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Presented by Carl Zipper, Ph.D.

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1 Presented by Carl Zipper, Ph.D.
AN EXPERT REPORT ON THE GEOLOGIC HAZARDS IN THE KARST REGIONS OF VIRGINIA AND WEST VIRGINIA INVESTIGATIONS AND ANALYSIS CONCERNING THE PROPOSED MOUNTAIN VALLEY GAS PIPELINE Presented by Carl Zipper, Ph.D. Based on a Report by Ernst H. Kastning, Ph.D. Consulting Geologist and Professor of Geology (Retired) Department of Geology, Radford University Forum on Natural Gas Pipelines Roanoke College, Colket Center, Roanoke, Virginia 12 October 2016

2 and Significant Environmental Concerns
To date, A High-Pressure, 42-inch, Natural Gas Pipeline Has Never Been Constructed Across the Appalachian Fold Belt. There are geotechnical reasons for this… and Significant Environmental Concerns

3 Karst Region of Proposed Mountain Valley Pipeline
Map from Roanoke Times Karst Region of Proposed Mountain Valley Pipeline (mileposts and ).

4 KARST – An assemblage of landforms that have been produced primarily by the dissolution of bedrock.
Characteristics of Karst Sculpted and/or pitted bedrock – exposed or beneath the soil Dissolutionally enlarged openings – pores, fractures (joints, faults) Springs – typically discrete with relatively large discharges Caves –great variety in size Sinkholes Sinking Streams Highly anisotropic – spatially variable openings and flow conditions Channelized groundwater flow (Photo is not from project area)

5 Project Area’s Ridges and Valleys, Karst Bedrock, and Sinkholes
Karst bedrock with sinkholes Steep slopes with weak soils, and enhanced seismic risk, also occurs in the area (not shown)

6 GEOLOGIC HAZARDS Vulnerability - Groundwater Contamination
Enhanced Potentials for Surface Collapse Accelerated Erosion Slope Instability Weak Soils Seismic Risk

7 Groundwater Contamination
Karst Terrains are uniquely vulnerable. Introduced contaminants will quickly and efficiently move through karst aquifers to springs and wells. Thousands of people living in these potentially impacted areas depend on groundwater to supply their homes. Groundwater contamination would be a serious problem should a pipeline rupture in karst terrain. The pipe would carry liquids (formed via synthesis, and contaminants) as well as gases – groundwater contamination risk.

8 Enhanced Potential for Surface Collapse
Construction of a pipeline in mountainous terrain would likely alter hydrologic flows by channelizing surface and/or groundwater. Should a pipeline trench intersect below-ground karst features, collapse of the surface may occur. Additionally, an infilled pipeline trench may become a conduit for groundwater flow. In that case, particles in the fill are conveyed downstream, causing an expanding cavity to develop whereby its roof thins and collapses, forming sinkholes. Collapses would weaken the integrity of the trench fill, perhaps leading to failure of the pipe.

9 Slope Instability Unconsolidated geologic material on steep slopes should not be considered as stable - Movement of this material will threaten pipeline integrity. Failure and movement of material may easily be induced by excess rainfall and/ or even seismic events, even if of small magnitude. Project analysis does not consider increased frequency and intensity of rainfall, predicted as climate change – and occurring now. Over half of the proposed MVP route from Monroe to Roanoke counties has slopes ≥20 percent grade ~20 percent of the slopes along this route ≥ 35 % grade.

10 Landslide Hazard Ratings
Source: 2011 New River Valley Regional Commission’s Hazard Mitigation Plan,

11 Weak Soils Soils on steep slopes can be subject to the slow and perisistent downslope movement known as ‘soil creep.’ This is true even without extreme precipitation or seismic activity. Weak soils would threaten the integrity of underground structures such as pipelines, especially lines that run horizontally along slopes. Soils on steep slopes should not be considered as stable. Several soil groups in the proposed corridors are high in plasticity – including some on steep slopes. This results in poor drainage and low bearing strength that can induce downslope movement.

12 Diagrams of Proposed Pipeline Burial
As the Pipeline Ages, Internal (and possibly External) Corrosion will Cause Reduction of Material Strength. Source: Drawing from Kastning (2016) based on MVP Application and Kastning Report Contents.

13 Seismic Risk The proposed pipeline route passes through the Giles County Seismic Zone. Recent geophysical investigations have identified this area to have enhanced seismic risk. A major seismic event would threaten the integrity of the pipeline. Even moderate seismic activity, especially in combination with other conditions (karst, severe slopes, weak soils) would threaten integrity of the pipe. By extension, a seismic induced event may easily threaten the flow and quality of groundwater.

14 Giles County Seismic Zone
Source: Virginia Department of Mines, Minerals

15 Giles County Seismic Zone
“ … there is ongoing tectonism in the region with multiple zones of seismicity …” Giles County Seismic Zone Biryol et al. (2016), Journal of Geophysical Research: Solid Earth, DOI: /2015JB

16 Three Examples of Geologic Hazards Along the Route of the Proposed Pipeline

17 Three Examples of Geologic Hazards Along the Route of the Proposed Pipeline
Sinking Creek Crossing Canoe Cave Mt. Tabor Karst Sinkhole Plain

18 Canoe Cave Area, Giles County, VA

19 Mt. Tabor Karst Sinkhole Plain, Montgomery County, VA
Map from Virginia DCR submittal to FERC

20 Conclusions Construction of a large-diameter natural gas pipeline across the Appalachian fold belt is unprecedented. The terrain’s high relief with weak soils, complex geology (karst), vulnerable groundwaters, and seismic potential are hazards: Create severe risks to the pipeline - and to water sources upon which residents depend. The hazards have potential to interact – as they co-occur within the same terrains – causing greater risks of negative consequences than do the individual hazards acting alone. MVP has not addressed geologic hazards adequately. FERC should reject MVP’s application.

21 Thanks to the many individuals and community groups supporting Dr
Thanks to the many individuals and community groups supporting Dr. Kastning’s Study


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