The answer to your question really depends on what kind of pollution you are trying to measure! One approach you could use would be to collect the snow using a very clean plastic or glass tool, melt it in a very clean plastic or glass container, and then test the water using a water pollution kit (as available from many suppliers such as the Carolina Biological Supply Company, Forestry Suppliers, or Wards). The problem with this, though, is that tests for many pollutants can be quite expensive.

You also may encounter a problem in that very low pollution levels will escape detection (since the kits are designed for use in normal water, which is more likely to show pollution). One way to solve this problem could be to melt a very large snow sample and then to concentrate it by gently evaporating water. You would have to be sure to keep track of how much the sample was concentrated by measuring the initial melt volume and concentrated volume!

To test the pollution of snow, you need to collect snow samples from the different regions in very clean containers. Once the snow melts, snow scientists run the water through a machine that measures the amounts of different elements. To do this is really costly and requires you to work at a university. A different method you could try that is less expensive and may give you some information about large particles that are in the snow is you can drip the water through a filter and look at the material on the filter under a microscope. Filter paper is not that expensive and it shouldn't be too hard to find a microscope you can use. The important thing to remember is that this will tell you how much pollution is in the snow *and* how much the snow has been contaminated since it fell--so you'll have to keep that in mind for a source of error and bias.Good luck!!

Well, there are a lot of different kinds of pollutants that could wind up in snow. What kind are you looking for?

The obvious way to do it is to find some way to measure the water content of the snow. If you are only concerned about solid pollutants, then take a sample of the snow, let it melt in a beaker and then let the water evaporate, and whatever solid is left behind is the pollutants. I'm not sure how you find volatile pollutants that would also evaporate - at least not in such a way that one could do for a science fair.