Phreeqc

[o0bsn <o0bsn@xxxxxx>]

Hello Dr. Parkhurst,

My name is Barb Petrunic and I am a student at the University of New Brunswick 
working under the supervision of Kerry MacQuarrie and Tom Al.

I am trying to work through example problem 15 that is provided in the Phreeqc 
program however, I am having trouble understanding the rates data block for 
the Biomass in the problem.  I was wondering if you could answer a couple 
questions with regards to this example problem:

1) why does the "moles" of biomass have to be negative?

2) why is the "if" statement required in line 60 in the rates data block?

Thank-you very much for your help,

Barb