Distribution in the Fracture Continuum 0.9 Days into the 97-2 Infiltration 
Test  388.0 Days Since the Start of 96-1 
Figure 6-18 shows the water saturation distribution 2.9 days (390 days since 96-1) into the 97-2 
infiltration test. This time was chosen because it roughly coincides with rapid decline in water 
saturation at the end of the 97-2 infiltration test, which occurred over a 2.08 day period. Once 
again, the lateral extent of the saturation distribution appears uniform with depth, with no 
preference given to the observed fracture network. Figure 6-17 shows the water saturation 
distribution before the minimum expected time of the infiltration front for E-1 at a vertical depth 
of 1.5 m and T-4 at vertical depths of 0.6 m and 5.8 m. Figure 6-18 shows the water saturation just 
after the maximum expected arrival time of the infiltration front for both T-4 sampling intervals 
and within the time window for the arrival at E-1. Figure 6-17 shows that the initial rapid 
advection of the infiltration front is restricted to a one-dimensional flow path directly beneath the 
pond and misses boreholes T-4 and E-1. Capillary forces do cause lateral migration of the 
infiltration front by 2.9 days after 97-2, which is consistent with bromide tracer samples obtained 
from the site. 
50 55 60 65 70 
55 
60 
65 
70 
(b) 0.2 - 0.4 
50 55 60 65 70 
55 
60 
65 
70 
Easting (m) 
Northing (m) 
(c) 0.4 - 0.6 
50 55 60 65 70 
55 
60 
65 
70 
0.8 
0.75 
0.7 
0.65 
0.6 
0.55 
0.5 
0.45 
0.4 
0.35 
0.3 
0.25 
0.2 
0.15 
0.1 
0.05 
0 
Easting (m) 
(d) 0.6 - 1.0 
Sw fractures 
50 55 60 65 70 
55 
60 
65 
70 
Northing (m) 
(a) 0.0 - 0.2 
T-4 
E-4

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6.5.1.1.6 Summary and Conclusions of Box Canyon Study 
The hydrogeological system at Box Canyon was simulated using TOUGH2 (TOUGH2 V1.3, 
STN: 10061-1.3-00, Version 1.3). This involved the application of the dual-permeability 
formulation to represent both water and air flow through the variably saturated, fractured basalt 
present at the site. The modeling approach was adapted from the methodology used to simulate 
flow and transport processes in unsaturated rocks at Yucca Mountain (Bandurraga and 
Bodvarsson, 1999; Doughty, 1999). Construction of the conceptual model involved subdividing 
the upper basalt flow into zones based upon the vertical columnar fracture spacing. We used 
sampling points within the boreholes that indicated active flow of water during the infiltration 
tests to infer a network of active water-conducting fractures. This network was used to bias 
hydrogeological properties of the fracture continuum nodes of the model to channel infiltrating 
water to places where it was observed to flow. 
DTN: LB990930123122.002 
Figure 6-18. Water Saturation Distribution in the Fracture Continuum 2.9 Days into the 97-2 Infiltration 
Test  390.0 Days Since the Start of 96-1 
50 55 60 65 70 
55 
60 
65 
70 
(b) 0.2 - 0.4 
50 55 60 65 70 
55 
60 
65 
70 
0.25 
0.24 
0.23 
0.22 
0.21 
0.2 
0.19 
0.18 
0.17 
0.16 
0.15 
Easting (m) 
(d) 0.6 - 1.0 
Sw fractures 
50 55 60 65 70 
55 
60 
65 
70 
Easting (m) 
Northing (m) 
(c) 0.4 - 0.6 
50 55 60 65 70 
55 
60 
65 
70 
Northing (m) 
(a) 0.0 - 0.2 
T-4 
E-4

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Calibration of the model proceeded in two stages. First, the permeability of the fracture 
continuum nodes was adjusted to reflect the pressure response from pneumatic tests conducted at 
the site. Second, arrival times of the infiltration front as inferred from the bromide tracer data 
were used to calibrate the fracture continuum porosity, matrix continuum permeability, and 
fracture-matrix continua interfacial area. Calibration results indicated that the fracture continuum 
porosity was a very sensitive parameter controlling the arrival time of the infiltration front. The 
fracture continuum porosity of the upper basalt flow was scaled by a factor of 50 relative to that 
calculated using the aperture from the permeability calibration. The matrix continuum 
permeability was increased by a factor of 4.5 relative to the core measurements to reflect the 
influence of the highly permeable vesicular zones on the field scale. Finally, the fracture-matrix 
continua interfacial areas were multiplied by a factor of 0.01. This caused the 97-1 infiltration 
pulse to be completely absorbed from the fracture into the matrix continuum at a shallow depth 
while permitting the 97-2 infiltration pulse to advect rapidly to a greater depth. The 97-1 and 97-2 
infiltration tests were the first two in the 97 series of infiltration tests. Physically, the choice of 
interfacial scaling area scaling factor is justified by the decreased contact area of the water phase 
between the fracture and matrix resulting from the channelized flow of the infiltrating water 
through the variably saturated fractures. The physical rationale for increasing the porosity given 
the channelized flow of water in the fracture continuum may be a consequence of multiple factors 
resulting from the rough-walled nature of the fracture surfaces, such as flow of water into 
dead-end fracture channels, and the tortuous flow paths of water rivulets within the rough-walled 
fracture plane. 
Simulation of the three-dimensional infiltration front indicates that it is relatively uniform both 
laterally and vertically. It shows little if any influence from either the zoned distribution of 
hydrogeological parameters in the upper basalt or the fracture network that was meant to channel 
the flow of infiltrating water. This may be a consequence of distributing the water that was 
observed to infiltrate from the pond during the various infiltration tests equally to all surface 
nodes within the perimeter of the pond. Alternatively, the bias applied to the fracture nodes may 
have provided an insufficient permeability contrast to preferentially channel the infiltrating water 
as expected. 
Parameter estimation for both the pneumatic and infiltration tests was conducted manually. This 
calibration method was adopted to provide a preliminary interpretation of the expected range in 
these parameters. The scaling factors employed during calibration imply a bias indicating 
inaccuracies in applying the conceptual model as discretized to represent flow processes 
controlling water infiltration in variably saturated fractures. In general, a consistent set of 
parameters was obtained which allowed the dual-permeability model to replicate the field data. 
Although the dual-permeability approach is also applied to explain groundwater flow at Yucca 
Mountain, the vastly different scales of Box Canyon and Yucca Mountain imply that upscaling is 
an issue when comparing parameter values. 
6.5.1.2 Rainier Mesa 
Rainier Mesa is located approximately 20 miles to the northeast of Yucca Mountain, Nevada. The 
area contains a number of tunnels that were excavated for the underground nuclear weapons 
testing program. Before construction of the Exploratory Studies Facility (ESF), the hydrogeologic

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data collected at Rainier Mesa provided the only extensive underground observations in tuff units 
similar to those of Yucca Mountain. 
Rainier Mesa is situated at a higher elevation than Yucca Mountain and has a mean annual 
precipitation of ~320 mm/yr, approximately double the Yucca Mountain mean (Wang et al. 1993, 
p. 676). About eight percent of the measured Rainier Mesa mean precipitation was observed to be 
infiltrating into one of the tunnels constructed in zeolitic tuffs at the Rainer Mesa site. The 
seepage was associated with a small number of faults and fractures (Wang 1991, p. 79). These 
structural features are thought to be a pathway for flow from perched water above the zeolitic 
horizon (Wang 1991, p. 82). The seepage is geochemically similar to meteoric water (Wang et al. 
1993, p. 677). Tracer tests and tritium samples indicate that the likely rate of fast pathway flow is 
from one to six years to reach from the surface to the water table at a depth of 1000 m. The travel 
time is orders of magnitude less than the matrix travel time calculated using measured matrix 
sample conductivities. This observation is supported by measurements of bomb-pulse 36Cl in 
several samples from one of the tunnels (Wang et al. 1993, p. 677). 
The stratigraphy of both Rainier Mesa and Yucca Mountain consists of alternating welded and 
nonwelded tuffs. The zeolitic Tunnel Bed tuffs at Rainier Mesa show a range of mineral 
compositions similar to those in the Calico Hills nonwelded (CHnz) tuff at Yucca Mountain 
(Wang et al. 1993, p. 676). Also, the higher Rainier Mesa mean precipitation is similar to the 
long-term average predicted for Yucca Mountain (DOE 1998, p. 2-28). However, the relative 
thicknesses of the welded and nonwelded tuff units at the two sites differ significantly (Figure 
6-19). Below the welded tuff caprock at Rainier Mesa lies the approximately 150-meter-thick 
nonwelded Paintbrush Tuff (PTn). The bottom third of this unit is extensively zeolitized due to 
hydrothermal alteration of the tuff shortly after its emplacement. At Yucca Mountain, the PTn is 
mostly vitric, with thin localized lenses of clays and zeolites. Seepage at Rainier Mesa occurs 
only in tunnels constructed in the zeolites; for the tunnel constructed in nonwelded, non-zeolitized 
tuff, no seepage is observed.

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Figure 6-19. Comparison of Hydrogeologic Stratigraphic Sections of Rainier Mesa and Yucca Mountain 
(Wang et al. 1993, p. 675) 
Tuff matrix permeabilities at Rainier Mesa are reported (Wang et al. 1993) to be several orders of 
magnitude higher than those of corresponding units at Yucca Mountain. Since the tuffs at the two 
sites have similar origins, mineralogy, and porosity, there is no apparent reason why their 
permeabilities should be different. Wang et al. (1993, p. 676) suggested that the differences could 
be an artifact of different measurement methods. Now that extensive matrix permeability data are 
available for Yucca Mountain tuffs, this issue could be readily resolved by repeating the 
permeability measurement procedure on Rainier Mesa samples. 
In spite of differences in thickness of stratigraphic units and reported permeabilities, Rainier Mesa 
provides one of the best opportunities to study a number of processes analogous to Yucca 
Mountain. These include episodic pulses, such as those that affect the PTn; flow patterns and 
percolation fluxes based on geochemical signatures; seepage into drifts; and sorption in vitric and 
zeolitic units. A substantial body of data already exists that could be applied in the Yucca 
Mountain UZ flow and transport model to evaluate seepage and percolation under wetter climate 
scenarios. Additional tests would have to be conducted to evaluate sorption and retardation 
processes. An aspect of the Rainier Mesa site that affects its suitability as an analog is the 
perturbation by nearby underground nuclear weapons testing that may have affected the PTn and 
increased the number of structural features that act as fast flow pathways. This effect would need 
to be evaluated before the Rainier Mesa data are used to develop important conclusions about 
long-term predictions of Yucca Mountains response to thermal and climate perturbations. 

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ANL-NBS-HS-000007 REV00 69 March 2000 
6.5.1.3 Other Flow and Seepage Analogs 
In addition to the Box Canyon and Rainer Mesa sites, other locations may be suitable as analogs 
to infiltration and flow processes at Yucca Mountain. One that has already been used in Yucca 
Mountain analyses is the U.S. Nuclear Regulatory Commissions (NRC) Apache Leap site in 
Arizona. Saturated and unsaturated flow parameters from tuff at the site were compared to Yucca 
Mountain data (Wang 1992). Based on the differences between the flow parameters of the tuffs 
for the Yucca Mountain and Apache Leap sites, a relationship between pore-size distribution 
index and saturated permeability was developed. The relationship could be applied to test its 
utility in scaling hydrologic parameters of faults or fractures at Yucca Mountain, based on 
measured data from other sites. 
6.5.2 Analogs to UZ Transport of Radionuclides 
Section 6.5.2.1 discusses previous and new work at Pea Blanca, Mexico as an analog to UZ 
transport of radionuclides. Section 6.5.2.2 considers a variety of sites in northwestern Nevada 
and their potential application as analogs to UZ flow and transport at Yucca Mountain. 
6.5.2.1 Natural Analog Studies at Pea Blanca, Mexico 
6.5.2.1.1 Introduction 
Section 6.5.2.1 provides a summary of the analysis of data from previous Pea Blanca studies 
relevant to source term issues and to radionuclide retention in the UZ. This analysis includes a 
bibliography (Attachment III) of existing studies regarding alteration of uraninite, flow pathways 
for radionuclides, periods of radionuclide migration, and their degree of retention in the Pea 
Blanca flow system. Subsections 6.5.2.1.2 and 6.5.2.1.3 provide the geologic setting of Pea 
Blanca and the historical context of previous analog studies. Subsection 6.5.2.1.4 discusses both 
previous studies that utilized the uranium-series disequilibrium approach and new analyses 
conducted by the Yucca Mountain Project in 1999, as well as conclusions based on the new work. 
Subsection 6.5.2.1.5 summarizes supplemental hydrologic studies that were conducted previously 
and that could be built upon through recommendations made in Subsection 6.5.2.1.6 to obtain a 
more complete three-dimensional picture of actinide transport at Pea Blanca for the purpose of 
building confidence in understanding similar potential transport processes at Yucca Mountain. 
6.5.2.1.2 Background 
The Yucca Mountain site is located in silicic tuffs of Miocene age, in an arid, oxidizing 
environment with the potential emplacement horizon hundreds of meters above the saturated 
zone. In the 1980s, Goodell and others recognized the significance of the Pea Blanca uranium 
deposits in the Mexican State of Chihuahua as natural analogs for the potential repository at 
Yucca Mountain (Goodell 1985; Murphy 1995). In the 1970s, the Pea Blanca region was a major 
target of uranium exploration and exploitation by the Mexican government. Since that time the 
Nopal I uranium deposit has been extensively studied by researchers in the U.S. and Europe 
because it is a good analog for evaluating the fate of spent fuel, associated actinides, and fission 
products at a geologic repository. A bibliography of studies associated with Pea Blanca is part of 
this report (Attachment III).

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The Nopal I uranium deposit at Pea Blanca represents an environment that closely approximates 
that of the potential high-level radioactive waste repository at Yucca Mountain, Nevada in the 
following ways: 
 Climatologically: both are located in semi-arid to arid regions. 
 Structurally: both are part of a basin and range horst structure composed of Tertiary 
rhyolitic tuffs overlying carbonate rocks. 
 Hydrologically: both are located in a chemically oxidizing, unsaturated zone 100 meters 
or more above the water table. 
 Chemically: the alteration of uraninite to secondary uranium minerals at Nopal I may be 
similar to the eventual fate of uranium fuel rods in a potential geologic repository like 
Yucca Mountain. 
6.5.2.1.3 Geology 
The Pea Blanca uranium district is located approximately 50 km north of Chihuahua City, 
Mexico, in the northern part of the Sierra Pea Blanca (Figure 6-20). The region is part of the 
Chihuahua tectonic belt, which is characterized by Laramide-age northwesterly vergent folds and 
thrust faults in Mesozoic and lower Tertiary rocks. A regionally extensive sequence of Tertiary 
volcanic rock unconformably overlies the older units. The region was affected by 
north-south-trending normal faulting that is thought to be the southern manifestation of the Rio 
Grande Rift tectonism. North-south oriented basin and range topography now characterizes the 
region (Goodell 1985). 
6.5.2.1.3.1 The Pea Blanca District 
The Sierra Pea Blanca is a north-south trending, westerly-tilted basin and range-style horst 
block. The uranium deposits are located close to the eastern edge of the block (Pearcy et al. 1995). 
The oldest rocks in the vicinity of the Pea Blanca district are Early to Late Cretaceous reef, 
back-reef and basinal, thinly bedded to massive limestone. The limestone is unconformably 
overlain by a sequence of Tertiary volcanic and lesser sedimentary rocks. From older to younger, 
these Tertiary units are the Pozos conglomerate and rhyolitic ignimbrite of the Corrales, 
Coloradas, Nopal, and Escuadra Formations. The Piloncillos fanglomerate locally separates the 
Nopal and Escuadra Formations. The Nopal Formation was dated at 44 Ma (million years). (K-Ar 
age, Alba and Chavez 1974; Pearcy et al. 1995). 
The Pea Blanca uranium district consists of three exploration camps: El Nopal, Margaritas, and 
El Cuervo. Many of the uranium deposits in the district have been drilled or developed by 
underground or open-pit mining over a period of 20 years, but there has been no mining activity at 
Pea Blanca since 1985. Combined, these deposits contained more than 2,000 metric tons of 
U3O8 and constitute the bulk of Mexican uranium sources. The deposits occur close to the eastern 
edge of the Sierra Pea Blanca range and, in general, are concentrated in the lower part of the

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ANL-NBS-HS-000007 REV00 71 March 2000 
Tertiary volcanic section. Uranium mineralization locally extends downward into the upper part 
of the Cretaceous limestone (see Figure 6-21). 
Figure 6-20. The Nopal I Uranium Deposit in the Pea Blanca Mining District, Chihuahua, Mexico. 
Yucca Mountain is located northwest of the Pea Blanca district along a general trend of 
Tertiary volcanic rocks in the Basin and Range province (from Pearcy et al. 1994, p. 715) 
6.5.2.1.3.2 The Nopal I Deposit 
Nopal I is a small, high-grade uranium deposit located in a highly brecciated zone that occurs at 
the intersection of two steep faults (Figure 6-21). The Nopal I deposit is interpreted to have 
formed by hydrothermal solutions that precipitated uraninite (nominally UO2+x) as they moved 
through a subvertical, highly fractured zone within welded silicic tuff (Pearcy et al. 1994, p. 714). 
The Nopal I deposit is nearly cylindrical, having rough horizontal dimensions of 18 m by 30 m 
with a nominal ore zone extending approximately 100 m vertically (Pearcy et al. 1995, p. 685) 
(Figure 6-21). Currently, about 300 metric tons of oxidized uranium remains on site. The upper, 
highest-grade portion of the deposit is hosted by heavily fractured, silicic tuffs of the Nopal and 
Coloradas Formations. The deposit extends into the underlying Pozos Formation, although the 
grade decreases significantly. In the vicinity of the ore body, the Nopal Formation is a densely 
welded crystal-lithic rhyolitic tuff with phenocrysts of quartz, sanidine, and biotite. A highly

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ANL-NBS-HS-000007 RE V00 72March 2000 
altered vitrophyre occurs at the base of the formation. The Coloradas Formation is a lithic-crystal, 
densely welded tuff with phenocrysts of quartz, sanidine, plagioclase, and biotite. 
Figure 6-21. Orthogonal, Vertical Cross Sections of the Nopal I Deposit Illustrating Its Location above 
the Water Table and Within Silicic Tuffs of the Nopal and Coloradas Formations and the 
Basal Conglomerate of the Pozos Formation (from Pearcy et al. 1994, p. 716) 
Uraninite occurs only very locally in highly silicified pods near the center of the ore body. The 
uraninite is interpreted to be part of a relict ore assemblage that was altered by oxidizing fluids 
that produced a secondary suite of uranyl oxy-hydroxides (schoepite) and uranyl silicates 
(uranophane) (Pearcy et al. 1994). Uranophane is the most abundant ore mineral but at least seven 
other uranium-bearing minerals have been identified (Pearcy et al. 1994, Table 2). Uranophane 
occurs as euhedral needles as well as granular masses in highly oxidized zones that are also 
enriched in kaolinite, limonite and chalcedony. The sequence of U-bearing oxidation products 
observed at Nopal I (uraninite- schoepite- uranophane) is very similar to those produced in 
laboratory experiments with uranium oxide exposed to oxidizing conditions in the presence of 
simulated groundwater (Wronkiewicz et al. 1996). 
Finally, uranium-rich caliche located at the elevation of the deposit and about 3 m outside the 
limit of U mineral occurrence has been dated by U-series isochron techniques at 53.6  0.8 ka 
(thousand years), suggesting that weathering of the deposit has been the dominant mode of 
alteration for at least that period (Pearcy et al. 1994, p. 714).

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 73 March 2000 
6.5.2.1.4 Characterization of Radionuclide Transport Using U-Series Disequilibria 
6.5.2.1.4.1 Previous Work 
Studies of U-series disequilibria within and around uranium deposits can provide valuable 
information on the timing of actinide mobility and hence the undisturbed stability of a potential 
repository over the geologic time scales associated with the required lifetime of the facility. The 
theory underlying this technique is discussed in Section 6.5.2.1.6.3. This section summarizes 
studies that have examined uranium transport through fractures within and outside the Nopal I 
deposit. The interested reader is referred to Attachment III, which contains a bibliography, for a 
more extensive list of radionuclide migration studies of Pea Blanca. 
6.5.2.1.4.1.1 Center for Nuclear Waste Regulatory Analyses Work 
The Center for Nuclear Waste Regulatory Analyses (CNWRA) at the Southwest Research 
Institute, with support of the NRC, has conducted numerous and varied studies with the goal of 
using Pea Blanca as an analog to Yucca Mountain. 
Leslie et al. (1993) and Pearcy et al. (1994) compared the alteration of uraninite from Nopal I to 
laboratory experiments of degradation of spent nuclear fuel at Yucca Mountain, Nevada. They 
found that uraninite from the Nopal I deposit should be a good natural analog to spent nuclear fuel 
because long term experiments on spent fuel show alteration parageneses, intergrowths, and 
morphologies that are remarkably similar to those observed at Nopal I. Oxidation of the uraninite 
at Nopal I has produced an ordered suite of minerals, first forming uranyl oxide hydrates followed 
by uranyl silicates. Consistent with a high calcium abundance in Nopal I, the dominant secondary 
uranium phase is uranophane, a calcium uranyl silicate. In comparison, laboratory experiments 
find that the general trend is to form mixed uranium oxides, then uranyl oxhydroxides, then 
finally uranium silicates, mostly uranophane with lesser amounts of soddyite (Wronkiewicz et al. 
1996). Finally, uraninite at Nopal I has a low trace element component (average of 3 wt %) that 
compares well with that of spent nuclear fuel (typically < 5 wt %). 
In an effort to determine the relative mobility of uranium along mesofractures (>1 mm and longer 
than 10 m  Pearcy et al. 1995, p. 693), microfractures (< 1 mm), and matrix at Nopal I, Pearcy et 
al. (1994, 1995) mapped and sampled portions of Levels +10 (originally 5 10 meters below 
surface before mining operations) and +00 (10 m lower than level +10) of the Nopal I deposit. 
Approximately 1200 m2 for level +10 and 200 m2 for level +00 were painstakingly cleared of 
loose rocks, soil, and debris. A 1 m  1 m grid with axes oriented NS and EW was constructed 
over the two cleared areas and referenced to this framework (see Figure 6-22). Fracture mapping 
was carried out at a scale of 1:25 and includes 11,374 individual fractures. On Figure 6-22, the 
visible uranophane line indicates the limit of visible U mineralization and marks the nominal edge 
of the deposit. The intent of this figure is to note the fine degree of detail in which fracture 
locations have been mapped. Examination of the distribution of U in the host tuff at scales ranging 
from 10 -6 to 10 m indicates that, outside the primary deposit, U occurs mainly along fractures in 
secondary minerals (and iron hydroxides, oxides, and silicates). Major conclusions from this work 
(Pearcy et al. 1995), based on both field study and 234U analyses, include:

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 74 March 2000 
 Transport of U away from the deposit occurred mainly along fracture paths. 
 Transport along mesofractures occurred at 20 times greater distance (up to 30 m) than 
along microfractures. 
 Mobilization of U from the deposit occurred within the last 1 Ma (million years). 
 Matrix transport was limited to distances of <1 mm. 
Figure 6-22. Fracture Map of the Nopal I Deposit (from Pearcy et al. 1995, Figure 3). Perimeter Scale is 
in Meters

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 75 March 2000 
Prikryl et al. (1997) reported electron microprobe analyses of U concentration in fracture filling 
minerals, as well as 238U-234U-230Th alpha spectrometry data on bulk fracture samples from the 
major E-W trending fracture at 13.5 m N (fracture B). The microprobe results for goethite, 
hematite, and amorphous Fe-oxyhydroxide minerals and bulk samples indicate that there are 
strong mineralogic and spatial controls on the distribution of U in this fracture. Uranium 
concentrations in bulk fracture materials and in goethite and hematite minerals show a decreasing 
trend away from the ore body. This trend suggests that U was mobilized and transported away 
from the deposit, most likely by episodic infiltration of meteoric water. Analysis of uranium 
content at any sample location along the fracture reveals that goethite has a higher U 
concentration than hematite. This indicates that either uranium has a greater affinity for goethite 
or that uranium was more enriched in solutions during goethite formation. Uranium and thorium 
isotopic data on the 13.5 m N fracture (Fracture B) also revealed a 234U/238U ratio greater than 
unity, both within and outside the deposit. This suggests that U mobilization was relatively recent 
(< 1 Ma) and is related to uptake of U from fracture fluids that carried excess 234U. Variations in 
234U/238U were interpreted as due to a multistage mobilization process. 230Th/234U activity ratios 
greater than unity were interpreted as due to either 1) 234U loss after 230Th ingrowth, or 2) 
preferential sorption of 230Th by fracture-filling minerals from solution. 
Pickett and Murphy (1997) obtained additional 238U-234U-230Th data for other fractures at Nopal 
I. Both bulk analyses and results of sequential extractions on fracture-filling materials were 
reported. They found that most of the data for fracture-filling materials lie in the forbidden 
zone, which is the region on a Concordia plot where there is no finite single-stage age solution 
(see Section 6.5.2.1.4.2.2). This observation led these authors to invoke multiple U mobilization 
events involving both enrichment and removal over the past few hundred ka to explain these data. 
The sequential extraction data were also complex. Data for crystalline iron-oxides and resistates 
were similar to the bulk rock systematics. However, amorphous iron oxyhydroxides were 
interpreted to be older than bulk rock, and adsorbed or ion exchangeable surface sites were 
suggested to be younger than bulk rock. They interpreted the 238U-series as well as U/Pb isotopic 
systematics in terms of U mineral history and the nature and timing of U transport at Pena Blanca. 
They analyzed three samples of uranophane which gave 238U/206Pb and 235U/207Pb internal and 
external isochron ages of 3.4 and 3.2 Ma, respectively. The isotopic and chemical data indicate the 
following history: 
 Primary uraninite mineralization occurred approximately 8 Ma. 
 Deposition of uranyl silicates occurred during a single period around 3 Ma. 
 Complex episodic U mobilization and remobilization, including dispersion of uranium 
via aqueous transport into the surrounding fractured tuff, took place over the past few 
hundred thousand years. 

