1 Reactive transport modeling of the interaction ...

Reactive transport modeling of the interaction between water and a cementitious grout in a fractured rock. Application to ONKALO (Finland). Josep M. Solera*, Marja Vuoriob, Aimo Hautojärvib a

IDAEA-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain

b

POSIVA OY, Olkiluoto, FI-27160 Eurajoki, Finland

*Corresponding author. E-mail: [email protected], Ph.: +34 934095410, Fax: +34 934110012

Abstract Grouting of water-conducting fractures with low-alkali cement is foreseen for the potential future repository for spent nuclear fuel in Finland (ONKALO). A possible consequence of the interaction between groundwater and grout is the formation of highpH solutions which will be able to react with the host rock (gneisses) and alter its mineralogy and porosity. A reactive transport modeling study of this possible alteration has been conducted. First, the hydration of the low-alkali cementitious grout has been modeled, using results from the literature as a guide. The hydrated cement is characterized by the absence of portlandite and the presence of a C-S-H gel with a Ca/Si ratio about 0.8 after tens of years (Ca/Si is about 1.7 in Ordinary Portland Cement). Second, calculations have simulated the interaction between flowing water and grout and the formation of an alkalinity plume, which flows beyond the grouted section of the fracture. The calculations include the hydration and simultaneous leaching of the grout through diffusive exchange between the porewater in the grout and the flowing water in the fracture. The formation of an alkaline plume is extremely limited when the low-pH grout is used. Even when using a grout with a lower silica fume content, the extent and magnitude of the alkaline plume is rather minor. These results are in qualitative agreement with monitoring at ONKALO.

Keywords low-alkali cement, grout, fracture, flow, diffusion, porosity, alteration

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1. Introduction It is currently planned to use cement grout to seal conductive fractures at the ONKALO site in Finland (potential site for a deep geological repository for spent nuclear fuel). The interaction between groundwater and the grout may cause the formation and release of hyperalkaline solutions along these fractures, which can in turn react with the host rock and alter its mineralogy and porosity (e.g. Soler and Mäder 2007, 2010). The objective of this study was to use reactive transport calculations to study the leaching of the cement grout injected in the fractures and the release of alkalinity (high pH) into the flowing groundwater. The study is structured into 2 parts: (1) Modeling of the hydration of the low-alkalinity cement used for the grout (batchtype calculations). Recent developments regarding the thermodynamic modeling of the hydration of Portland cement (e.g. Lothenbach and Winnefeld, 2006) allow the explicit incorporation of this process into standard reactive transport codes. (2) Two-dimensional reactive transport calculations investigating the possible formation of a high-pH plume. In this novel modeling approach, the incorporation of a model for the hydration of the grout allows the simultaneous calculation of the hydration and leaching of the cementitious grout and the alteration of the host rock. Water flows around a grouted section of the fracture; diffusion from the grout causes the formation of the high-pH plume. This solution interacts with the host rock as it continues flowing through the fracture. 2. Description of the reactive transport code Reactive transport modeling was performed using CrunchFlow (Steefel, 2008). Details of the code can be found in the user’s manual (downloadable from www.csteefel.com). Only an outline will be given here. Crunchflow solves numerically the advection-dispersion-reaction equations

( (C mob j

C immob )) j t

where

D C mob j

qC mob j

Rj

(j=1,2,…,Ntot)

(1)

is porosity, C mob is the total concentration of mobile component or primary j

species j in solution, C immob is the total concentration of immobile component j in j solution (sorbed by surface complexation or ion exchange), D is the combined dispersion-diffusion coefficient, q is Darcy velocity, Rj is the total reaction rate affecting component j, t is time and Ntot is the total number of independent aqueous chemical components (primary species). The combined diffusion-dispersion coefficient D is defined as the sum of the mechanical or kinematic dispersion D* and the effective diffusion coefficient De D = D* + De

(2)

2

The kinematic dispersion coefficient is written as Dij*

T

qi q j

q

L

T

q

(3)

where L and T are the longitudinal and transverse dispersivities, respectively, and q is the magnitude of the Darcy velocity. The model assumes that the principal direction of flow is aligned with the grid, i.e., Dij* is a diagonal matrix. The total reaction rate for component j, Rj, is given by Rj

jm

(4)

Rm

m

where Rm is the rate of precipitation ( Rm > 0) or dissolution ( Rm < 0) of mineral m per unit volume of rock, and jm is the number of moles of j per mole of mineral m. Since mineral reactions are described using kinetic rate laws, initial mineral surface areas and several reaction rate parameters have to be supplied by the user as input. In this set of simulations, the reaction rate laws that have been used are of the form Rm

aini f m ( G )

k m a HnH

Am

terms

(5)

i

where R m is the reaction rate for a given mineral in units of mol/m3rock/s, Am is the mineral surface area (m2/m3rock), k m is the reaction rate constant (mol/m2/s) at the temperature of interest, a HnH is the term describing the effect of pH on the rate, a ini is a term describing a catalytic/inhibitory effect by another species on the rate, and f m ( G ) is the function describing the dependence of the rate on solution saturation state. The summation term indicates that several parallel rate laws may be used to describe the dependence of the rate on pH or on other species. The f m ( G ) function has the form m2

f m ( G)

1

IAP K eq

m1

(6)

where G is the Gibbs energy of the reaction (J/mol), R is the gas constant, T is temperature (K), IAP is the ionic activity product of the solution with respect to the mineral, and Keq is the equilibrium constant for that mineral reaction (ionic activity product at equilibrium). Changes in mineral surface area A (m2/m3bulk) due to reaction are calculated according to

3

2

A

A

initial

A

initial

m

initial m

3

(dissolution)

initial 2

A

2

3

(7)

3

(precipitation)

initial

(8)

The inclusion of a 2/3 dependence on porosity is chiefly to ensure that as the porosity goes to 0, so too does the mineral surface area available for reaction. This formulation is used primarily for primary minerals (that is, minerals with initial volume fractions > 0). For secondary minerals which precipitate, the value of the initial bulk surface area specified is used as long as precipitation occurs—if this phase later dissolves, the above formulation is used, but with an arbitrary “initial volume fraction” of 0.01. Regarding the treatment of solid solutions, a kinetic approach similar to the one proposed by Carey and Lichtner (2006, 2007) and Lichtner and Carey (2006) has been used. Given a binary solid solution with compositional end-members AC and BC, stoichiometric solids such as BC, A0.1 B0.9C, A0.2B0.8C, …, AC are defined. The dissolution reaction for each of these stoichiometric solids can be written as AxB1-xC

xA + (1-x) B + C

(9)

The equilibrium constant for this reaction will be defined as

K ss ( xss )

K1 1 xss

xss

K2

2

(1 xss )

1 xss

(10)

where K1 and K2 are the equilibrium constants for the dissolution reactions of endmembers AC and BC, respectively, xss is the mol fraction of AC and 1 and 2 are the activity coefficients of end-members AC and BC in the solid solution, respectively. Once defined in this manner, the reaction of each stoichiometric solid in a solid solution is treated just as any other phase (Eq. 5). For the sake of simplicity, only a few intermediate terms in the solid solution series have been taken into account. 3. Modeling of the hydration of the low-pH grout Modeling of the hydration of the low-pH grout at 25oC was performed using the same approach used previously in the modeling of the hydration of Ordinary Portland Cement using CrunchFlow (Gaus et al., 2010; Savage et al., 2011). This is a batch-type calculation (no solute transport, closed system) involving the dissolution of the unhydrated phases in the initial cement and the precipitation of hydration products. 3.1. Model parameters 3.1.1. Grout composition The chemical composition of the UF16 cement used to prepare the low-pH grout is given in Table 1 (Arenius et al., 2008). The composition of the mix used to prepare the low-pH grout is shown in Table 2 (Arenius et al., 2008), together with the composition of the so-called normal grout. The initial composition and porosity of the low-pH grout used in the model is given in Table 3. This composition and porosity were calculated

