Cassie Thomas

Date of Award

Summer 8-2018

Document Type


Degree Name

Master of Science (MS)



First Advisor

David J. Janetski, Ph.D.

Second Advisor

Joseph E. Duchamp, Ph.D.

Third Advisor

Ellen H. Yerger, Ph.D.

Fourth Advisor

Eric J. Chapman


To improve understanding of ecological impacts from energy extraction, I evaluated stream macroinvertebrate communities in association with unconventional gas wells and drainage from abandoned coal mines. First, I analyzed habitat and macroinvertebrate data collected from 51 streams by the Western Pennsylvania Conservancy from 2013-2014. Contrary to expectations, habitat quality and macroinvertebrate community composition, including percent sediment- and pollution-tolerant taxa, were similar at sites with and without gas wells. Second, in 2017 I sampled macroinvertebrates using two sampling techniques from 12 sites within the Bear Run Watershed, where abandoned mine drainage has been treated for 10 years. I found poor recovery from mine drainage impacts, but conclusions about the degree of recovery differed with sampling method. Specifically, Hess samples indicated less recovery than kick net samples. My work suggests that unconventional wells do not negatively affect macroinvertebrate community structure or habitat and that recovery from AMD can take over a decade.