Hi,

I am attempting to plot a piper plot and I am confused as to which values to input. I understand that there are values for HCO3 and CO3 but the data available to me have the following:

1) Inorg. Bicarb. Alk. CaCO3

2) Inorg. Bicarb. Alk. HCO3

3)Inorg Carbonate Alk. CaCO3

4) Inorg. Carbonate Alk. CO3

The dataset I am working with has the Carbonate Alk. (CaCO3 and CO3) as below the Limit of Reporting (LOR). There are values in the Inorg. Bicarb. Alk. section but prior to 2013, all the data is reported as Inorg. Bicarb. Alk. HCO3. I am confused by this and welcome any comment/discussion on the following:

a) Do I use Inorg. Bicarb. Alk. CaCO3 as my preferred post-2013 data and include it under the CO3 value for the Piper Plot or include it under HCO3? As for pre-2013 data, I am leaning towards including the data which is presented as Bicarb. Alk. HCO3 under HCO3 for the Piper plot as it seems logical - Would this be the correct approach?

b) Given that the Carbonate Alk. CO3 and CaCO3 data are all below LOR, does that just mean that the water is HCO3 rich and I do not have data for CO3? Should I just use a 1/2 LOR for the CO3 values?

Thanks for your help with this.

Cheers,

Dilip