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from the chemical composition and water/dry matter ratio shown in Tables 1 and 2 and phase densities. P2O5, TiO2 and MnO were not taken into account for this calculation. MgO was included in the clinker phases (alite, belite, aluminate, ferrite) as a trace component. The readily soluble Na and K sulfates were included in the solution rather than in the solid (they dissolve immediately upon addition of water). The superplastisizer in the cement mix was not taken into account when calculating the volume fractions of the different phases. The potential secondary phases (hydration products) that were considered in the model were calcite, brucite, hydrotalcite-OH, portlandite, C-S-H (solid solution), ettringite (solid solution), tricarboaluminate, Camonocarbonate (solid solution), syngenite, monosulfate (solid solution), gibbsite and ferrihydrite. Incorporation of Al into C-S-H was not taken into account, due to the lack of proper thermodynamic data. 3.1.2. Solution composition The composition of the water used to prepare the grout is given in Table 4. This composition comes from analyses of the water used for preparing the grout. However, Na, K and SO4 concentrations correspond to the dissolution of the readily soluble sulfates in the cement. 3.1.3. Thermodynamic data 41 solid phases and 76 species in solution have been taken into account in the calculations. All the chemical equilibria in solution at 25oC (Appendix, Table A.1) were taken from the database included in CrunchFlow, which is based on the EQ3/6 database (Wolery et al., 1990). The equilibrium constants for all the mineral reactions are given in the appendix (Table A.2). All the solid equilibrium constants at 25oC were taken from Lothenbach et al. (2008), except for monocarbonate (Lothenbach and Winnefeld, 2006), C-S-H (Kulik and Kersten, 2001), calcite, anhydrite, brucite, portlandite, syngenite (CrunchFlow), ferrihydrite (minteq database in PHREEQC; Parkhurst and Appelo, 1999), and the clinker phases alite, belite, aluminate and ferrite (arbitrary large solubilities, not actually used by the model; irreversible kinetics). The C-S-H, ettringite, Ca-monocarbonate and monosulfate solid solutions have been introduced in the model as several discrete compositions (different mol fractions of the end-members; appendix, Table A.2), with solubilities calculated from the solid solution models. Activity coefficients were calculated using the extended Debye-Hückel formulation (bdot model), with parameters from the database in CrunchFlow. The activity of water in the calculations is equal to the mol fraction of H2O in the solution. 3.1.4. Reaction rates Table 5 shows the rate parameters used for the clinker phases (alite, belite, aluminate, ferrite) and amorphous silica. Simple irreversible rates (Rm = -Am km) were used for the clinker phases, instead of the more complicated rate functions reported in Lothenbach and Winnefeld (2006). The rate law for SiO2(am) was of the form (Bandstra et al., 2008)

Rm

Am k1a H0.3

k 2 a H0.4 f m ( G)

(11)

5

with m1=m2=1 (Eq. 6). In order to reproduce the decrease in rate with time, three different values of km were used for each phase. The values of km were adjusted to fit results published by Lothenbach and Wieland (2010) and Lothenbach and Matschei (2009) for the hydration of low-alkali cement. Arbitrary values of Am were used. For all the other phases (except SiO2(am)), rate laws were written according to Eq. 5 (one single rate law, no pH effect, m1=m2=1) with large reaction rate constants (km=10-3 to 10-5 mol/m2/s) and initial surface areas (Am = 1e4 m2/m3) to simulate local equilibrium with respect to those phases. 3.2. Results Figure 1 shows the calculated evolution of solid phases during the experiment. These results can be compared with those from Lothenbach and Wieland (2010; Fig. 2c). Out of the clinker phases, alite is the one showing the fastest hydration. Belite and ferrite react much more slowly. Anhydrite and aluminate are completely consumed after a few hours. On the other hand, amorphous silica (C-S-H 0.0 in the figure) dissolves more slowly and takes about 100 years to be completely consumed. Regarding the hydration products, C-S-H (Ca/Si≈1.7), portlandite and ettringite precipitate initially, like in an Ordinary Portland Cement (OPC). However, the gradual release of silica into solution from the dissolution of SiO2(am) causes the dissolution of portlandite and the transformation of the initial C-S-H gel into a C-S-H with a lower Ca/Si ratio. When the SiO2(am) is completely consumed, C-S-H has a Ca/Si ratio about 0.8. Ettringite is also consumed in the process. At the end, small quantities (< 1 vol%) of calcium sulfate, gibbsite, ferrihydrite and hydrotalcite are also predicted to precipitate. The change in porosity is relatively minor, from an initial 80.3% to 72.5% once the process is complete (t ≈ 100 a). Figures 2 and 3 show the evolution of solution composition (pH, total solute concentrations) and the consumption of water by the hydration of the grout. In early stages, Ca and S concentrations are controlled by equilibrium with respect to CaSO4 (anhydrite). The drop in Ca and S concentrations at t ≈ 1e-3 a corresponds to the point when the initial anhydrite is completely dissolved. Na, K and Cl concentrations in the model increase only due to the consumption of water by the hydration of the clinker phases. The rest of changes in solute concentrations are due to the different mineral reactions taking place. Especially relevant are the transformation of the initial C-S-H (Ca/Si≈1.7) into a C-S-H with Ca/Si=1.0 at t ≈ 0.1 a and the dissolution of Fecontaining ettringite shortly afterwards, responsible for the peaks in Al and Fe. The precipitation of Al-end member ettringite, gibbsite and ferrihydrite cause a reduction in those concentrations after the peak. The transformation of small amounts of calcite to Ca-monocarbonate and back to calcite is responsible for the peak in total CO3. The transformation of C-S-H (Ca/Si=1) into C-S-H (Ca/Si=0.8) and dissolution of ettringite at t ≈ 10 a also has a strong impact on solution composition. Notice that although this modeling was based on the results from Lothenbach and Wieland (2010), those results only extend up to 1000 d, while the current modeling

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extends up to 200 a. The long-term evolution of the grout is controlled by the dissolution kinetics of the silica fume. More detailed information about this kinetics could place better constraints on the precise timing and duration of the process. 4. Two-dimensional modeling of grout-rock interaction Using the grout hydration model presented in section 3, calculations were performed simulating the flow of water around a grouted section of a fracture (Fig. 4). The objective of these new calculations was to study the possible formation of a high-pH plume in this scenario. Figure 5 shows schematically the numerical representation and dimensions of the domain. The two-dimensional numerical domain is actually composed of two different domains. To the left of the thick vertical line in Fig. 5 the domain corresponds to the fracture plane. The open fracture is in the upper part and a grouted section of the fracture is below that. Flow in the open fracture is from left to right in the figure. Solute transport in the grout is only by diffusion. To the right of the line the two-dimensional domain corresponds to a section perpendicular to the fracture plane. The domain contains the open fracture and the rock below that. Only one half of the fracture opening (0.5 mm) is taken into account, due to symmetry. The width of the domain in the 3rd dimension (normal to the plot; parallel to the fracture plane) is assumed to be equal to 1 m. A no-flow boundary is imposed at the center of the fracture. Due to the fact that this boundary is located inside the numerical domain, it is imposed by defining an impermeable inert material over the fracture. A mixing zone (large dispersion) has been defined between the 2 domains. The goal is to homogenize the solution flowing in the grout domain (gradients are created due to diffusion from the grout) before flowing into the rock domain. Also, part of the solution flows out of the numerical domain at that point to avoid an excess of flow into the rock domain. The band of water flowing next to the grout in the model has a width equal to 0.5 m. This width was estimated from the residence time of water in the fracture in the grout domain and the diffusion coefficient in the water (1e-9 m2/s), which define a transport distance from the grout-water interface and into the open fracture. A second equivalent 0.5 m-wide band of water would flow on the opposite side of the grouted section of the fracture. All external boundaries are no-flow boundaries, except where water flows into or out of the domain at the fracture ends. At those points an advective-flux condition has been used. 4.1. Model parameters 4.1.1. Numerical discretization In the direction normal to flow in the fractures, the length of the numerical elements is 2.5e-4 m near the grout-water and rock-water interfaces, and it increases gradually up to 0.05 m in the water and 0.1 m in the grout and rock. In the direction parallel to flow in

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the fracture, the element size ranges between 0.02 m (rock-mixing zone interface) and 0.5 m. The total number of elements in the domain is about 1000. Computer calculation times (Intel® Xeon® CPU X5482 3.2GHz) are about 13 days for a simulation time of 50 years. 4.1.2. Grout and rock composition Two different grout compositions have been used in the calculations; low-pH and normal grout. The compositions are given in Table 3. The composition of the rock is shown in Table 6. This composition corresponds to the dominant rock type at ONKALO (migmatitic gneisses; Kärki and Paulamäki, 2006). Primary mineral surface areas were initially calculated assuming spherical grains and a grain radius equal to 1 mm (Kärki and Paulamäki, 2006). However, these areas have been decreased by a factor of 1000 to minimize the effect of rock reactivity caused by the initial porewater not being at equilibrium with those minerals (changes in porewater composition without interaction with fracture water). Notice that initial porewater composition is based on analyses of the groundwater in the fractures of the rock. Future work should make use of available porewater analyses (Eichinger et al., 2006, 2010) for a more accurate calculation of the evolution of rock composition. According to the conceptual model for the fractures at ONKALO (Posiva Oy, 2009b), porosity is 5% in a 1-cm-thick zone next to the fracture wall and 1% further into the rock. 4.1.3. Solution composition The composition of the initial porewater in the rock (Table 7) was estimated from data in Andersson et al. (2007) and Posiva Oy (2009a) for Olkiluoto groundwater at a depth between 350 and 470 m (saline Na-Ca-Cl water). These studies report the distribution of solute concentrations with depth. The composition of the water at a depth of about 400 m was taken from these measurements. Effectively zero concentrations (1e-9 mol/kg_H2O) were assumed for Al and Mg, to avoid supersaturation with respect to secondary minerals (zeolites). The resulting solution is at equilibrium with respect to calcite, quartz and pyrite and undersaturated with respect to the other primary minerals in the host rock. This solution is also the water flowing through the fracture in the calculations. Unlike in section 3, H2O mass balance (consumption of water) is not included in the calculations, i.e., the activity of water is always equal to 1. On one hand, given enough time, the lack of equilibrium between the initial rock porewater and the minerals in the rock, together with the small porosities, cause a large consumption of water in the rock pores and a dramatic increase in salinity if consumption of water is taken into account. On the other hand, this is now an open system, with a continuous supply of water through the fractures, which justifies not including the H2O mass balance. 4.1.4. Thermodynamic data 71 solid phases and 75 species in solution have been taken into account in the calculations. All the chemical equilibria in solution at 25oC (appendix, Table A.1) were taken from the database included in CrunchFlow, which is based on the EQ3/6 database

