The use of sophisticated computers, data loggers and solid-state sensors have only recently evolved into a commonly used technique for data collection during environmental investigations. However, Terran Corporation personnel have been designing, constructing and installing instrumentation for collecting chemical and physical data at remote, sometimes inclement project sites for over ten years. Although the purposes of the project requiring remote data acquisition may differ, each installation has the common elements of collecting and storing real-time data from in-situ sensors for retrieval and transfer to a central processing location. These functions occur with minimal opportunity for data entry error.
There are many applications for remote acquisition of environmental data, including:
- Long-term Monitoring
- Continuous Monitoring
- Episodic Monitoring
- Sentinel Monitoring
When data must be collected for long periods of time in remote locations, problems arise in maintaining sufficient power and adequate data storage space. Long-term monitoring typically requires low power CMOS based data loggers connected to non-fouling sensors. Real-time data is collected, averaged for a fixed interval and stored on-site for later retrieval. Terran designed, built, installed and maintained a system to record seasonal variability of specific conductance, pH, redox, flow, rainfall and humidity measurements in several man-made wetlands used to abate acid mine drainage.
Continuous monitoring requires data to be reported in real-time or near real-time, usually in raw form for immediate processing at a central computer. Terran designed and installed a network to continuously monitor the capture zone of a pump and treat system. The system utilized over twenty monitoring wells distributed over 400 acres, and was used for the protection of a municipal water supply.
Many environmental investigations require random events to be documented. For example, rainfall above a predetermined amount may trigger the collection of stormwater runoff samples. Terran Corporation owns and maintains portable data acquisition systems to record episodic changes in water levels, water discharge and meteorological conditions.
Sentinel monitoring allows unintended events (spills, releases) to be detected prior to loss of control. Terran personnel designed, assembled and installed an early warning system using radio telemetry to monitor the water level of an industrial sewer to prevent the unauthorized release into an adjacent river.