In less than 24 hours, I packed up my dorm room, worked my last summer day, gave my final presentation, and returned back home to Chicago. Summer in Williamsburg has sadly come to close, but my research is far from conclusion. While time away has been relaxing, having nothing to do on the rainy days is hard to get used to, and I am anxious to get back in my lab!
I have come to realize that summer in Williamsburg is a little eerie. The brick walk ways throughout campus are commonly empty, except of course if you happen to trip on an out-of-place brick…in that case there is always a dog walker or tour group around. The basement of the Sadler Center is dark, the Market Place is closed, WaWa rarely has a line, and the terrace on a sunny Friday afternoon has open tables. And for those who have never seen Swem in the Summer…trust me, it’s like nothing you have ever seen before.
My name is Nancy Lauer and I am a junior at William and Mary majoring in environmental geology and environmental science. I am extremely excited to be working with Professor Jim Kaste on my particular research project this summer and next school year.
I will be looking at the concentrations of the low level cosmogenic radionuclide, sodium-22, in precipitation. Why would anybody ever care about sodium-22? We believe that sodium-22 has the potential to date young fresh waters using isotopic dating methods. If you have heard of carbon-14 dating…it’s the same idea. Carbon-14 dating using the known half life of carbon-14 (5730 years) in order to determine the age of organic matter. The issue with carbon-14 and other isotopes used for isotopic dating is that they have relatively long half lives and so they are useless for dating young fresh waters. Sodium-22 on the other hand has a half life of 2.6 years and is produced consistently in the earth’s atmosphere, reaching the earth’s surface as fallout in rain and snow. Currently, very little research has been done about the fallout rates of sodium-22, and this specific project has never been carried out in North America. However, by analyzing the consistency of sodium-22 fallout rates by measuring sodium-22 in precipitation samples, we can assess the potential of sodium-22 as an indicator of the residence time of young fresh waters.
Currently, we really have no easy means of dating young fresh waters…however, it is extremely important. Being able to calculate the residence time of a freshwater allows us to determine how quickly water in a given area is recharged and how quickly contaminants move through the water system. A key example of this can be seen from what happened in Woburn, Massachusetts in the 1970s. A leukemia cluster appeared in the area due to contaminated well water. The industries Beatrice Foods and W.R. Grace were brought to trial and accused of contaminating the groundwater in the area. However, without being able to measure the recharge rate of the groundwater system, it was difficult to prove in court that the contamination in the wells would have come from these industries during their operating lifetime.
I began collecting rain samples in January, and after a very dry March, I am thankful for a few rain showers. I am looking forward to being able to share my experience with you all. Stay tuned!