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(Wolery et al., 1990). The equilibrium constants for the cement phases and the minerals in the rock at 25oC are given in the appendix (Tables A.2, A.3). The values of the equilibrium constants for all the mineral reactions in the rock are from the database included in CrunchFlow, except for plagioclase An29Ab71 (Stefánsson, 2001). The log Keq value for biotite Ann55Phl45 has been calculated assuming an ideal solid solution between the Fe (annite) and Mg (phlogopite) end members. Activity coefficients were calculated using the extended Debye-Hückel formulation (bdot model), with parameters from the database in CrunchFlow. The activity of water is equal to 1. 4.1.5. Reaction rates Rate laws for the clinker phases are the same as those used in section 3 (Table 5). Reaction rates at 25oC for primary minerals in the rock are based on literature results (Bandstra et al., 2008; Palandri and Kharaka, 2004; Burch et al., 1993; Soler et al., 1996). The rate laws are given in Table 8. Fast kinetics has been assumed for the secondary minerals, resembling local equilibrium for those phases. 4.1.6. Flow and transport parameters Darcy velocity in the fracture is equal to 32 m3/m2/a. This value was calculated from volumetric flow information provided by Posiva. The rationale behind this value is that in a 1 m wide section of a fracture, with an opening equal to 1 mm, a transmissivity equal to 1e-7 m2/s, and subject to a hydraulic gradient of 1%, the resulting volumetric flow will be 32 L/a, which is equivalent to 32 m3/m2/a. Such a fracture would be typically grouted to limit groundwater flow into open excavations. The diffusion coefficient De in the open fracture is equal to 1e-9 m2/s. No dispersion is taken into account (open fracture). Diffusion is the only solute transport mechanism inside the rock and the grout. The effective diffusion coefficient for all the species in the rock is calculated making use of Archie’s Law (De = mD0) with a cementation exponent m equal to 2 and D0 = 1e-9 m2/s. The initial De value in the bulk rock ( = 0.01) is 1e-13 m2/s, which is in agreement with measured values for Cl- (Eichinger et al., 2010). The effective diffusion coefficient for all the species in the grout is calculated using the expression De

D0

(12)

with the tortuosity factor τ = 0.0125 and D0 = 1e-9 m2/s. Using Eq. 12 the initial effective diffusion coefficient in the grout is set to a value De = 1e-11 m2/s, which is based on experimental data from Posiva (De for different grouts in the 2e-11 – 8e-11 m2/s range; Vuorinen et al., 2005). 4.2. Results Figures 6 to 9 show the evolution of pH in the two-dimensional domain with time. Two different cases are shown. Results corresponding to the normal-pH grout are shown on 9

the left-hand-side in the figures; results corresponding to the low-pH grout are shown on the right-hand-side. Notice that the plots correspond to the numerical domain shown in Fig. 5 but rotated 90o counterclockwise (flow is from bottom to top). The color scale is the same in all the plots. At very early times (Fig. 6) the distribution of pH is practically identical in the two systems, with pH about 12.4 - 12.5 in the grout and the background pH value of 8 in the rest of the system. However, very quickly a difference is established between the 2 cases, with lower pH values in the grout for the low-pH grout system. A clear pH gradient is created by diffusion from the grout to the water in the fracture, with higher pH close to the grout-water interface. However, pH values in the open fracture are never very large. Figure 10 shows pH at different times along a line just over the grout-water interface and extending into the mixing zone and further (dashed lines in Fig. 9). At a given time, one can see high pH values along the grout-water interface and a sudden pH drop in the mixing zone, caused by the homogenization of the solution before flowing into the rock fracture. pH values decrease gradually with time in the normal-pH system. However, this decrease in pH is more pronounced at early times in the low-pH system. The higher pH values in the grout for the normal-pH case are explained by the composition of the grout and the evolution of porosity at the grout-water interface. The normal-pH grout has a lower silica fume content, which favors the presence of a C-S-H gel with a higher Ca/Si ratio, resulting in a higher pH in the grout. Also, there is a strong sealing of porosity at the grout-water interface in the normal-pH case (Fig. 11), due to the precipitation of secondary ettringite and calcite (Fig. 12). Calcite precipitates on the fracture side of the interface (fracture water is already at equilibrium with respect to calcite) and ettringite on the rock side (notice the two zero-porosity points in Fig. 11a). This sealing effect (secondary calcite, Fig. 12) is less important in the low-pH case. The strong sealing in the normal-pH case causes a slower diffusive exchange between the grout and the open fracture. Notice also the different composition (Ca/Si ratio) of the CS-H gel in the two different cases. There is also sealing of porosity at the rock-fracture interface due to the precipitation of secondary calcite, but this sealing is limited to a few cm from the mixing zone after 50 years (Fig. 13). There is also minor precipitation of zeolites (stilbite, mesolite) and saponite. pH values have been monitored since 2005 in two boreholes intersecting grouted fractures at ONKALO (ONK-KR3, ONK-KR4; Rautio, 2005; Reiman et al., 2006). Water was sampled very close to grouted sections of fractures. These boreholes are at a much shallower depth than the ca. 400 m assumed for the repository, and the composition of the groundwater is different (less saline) from that used in the calculations reported here. At any rate, and for the sake of comparison, the results of monitoring of pH have been compared to the results from the calculations. Figure 14 shows the measured data and the modeling results. Given that the water was sampled very close to the grout, but the exact distance is difficult to assess, the comparison has been made with the composition of the water in the mixing zone (water flowing out of the grouted section and into the rock domain). Despite the fact the groundwater

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composition at the shallower depth is different from that at repository depth, and that the calculations were performed with generic parameters not intending to simulate exactly the flow and transport parameters, geometries and dimensions for the two monitoring boreholes, the similarity between the calculated and measured pH is rather remarkable. This similarity suggests that the main processes responsible for the evolution of pH are being captured. 5. Summary and conclusions In a first step, the hydration of the low-pH grout was modeled (batch type, closed system calculation). Previous results in the literature were used as a guide. The hydration process is controlled by the dissolution rates of the clinker phases (alite, belite, aluminate, ferrite) and the silica fume in the grout mix. Unlike in an Ordinary Portland Cement, the supply of silica by the dissolution of the silica fume causes the formation of C-S-H gel with a Ca/Si ratio about 0.8 once the process is completed. Portlandite only precipitates at early stages but is quickly consumed. The hydration process, under the conditions and parameters used in the model, takes about 100 years to complete. The dissolution rate of the silica fume is what controls the long term evolution of the process. In a second stage, a relevant scenario for the potential formation of a high-pH plume was simulated. In this scenario water flows around a grouted section of a fracture. In a novel modeling approach, the grout is simultaneously hydrating and leaching and releasing alkalinity and solutes into the flowing water. Two different cases have been considered, based on the use of the reference low-pH grout or the so-called normal-pH grout, which has a lower silica fume content. The pH inside the grout decreases very quickly in the case of the low-pH grout. The higher pH values for the normal-pH grout are explained by the composition of the grout and the sealing of porosity at the grout-water interface. The pH of the flowing groundwater is never very high (except for the very initial stages) even for the normal-pH case. The modeling results compare reasonably well with pH monitoring data from two boreholes intersecting grouted sections of fractures, even though the groundwater composition at the shallower depth of the boreholes is different from that at repository depth. Also, the calculations were performed with generic parameters not intended to simulate exactly the flow and transport parameters, geometries and dimensions for the two monitoring boreholes. These results suggest that the main processes responsible for the evolution of pH are being captured. The main conclusion from the study is that the formation of an alkaline plume is extremely limited when the low-pH grout is used. And even when using a grout with a lower silica fume content, the extent and magnitude of the alkaline plume are rather minor. Acknowledgements The financial support from Posiva and the comments from two anonymous reviewers are gratefully acknowledged.

