ASP: Acid Snow Projects
by Dr. Michael J.Demchik
The acid snow project began in a small way in 1985. When it snowed at Jefferson High School samples of the snow were brought in and analyzed according to the snow collecting and analyzing protocol devised by Dr. Randy Borys of the Desert Research Institute in Reno, Nevada.
The preparation for the collection of acid snow starts with a clean polyethylene container which can often be found in most supermarkets. A pint size is usually preferred and should be washed cleanly with distilled water. Allowing the containers to stand overnight with distilled water in it will insure cleanliness. Snow should be collected in them and the collector should were plastic gloves. One should be careful not to have anything from oneself fall into the sample while the collection is taking place.Samples should be taken from a fresh snow surface. The samples may be collected in a plastic bucket prepared in the same manner.
When collecting, always collect from the downwind side, so as not to disturb or influence the snow in any way. The containers should be closed and then placed into a ziploc bag. The sample should be kept frozen and apprpopriately labelled until ready for testing. The snow should be allowed to thaw at room temperature and the container should remain closed. It should be analyzed with a probe rom a pH meter which is corrected for temperature. The testing should tke place as soon as the sample melts. The sample could easily influence the readings because the carbon dioxide in the air, so take an immediate reading.
The collected samples should be out of the snow shadow of the house or any other projecting object such as a tree. Avoid the edge of the road and any other local influences that might affect the collection.
Any stream under study should be checked out for pH, disolved oxygen and dissolved carbon dioxide, as well as, total dissolved solids and magnesium and calcium hardness. Other tests such as nitrates, phosphates, silicates and E.coli test. The E.coli can be tested for by the addition of 2mL of water to the test sample of lactose and indicator. The presence of a yellow to orange color indicates the presence of the E.coli.
Activities such as the presence of oxides of nitrogen in the sample can be demonstrated by dissolving copper in nitric acid and bubbled through water with phenol red added as an indicator shows some dramatic changes once the sample becomes highly acidic. In other situations microenvironmental generations of oxides of nitrogen and sulfur dioxide can create an interesting visual view with universal indiccator and a collecting area. The results are kind of dramatic.
These activities provide an excellent way of getting into the study of acid snow with a strong activity base.