Methods
In order to conduct this
project we chose two different sites, which are affected by road salt use. Our
sites are located in the rain gardens in front and behind the Edgedome on the
Edgewood campus. We determined to gather soils samples before winter hits,
October 2006, and then towards spring when the snow melts, March 2007. At each
site we took samples at a half meter, one meter, and two meters in from the
curb. We also took a total of four samples at each distance and mixed them
together in a plastic bag. The tool we used to get the soil is a core sampler,
which is a metal tube. We pushed the tube into the soil about 10 inches, this
was an informal procedure; 10 inches worth of soil was then brought up. For each
sample we tested the top one to three inches and the seven to ten inches. We did
this see if salt concentration varies depending on how deep the soil was. We put
the soil samples into labeled bags, based on site and depth. Once our samples
were collected we did two tests to gather our data; tested the conductivity and
the chloride levels of each sites samples. Testing the conductivity was
important because this test gives a general idea of how many impurities are
dissolved in a water sample. The chloride test, told us how much is evident in
the soil.
Our first step for the conductivity test was to measure out
250mL of deionized water. We also weighed the water to 250g, to double check
that we had 250mL. Next we measured eight milliliters of soil and added it to
the two hundred and fifty milliliters of deionized water (it’s important to note
that even though we took and weighed the same amount of soil from each sample,
there was a tendency for the deeper samples to weigh more, we believe this could
be that the soil is more compact at the deeper levels). We then stirred the
solutions. Once the solutions were stirred we measured the conductivity by
sticking the conductivity meter into the solution. We documented our data.
Then we continued with the chloride test. We first filtered
the solutions by using the vacuum pump as follows: we added a filter to the top
and put our solution of soil and de-ionized water (per site measurement) in the
top of the machine. After 250 milliliters of our solution was filtered through
we were able to begin the chloride test. We then followed the low-range
instructions of the Chloride Test Kit to determine the amount of chloride in the
solutions. Again, this will then tell us how much salt is evident in the soil.
We then repeated the same procedure for the samples we took in March; which was
after the snow melted.