Today was an early start to survey a new location at the creek. As before we used the falling head test at multiple locations in the creek. This section of the creek turned out to contain sediment that was more rocky in nature than the more sandy conditions at the first location. There was a top layer of sand that was rather shallow with a layer of rocks underneath. There seemed to be this layer of rocks at approximately the same depth across the whole area tested, so we expect differences in the values calculated for this location compared to the first. We collected sand from the location we had tested to bring back to the lab so we could try to confirm the K values by testing the sand in the lab. We set the column up to be tested tomorrow as the water was very murky and we wanted to allow the sand time to settle.
Once we were back in the lab we proceeded to test a new setup of two layers of different sand after having let it settle overnight. We tested different depths into the two layers of sand by starting with the column deep through both sands and slowly moving the column up half an inch between trials. Our goal from setting the test up and while carrying it out was to disturb the layers as little as possible to be more sure that the interface between the layers was where we thought it was and that the layers didn't get mixed greatly with each other. A depiction of the comparison of our measured experimental values with our model values generated with MODFLOW is shown below.
Below are some images from our testing the new location at the creek and of our layered sand test.
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| Matt and David |
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| Matt and David (with Jessica behind on bridge) |
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| Superior sand on top, F65 on the bottom |
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