TITLE Example 14.--Transport with equilibrium_phases, exchange, and surface reactions
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PLEASE NOTE: This problem requires database file wateq4f.dat!
             Arsenic data of Archer and Nordstrom (2002) included in 
             wateq4f.dat (PHREEQC Version 2.8).
             Results differ from WRIR 99-4259 because of revised data.
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SURFACE_SPECIES
        Hfo_wOH + Mg+2 = Hfo_wOMg+ + H+
        log_k -15.
        Hfo_wOH + Ca+2 = Hfo_wOCa+ + H+
        log_k -15.
SOLUTION 1 Brine
        pH      5.713
        pe      4.0     O2(g)   -0.7
        temp    25.
        units   mol/kgw
        Ca      .4655
        Mg      .1609
        Na      5.402
        Cl      6.642           charge
        C       .00396
        S       .004725
        As      .05 umol/kgw
END
USE solution 1
EQUILIBRIUM_PHASES 1
        Dolomite        0.0     1.6
        Calcite         0.0     0.1
SAVE solution 1
# prints initial condition to the selected-output file
SELECTED_OUTPUT
        -file ex14.sel
        -reset false
        -step
USER_PUNCH
        -head  m_Ca m_Mg m_Na umol_As pH
10 PUNCH TOT("Ca"), TOT("Mg"), TOT("Na"), TOT("As")*1e6, -LA("H+") 
END
PRINT
# skips print of initial exchange and initial surface to the selected-output file
        -selected_out false
EXCHANGE 1
        -equil with solution 1
        X       1.0
SURFACE 1
        -equil solution 1
# assumes 1/10 of iron is HFO
        Hfo_w           0.07    600.    30.
END
SOLUTION 0 20 x precipitation
        pH      4.6
        pe      4.0     O2(g)   -0.7
        temp    25.
        units   mmol/kgw
        Ca      .191625
        Mg      .035797
        Na      .122668
        Cl      .133704
        C       .01096
        S       .235153         charge
EQUILIBRIUM_PHASES 0
        Dolomite        0.0     1.6
        Calcite         0.0     0.1
        CO2(g)          -1.5    10.
SAVE solution 0
END
PRINT
        -selected_out true
ADVECTION
        -cells 1
        -shifts 200
	-print_frequency 20
END