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 76 March 2000 
6.5.2.1.4.1.2 University of Texas, El Paso Work 
Wong (1998) completed a study of uranium-series disequilibria utilizing gamma spectrometry for 
fracture-infilling materials at Nopal I. Samples were collected from various fractures both within 
and outside the deposit including the large fracture (B) at 13.5 m N. Mineralogy of these samples 
was also determined by x-ray diffraction. The 230Th/238U and 226Ra/230Th activity ratios ranged 
from 0.58-1.74 and 0.85-1.54, respectively (Wong, 1998, pp. 87, 93). Samples with higher U 
concentrations within the deposit had more limited ranges in 230Th/238U and 226Ra/230Th with 
activity ratios of ~1.0-1.1 and 0.8-1.1, respectively. Because these are gamma spectrometry data, 
estimated errors are fairly large, +/- 10% or more. Consequently, it is difficult to draw strong 
conclusions from these data. However, the observations of disequilibria for both 230Th/238U and 
226Ra/230Th led Wong to conclude that there had been open system behavior for these nuclides, 
within the past 8 ka for Ra/Th and within the past 300 ka for Th/U. 
6.5.2.1.4.1.3 University of Paris Work 
Electron paramagnetic resonance has been used at Pea Blanca to detect radionuclide migration. 
An example of one such study is Allard and Muller (1998), who tested the potential use of point 
defect centers (essentially radiation damage from absorbed dose) in kaolinite to detect U 
mobilization. They compared integrated defects to current uranium distribution to infer the past 
distributions of uranium at Pea Blanca. This investigation indicated two major migration events: 
 Past accumulation of U outside the mineralized zone followed by leaching; 
 A late-stage accumulation of uranium in the area of the primary uranium deposit. 
6.5.2.1.4.2 Recent Work by YMP 
Studies of U-series disequilibrium within and around uranium deposits can provide valuable 
information on the timing of actinide mobility over the geologic time scales associated with the 
required lifetime of a potential repository. Prior studies at Pea Blanca, summarized in 
Section 6.5.2.1.4.1, have focused on the extent and timing of uranium-series mobility or transport 
at this site and concluded open system behavior suggesting mobility of uranium and its daughter 
products. Previous U-series thermal ionization mass spectrometry (TIMS) work at the Nopal I 
deposit in Pea Blanca done by Los Alamos National Laboratory (LANL) for the YMP (Murrell 
et al., 1997) found closed system behavior suggesting very limited mobility in fracture-filling 
material for U, Th, and Pa for the last 100 to 400 ka. However, these results and conclusions were 
in contrast to decay-counting data for the same samples obtained by the CNWRA and their 
conclusion of open-system U behavior (Pickett and Murphy, 1997). 
In an effort to settle these apparent discrepancies and to learn the true extent of uranium mobility 
at Pea Blanca, the YMP analyzed 18 additional samples for 238U-234U-230Th-266Ra and 
235U-231Pa in four prominent uranium mineralized fractures. The relevant decay series are as 
follows:

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 77 March 2000 
6.5.2.1.4.2.1 Analytical Method 
We measured 238U-234U-230Th-226Ra and 235U-231Pa in 18 samples from fractures that emanate 
from the primary U-bearing zone of the deposit. These samples were obtained from the CNWRA. 
Sample locations are shown in Figure 6-23. A photograph showing the E-W fracture (Fracture B, 
13.5 m N) is shown in Figure 6-24. 
The samples consisted of splits of powders (labeled whole rock (WR) or powdered (PWD) on 
Table 6-10) prepared by the CNWRA, or hand specimens provided by the CNWRA. Hand 
specimens are labeled hand sample or previous (if reported by Murrell et al. (1997)) on 
Table 6-10. Fracture-filling materials were removed from the hand samples in the LANL 
laboratory for analysis. For the samples prepared in the laboratory, approximately 100 grams of 
material from each hand specimen were subdivided with a chisel into tuff and fracture-filling 
mineral fractions of <1 cm size. The fracture-filling mineral fractions of 5-10 g were then 
homogenized and powdered with a mortar and pestle, and aliquots of 0.5-1 g were taken for 
U-series analysis. Sample replicates, standard reference ore BL-4 supplied by the Canadian 
Certified Reference Material Program, geologic reference Table Mountain Latite (TML) supplied 
by the University of California at Santa Cruz, and blanks were also analyzed. 
The aliquots were dissolved in Teflon vials with hydrochloric, hydrofluoric, nitric, and perchloric 
acids. After treating insoluble fluorides with boric acid, samples were redissolved in 1M (molar) 
nitric acid and centrifuged to verify complete dissolution. Samples were then quantitatively 
transferred, and 1M nitric acid stock solutions were prepared in 1-liter polyethylene bottles. 
Aliquots were spiked with 233,236U tracer and 229Th tracer. Uranium and Th were separated by 
standard anion exchange methods. The U fractions were loaded onto Ta-Re-Ta triple filaments 
and the Th fractions were loaded onto Re-Re double filaments. These were analyzed in a Sector 
54-WARP thermal ionization mass spectrometer (TIMS). 
For measurements of 226Ra and 231Pa, separate aliquots equal in mass to the Th and U aliquot 
were taken and spiked with 228Ra tracer and 233Pa tracer. The Ra fraction was separated by 
standard cation exchange methods, including a large column for Ra-Ba isolation and small EDTA 
columns for Ra/Ba separation. The Pa fraction was separated using Eichrom TRUSpec resin, 
followed by anion exchange columns for Pa/U separation. The Ra fraction was loaded on a Re 
filament with silica gel and analyzed in the Sector 54-WARP instrument. The Pa fraction was 
238U(t=4.47x109 y) 234U(t=2.45x105 y) 230Th(t=7.54x104 y) 226Ra(t=1600 y) 
206Pb 
235U(t=7.04x108 y) 231Pa(t=3.28x104 y) 207Pb 
232Th(t=1.41x1010 y) 228Ra(t=5.77 y) 208Pb

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 78 March 2000 
loaded on a carburized Re filament and analyzed in a NBS 12-90 TIMS. Results for replicates and 
geologic standards agreed within the quoted uncertainties (see Table 6-10). Most importantly, the 
results for the geologic standards returned secular equilibrium activity ratios for U-Th and U-Pa 
(Th-Ra for standards and some samples have yet to be analyzed) indicating that the needed 
analytical accuracy was obtained (see Table 6-10). Blanks are negligible in comparison with the 
amounts of these elements in the samples.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 79 March 2000 
Table 6-10. Summary of Results for Fracture and Reference Materials. 
Sample Fracture Th (+/-) U (+/-) Th/U (+/-) (238U)/ 
(232Th) 
(+/-) 
230Th/ 
232Th 
x10-6 
(+/-) (230Th)/ 
(232Th) 
(+/-) 
234U/238U 
x10-6 (+/-) (234U)/ 
(238U) 
(+/-) (230Th)/ 
(234U) 
(+/-) (234U)/ 
(232Th) 
(+/-) (230Th)/ 
(238U) 
(+/-) (231Pa)/ 
(235U) 
(+/-) (226Ra)/ 
(230Th) 
(+/-) 
(ppm) (%) (ppm) (%) (wt.) (%) (%) (ppm) (%) (%) (ppm) (%) (%) (%) (%) (%) (%) (%) 
TML-97B-1 std 30.461 0.36 10.899 0.09 2.795 0.37 1.089 0.37 5.862 0.36 1.093 0.36 54.959 0.14 1.000 0.14 1.003 0.53 1.089 0.39 1.003 0.51 NA NA NA NA 
TML-97B-2 std 30.623 0.31 10.885 0.09 2.813 0.32 1.082 0.32 5.810 0.46 1.083 0.46 54.980 0.14 1.001 0.14 1.001 0.58 1.082 0.35 1.001 0.56 1.006 0.76 NA NA 
BL4 std 12.222 0.34 1714.801 0.09 0.007 0.35 426.992 0.35 2290.600 0.90 426.943 0.90 54.963 0.10 1.000 0.10 1.000 0.97 427.121 0.36 1.000 0.97 0.997 0.70 NA NA 
NOPI-309-WR1 F 34.766 0.31 1266.389 0.09 0.027 0.32 110.858 0.32 623.141 0.20 116.147 0.20 59.257 0.13 1.078 0.13 0.971 0.41 119.555 0.35 1.048 0.38 0.984 0.71 0.987 1.29 
NOPI-320-WR1 F 27.595 0.36 424.337 0.12 0.065 0.38 46.799 0.38 140.478 0.29 26.184 0.29 53.839 0.14 0.980 0.14 0.571 0.50 45.856 0.40 0.559 0.47 0.643 0.82 NA NA 
NOPI-376-WR1 C 32.042 0.30 255.831 0.12 0.125 0.32 24.299 0.32 163.315 0.36 30.440 0.36 64.857 0.19 1.180 0.19 1.061 0.52 28.682 0.38 1.253 0.48 NA NA 0.870 1.16 
NOPI-403-WR1 E 38.495 0.34 299.822 0.11 0.128 0.35 23.703 0.35 143.507 0.38 26.748 0.38 57.723 0.16 1.051 0.16 1.074 0.54 24.901 0.39 1.128 0.52 0.993 0.83 NA NA 
NOPI-404-WR1 E 36.379 0.33 131.977 0.08 0.276 0.34 11.041 0.34 73.211 0.80 13.646 0.80 63.990 0.10 1.165 0.10 1.061 0.87 12.858 0.35 1.236 0.87 NA NA NA NA 
NOPI-407-WR1 E 36.687 0.33 444.205 0.14 0.083 0.36 36.849 0.36 189.204 0.24 35.265 0.24 51.806 0.18 0.943 0.18 1.015 0.47 34.743 0.40 0.957 0.43 1.005 0.83 0.754 1.13 
NOPI-410-WR1 E 42.343 0.31 12.659 0.17 3.345 0.35 0.910 0.35 5.839 0.40 1.088 0.40 63.774 0.18 1.161 0.18 1.031 0.56 1.056 0.40 1.196 0.53 0.998 0.77 NA NA 
NOPI-411-WR1 E 36.446 0.36 14.809 0.14 2.461 0.38 1.237 0.38 9.183 0.43 1.712 0.43 73.332 0.16 1.335 0.16 1.037 0.60 1.650 0.41 1.384 0.58 1.003 0.91 NA NA 
NOPI-418 prev B 15.955 0.34 5508.559 0.39 0.003 0.52 1050.733 0.52 6917.074 0.18 1289.266 0.18 65.339 0.20 1.190 0.20 1.031 0.62 1250.501 0.56 1.227 0.59 0.990 0.82 0.989 0.75 
NOPI-419-hand 
sample 
B 28.896 0.36 238.679 0.11 0.121 0.37 25.138 0.37 210.186 0.53 39.176 0.53 81.740 0.14 1.488 0.14 1.048 0.66 37.396 0.40 1.558 0.64 1.001 0.80 0.924 1.24 
NOPI-420-PWD B 26.895 0.32 1303.204 0.14 0.021 0.35 147.468 0.35 930.444 0.16 173.425 0.16 62.339 0.19 1.136 0.19 1.036 0.43 167.470 0.40 1.176 0.38 0.984 0.83 0.839 1.09 
NOPI-421-hand 
sample (LANL) 
B 36.501 0.34 893.188 0.17 0.041 0.38 74.471 0.38 512.600 0.37 95.543 0.37 66.899 0.17 1.218 0.17 1.054 0.56 90.671 0.41 1.283 0.53 NA NA NA NA 
NOPI-421 prev B 36.010 0.34 871.040 0.47 0.041 0.58 73.615 0.58 503.606 0.28 93.867 0.28 66.818 0.20 1.216 0.20 1.049 0.67 89.520 0.61 1.275 0.64 0.993 0.79 0.764 0.65 
NOPI-423-PWD B 49.477 0.35 583.132 0.12 0.085 0.37 35.869 0.37 228.380 0.25 42.567 0.25 63.005 0.19 1.147 0.19 1.035 0.48 41.129 0.42 1.187 0.45 1.002 0.90 NA NA 
NOPI-423-hand 
sample 
B 37.028 0.34 299.824 0.09 0.123 0.35 24.643 0.35 165.206 0.29 30.793 0.29 64.818 0.16 1.180 0.16 1.059 0.48 29.070 0.39 1.250 0.46 0.988 0.73 1.003 1.13 
NOPI-424-hand 
sample 
B 34.996 0.32 61.854 0.09 0.565 0.33 5.389 0.33 34.030 0.51 6.343 0.51 62.753 0.12 1.142 0.12 1.031 0.62 6.148 0.36 1.177 0.61 1.002 0.91 0.975 0.87 
NOPI-425 prev B 34.731 0.32 295.600 0.49 0.117 0.59 25.903 0.59 162.739 0.28 30.333 0.28 62.126 0.20 1.131 0.20 1.036 0.68 29.287 0.62 1.171 0.65 0.997 0.89 0.834 0.84 
NOPI-425-hand 
sample (LANL) 
B 38.048 0.34 127.948 0.11 0.297 0.36 10.234 0.36 63.681 0.30 11.870 0.30 61.357 0.19 1.117 0.19 1.039 0.50 11.428 0.41 1.160 0.47 0.996 0.88 1.121 0.68 
Submitted with this AMR under DTN: LA9909MM122122.001 
Note: This table summarizes the concentration and isotopic data obtained for samples from fractures at the Pea Blanca uranium deposit in Mexico. The data for the isotopes in parentheses are radioactivity ratios. 
NA=not analyzed

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 80 March 2000 
INTENTIONALLY LEFT BLANK

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 81 March 2000 
Figure 6-23. Topographic Map for Nopal I Area (modified from Pickett and Murphy 1997, Fig. 1). The 
figure illustrates the extent of visible uranium mineralization (black shaded area), major 
fractures A-H located near the deposit, sample locations from this study, and proposed 
locations for drilling of near-field groundwater monitoring wells (stars and location marked 
00)

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 RE V00 82March 2000 
Figure 6-24. Photo of the +10 Level of Nopal I. The arrows illustrate the location of the major east-west 
trending fracture B, looking to the east. Most of the samples in this study are from this 
fracture 
6.5.2.1.4.2.2 Uranium and Thorium Isotopic Results 
Results for uranium and thorium isotopes for the samples and standards are shown in Table 6-10. 
Uranium concentrations for the samples generally decrease from the outer margin of the deposit 
to the far end of the fractures, in general agreement with prior studies (Pearcy et al. 1995; Wong 
1998). The absolute concentrations for the powders agree well with the results obtained by Pickett 
and Murphy (1997). However, the U concentration results for the hand samples that we prepared 
are often lower than powders prepared by the CNWRA from the same location. This difference 
indicates less fracture material and more matrix in our samples. 
234U/238U activity ratios are shown in Figure 6-25 and range from 0.94 to 1.49 with a mean of 
about 1.2. There is no obvious systematic spatial trend for these data within the fractures. These 
results are also similar to values reported by Pickett and Murphy (1997). The 234U/238U results 
are generally consistent with an old 234U enrichment (~100-1000 ka; calculated model 234U ages 
from Ivanovich and Harmon 1992, pp. 55-58) produced during dissolution processes and 
preserved in precipitated minerals. However, as can be seen from Figure 6-25, there appears to be 
small-scale post-depositional loss and gain of 234U to the fracture materials that have spread the 
distribution about the mean. 

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 83 March 2000 
(Data in Table 6-10, DTN: LA9909MM122122.001) 
Figure 6-25. Plot of 234U/238U Activity Ratio versus Distance from the Edge of the Deposit for the 
Fracture Samples in This Study (see Table 6-10) 
Figure 6-26 has been modified from Pickett and Murphy (1997) by addition of typical error bars 
and data from Murrell et al. (1997). In this type of plot, known as a Concordia plot, the evolution 
of a closed system through time is shown by the curved arrow labeled time. Most of the data of 
Pickett and Murphy (1997) fall in the forbidden zone, the region of no finite single-stage age 
solution. These values have led Pickett and Murphy (1997) and Wong (1998) to invoke multiple 
U mobilization events involving both U enrichment and removal over the past few hundred 
thousand years to explain their data. The values are a consequence of their higher 230Th/234U and 
variable 226Ra/230Th measurements, which cannot be explained by a simple model of closed 
system evolution. The 230Th/234U activity ratios we observe are generally close to 1 (see Table 
6-10). These values differ significantly from those obtained by Pickett and Murphy (1997). These 
latter values are difficult to discern from secular equilibrium using the decay-counting methods 
employed by previous studies. This difficulty may be the reason for the difference between the 
more precise TIMS data and Pickett and Murphys (1997) results and conclusions. 
6.5.2.1.4.2.3 Uranium-Thorium Ages 
Because the fracture minerals were deposited by aqueous solutions, the ages of the mineral phases 
are related to the timing of the primary fluid flow. Subsequent alteration of these mineral phases 
during more recent fluid movement can also be evaluated using uranium-series disequilibria data. 
As shown in Figure 6-27 (analytical errors are smaller than the points and are <1%), we found that 
the majority of the U-Th data provide finite solutions to the age equation, and while most points 
plot very near the forbidden zone, only two points (NOPI 403 and NOPI 407) actually fall in 
Pena Blanca 234U Plot 
Distance (m) 
0 10 20 30 40 
0.50 
0.75 
1.00 
1.25 
1.50 
1.75 
2.00 
B Fracture 
F Fracture 
C Fracture 
E Fracture 
Secular Equilibrium 
Mean 
(234U) /(238U)

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 84 March 2000 
this area. The data for these two samples are consistent with small amounts of 234U loss. Model 
U-Th ages for the other samples indicate ages of greater than 300 ka (with the exception of a 
discordant sample (NOPI 320) also indicating 234U loss). These model ages are summarized in 
Table 6-11. 
NOTE: Error bars for data of Pickett and Murphy (1997) are typical and have been added to the figure. 
Figure 6-26. Plot of Measurements of 234U/238U versus 230Th/238U for Fracture Filling Materials 
Obtained by the CNWRA (from Pickett and Murphy 1997, Figure 4), with Added Data 
(Identified as LANL) from Murrell et al. (1997).

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 85 March 2000 
DTN: LA9909MM122122.001 
Figure 6-27. Plot of Measurements of (234U)/(238U) versus (230Th)/(238U) for Fracture Filling Materials 
from This Study (Table 6-10) 
The ages in Table 6-11 are calculated using zero initial 230Th in the samples. Because such a 
model is not strictly correct, such ages are upper limits on the true age. This is generally a small 
effect given the high U concentrations in these samples. However, there is a clear correlation 
noted for Fracture B that is related to the Th/U of the sample, with highest ages for samples with 
the lowest authigenic component and greatest Th/U. Since the model ages appear to be noticeably 
affected by the relative abundances of authigenic and non-authigenic components in the samples, 
a correction is needed to obtain an age for only the authigenic component (i.e. true age of 
deposition) (Ivanovich and Harmon 1992, pp. 55-57). Hence, we use the measured Th/U ratios to 
correct the measured 230Th/234U and 234U/238U ratios for the non-authigenic component within 
these samples. This is accomplished by plotting the data in two diagrams consisting of 234U/238U 
versus 232Th/238U, and 230Th/238U versus 232Th/238U (Figure 6-28) (Ludwig and Titterington 
1994). If the samples along the fracture are isochronous, are derived as mixtures of two 
components, and behaved as a closed system, then these plots will yield a linear trend or isochron. 
The y-intercepts of the weighted least square fit of the points correspond to the 230Th/234U and 
234U/238U ratios in the authigenic components of the samples. The program Winfit finds a least 
squares fit with weighting in two dimensions. This is required for the isochron fit. Based on these 
ratios, the calculated age for the authigenic component is 425  80 ka (7 points). Based on this 
age, initial 234U/238U activity ratios are ~2, in reasonable agreement with typical values for 
modern water samples near Nopal I (Pickett and Murphy 1999, Table 2). While this isochron age 
for Fracture B agrees with the uncorrected data from NOPI-418 (39820 ka), the sample with the 
Pena Blanca Th-U Plot 
(230Th)/(238U) 
0 1 2 3 
0
1
2
3 
B Fracture 
F Fracture 
C Fracture 
E Fracture 
(230Th)/(234U) =1 
forbidden zone 
forbidden zone 
NOPI 320 
T = 88 Ka 
(234U) /(238U)

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 86 March 2000 
highest U concentration, the fit is not exact and one point (NOPI 419) is far off the best-fit lines. 
This means that at least one of the model requirements has been violated. 
Table 6-11. U-Th Model Ages 
Sample U-Th Age ka +/- 
NOPI-309-WR1 324 9 
NOPI-320-WR1 88 4 
NOPI-376-WR1 630 120 
NOPI-404-WR1 >780 
NOPI-410-WR1 424 24 
NOPI-411-WR1 342 11 
NOPI-418 p revious39 8 20 
NOPI-419-hand sample 320 9 
NOPI-420-PWD 485 27 
NOPI-421-hand sample (LANL) 461 20 
NOPI-421 p revious43 8 28 
NOPI-423-PWD 464 17 
NOPI-423-hand sample 589 100 
NOPI-424-hand sample 454 34 
NOPI-425 p revious50 0 50 
NOPI-425-hand sample (LANL) 578 100 
Submitted with this AMR under DTN: LA9909MM122122.001 
NOTE: Model assumes zero intial Th and closed system 
behavior since deposition. 
Such assumptions may not be valid for all samples. 
Blank intended.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 87 March 2000 
DTN: LA9909MM122122.001 
NOTE: (234U)/(238U) and (230Th)/(238U) activity ratios for the authigenic components are the y-intercepts 
of the weighted least squares fits. The isochron is calculated from the quotient, (230Th)/(234U). 
Figure 6-28. Diagrams of (234U)/(238U) versus (232Th)/(238U), and (230Th)/(238U) versus (232Th)/(238U) 
for Samples from Fracture B. 
6.5.2.1.4.2.4 Protactinium Isotopic Results 
Results for 231Pa for the samples and standards are shown in Figure 6-29. Analytical errors are 
smaller than the data points and are typically <1%. The 231Pa/235U activity ratios are either at or 
very near secular equilibrium (sample mean = 0.996  0.007). This means that 231Pa-235U (and 
238U since the 238/235 ratios are natural) have behaved as a closed system in the fractures over 
the last 200 ka. From these observations we can conclude that uranium (235, 238) has remained in 
the fractures over the last 200 ka. Based on these results, the mobility of uranium discussed above 
seems limited to the 234U. 
Fracture B 
(232Th)/(238U) 
0.000 0.025 0.050 0.075 0.100 0.125 0.150 
0.00 
0.25 
0.50 
0.75 
1.00 
1.25 
1.50 
1.75 
(230Th)/(234U) = 1.036  0.022 
Age = 425  80 Ka 
Fracture B 
(232Th)/(238U) 
0.000 0.025 0.050 0.075 0.100 0.125 0.150 
0.00 
0.25 
0.50 
0.75 
1.00 
1.25 
1.50 
1.75 
(234U)/(238U) = 1.176 0.0154 
(234U) /(238U) 
(230Th) /(238U)

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ANL-NBS-HS-000007 REV00 88 March 2000 
As can been seen from Figure 6-29, NOPI 320 is younger, with a U-Pa model age of 47  2 ka. 
This sample also has an anomalously low U-Th model age of 88  4 ka. The U-Pa model age is 
similar to U-Th ages for caliche and opal (Pearcy et al. 1995, p. 714) of about 50 ka and may 
indicate enhanced fluid flow at this time. This event caused resetting of sample NOPI 320 but had 
no measurable effect on U (235,238), Th, or Pa mobility in the vast majority of fracture samples. 
The difference in U-Pa and U-Th ages for this sample may be a result of post-depositional loss of 
234U from this sample (but not 235,238U). 
(Table 6-10, DTN: LA9909MM122122.001) 
Figure 6-29. Plot of 231Pa/235U Activity Ratio versus Distance from the Edge of the Deposit for the 
Fracture Samples in This Study 
6.5.2.1.4.2.5 Radium Isotopic Results 
Results for 226Ra/230Th for the fracture samples are shown in Figure 6-30. The 226Ra/230Th 
activity ratios range from 0.7 to 1.1. These results are similar to values reported by Wong (1998, 
pp. 87, 93). The 226Ra/230Th results are consistent with open system Ra behavior over the last 
5 ka. It is useful to point out that the Ra results demonstrate that fluids have occupied the fractures 
over the last 5 ka, which implies that U has had ample opportunity for fluid interactions. It is also 
interesting to note that a variety of plant (Phacelia robusta) growing in the vicinity has very high 
radium contents (Leslie et al. 1999). 
231Pa Plot 
Distance (m) 
0 10 20 30 40 
0.6 
0.7 
0.8 
0.9 
1.0 
1.1 
Standards 
F Fracture 
E Fracture 
B Fracture 
Secular Equilibrium 
PB Mean (0.996 +/- 0.007) 
NOPI 320 
T = 47 Ka 
(231Pa) /(235U)

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ANL-NBS-HS-000007 REV00 89 March 2000 
(Table 6-10, DTN: LA9909MM122122.001) 
Figure 6-30. Results for 226Ra/230Th versus Distance from the Edge of the Deposit for the Fracture 
Samples 
6.5.2.1.4.2.6 Discussion and Conclusions of U-series Analyses 
Transport of some U-series nuclides at Pea Blanca has occurred over a range of time scales. 
From the U-Th age data it appears that the primary transport of U to the fractures occurred more 
than 300 ka ago. Subsequently, there has not been significant 238U or 235U redistribution. The 
231Pa/235U activity ratios for the fracture samples support this conclusion. Results for one 
anomalous sample along with U-Th ages for opal and caliche (Pickett and Murphy 1997, p. 121) 
suggest enhanced aqueous fluxes at ~50-90 ka and local U mobility. The enhanced flux had no 
effect on U (235,238), Th, or Pa distribution in the remainder of the fracture samples. The 
226Ra/230Th activity ratios indicate redistribution of radium within the last 5 ka due to secondary 
fluid events. These sorts of interactions appear to have also produced small redistributions of 
234U. Presumably, this reflects the preferential mobility of 234U resulting from selective leaching 
and direct-recoil effects. Such effects are well-documented in rock-water systems (e.g., Ivanovich 
and Harmon 1992) and are manifested by aqueous phases with elevated 234U/238U. The 
fine-grained nature of the fracture filling materials makes this mechanism especially effective at 
Pea Blanca. Therefore, while we were unable to reproduce Pickett and Murphys (1997) results 
in detail, we did confirm a recent but limited redistribution of 234U along fractures. In an analog 
sense, this stability should extend to transuranics and the rare earth elements. The high mobility of 
Ra is also noteworthy and should be considered in modeling transport of Sr and Cs. 
226Ra Plot 
Distance (m) 
0 10 20 30 
0.6 
0.7 
0.8 
0.9 
1.0 
1.1 
1.2 
1.3 
F Fracture 
C Fracture 
E Fracture 
B Fracture 
Secular Equilibrium 
(226Ra)/ (230Th)

