Dear Prashant, 

It depends on the method you will apply. Each method assesses vadose zone impact in a different way. If you have chosen the method to use, i can help you with that.

cheers

Dear Evangelos,

Thanks a lot!

I will send you an email.

What exactly are you looking for?  My work on ground temperatures used the Kasuda equation which had temperature at ground depth calculations that were dependent on soil humidity.  There is a lot of study done in Canada even as far back as the turn of the last century that may help you depending on what you are looking for.  Even here in the Ozarks there are ground water studies done for the depression zones around heavy draw down areas around the cities that rely on ground water for the water systems of the cities.  

Good luck and tell us what you are looking for.

George 

Hi,

Not sure what exactly you are going to investigate, but my two papers could be useful:

The nitrate time bomb: A numerical way to investigate nitrate storage and lag time in the unsaturated zone

Catchment-scale vulnerability assessment of groundwater pollution from diffuse sources using the DRASTIC method: A case study

Thanks,

Lei

Hello all, I am having the same problem, I have spent some time trying to understand how to derive the ratings for the impact of the vadose zone. I am using DRASTIC.

DRASTIC uses a rating system for each parameter and evaluates higher rate to shallower water table. The ratings are assigned according to the dept you have. If you are using any GIS software, you can code a conditional in the raster calculator to assigned a value to each depth. The ratings are classified by 10 categories, each one of 5 meters. So, if you water table is between 0 and 5 meters depth, you will have a rating of 10, 5 to 10, rating of 9 and so on. Each rating then would have to be multiply by its own weigth. In DRASTIC, if I recall correctly, for D is 5.

Well,

Lab case study in the attached pdf

Sincerely

I have the same problem. From the geological map, I obtained the vadose zone media as black ashes, eutaxitic welded tuffs and pumice. The rating of these is not given in the DRASTIC model. How do I go about it?

Well,

Tuffs and pumice by the meaning of hydraulic properties look like as silty Sandstone.

Regards