Specialty Environmental Services
Aquifer Pump and Slug Testing
CRG performs aquifer pump and slug testing to assist environmental scientists in determining fate and transport, groundwater recovery radius of influence, and groundwater flow characteristics used in groundwater remediation.
A pumping test is a controlled field experiment in which a well is pumped at a controlled rate and water-level response (drawdown) is measured in one or more surrounding observation wells and optionally in the pumped well (control well) itself. The goal of a pumping test, as in any aquifer test, is to estimate hydraulic properties of an aquifer system. For the pumped aquifer, one seeks to determine transmissivity, hydraulic conductivity (horizontal and vertical) and storativity (storage coefficient). In layered systems, one also uses pumping tests to estimate the properties of aquitards (vertical hydraulic conductivity and specific storage). Pumping tests can identify and locate recharge and no-flow boundaries that may limit the lateral extent of aquifers as well.
A slug test is a controlled field experiment in which the water level in a control well is caused to change (rise or fall) instantaneously and the subsequent water-level response (displacement from static) is measured in the control well and one or more surrounding observation wells through time. The goal of a slug test, as in any aquifer test, is to estimate hydraulic properties of an aquifer system such as hydraulic conductivity.
Magnetometer and Ground Penetrating Radar (GPR) Surveys
CRG performs magnetometer and GPR surveys to aid in locating buried vessels for removal from the subsurface. A magnetometer can give insight into what lies beneath the soil. It indicates the best places to dig for buried tanks, piping, pipelines, drums, and other metallic vessels that may contain petroleum or hazardous chemicals.
CRG Provides GPS data collection services to assist environmental scientists in obtaining accurate field measurements and elevations needed for mapping and assessment applications.
Global Positioning Systems (GPS) allows accurate navigation, positioning and recording of features which are very useful for archaeology. A GPS instrument uses a series of satellites and base stations to provide accurate sub-meter locations. GPS surveys can be used to set-out pre-designed test trenches or area excavations as well as mapping the location of field boundaries, buildings etc. Natural and built heritage mapping can also be achieved as well as the recording of excavated features such as open test trenches and excavation areas.
Off Road and Difficult Access Sampling
CRG Texas accesses some of the most difficult areas using off-road 4 wheel drives, swamp buggies, and pontoon or air boats for environmental and ecological assessments. Our safety standards are the highest in the industry surrounding employee and public safety and sample and data collection quality second to none in the industry.
Additional Specialty Services
CRG Texas provides the following additional field services:
- Well development and discreet groundwater sampling
- Product recovery and abatement
- Industrial cleaning – vacuum truck, line jetting, power washing services
- Spill cleanup, release determination, and delineation