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Our results indicate that the uranium (235, 238), thorium, and protactinium in the fracture-filling 
minerals have remained stable for more than 300 ka. This stability has apparently survived even 
recent hydrologic disturbances from surface water infiltration of the fracture due to mining 
activities, as well as the infiltration of rainwater since the fractured rock was uplifted above the 
water table (Pearcy et al. 1994, p. 714). Results for one anomalous sample and opal/caliche dating 
suggest that hydrologic disturbances occurred ~50 ka ago. In addition, the radium disequilibria 
data suggest that hydrologic disturbance(s) also occurred over the past 5 ka. Hence, it appears that 
uranium, thorium, and protactinium in secondary fracture materials are unaffected by surface 
water infiltration and perhaps saturated ground-water flow over ~100 ka time scales. This 
research provides one important indication of the probable immobility of those radionuclides in a 
high-level nuclear waste repository over its required lifetime. 
The two data sets discussed above (Figure 6-26 versus Figures 6-27 through 6-30) directly 
contrast with each other in their final interpretations. The major implication of the Pickett and 
Murphy (1997) and Wong (1998) data is that the host rhyolitic tuffs around Nopal I have not 
effectively retained the uranium mobilized from uraninite alteration. Their results suggest that the 
rocks at Yucca Mountain may not be effective barriers to actinide migration. In contrast, the more 
precise TIMS data (this work) indicate that the geochemical system at Nopal I restricts actinide 
mobility in the unsaturated environment. By analogy with our results, the tuffs at Yucca Mountain 
should have similar retentive properties to impede oxidized uranium mobility. The accumulation 
of natural analog data from Pea Blanca and similar sites would be of particular importance if it 
demonstrates the general validity (or the converse) of low actinide mobility in unsaturated 
siliceous tuffs under semi-arid climate conditions. 
6.5.2.1.5 Aqueous Transport of Uranium at Pea Blanca 
Complementary to studies of fracture-filling materials, Pickett and Murphy (1999) recently 
presented measurements of U-Th isotopic composition and concentration in various water 
samples collected near the Nopal I uranium deposit. They analyzed samples of three different 
types: perched water trapped in an old borehole about 20 m outside the deposit, seep water 
obtained from an old adit approximately 8 m below the +10 m surface, and a groundwater sample 
located in the regional carbonate aquifer 1.3 km southeast of the deposit. They also measured the 
major element chemistry of these samples including major anions, cations, pH, pO2, and 
conductivity. Samples were generally filtered (0.20 m filter) and acidified in the field, with the 
exception of the seep waters, which were filtered and acidified 11 months after collection. 
Uranium concentrations range from 170 ppt for the groundwater, to 200-900 ppt for the seep 
water, to 5 ppb for the perched water. Thorium concentrations range from 0.14 ppt (parts per 
trillion) for the groundwater, to 0.5  1.2 ppt for the seep water, to 16 - 27 ppb (parts per billion) 
for the perched water (Pickett and Murphy 1999). The U and Th concentrations generally 
correlate with concentrations of major cations and anions and total conductivity, which may 
reflect evaporation-dilution or rock dissolution effects on all of these species. Th and U 
concentrations also correlate strongly with each other, which is surprising given the expected 
differences in solution chemistry and potential solubility controls for these two elements. 
Pickett and Murphy (1999) interpret these concentrations in the context of solubility control by 
various uranium silicate minerals (haiweeite, soddyite) and thorianite. They find that the perched

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water is close to solubility for haiweeite, a calcium uranyl silicate mineral. All of the other waters 
are undersaturated with respect to uranium mineral phases. However, all of the waters are 
supersaturated with respect to thorianite, which is attributed to the presence of colloidal Th in the 
<0.2 um fraction of these samples. The overall correlation between Th and U is left unexplained, 
but seemingly points to greater control on concentrations by evaporation followed by dilution or 
rock dissolution effects. Kinetic factors present in natural systems will also complicate the 
interpretations based on thermodynamic solubility. 
Reaction path modeling suggests that uraninite dissolution under oxidizing conditions without 
continuous water replenishment will lead to a secondary U assemblage dominated by schoepite, 
allowing higher aqueous U contents (4x10-5 molal) than if controlled by uranyl silicates (Pickett 
and Murphy 1999). However, their data also show that the secondary U assemblage at Nopal I is 
dominated by uranyl silicates, which indicates geochemical processes other than those they 
modeled. 
234U/238U activity ratios are highest for the seep water (2.85-5.07), lower for the perched water 
(2.19), and still lower for the groundwater (1.39). A positive correlation between 1/U 
concentration and 234U/238U for the perched and seep waters is consistent with selective leaching 
of 234U in dilute seep waters versus greater dissolution for the perched waters. This interpretation 
is also consistent with results for the major element concentrations and Th discussed above. 
Pickett and Murphy interpret the lower 234U/238U ratio in the carbonate aquifer as resulting from 
prolonged interaction with old calcites, allowing U exchange and masking preferential 
leaching/recoil effects for 234U. 
230Th/232Th activity ratios are also highest for the seep water, which, along with the higher 
234U/238U, may reflect greater influence of selective leaching/recoil effects. 230Th/234U activity 
ratios are quite low (< 0.01) relative to typical values in the rock of 1-1.5, indicating that Th is 
significantly less mobile than U. 
6.5.2.1.6 Ongoing Work at Nopal I 
During the summer of 1999, a group of investigators from the Yucca Mountain Site 
Characterization Project (YMP) went to the Pea Blanca district to see the deposits first-hand and 
to evaluate the need for future work. Based on discussions held during this trip, we recommend 
the following areas for future work. 
6.5.2.1.6.1 Three-Dimensional Studies 
Previous work at Pea Blanca has primarily been in two dimensions with data for only exposed 
planar surfaces. Some of the fractures that are exposed on the surface actually extend through the 
deposit in the vertical plane. Little has been done regarding boreholes, and we do not know if 
there has been preferential flow/drainage downward through such fractures. For this reason, there 
is a need to extend geochemical studies to the third dimension. This extension will be 
accomplished with a borehole through the deposit. The proposed location for this borehole is 
shown in Figure 6-23 (position 00) and in Figure 6-31. Analyses of recovered core would provide

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 RE V00 92March 2000 
samples by which to evaluate the downward path of radionclide migration. Analyses would 
consist of major elements, U-series, Sr, and oxygen isotopes. 
Figure 6-31. Photo of the +10 Level, Illustrating the Location of a Proposed Drill Site to Recover Rock 
Core as Well as Groundwater. The location is within the zone of uranium mineralization at 
the feet of the person in the photo. 
6.5.2.1.6.2 Groundwater Studies at Nopal I 
Although the Pickett and Murphy (1999) study provides some useful preliminary data for waters 
at Nopal I, they were limited by availability of samples. Thus, numerous outstanding questions 
remain with respect to uranium and uranium-series transport. The extent and spatial dependence 
of uranium transport from the deposit via groundwater cannot be thoroughly evaluated without 
higher resolution sampling of any potential groundwater uranium plume in the vicinity of the 
deposit. In addition, colloidal transport of Th (and Pa or possibly U) is suggested by their 
preliminary work, but cannot be verified without concentration versus size fraction studies on 
filtered or ultrafiltered water samples. Measurements of radium isotopes serve as an analog for Cs 
or Sr transport at Yucca Mountain, but have yet to be obtained for aqueous samples. Solubility 
effects on both uranium and thorium concentrations have been considered by Pickett and Murphy, 
but generally don't appear to be of primary importance. Collection of additional samples and 
further analyses to address other possible mechanisms such as pH dependent sorption, solution 
complexation, evaporation-dilution, and rock dissolution should be useful to discern the 
important mechanisms controlling U concentration and transport. 
To address these issues, a series of water-producing wells are proposed for the site. These wells 
would be located at 00 (see Figures 6-23 and 6-32) and +50 m and 50 m (Figure 6-23) and 
500 m and +500 m. The proposed locations of the +50 and + 500 wells are marked in 
Figure 6-32. The depth to the water table is not known but is thought to be about 200 m, based on

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ANL-NBS-HS-000007 REV00 93 March 2000 
depths of nearby wells. In addition to these wells, perched water samples and samples from 
seepage tests are being collected. Sampling of the wells and seep are being conducted seasonally 
to monitor variability over time. Analyses consist of major cations and anions, U-series, Sr, and 
oxygen isotopes. 
Figure 6-32. Photo from the +10 Level, Illustrating Possible Locations of Near-Field (50 m) and 
Far-Field (500 m) Groundwater Monitoring Wells (Stars). These locations are expected to 
be down-gradient in the regional aquifer and useful for characterization of any potential 
uranium plume from the deposit 
6.5.2.1.6.3 Modeling Radionuclide Transport at Pea Blanca 
With the availability of solid and fluid samples for analyses as described above, there should be 
sufficient data to model radionclude transport at Pea Blanca using a natural analog approach. 
Such an approach is based on the parent-daughter relationships for the U and Th decay series. For 
example, in an undisturbed rock that is sufficiently old for the daughters to have grown into 
secular equilibrium, the activity of a parent radioisotope is identical to that of all its daughters. 
However, in environments where water passes through and interacts with solid phases, the 
different geochemical behavior of the nuclide leads to significant radioactive disequilibria 
between parents and daughters in the fluids and associated solids (e.g. 234/238 ratios for the 
fracture materials and water at Pea Blanca). Both thermodynamic and kinetic factors play a role 
in creating and maintaining the disequilibria. By modeling the local mass-balance of the various 
radioisotopes, with constraints placed by their different decay rates and the parent-daughter 
relationships, one can derive information on the rates of adsorption-desorption and transport of 
contaminants under a given geochemical and hydrologic environment, on time scales of days to 
1,000,000 years (Ku et al. 1992). 

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ANL-NBS-HS-000007 REV00 94 March 2000 
We have just completed such a study at INEEL that provides quantitative data on: 
 Regional flow patterns and preferential flow paths 
 Retardation factors for U, Th and Ra 
 The migration velocity of specific types of contaminants through the aquifer 
 Rock dissolution rates 
The information obtained from the natural analog study at Pea Blanca could be used to 
understand and predict the mobility (or retardation) of radioactive contaminants at Yucca 
Mountain. For example, uranium is itself of concern and is also geochemically similar to some 
transuranic elements, e.g., neptunium; Th (IV) can be used as a proxy for Pu (IV), Pa (V) for Pu 
(V), etc. The transport rate of 137Cs, 90Sr and 133Ba can be inferred from that of 226Ra, provided 
that the geochemical fractionation between Cs, Sr, Ba and Ra can be reasonably determined by 
measuring their concentrations in fluid and rock samples. The natural analog approach has 
advantages over laboratory studies and theoretical calculations in that the natural analog approach 
takes into account the combined effects of variable speciation, geologic heterogeneity and 
geologic time scales. These parameters are commonly difficult to accurately duplicate in 
laboratory and theoretical studies, but could be determined in situ at Pea Blanca using samples 
from the proposed sampling effort. 
6.5.2.1.6.4 The Timing of Recent U Mobilization at Pea Blanca 
As discussed in Section 6.5.2.1.4, much of the TIMS evidence supports the conclusion that the 
system has been closed to many U-series radionuclides for 300 ka. However, some evidence, 
consisting of U-Th dates of ~50 ka for caliche and opal (Pickett and Murphy (1997)) and a U-Pa 
age for fracture sample NOPI 320 (this study), indicates a younger mobilization event for at least 
some radionuclides. The timing, nature, and extent of such events need to be evaluated further for 
Pea Blanca in order to judge their importance at Yucca Mountain. We obtained initial samples of 
opal and calcite during our field trip to the site and will determine U-series and stable isotope data 
for these samples. 
6.5.2.2 Uranium Deposits in Northern Nevada 
Most natural analogs to radionuclide transport are located in saturated environments (e.g., Oklo, 
Gabon; Cigar Lake, Canada) or in shallow, weathered saturated/unsaturated sites (e.g., Alligator 
Rivers, Australia; Bangombe, Gabon). With regard to unsaturated zone analogs, in addition to 
Pea Blanca, the McDermitt Caldera uranium deposits and other uranium deposits in northern 
Nevada and southeastern Oregon have been mentioned as possible analogs to potential UZ 
radionuclide transport processes at Yucca Mountain (Alexander and Van Luik 1991). YMP 
representatives, including the AMR originator, visited a number of the deposits in 1995 to observe 
the geologic setting and characteristics of mineralization first-hand. As a follow-up to Project 
interest, Castor et al. (1996) compared features of sixteen of the deposits, five of which are 
located in settings with a thin vadose zone. These are the Moonlight, Bretz, and Opalite mines of 
the McDermitt caldera, Virgin Valley deposits of northwestern Nevada, and Painted Hills deposits 
near Reno, Nevada (Figure 6-33). Mines in the Lakeview District and Steens Mountain areas of 
southeastern Oregon all occur in saturated rhyolite flows, bedded tuff or mafic volcanic rock. 
Mineralization of the McDermitt caldera is discussed in Wallace and Roper (1981). For more

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ANL-NBS-HS-000007 REV00 95 March 2000 
detail on all of the deposits, the interested reader may consult the extensive reference list in Castor 
et al. (1996). 
Figure 6-33. Location Map of Uranium Districts in Northern Nevada and Southeastern Oregon (Castor 
et al. 1996, Figure 1)

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ANL-NBS-HS-000007 REV00 96 March 2000 
The age of tuffs in the McDermitt caldera and Virgin Valley is 15.7 to 16.5 Ma (Castor et al., 
1996). Depth to the water table is 38 to 50 m. At the Moonlight mine, uranium deposition has 
occurred along faults; host rocks are dacite flows and rhyolite ash flow tuffs in the footwall and 
biotite rhyolite breccias in the hanging wall. Ore deposition was associated with epithermal fluids 
and occurs mainly in the rhyolite breccias. The Moonlight mine is the only area at McDemitt with 
recorded uranium production (approximately 700 kg of U3O8 with an average grade of 
approximately 0.13% U3O8). The ore at Moonlight is exposed by an inclined adit about 80 m 
deep that is presently flooded at a depth of about 50 m. 
At the Bretz and Opalite mines, mineralization is associated with mercury (1.6% Hg) in hot 
springs and caldera ring fracture faults in silicified breccia. Uranium deposition is genetically 
related to magmatic systematics in the Virgin Valley caldera and is associated with airfall and 
minor ash flow tuffs, and lacustrine sediments including diatomite and lignite. Stratiform opal 
deposits contain uranium and uranium is also found along fractures in rhyolitic breccia. In the 
Painted Hills district near Reno, uranium mineralization is associated with late-stage 
mineralization within a caldera, and notable concentration is found at the contact between 
rhyolitic ash flow tuff and a basalt dike and as fracture filling in the tuffs. Of the sites discussed 
above, zeolites were observed only in the Virgin Valley area but have been reported at the Bretz 
and Moonlight mines. In all of the deposits mentioned, uranium is found as U(VI); only at the 
Moonlight mine is it also found as U(IV) in association with zircon. 
Some of the uranium mineralization at McDermitt caldera and the other northern Nevada deposits 
may constitute good analogs to aspects of radionuclide transport at Yucca Mountain, but this is 
questionable for several reasons. One reason is that the host volcanic rocks for these deposits are 
somewhat different (i.e., peralkaline rhyolite and trachyandesite flows, bedded tuffs, lacustrine 
sediments, and basalt dikes). Another reason is that the uranium mineralization is fine-grained 
and low in concentration in these deposits. Age of deposition is poorly constrained for most of the 
deposits. Drilling has taken place in only two of the areas, which could provide solid samples for 
analyses; hydrologic data are sparse. Previous characterization has included the geologic setting 
of uranium deposition, uranium oxidation state, primary and secondary mineral assemblages, and 
a little water chemistry (Table 6-12). 
Table 6-12. Water Chemistry Characteristics of Northern Nevada/Southeastern Oregon Uranium Districts 
(modified from Castor et al. 1996, Table 12). 
DTN: LB990930123122.001

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Furthermore, the origin of the Virgin Valley and Painted Hills deposits is uncertain. Deposition by 
ascending fluids along dike barriers is suggested since mineralization occurs almost exclusively 
along footwalls of mafic dikes. At both the Painted Hills deposits and at Virgin Valley, evidence 
suggests remobilization and redeposition of uranyl minerals to account for local enrichment. 
Source term information needed for models is lacking. 
In summary, answers to the following questions are needed for all of the northern Nevada deposits 
discussed before analogies could be made regarding potential transport at Yucca Mountain: (1) 
timing and mechanism for emplacement of primary uranium mineralization; (2) distribution of 
diagenetic minerals and their relation to uranium mineralization; (3) age, source, and trapping 
mechanism of fracture-controlled uranium mineralization; (4) physical and chemical hydrologic 
attributes of the system. In spite of their appealing proximity to Yucca Mountain for ease of study, 
the northern Nevada uranium deposits would require extensive additional characterization before 
data could be used in any sense for building confidence in flow and transport process models. 
6.5.3 Analogs to Coupled Thermal-Hydrologic-Mechanical-Chemical (THMC) Processes 
6.5.3.1In troduction 
The emplacement of heat-generating waste in a geologic repository located in an unsaturated zone 
will cause perturbations to the natural environment through heat transfer resulting from 
convection and conduction and by associated geochemical and geomechanical changes taking 
place in the repository near-field and altered rock zones. Although data collected from heater tests 
have significantly advanced the Projects understanding of thermohydrologic processes and 
coupled behavior, it will be difficult to measure repository thermohydrologic behavior 
deterministically, because of both the expense of carrying out these types of laboratory and in situ 
experiments, and the experiments being too limited for the time frame over which the processes 
take place. Natural analogs provide opportunites for testing models and building understanding in 
thermally coupled processes by assessing data from fossil hydrothermal systems, by observing 
ongoing processes in geothermal fields, and by using data from geothermal systems to test and 
build confidence in numerical modeling codes and in thermodynamic and kinetic databases. The 
following subsection discusses the three opportunities for application of natural analogs in that 
order. 
6.5.3.2 Fossil Hydrothermal and Intrusive Contacts 
The effects of shallow (<500 m) magmatic intrusions into unsaturated rocks can be quite different 
from effects associated with deeper hydrothermal systems. This section examines the thermally 
coupled hydrologic-chemical (THC) processes that are relevant to THC interactions during the 
repository post-closure period and provides natural analog cases where the effects of magmatic 
intrusion and attendant heating have been studied in both saturated and unsaturated systems. 
Processes that are relevant to THC interactions during the repository post-closure period include 
the following: zeolitization of volcanic glass, affecting transport pathways and sorption; potential 
dehydration of zeolites and vitrophyre, causing water release and affecting heat and fluid flow; 
effect of heat on sorption properties; changes in water chemistry resulting from interactions 
between engineered barriers and groundwater, which may affect seepage and flow; and fracture

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ANL-NBS-HS-000007 REV00 98 March 2000 
permeability changes caused by dissolution or precipitation of minerals, including formation of 
mineral caps. 
A good analogy for understanding future repository behavior is the fossil hydrothermal system at 
Yucca Mountain itself (Bish and Aronson 1993). Detailed mineralogical examination of Yucca 
Mountain tuffs showed that most zeolitic alteration occurred 13 to 11.6 Ma, at about the same 
time as tuff emplacement. After formation of the major zeolitic horizons, deep-seated 
hydrothermal activity persisted until about 10 Ma. This activity was limited to temperatures of 
90 to 100oC, the zeolite stability limit; at prolonged exposure to temperatures greater than 90oC, 
the sorptive zeolites clinoptilolite and mordenite are altered to analcime plus quartz and/or calcite. 
Conceptual models for mineral evolution at Yucca Mountain (Carey et al. 1997) suggest that the 
most likely mineralogical reactions caused by repository heating would include dissolution of 
volcanic glass and precipitation of clinoptilolite, clay and opal-CT; dissolution and precipitation 
of silica polymorphs (cristobalite, opal-CT, tridymite, and quartz); alteration of feldspars to clays; 
and, finally, reactions involving calcite and zeolites. Figure 6-34a illustrates paleotemperatures 
that were inferred from mineralogical data in several drillholes at Yucca Mountain. Measured 
present-day temperature profiles are shown for comparison. It can be seen from the figure that 
present-day temperatures in the drillhole G-3, which is within the repository block, compare 
closely to inferred paleotemperatures. In contrast, increasingly higher paleotemperatures are 
inferred for drillholes G-1 and G-2 which are closer to the center of the Timber Mountain caldera 
source of eruption (G-2 being the farthest north). Figure 6-34b shows mineral and glass 
abundances and clay mineralogy from GU-3/G-3 drill core that were used to infer the 
paleotemperatures. Similar mineral abundance diagrams for G-1 and G-2 drill core indicate a 
northward progression of an increasing abundance of clays and zeolites along with decreased 
abundance of glass. This is in keeping with the reactions stated above. 
Thermodynamic modeling results indicate that the stability of various zeolites is a function of 
silica activity, temperature, aqueous sodium concentration, and the mineralogy of silica 
polymorphs. Increasing temperature or sodium concentration causes the alteration of zeolites to 
other phases. Kinetic effects are, however, important in assessing the significance of 
thermodynamic and natural analog study conclusions. Kinetic data suggest that saturated 
conditions are necessary for notable progress in these reactions, as discussed by Carey et al. 
(1997). Therefore, under ambient conditions the reactions are likely to proceed more slowly in the 
Yucca Mountain unsaturated zone (excluding perched water zones) than below the water table. 
Similarly, the persistence of opal-CT below the water table indicates that silica reaction kinetics at 
Yucca Mountain are slower than laboratory studies would suggest (Carey et al. 1997). However, if 
prolonged boiling occurred in saturated tuffs, significant progress in all these reactions could 
occur. The thermal design of the repository would limit the occurence of temperatures above 
100oC to the Topopah Spring welded unit, and in any case, the current Enhanced Design 
Alternative (EDA-II) design scenario calls for sufficient drift spacing so that temperatures 
between drifts remain below boiling (CRWMS M&O 1999c). 

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Figure 6-34. Anticipated Mineral Alteration at Yucca Mountain. (a) illustrates paleotemperatures 
inferred from mineralogical data in drill holes USW G-3, G-2, and G-1 along with 
present-day temperature profiles. (b) compares mineral and glass abundances in drill core 
USW GU-3/G-3 determined by x-ray powder diffraction (CRWMS/M&O 1998a, 
pp. F6.1-75, 76). 
(a) 
(b)

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In addition to considering Yucca Mountain as a self-analog, contacts between igneous intrusions 
and host rock may provide useful information as coupled process analogs. Numerous igneous 
intrusion contact zones have been examined with the objectives of understanding chemical 
reactions and migration of elements away from the heated contact zone as well as understanding 
THC effects, both in saturated and unsaturated systems. In early studies, elemental migration 
across the 2-m-wide contact zone around the Eldora Stock in Colorado was investigated as an 
analog to elemental transfer in a crystalline repository during heating by waste canisters 
(Brookins 1986; Wollenberg and Flexser 1986). Oxygen isotope data showed a distinct contrast 
between the 60 Ma quartz monzonite stock and the Precambrian metamorphic country rock, 
which Wollenberg and Flexser (1986) interpreted to indicate a lack of hydrothermal convective 
cooling. No systematic uranium enrichment or depletion that could be related to distance from the 
contact was detected (Wollenberg and Flexser 1986), but data were insufficient to ascertain 
whether uranium mineralization occurred before or after emplacement of the stock. 
In contrast to the Eldora stock, intrusion of the Alamosa River, Colorado stock, a monzonite body 
that intruded tuffaceous and andesitic volcanic rocks about 30 Ma ago (Brookins 1984), appears 
to have established a large-scale convecting hydrothermal system (Brookins 1986). Alteration of 
the tuffs is observable to 60 m from the contact with the occurrence of calcite intergrown with the 
rock matrix, chlorite and sericite, quartz overgrowths, and epidote (Wollenberg and Flexser 1986). 
The contact itself contains a dense intergrowth of epidote, sphene, and fine hematite-filled 
fractures. Uranium occurs in sphene but is otherwise absent from the contact (Wollenberg and 
Flexser 1986). Concentration gradients of Cs, Th, and Co in the tuff increase toward the contact, 
but other trace elements show no indication of migration between the stock and the tuff 
(Wollenberg and Flexser 1986). 
The effects of shallow (<500 m) magmatic intrusions into unsaturated host rocks can be quite 
different from effects associated with deeper hydrothermal systems, which have been studied 
more extensively, and of which the two previously mentioned studies are examples. One study in 
an unsaturated environment was the contact between the Banco Bonito obsidian flow and 
underlying Battleship Rock tuff in a steep-walled canyon on the southwest rim of the Valles 
Caldera, New Mexico. This site has been the focus of a number of analog studies (Krumhansl and 
Stockman 1988; Stockman et al. 1994). The Banco Bonito flow filled a steep-walled canyon cut 
in the Battleship Rock tuff about 400 ka ago. Present hydrologic conditions are unsaturated. The 
obsidian, initially at temperatures of 850oC, heated the porous tuff in the canyon walls to 
150-350oC for decades, and, according to models, vaporized much of the pore water, and caused 
refluxing of water. Contact effects include a reddish baked zone extending tens of feet into the 
tuffs. Krumhansl and Stockman (1988) found that Cs and Rb showed little variation with distance 
from the contact whereas Th, Ta, Hf, Co and rare earth elements showed slight concentration 
trends; however, it is possible that these trends may have predated the obsidian flow. Stockman et 
al. (1994) observed no evidence of trends in trace element migration at the contact; however, 
water and Cl are depleted near the contact, whereas F is slightly enriched toward the contact. No 
evidence of hydrothermal alteration was noted, suggesting that the area was unsaturated at the 
time of contact. 
The Valles analog site presents several interesting features. First, the Battleship Rock Tuff is very 
homogeneous in major and trace element composition, such that it would be possible to detect

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distinct elemental differences caused by heating at the contact. Second, there is no hydrothermal 
overprint that could blur the effect caused by deposition of the obsidian flow. Based on a detailed 
mineralogical, chemical, and isotopic study, Stockman et al. (1994) concluded that, overall, the 
effects of heating in this unsaturated environment appeared to have been slight and were limited 
to the tuff nearest the contact. Some evidence existed for devitrification and migration of volatile 
elements in the tuff within 10 meters of the contact, but variations in major and trace element 
chemistry were small and difficult to distinguish from the natural variability of these elements in 
the rock. Apart from devitrification, the principal mineralogic change in tuff near the contact was 
the development of feldspar-silica linings on voids in the pumiceous tuff matrix; no significant 
development of zeolites was found. It was not possible to map paleoisotherms from the heating 
event, but Stockman et al. (1994) developed a model to predict the temperatures in the obsidian 
and tuff as a function of time. The model predicts the movement of a boiling front several tens of 
meters into the tuff over several hundred years and is relatively insensitive to assumed saturation. 
The influence of a shallow basaltic intrusion into pyroclastic deposits at Grants Ridge, New 
Mexico, was studied by WoldeGabriel et al. (1999). At this location, a 2.6 Ma basalt plug 
intruded into 3.3-Ma nonwelded, pumice-rich, compositionally homogeneous, rhyolitic tuff and 
volcaniclastic sediments. A 10-m-wide aureole characterized by color variation, contact welding, 
brecciation, partial melting, and stoping developed around the 150-m wide basalt plug. Despite 
the high-temperature basaltic intrusion, there was no evidence in the country rock of pervasive 
hydrothermal circulation and alteration that could have been caused by extensive fluid-driven 
convective heat transfer. WoldeGabriel et al. (1999) found that the proportion of volcanic glass, 
volatile species, Fe, and some trace element and rare earth element contents in the host rocks were 
somewhat depleted at the contact of the intrusion. In contrast, the degree of devitrification and 
potassium content were higher along the contact. The authors postulated that vapor-phase 
expulsion of elemental species could have been responsible for the minor depletion of elements 
during devitrification of the silicic glass at near-solidus temperature related to the basaltic 
intrusion. 
The Woldegabriel et al. (1999) study performed finite-difference numerical modeling to model 
the Grants Ridge intrusion as a dry, conduction-dominated system and compared its results with 
those of an analytical solution and with the heat and mass transfer code FEHM (Zyvoloski et al. 
1992, 1997). Modeling results, which agreed well with geochemical and mineralogical data, 
indicated that contact welding of the host rocks apparently occurred at temperatures > 700oC 
under a density-driven lateral load of approximately 1 Mpa, corresponding to the observed depth 
below the former ground surface of ~100m. Other physical changes in the host rock, represented 
by partial devitrification and color changes, apparently occurred at temperatures of 500 to 600oC, 
which probably persisted for up to 55 years after emplacement of the basaltic plug (WoldeGabriel 
et al. 1999). Because devitrification is generally enhanced by the presence of aqueous fluids, the 
abundance of volcanic glass within a short distance (~10 m) from the plug is consistent with the 
authors inference that the plug intruded into an unsaturated environment. Although no apparent 
hydrothermal alteration was recognized in the contact zone, this field study and others like it 
provide an upper temperature bound natural analog to evaluate the effects of heat from decay of 
radioactive waste. Results of these types of studies are also important for performance assessment 
of basaltic magma intrusions into or close to a potential repository environment. Field and

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laboratory data from the analog study can also be used to build confidence and to calibrate models 
of such processes within similar physical and chemical environments. 
In the Paiute Ridge area of the Nevada Test Site, late Miocene basaltic magma intruded a 
sequence of 22 to 11 Ma tuffs in a single magmatic pulse (Lichtner et al. 1999). The intrusions 
formed as dikes, sills, and lopoliths. The original depth of the intrusions was on the order of 150 
to 250 m (Crowe et al. 1983). A contact aureole ~3 m wide surrounds the intrusions. Matyskiela 
(1997) studied alteration surrounding one intrusion, the 50-m-wide Papoose Lake sill, in 
proposing the Paiute Ridge intrusive complex as a natural analog for THC processes at Yucca 
Mountain. Matyskielas (1997) analysis was based on a pure heat conduction model. 
Matyskielas (1997) model results indicated maximum temperatures in the tuff host rock of 550oC 
and cooling times ranging from 10 to 400 years. Matyskielas (1997) major finding was alteration 
of glass shards to cristobalite and clinoptilolite within 60 m of the intrusion. He interpreted the 
alteration as hydrothermal in origin, resulting from emplacement of the intrusion (although he 
never conclusively demonstrated that the alteration post-dated the intrusion). Most significant was 
Matyskielas (1997) observation of complete filling of pore spaces with silica at fracture-matrix 
interfaces, thus creating open conduits for infiltrating fluid flow along fractures. 
Matyskiela (1997) estimated enhanced fracture flow to be as much as five times ambient 
conditions. This is the opposite behavior to formation of a silica cap, as predicted by recent 
simulations conducted for Yucca Mountain (Hardin 1998, pp. 5.57-5.58) in which fractures would 
become filled with quartz or chalcedony, thus inhibiting further flow. Here a contradiction exists 
between modeling results and limited field observations that needs to be resolved. An issue is the 
extent to which a fracture can be filled by the silica contained in matrix pore water. Figure 6-35 
shows that for a given matrix porosity, the degree of sealing of the fracture depends on the 
fracture volume fraction and the particular silica polymorph that precipitates (Lichtner et al. 
1999). This analysis is predicated upon the assumption that as pore fluid in the matrix is brought 
into equilibrium with respect to a particular silica polymorph (e.g., amorphous silica) at boiling 
conditions, the matrix fluid boils and escapes into the surrounding fracture network. As the fluid 
vaporizes, its released silica content precipitates in fractures. Lichtner et al.s (1999) two-phase 
numerical simulation results suggest that at distances of tens of meters from the larger of the 
Paiute Ridge intrusions that they studied (width > 39 m), prolonged boiling conditions were 
established for times on the order of several thousands of years. The analysis shown in 
Figure 6-35 represents a limiting case and is dependent on all pore water flashing to steam in the 
fracture, as assumed in Section 5, Assumption #11. Amorphous silica, with its higher solubility, 
gives the largest fracture filling, followed by chacedony and quartz. For complete sealing of the 
fracture, a very small fracture volume fraction is necessary. Moderate filling could represent 
fracture coatings that armor the fracture. 

