Hydrogeology

HYDROGEOLOGY

Throughout the six decades of operation, PELA’s primary focus of expertise has been hydrogeology – the science that deals with subsurface waters and related geologic aspects of surface waters. Our staff includes hydrogeologists who have studied groundwater and surface water hydrogeology throughout the United States and a number of foreign nations. Site settings range from unconsolidated deposits to karstic environments, and complex folded and faulted carbonate rock. Understanding the hydrogeologic regime is key to various aspects of environmental projects and PELA’s hydrogeologists and other professionals have the technical expertise and are experienced in the methods and theories needed in performing such projects as:

SURFACE WATER AND WATERSHEDS

The continued migration of people and businesses from urban centers to suburban and rural areas, with the resulting conversion and development of forest and farmlands to residential and commercial structures, has made watershed management more necessary and complex than ever before.

PELA’s professional staff has decades of experience collecting and analyzing stream and watershed information. This experience includes:

• The design, construction and instrumentation of surface-water gages and monitoring stations
• Sampling and surface-water characterization
• Stream gaging (discharge measurements)
• Development of rating curves
• Statistical analysis of hydraulic data
• Flood plain mapping/flood studies
• Stream and flood plain geomorphology
• Basin (watershed) analysis and modeling
• Evaluation of point- and nonpoint-source contaminants
• Investigation, design, and implementation of erosion control measures
• Land use assessment
• Watershed management planning and policy development
• Litigation support and expert testimony

WATER SUPPLY

PELA’s project experience in water supply spans decades and the world including studies in the US, the Middle East and Far East, South America, and the African continent. Project experience includes hydrogeological methods to locate and survey existing water resources, perform pumping tests and watershed/reservoir analysis, and complete water quality evaluations.

Our staff has completed water supply projects including:

GEOPHYSICAL INVESTIGATIONS

PELA applies one or more geophysical methods to rapidly collect data for site characterization. Geophysical techniques are noninvasive investigative tools. Investigation results are typically integrated with geologic and hydrologic data to formulate interpretation of site conditions. We employ:

• Electrical resistivity tomography (ERT), seismic, and magnetometer surveys
• Spontaneous potential surveys
• Ground penetrating radar surveys
• Down-hole geophysical logging
• Including resistivity, potential, caliper, natural gamma, and temperature
• Down-hole camera and acoustic televiewer

Examples of application of geophysical data: