Date of Award
Master of Science
Increasing energy demand, coupled with the recent emphasis on domestic production, has resulted in an increase in natural gas exploration and pipeline construction in the central Appalachian region. Very little is known about the effects of natural gas pipeline construction on sediment production. The goals of this project were to measure erosion and examine the effects of vegetation and precipitation characteristics on erosion on a newly constructed pipeline in the Fernow Experimental Forest in West Virginia. The study explored whether seed rate, slope class, or aspect, influenced erosion. The cross country pipeline was buried beneath the surface on study hillslopes ranging from 30-68% and beneath a less steep segment with slopes ranging from 18-26%. A mixture of native herbaceous-plant seeds and straw mulch were applied following construction. Two different seeding rates were applied to compare vegetative recovery and to determine if increasing the seed rate would decrease erosion. A 1-time seed rate, or the normal Forest Service application rate, and a 3-time seed rate (1-time + twice that rate) were tested. Two aspects (northwest-facing and southeast-facing) and four precipitation variables (30-minute maximum intensity, duration, total rainfall amount, and time since last event) were defined. Sediment concentrations were compared for differences between two slopes, two seed rates, and two aspect classes. Precipitation variables were analyzed to identify those that could explain significant amounts of the variability in erosion from the pipeline. The 1-time seed rate sections produced less sediment than the 3-time seed rate sections, but this was probably more a function of subsurface flow differences associated with the sections seeded with the lighter rate and the water bar construction. Precipitation intensity explained the most variability in erosion. Study sites with gentler slopes produced less sediment than the steeper sections, as expected. As vegetation became established, sediment concentrations decreased for all study sections and reached low and relatively constant levels by approximately the end of August 2009.
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