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June 26-27, 2001
Richmond, Virginia

Potential Science Plan Design for Ground-Water Investigations in the Piedmont/Blue Ridge Region

The following list of ground-water issues and activities was compiled during a brainstorming session at the workshop to aid in the formulation of a science plan for ground-water investigations in the Piedmont/Blue Ridge region. The topics are color coded to indicate whether the future investigation will be part of a regional synthesis or integrated into issue-based research project. These designations will be revised as the plan is developed.

Key	Scale/Type of Investigation
	Regional
	Issue based
	Mixed

Ground-Water Topics, Issues, and Activities

Topic	Issue	Research Questions	Possible Activity
Hydrogeologic Framework	Fractures	How do fractures control ground-water flow in the region?	Fracture orientations vs. geology/rock types Quantitative testing?
	Aquifers	What is an aquifer in the Piedmont/Blue Ridge region? How are aquifers/confining units defined? How transferable are the data? How are local differences reconciled on a regional scale?	Depends upon scale. Water-bearing zones may be more relevant. Begin with test of existing conceptual models Relate regional geology and hydrogeology by subdividing on meaningful properties (structure, foliation, rock types, etc.) Statistical/Probabilistic approach Well yield/specific capacity Deep ground water
	Saprolite	What is the role of saprolite in ground-water-flow systems of the region?	Map saprolite thickness & characteristics (regional) by defining settings & types and identifying distribution Physical & chemical properties Some generalizations possible Transition zones Analyze spatial relations (hydrologic vs. geologic characteristics)
Water Budget	Recharge	Can ground-water recharge be quantified? How ground-water and surface-water interact?	Hydrograph separation techniques (APRASA, Chesapeake Bay, ACF Basin) Climate budget (Thornthwaite) Deep percolation model Remote sensing Ground-water levels (seasonal distribution) - Continuous record Correlation to partial record sites Base-flow variability index (APRASA)
Water Budget	Withdrawals	What is the distribution of water use in the region?	Compile existing water use to determine quantity, source type, purpose (agriculture, municipal, etc.), and future projections Land use (transition from rural to urban) Classify areas in terms of stressed vs. unstressed conditions Long-term data needed Declining yields over time Conjunctive use
Ground-water levels	Drought Conditions	How are ground-water levels affected by droughts?	Establish real-time network for region Analyze depth to water and well setting Use ground-water dating techniques to determine mixing ratios Long-term monitoring needed
Ground-water levels	Ground-water flow systems	What do ground-water levels tell us about flow systems (local vs. regional)?
Sustainability/ Vulnerability/ Susceptibility	Source Water Assessment	How to protect and preserve ground-water resources in the region?	Flow path studies Compilation of ground-water dating studies Geophysical approach Capture area delineation Aquifer sensitivity
Sustainability/ Vulnerability/ Susceptibility	Wellhead Protection	What is a capture area in fractured rock?
Water Quality	Radionuclides	Where are the radionuclides in ground water the highest?	Compile existing data on uranium, radium, radon, etc.
	Bacteria	Are certain settings more susceptible to bacteria contamination?	Compile systems classified as ground water under the influence of surface water
	Emerging Contaminants	Where and how are emerging contaminants affecting ground-water quality?	Identify activities currently addressing these contaminants (Toxic Substances Hydrology Program, National Water-Quality Assessment (NAWQA) Program)
	Monitoring	What are the long-term trends in the quality of ground water?	Long-term monitoring needed


Contact: dlnelms@usgs.gov U.S. Department of Interior, U.S. Geological Survey Privacy Statement Disclaimer URL: http://va.water.usgs.gov/PiedWkshop/approach.htm Last modified: 03 Aug 2001 09:16:46 AM