Next problem with PhreeqC

[Bernd Kottke <Bernd.Kottke@xxxxxxxxxxxxxxxxxxxxxxxx>]

Hello David,

some days ago we were in contact about the database llnl.dat. Now, we
have some problems modelling analyses of waters, which were in contact
with steel slags regarding species distribution.
I attached 3 of these analyses which have nearly the same composition
(CH1A, CH3A, CH4A). However, two of these analyses (CH3A and CH4A) do
not get convergence. We have just checked ion balance and it's ok. So
what's wrong with these analyses, since CH1A can be modelled without
problems ?

With regards,
Bernd

TITLE		 Ch 
SOLUTION	LDS	1 A
       	units   mg/l
        	pH      6.21     
	   	pe      3.65   
	   	temp    23.2
        
        	Ca		355.13            
        	Mg        	12.07   
        	Na        	0.83     
        	K         	0.69     
        	Fe        	27.01     
        	Al		0.33
	   	Cr		0.000055
	   	Mo		0.01963
	   	V         	0.07936
           
        	Alkalinity      	1291.17 as HCO3
        	S(6)            	4.60 as SO4
        	N(5)            	0.46 as NO3
        	F               	0.55
        	Cl			1.04

END

TITLE		Ch 
SOLUTION	EOS  3A
        	units   mg/l
		pH      6.3     
	  	pe      4.26   
	  	temp    22.6
        
        	Ca		276.92            
        	Mg        	11.16 
        	Na        	2.17 
        	K         	0.54     
        	Fe        	10.27     
     		Al		0.50 
	  	Cr		0.000055
	  	Mo		0.02343
	  	V         	0.10706
                      
        	Alkalinity      	1077 as HCO3
        	S(6)            	4.39 as SO4
        	N(5)            	0.54 as NO3
        	F  		   	0.04         
   	   	Cl 		   	0.99    

END

TITLE		Ch 
SOLUTION	EOS  4A    
	   	units   mg/l
        	pH      6.18     
	   	pe      4.18   
	   	temp    23.1
        
        	Ca		223.86            
        	Mg        	8.39
        	Na        	1.96
        	K         	1.62     
        	Fe        	34.84
        	Al		0.67
	   	Cr		0.000055
	   	Mo		0.01368
	   	V         	0.02986
                      
        	Alkalinity      	851.97 as HCO3
        	S(6)            	2.56 as SO4
        	N(5)            	0.52 as NO3
        	F			0.32
	   	Cl			0.89 

END

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n:Kottke;Bernd
tel;fax:++49-89-2180-6594
tel;work:++49-89-2180-6533
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url:http://www.hydrogeologie.uni-muenchen.de
org:Ludwig-Maximilians-Universität München;Department für Geo- und Umweltwissenschaften
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email;internet:Bernd.Kottke@xxxxxxxxxxxxxxxxxxxxxxxx
title:Dipl.-Geologe
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fn:Bernd Kottke
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