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Figure 6-35. Volume of Silica Polymorphs Precipitated in Fracture as a Function of Volume Fraction for 
a Matrix Porosity fm = 0.1 ( from Lichtner et al. 1999, Figure 10). A volume fraction of one 
represents complete filling of the fracture, assuming that the fracture was initially open. 
THC processes can be better constrained through analysis of selected intrusive complexes hosted 
in unsaturated tuffaceous rock. The ideal intrusion to serve as a natural analog to THC processes 
anticipated at a Yucca Mountain repository should have been emplaced above the water table, 
should be of sufficient size to produce enough heat to sustain boiling conditions for times on the 
order of several thousand years (~30 m width), and should occur in host rock of similar 
composition and characteristics to the Topopah Spring Tuff. The Paiute Ridge intrusive complex 
satisfies the first two criteria, but the tuff host rock into which it has intruded is a nonwelded vitric 
tuff. Nevertheless, this does not exclude it as a meaningful analog. Field observations at the Paiute 
Ridge complex could help to determine key mineral reactions and possible reaction rates. 
In summary, in both the Banco Bonito study and the Grants Ridge basalt intrusion study, the 
effects of high-temperature intrusions into unsaturated environments appeared to have been 
slight, to have been limited to within 10 m or so of the contact, and to show no evidence of fluid 
driven convective heat transfer or pervasive hydrothermal alteration of the country rock. These 
field studies, along with the Paiute Ridge field studies, provide data for assessment of magmatic 
intrusions into or near a potential repository. But just as importantly, they provide a limiting case 
natural analog for evaluating effects of heat from decay of radioactive waste in an unsaturated 
environment. 
6.5.3.3 Geothermal Systems 
Many processes that are expected to take place under repository conditions are the same as those 
that occur in geothermal fields. These include evaporation, boiling, condensation, single- and 
two-phase fluid flow, mineral alteration and reaction, mineral precipitation and dissolution, and 
consequent potential changes in fracture-matrix interaction. Behavior of coupled processes 
related to geothermal systems has been observed, measured, and simulated for more than two 
decades in the geothermal industry. Data and analyses from geothermal analogs yield important 
Boiling Estimate of Silica Precipitation in Fractures

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information about expected thermohydrologic conditions at Yucca Mountain and about 
perturbations caused by thermally induced geochemical and mechanical changes in the rock mass. 
Geothermal analogs are one of the major ways of building confidence in understanding the 
thermohydrologic behavior of the repository system as it is coupled to chemical processes over 
long time periods. Data from geothermal fields can be used to test coupled process modeling 
codes used by the YMP in order to match observations (e.g., chemical reactions, occurrence of 
heat pipes) in geothermal fields with those predicted by the code. 
Many active geothermal fields throughout the world could serve as potential analog sites to some 
hydrothermal conditions expected to occur at Yucca Mountain. An appropriate candidate site 
would include features such as temperatures ranging from 25 to 300oC, a broad range of 
phenomena and features available for study, a range of water chemistries that would bound those 
expected to occur at Yucca Mountain, a range of hydrologic properties (e.g., porosity, 
permeability, fracture characteristics) similar to Yucca Mountain, water-saturated and unsaturated 
environments, a suite of hydrothermal alteration minerals similar to those expected to form at 
Yucca Mountain (e.g., zeolites and clays), evidence of fracture-matrix interactions, an active 
monitoring system, and access to extensive data sets from the recorded history of the field. 
Because many of the same thermohydrologic processes operating in geothermal systems are 
applicable to behavior of a nuclear waste repository, the same numerical tools may be utilized to 
study thermohydrologic evolution in both environments. Geothermal reservoir simulators have 
been used to model laboratory experiments, to study fundamental aspects of geothermal reservoir 
dynamics, and to perform simulation studies, such as parameter matching and field history studies 
in their various natural, exploited, and predicted states for dozens of specific geothermal fields. 
For all of these applications, it is essential that users have a high level of confidence in the ability 
of their numerical tools to simulate processes and predict thermohydrologic conditions over 
extended time periods. 
The versatility of geothermal reservoir simulators has made possible their application to a wide 
range of fluid and heat flow problems. Some of the main areas in which numerical simulation 
studies have produced significant advances in understanding geothermal systems include: 
(1) pressure decline in the depletion of boiling reservoirs, (2) evaluation of boiling and 
condensation zones, (3) reservoir exploitation strategies, (4) vapor-dominated and 
liquid-dominated heat pipes, (5) transition from liquid-dominated to vapor-dominated systems, 
(6) natural evolution of hydrothermal convection systems, (7) fluid and heat transfer in fractured 
porous media, (8) nonisothermal and two-phase well testing, (9) effects of reinjection and natural 
recharge, and (10) noncondensable gas effects. 
Numerical simulators in geothermal studies are used to determine the characteristic parameters of 
reservoirs, especially the reserves of heat and fluid, and to simulate the performance of reservoirs 
upon production and injection. To produce an adequate model, numerical codes must be able to 
handle processes of heat transfer, two-phase flow under nonisothermal conditions in one, two, and 
three dimensions with varying degrees of non-linearity, coupling of fluid and heat flows, and 
complex boundary conditions. Solution of two-phase fluid flow problems with heat transport in a 
fractured porous medium is a challenging task that adds complexity when modeled in three 
dimensions, as is being done for the Yucca Mountain performance assessment. Modeling of

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geothermal systems has provided major advances toward this goal, which adds confidence to 
numerical models of Yucca Mountain. 
Table 6-13 provides a comparison between issues important to assessing coupled processes that 
may occur at Yucca Mountain and processes taking place in geothermal reservoir systems. Some 
issues that are important for assessing Yucca Mountain, such as water saturation near the heater 
and localized seepage, have been omitted from the list because they are not of concern in 
geothermal reservoir engineering. The table shows geothermal fields that could be used as 
potential analogs to study THC processes. Corresponding to each issue, geothermal sites are listed 
that may, upon further evaluation, provide added confidence in modeling thermally coupled 
processes at Yucca Mountain using approaches suggested in column 4 of the table. 
Conflicting conclusions regarding the effect of mineral precipitation on fracture permeability, 
reported in Section 6.5.3.2 and identified as having uncertainty by PA (see Section 7.2), point 
toward THC processes (three of the four last issues in column 1 of table 6-13) as having high 
priority for additional study in active geothermal systems. Logically fields with high similarity 
factors to Yucca Mountain would be the first to investigate. These would include fields such as 
Larderello, Long Valley, Yellowstone, and several of the New Zealand fields and Reykjanes.

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Table 6-13. Application of Geothermal Field Information as Analogs to Coupled Processes Anticipated at a 
Potential Yucca Mountain Repository 
Yucca Mountain Issue 
Geothermal 
Analog 
Potential Sites Possible Approach 
Multiphase Flow (liquid, 
vapor, gas) 
Multiphase Flow (liquid, 
vapor, gas) 
All Numerical Modeling, Conduct 
and Review Geothermal 
Post Audits 
Hydrologic PropertiesH ydrologic Properties 
Kamojang (Indonesia), Tianjin 
(China), Wairakei (New 
Zealand), Oguni (Japan), Sumikawa 
(Japan) 
Numerical Modeling 
Preferential Flow Preferential Flow Wairakei (New Zealand), The 
Geysers (CA), Dixie Valley (NV), 
East Mesa (CA), Cerro Prieto 
(Mexico) 
Numerical Stochastic Modeling, 
Evaluate Geothermal 
Tracer Study Results 
Fracture Network Permeability 
Fracture Network 
Permeability 
All Modeled Fractured Sites, e.g. 
Cerro Prieto (Mexico), Krafla 
(Iceland), Matsukawa (Japan), 
Sumikawa (Japan), Olkaria 
(Kenya), Krafla (Iceland), Wairakei 
(New Zealand), Geysers 
(CA), Kamojang (Indonesia), 
Larderello (Italy) 
Reservoir Model Calibrations 
Used 
Fracture-Matrix Interaction Fracture-Matrix 
Interaction 
Yellowstone (WY), Long Valley 
(CA), Olkaria (Kenya), Fenton 
Hill (NM), Dixie Valley (NV) 
Field and Laboratory Experiments, 
Evaluate Geothermal 
Tracer Study Results 
Heat Pipes, Boiling and Condensation 
Heat Pipes, Boiling 
and Condensation 
The Geysers (CA), Kamojang 
(Indonesia), Matsukawa 
(Japan), Larderello (Italy) 
Numerical Modeling to 
Extend Measurements 
Mineral Precipitation and Dissolution 
Mineral Precipitation 
and Dissolution 
Larderello (Italy), Dixie Valley 
(NV), Wairakei (New Zealand), 
Broadlands (New Zealand), 
Long Valley (CA), Yellowstone 
(WY) 
Laboratory Experiments, 
Analog Site Investigation, 
Numerical Modeling 
Self-Sealing CaprocksTh e Geysers (CA), Kamojang 
(Indonesia), Matsukawa 
(Japan), Larderello (Italy), Cerro 
Prieto (Mexico), Reykjanes (Iceland) 
Core Sample Evaluation, 
Water Chemistry Evaluation, 
Numerical Modeling 
Mineral Alteration Mineral Alteration Wairakei (New Zealand), Broadlands 
(New Zealand), Dixie Valley 
(NV), Yellowstone (WY) 
Core Sample Evaluation, 
Numerical Modeling 
Thermo-Hydro-Mechanical 
Effects 
Subsidence, Flow 
Changes 
Wairakei (New Zealand), Bulalo 
(Philippines), Krafla (Iceland) 
Numerical Modeling 
Similarity Factor for comparison to Yucca Mountain: a 
- similar water chemistry, b - similary geology, c - similar 
alteration mineralogy. 
Larderello (Italy) - b, possibly c: Yellowstone (WY) - a,b,c; Fenton 
Hill (NM) - b; Dixie Valley (NV) - c; Wairakei (New Zealand) - 
a,b.c; Broadlands (New Zealand) - a,b,c; Long Valley (CA) - a,b, 
possibly c.

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The capabilities and limitations of geochemical modeling codes such as the solubility/speciation 
and reaction path code EQ3/6 (Wolery and Daveler 1992) and thermodynamic databases have 
been tested by analyzing natural hydrothermal systems that have some mineralogical and 
environmental similarities to Yucca Mountain. The Yellowstone caldera closely duplicates 
characteristics of the volcanic sequence at Yucca Mountain and temperatures anticipated at the 
candidate repository horizon. The Yellowstone volcanic sequence is dominated by Quaternary 
silicic welded ash flow tuffs and rhyolite flows. Geothermal activity is reflected in hundreds of 
hot springs and geysers which emit waters that have circulated through the volcanic rocks and 
have formed a variety of hydrothermal mineral assemblages. Using data from 13 USGS drill cores 
as a basis for deriving paragenetic sequences of mineral deposition in the Yellowstone geothermal 
systems, Meijer (1987) conducted preliminary thermodynamic simulations using an early version 
of EQ3/6. His evaluation suggested that the most significant effects of the thermal pulse on the 
chemical environment at the repository horizon would be the transport and redeposition of silica 
along hydrologic and thermal gradients and the precipitation of clays in the groundmass of the 
devitrified repository host rock. Secondary effects could include the deposition of clays and 
zeolites in fractures and cavities adjacent to the repository and in the underlying vitrophyre. These 
horizons should remain stable unless acidic groundwater conditions are generated in association 
with the repository. Results of Carey et al.s (1997) model of mineral evolution at Yucca Mountain 
compared favorably with Meijers (1987) simulations. 
Bruton et al. (1995) catalogued a survey of literature and data for many geothermal fields as a 
means of selecting a field analog site for thermohydrologic-chemical studies at Yucca Mountain. 
The sites included in their survey numbered among them many of the better-known geothermal 
fields: The Geysers, California; Krafla and other geothermal areas in Iceland; Cerro Prieto, 
Mexico; Valles Caldera, New Mexico; Larderello, Italy; Long Valley Caldera, California; 
Yellowstone, Wyoming; and the Wairakei and Ohaaki-Broadlands fields of New Zealand. Some 
of these fields were considered unsuitable because they occurred in rock types dissimilar to Yucca 
Mountain, a few lacked sufficient data or had access problems, and others were entirely liquid- or 
vapor-dominated fields. The geothermal system at Wairakei was selected by the Yucca Mountain 
Project as the site most amenable to study of THC processes because it possessed the greatest 
number of features similar to Yucca Mountain (Bruton et al. 1995, p. 8), because of logistic 
practicalities, and the potential for collaborative research. 
EQ3/6 was used to simulate mineral-fluid relations in the Wairakei geothermal field and other 
New Zealand geothermal fields (Glassley and Christensen 1992; Bruton et al. 1993). 
Comparisons between observed mineral assemblages and model simulations of equilibria were 
used to evaluate the thermodynamic database for various environmental conditions encompassing 
the possible range of temperatures and water conditions anticipated in a Yucca Mountain 
repository system. The results of these modeling studies are generally consistent with observed 
vein and matrix mineral equilibria at Wairakei for fluids at temperatures greater than 240oC. Both 
field data and model results indicate that stable mineral assemblages can be significantly 
impacted by small differences in fluid chemistry, temperature, or pressure. Comparison of 
laboratory data with field data from natural hydrothermal waters at Wairakei for amorphous silica 
precipitation has shown that significant discrepancies exist between results obtained with 
different test conditions (Carroll et al. 1995). Rates measured in the field were 400 times faster 
than those obtained in laboratory measurements. Silica precipitation under repository conditions

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at Yucca Mountain could exhibit rate behavior somewhere in the range between the laboratory 
and field experiments. 
The results of these studies emphasize two points necessary for use of natural systems in model 
validation. First, the natural systems must be thoroughly understood and quantitatively 
characterized, if rigorous testing of simulations is to be completed. Second, simulations must be 
capable of providing predictive results that can be tested in an active field setting. The chemical 
and hydrological features associated with actively evolving systems must be amenable to 
measurement and study, if kinetically controlled systems are to be rigorously simulated. 

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7. CONCLUSIONS AND ONGOING STUDIES 
7.1CONCLUSIONS 
Carefully selected natural analogs are important tools for understanding flow and transport 
processes anticipated to occur at a potential nuclear waste repository. The instrumental use of 
natural analogs in building confidence in conceptual and numerical models has been 
demonstrated by a literature study and analyses related to the key unsaturated zone flow and 
transport processes relevant at Yucca Mountain. The analyses were the Box Canyon study of flow 
in fractured media (Section 6.5.1.1) and the Pea Blanca study of radionuclide sequestration in 
fractured rhyolitic tuff (Section 6.5.2.1). Specific conclusions drawn from the literature study and 
analyses follow. 
Using numerical simulation of the extensive data set from tracer infiltration tests, the Box Canyon 
study demonstrated that conceptual models and large-scale, volume-averaged numerical 
modeling approaches used for the UZ flow and transport model at Yucca Mountain can be applied 
with confidence. A consistent set of parameters was obtained to calibrate the site-wide model to 
both pneumatic and infiltration tests using the dual-permeability approach. 
From the Pea Blanca U-Th age data, it appears that the primary transport of uranium (U) to the 
fractures occurred more than 300 ka ago. The 231Pa/235U activity ratios for the fracture samples 
support this conclusion. The 226Ra/230Th activity ratios indicate redistribution of radium (Ra) 
within the last 5 ka as a result of secondary fluid events caused by hydrologic disturbance(s). 
Hence, it appears that uranium (235, 238), thorium, and protactinium (Pa) in secondary fracture 
materials are unaffected by surface water infiltration and perhaps saturated groundwater flow over 
~100 ka time scales. Therefore, the data demonstrate a high degree of stability for uranium 
(235,238), thorium, and protactinium in fracture-filling materials. In an analog sense, this stability 
should extend to transuranics and the rare earth elements. The high mobility of Ra is also 
noteworthy and should be considered in modeling transport of strontium (Sr) and cesium (Cs). By 
analogy with our results, the tuffs at Yucca Mountain should have similar retentive properties to 
impede oxidized uranium mobility. 
The effects of shallow (<500 m) magmatic intrusions into unsaturated rocks can be quite different 
from effects associated with deeper hydrothermal systems. In the Banco Bonito study, the effects 
of heating in this unsaturated environment appeared to have been slight and to have been limited 
to within 10 m of the contact, although the boiling front predicted by modeling advanced several 
tens of meters into the tuff over several hundred years. Similarly, in the Grants Ridge basalt 
intrusion study, despite the high temperature intrusion, there was no evidence of fluid-driven 
convective heat transfer or pervasive hydrothermal alteration of the country rock. These field 
studies, along with the Paiute Ridge field studies, provide data for assessment of magmatic 
intrusions into or near a potential repository. But just as importantly, they provide a limiting case 
natural analog for evaluating effects of heat from decay of radioactive waste in an unsaturated 
environment. 
Our literature study noted the utility of applying thermodynamic/kinetic modeling codes to 
hydrothermal data in carefully selected systems for building confidence in mineral reactions and 
rates. Analyses utilizing codes capable of handling reactive transport associated with thermally

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coupled processes, such as those used in geothermal studies, are needed to represent the potential 
changes in hydrologic properties caused by mineral precipitation or dissolution. The changes in 
hydrologic properties and the extent of reaction of host rock to heat, as noted above, will be quite 
different in dry and saturated systems. 
The modeling studies that used data from hydrothermal waters and minerals at New Zealand 
emphasize two points necessary for use of natural systems in model validation. First, the natural 
systems must be thoroughly understood and quantitatively characterized if rigorous testing of 
simulations is to be completed. Second, simulations must be capable of providing predictive 
results that can be tested in an active field setting. Codes utilized in geothermal reservoir 
simulations provide the necessary tools for such a task while data sets from geothermal fields 
such as those listed in Table 6-13 provide the field data for exercising the codes. 
7.2 BASIS FOR ONGOING ANALOG STUDIES 
7.2.1Con fidence-Building in Total Sys tem Pe rformance A ssessment (TS PA) and the 
License Application Through Natural Analogs 
The fourth of five elements of the post-closure safety case for the Site Recommendation-License 
Application (DOE 1999), calls for an assessment of insights gained from the study of natural 
analogs. Relevant information about the possible system performance of the site can be gleaned 
from analysis of natural processes that share characteristics with the repository system...These 
data may provide a degree of independent validation of the reasonableness of selected aspects of 
the assessments of repository performance (DOE 1999, p. 15). As the safety case evolves, it 
seems likely that natural analog information will be used in the confirmatory sense for the 
reasonable case, rather than supporting the safety arguments. However, the principal factors 
upon which the safety case is based, as well as the other factors that will be bounded, may be 
strengthened from confidence-building through natural analogs. 
The TSPA Viability Assessment (VA) made no specific recommendations for use of natural 
analogs, but did discuss processes that were sensitive in TSPA calculations and that need to be 
understood with greater certainty. The TSPA-VA indicated that for peak dose rates, the fraction of 
waste packages contacted by seepage water was the most important parameter in each of the three 
simulation periods (10,000, 100,000, and 1,000,000 year) (CRWMS M&O 1998d, p. 11-58). Its 
effect becomes more dominant over time because an increase in the number of waste packages 
contacted by water leads to an increase in radionuclide releases from the repository. 
The seepage model for TSPA assumed steady-state conditions and neglected the effect of the rock 
matrix. Drift collapse and thermal alteration of hydrologic properties were not considered. 
TSPA-VA stated that the possibility of episodic flow at the repository and its effect on seepage 
needs further study as well as the effect of discrete fracture flow (CRWMS M&O 1998d, p. 
11-58). Natural analogs may be used to investigate the effects of drift collapse and thermal 
alteration of hydrologic properties on drift seepage. 
The TSPA-VA model of UZ transport did not account for a number of processes, including 
alteration of the UZ caused by thermal alteration of minerals, chemical interactions of repository 
materials, mineral dissolution, and precipitation. Thermal-chemical alteration could cause

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reduced matrix sorption and fracture-matrix interaction, thereby causing increased release rates 
from the UZ. Another process not accounted for was the ability of host rock to filter out colloids. 
A third process not accounted for was fracture sorption. However, the assumptions of no colloid 
filtration and no radionuclide sorption onto fracture surfaces are conservative for transport in the 
UZ. Although sensitivity studies conducted to date have found that transport is not highly 
sensitive to fracture sorption, this result requires further investigation to better define the 
appropriate range of parameters for fracture sorption. Radionuclide transport in the UZ is 
sensitive to changes in matrix diffusion, which suggests that further effort is needed to bound the 
magnitude of matrix diffusion (CRWMS M&O 1998c, p. 7-92). 
According to TSPA-VA, process-level modeling of chemical alteration to fracture properties 
should be considered in the license application time frame. Formation of a mineral cap 
surrounding the emplacement drift has been suggested in modeling studies (Hardin 1998 p. 5.57 
and 5.58) as a result of phase-change processes during thermal loading. Matyskielas (1997) 
natural analog study also suggested that boiling of fracture fluids may cause deposition of 
minerals that alter the flow through the fracture system, although Lichtners (1999) analysis 
challenges this conclusion. This issue should be investigated further through geothermal and 
fossil hydrothermal analogs because the fracture-matrix interaction parameter is potentially a key 
factor in describing the processes altered by chemistry and subsequently the manner in which 
fractures and matrix rock communicate with each other. The TSPA (CRWMS M&O 1998b, 
p. 3-164) noted that it is essential that the flow processes be accurately represented so that an 
assessment can be made as to whether or not the development of mineral deposits is physically 
realistic. A major question to be addressed is whether water will remain in the system long 
enough to allow for precipitation in fractures or whether it will flow through the fracture network 
during the condensate drainage period such that precipitation in fractures is minimal. Natural 
analogs of carefully selected systems may help to place bounds and add realism to the 
conceptualization of coupled thermohydrologic-chemical effects. 
Thermohydrologic-mechanical (THM) processes were not considered in the TSPA. Although not 
as long-lasting as the chemically driven processes, THM processes may alter fracture properties 
and hence flow fields during thermal compression and expansion in the heating period. Although 
most of the mechanical effects tend to be reversible, and at most would permanently change the 
natural permeability by an order of magnitude (CRWMS M&O 1998b, p. 3-164), the mechanical 
influence on the fracture network may require further analysis with respect to large-scale 
gas-phase flow effects while the repository is at its hottest. An anthropogenic analog, such as an 
underground facility with decades of monitoring data, may be useful for building confidence in 
THM issues. 
7.2.2 Ongoing Investigations 
In FY99, the Yucca Mountain Project began to address areas that could benefit from improved 
confidence through natural analog studies. A synthesis was prepared of knowledge gained from 
natural analog studies by the international community and anthropogenic analog sites in the 
United States regarding not only flow and transport processes in the UZ, but all relevant natural 
and engineered barrier system processes. The synthesis will be published in the Yucca Mountain 
Site Description for the Site Recommendation. This will help to identify areas of existing analog 
information that can be used to build confidence in understanding long-term behavior of a waste

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repository and areas where no appropriate analogs can be identified. It will help to focus the 
future direction of the YMP natural analog program with regard to study of particular sites. 
The existing uncertainties and limitations of UZ flow and transport models that can be addressed 
through natural analogs have been discussed in Section 7.2.1. The purpose of conducting the 
specific additional analog studies is to ascertain that, for areas of uncertainty, the bounds placed 
on flow, transport, and thermally coupled processes are reasonable and the approaches taken in 
modeling them capture the processes correctly. As a result of our natural analog study of UZ flow 
and transport processes for this AMR, the following ongoing investigations are being conducted. 
Rainier Mesa data will be revisited to evaluate data gaps and determine where additional limited 
data collection may be helpful. These data will be used in drift seepage models to compare to 
seepage under long-term average climate conditions. The data will be used to evaluate episodic 
pulses, such as those that affect the PTn, flow patterns and percolation fluxes from geochemical 
signatures, and sorption in vitric and zeolitic units. 
For confidence in radionuclide transport, it is necessary to use information from both natural and 
anthropogenic systems. Natural analog systems provide information where long-term behavior is 
well understood but where the suite of radionuclides may differ from Yucca Mountain and where 
initial conditions are poorly understood. Anthropogenic systems are studied for a different reason; 
i.e., numerical models of Yucca Mountain flow and transport must be able to match predictions 
for anthropogenic sites over the short-term or they will not be able to sustain confidence in their 
predictions for Yucca Mountain over the long term. Here, data from Hanford, INEEL, NTS, and 
perhaps other sites with known leakage along fast pathways are being utilized, but with caution. 
The matter of plugging data from these sites into Yucca Mountain models is neither trivial nor 
straightforward. 
Because previous work at Pea Blanca was primarily associated with two-dimensional fracture 
exposures on planar surfaces, we do not know whether there has been preferential flow/drainage 
downward through fractures. Therefore, geochemical studies are being extended to the third 
dimension. This will be accomplished with a cored borehole in FY00. Analyses of recovered core 
will provide samples by which to evaluate the downward path of radionuclide migration. Second, 
the extent and spatial dependence of uranium transport from the deposit through groundwater 
cannot be thoroughly evaluated without higher resolution sampling of any potential groundwater 
uranium plume in the vicinity of the deposit. To address this issue and others related to 
mechanisms controlling U concentration and transport, we will drill a series of water-producing 
wells, supplemented by collecting samples from perched water and a seepage test. 
With the availability of solid and fluid samples, it is expected that there will be sufficient data to 
model radionuclide transport at Pea Blanca using a natural analog approach based on 
parent-daughter relationships for the U and Th decay series. The natural analog approach takes 
into account the combined effects of variable speciation, geologic heterogeneity, and geologic 
time scales. These parameters are commonly difficult to accurately duplicate in laboratory and 
theoretical studies, but will be determined in situ at Pea Blanca using samples from the proposed 
sampling effort. Finally, are using U-series and stable isotope data for samples of opal and calcite 
to determine the timing, nature, and extent of mobilization events in the 50-ka range and to judge 
their importance for predictive models for Yucca Mountain.