11

References Andersson, J., Ahokas, H., Hudson, J.A., Koskinen, L., Luukkonen, A., Löfman, J., Keto, V., Pitkänen, P., Mattila, J., Ikonen, A.T.K., Ylä-Mella, M., 2007. Olkiluoto Site Description 2006. Posiva Report 2007-03, Posiva Oy, Olkiluoto. Arenius, M., Hansen, J., Juhola, P., Karttunen, P., Koskinen, K., Lehtinen, A., Lyytinen, T., Mattila, J., Partamies, S., Pitkänen, P., Raivio, P., Sievänen, U., Vuorinen, U., Vuorio, M., 2008. R20 Summary Report: The Groundwater Inflow Management in ONKALO – The Future Strategy. Posiva Working Report 2008-44, Posiva Oy, Olkiluoto. Bandstra, J.Z., Buss, H.L., Campen, R.K., Liermann, L.J., Moore, J., Hausrath, E.M., Navarre-Sitchler, A.K., Jang, J.-H., Brantley, S.L., 2008. Appendix: Compilation of mineral dissolution rates, in: Brantley, S.L., Kubicki, J.D., White, A.F. (Eds.), Kinetics of Water-Rock Interaction. Springer, New York, pp. 737-823. Burch, T.E., Nagy, K.L., Lasaga, A.C., 1993. Free energy dependence of albite dissolution kinetics at 80oC and pH 8.8. Chem. Geol. 105, 137-162. Carey, J.W., Lichtner, P.C, 2006. Calcium Silicate Hydrate Solid Solution Model Applied to Cement Degradation using the Continuum Reactive Transport Model FLOTRAN. Report LA-UR-06-0636, Los Alamos National Laboratory, Los Alamos. Carey, J.W., Lichtner, P.C., 2007. Calcium silicate hydrate (C-S-H) solid solution model applied to cement degradation using the continuum reactive transport model FLOTRAN, in: Mobasher, B., Skalny, J. (Eds.), Transport Properties and Concrete Quality: Materials Science of Concrete, Special Volume, pp. 73-106. American Ceramic Society. Eichinger, F., Hämmerli, J., Waber, H.N., Diamond, L.W., Smellie, J.A.T., 2010. Characterisation of Matrix Pore Water and Fluid Inclusions in Olkiluoto Bedrock from Drilling OL-KR47. Posiva Working Report 2010-58, Posiva Oy, Olkiluoto. Eichinger, F.L., Waber, H.N., Smellie, J.A.T., 2006. Characterisation of Matrix Pore Water at the Olkiluoto Investigation Site, Finland. Posiva Working Report 2006-103, Posiva Oy, Olkiluoto. Elkem, 2005. GroutAid®, Safety Data Sheet, 508/GBR, Rev. 09, March 01, 2005 (www.elkem.com/dav/1f833551d6.pdf, 17.11.2010). Gaus, I., Rueedi, J., Blaser, P. (Eds.), 2010. LCS – Comparative Modelling of Cement Experiments. Nagra Arbeitsbericht NAB 10-07. Nagra, Wettingen. Kärki, A., Paulamäki S., 2006. Petrology of Olkiluoto. Posiva Report 2006-02, Posiva Oy, Olkiluoto. Kulik, D.A., Kersten, M., 2001. Aqueous solubility diagrams for cementitious waste stabilization systems: II, end-member stoichiometries of ideal calcium silicate hydrate solid solutions. J. Am. Ceram. Soc. 84, 3017-3026.

12

Lichtner, P.C., Carey, J.W., 2006. Incorporating solid solutions in reactive transport equations using a kinetic discrete-composition approach. Geochim. Cosmochim. Acta 70, 1356-1378. Lothenbach, B., Matschei, T., 2009. Thermodynamic modeling; hydration modeling, in: The Fred Glasser Cement Science Symposium, 17-19 June 2009, Aberdeen, UK (www.abdn.ac.uk/chemistry/cement-symposium/presentations/, 17.11.2010). Lothenbach, B., Matschei, T., Moschner, G., Glasser, F.P., 2008. Thermodynamic modelling of the effect of temperature on the hydration and porosity of Portland cement. Cem. Concr. Res. 38, 1-18. Lothenbach, B., Wieland, E. (2010) Chemical evolution of cementitious materials, in: Cementititous Materials in Safety Cases for Geological Repositories for Radioactive Waste Management: Role, Evolution and Interactions. NEA Workshop, 17-20 November 2009, Brussels. Report NEA/RWM/IGSC(2010)5, OECD, Brussels. Lothenbach, B., Winnefeld, F., 2006. Thermodynamic modelling of the hydration of Portland cement. Cem. Concr. Res. 36, 209-226. Palandri, J.L., Kharaka, Y.K., 2004. A Compilation of Rate Parameters of WaterMineral Interaction Kinetics for Application to Geochemical Modeling. Open File Report 2004-1068, U.S. Geological Survey, Menlo Park. Parkhurst, D.L., Appelo, C.A.J., 1999. User’s Guide to Phreeqc (Version 2) – A Computer Program for Speciation, Batch-Reaction, One-Dimensional Transport, and Inverse Geochemical Calculations. Water Resources Investigations Report 99-4259, U.S. Geological Survey, Denver. Posiva Oy, 2009a. Olkiluoto Site Description 2008, Part 1. Posiva Report 2009-01, Posiva Oy, Olkiluoto. Posiva Oy, 2009b. Olkiluoto Site Description 2008, Part 2. Posiva Report 2009-01, Posiva Oy, Olkiluoto. Rautio, T., 2005. Core Drilling of Boreholes ONK-KR1, ONK-KR2, ONK-KR3, ONKKR4 and ONK-PVA1 in ONKALO at Olkiluoto 2005. Posiva Working Report 2005-66, Posiva Oy, Olkiluoto. Reiman, M., Pöllänen, J., Väisäsvaara, J., 2006. Flow Measurements in ONKALO at Olkiluoto. Probe Holes and ONK-KR1 – ONK-KR4, ONK-PVA1 and ONK-YPPL18. Posiva Working Report 2006-65, Posiva Oy, Olkiluoto. Rochelle, C.A., Noy, D.J., 2000. GTS/HPF: Mineral Reaction Kinetics under Alkaline Conditions – Review of Literature for Selected Materials. Nagra Internal Report NIB 00-28 (unpublished), Nagra, Wettingen. Savage, D., Soler, J.M., Yamaguchi, K., Walker, C., Honda, A., Inagaki, M., Watson, C., Wilson, J., Benbow, S., Gaus, I., Rueedi, J., 2011. A comparative study of the

13

modelling of cement hydration and cement-rock laboratory experiments. Appl. Geochem. (submitted). Soler, J.M., Lasaga, A.C., 1996. A mass transfer model of bauxite formation. Geochim. Cosmochim. Acta 24, 4913-4931. Soler, J.M., Mäder, U.K., 2007. Mineralogical alteration and associated permeability changes induced by a high-pH plume: Modeling of a granite core infiltration experiment. Appl. Geochem. 22, 17-29. Soler J.M., Mäder, U.K., 2010. Cement-rock interaction: Infiltration of a high-pH solution into a fractured granite core. Geol. Acta 8, 221-233. Soler, J.M., Pfingsten, W., Paris, B., Mäder, U.K., Frieg, B., Neall, F., Källvenius, G., Yui, M., Yoshida, P., Shi, P., Rochelle, C.A., Noy, D.J., 2006. Grimsel Test Site – Investigation Phase V. HPF-Experiment: Modelling Report. Nagra Technical Report NTB 05-01, Nagra, Wettingen. Steefel, C.I., 2008. CrunchFlow. Software for Modeling Multicomponent Reactive Flow and Transport. User’s Manual. Lawrence Berkeley National Laboratory, Berkeley. Stefánsson, A., 2001. Dissolution of primary minerals of basalt in natural waters. I. Calculation of mineral solubilities from 0oC to 350oC. Chem. Geol. 172, 225-250. Vuorinen, U., Lehikoinen, J., Imoto, H., Yamamoto, T., Alonso, M.C., 2005. Injection Grout for Deep Repositories. Subproject 1: Low-pH Cementitious Grout for Larger Fractures, Leach Testing of Grout Mixes and Evaluation of the Long-Term Safety. Posiva Working Report 2004-46, Posiva Oy, Olkiluoto. Wolery, T. J., Jackson, K.J., Bourcier, W.L., Bruton, C.J., Viani, B.E., Knauss, K.G., Delany, J.M., 1990. Current status of the EQ3/6 software package for geochemical modeling, in: Melchior, C., Bassett, R.L. (Eds.), Chemical Modeling of Aqueous Systems II. ACS Symposium Series No 416, pp. 104-116.

