Association of Environmental & Engineering Geologists (AEG) To join AEG: Student membership is Free! Ask about our scholarships.

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1 Association of Environmental & Engineering Geologists (AEG) To join AEG: Student membership is Free! Ask about our scholarships.

2 What is the Association of Environmental & Engineering Geologists (AEG)? Our Mission: AEG contributes to its members professional success and the public welfare by providing leadership, advocacy, and applied research in environmental and engineering geology.

3 We Rock Your World What Geologists Do and How Our Work Improves Your Life Association of Environmental & Engineering Geologists Presenter s Name and Employment Presenter s Address

4 What is geology? The study of the earth and its processes, including rocks, soil, water, landforms, and how they all interact.

5 Rocks Hold water, oil, gas, and/or minerals that we use every day Are the basis for earth s landforms We build with it Soil We build on it We build with it We have, in the past, used to get rid of liquids we no longer needed Water We drink it and wash in it We use for electricity or manufacturing

6 What is applied geology? Applying the knowledge of the earth and its processes that we have learned through the ages to address problems that affect all of us every day, and to help make our world a better and safer place to live.

7 What do Environmental & Engineering Geologists and Hydrogeologists do? We identify, analyze, and mitigate natural and manmade hazards to protect property, public health and the environment. We investigate and analyze the earth materials present from the ground surface down into the earth to evaluate their suitability for support of proposed structures and to provide recommendations for foundation types based on subsurface conditions.

8 Why is this relevant and important to you? Environmental, Engineering, and Hydrogeologists work on: Natural hazards landslides, faulting and earthquakes, flooding, sinkholes, volcanoes, and glaciers Site Evaluations investigate sites for design and environmental considerations such as slope stability, seismic hazards, soil and groundwater contamination, and soil and rock properties for construction considerations Site Mitigation design and implement methodologies to clean-up contaminants in the soil and groundwater, and to stabilize earthen materials

9 TYPES OF NATURAL HAZARD PROJECTS: Identification and stabilization of landslide hazard areas Mapping of faults and earthquake prone areas Mapping of flood zones Identification of sinkhole prone areas and recommendations for fixing sinkholes Evaluations of volcanic activity probability Studies of potential glacier recesses Studies of potential sea level rise and its effects on man-made structures

10 NATURAL HAZARDS: Landslides Project: North Carolina Geological Survey Landslide Hazard Maps Program Increase public awareness of landslide hazards ID areas that need a site specific investigation Help reduce losses in the event of a landslide by influencing informed decisions Indicate high hazard areas for Emergency Response

11 North Carolina Geological Survey (NCGS) Landslide Hazard Maps Engineering Geologists Role: Identify areas of landslide activity Create models based on soil and rock properties Educate the public Peeks Creek Debris Flow Photo courtesy of NCGS

12 North Carolina Landslide Inventory Slope Movement Slope Movement Deposit Geodatabase As of Oct 1, 2011: 3,294 Landslides 3,251 Ancient Deposits 46 fatalities since structures destroyed or condemned since structures damaged since 1990

13 NATURAL HAZARDS: Impacts of Ground Subsidence Flood Risk Dam Freeboard Canal Capacity Sewer Capacity Stream Sediment Courtesy of AMEC

14 NATURAL HAZARDS PROJECT: Earth Fissures: Geologists in the Flood Control District of Maricopa County Studied earth fissures and surface flow conditions Found a high probability for earth fissures near the McMicken Dam near the foothills of the White Tank Mountains west of Phoenix Information helped influence the decision to replace a portion of the dam with stronger structure May have prevented failure protecting the downstream public and property.

15 NATURAL HAZARDS: Earthquakes USGS Shaking Hazard Map Courtesy of Fugro

16 Seismic Hazard (Earthquake) Assessment: Pre-construction Research Courtesy of Fugro

17 NATURAL HAZARDS: Ground Subsidence 1925 Subsidence is a consequence of withdrawing groundwater faster than it can be recharged Subsidence at Mendota, CA USGS Courtesy of AMEC

18 Ground Subsidence Examples 50 ft diameter, 40 ft deep sinkhole Newala Limestone, dolomitic limestone in Cobb County, GA EM-34 geophysical survey to detect additional subsurface karst terrain features

19 SITE EVALUATIONS: Nuclear power plants Dams Public buildings Former petroleum storage and hazardous wastes sites Roadway alignments and highway bridge locations Landfill sites

20 Nuclear Power Plant Siting SITE EVALUATIONS: It is a federal requirement that nuclear power plants be designed and built to withstand earthquake hazards Geology consultants identify evidence of faulting at the site which could mean the potential for earthquakes effecting the sites Geologists determine the likelihood of movement on that fault The work of the geologist is important for public and environmental safety Courtesy of Fugro

21 Operating Nuclear Power Reactors Courtesy of Fugro

22 SITE EVALUATIONS: Site Evaluations for Dams Engineering Geologist s Role: Determine optimum locations for new and replacement dams based on site foundation conditions. This is accomplished by using all available data including published reports, USGS mapping, subsurface explorations, geophysical investigations, etc. Provide recommendations on depth of shallow or deep foundations by evaluating the engineering properties of the soil and rock present at the site. Information Courtesy of AECOM

23 SITE EVALUATIONS PROJECT: Bridgeton, MO - Former gas station and new municipal building Drilled borings Sampled and tested soil Determined seismic potential Recommendations for the foundation design Courtesy of Geotechnology, Inc.