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For understanding potential thermohydrologic processes at Yucca Mountain, the type of data that 
can be collected in a practical sense (e.g., field test point measurements) limits the ability to 
confirm models directly. For this reason, knowledge of long-term geothermal system behavior 
provides an appealing potential analog to understanding processes that may occur at a Yucca 
Mountain repository over millenia. We are investigating systems identified on Table 6-13 as 
having similar thermohydrologic-chemical characteristics to those predicted at Yucca Mountain 
for building confidence in numerical models of thermally coupled processes. We are building on 
previous THC thermodynamic and kinetic modeling studies described in this report to include the 
testing of reactive transport codes and models (e.g., TOUGHREACT, FEHM) using natural 
analog data. TOUGHREACT (Xu and Pruess 1998) has been applied to ESF heater test data and 
FEHM has been applied to study reactions at the Grants Ridge and Paiute Ridge igneous contact 
sites, but we know of no case in which a reactive transport code has been tested with geothermal 
analog data to consider the back-coupling effects of mineral reactions on hydrologic properties of 
a system. This type of coupling should be represented correctly in numerical models to match 
long-term, large-scale geothermal data before it can be modeled with confidence at Yucca 
Mountain. 
Field studies provide a testing ground for THC codes and for building confidence in 
thermodynamic and kinetic models used to calculate mineral reactions. Observations of 
fracture-matrix margins may provide a means for testing and validating porosity-permeability and 
fracture-matrix interaction models employed in THC codes. For this reason, we are improving 
confidence in THC processes and models through analysis of selected intrusions hosted in 
unsaturated tuffaceous rock, such as portions of the Paiute Ridge intrusive complex. A detailed 
petrologic study of devitrified and vitric host rocks as a function of distance from the intrusive 
contact is being conducted to determine key mineral reactions and hydrologic effects. Field 
observations at the Paiute Ridge complex will help to estimate kinetically and thermodynamically 
possible mineral reaction rates and to determine whether mineral reactions act to increase or 
decrease matrix or fracture permeability. 

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8. INPUTS AND REFERENCES 
8.1 DOCUMENTS CITED 
Ahlers, C.F.; Finsterle, S.; and Bodvarsson, G.S. 1999. Characterization and Prediction of 
Subsurface Pneumatic Response at Yucca Mountain, Nevada. Journal of Contaminant 
Hydrology 38 (1-3), 4768. Amsterdam, The Netherlands: Elsevier Science. TIC: 244160. 
Alba, L.A. and Chavez, R. 1974. K-Ar Ages of Volcanic Rocks from the Sierra Pena Blanca, 
Chihuahua, Mexico. Isochron/West, 10, 2123. Socorro, New Mexico: Bureau of Mines and 
Mineral Resources. TIC: 246110. 
Alexander, D.H. and Van Luik, A.E. 1991. Natural Analogue Studies Useful in Validating 
Regulatory Compliance Analyses. Validation of Geosphere Flow and Transport Models 
(GEOVAL), Proceedings of a NEA/SKI Symposium, Stockholm, Sweden, May 1417, 1990, 
589597. Paris, France: Organization for Economic Cooperation and Development. 
TIC: 246109. 
Allard, T. and Muller, J.P. 1998. Kaolinite as an In Situ Dosimeter for Past Radionuclide 
Migration at the Earth's Surface. Applied Geochemistry, 13 (6), 751765. Oxford, UK: Elsevier 
Science. TIC: 246131. 
Baehr, A.L. and Hult, M.F. 1991. Evaluation of Unsaturated Zone Air Permeability through 
Pneumatic Tests. Water Resources Research 27 (10), 26052617. Washington, D.C.: American 
Geophysical Union. TIC: 245788. 
Bandurraga, T.M. and Bodvarsson, G.S. 1999. Calibrating Hydrogeologic Parameters for the 
3-D Site-Scale Unsaturated Zone Model of Yucca Mountain, Nevada. Journal Of Contaminant 
Hydrology 38 (13), 25-46. Amsterdam, The Netherlands: Elsevier Science Publishers. TIC: 
244160. 
Benito, P.H.; Cook, P.; Faybishenko, B.; Freifeld, B.; and Doughty, C. 1998. Box Canyon 
Pneumatic Connectivity Study: Preliminary Data Analysis. LBNL-38060. Berkeley, California: 
Lawrence Berkeley National Laboratory. TIC: on order. 
Bish, D.L. and Aronson, J.L. 1993. Paleogeothermal and Paleohydrologic Conditions in Silicic 
Tuff from Yucca Mountain, Nevada. Clays and Clay Minerals, 41 (2), 148161. Long Island 
City, New York: Pergamon Press. TIC: 224613. 
Brookins, D.G. 1984. Natural Analogs. Geochemical Aspects of Radioactive Waste Disposal, 
197-231. New York, New York: Springer-Verlag. TIC: 206675. 
Brookins, D.G.1986. Natural Analogues for Radwaste Disposal: Elemental Migration in 
Igneous Contact Zones. Chemical Geology, 55, 337344. Amsterdam, The Netherlands: 
Elsevier Science Publishers. TIC: 246170. 
Bruton, C.J.; Glassley, W.E.; and Bourcier, W.L. 1993. Testing Geochemical Modeling Codes 
using New Zealand Hydrothermal Systems. Proceedings of the Topical Meeting on Site 

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 116 March 2000 
Characterization and Model Validation: FOCUS 93, September 26-29, 1993, Las Vegas, 
Nevada, 240245. La Grange Park, Illinois: American Nuclear Society. TIC: 102245. 
Bruton, C.J.; Glassley, W.E.; and Meike, A. 1995. Geothermal Areas as Analogs to Chemical 
Processes in the Near-Field and Altered Zone of the Potential Yucca Mountain, Nevada 
Repository. UCRL-ID-119842. Livermore, California: Lawrence Livermore National 
Laboratory. ACC: MOL.19960408.0126. 
Carey, J.W.; Chipera, S.J.; Vaniman, D.T.; and Bish, D.L. 1997. Three-Dimensional Mineralogic 
Model of Yucca Mountain, Nevada, Rev. 1.1, Draft R0. Milestone Report SP32B5M4. Los 
Alamos, New Mexico: Los Alamos National Laboratory. ACC: MOL.19980520.0170. 
Carroll, S.; Mroczek, E.; Bourcier, B.; Alai, M.; and Ebert, M. 1995. Comparison of Field and 
Laboratory Precipitation Rates of Amorphous Silica from Geothermal Waters at 100oC. 
Milestone Report MOL207. Livermore, California: Lawrence Livermore National Laboratory. 
ACC: MOL.19960415.0465. 
Castor, S.B.; Henry, C.D.; and Shevenell, L.A. 1996. Volcanic Rock-Hosted Uranium Deposits in 
Northwestern Nevada and Southeastern OregonPossible Sites for Studies of Natural Analogues 
for the Potential High-Level Nuclear Waste Repository at Yucca Mountain, Nevada. Report from 
Mackey School of Mines. Reno, Nevada: University of Nevada. ACC: MOL.19960927.0026. 
Crowe, B.; Self, S.; Vaniman, D.; Amos, R.; and Perry, F. 1983. Aspects of Potential Magmatic 
Disruption of a High-Level Radioactive Waste Repository in Southern Nevada. Journal of 
Geology, 91, 259276. Chicago, Illinois: University of Chicago Press. TIC: 216959. 
CRWMS M&O (Civilian Radioactive Waste Management System Management and Operating 
Contractor) 1998a. Yucca Mountain Site Description. Book 3-Section 6, 7. 
B00000000-01717-5700-00019-00. Las Vegas, Nevada: CRWMS M&O. ACC: 
MOL.19981021.0043. 
CRWMS M&O 1998b. Thermal Hydrology. Chapter 3 of Total System Performance 
Assessment-Viability Assessment (TSPA-VA) Analyses Technical Basis Document. 
B00000000-01717-4301-00003-00. Washington D.C.: DOE OCRWM. ACC: 
MOL.19980724.0392. 
CRWMS M&O 1998c. Unsaturated Zone Radionuclide Transport. Chapter 7 of Total System 
Performance Assessment-Viability Assessment (TSPA-VA) Analyses Technical Basis Document. 
B00000000-01717-4301-00003-00. Washington D.C.: DOE OCRWM. ACC: 
MOL.19980724.0396. 
CRWMS M&O 1998d. Summary and Conclusions. Chapter 11 of Total System Performance 
Assessment-Viability Assessment (TSPA-VA) Analyses Technical Basis Document. 
B00000000-01717-4301-00003-00. Washington D.C.: DOE OCRWM. ACC: 
MOL.19980724.0400.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 117 March 2000 
CRWMS M&O 1999a. Analysis and Modeling Development Plan (DP) for U0135, Natural 
Analogues for the UZ, Rev. 00. TDP-NBS-HS-000008. Las Vegas, Nevada: CRWMS M&O. 
ACC: MOL.19990826.0108. 
CRWMS M&O 1999b. PSS Activity 6105 Science Support (non-Q). Activity Evaluation. Las 
Vegas, Nevada: CRWMS M&O. ACC: MOL.19990326.0063. 
CRWMS M&O 1999c. License Application Design Selection Report. 
B00000000-01717-4600-00123 Rev.01. Las Vegas, Nevada: CRWMS M&O. ACC: 
MOL.19990917.0120. 
CRWMS M&O 2000. Seepage Calibration Model and Seepage Testing Data. 
MDL-NBS-HS-000004. Las Vegas, Nevada: CRWMS M&O. ACC: MOL.19990721.0521. 
URN-0024. 
DOE 1998. Introduction and Site Characteristics. Volume I of Viability Assessment of a 
Repository at Yucca Mountain. DOE/RW-0508/VI. Washington D.C.: DOE OCRWM. 
ACC: MOL.19981007.0028. 
Doughty, C. 1999. Investigation of Conceptual and Numerical Approaches for Evaluating 
Moisture, Gas, Chemical, and Heat Transport in Fractured Unsaturated Rock. Journal of 
Contaminant Hydrology 38 (13), 69106. New York, New York: Elsevier Science Publishers. 
TIC: 244160. 
Dyer, J.R. 1999. Revised Interim Guidance Pending Issuance of New U.S. Nuclear Regulatory 
Commission (NRC) Regulations (Revision 01, July 22, 1999), for Yucca Mountain, Nevada. 
Letter from J.R. Dyer (DOE) to D.R. Wilkins (CRWMS M&O), September 9, 1999, 
OL&RC:SB-1714, with enclosure, Interim Guidance Pending Issuance of New U.S. Nuclear 
Regulatory Commission (NRC) Regulations (Revision 01). ACC: MOL.19990910.0079. 
Faybishenko, B.; Holland, P.; Mesa, M.; Burgess, D.; Knutson, C.; and Sisson, B. 1998a. 
Lithological Conditions at the Box Canyon Site: Results of Drilling, Coring and Open Borehole 
Measurements19951997 Data Report. Report LBNL-40182. Berkeley, California: Lawrence 
Berkeley National Laboratory. TIC: 245839. 
Faybishenko, B.A.; Salve, R.; Zawislanski, P.; Lee, K.H.; Cook, P.; Freifeld, B.; Williams, K.; and 
Doughty, C. 1998b. Ponded Infiltration Test at the Box Canyon Site: Data Report and 
Preliminary Analysis. Report LBNL-40183. Berkeley, California: Lawrence Berkeley National 
Laboratory. ACC: MOL.19981002.0035. 
Faybishenko, B.; Doughty, C.; Steiger, M.; Long, J.C.S.; Wood, T.R.; Jacobsen, J.S.; Lore, J.; and 
Zawislanski, P.T. 1999. Conceptual Model of the Geometry and Physics of Water Flow in a 
Fractured Basalt Vadose Zone: Box Canyon Site, Idaho. LBNL-42925. Berkeley, California: 
Lawrence Berkeley National Laboratory. TIC: 245840. 
Finsterle, S. 1999. ITOUGH2 Users Guide. Report LBNL-40040. Berkeley, California: 
Lawrence Berkeley National Laboratory. TIC: 243018.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 118 March 2000 
Flint, L.E. 1998. Characterization of Hydrogeologic Units Using Matrix Properties, Yucca 
Mountain, Nevada. Water-Resources Investigations Report 974243. Denver, Colorado: U.S. 
Geological Survey. ACC: MOL.19980429.0512. 
Fridrich, C.J.; Dudley, W.W., Jr.; and Stuckless, J.S. 1994. Hydrogeologic Analysis of the 
Saturated-Zone Ground-water System, under Yucca Mountain, Nevada. Journal of Hydrology, 
154, 133-168. Amsterdam, The Netherlands: Elsevier Science. TIC: 224606. 
Glassley, W.E. and Christensen, B.W. 1992. Water-Rock Interaction in New Zealand 
Hydrothermal Systems: Comparison of Some Simulated and Observed Geochemical Processes. 
High Level Waste Management, Proceedings of the Third International Conference, Las Vegas, 
Nevada, April 1216, 1992, 352356. La Grange Park, Illinois: American Nuclear Society. 
TIC: 204231. 
Goodell P. 1985. Chihuahua City Uranium Province, Chihuahua, Mexico. Uranium Deposits 
in Volcanic Rocks, Proceedings of a Technical Committee Meeting on Uranium Deposits in 
Volcanic Rocks, El Paso, Texas, April 25, 1984, 97124. El Paso, Texas: International Atomic 
Energy Association. TIC: 246156. 
Grossenbacher, K. and Faybishenko, B. 1995. Spacing of Thermally Induced Columnar Joints in 
Basalt: Variation with Depth. LBNL-38060. Berkeley, California: Lawrence Berkeley National 
Laboratory. TIC: on order. 
Hardin, E.L. 1998. Near-Field/Altered Zone Models. Milestone Report SP3100M4. Livermore, 
California: Lawrence Livermore National Laboratory. ACC: MOL.19980504.0577. 
Hevesi, J.A.; Flint, A.L.; and Istock, J.D. 1992. Precipitation Estimation in Mountainous Terrain 
Using Multivariate Geostatistics, Part II: Isohyetal Maps. Journal of Applied Meteorology, 31, 
677688. Boston, Massachusetts: American Meteorological Society. TIC: 225247. 
Huang, K.; Tsang, Y.W.; and Bodvarsson, G.S. 1999. Simultaneous Inversion of Air Injection 
Tests in Fractured Unsaturated Tuff at Yucca Mountain. Water Resources Research, 35 (8), 
23752386. Washington, D.C.: American Geophysical Union. TIC: 245633. 
Ivanovich, M. and Harmon, R.S., eds. 1992. Uranium Series Disequilibrium: Applications to 
Earth, Marine, and Environmental Sciences, 2nd Ed. Oxford, England: Clarendon Press. TIC: 
234680. 
Knutson, C.F.; McCormick, K.A.; Smith, R.P.; Hackett, W.R.; OBrien, J.P.; and Crocker, J.C. 
1990. Fiscal Year 89 Report RWMC Vadose Zone Basalt Characterization. Report 
EG&G-WM-8949. Idaho Falls, Idaho: EG & G Idaho. TIC: 245912. 
Knutson, C.F.; Cox, D.O.; Dooley, K.J.; and Sisson, J.B. 1993. Characterization of Low 
Permeability Media Using Outcrop Measurements. 68th Annual Technical Conference and 
Exhibition of the Society of Petroleum Engineers, October 3-6, 1993, Houston Texas. SPE Paper 
26487. Richardson, Texas: Society of Petroleum Engineers. TIC: 247011.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 119 March 2000 
Krumhansl, J.L. and Stockman, H.W. 1988. Site Selection Criteria and Preliminary Results from 
the Valles Caldera Natural Analog Study. Proceedings of Workshop IV on Flow and Transport 
Through Unsaturated Fractured Rock-Related to High Level Radioactive Waste Disposal, 
Tucson, Arizona, 1988, 249276. Tucson, Arizona: University of Arizona. TIC: on order. 
Ku, T.L.; Luo, S.; Leslie, B.W.; and Hammond, D.E. 1992. Decay-Series Disequilibria Applied 
to the Study of Rock-Water Interaction and Geothermal Systems. Uranium Series 
Disequilibrium: Applications to Earth, Marine, and Environmental Sciences, 2nd Ed. Ivanovich, 
M. and Harmon, R.S., eds., 631-668. New York, New York: Oxford University Press. 
TIC: 234680. 
Leslie, B.; Pearcy, E.; and Prikryl, J. 1993. Oxidative Alteration of Uraninite at the Nopal I 
Deposit, Mexico. Scientific Basis for Nuclear Waste Management XVI, Materials Resources 
Symposium Proceedings, Boston, Massachusetts, November 30December 4, 1992, 294, 505-512. 
Pittsburgh, Pennsylvania: Materials Research Society. TIC: 208880. 
Leslie, B.W.; Pickett, D.A.; and Pearcy, E.C. 1999. Vegetation-Derived Insights on the 
Mobilization and Potential Transport of Radionuclides from the Nopal I Natural Analog Site, 
Mexico. Scientific Basis for Nuclear Waste Management, XXII Symposium Proceedings, Boston, 
Massachusetts, November 30December 4, 1998. Warrendale, Pennsylvania: Materials Research 
Society. (in press). TIC: 246246. 
Lichtner, P.C.; Keating, G.; and Carey, B. 1999. A Natural Analogue for 
Thermal-Hydrological-Chemical Coupled Processes at the Proposed Nuclear Waste Repository 
at Yucca Mountain, Nevada. Report LA-13610-MS. Los Alamos, New Mexico: Los Alamos 
National Laboratory. TIC: 246032. 
Liu, H.H.; Doughty, C.; and Bodvarsson, G.S. 1998. An Active Fracture Model for Unsaturated 
Flow and Transport in Fractured Rocks. Water Resources Research 34 (10), 2633-2646. 
Washington, D.C.: American Geophysical Union. TIC: 243012. 
Ludwig, K.R. and Titterington, D.M. 1994. Calculation of 230Th/238U Isochrons, Ages, and 
Errors. Geochimica et Cosmochimica Acta, 22, 50315042. New York, New York: Pergamon 
Press. TIC: 245769. 
Matyskiela, W. 1997. Silica Redistribution and Hydrologic Changes in Heated Fractured Tuff. 
Geology 25 (12), 11151118. Boulder, Colorado: Geological Society of America. TIC: 236809. 
Meijer, A. 1987. Investigations of Natural Geologic and Geochemical Analogs in Relation to a 
Potential Nuclear Waste Repository at Yucca Mountain, Nevada. Milestone Report R398. 
Albuquerque, New Mexico: Los Alamos National Laboratory. ACC: NNA.19900112.0350. 
Montazer, P. and Wilson, W.E. 1984. Conceptual Hydrologic Model of Flow in the Unsaturated 
Zone, Yucca Mountain, Nevada. Water-Resources Investigations Report 844345. Denver, 
Colorado: U.S. Geological Survey. ACC: NNA.19890327.0051.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 120 March 2000 
Murphy, W. 1995. Natural Analogs for Yucca Mountain. Radwaste Magazine, 2 (6), 44-50. 
LaGrange Park, Illinois: American Nuclear Society. TIC: 237929. 
Murrell, M.T.; Goldstein, S.; and Dixon, P.R. 1997. Uranium Decay Series Mobility from a 
Uranium Ore Deposit: Implications for Nuclear Repository Stability. EOS Transactions, 78 
(46), F788. Washington, D.C.: American Geophysical Union. TIC: 246604 
Pearcy, E.C.; Prikryl, J.D.; Murphy, W.M.; and Leslie, B.W. 1994. Alteration of Uraninite from 
the Nopal I Deposit, Pea Blanca District, Chihuahua, Mexico, Compared to Degradation of 
Spent Nuclear Fuel in the Proposed U.S. High-Level Nuclear Waste Repository at Yucca 
Mountain, Nevada. Applied Geochemistry, 9, 713-732. New York, New York: Elsevier 
Science. TIC: 236934. 
Pearcy, E.C.; Prikryl, J.D.; and Leslie, B.W. 1995. Uranium Transport Through Fractured Silicic 
Tuff and Relative Retention in Areas with Distinct Fracture Characteristics. Applied 
Geochemistry, 10, 685-704. Oxford, UK: Elsevier Science. TIC: 246848. 
Pickett, D.A. and Murphy, W.M. 1997. Isotopic Constraints on Radionuclide Transport at Pea 
Blanca. Seventh EC Natural Analogue Working Group Meeting, Proceedings of an International 
Workshop, Stein am Rhein, Switzerland, October 2830, 1996, van Maravic, H. and Smellie, J., 
eds., 113122. Stein am Rhein, Switzerland: European Commission. TIC: on order. 
Pickett, D.A. and Murphy, W.M. 1999. Unsaturated Zone Waters from the Nopal I Natural 
Analog, Chihuahua, MexicoImplications for Radionuclide Mobility at Yucca Mountain. 
Scientific Basis for Nuclear Waste Management, XXII Symposium Proceedings, Boston, 
Massachusetts, November 30December 4, 1998 556, 809816. Warrendale, Pennsylvania: 
Materials Research Society. TIC: 246426. 
Prikryl, J.D.; Pickett, D.A.; Murphy, W.M.; and Pearcy, E.C. 1997. Migration Behavior of 
Naturally Occurring Radionuclides at the Nopal I Uranium Deposit, Chihuahua, Mexico. 
Journal of Contaminant Hydrology, 26, 6169. New York, New York: Elsevier Science. 
TIC: 242381. 
Pruess, K. 1991. TOUGH2A General Purpose Numerical Simulator for Multiphase Fluid and 
Heat Flow. Report LBL-29400. Berkeley, California: Lawrence Berkeley National Laboratory. 
ACC: NNA.19940202.0088. 
Pruess, K. 1998. On Water Seepage and Fast Preferential Flow in Heterogeneous, Unsaturated 
Rock Fractures. Journal of Contaminant Hydrology, 30 (34), 333362. Amsterdam, The 
Netherlands: Elsevier Science. TIC: 238921. 
Stockman, H.; Krumhansl, J.; Ho, C.; and McConnell, V. 1994. The Valles Natural Analogue 
Project. Report NUREG/CR-6221. Washington, D.C.: U.S. Nuclear Regulatory Commission. 
TIC: 246123.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 121 March 2000 
Su, G.W.; Geller, J.T.; Pruess, K.; and Wen, F. 1999. Experimental Studies of Water Seepage and 
Intermittent Flow in Unsaturated, Rough-Walled Fractures. Water Resources Research, 35 (4), 
10191037. Washington, D.C.: American Geophysical Union. TIC: 245798. 
Tsang, Y.W. 1992. Usage of Equivalent Apertures for Rock Fractures as Derived from 
Hydraulic and Tracer Tests. Water Resources Research, 28 (5), 1451-1455. Washington, D.C.: 
American Geophysical Union. TIC: 245891. 
Wallace, A.B. and Roper, M.W. 1981. Geology and Ore Deposits Along the Northeastern 
Margin, McDermitt Caldera Complex, Oregon. Uranium in Volcanic and Volcaniclastic Rocks: 
AAPG Studies in Geology, 13, 73-80. Goodell, P.C. and Waters, A.C., eds. Tulsa, Oklahoma: 
American Association of Petroleum Geologists. TIC: 245898. 
Wang, J.S.Y. 1991. Propagation of Infiltration Pulses through Unsaturated Tuff Units. in A 
Review of Rainier Mesa Tunnel and Borehole Data and Their Possible Implications to Yucca 
Mountain Site Study Plans. LBL-32068. Berkeley, California: Lawrence Berkeley National 
Laboratory. ACC: NNA.19920506.0020. 
Wang, J.S.Y. 1992. Variations of Hydrological Parameters of Tuff and Soil. High Level 
Radioactive Waste Management, Proceedings of the 3rd Annual International Conference, Las 
Vegas, Nevada, April 1214, 1992, 727731. LaGrange Park, Illinois: American Nuclear 
Society. TIC: 208542. 
Wang, J.S.Y.; Cook, N.G.W.; Wollenberg, H.A.; Carnahan, C.L.; Javandel, I.; and Tsang, C.F. 
1993. Geohydrologic Data and Models of Rainier Mesa and Their Implications to Yucca 
Mountain. High Level Radioactive Waste Management, Proceedings of the 4th Annual 
International Conference, Las Vegas, Nevada, April 2630, 1993, 675681. LaGrange Park, 
Illinois: American Nuclear Society. TIC: 208542. 
Whelan, J.A. and Reed, M.F. 1997. Geostatistical Analysis of Regional Hydraulic Conductivity 
Variations in the Snake River Plain Aquifer, Eastern Idaho. GSA Bulletin, 109 (7), 855-868. 
Boulder, Colorado: Geological Society of America. TIC: 246133. 
WoldeGabriel, G.; Keating, G.N.; and Valentine, G.A. 1999. Effects of Shallow Basaltic 
Intrusion into Pyroclastic Deposits, Grants Ridge, New Mexico, USA. Journal of Volcanology 
and Geothermal Research, 92, 389411. Amsterdam, The Netherlands: Elsevier Science. 
TIC: 246037. 
Wolery, T.J. and Daveler, S.A. 1992. EQ6, A Computer Program for Reaction Path Modeling of 
Aqueous Geochemical Systems: Theoretical Manual, Users Guide, and Related Documentation 
(Version 7.0). Report UCRL-MFA-110662, Pt. IV. Livermore, California: Lawrence Livermore 
National Laboratory. TIC: 205002. 
Wollenberg, H.A. and Flexser, S. 1986. Contact Zones and Hydrothermal Systems as Analogues 
to Repository Conditions. Chemical Geology 55, 345359. Amsterdam, The Netherlands: 
Elsevier Science Publishers. TIC: 246171.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 122 March 2000 
Wong, V. 1998. Gamma-Ray Characterization of Uranium-Series Nuclides and its Application to 
the Study of the Pea Blanca Natural Analog Site, Chihuahua, Mexico. Ph.D. dissertation. El 
Paso, Texas: University of Texas at El Paso. TIC: 245933. 
Wronkiewicz, D.J.; Bates, J.K.; Wolf, S.F.; and Buck, E.C. 1996. Ten-Year Results from 
Unsaturated Drip Tests With UO2 at 90C: Implications for the Corrosion of Spent Nuclear 
Fuel. Journal of Nuclear Materials, 238, 7895. Amsterdam, The Netherlands: Elsevier 
Science. TIC: 243361. 
Xu, T. and Pruess, K. 1998. Coupled Modeling of Non-Isothermal Multi-Phase Flow, Solute 
Transport and Reactive Chemistry in Porous and Fractured Media: 1. Model Development and 
Validation. LBNL-42050. Berkeley, California: Lawrence Berkeley National Laboratory. TIC: 
243735. 
YMP 1998. Repository Safety Strategy: U.S. Department of Energys Strategy to Protect Public 
Health and Safety after Closure of a Yucca Mountain Repository. YMP/96-01, Rev. 2. 
Washington D.C.: DOE OCRWM. ACC: MOL.19980727.0001. 
Zyvoloski, G.A; Dash, Z.V.; and Kelkar, S. 1996. FEHMN 1.0, Finite Element Heat and Mass 
Transfer Code. Technical Report LA-12062-MS, Rev. 1. Albuquerque, New Mexico: Los 
Alamos National Laboratory. ACC: NNA.19910625.0038. 
SOFTWARE CITED 
Software code: TOUGH2 V1.3. STN: 10061-1.3-00. 
Software macro: perm.for V1.0. ACC: MOL.19991011.0224. 
Software macro: plot.for V1.0. ACC: MOL.19991011.0225. 
Software macro: rocktype.for V1.0. ACC: MOL.19991011.0226. 
Software macro: save2tec.for V1.0 ACC: MOL.19991011.0227. 
Software macro: tough2tec.for V1.0. ACC: MOL.19991011.0228. 
Software macro: trans_cal.for V1.0. ACC: MOL.19991011.0229. 
Software macro: weight.for V1.0. ACC: MOL.19991011.0230. 
8.2 CODES, STANDARDS, REGULATIONS AND PROCEDURES 
AP-3.10Q. Analyses And Models. Las Vegas, Nevada: CRWMS M&O. 
ACC: MOL.19990702.0314. 
AP-SI.1Q. Software Management. Las Vegas, Nevada: CRWMS M&O. 
ACC: MOL.19990630.0395.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 123 March 2000 
DOE (U.S. Department of Energy)1998. Quality Assurance Requirements and Description. 
DOE/RW-0333P, Rev 8. Washington D.C.: DOE OCRWM. ACC: MOL.19980601.0022. 
QAP-2-0. Conduct of Activities. Las Vegas, Nevada: CRWMS M&O. 
ACC: MOL.19980826.0209. 
YMP-LBNL-QIP-SI.0, Rev. 4, Mod. 0. Computer Software Qualification. Berkeley, California: 
Lawrence Berkeley National Laboratory. ACC: MOL.19990503.0120. 
8.3 SOURCE DATA, LISTED BY DATA TRACKING NUMBER 
LB990930123122.001. Box Canyon Datasets, Including Fracture/Matrix Properties, Infiltration 
Rates, and Bromide Concentrations. Submittal date: 01/11/2000. 
LB990930123122.002. Model input and output files used to generate figures in AMR U0135. 
Submittal date: 01/11/2000. 
8.4 OUTPUT DATA, LISTED BY DATA TRACKING NUMBER 
LA9909MM122122.001. U-Series Natural Analog Studies at Pea Blanca, Mexico. Submittal 
date: Will be submitted with AMR. 
8.5 SUPPORTING BIBLIOGRAPHY 
Bodvarsson, G.S. and Bandurraga, T.M. 1997. Conceptual Model of Flow and Transport at 
Yucca Mountain. Chapter 2 of The Site-Scale Unsaturated Zone Model of Yucca Mountain, 
Nevada, for the Viability Assessment. Bodvarsson, G.S.; Bandurraga, T.M. and Wu, Y.S., eds. 
Milestone Report SD24UFM4. Berkeley, California: Lawrence Berkeley National Laboratory. 
ACC: MOL.19971014.0232. 
Zyvoloski, G.A.; Robinson, B.A.; Dash, Z.; and.Trease, L.L. 1997. Summary of Models and 
Methods for the FEHM Application, a Finite-Element-Heat and Mass-Transfer Code. Report 
LA-13307-MS. Albuquerque, New Mexico: Los Alamos National Laboratory.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 124 March 2000 
INTENTIONALLY LEFT BLANK