14

Fig. 1. Calculated evolution of solid phase content vs. time. (a) Unhydrated cement phases. (b) Hydration products. (c) Results from Lothenbach and Wieland (2010, OECD), for comparison. Notice that time goes up only to 1000 days in this last plot. Fig. 2. Calculated evolution of (a) pH, and (b) Ca, S and Si concentrations vs. time. Fig. 3. Calculated evolution of Na, K, Mg, CO3, Fe, Al, Cl and H2O concentrations vs. time. The last plot (H2O) shows the consumption of water due to the hydration of the cement (precipitation of hydrated phases). Fig. 4. Diagram showing the concept behind the calculations. Water flows around a grouted section of a fracture. There is diffusive transport of solutes between the grout and the flowing water. Fig. 5. Schematic representation of the numerical domain. Fig. 6. pH in the two-dimensional domains at t = 1.14e-4 a. Dimensions are in m. Fig. 7. pH in the two-dimensional domains at t = 0.114 a. Dimensions are in m. Fig. 8. pH in the two-dimensional domains at t = 0.913 a. Dimensions are in m. Fig. 9. pH in the two-dimensional domains at t = 30 a. Dimensions are in m. Fig. 10. pH vs. distance along a line just over the grout-water interface and extending into the mixing zone and the rock fracture. The upper plot corresponds to the normal-pH case and the lower plot to the low-pH case. Fig. 11. Porosity distribution across the water-grout interface (perpendicular to the direction of flow) at t = 50 a. Interface is at x = 0.5 m. Open fracture is to the left of the interface. (a,c,e) Normal-pH case; (b,d,f) low-pH case. (a,b) Near the fracture inlet; (c,d) midway between fracture inlet and mixing zone; (e,f) near the mixing zone. Fig. 12. Secondary mineral content (vol%) vs. distance normal to the direction of flow at t = 50 a. Water-grout interface is at x = 0.5 m. Open fracture is to the left of the interface. (a,c,e) Normal-pH case; (b,d,f) low-pH case. (a,b) Near the fracture inlet; (c,d) midway between fracture inlet and mixing zone; (e,f) near the mixing zone. Fig. 13. Porosity and secondary mineral content (vol%) vs. distance normal to the direction of flow at t = 50 a. Fracture-rock interface is at x = 0.5 m. Open fracture is to the left of the interface. (a,c,e) Porosity; (b,d,f) secondary minerals. (a,b) 1 cm downflow of the mixing zone; (c,d) 25 cm downflow of the mixing zone; (e,f) 35 cm downflow of the mixing zone. Fig. 14. pH vs. time. (upper) Borehole ONK-KR3, low-pH grout; (lower) borehole ONK-KR4, normal-pH grout. Symbols correspond to measurements and lines to model results.

14.0 13.0

pH

12.0 11.0 10.0 9.0 8.0 1.0E-05

1.0E-03

1.0E-01

1.0E+01

1.0E+03

1.0E+01

1.0E+03

t (a)

8.0E-02

Ca S

C (mol/L)

6.0E-02

Si 4.0E-02 2.0E-02 0.0E+00 1.0E-05

1.0E-03

1.0E-01 t (a)

8.5E-02

2.3E-02

8.0E-02

K (mol/L)

Na (mol/L)

2.5E-02

2.1E-02 1.9E-02

1.7E-02

7.0E-02 6.5E-02

1.5E-02 1.0E-05

7.5E-02

6.0E-02 1.0E-03

1.0E-01

1.0E+01

1.0E+03

1.0E-05

1.0E-03

t (a)

1.0E-01

1.0E+01

1.0E+03

1.0E+01

1.0E+03

1.0E+01

1.0E+03

1.0E+01

1.0E+03

t (a)

2.5E-03

3.0E-04

CO3 (mol/L)

Mg (mol/L)

2.0E-03 1.5E-03 1.0E-03

2.0E-04

1.0E-04

5.0E-04

0.0E+00

0.0E+00 1.0E-05

1.0E-03

1.0E-01

1.0E+01

1.0E-05

1.0E+03

1.0E-03

t (a)

1.0E-04

2.0E-03

8.0E-05

1.6E-03

Al (mol/L)

Fe (mol/L)

t (a)

6.0E-05

4.0E-05

1.2E-03 8.0E-04

4.0E-04

2.0E-05

0.0E+00

0.0E+00 1.0E-05

1.0E-03

1.0E-01

1.0E+01

1.0E-05

1.0E+03

1.0E-03

6.0E+01 H2O (mol/kg_H2O_init)

4.0E-04 3.5E-04

Cl (mol/L)

1.0E-01 t (a)

t (a)

3.0E-04 2.5E-04 2.0E-04 1.0E-05

1.0E-01

5.5E+01 5.0E+01 4.5E+01 4.0E+01

1.0E-03

1.0E-01 t (a)

1.0E+01

1.0E+03

1.0E-05

1.0E-03

1.0E-01 t (a)

Open fracture

Grout

FRACTURE PLANE

Q1, q1 0.5 m

NORMAL TO FRACTURE PLANE

INERT Mixing Q2, q2

GROUT

INERT

5m

ROCK

0.5 mm 0.5 m

2m Calculation domain

Q1

32 L / a

q1

32

L 1m3 1 a 1000 L 1m 10 3 m

32 m3 / m 2 / a

Q2

32 L / a

q2

32

L 1m3 1 a 1000 L 1m 10 3 m

32 m3 / m 2 / a

OPEN FRACTURE

OPEN FRACTURE

7.0

7.0 ROCK

6.0 5.0

MIXING ZONE

12.6

6.0

11.8

5.0

ROCK 12.6 11.8

MIXING ZONE

11.0

4.0

11.0

4.0 10.2

3.0

9.4

OPEN FRACTURE

10.2

3.0

GROUT 8.6

2.0

9.4

OPEN FRACTURE

GROUT 8.6

2.0

7.8

1.0

7.8

1.0 0.1

0.3

0.5

0.7

0.9

0.1

normal

0.3

0.5

0.7

0.9

low pH

Figure 6

7.0

7.0

6.0

6.0 12.6

5.0

11.8

5.0

4.0

11.0

4.0

11.8 11.0 10.2

10.2

3.0

9.4 8.6

2.0

3.0

9.4

2.0

8.6

7.8

1.0

7.8

1.0 0.1

0.3

0.5

0.7

0.9

0.1

normal

0.3

0.5

0.7

0.9

low pH

Figure 7

7.0

7.0

6.0

6.0 12.6

5.0

11.8 11.0

4.0

11.0

5.0

10.2

4.0

10.2

3.0

9.4 8.6

2.0

9.4

3.0

8.6

2.0

7.8

1.0

7.8

1.0 0.1

0.3

0.5

0.7

0.9

0.1

normal

0.3

0.5

0.7

0.9

low pH

Figure 8

7.0

7.0

6.0

6.0 9.2

12.5

5.0

11.5 10.5

4.0

5.0

8.8

4.0

8.4 8.0

9.5

3.0

8.5 7.5

2.0

3.0

7.6 7.2

2.0

6.5

6.8

1.0

1.0 0.1

0.3

0.5

0.7

0.9

0.1

normal

0.3

0.5

0.7

0.9

low pH

Figure 9

mixing

13

t=0.114 a

12

t=0.457 a t=0.913 a

11

t=2 a

pH

t=5 a t=10 a

10

t=20 a t=30 a t=40 a

9

normal

8 0

1

t=50 a

2

3

4

5

6

7

y (m)

mixing

13

t=0.114 a

12

t=0.457 a t=0.913 a

11

t=2 a

pH

t=5 a t=10 a

10

t=20 a t=30 a t=40 a

9

t=50 a

low pH

8 0

1

2

3

4 y (m)

Figure 10

5

6

7

Near the fracture inlet (b) Low pH, y = 0.25 m

100

100

80

80

Porosity (%)

Porosity (%)

(a) Normal pH, y = 0.25 m

60 40 20

60 40 20

0 0.47

0.48

0.49

0.50

0.51

0.52

0 0.47

0.53

0.48

0.49

x (m)

0.50

0.51

0.52

0.53

0.52

0.53

0.52

0.53

x (m)

Midway between fracture inlet and mixing zone (d) Low pH, y = 2.25 m

100

100

80

80

Porosity (%)

Porosity (%)

(c) Normal pH, y = 2.25 m

60 40 20

60 40 20

0 0.47

0.48

0.49

0.50

0.51

0.52

0 0.47

0.53

0.48

0.49

x (m)

0.50

0.51

x (m)

100

100

80

80

Porosity (%)

Porosity (%)

Near the mixing zone (e) Normal pH, y = 4.75 m (f) Low pH, y = 4.75 m

60 40 20 0 0.47

60 40 20

0.48

0.49

0.50

0.51

0.52

0.53

x (m)

0 0.47

0.48

0.49

0.50 x (m)

Figure 11

0.51

Near the fracture inlet (a) Normal pH, y = 0.25 m

(b) Low pH, y = 0.25 m 100

100

Calcite

60

Vol%

80

Ettring-Al10 CSH-10

40

CSH-14

CSH-12

20

40

0.500

0.505

CSH-08

20

Monosulf-Al02

0 0.495

Calcite

60

Vol%

80

Hydrotalcite 0 0.495

0.510

0.500

0.505

0.510

x (m)

x (m)

Midway between fracture inlet and mixing zone (c) Normal pH, y = 2.25 m 70

70

Ettring-Al10

60

60

CSH-10

40

Calcite

30

50

CSH-14

CSH-12

Vol%

50

Vol%

(d) Low pH, y = 2.25 m

20

40 30

Calcite

CSH-08

20

Monosulf-Al02

10 0 0.495

0.500

0.505

10 0 0.495

0.510

Hydrotalcite 0.500

x (m)

0.505

0.510

x (m)

