question about PHREEQC

[h2osoft@xxxxxxxx]

----- Forwarded by Michele Y Crouse/WRD/USGS/DOI on 06/12/01 07:45 a.m.
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                      Daniel Emilio                                                          
                      Martínez                 To:      h2osoft@xxxxxxxx                     
                      <demarti@xxxxxxx         cc:                                           
                      .ar>                     Subject: question about PHREEQC               
                                                                                             
                      06/11/01 05:50                                                         
                      p.m.                                                                   
                                                                                             
                                                                                             



Dear Mr.:

I'd like to make a question about the User's Guide of PHREEQC2.0,
specifically about the Example 11. This example is, acording the User's
Guide, derived from a sample calculation of the program PHREEQM (Appelo and
Postma, example 10.13, p. 431-434).
In page 239, line 9, the user's guide said "the number of exchange sites in
each cell is 1.1 mmol", which is according with the keyword data block
intructions given at page 82. Nevertheless, the referred PHREEQM example
states a CEC of 1.1 meq/L of pore water.
My question is: the nunmber of exchange sites must be given in mol or in
meq/L as in PHREEQM? and if the first is correct: it is claire how to
transform the measured CEC in meq/100 g of soil to meq/L of solution
(Appelo and Postma, 1993, Example 5.1. p.149), but, how can I make the
recalculation from meq/100 g soil to mol as requested in PHREEQC?
Thank you very much for your assistance.
Yours sincerely


Dr. Daniel Emilio Martínez
CONICET -
Centro de Geología de Costas y del Cuaternario
CC 722 - 7600 Mar del Plata
T.E. 0223 475 4060