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 125 March 2000 
9. ATTACHMENTS 
Attachment I - Document Input Reference Sheet 
Attachment II - List of Input/Output files for Box Canyon Study (Section 6.5.1.1) 
Attachment III - Pea Blanca Natural Analog Bibliography 
Attachment IV - Derivation of Fracture Continuum Properties 
Attachment V - Software Routines

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 126 March 2000 
INTENTIONALLY LEFT BLANK

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-1 March 2000 
ATTACHMENT IDOCUMENT INPUT REFERENCE SHEET 
DIRS as of the issue date of this AMR. Refer to the DIRS database for the current status of these 
inputs. 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
2a 
1. 
DTN: 
LB990930123122.001. Box 
Canyon Datasets, including 
Fracture/Matrix Properties, 
Infiltration Rates, and 
Bromide Concentrations. 
Submittal date: 01/11/2000. 
Table 6.2.xls 
 all columns 
except for 
model 
calibration 
data. 
Table 6.3.xls 
 entire 
Table 6.4.xls 
 Entire, 
except for 
mean. 
Table 6.5.xls 
 centroid 
of injection 
interval and 
Field Data 
Table 6.6.xls 
 Entire 
Table 6.7.xls 
 Entire 
BromideData 
.xls  Entire 
N/A  
N/Q 
6.5.1.1 
Fracture and matrix 
properties of the Box 
Canyon model. 
Location of borehole 
intersections with active 
water conducting fractures. 
Matrix porosity and 
permeability measurements 
from core samples. 
Fracture permeability 
calibration results from the 
analyzing of the pneumatic 
test data. 
Ponding test infiltration and 
duration times. 
Ponding test infiltration 
rates 
Bromide concentration 
during the 97-1 to 97-4 
infiltration tests 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-2 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
2. 
LB990930123122.002. 
Model input and output files 
used to generate figures in 
AMR U0135. Submittal 
date: 01/11/2000. 
Input Files N/A-N/Q 6.5.1.1 
Input files for modeling 
results at Box Canyon 
N/A N/A N/A N/A 
3. 
Ahlers, C.F.; Finsterle, S.; 
and Bodvarsson, G.S. 1999. 
Characterization and 
Prediction of Subsurface 
Pneumatic Response at 
Yucca Mountain, Nevada. 
Journal of Contaminant 
Hydrology 38 (1-3), 4768. 
Amsterdam, The 
Netherlands: Elsevier 
Science. TIC: 244160. 
8.2 and 9 
N/A  
Reference 
only 
6.2 
Pneumatic data showing 
faults as fast flow 
pathways in PTn and 
TSw 
N/A N/A N/A N/A 
4. 
Alba, L.A. and Chavez, R. 
1974. K-Ar Ages of 
Volcanic Rocks from the 
Sierra Pena Blanca, 
Chihuahua, Mexico. 
Isochron/West, 10, 2123. 
Socorro, New Mexico: 
Bureau of Mines and 
Mineral Resources. TIC: 
246110. 
Entire 
N/A  
Reference 
only 
6.5.2.1.3.1 
K-Ar ages of Nopal and 
Escuadra Formations 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-3 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
5. 
Alexander, D.H. and Van 
Luik, A.E. 1991. Natural 
Analogue Studies Useful in 
Validating Regulatory 
Compliance Analyses. 
Validation of Geosphere 
Flow and Transport Models 
(GEOVAL), Proceedings of 
a NEA/SKI Symposium, 
Stockholm, Sweden, May 
1417, 1990, 589597. 
Paris, France: Organization 
for Economic Cooperation 
and Development. TIC: 
246109. 
Entire 
N/A  
Reference 
only 
6.5.2.2 
McDermitt caldera U 
deposits proposed as 
potential YM analogs 
N/A N/A N/A N/A 
6. 
Allard, T. and Muller, J.P. 
1998. Kaolinite as an In 
Situ Dosimeter for Past 
Radionuclide Migration at 
the Earth's Surface. 
Applied Geochemistry, 13 
(6), 751765. Oxford, 
United Kingdom: Elsevier 
Science. TIC: 246131. 
pp. 759- 
764 
N/A  
Reference 
only 
6.5.2.1.4.1.3 
Use of electron 
paramagnetic resonance 
to show transport and 
accumulation of U at 
Pena Blanca 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-4 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
7. 
Baehr, A.L. and Hult, M.F. 
1991. Evaluation of 
Unsaturated Zone Air 
Permeability Through 
Pneumatic Tests. Water 
Resources Research, 27 
(10), 2605-26127. 
Washington, D.C.: 
American Geophysical 
Union. TIC: 245788. 
Entire 
N/A  
Reference 
only 
6.5.1.1.4 
Reference to analytical 
solution for interpreting 
pneumatic test. 
N/A N/A N/A N/A 
8. 
Bandurraga, T.M. and 
Bodvarsson, G.S. 1999. 
Calibrating Hydrogeologic 
Parameters for the 3-D Site- 
Scale Unsaturated Zone 
Model of Yucca Mountain, 
Nevada. Journal Of 
Contaminant Hydrology 38 
(13), 25-46. Amsterdam, 
The Netherlands: Elsevier 
Science Publishers. TIC: 
244160. 
Entire 
N/AReference 
only 
6.5.1.1.1 
Description of 
conceptual model used at 
Yucca Mountain. 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-5 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
9. 
Benito, P.H.; Cook, P.; 
Faybishenko, B.; Freifeld, 
B.; and Doughty, C. 1998. 
Box Canyon Pneumatic 
Connectivity Study: 
Preliminary Data Analysis. 
LBNL-38060. Berkeley, 
California: Lawrence 
Berkeley National 
Laboratory. TIC: on order. 
Entire 
N/A  
Reference 
only 
6.5.1.1.4 
Detailed description of 
all pneumatic tests 
conducted at Box 
Canyon. 
N/A N/A N/A N/A 
10. 
Bish, D.L. and Aronson, 
J.L. 1993. 
Paleogeothermal and 
Paleohydrologic Conditions 
in Silicic Tuff from Yucca 
Mountain, Nevada. Clays 
and Clay Minerals, 41 (2), 
148-161. Long Island City, 
New York: Pergamon 
Press. TIC: 224613. 
Entire 
N/A  
Reference 
only 
6.5.3.2 
Study of YM as selfanalog 
using mineralogy 
and temperature data 
N/A N/A N/A N/A 
11. 
Brookins, D.G. 1984. 
Natural Analogs. 
Geochemical Aspects of 
Radioactive Waste 
Disposal, 197231. New 
York, New York: Springer- 
Verlag. TIC: 206675. 
197-231 
N/A  
Reference 
only 
6.5.3.2 
Description of Alamosa 
River stock as 
hydrothermal analog for 
geologic repository 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-6 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
12. 
Brookins, D.G.1986. 
Natural Analogues for 
Radwaste Disposal: 
Elemental Migration in 
Igneous Contact Zones. 
Chemical Geology, 55, 337- 
344. Amsterdam, The 
Netherlands: Elsevier 
Science Publishers. TIC: 
246170. 
Entire 
N/A  
Reference 
only 
6.5.3.2 
Various igneous contact 
zones as possible 
analogs to radionuclide 
transport at a geologic 
repository 
N/A N/A N/A N/A 
13. 
Bruton, C.J.; Glassley, 
W.E.; and Bourcier, W.L. 
1993. Testing 
Geochemical Modeling 
Codes using New Zealand 
Hydrothermal Systems. 
Proceedings of the Topical 
Meeting on Site 
Characterization and Model 
Validation: FOCUS 93, 
September 26-29, 1993, Las 
Vegas, Nevada, 240245. 
La Grange Park, Illinois: 
American Nuclear Society. 
TIC: 102245. 
Entire 
N/A  
Reference 
Only 
6.5.3.3 
Use of mineral data from 
New Zealand geothermal 
field to test EQ3/6 code 
and database 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-7 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
14. 
Bruton, C.J.; Glassley, 
W.E.; and Meike, A. 1995. 
Geothermal Areas as 
Analogs to Chemical 
Processes in the Near-Field 
and Altered Zone of the 
Potential Yucca Mountain, 
Nevada Repository. UCRLID-
119842. Livermore, 
California: Lawrence 
Livermore National 
Laboratory. ACC: 
MOL.19960408.0126. 
Entire 
N/A  
Reference 
only 
6.5.3.3 
Selection criteria for 
choice of geothermal 
analog for YM 
repository 
N/A N/A N/A N/A 
15. 
Carey, J.W.; Chipera, S.J.; 
Vaniman, D.T.; and Bish, 
D.L. 1997. Three- 
Dimensional Mineralogic 
Model of Yucca Mountain, 
Nevada, Rev. 1.1, Draft R0. 
Milestone Report 
SP32B5M4. Los Alamos, 
New Mexico: Los Alamos 
National Laboratory. ACC: 
MOL.19980520.0170. 
Entire 
N/A  
Reference 
only 
6.5.3.2 
Likely mineral phases to 
form at YM under 
repository heating 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-8 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
16. 
Carroll, S.; Mroczek, E.; 
Bourcier, B.; Alai, M.; and 
Ebert, M. 1995. 
Comparison of Field and 
Laboratory Precipitation 
Rates of Amorphous Silica 
from Geothermal Waters at 
100oC. Milestone Report 
MOL207. Livermore, 
California: Lawrence 
Livermore National 
Laboratory. ACC: 
MOL.19960415.0465. 
Entire 
N/A  
Reference 
only 
6.5.3.3 
Comparison of field and 
laboratory rates of 
amorphous silica 
precipitation from 
geothermal waters at 100 
degrees Celsius. 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-9 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
17. 
Castor, S.B.; Henry, C.D.; 
and Shevenell, L.A. 1996. 
Volcanic Rock-Hosted 
Uranium Deposits in 
Northwestern Nevada and 
Southeastern Oregon 
Possible Sites for Studies of 
Natural Analogues for the 
Potential High-Level 
Nuclear Waste Repository 
at Yucca Mountain, Nevada. 
Report from Mackey School 
of Mines. Reno, Nevada: 
University of Nevada. 
ACC: 
MOL.19960927.0026. 
Entire 
N/A  
Reference 
only 
6.5.2.2 
Summary of available 
data on uranium deposits 
in northwestern Nevada 
and southeastern Oregon 
N/A N/A N/A N/A 
18. 
Crowe, B.; Self, S.; 
Vaniman, D.; Amos, R.; and 
Perry, F. 1983. Aspects of 
Potential Magmatic 
Disruption of a High-Level 
Radioactive Waste 
Repository in Southern 
Nevada. Journal of 
Geology, 91, 259-276. 
Chicago, Illinois: 
University of Chicago Press. 
TIC: 216959. 
Section on 
characterization 
of 
NTS 
intrusive 
bodies 
N/A  
Reference 
only 
6.5.3.2 
Depth of emplacement 
of NTS igneous intrusive 
bodies 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-10 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
19. 
CRWMS M&O (Civilian 
Radioactive Waste 
Management System 
Management and Operating 
Contractor) 1998a. Yucca 
Mountain Site Description. 
Book 3-Section 6, 7. 
B00000000-01717-5700- 
00019-00. Las Vegas, 
Nevada: CRWMS M&O. 
ACC: 
MOL.19981021.0043. 
p. F6.1-75 
to F6.1-76 
N/A  
Reference 
only 
6.5.3.2 
Figure showing potential 
mineral alteration zones 
at Yucca Mt. 
N/A N/A N/A N/A 
20. 
CRWMS M&O 1998b. 
Thermal Hydrology. 
Chapter 3 of Total System 
Performance Assessment- 
Viability Assessment (TSPAVA) 
Analyses Technical 
Basis Document. 
B00000000-01717-4301- 
00003-00. Washington 
D.C.: DOE OCRWM. 
ACC: 
MOL.19980724.0392. 
Ch. 3, p. 
189-191 
N/A - 
Reference 
only 
7.1.1 
Handling of coupled 
processes in TSPA-VA 
calculations 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-11 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
21. 
CRWMS M&O 1998c. 
Unsaturated Zone 
Radionuclide Transport. 
Chapter 7 of Total System 
Performance Assessment- 
Viability Assessment (TSPAVA) 
Analyses Technical 
Basis Document. 
B00000000-01717-4301- 
00003-00. Washington 
D.C.: DOE OCRWM. 
ACC: 
MOL.19980724.0396. 
Ch. 7, p. 
102 
N/A - 
Reference 
only 
7.1.1 
Radionuclide transport 
processes that were not 
covered in TSPA-VA 
N/A N/A N/A N/A 
22. 
CRWMS M&O 1998d. 
Summary and Conclusions. 
Chapter 11 of Total System 
Performance Assessment- 
Viability Assessment (TSPAVA) 
Analyses Technical 
Basis Document. 
B00000000-01717-4301- 
00003-00. Washington 
D.C.: DOE OCRWM. 
ACC: 
MOL.19981008.0011. 
Ch. 11, p. 
58 
N/A  
Reference 
only 
7.1.1 
Role of seepage in 
TSPA-VA calculations. 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-12 March 2000 
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Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
23. 
CRWMS M&O 1999a. 
Analysis and Modeling 
Development Plan (DP) for 
U0135, Natural Analogues 
for the UZ, Rev. 00. TDPNBS-
HS-000008. Las 
Vegas, Nevada: CRWMS 
M&O. ACC: 
MOL.19990826.0108. 
Entire 
N/A  
Reference 
only 
2 Plan N/A N/A N/A N/A 
24. 
CRWMS M&O 1999b. PSS 
Activity 6105 Science 
Support (non-Q). Activity 
Evaluation. Las Vegas, 
Nevada: CRWMS M&O. 
ACC: 
MOL.19990326.0063. 
Entire 
N/A  
Reference 
Only 
2 Activity Evaluation N/A N/A N/A N/A 
25. 
CRWMS M&O 1999c. 
License Application Design 
Selection Report. 
B00000000-01717-4600- 
00123 Rev.01. Las Vegas, 
Nevada: CRWMS M&O. 
ACC: 
MOL.19990917.0120. 
Entire 
N/A  
Reference 
Only 
6.5.3.2 
Thermal loading 
considered for EDA-II 
design 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-13 March 2000 
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ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
26. 
CRWMS M&O 2000. 
Seepage Calibration Model 
and Seepage Testing Data. 
MDL-NBS-HS-000004. 
Las Vegas, Nevada: 
CRWMS M&O. ACC: 
MOL.19990721.0521. 
URN-0024. 
70 
N/A  
Reference 
Only 
6.2 
Seepage threshold value 
for YM 
N/A N/A N/A N/A 
27. 
DOE 1998. Introduction 
and Site Characteristics. 
Volume I of Viability 
Assessment of a Repository 
at Yucca Mountain. 
DOE/RW-0508/VI. 
Washington D.C.: DOE 
OCRWM. ACC: 
MOL.19981007.0028. 
Chapter 2 
N/A  
Reference 
Only 
6.2 
6.5.1.2 
Conceptual model of UZ 
flow processes. 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-14 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
28. 
Doughty, C. 1999. 
Investigation of 
Conceptual and Numerical 
Approaches for Evaluating 
Moisture, Gas, Chemical, 
and Heat Transport in 
Fractured Unsaturated 
Rock. Journal of 
Contaminant Hydrology, 38 
(1-3), 69-106. New York, 
New York: Elsevier 
Science Publishers. TIC: 
244160. 
Entire 
N/A  
Reference 
Only 
6.5.1.1.3 
Sensitivity analysis for 
scaling of fracturematrix 
interfacial area. 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-15 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
29. 
Dyer, J.R. 1999. Revised 
Interim Guidance Pending 
Issuance of New U.S. 
Nuclear Regulatory 
Commission (NRC) 
Regulations (Revision 01, 
July 22, 1999), for Yucca 
Mountain, Nevada. Letter 
from J.R. Dyer (DOE) to 
D.R. Wilkins (CRWMS 
M&O), September 9, 1999, 
OL&RC:SB-1714, with 
enclosure, Interim 
Guidance Pending Issuance 
of New U.S. Nuclear 
Regulatory Commission 
(NRC) Regulations 
(Revision 01). ACC: 
MOL.19990910.0079. 
Entire 
N/AReference 
only 
4.2 Interim Guidance N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-16 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
30. 
Faybishenko, B.; Holland, 
P.; Mesa, M.; Burgess, D.; 
Knutson, C.; and Sisson, B. 
1998a. Lithological 
Conditions at the Box 
Canyon Site: Results of 
Drilling, Coring and Open 
Borehole 
Measurements.19951997 
Data Report. Report 
LBNL-40182. Berkeley, 
California: Lawrence 
Berkeley National 
Laboratory. TIC: 245839. 
Entire 
N/AReference 
only 
6.5.1.1.2 
Description of core logs 
and other details 
pertaining to Box 
Canyon site 
N/A N/A N/A N/A 
31. 
Faybishenko, B.A.; Salve, 
R.; Zawislanski, P.; Lee, 
K.H.; Cook, P.; Freifeld, B.; 
Williams, K.; and Doughty, 
C. 1998b. Ponded 
Infiltration Test at the Box 
Canyon Site: Data Report 
and Preliminary Analysis. 
Report LBNL-40183. 
Berkeley, California: 
Lawrence Berkeley National 
Laboratory. ACC: 
MOL.19981002.0035. 
Entire 
N/A  
Reference 
only 
6.5.1.1.5 
Data source for the 96-1 
data set in DTN: 
LB990930123122.001. 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-17 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
32. 
Faybishenko, B.; Doughty, 
C.; Steiger, M.; Long, 
J.C.S.; Wood, T.R.; 
Jacobsen, J.S.; Lore, J.; and 
Zawislanski, P.T. 1999. 
Conceptual Model of the 
Geometry and Physics of 
Water Flow in a Fractured 
Basalt Vadose Zone: Box 
Canyon Site, Idaho. LBNL- 
42925. Berkeley, California: 
Lawrence Berkeley National 
Laboratory. TIC: 245840. 
Entire 
N/A  
Reference 
only 
6.5.1.1 
Outlines the general 
conceptual model 
developed prior to this 
study to explain field 
data collected at the Box 
Canyon site. It is also 
source for the 97-1 to 
97-4 data set, in DTN: 
LB990930123122.001. 
N/A N/A N/A N/A 
33. 
Finsterle, S. 1999. 
ITOUGH2 Users Guide. 
Report LBNL-40040. 
Berkeley, California: 
Lawrence Berkeley National 
Laboratory. ACC: 
MOL.19980429.0512. 
Entire 
N/A  
Reference 
only 
6.5.1.1 
Inverse modeling 
methodology 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-18 March 2000 
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Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
34. 
Flint, L.E. 1998. 
Characterization of 
Hydrogeologic Units Using 
Matrix Properties, Yucca 
Mountain, Nevada. Water- 
Resources Investigations 
Report 974243. Denver, 
Colorado: U.S. Geological 
Survey. ACC: 
MOL.19980429.0512. 
Entire 
N/AReference 
only 
6.2 
UZ matrix properties, 
Yucca Mt. 
N/A N/A N/A N/A 
35. 
Fridrich, C.J.; Dudley, 
W.W., Jr.; and Stuckless, 
J.S. 1994. Hydrogeologic 
Analysis of the Saturated- 
Zone Ground-water System, 
under Yucca Mountain, 
Nevada. Journal of 
Hydrology, 154, 133-168. 
Amsterdam, The 
Netherlands: Elsevier 
Science. TIC: 224606. 
Entire 
N/A  
Reference 
only 
6.2 
Conceptual model of SZ 
transport; role of faults 
as barriers or pathways 
to flow between UZ and 
SZ 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-19 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
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1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
36. 
Glassley, W.E. and 
Christensen, B.W. 1992. 
Water-Rock Interaction in 
New Zealand Hydrothermal 
Systems: Comparison of 
Some Simulated and 
Observed Geochemical 
Processes. High Level 
Waste Management, 
Proceedings of the Third 
International Conference, 
Las Vegas, Nevada, April 
1216, 1992, 352356. La 
Grange Park, Illinois: 
American Nuclear Society. 
TIC: 204231. 
Entire 
N/A  
Reference 
only 
6.5.3.3 
Application of New 
Zealand geothermal data 
to testing EQ3/6 code 
and database 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-20 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
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ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
37. 
Goodell P. 1985. 
Chihuahua City Uranium 
Province, Chihuahua, 
Mexico. Uranium 
Deposits in Volcanic Rocks, 
Proceedings of a Technical 
Committee Meeting on 
Uranium Deposits in 
Volcanic Rocks, El Paso, 
Texas, April 25, 1984, 97 
124. El Paso, Texas: 
International Atomic Energy 
Association. TIC: 246156. 
Entire 
N/A  
Reference 
only 
6.5.2.2 
Proposal of Pena Blanca 
as a good analog to 
Yucca Mountain 
N/A N/A N/A N/A 
38. 
Grossenbacher, K. and 
Faybishenko, B. 1995. 
Spacing of Thermally 
Induced Columnar Joints in 
Basalt: Variation with 
Depth. LBNL-38060. 
Berkeley, California: 
Lawrence Berkeley National 
Laboratory. TIC: on order. 
Entire 
N/A  
Reference 
only 
6.5.1.1.2 
Data source for vertical 
and horizontal fracture 
spacings. 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-21 March 2000 
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1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
39. 
Hardin, E.L. 1998. Near- 
Field/Altered Zone Models. 
Milestone Report 
SP3100M4. Livermore, 
California: Lawrence 
Livermore National 
Laboratory. ACC: 
MOL.19980504.0577. 
p. 5.57- 
5.67 
N/A  
Reference 
only 
6.5.3.2 
Potential formation of 
silica cap at YM 
N/A N/A N/A N/A 
40. 
Hevesi, J.A.; Flint, A.L.; 
and Istock, J.D. 1992. 
Precipitation Estimation in 
Mountainous Terrain Using 
Multivariate Geostatistics, 
Part II: Isohyetal Maps. 
Journal of Applied 
Meteorology, 31, 677-688. 
Boston, Massachusetts: 
American Meteorological 
Society. TIC: 225247. 
Entire 
N/A  
Reference 
only 
6.2 
Calculation of 
precipitation at YM 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-22 March 2000 
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ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
41. 
Huang, K.; Tsang, Y.W.; 
and Bodvarsson, G.S. 1999. 
Simultaneous Inversion of 
Air Injection Tests in 
Fractured Unsaturated Tuff 
at Yucca Mountain. Water 
Resources Research, 35 (8), 
2375-2386. Washington, 
D.C.: American 
Geophysical Union. TIC: 
245633. 
Entire 
N/A  
Reference 
only 
6.5.1.1.4 
Outlines the 
methodology used at 
Yucca Mountain for 
using pneumatic tests to 
determine fracture 
permeabilities. 
N/A N/A N/A N/A 
42. 
Ivanovich, M. and Harmon, 
R.S., eds. 1992. Uranium 
Series Disequilibrium: 
Applications to Earth, 
Marine, and Environmental 
Sciences, 2nd Ed. Oxford, 
England: Clarendon Press. 
TIC: 234680. 
5558, 
7778, 
460461, 
631668 
N/A  
Reference 
only 
6.5.2.1.4.2.3 
Calculated model of U- 
234 ages 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-23 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
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1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
43. 
Knutson, C.F.; McCormick, 
K.A.; Smith, R.P.; Hackett, 
W.R.; OBrien, J.P.; and 
Crocker, J.C. 1990. Fiscal 
Year 89 Report RWMC 
Vadose Zone Basalt 
Characterization. Report 
EG&G-WM-8949. Idaho 
Falls, Idaho: EG & G 
Idaho. TIC: 245912. 
Entire 
N/A  
Reference 
only 
6.5.1.1.2 
Data source for matrix 
porosity and 
permeability. 
N/A N/A N/A N/A 
44. 
Knutson, C.F.; Cox, D.O.; 
Dooley, K.J.; and Sisson, 
J.B. 1993. 
Characterization of Low 
Permeability Media Using 
Outcrop Measurements. 
68th Annual Technical 
Conference and Exhibition 
of the Society of Petroleum 
Engineers, October 3-6, 
1993, Houston Texas. SPE 
Paper 26487. Richardson, 
Texas: Society of Petroleum 
Engineers. TIC: 247011. 
Entire 
N/A  
Reference 
only 
6.5.1.1.1 
Geological description of 
Box Canyon site. 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-24 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
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ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
45. 
Krumhansl, J.L. and 
Stockman, H.W. 1988. 
Site Selection Criteria and 
Preliminary Results from 
the Valles Caldera Natural 
Analog Study. 
Proceedings of Workshop 
IV on Flow and Transport 
Through Unsaturated 
Fractured RockRelated to 
High Level Radioactive 
Waste Disposal, Tucson, 
Arizona, 1988, 249-276. 
Tucson, Arizona: 
University of Arizona. TIC: 
on order. 
Entire 
N/A  
Reference 
only 
6.5.3.2 
Alteration effects at 
contact between tuff and 
