IMPACTS OF HIGH-VOLUME HORIZONTAL HYDRAULIC FRACTURING ACTIVITIES ON STREAMS OF THE NORTHEASTERN UNITED STATES: IMPLICATIONS FOR EASTERN BROOK TROUT (SALVINUS FONTANALIS)
The high-volume horizontal hydraulic fracturing (HVHHF) method of natural gas extraction has come into extensive use in the Marcellus and Utica Shale deposits of the northeastern United States. Environmental effects of HVHHF could further diminish the population of native eastern brook trout (Salvinus fontanalis), which is already reduced in its native range due to anthropogenic activities. In this dissertation, I first defined relationships between HVHHF activities and the stages of the brook trout life cycle through extensive literature review, then used these relationships to establish a research agenda. A subset of the identified potential pathways of influence were then investigated through a three-year, multi-seasonal empirical field study, which was conducted within a single central Pennsylvania State Forest subwatershed in which some first order headwater stream catchments had active HVHHF activity, while some had no drilling. Data collections included water chemistry measurements (pH, dissolved oxygen, conductivity, temperature, ion and metal concentrations) and biotic measurements of fish (abundance counts, lengths, and weights) and macroinvertebrates (abundance counts, identification, and application of diversity and tolerance indices). Year one (young-of-year: YOY) brook trout were found to be significantly longer and heavier in the controls as compared to the drilled catchments. Additionally, macroinvertebrate communities were richer and more diverse, with more even distributions of families, and greater proportions of pollution-sensitive species (a proxy for water quality and stream health), in the undrilled as compared to the drilled catchments. Water chemistry discrepancies were also observed, with the drilled streams having higher conductivity, higher concentrations of certain ions, and lower dissolved oxygen than the control streams. The presence of certain chemical markers in the water chemistry of the active drilling streams (chloride:bromide ratios and prevalent ions) are suggestive of produced water from the HVHHF process, signifying a direct link between brook trout health, macroinvertebrate distribution, and drilling activities.
Water resources management; brook trout; high-volume horizontal hydraulic fracturing; in-stream impacts; macroinvertebrates; Marcellus Shale; Salvinus fontinalis; Ecology; Environmental science
Walter, Michael Todd
Riha, Susan Jean; Sullivan, Patrick J.; Flecker, Alexander S.
Ph.D., Natural Resources
Doctor of Philosophy
dissertation or thesis