Near the mixing zone (e) Normal pH, y = 4.75 m (f) Low pH, y = 4.75 m 60

Vol%

50 40

50

CSH-14

Calcite

40 30

CSH-08

Calcite

20

Monosulf-Al02

10 0 0.495

60

CSH-12

30 20

70

Ettring-Al10 CSH-10 Vol%

70

0.500

0.505

10

0.510

0 0.495

Hydrotalcite 0.500

0.505 x (m)

x (m)

Figure 12

0.510

1 cm after mixing zone (y = 5.41 cm) (b) Secondary minerals 5.0

8

4.0

6

3.0

Vol%

Porosity (%)

(a) Porosity 10

4

Calcite

2.0

2

1.0

0 0.4995

0.0 0.4950

Stilbite 0.5000

0.5005

0.5010

0.5050

x (m)

Mesolite 0.5150

x (m)

25 cm after mixing zone (y = 5.65 cm) (c) Porosity

(d) Secondary minerals 0.8

10

Calcite 0.6

6

Vol%

Porosity (%)

8

4

0.4

Stilbite

0.2

2 0 0.4995

0.5000

0.5005

0.0 0.4950

0.5010

Saponite-Ca 0.5050

Mesolite 0.5150

x (m)

x (m)

35 cm after mixing zone (y = 5.75 cm) (e) Porosity

(f) Secondary minerals 0.8

10

0.6

6

Vol%

Porosity (%)

8

4

0.2

2 0 0.4995

0.4

0.5000

0.5005

0.5010

0.0 0.4950

x (m)

Stilbite Saponite-Ca 0.5050 x (m)

Figure 13

Mesolite 0.5150

11.6

ONK-KR3 low pH

11.2 10.8

pH

10.4 10.0 9.6 9.2 8.8 8.4 0.0

0.5

1.0

1.5

2.0

2.5

t (a) 12.5

ONK-KR4 normal

12.0 11.5

pH

11.0 10.5 10.0 9.5 9.0 8.5 0.0

0.5

1.0

1.5 t (a)

Figure 14

2.0

2.5

Table 1 Chemical composition (wt%) of the UF16 cement (Arenius et al., 2008) SiO2

Al2O3

CaO

MgO

Na2O

K2O

P 2 O5

Fe2O3

TiO2

MnO

SO3

22.9

3.67

65.6

0.79

0.08

0.43

0.11

4.41

0.25

0.23

1.77

Table 2 Chemical composition of the low-pH (UF-41-14-4) and normal (UF-15-08-2.8) grouts (Arenius et al., 2008). DM: Dry matter. W: Water. SPL: Superplastisizer. Sample

Nomenclature

UF16 cement ( % of DM)

P308B

UF-41-14-4

59

Silica fume (% of DM) 41

5/5A

UF-15-08-2.8

85

15

W/DM 1.4 0.8

SPL (% of DM) 4 2.8

Table 3 Composition (vol%) of the low-pH (UF-41-14-4) and normal (UF-15-08-2.8) grouts

UF-41-14-4

Alite C3S 6.9

Belite C2S 1.9

Aluminate C3A 0.3

Ferrite C4AF 1.2

UF-15-08-2.8

15.4

4.2

0.6

2.8

Anhydrite

SiO2(am)

Porosity

0.3

9.1

80.3

0.6

5.1

71.3

Table 4 Composition of the water used to prepare the grout, in terms of total concentrations (mol/kg_H2O) and pH. Na, K and SO4 concentrations are calculated from the sulfate content of the cement, which dissolves very quickly into the water Ca

3.2e-4

Mg

2.4e-4

Na

1.9e-2 (from sulfates in cement)

K

6.6e-2 (from sulfates in cement)

CO3

4.2e-4 (equilibrium with atmosphere)

Al

1.0e-9

Fe(III)

2.5e-7

SiO2

2.0e-6

SO4

4.2e-2 (from sulfates in cement)

Cl

3.1e-4

pH

7.7 (charge balance) 2.6e-4 (equilibrium with atmosphere, Eh = 806 mV)

O2(aq)

Table 5 Fitted rate constants (log k, mol/m2/s) for the clinker phases and amorphous silica (silica fume) in the cement. Two values (log k1, log k2) are given for SiO2(am). Initial surface areas Am were 1e4 m2/m3 and 5e6 m2/m3 for the clinker phases and SiO2(am), respectively. The Am value for SiO2(am) was calculated from the specific surface (15 30 m2/g) reported in the specifications of the product (Elkem, 2005) and its density and volumetric content in the grout mix. Time

Alite

Belite

Aluminate

Ferrite

SiO2(am)

0 – 20 h

-5.5

-6.5

-6.5

-10.0

-11.4, -14.9

20 – 1000 h

-7.5

-8.5

-8.5

-10.0

-11.4, -14.9

1000 h – 200 a

-9.5

-10.5

-10.5

-10.0

-12.4, -15.9

Table 6 Mineralogical composition (vol%) and surface areas (m2/m3), for the zones with porosity equal to 5% (up to 1 cm from fracture walls) and 1% (further into the rock). Vol%

Am (m2/m3)

Vol%

Am (m2/m3)

Quartz

31.6

95.0

30.5

91.0

Plag. (An29Ab71)

17.8

53.0

17.1

51.0

9.0

27.0

8.6

26.0

23.8

71.0

22.8

68.0

Muscovite

8.0

24.0

7.6

23.0

Clinochlore

2.7

8.2

2.6

7.8

Cordierite

4.2

13.0

4.0

12.0

Sillimanite

1.9

5.7

1.8

5.4

Porosity

1.0

------

5.0

-----

MINERAL

Microcline Biotite (Ann55Phl45)

Table 7 Composition of the initial porewater in the rock, in terms of total concentrations (mol/kg_H2O), pH and Eh. Ca

3.5e-2

Mg

1.0e-9

Na

1.1e-1

K

2.6e-4

CO3

1.1e-4 (calcite equilibrium)

Al

1.0e-9

Fe

1.8e-6

SiO2

1.0e-4 (quartz equilibrium)

SO4

4.0e-4

Cl

1.8e-1 (charge balance)

pH

8.0

Eh

-206 mV (pyrite equilibrium)

Table 8 Rate parameters for the primary minerals in the rock. MINERAL

log k (mol/m2/s)

a HnH , a ini terms m1 0.3 H 0.4 H 0.457 H

Quartz

-11.4

a

Quartz

-14.9

a

Plagioclase

-9.67

a

Plagioclase

-11.84

----0.572 H

m2

References

1.0

1.0

(1)

1.0

1.0

(1)

14.0

0.4

(2, 3&4 for fm( G))

14.0

0.4

(2, 3&4 for fm( G))

14.0

0.4

(2, 3&4 for fm( G)), albite pH effect

Plagioclase

-14.88

a

Microcline

-10.06

a H0.50

14.0

0.4

(2, 3&4 for fm( G))

Microcline

-12.41

-----

14.0

0.4

(2, 3&4 for fm( G))

14.0

0.4

(2, 3&4 for fm( G))

0.823 OH

Microcline

-9.68

a

Biotite

-9.84

a H0.525

1.0

1.0

(2)

Biotite

-12.55

-----

1.0

1.0

(2)

Biotite

-13.30

a H0.2

1.0

1.0

(5)

Muscovite

-11.85

a

0.37 H

1.0

1.0

(2)

Muscovite

-13.55

-----

1.0

1.0

(2)

1.0

1.0

(2)

1.0

1.0

(5)

1.0

1.0

(2)

0.22 H 0.2 H 1.0 H

Muscovite

-14.55

a

Clinochlore

-14.6

a

Cordierite

-3.80

a

Cordierite

-11.20

-----

1.0

1.0

(2)

Cordierite

-16.0

a H0.5

1.0

1.0

Analogy to Al-silicates

1.0

1.0

Same as kyanite (2)

1.0

1.0

Same as kyanite (2)

1.0

1.0

Analogy to Al-silicates

1.268 H

Sillimanite

-10.17

a

Sillimanite

-17.44

-----

Sillimanite

-22.0

a

0.5 H

References: (1) Bandstra et al., 2008; (2) Palandri and Kharaka, 2004; (3) Burch et al., 1993; (4) Soler and Lasaga, 1996; (5)Rochelle and Noy, 2000 –also reported in Soler et al., 2006–.

