Ground gas measurements are influenced by a myriad of factors – the underlying gassing activity, subsurface migration conditions, meteorological and tidal factors, and the status of the monitoring well itself. Here’s Why Measuring Water Levels is Crucial for Understanding Ground-Gas Behaviour:
As surely as the weather invariably permeates our social conversations, weather conditions also affect each of these influences:
Water penetration and saturation in the soil is critical to microbial or leaching conditions that produce gases; lateral water movement will drive or inhibit gas fluxing behaviour through the ground; water ingress/egress in monitoring wells will change the void head-space volume, producing pressure differentials which will affect the gas composition and may induce flows by a piston effect.
Even more detrimentally, the monitoring wells may become swamped such that the perforated sections are below the water level, hence rendering the monitoring well as non-representative due to gases measured being those of a stagnant head-space.
Furthermore, elevated water levels are conducive to gas dissolution and evaporation, introducing further uncertainty in the gas head-space measurements given the omission of gas levels dissolved in the ground-water.
In this way, the representativeness of the gas measure can be confirmed – better again, it can be confirmed in near real-time, allowing corrective actions to be taken as necessary – pumping out or recommissioning a swamped well, investigate water (typically aligned with gas) migration pathways and rapid diagnosis of gas measurements with respect to internal (i.e. organic off-gassing) or external (e.g. weather) conditions.
At AmbiSense we believe that environmental and process monitoring is best served by reliable, cost effective, field-deployable, smart instruments capable of providing a continuous flow of accurate data and accessible to customers on any device. Our innovative instruments are specifically designed for long-term deployment in harsh operating environments enabling customers to maximise their return on investment. Contact us today to find out how we can help you or try our Live Demo.
What’s your view and experience with integrating water levels with gas monitoring? Tell us in the comments below.
Ground gas measurements are influenced by a myriad of factors – the underlying gassing activity, subsurface migration conditions, meteorological and[...]