obsidian, Valles Caldera 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-25 March 2000 
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DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
46. 
Ku, T.L.; Luo, S.; Leslie, 
B.W.; and Hammond, D.E. 
1992. Decay-Series 
Disequilibria Applied to the 
Study of Rock-Water 
Interaction and Geothermal 
Systems. Uranium Series 
Disequilibrium: 
Applications to Earth, 
Marine, and Environmental 
Sciences, 2nd Ed. 
Ivanovich, M. and Harmon, 
R.S., eds. New York, New 
York: Oxford University 
Press. TIC: 234680. 
Entire 
N/A  
Reference 
only 
6.5.2.1.6.2 
Use of U-series 
disequilibrium in natural 
analog approach to study 
of rock-water systems 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-26 March 2000 
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1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
47. 
Leslie, B.; Pickett, D.; and 
Pearcy, E. 1999. 
Vegetation-Derived 
Insights on the Mobilization 
and Potential Transport of 
Radionuclides from the 
Nopal I Natural Analog 
Site, Mexico. Scientific 
Basis for Nuclear Waste 
Management, XXII 
Symposium Proceedings, 
Boston, Massachusetts, 
November 30  December 4, 
1998. Warrendale, 
Pennsylvania: Materials 
Research Society. TIC: 
246246. 
Entire 
N/A  
Reference 
only 
6.5.2.1.4.2.6 
U-enriched plants at 
Nopal I 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-27 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
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ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
48. 
Leslie, B.W.; Pearcy, E.A.; 
and Prikryl, J.C. 1993. 
Oxidative Alteration of 
Uraninite at the Nopal I 
Deposit, Mexico. 
Scientific Basis for Nuclear 
Waste Management XVI, 
Materials Resources 
Symposium Proceedings, 
Boston, Massachusetts, 
November 30  December 4, 
1992, 294, 505. Pittsburgh, 
Pennsylvania: Materials 
Research Society. TIC: 
208880. 
Entire 
N/A  
Reference 
only 
6.5.2.1.4.1.1 
Comparison of alteration 
sequence at Nopal I with 
that from laboratory 
experiments 
N/A N/A N/A N/A 
49. 
Lichtner, P.C.; Keating, G.; 
and Carey, B. 1999. A 
Natural Analogue for 
Thermal-Hydrological- 
Chemical Coupled 
Processes at the Proposed 
Nuclear Waste Repository 
at Yucca Mountain, Nevada. 
LA-13610-MS. Los 
Alamos, New Mexico: Los 
Alamos National 
Laboratory. TIC: 246032. 
Entire 
N/A  
Reference 
only 
5
6.5.3.2 
7.2.1 
Calculated volumes of 
minerals precipitated 
from boiling water in 
fractures 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-28 March 2000 
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ANL-NBS-HS-000007/Rev. 00 
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Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
50. 
Liu, H.H.; Doughty, C.; and 
Bodvarsson, G.S. 1998. 
"An Active Fracture Model 
for Unsaturated Flow and 
Transport in 
Fractured Rocks." Water 
Resources Research, 34, 
(10), 2633-2646. 
Washington, D.C.: 
American Geophysical 
Union. 
TIC: 243012. 
Entire 
N/A  
Reference 
only 
6.5.1.1.3 Active fracture model N/A N/A N/A N/A 
51. 
Ludwig, K.R. and 
Titterington, D.M. 1994. 
Calculation of 230Th /U 
Isochrons, Ages, and 
Errors. Geochimica et 
Cosmochimica Acta, 22, 
5031-5042. New York, 
New York: Pergamon 
Press. TIC: 245769. 
Entire 
N/A  
Reference 
only 
6.5.2.1.4.2.3 
Methodology for 
calculation of 230Th/234U 
isochrons and source of 
errors 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-29 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
52. 
Matyskiela, W. 1997. 
Silica Redistribution and 
Hydrologic Changes in 
Heated Fractured Tuff. 
Geology 25 (12),1115-1118. 
Boulder, Colorado: 
Geological Society of 
America. TIC: 236809. 
Entire 
N/A  
Reference 
only 
6.5.3.2 
Analog study of fossil 
hydrothermal systems at 
Paiute Ridge, NV 
N/A N/A N/A N/A 
53. 
Meijer, A. 1987. 
Investigations of Natural 
Geologic and Geochemical 
Analogs in Relation to a 
Potential Nuclear Waste 
Repository at Yucca 
Mountain, Nevada. 
Milestone Report R398. 
Albuquerque, New Mexico: 
Los Alamos National 
Laboratory. ACC: 
NNA.19900112.0350. 
Entire 
N/A  
Reference 
only 
6.5.3.3 
Attributes of 
Yellowstone 
hydrothermal system that 
compare with potential 
conditions at a YM 
repository 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-30 March 2000 
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DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
54. 
Montazer, P. and Wilson, 
W.E. 1984. Conceptual 
Hydrologic Model of Flow 
in the Unsaturated Zone, 
Yucca Mountain, Nevada. 
Water-Resources 
Investigations Report 84 
4345. Denver, Colorado: 
U.S. Geological Survey. 
ACC: 
NNA.19890327.0051. 
Entire 
N/AReference 
only 
6.2 
Conceptual hydrologic 
model of UZ flow, 
Yucca Mt. 
N/A N/A N/A N/A 
55. 
Murphy, W. 1995. Natural 
Analogs for Yucca 
Mountain. Radwaste 
Magazine, 2 (6), 44-50. 
LaGrange Park, Illinois: 
American Nuclear Society. 
TIC: 237929. 
Entire 
N/A  
Reference 
only 
6.5.2.1.2 
Pena Blanca as a good 
analog to YM - rationale 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-31 March 2000 
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DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
56. 
Murrell, M.T.; Goldstein, 
S.; and Dixon, P.R. 1997. 
Uranium Decay Series 
Mobility from a Uranium 
Ore Deposit: Implications 
for Nuclear Repository 
Stability. EOS 
Transactions, 78 (46), F788. 
Washington, D.C.: 
American Geophysical 
Union. TIC: 246604. 
Entire 
N/AReference 
only 
6.5.2.1 1997 U-series results N/A N/A N/A N/A 
57. 
Pearcy, E.C.; Prikryl, J.D.; 
Murphy, W.M.; and Leslie, 
B.W. 1994. Alteration of 
Uraninite from the Nopal I 
Deposit, Pea Blanca 
District, Chihuahua, 
Mexico, Compared to 
Degradation of Spent 
Nuclear Fuel in the 
Proposed U.S. High-Level 
Nuclear Waste Repository 
at Yucca Mountain, 
Nevada. Applied 
Geochemistry, 9, 713-732. 
New York, New York: 
Elsevier Science. TIC: 
236934. 
Entire 
N/A  
Reference 
only 
6.5.2.1.4.2.3 
6.5.2.1 
4.2.4 
Ages of hydrologic 
disturbance at Nopal I 
based on U-Th data 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-32 March 2000 
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DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
58. 
Pearcy, E.C.; Prikryl, J.D.; 
and Leslie, B.W. 1995. 
Uranium Transport 
Through Fractured Silicic 
Tuff and Relative Retention 
in Areas with Distinct 
Fracture Characteristics. 
Applied Geochemistry, 10, 
685-704. Oxford, United 
Kingdom: Elsevier Science. 
TIC: 246848. 
Entire 
N/A  
Reference 
only 
6.5.2.1.4.2.3 
U and Th isotopic 
compositions for Nopal I 
samples 
N/A N/A N/A N/A 
59. 
Pickett, D.A. and Murphy, 
W.M. 1997. Isotopic 
Constraints on Radionuclide 
Transport at Pea Blanca. 
Seventh EC Natural 
Analogue Working Group 
Meeting, Proceedings of an 
International Workshop, 
Stein am Rhein, 
Switzerland, October 3830, 
1996, 113122. Stein am 
Rhein, Switzerland: 
European Commission. 
TIC: on order. 
Entire, 
Table 2 
N/A  
Reference 
only 
6.5.2.1.4.1.1 
U-series data collected at 
Nopal I 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-33 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
60. 
Pickett, D.A. and Murphy, 
W.M. 1999. Unsaturated 
Zone Waters from the Nopal 
I Natural Analog, 
Chihuahua, 
Mexico.Implications for 
Radionuclide Mobility at 
Yucca Mountain. 
Scientific Basis for Nuclear 
Waste Management, XXII 
Symposium Proceedings, 
Boston, Massachusetts, 
November 30  December 4, 
1998 556, 809-816. 
Warrendale, Pennsylvania: 
Materials Research Society. 
TIC: 246424. 
Entire 
N/A  
Reference 
only 
6.5.2.1.4.2.3 
Composition of Nopal I 
waters 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-34 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
61. 
Prikryl, J.D.; Pickett, D.A.; 
Murphy, W.M.; and Pearcy, 
E.C. 1997. Migration 
Behavior of Naturally 
Occurring Radionuclides at 
the Nopal I Uranium 
Deposit, Chihuahua, 
Mexico. Journal of 
Contaminant Hydrology, 26, 
61-69. New York, New 
York: Elsevier Science. 
TIC: 242381. 
Entire 
N/A  
Reference 
only 
6.5.2.1.4.1.1 
U in secondary minerals 
at Nopal I - mineralogy 
N/A N/A N/A N/A 
62. 
Pruess, K. 1991. 
TOUGH2.A General 
Purpose Numerical 
Simulator for Multiphase 
Fluid and Heat Flow. 
Report LBL-29400. 
Berkeley, California: 
Lawrence Berkeley National 
Laboratory. ACC: 
NNA.19940202.0088. 
Entire 
N/A  
Reference 
only 
6.5.1.1 TOUGH2 reference. N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-35 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
63. 
Pruess, K. 1998. On Water 
Seepage and Fast 
Preferential Flow in 
Heterogeneous, Unsaturated 
Rock Fractures. Journal of 
Contaminant Hydrology, 30 
(34), 333362. 
Amsterdam, The 
Netherlands: Elsevier 
Science. TIC: 238921. 
Entire 
N/A  
Reference 
only 
6.5.1.1.5.1 
Description of water 
flow channeling in 
variably saturated rough 
walled fractures. 
N/A N/A N/A N/A 
64. 
Stockman, H.; Krumhansl, 
J.; Ho, C.; and McConnell, 
V. 1994. The Valles 
Natural Analogue Project. 
Report NUREG/CR-6221. 
Washington , D.C.: U.S. 
Nuclear Regulatory 
Commission. TIC: 246123. 
Entire 
N/AReference 
only 
6.5.3.2 
Study of contact 
alteration between 
obsidian and tuff, Valles 
Caldera. 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-36 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
65. 
Su, G.W.; Geller, J.T.; 
Pruess, K.; and Wen, F. 
1999. Experimental 
Studies of Water Seepage 
and Intermittent Flow in 
Unsaturated, Rough-Walled 
Fractures. Water 
Resources Research, 35 (4), 
10191037. Washington, 
D.C.: American 
Geophysical Union. TIC: 
245798. 
Entire 
N/A  
Reference 
only 
6.5.1.1.5.1 
Description of water 
flow channeling in 
variably saturated rough 
walled fractures 
N/A N/A N/A N/A 
66. 
Tsang, Y.W. 1992. Usage 
of Equivalent Apertures 
for Rock Fractures as 
Derived from Hydraulic and 
Tracer Tests. 
Water Resources Research, 
28 (5), 1451-1455. 
Washington, D.C.: 
American Geophysical 
Union. TIC: 245891. 
Entire 
N/A  
Reference 
only 
5
6.5.1.1.5.1 
Definition of average 
fracture aperture as 
measured by various 
methods 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-37 March 2000 
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1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
67. 
Wallace, A.B. and Roper, 
M.W. 1981. Geology and 
Ore Deposits Along the 
Northeastern Margin, 
McDermitt Caldera 
Complex, Oregon. 
Uranium in Volcanic and 
Volcaniclastic Rocks: 
AAPG Studies in Geology, 
13, 73-80. Goodell, P.C. 
and Waters, A.C., eds. 
Tulsa, Oklahoma: 
American Association of 
Petroleum Geologists. TIC: 
245898. 
Entire 
N/A  
Reference 
only 
6.5.2.2 
Geology and ore 
deposits at northeast 
margin of McDermitt 
Caldera 
N/A N/A N/A N/A 
68. 
Wang, J.S.Y. 1991. 
Propagation of Infiltration 
Pulses through Unsaturated 
Tuff Units. in A Review of 
Rainier Mesa Tunnel and 
Borehole Data and Their 
Possible Implications to 
Yucca Mountain Site Study 
Plans. LBL-32068. 
Berkeley, California: 
Lawrence Berkeley National 
Laboratory. ACC: 
Entire 
N/A  
Reference 
only 
6.5.1.2 
Hydrogeology and 
structural features of 
Rainier Mesa 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-38 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
69. 
Wang, J.S.Y. 1992. 
Variations of Hydrological 
Parameters of Tuff and 
Soil. High Level 
Radioactive Waste 
Management, Proceedings 
of the 3rd Annual 
International Conference, 
Las Vegas, Nevada, April 
12-14, 1992, 727-731. 
LaGrange Park, Illinois: 
American Nuclear Society. 
TIC: 208542. 
Entire 
N/A  
Reference 
only 
6.5.1.2 
Flow parameters in 
Apache Leap Tuff 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-39 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
70. 
Wang, J.S.Y.; Cook, 
N.G.W.; Wollenberg, H.A.; 
Carnahan, C.L.; Javandel, I.; 
and Tsang, C.F. 1993. 
Geohydrologic Data and 
Models of Rainier Mesa and 
Their Implications to Yucca 
Mountain. High Level 
Radioactive Waste 
Management, Proceedings 
of the 4th Annual 
International Conference, 
Las Vegas, Nevada, April 
26-30, 1993, 675-681. 
LaGrange Park, Illinois: 
American Nuclear Society. 
TIC: 208542. 
Entire 
N/A  
Reference 
only 
6.5.1.2 
36Cl measurements in 
Rainier Mesa tunnels; 
comparison of Rainier 
Mesa and YM 
hydrostratigraphy 
N/A N/A N/A N/A 
71. 
Whelan, J.A. and Reed, 
M.F. 1997. Geostatistical 
Analysis of Regional 
Hydraulic Conductivity 
Variations in the Snake 
River Plain Aquifer, Eastern 
Idaho. GSA Bulletin, 109 
(7), 855-868. Boulder, 
Colorado: Geological 
Society of America. TIC: 
246133. 
Entire 
N/AReference 
only 
6.5.1.1.1 
Geological description of 
Box Canyon site. 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-40 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
72. 
WoldeGabriel, G.; Keating, 
G.N.; and Valentine, G.A. 
1999. Effects of Shallow 
Basaltic Intrusion into 
Pyroclastic Deposits, Grants 
Ridge, New Mexico, USA. 
Journal of Volcanology and 
Geothermal Research, 92, 
389-411. Amsterdam, The 
Netherlands: Elsevier 
Science. TIC: 246037. 
Entire 
N/A  
Reference 
only 
6.5.3.2 
Effects of basaltic 
intrusion on host rock 
TH-THC properties 
N/A N/A N/A N/A 
73. 
Wolery, T.J. and Daveler, 
S.A. 1992. EQ6, A 
Computer Program for 
Reaction Path Modeling of 
Aqueous Geochemical 
Systems: Theoretical 
Manual, Users Guide, and 
Related Documentation 
(Version 7.0). Report 
UCRL-MFA-110662, Pt. 
IV. Livermore, California: 
Lawrence Livermore 
National Laboratory. TIC: 
205002. 
Entire 
N/A  
Reference 
only 
6.5.3.3 
Example of reaction path 
code used by others for 
thermochemical 
modeling 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-41 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
74. 
Wollenberg, H.A. and 
Flexser, S. 1986. Contact 
Zones and Hydrothermal 
Systems as Analogues to 
Repository Conditions. 
Chemical Geology 55, 345- 
359. Amsterdam, The 
Netherlands: Elsevier 
Science Publishers. TIC: 
246171. 
Entire 
N/A  
Reference 
only 
6.5.3.2 
Transport of U and trace 
elements away from 
igneous contact zones 
N/A N/A N/A N/A 
75. 
Wong, V. 1998. Gamma- 
Ray Characterization of 
Uranium-Series Nuclides 
and its Application to the 
Study of the Pea Blanca 
Natural Analog Site, 
Chihuahua, Mexico. Ph.D. 
dissertation. El Paso, 
Texas: University of Texas 
at El Paso. TIC: 245933. 
Entire 
N/A  
Reference 
only 
6.5.2.1.4.1.2 
U-series disequilibrium 
using gamma 
spectrometry 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-42 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
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1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
76. 
Wronkiewicz, D.J.; Bates, 
J.K.; Wolf, S.F.; and Buck, 
E.C. 1996. Ten-Year 
Results from Unsaturated 
Drip Tests With UO2 at 
90C: Implications for the 
Corrosion of Spent Nuclear 
Fuel. Journal of Nuclear 
Materials, 238, 7895. 
Amsterdam, The 
Netherlands: Elsevier 
Science. TIC: 243361. 
Entire 
N/A  
Reference 
only 
6.5.2.1.3 
Secondary U mineral 
phases formed in 
laboratory drip tests 
N/A N/A N/A N/A 
77. 
Xu, T. and Pruess, K. 1998. 
Coupled Modeling of Non- 
Isothermal Multi-Phase 
Flow, Solute Transport and 
Reactive Chemistry in 
Porous and Fractured 
Media: 1. Model 
Development and 
Validation. LBNL-42050. 
Berkeley, California: 
Lawrence Berkeley National 
Laboratory. TIC: 243735. 
Entire 
N/AReference 
only 
7.1 
Example reference of 
coupled process 
modeling code 
N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment I-43 March 2000 
OFFICE OF CIVILIAN RADIOACTIVE WASTE MANAGEMENT 
DOCUMENT INPUT REFERENCE SHEET 
1. Document Identifier No./Rev.: 
ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
78. 
YMP (Yucca Mountain 
Project) 1998. Repository 
Safety Strategy: U.S. 
Department of Energys 
Strategy to Protect Public 
Health and Safety after 
Closure of a Yucca 
Mountain Repository. 
YMP/96-01, Rev. 2. 
Washington D.C.: DOE 
OCRWM. ACC: 
MOL.19980727.0001. 
Entire 
N/A - 
Reference 
only 
7.1.1 
Role of natural analogs 
in DOE/YMP safety 
strategy 
N/A N/A N/A N/A 
79. 
Zyvoloski, G.A; Dash, Z.V.; 
and Kelkar, S. 1996. 
FEHMN 1.0, Finite Element 
Heat and Mass Transfer 
Code. Technical Report 
LA-12062-MS, Rev. 1. 
Albuquerque, New Mexico: 
Los Alamos National 
Laboratory. ACC: 
NNA.19910625.0038. 
Entire 
N/A  
Reference 
only 
6.5.3.2 
Reference to code used 
by others in modeling 
hydrothermal processes 
N/A N/A N/A N/A 
80. Software code: TOUGH2 
V1.3. STN: 10061-1.3-00. 
Entire N/AQ 6.5.1.1 
Modeling code used in 
6.5.1.1 of this report 
N/A N/A N/A N/A 
81. 
Software macro: perm.for 
V1.0. ACC: 
MOL.19991011.0224. 
Entire N/AQ 6.5.1.1 Software use N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
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ANL-NBS-HS-000007/Rev. 00 
Change: Title: 
Natural Analogs for the Unsaturated Zone 
Input Document 8. TBV Due To 
2. Technical Product Input Source 
Title and Identifier(s) with Version 
3. Section 
4. Input 
Status 
5. Section 
Used in 6. Input Description 
7. 
TBV/TBD 
Priority Unqual. 
From 
Uncontrolled 
Source 
Unconfirmed 
82. 
Software macro: plot.for 
V1.0. ACC: 
MOL.19991011.0225. 
Entire N/AQ 6.5.1.1 Software use N/A N/A N/A N/A 
83. 
Software macro: 
rocktype.for V1.0. ACC: 
MOL.19991011.0226. 
Entire N/AQ 6.5.1.1 Software use N/A N/A N/A N/A 
84. 
Software macro: 
save2tec.for V1.0 ACC: 
MOL.19991011.0227. 
Entire N/AQ 6.5.1.1 Software use N/A N/A N/A N/A 
85. 
Software macro: 
tough2tec.for V1.0. ACC: 
MOL.19991011.0228. 
Entire N/AQ 6.5.1.1 Software use N/A N/A N/A N/A 
86. 
Software macro: 
trans_cal.for V1.0. ACC: 
MOL.19991011.0229. 
Entire N/AQ 6.5.1.1 Software use N/A N/A N/A N/A 
87. 
Software macro: weight.for 
V1.0. ACC: 
MOL.19991011.0230. 
Entire N/AQ 6.5.1.1 Software use N/A N/A N/A N/A

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment II-1 March 2000 
ATTACHMENT II. 
LIST OF INPUT/OUTPUT FILES FOR BOX CANYON STUDY (SECTION 6.5.1.1) 
The following files were used during the Box Canyon simulations and submitted to the TDMS 
under DTN: LB990930123122.002. 
Pneumatic Injection Analysis 
Parameter file for software routine rocktype.for used to create TOUGH2 (TOUGH2 V1.3, 
STN: 10061-1.3-00) input 
C:\803D-74\FractureNetwork\grid\rocktype\rocktype_pneumatic.prm 
TOUGH2 input and output files 
C:\803D-74\results\pneumatic\pneumatic.zip 
Infiltration Analysis 
The following files were used for the 1-d infiltration calibration and are parameter files for 
software routine rocktype.for used to create TOUGH2 input. 
C:\803D-74\FractureNetwork\grid\rocktype\rocktype_steady_e1.prm 
\rocktype_trans_e1.prm 
\obstimes_e1.dat 
C:\803D-74\FractureNetwork\grid\rocktype\rocktype_steady_i1.prm 
\rocktype_trans_i1.prm 
\obstimes_i1.dat 
C:\803D-74\FractureNetwork\grid\rocktype\rocktype_steady_i2.prm 
\rocktype_trans_i2.prm 
\obstimes_i2.dat 
C:\803D-74\FractureNetwork\grid\rocktype\rocktype_steady_i3.prm 
\rocktype_trans_i3.prm 
\obstimes_i3.dat 
C:\803D-74\FractureNetwork\grid\rocktype\rocktype_steady_t5.prm 
\rocktype_trans_t5.prm

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment II-2 March 2000 
\obstimes_t5.dat 
C:\803D-74\FractureNetwork\grid\rocktype\rocktype_steady_t6.prm 
\rocktype_trans_t6.prm 
\obstimes_t6.dat 
C:\803D-74\FractureNetwork\grid\rocktype\rocktype_steady_t7.prm 
\rocktype_trans_t7.prm 
\obstimes_t7.dat 
C:\803D-74\FractureNetwork\grid\rocktype\rocktype_steady_t8.prm 
\rocktype_trans_t8.prm 
\obstimes_t8.dat 
C:\803D-74\FractureNetwork\grid\rocktype\rocktype_steady_t9.prm 
\rocktype_trans_t9.prm 
\obstimes_t9.dat 
C:\803D-74\FractureNetwork\grid\rocktype\pond_96-1_97-1-4.dat 
The steady file set up the steady-state conditions while the trans file sets up 96-1 to 97-1 to 
97-4 infiltration conditions. The obstimes file set up TOUGH2 output times while the pond 
file was used to establish the infiltration rates. 
Output from TOUGH2 after processing by software routine trans_cal.for is provided in the 
following directories: 
C:\803D-74\FractureNetwork\grid\trans_cal\e1\trans_cal.dat 
\i1\trans_cal.dat 
\i2\trans_cal.dat 
\i3\trans_cal.dat 
\t5\trans_cal.dat 
\t6\trans_cal.dat 
\t7\trans_cal.dat

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment II-3 March 2000 
\t8\trans_cal.dat 
\t9\trans_cal.dat 
and the final Tecplot (a standard graphics program) input file created by plot.for using the above 
files is: 
C:\803D-74\FractureNetwork\grid\trans_cal\plot\plot.dat 
The following files were used in the 3-d infiltration simulations and are parameter files for 
software routine rocktype.for used to create TOUGH2 input. 
C:\803D-74\FractureNetwork\grid\rocktype\rocktype_steady_3d.prm 
\rocktype_trans_96-1_3d.prm 
\pond_96-1.dat 
\rocktype_trans_97-1-4_3d.prm 
\pond_97-1_97-4.dat 
\obstimes_3d.dat 
The resulting TOUGH2 input/output is located in: 
C:\803D-74\results\infiltration\steady\steady.zip 
C:\803D-74\results\infiltration\96-1\96-1.zip 
C:\803D-74\results\infiltration\97-1\97-1.zip 
The software routine weight.for was used to create Tecplot input files to visualize the weighting 
factors used to condition the hydrogeological properties in the fracture continuum. All files are 
located in: 
C:\803D-74\FractureNetwork\grid\WeightingFactor 
The software routine perm.for was used to locate the packer centroid of each pneumatic test in the 
Box Canyon grid. All relevant files are located in: 
C:\803D-74\FractureNetwork\grid\perm 
The softare routine save2tec.for and tough2tec.for were used to extract output from TOUGH2 and 
reformat it for visualization using Tecplot. All relevant files are located in: 
C:\803D-74\FractureNetwork\grid\save2tec 
C:\803D-74\Fracture Network/grid/tough2tec