Appendix. Thermodynamic data. Table A.1 Equilibrium constants (log Keq) and stoichiometric coefficients for equilibria in solution. Reactions are written as the destruction of 1 mole of the species in the first column Species Al(OH)2+ Al(SO4)2AlO2AlOH++ AlSO4+ CO2(aq) CO3-CaCO3(aq) CaCl+ CaCl2(aq) CaHCO3+ CaOH+ CaSO4(aq) Fe(OH)2(aq) Fe(OH)3Fe(OH)4-FeCO3(aq) FeCl+ FeCl2(aq) FeCl4-FeHCO3+ FeOH+ FeSO4(aq) H2SiO4-HAlO2(aq) HSO4HSiO3KCl(aq) KHSO4(aq) KOH(aq) KSO4-

log K 1.0594E+01 -4.9000E+00 2.2879E+01 4.9564E+00 -3.0100E+00 -6.3414E+00 1.0325E+01 7.0088E+00 7.0039E-01 6.5346E-01 -1.0429E+00 1.2850E+01 -2.1004E+00 2.9089E+01 3.9489E+01 5.4489E+01 1.4088E+01 8.6544E+00 1.0953E+01 6.5500E+00 5.7694E+00 1.7989E+01 6.2894E+00 2.2960E+01 1.6431E+01 -1.9755E+00 9.9422E+00 1.5004E+00 -8.0584E-01 1.4460E+01 -8.7500E-01

Stoichiometric Coefficients Ca++ Mg++ Na+ K+ HCO30.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 1.00 1.00 0.00 0.00 0.00 1.00 1.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 1.00 1.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 1.00 0.00

Al+++ 1.00 1.00 1.00 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00

Fe+++ 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

SiO2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00

SO4-0.00 2.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 1.00 0.00 0.00 1.00 0.00 1.00

H+ -2.00 0.00 -4.00 -1.00 0.00 1.00 -1.00 -1.00 0.00 0.00 0.00 -1.00 0.00 -3.00 -4.00 -5.00 -2.00 -1.00 -1.00 -1.00 -1.00 -2.00 -1.00 -2.00 -3.00 1.00 -1.00 0.00 1.00 -1.00 0.00

Cl0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 2.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 2.00 4.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00

O2(aq) H2O 0.00 2.00 0.00 0.00 0.00 2.00 0.00 1.00 0.00 0.00 0.00 -1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 -0.25 2.50 -0.25 3.50 -0.25 4.50 -0.25 0.50 -0.25 0.50 -0.25 0.50 -0.25 0.50 -0.25 0.50 -0.25 1.50 -0.25 0.50 0.00 2.00 0.00 2.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00

Mg4(OH)4++++ MgCO3(aq) MgCl+ MgHCO3+ MgSO4(aq) NaAlO2(aq) NaCO3NaCl(aq) NaHCO3(aq) NaHSiO3(aq) NaOH(aq) NaSO4OHHSFe++ SO3-S2-Fe(OH)2+ Fe(OH)3(aq) Fe(OH)4Fe(SO4)2FeCO3+ FeCl++ FeCl2+ FeCl4FeOH++ FeSO4+ H2S(aq) H2SO3(aq) HSO3S-SO2(aq)

3.9750E+01 7.3562E+00 1.3865E-01 -1.0329E+00 -2.4125E+00 2.3627E+01 9.8156E+00 7.8213E-01 -1.5573E-01 8.2984E+00 1.4799E+01 -8.2000E-01 1.3991E+01 1.3832E+02 8.4894E+00 4.6625E+01 2.4338E+02 5.6700E+00 1.2000E+01 2.1600E+01 -3.2137E+00 6.1807E-01 8.1466E-01 -2.1300E+00 7.9000E-01 2.1900E+00 -1.9170E+00 1.3134E+02 3.7412E+01 3.9423E+01 1.5126E+02 3.7568E+01

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

4.00 1.00 1.00 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 1.00 0.00 1.00 0.00 0.00 1.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 1.00 0.00 1.00 2.00 0.00 0.00 0.00 2.00 0.00 0.00 0.00 0.00 0.00 1.00 1.00 1.00 1.00 1.00 1.00

-4.00 -1.00 0.00 0.00 0.00 -4.00 -1.00 0.00 0.00 -1.00 -1.00 0.00 -1.00 1.00 -1.00 0.00 2.00 -2.00 -3.00 -4.00 0.00 -1.00 0.00 0.00 0.00 -1.00 0.00 2.00 2.00 1.00 0.00 2.00

0.00 0.00 1.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 2.00 4.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 -2.00 -0.25 -0.50 -3.50 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 -2.00 -0.50 -0.50 -2.00 -0.50

4.00 0.00 0.00 0.00 0.00 2.00 0.00 0.00 0.00 1.00 1.00 0.00 1.00 0.00 0.50 0.00 -1.00 2.00 3.00 4.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 -1.00

Table A.2 Equilibrium constants (log Keq) and stoichiometric coefficients for mineral reactions in the grout. Reactions are written as the dissolution of 1 mole of mineral Mineral

log K

Alite-Mg 9.9999E+02 Belite-Mg 9.9999E+02 Aluminate-Mg 9.9999E+02 Ferrite--Mg 9.9999E+02 Calcite 1.8542E+00 Anhydrite -4.2970E+00 Brucite 1.6298E+01 Hydrotalcite 7.3684E+01 Portlandite 2.2556E+01 CSH-00 -1.2000E+00 CSH-02 1.9648E+00 CSH-04 6.4767E+00 CSH-06 1.3271E+01 CSH-08 2.4631E+01 CSH-10 1.4583E+01 CSH-12 1.8801E+01 CSH-14 2.3124E+01 CSH-1667 2.9133E+01 Ettring-Al10 5.6822E+01 Ettring-Al08 5.6273E+01 Ettring-Al06 5.5867E+01 Ettring-Al04 5.5535E+01 Ettring-Al02 5.5279E+01 Ettring-Al00 5.5164E+01 Tricarboal 8.6196E+01 Monocarb-Al10 8.0577E+01 Monocarb-Al08 7.8984E+01 Monocarb-Al06 7.7533E+01 Monocarb-Al04 7.6158E+01 Monocarb-Al02 7.4857E+01 Monocarb-Al00 7.3699E+01 Syngenite -7.6001E+00 Monosulf-Al10 7.2462E+01 Monosulf-Al08 7.0945E+01

Stoichiometric Coefficients Ca++ Mg++ Na+ K+ HCO32.95 0.05 0.00 0.00 0.00 1.97 0.03 0.00 0.00 0.00 2.95 0.05 0.00 0.00 0.00 3.93 0.07 0.00 0.00 0.00 1.00 0.00 0.00 0.00 1.00 1.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 4.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.23 0.00 0.00 0.00 0.00 0.56 0.00 0.00 0.00 0.00 1.03 0.00 0.00 0.00 0.00 1.82 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 1.20 0.00 0.00 0.00 0.00 1.40 0.00 0.00 0.00 0.00 1.67 0.00 0.00 0.00 0.00 6.00 0.00 0.00 0.00 0.00 6.00 0.00 0.00 0.00 0.00 6.00 0.00 0.00 0.00 0.00 6.00 0.00 0.00 0.00 0.00 6.00 0.00 0.00 0.00 0.00 6.00 0.00 0.00 0.00 0.00 6.00 0.00 0.00 0.00 3.00 4.00 0.00 0.00 0.00 1.00 4.00 0.00 0.00 0.00 1.00 4.00 0.00 0.00 0.00 1.00 4.00 0.00 0.00 0.00 1.00 4.00 0.00 0.00 0.00 1.00 4.00 0.00 0.00 0.00 1.00 1.00 0.00 0.00 2.00 0.00 4.00 0.00 0.00 0.00 0.00 4.00 0.00 0.00 0.00 0.00

Al+++ 0.00 0.00 2.00 2.00 0.00 0.00 0.00 2.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.00 1.60 1.20 0.80 0.40 0.00 2.00 2.00 1.60 1.20 0.80 0.40 0.00 0.00 2.00 1.60

Fe+++ 0.00 0.00 0.00 2.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.40 0.80 1.20 1.60 2.00 0.00 0.00 0.40 0.80 1.20 1.60 2.00 0.00 0.00 0.40

SiO2 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 1.16 1.39 1.72 2.27 1.00 1.00 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

SO4-- H+ 0.00 -6.00 0.00 -4.00 0.00 -12.00 0.00 -20.00 0.00 -1.00 1.00 0.00 0.00 -2.00 0.00 -14.00 0.00 -2.00 0.00 0.00 0.00 -0.46 0.00 -1.12 0.00 -2.06 0.00 -3.64 0.00 -2.00 0.00 -2.40 0.00 -2.80 0.00 -3.34 3.00 -12.00 3.00 -12.00 3.00 -12.00 3.00 -12.00 3.00 -12.00 3.00 -12.00 0.00 -15.00 0.00 -13.00 0.00 -13.00 0.00 -13.00 0.00 -13.00 0.00 -13.00 0.00 -13.00 2.00 0.00 1.00 -12.00 1.00 -12.00

Cl0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

O2(aq) H2O 0.00 3.00 0.00 2.00 0.00 6.00 0.00 10.00 0.00 0.00 0.00 0.00 0.00 2.00 0.00 15.00 0.00 2.00 0.00 0.00 0.00 0.69 0.00 1.68 0.00 3.09 0.00 5.46 0.00 2.86 0.00 3.31 0.00 3.75 0.00 4.34 0.00 38.00 0.00 38.00 0.00 38.00 0.00 38.00 0.00 38.00 0.00 38.00 0.00 38.00 0.00 17.00 0.00 17.00 0.00 17.00 0.00 17.00 0.00 17.00 0.00 17.00 0.00 1.00 0.00 18.00 0.00 18.00

