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E-coli and pathogens

Fri, 12/19/2008 - 2:33pm — nick
Has anyone attempted to model e-coli, cryptosporidium, giardia, or other pathogens? Do the coliform decay rates in the W2 manual adequately represent e-coli? Thanks much.
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Water Quality
Fri, 12/26/2008 - 1:22pm — chris

Hi Nick, The coliform decay rates in the W2 manual are representative. As you can see, there's a very wide range. If possible you should try to get in situ measurements. chris
Mon, 07/12/2010 - 5:59am — MohsenH

As I know commonly unit of coliform is MPN/m3 but in page b-4 of CE-Qual manual V3.6 (B-3 formula) unit of coliform concentration is gr/m3. I do not know which one is correct and how can I convert them together.
Tue, 07/13/2010 - 11:48am — chris

Hi Mohsen, Either unit would work. I'm not sure how to convert one to the other, but you could choose to use MPN/m3 rather than mg/l. Chris
Mon, 07/12/2010 - 6:00am — MohsenH

In page B-4 OF manual V3.6 formula (B-3) for “Coliform System Loss” have two terms: First Order Decay & Settling. In example which I downloaded (DeGray) from the website of this software, the second term of Coliform Loss in GC3 (settling) is assumed zero. I did not find the reason of that and I do not know what I should do about the second term in my thesis. Also, I do not have any idea about the other parameters of this card (W2-control, Water Quality, suspended solid & Generic C). Would you please update me what I should use for: 1- Generic Q10 [C-ARBQ10, 2- Generic settling Rate [CG1DK], 3- Generic Settling Rate [CGS]?
Tue, 07/13/2010 - 12:04pm — chris

Mohsen, In the generic constituent card description in the V3.6 manual (around page C-140) there is a table containing typical coliform decay rates (CG1DK). Also located there is a suggested value for the Arhennius temperature rate value (CGQ10=1.04). Chris