24 Bridgeton, MO Project (continued) Engineering Geology Investigation and evaluation of below-ground soil, rock, and water to develop recommendations for the design of the foundations of the structure Environmental Geology Design of vapor barrier and mitigation system to prevent hydrocarbon vapors from entering the building Courtesy of Geotechnology, Inc.

25 SITE EVALUATIONS PROJECT: Former DOT Hazardous Waste Disposal Area Project Scope: Strategic Logging of Soils From Subsurface Investigation Installed Wells to Monitor Groundwater Sampled Soil and Groundwater Engineering Geologist s Role: Performed Subsurface Investigation Prepared Conceptual Site Model Identified Potential Contaminants of Concern Designed and Implemented Remediation System to Clean Up Groundwater Information Courtesy of AECOM

26 SITE EVALUATIONS PROJECT: Rail Runner Express Engineering Geologist s Role: subsurface investigation conceptual geotechnical reports and project specifications to inform: rock and soil cut slope stability retaining wall stability embankment construction structure foundations Information Courtesy of Gannett Flemming, Inc., and

27 Phase II between Burlington Northern Santa Fe, through Waldo Canyon, along the median of I-25 to a connection with the Santa Fe Southern (SFS) Railway line. Consulting firm hired to develop and evaluate alternative alignments to select the Locally Preferred Alternative. Rail Runner Express ~ 4,800 riders per day Photo by Deb Green Completed in 14 months with a budget of $128 million Information Courtesy of Gannett Flemming, Inc., and

28 SITE EVALUATIONS PROJECT: Highway Bridge Locations Engineering Geologist s Role: Perform subsurface investigation to evaluate soil and rock for foundations of proposed bridge Provide recommendations for type(s) of bridge foundations (i.e.: piles or drilled piers) Information Courtesy of ESP Associates, P.A.

29 Highway Bridge Locations (continued) Profile along centerline of proposed bridge showing subsurface conditions based on data from surbsurface investigation Information Courtesy of ESP Associates, P.A.

30 SITE MITIGATION: Clean up of soil and groundwater contamination at petroleum storage and hazardous wastes sites Prevention of dam failure Design and implementation of slope stabilization methodologies Recommendations for ground improvement methodologies to allow construction on marginal sites

31 Environmental Geologist s Role: Define geology at the site Site Mitigation Project: KAFB Bulk Fuels Facility Identify types of contaminants Identify where they are in the ground Recommend ways to clean it up Photo from:

32 KAFB Bulk Fuels Facility (continued) Identify Contaminants found Hydrocarbons from Jet Fuel LNAPL - light non-aqueous phase liquid. Also called PSH phase separated hydrocarbon It floats on top of the water in the underground water table Contaminants in the LNAPL EDB - 1,2-dibromoethane/ethylene dibromide known carcinogen, can cause liver, stomach and nervous system problems Others

33 KAFB Bulk Fuels Facility (continued) Recommended ways to monitor and clean it up Install monitoring wells (ongoing since 1999) LNAPL Containment Well Installation (Dec 2011) LNAPL Treatment System Installation (Feb 2007, Spring 2012) Soil vapor extraction well and unit installation (2000, Spring 2012) may not work well for jet fuel Soil Excavation at source (Spring 2012) Natural Bioremediation feeding bacteria

34 SITE MITIGATION: Prevention of Dam Failure Engineering Geologist s Role: Determine modes of potential dam failure such as internal erosion, scour, overturning, sliding stability, earthquake loading, etc. Collaborate with engineers to determine the failure mechanism(s) and contribute to the design of mitigation measures. Install and monitor instrumentation within the dam to observe the performance of the dam over time..

35 . SITE MITIGATION: Design and Implementation of Rock Excavation Stabilization Methodologies The stability of rock excavations is typically governed by the structural geology of the rock in the slope area. Naturally occurring breaks such as bedding planes, joints, and faults may be collectively termed discontinuities = preferential planes of weakness through the stronger, intact rock mass. The most common discontinuities are joints and bedding planes. Stability failure tends to occur preferentially along these surfaces. Figure from Engineering Rock Mechanics An Introduction to the Principles, Hudson and Harrison, pg. 116.

36 Examples of Rock Excavation Stabilization

37 As you go throughout your week, think about the things you use that may have been influenced by a geologist. You might be surprised! To join AEG: Student membership is Free! Ask about our scholarships.