Monosulf-Al06 Monosulf-Al04 Monosulf-Al02 Monosulf-Al00 Gibbsite Ferrihydrite

6.9571E+01 6.8271E+01 6.7047E+01 6.5964E+01 7.7559E+00 4.8910E+00

4.00 4.00 4.00 4.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00

1.20 0.80 0.40 0.00 1.00 0.00

0.80 1.20 1.60 2.00 0.00 1.00

0.00 0.00 0.00 0.00 0.00 0.00

1.00 1.00 1.00 1.00 0.00 0.00

-12.00 -12.00 -12.00 -12.00 -3.00 -3.00

0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00

18.00 18.00 18.00 18.00 3.00 3.00

Table A.3 Equilibrium constants (log Keq) and stoichiometric coefficients for mineral reactions in the rock. Reactions are written as the dissolution of 1 mole of mineral. Mineral

log K

Alite-Mg 9.9999E+02 Belite-Mg 9.9999E+02 Aluminate-Mg 9.9999E+02 Ferrite--Mg 9.9999E+02 Calcite 1.8542E+00 Gypsum -4.4729E+00 Anhydrite -4.2970E+00 Brucite 1.6298E+01 Hydrotalcite 7.3684E+01 Portlandite 2.2556E+01 CSH-00 -1.2000E+00 CSH-02 1.9648E+00 CSH-04 6.4767E+00 CSH-06 1.3271E+01 CSH-08 2.4631E+01 CSH-10 1.4583E+01 CSH-12 1.8801E+01 CSH-14 2.3124E+01 CSH-1667 2.9133E+01 Ettring-Al10 5.6822E+01 Ettring-Al08 5.6273E+01 Ettring-Al06 5.5867E+01 Ettring-Al04 5.5535E+01 Ettring-Al02 5.5279E+01 Ettring-Al00 5.5164E+01 Tricarboal 8.6196E+01 Monocarb-Al10 8.0577E+01 Monocarb-Al08 7.8984E+01 Monocarb-Al06 7.7533E+01 Monocarb-Al04 7.6158E+01 Monocarb-Al02 7.4857E+01 Monocarb-Al00 7.3699E+01 Syngenite -7.6001E+00 Monosulf-Al10 7.2462E+01

Stoichiometric Coefficients Ca++ Mg++ Na+ K+ HCO32.95 0.05 0.00 0.00 0.00 1.97 0.03 0.00 0.00 0.00 2.95 0.05 0.00 0.00 0.00 3.93 0.07 0.00 0.00 0.00 1.00 0.00 0.00 0.00 1.00 1.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 4.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.23 0.00 0.00 0.00 0.00 0.56 0.00 0.00 0.00 0.00 1.03 0.00 0.00 0.00 0.00 1.82 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 1.20 0.00 0.00 0.00 0.00 1.40 0.00 0.00 0.00 0.00 1.67 0.00 0.00 0.00 0.00 6.00 0.00 0.00 0.00 0.00 6.00 0.00 0.00 0.00 0.00 6.00 0.00 0.00 0.00 0.00 6.00 0.00 0.00 0.00 0.00 6.00 0.00 0.00 0.00 0.00 6.00 0.00 0.00 0.00 0.00 6.00 0.00 0.00 0.00 3.00 4.00 0.00 0.00 0.00 1.00 4.00 0.00 0.00 0.00 1.00 4.00 0.00 0.00 0.00 1.00 4.00 0.00 0.00 0.00 1.00 4.00 0.00 0.00 0.00 1.00 4.00 0.00 0.00 0.00 1.00 1.00 0.00 0.00 2.00 0.00 4.00 0.00 0.00 0.00 0.00

Al+++ 0.00 0.00 2.00 2.00 0.00 0.00 0.00 0.00 2.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.00 1.60 1.20 0.80 0.40 0.00 2.00 2.00 1.60 1.20 0.80 0.40 0.00 0.00 2.00

Fe+++ 0.00 0.00 0.00 2.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.40 0.80 1.20 1.60 2.00 0.00 0.00 0.40 0.80 1.20 1.60 2.00 0.00 0.00

SiO2 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 1.16 1.39 1.72 2.27 1.00 1.00 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

SO4-- H+ 0.00 -6.00 0.00 -4.00 0.00 -12.00 0.00 -20.00 0.00 -1.00 1.00 0.00 1.00 0.00 0.00 -2.00 0.00 -14.00 0.00 -2.00 0.00 0.00 0.00 -0.46 0.00 -1.12 0.00 -2.06 0.00 -3.64 0.00 -2.00 0.00 -2.40 0.00 -2.80 0.00 -3.34 3.00 -12.00 3.00 -12.00 3.00 -12.00 3.00 -12.00 3.00 -12.00 3.00 -12.00 0.00 -15.00 0.00 -13.00 0.00 -13.00 0.00 -13.00 0.00 -13.00 0.00 -13.00 0.00 -13.00 2.00 0.00 1.00 -12.00

Cl0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

O2(aq) H2O 0.00 3.00 0.00 2.00 0.00 6.00 0.00 10.00 0.00 0.00 0.00 2.00 0.00 0.00 0.00 2.00 0.00 15.00 0.00 2.00 0.00 0.00 0.00 0.69 0.00 1.68 0.00 3.09 0.00 5.46 0.00 2.86 0.00 3.31 0.00 3.75 0.00 4.34 0.00 38.00 0.00 38.00 0.00 38.00 0.00 38.00 0.00 38.00 0.00 38.00 0.00 38.00 0.00 17.00 0.00 17.00 0.00 17.00 0.00 17.00 0.00 17.00 0.00 17.00 0.00 1.00 0.00 18.00

Monosulf-Al08 7.0945E+01 Monosulf-Al06 6.9571E+01 Monosulf-Al04 6.8271E+01 Monosulf-Al02 6.7047E+01 Monosulf-Al00 6.5964E+01 Gibbsite 7.7559E+00 Ferrihydrite 4.8910E+00 Quartz -4.0056E+00 An29Ab71 1.0766E+01 Maximum_Micr -2.9424E-01 Ann55Phl45 4.6747E+01 Muscovite 1.3567E+01 Clinochlore- 6.7222E+01 Cordierite_h 4.9792E+01 Sillimanite 1.6302E+01 Siderite 8.3026E+00 Pyrite 2.2591E+02 Analcime 6.1267E+00 Laumontite 1.3642E+01 Mesolite 1.3601E+01 Natrolite 1.8502E+01 Scolecite 1.5859E+01 Stilbite 1.0110E+00 Gismondine 4.1717E+01 Mordenite -5.2288E+00 Wairakite 1.8052E+01 Prehnite 3.2914E+01 Foshagite 6.5906E+01 Gyrolite 2.2893E+01 Hillebrandit 3.6815E+01 Okenite 1.0370E+01 Tobermorite14 6.3811E+01 Saponite-Ca 2.6268E+01 Saponite-H 2.5310E+01 Saponite-K 2.5986E+01 Saponite-Mg 2.6230E+01 Saponite-Na 2.6324E+01

4.00 4.00 4.00 4.00 4.00 0.00 0.00 0.00 0.29 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.66 0.00 1.00 1.02 2.00 0.29 1.00 2.00 4.00 2.00 2.00 1.00 5.00 0.17 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.35 0.00 5.00 2.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3.00 3.00 3.00 3.17 3.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.71 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.96 0.00 0.68 2.00 0.00 0.14 0.00 0.36 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.33

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.33 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

1.60 1.20 0.80 0.40 0.00 1.00 0.00 0.00 1.29 1.00 1.00 3.00 2.00 4.00 2.00 0.00 0.00 0.96 2.00 1.99 2.00 2.00 2.18 4.00 0.94 2.00 2.00 0.00 0.00 0.00 0.00 0.00 0.33 0.33 0.33 0.33 0.33

0.40 0.80 1.20 1.60 2.00 0.00 1.00 0.00 0.00 0.00 1.65 0.00 0.00 0.00 0.00 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.00 2.71 3.00 3.00 3.00 3.00 5.00 1.00 0.00 0.00 2.04 4.00 3.01 3.00 3.00 6.82 4.00 5.06 4.00 3.00 3.00 3.00 1.00 2.00 6.00 3.67 3.67 3.67 3.67 3.67

1.00 1.00 1.00 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

-12.00 -12.00 -12.00 -12.00 -12.00 -3.00 -3.00 0.00 -5.16 -4.00 -11.65 -10.00 -16.00 -16.00 -6.00 -2.00 1.00 -3.84 -8.00 -7.96 -8.00 -8.00 -8.72 -16.00 -3.76 -8.00 -10.00 -8.00 -4.00 -4.00 -2.00 -10.00 -7.32 -6.99 -7.32 -7.32 -7.32

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 -0.41 0.00 0.00 0.00 0.00 -0.25 -3.75 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

18.00 18.00 18.00 18.00 18.00 3.00 3.00 0.00 2.58 2.00 6.83 6.00 12.00 9.00 3.00 0.50 -0.50 2.92 8.00 6.63 6.00 7.00 11.69 17.00 5.35 6.00 6.00 5.50 4.50 3.17 3.00 15.50 4.66 4.66 4.66 4.66 4.66