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment III-1 March 2000 
ATTACHMENT III. 
PEA BLANCA NATURAL ANALOG BIBLIOGRAPHY 
Alexander, W. and McKinley, I. 1992. A Review of the Application of Natural Analogs in 
Performance Assessment: Improving Models of Radionuclide Transport in Groundwaters. 
Journal of Geochemical Exploration, 46, 83115. Amsterdam, Netherlands. 
Allard, T. and Muller, J.P. 1998. Kaolinite as an In Situ Dosimeter for Past Radionuclide 
Migration at the Earth's Surface. Applied Geochemistry, 13 (6), 751765. Oxford, United 
Kingdom: Pergamon Press. 
Bell, R. 1981. Geology at Central Sierra Pea Blanca. Masters Thesis. El Paso, Texas: 
University of Texas. 
Cardenas-Flores, D. 1985. Volcanic Stratigraphy and U-Mo Mineralization of the Sierra de Pea 
Blanca District, Chihuahua, Mexico. Uranium Deposits in Volcanic Rocks, Proceedings of a 
Technical Committee Meeting on Volcanic Rocks, El Paso, Texas, April 2-5, 1984, 125136. 
IAEA-TC-490/31. Vienna, Austria: International Atomic Energy Agency. 
Clark K.; Goodell. P.; and Lovejoy. E. 1983. Geology and Mineral Resources of North Central 
Chihuahua. Guidebook for the 1983 Field Conference, El Paso Geological Society, October 7-9, 
1983. 
Finch, R.J. and Ewing, R. 1992. The Corrosion of Uraninite Under Oxidizing Conditions. 
Journal of Nuclear Materials, 190, 133156. Amsterdam, Netherlands: Elsevier Science 
Publishers. 
George-Aniel, B.; Leroy, J.; and Poty, B. 1985. Uranium Deposit of the Sierra Pea Blanca. 
Uranium Deposits in Volcanic Rocks, Proceedings of a Technical Committee Meeting on Volcanic 
Rocks, El Paso, Texas, April 2-5, 1984, 175186. IAEA-TC-490/8. Vienna, Austria: 
International Atomic Energy Agency. 
George-Aniel, B.; Leroy, J.; and Poty, B. 1991. Volcanogenic Uranium Mineralizations in the 
Sierra Pea Blanca District, Chihuahua, Mexico: Three Genetic Models. Economic Geology, 86 
(2), 233248. 
Goodell P. 1980. Geology of the Pea Blanca Uranium Deposits, Chihuahua, Mexico. 
Uranium Deposits in Volcanic Rocks: Symposium Proceedings of the Annual Meeting of the 
Southwest Section of the American Association of Petroleum Geologists, El Paso, Texas, 1980, 
13, 275292. Goodell, P. and Waters, A., eds. Tulsa, Oklahoma: American Association of 
Petroleum Geologist. 
Goodell, P. 1985a. Classification and Model of Uranium in Volcanic Deposits. Uranium 
Deposits in Volcanic Rocks, Proceedings of a Technical Committee Meeting on Volcanic Rocks, El 
Paso, Texas, April 2-5, 1984, 116. IAEATC-490/8. Vienna, Austria: International Atomic 
Energy Agency.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment III-2 March 2000 
Goodell, P. 1985b. Chihuahua City Uranium Province, Chihuahua, Mexico. Uranium Deposits 
in Volcanic Rocks, Proceedings of a Technical Committee Meeting on Volcanic Rocks, El Paso, 
Texas, April 2-5, 1984, 97124. IAEATC-490/19. Vienna, Austria: International Atomic Energy 
Agency. 
Green, R.; Rice, G.; and Meyer-James, K. 1995. Hydraulic Characterization of Hydrothermally 
Altered Nopal Tuff. NUREG/CR-6356, CNWRA 94-027. San Antonio, Texas: Center for 
Nuclear Waste Regulatory Analyses. 
IAEA 1989. Natural Analogs in Performance Assessment for the Disposal of Long-Lived 
Radioactive Wastes. IAEA Technical Report Series No 304, 151. Vienna, Austria: International 
Atomic Energy Agency. 
Ildefonse, P.; Muller, J.P.; Clozel, B.; and Calas, G. 1990a. Study of Two Alteration Systems as 
Natural Analogues for Radionuclides Release and Migration. Engineering Geology, 29 (4), 
413439. 
Ildefonse, P.; Muller, J.P.; and Callas, G. 1990b. Assessment of Radionuclide Migration in 
Natural Analogues by Radiation-Induced Centers in Kaolinite. Symposium Proceedings of the 
Scientific Basis for Nuclear Waste Management XIV, 212, 474. Abrajano, T. and Johnson, L., eds. 
Pittsburgh, Pennsylvania: Materials Research Society. 
Ildefonse, P.; Muller, J.P.; Clozel, B.; and Calas, G. 1991. Record of Past Contact Between 
Altered Rocks and Radioactive Solutions through Radiation-Induced Defects in Kaolinite. 
Symposium Proceedings of the Scientific Basis for Nuclear Waste Management XV, 212, 749. 
Pittsburgh, Pennsylvania: Materials Research Society. 
Latham, A. and Schwarcz, H. 1989. Review of the Modeling of Radionuclide Transport From 
U-Series Disequilibria and of Its Use in Assessing the Safe Disposal of Nuclear Waste in 
Crystalline Rock. Applied Geochemistry, 4 (5), 527537. 
Leslie, B.; Pearcy, E.; and Prikryl, J. 1993a. Geochemical Natural Analogs, in NRC High-Level 
Radioactive Waste Research at CNWRA, January-June 1992. NUREG/CR-5817, CNWRA 
92-01S, 3 (1), San Antonio, Texas: Center for Nuclear Waste Regulatory Analyses. 
Leslie, B.; Pearcy, E.; and Prikryl, J. 1993b. Oxidative Alteration of Uraninite at the Nopal I 
Deposit, Mexico. Symposium Proceedings of the Scientific Basis for Nuclear Waste 
Management XVII, 294, 505512. Pittsburgh, Pennsylvania: Materials Research Society. 
Leslie, B.; Pickett, D.A.; and Pearcy, E. 1999. Vegetation-Derived Insights on the Mobilization 
and Potential Transport of Radionuclides from the Nopal I Natural Analog Site, Mexico. 
Symposium Proceedings of the Scientific Basis for Nuclear Waste Management, XXII, Boston, 
Massachusetts, November 30-December 4, 1998. Wronkiewicz, D. and Lee, J., eds. Pittsburgh, 
Pennsylvania: Materials Research Society.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment III-3 March 2000 
Lueth, V. and Heizler, M. 1997. Ar-40/Ar-39 Age and Origin of Jarosite Mineralization at the 
Ansonburg District, New Mexico. Annual Meeting, New Mexico Geological Society, April 18, 
1997. 
Lueth, V.; Goodell, P.; Heizler, M.; and Peters, L. 1998. Geochemistry, Geochronology, and 
Tectonic Implications of Jarosite Mineralization in the Northern Franklin Mountains, Doa Ana 
County, New Mexico. New Mexico Geological Guidebook, 309. Las Cruces, New Mexico: 
New Mexico Geological Society. 
Magonthier, M.C. 1985. Caracteristicas Petrograficas y Geoquimicas de las Unidades 
Ignimbriticas Portadoras de Mineralizacion de Uranio de la Sierra Pea Blanca. Uranium 
Deposits in Volcanic Rocks, Proceedings of a Technical Committee Meeting on Volcanic Rocks, El 
Paso, Texas, April 2-5, 1984, 137150. IAEATC-490/7. Vienna, Austria: International Atomic 
Energy Agency. 
Magonthier, M.C. 1987. Relations Entre Les Mineralisations Duranium de la Sierra Pea 
Blanca (Mexique) et les Ignimbrites Porteuses. Bulletin of Mineralogy, 110, 305. 
McKinley, I. and Alexander, W. 1993. Assessment of Radionuclide Retardation: Uses and 
Abuses of Natural Analog Studies. Journal of Contaminant Hydrology, 13 (1-4), 249259. 
Amsterdam, Netherlands: Elsevier Science Publishers. 
Meyer, K. 1995. Hydraulic Characterization of Hydrothermally Altered Nopal Tuff. Thesis 
Dissertation. San Antonio, Texas. The University of Texas. 
Miranda, M.; Martinez, J.; and Olvera, L. 1985. Emanometria de Radon en el Distrito Uranifero 
de Sierra Pea Blanca y en Ostras Areas Volcanicas de Chihuahua, Mexico. Uranium Deposits 
in Volcanic Rocks, Symposium Proceedings of a Technical Committee Meeting on Volcanic Rocks, 
El Paso, Texas, April 2-5, 1984, 151160. IAEATC-490/21. Vienna, Austria: International 
Atomic Energy Agency. 
Mitchell, S.; Goodell, P.; LeMone, D.; and Pingitore, N. 1980. Uranium Mineralization of Sierra 
Gomez, Chihuahua, Mexico. Uranium Deposits in Volcanic Rocks: Symposium Proceedings of 
the Southwest Section of the American Association of Petroleum Geologists, El Paso, Texas, 1980, 
13, 293310. Goodell, P. and Waters, A., eds. Tulsa, Oklahoma: American Association of 
Petroleum Geologists. 
Muller, J.P.; Ildefonse, P.; and Calas, G. 1990. Paramagnetic Defect Centers in Hydrothermal 
Kaolinite from an Altered Tuff in the Nopal Uranium Deposit, Chihuahua, Mexico. Clays and 
Clay Minerals, 38, 600608. 
Murphy, W.; Pearcy, E.; and Goodell, P. 1991. Possible Analog Research Sites for the Proposed 
High Level Nuclear Waste Repository in Hydrologically Unsaturated Tuff at Yucca Mountain, 
Nevada. Nuclear Science and Technology: Proceedings of the Fourth Natural Analog Working 
Group Meeting and Poos de Caldas Project Final Workshop, June, 18-22, 1990, Pitlochry, 
Scotland, 267276. Report EUR-13014-EN. Luxembourg, Luxembourg: Commission of the 
European Communities.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment III-4 March 2000 
Murphy, W. 1992. Natural Analog Studies for Geological Disposal of Nuclear Waste. 
Technology Today, June, 16-21. San Antonio, Texas: Southwest Research Institute. 
Murphy, W. and Pearcy, E. 1992. Source-Term Constraints for the Proposed Repository at Yucca 
Mountain, Nevada, Derived from the Natural Analog at Pea Blanca, Mexico. Symposium 
Proceedings from Scientific Basis for Nuclear Waste Management XV, 257, 521527. Sombret, 
C.G., ed. Pittsburgh, Pennsylvania: Materials Research Society. 
Murphy, W.M. and Kovach, L.A. 1993. The Role of Natural Analogs in Geologic Disposal of 
High-Level Nuclear Waste, 1113. Report CNWRA 93-020. San Antonio, Texas: Center for 
Nuclear Waste Regulatory Analyses. 
Murphy, W.; Pearcy, E.; and Goodell, P. 1993. Performance Assessment Significance of Natural 
Analog Studies at Pea Blanca, Mexico, and at Santorini, Greece. Nuclear Science and 
Technology: Proceedings of the Fourth Natural Analog Working Group Meeting and Alligator 
River Analog Final Workshop, June 18-22, 1993, Pitlochry, Scotland, 219224. Cme, B. and 
Chapman, N.A., eds. Report EUR-13014-EN. Luxembourg, Luxembourg: Commission of the 
European Communities. 
Murphy, W. and Pearcy, E. 1994. Performance Assessment Significance of Natural Analog 
Studies at Pea Blanca , Mexico, and at Santorini, Greece. Nuclear Science and Technology: 
Proceedings of the Fifth Analog Working Group Meeting, October 5-9, 1994, Toledo, Spain, 219. 
Von Maravic, H. and Smellie, J.A.T., eds. Report EUR-15176-EN. Luxembourg, Luxembourg: 
Commission of the European Communities. 
Murphy, W. 1995a. Effects of Carbon System Geochemistry on Radionuclide Migration at the 
Proposed Nuclear Waste Repository at Yucca Mountain, Nevada, USA. Migration Conference 
St. Malo, France, 1995, 52. 
Murphy, W. 1995b. Natural Analogs for Yucca Mountain. Radwaste Magazine, 2 (6), 4550. 
La Grange Park, Illinois: American Nuclear Society. 
Murphy, W. 1996. Retrograde Solubilities of Source Term Phases. Symposium Proceedings 
from Scientific Basis for Nuclear Waste Management XIX, 465, 713. Pittsburgh, Pennsylvania: 
Materials Research Society. 
Murphy, W.; Pearcy, E.; and Pickett, D. 1997a. Natural Analog Studies at Pea Blanca and 
Santorini. Nuclear Science and Technology: Proceedings from the Seventh Natural Analog 
Working Group Meeting, October 28-30, 1997, Stein am Rhein, Switzerland, 105112. Von 
Maravic, H. and Smellie, J.A.T., eds. Report EUR-17851-EN. Luxembourg, Luxembourg: 
Commission of the European Communities. 
Murphy, W.; Pearcy, E.; and Pickett, D. 1997b. Radionuclide Transport from Mined Uranium 
Ore at Pea Blanca. Proceedings of the Fourth International Conference on Tailings and Mine 
Waste '97, Fort Collins, Colorado, 401404. Rotterdam, Netherlands: A.A. Balkema.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment III-5 March 2000 
Murphy, W.; Pearcy, E.; Green, R.; Prikryl, J.; Mohanty, S.; Leslie, B.; Nedungadi, A. 1998. A 
Test of Long-Term Predictive Geochemical Transport Modeling at the Akrotiri Archaeological 
Site. Journal of Contaminant Hydrology, 29 (3), 245279. Amsterdam, Netherlands: Elsevier 
Science Publishers. 
Murphy, W. and Codell, R. 1999. Alternate Source Term Models for Yucca Mountain 
Performance Assessment Based on Natural Analog Data and Secondary Mineral Solubility. 
Proceedings from Scientific Basis for Nuclear Waste Management XXII, 556, 713. Pittsburgh, 
Pennsylvania: Materials Research Society. 
Pearcy, E. and Murphy, W. 1990a. Geochemical Natural Analogs: Report on Research Activities 
for Calendar Year, 1990. NUREG/CR-5817. San Antonio, Texas: Center for Nuclear Waste 
Regulatory Analyses. 
Pearcy, E. 1990. Geochemical Natural Analogs: Report on Research Activities for the Quarter 
April 1 through June 30, 1990. Patrick, W., ed. CNWRA 90-02Q. San Antonio, Texas: Center 
for Nuclear Waste Regulatory Analyses. 
Pearcy, E. 1991. Oxidative Alteration of Uraninite in a Silicic Tuffaceous Environment. 
Geological Society of America Abstracts with Program, 23, A383. Denver, Colorado: Geological 
Society of America. 
Pearcy, E. and Murphy, W. 1991. Geochemical Natural Analogs: Report on Research Activities 
for the Quarter July 1 through September 30, 1991. Patrick, W., ed. CNWRA 91-03Q. San 
Antonio, Texas: Center for Nuclear Waste Regulatory Analyses. 
Pearcy, E.; Murphy, W.; Green, R.; Leslie, B.; Prikryl, J. 1991a. NRC High-Level Radioactive 
Waste Research at CNWRA, Calendar Year 1991. NUREG/CR-5817, CNWRA 91-01A. San 
Antonio, Texas: Center for Nuclear Waste Regulatory Analyses. 
Pearcy, E.; Murphy, W.; Prikryl, J. 1991b. Geochemical Natural Analogs: Report on Research 
Activities for the Quarter April 1 through June 30, 1991. Patrick, W., ed. CNWRA 91-02Q. San 
Antonio, Texas: Center for Nuclear Waste Regulatory Analyses. 
Pearcy, E. 1993. Crystal Chemistry and Structures of Uraninite from the Nopal I Deposit, Pea 
Blanca District, Mexico. Geological Society of America Abstracts with Program, 25, A382. 
Denver, Colorado: Geological Society of America. 
Pearcy, E. and Leslie, B. 1993. Geochemical Natural Analog Research: NRC High-Level 
Radioactive Research at CNWRA, January through June 1993. Sagar, B., ed. CNWRA 93-01S. 
San Antonio, Texas: Center for Nuclear Waste Regulatory Analyses. 
Pearcy, E.; Murphy, W.; Green, R.; Leslie, B.; and Prikryl, J. 1993. Geochemical Natural Analog 
Research: NRC High-Level Radioactive Research at CNWRA, Calendar Year 1991. Patrick, W., 
ed. NUREG/CR-5817- Vol. 2, CNWRA 91-01A. San Antonio, Texas: Center for Nuclear Waste 
Regulatory Analyses.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment III-6 March 2000 
Pearcy, E. 1994a. Fracture Transport of Uranium at the Nopal I Analog Site. CNWRA 94-011. 
San Antonio, Texas: Center for Nuclear Waste Regulatory Analyses. 
Pearcy, E. 1994b. Geochemical Natural Analog Research: NRC High-Level Radioactive 
Research at CNWRA, January through June 1994. CNWRA 94-01S. San Antonio, Texas: 
Center for Nuclear Waste Regulatory Analyses. 
Pearcy, E. and Manaktala, H. 1994. Nuclear Fuel Corrosion over Millennia Interpreted Using 
Geologic Data. Annual Conference of the National Association of Corrosion 
Engineers-Proceedings-Corrosion 94, 129/1-129/8. 
Pearcy, E.; Murphy, W.; Prikryl, J.; and Leslie, B. 1994. Alteration of Uraninite from the Nopal 
I Deposit, Pea Blanca District, Chihuahua, Mexico, Compared to Degradation of Spent Nuclear 
Fuel in the Proposed U.S. High-Level Waste Repository at Yucca Mountain, Nevada. Journal of 
Applied Geochemistry, 9, 713732. Amsterdam, Netherlands: Elsevier Science Publishers. 
Pearcy, E.; Prikryl, J.; and Leslie, B. 1995. Uranium Transport through Fractured Silicic Tuff 
and Relative Retention in Areas with Distinct Fracture Characteristics. Journal of Applied 
Geochemistry, 10, 685704. Amsterdam, Netherlands: Elsevier Science Publishers. 
Petit, J.C. 1990. Migration of Radionuclides in the Geosphere: What Can We Learn from 
Natural Analogs? Radiochimica Acta, 51 (4), 181188. Oxford, United Kingdom: Pergamon 
Press. 
Pickett, D.; Prikryl, J.; Murphy, W.; and Pearcy, E. 1996. Uranium-Series Disequilibria at the 
Nopal I Uranium Deposit, Pea Blanca District, Chihuahua, Mexico: Implications for Episodic 
Radionuclide Transport at a Geologic Repository for High Level Nuclear Waste. EOS 
Transactions of the American Geophysical Union, 77 (17), 594. Washington, D.C.: American 
Geophysical Union. 
Pickett, D. and Murphy, W. 1997. Isotopic Constraints on Radionuclide Transport at Pea 
Blanca. Nuclear Science and Technology: Proceedings of the Seventh Natural Analog Working 
Group Meeting, Stein am Rhein, Switzerland, October 28-30, 1996, 113122. EUR-17851-EN. 
Von Maravic, H. and Smellie, J., eds. Luxembourg: Commission of the European Communities. 
Pickett, D. and Murphy, W. 1999. Unsaturated Zone Waters from the Nopal I Natural Analog, 
Chihuahua, Mexico - Implications for Radionuclide Mobility at Yucca Mountain. Symposium 
Proceedings of the Scientific Basis for Nuclear Waste Management, Boston, Massachusetts. 
Pittsburgh, Pennsylvania: Materials Research Society. (in press). 
Prikryl, J. 1994. The Role of Secondary Mineral Formation on Uranium Retardation and 
Transport at the Nopal I Deposit, Pea Blanca District, Chihuahua, Mexico. Geological Society 
of America Abstracts with Program, 26, A441. Denver, Colorado: Geological Society of 
America. 
Prikryl, J.; Pearcy, E.; and Pickett, D. 1995a. Migration Behavior of Naturally Occurring 
Radionuclides at the Nopal I Uranium Deposit, Chihuahua, Mexico. Chemistry and Migration 

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment III-7 March 2000 
Behaviour of Actinides and Fission Products in the Geosphere, 47. Migration Conference, St. 
Malo, France. Del Nero, M. and Fanghnel, eds. St. Malo, France: Institut de Physique 
Nucleaire and Forschungszentrum Karlsruhe. 
Prikryl, J.; Pickett, D.; and Pearcy, E. 1995b. Evidence for Uranium Mobilization and Retention 
on Fe-Oxides/Hydroxides at the Nopal I Uranium Deposit. Geological Society of America, 
Abstracts with Program, 27, A420. Denver, Colorado: Geological Society of America. 
Prikryl, J.; Pickett, D.; and Pearcy, E. 1995c. Geochemical Natural Analog Research: NRC 
High-Level Radioactive Research at CNWRA, January through June 1995. CNWRA 95-01S. 
San Antonio, Texas: Center for Nuclear Waste Regulatory Analyses. 
Prikryl, J.; Pickett, D.; and Pearcy, E. 1995d. NRC High-Level Radioactive Waste Research at 
CNWRA, July through December 1995. CNWRA 95-02S. San Antonio, Texas: Center for 
Nuclear Waste Regulatory Analyses. 
Prikryl, J.; Pickett, D.; Murphy, W.; and Pearcy, E. 1997. Migration Behavior of Naturally 
Occurring Radionuclides at the Nopal I Uranium Deposit Chihuahua, Mexico. Journal of 
Contaminant Hydrology, 26 (1-4), 6169. Amsterdam, Netherlands: Elsevier Science Publishers. 
Reyes-Cortes, I.A. 1997. Geologic studies in the Sierra de Pea Blanca, Chihuahua, Mexico. 
Ph.D. Dissertation. El Paso, Texas: University of Texas. 
Reyes-Cortes, I.A. 1985. Deposito de Molibdeno Associado con Uranio en Pea Blanca, 
Mexico. Uranium Deposits in Volcanic Rocks, Proceedings of a Technical Committee Meeting 
on Volcanic Rocks, El Paso, Texas, April 2-5, 1984, 161174. IAEATC-490/16. Vienna, Austria: 
International Atomic Energy Agency. 
Wilson, C.N. 1991. Results from Long-Term Dissolution Tests Using Oxidized Spent Fuel. 
Symposium Proceedings of the Scientific Basis for Nuclear Waste Management XIV, 212, 197. 
Pittsburgh, Pennsylvania: Materials Research Society. 
Wong, V. 1994. Nopal I Uranium at Pea Blanca District, Chihuahua, Mexico: A Study of 
Radionuclide Migration in a Natural Analog to Yucca Mountain, Nevada. Masters Thesis. El 
Paso, Texas: University of Texas. 
Wong, V.; Anthony, E.; and Goodell, P. 1996. Nopal I Uranium Deposit: A Study of 
Radionuclide Migration. High-Level Radioactive Waste Management, Proceedings of the 
Seventh Annual International Conference, April 29  May 3, 1996, Las Vegas, Nevada, 4345. La 
Grange Park, Illinois: American Nuclear Society. 
Wong, V.; Anthony, E.; and Goodell, P. 1997. Application of Natural Analogs to Potential 
Radwaste Repositories. Geological Society of America Abstracts with Program, 29, 6. Denver, 
Colorado: Geological Society of America. 
Wong, V. 1998. Gamma-Ray Characterization of Uranium-Series Nuclides and its Application to 
the Study of the Pea Blanca Natural Analog Site, Chihuahua, Mexico. Ph.D. Dissertation. El 
Paso, Texas: University of Texas.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment III-8 March 2000 
Wronkiewicz, D.; Bates, J.; Gerding, T.; Veleckis, E.; and Tani, B. 1992. Uranium Release and 
Secondary Phase Formation During Unsaturated Testing of UO2 at 90C. Journal of Nuclear 
Materials, 190, 107127. Amsterdam, Netherlands: Elsevier Science Publishers. 
Wronkiewicz, D.; Bates, J.; Wolf S.; and Buck, E. 1996. Ten-Year Results from Unsaturated 
Drip Tests with UO2 at 90C: Implications for the Corrosion of Spent Nuclear Fuel. Journal of 
Nuclear Materials, 238 (1), 7895. Amsterdam, Netherlands: Elsevier Science Publishers.

Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment IV-1 March 2000 
ATTACHMENT IV. 
DERIVATION OF FRACTURE CONTINUUM PROPERTIES 
Figures IV-1a and IV-1b present an x-y view of a fracture continuum and discrete fracture 
representation of a single node in the Box Canyon model, respectively. This example only 
considers the case of fractures oriented perpendicular to the y-direction. The permeability of the 
fracture continuum is calculated by equating the volumetric flow of water through the node to that 
calculated using discrete fracture representation due to a gradient in potential gradient, .h, 
applied perpendicular to the x-y plane. Let QC and QD be the volumetric flow rate of water in the 
fracture continuum and discrete fracture representations in the z-direction only: 
(Eq. IV.1) 
(Eq. IV.2) 
where nf is the number of fractures perpendicular to the y-direction within the node, b is the 
fracture aperture,  is the viscosity of water, kD and kC are the permeability of the discrete fracture 
and fracture continuum representations, respectively, where: 
(Eq. IV.3) 
(Eq. IV.4) 
Now, setting QC = QD yields: 
(Eq. IV.5) 
(Eq. IV.6) 
where D is the fracture spacing shown on Figure IV-1b 
h 
k 
x b n Q D 
f D . . = 
 
D
y 
n f 
. = 
12
2 b 
kD = 
h 
b 
x b 
D
y 
h k y x C . . . = . . . 
12
2 
D 
b 
kC 12
3 
= 
h 
k 
y x Q C 
C . . . = 


Title: Natural Analogs for the Unsaturated Zone U0135 
ANL-NBS-HS-000007 REV00 Attachment IV-2 March 2000 
An identical derivation follows by analogy for fractures oriented in the x-direction. 
To find the y scaling factor for this node with an observed water flow feature, set nf = 1 to 
condition the node to contain a single discrete fracture (note: D = .y for all nodes in the Box 
Canyon model). Once again, setting QC = QD: 
(Eq. IV.7) 
(Eq. IV.8) 
where k*
C is the permeability of the conditioned fracture continuum node. Therefore, the scaling 
factor between this node and the background unconditioned nodes is: 
(Eq. IV.9) 
The derivation of x follows by analogy. 
Figure IV-1. Plan view of node using a) fracture continuum and b) discrete fracture 
representations. 
h 
b 
x b h k y x C . . = . . . 
12
2 
* 
y 
b 
kC . 
= 
12 
3 
* 
y 
D 
D 
b 
y 
b 
k
k
C
C 
y . 
= . = = 
12 
12 
3
3 
* 
 
discrete fractures D 
.x 
.y 
b) a) 
.x 
.y 
z 
y
x

ATTACHMENT V 
SOFTWARE ROUTINES