Terra Sana Consultants has qualified and trained staff, and cutting edge equipment to support groundwater investigations and studies.
Our services include:
- Collection of groundwater samples according to appropriate guidelines (i.e. water levels and water quality sampling) and routine reporting
- Developing monitoring plans and programs
- Preparation of investigation and monitoring reports
- Natural Attenuation Assessment
Our qualified scientists can design a monitoring program specific to your needs to assess the quality of your drinking water.
We provide advice on the laboratory tests required to assess drinking water quality specific to your settings, collect the water samples following relevant quality assurance protocols, organize laboratory testings and interpret the analytical results.
The importance of collecting robust data for future reference
Baseline assessments of water bores are required where production testing, production or mining has started on resource tenure.
Under Chapter 3 of the Water Act 2000 is required for a resource tenure holder to prepare a Baseline Assessment Plan (BAP) and to engage an independent, suitable qualified third-party to undertake a Baseline Assessment (BA) to all authorized water bores that could be potentially affected by the activities.
The information collected in the BA will establish the benchmark data required for future assessment of any possible impact on the bore and the base to negotiate the “make good agreements” with the landholders. Therefore, is very important the study is conducted as per high standard and best industry practice.
Which information is required to be collected as part as the Baseline Assessment?
Details about the minimum requirements for undertaking bore assessments are summarised in the Guideline Baseline assessments—ESR/2016/2005 (formerly EM1178) prepared by the Department of Environment and Science (DES). The main parameters required includes:
- Groundwater level;
- Free gas; and
- Water quality including field parameters and laboratory analytes.
What can go wrong?
Negative impacts on water quality may include increases in salinity and/or changes in major ion composition due to induced flow of water from underlying or overlying formations; and/or increases in the concentrations of dissolved gas associated with the depressurisation of coal seams.
The correct quantification of gases like methane in groundwater is challenging due to the tendency of the gas to separate from the water when the pressure decreases. An example of this effect can be experienced in everyday life when we open a bottle of a fizzy drink and we observe some of the gas leaving the container. When a groundwater sample is pumped from the aquifer to the surface the pressure decreases and like opening a fizzy drink some of the gas is lost. A portion of the gas is normally lost during the sampling due to the pressure differential between the groundwater and the surface.
The method outlined in the Guideline Baseline assessments to obtain gas samples is through the use of a flow-through cell (or gas separator/stripper) installed on the bore discharge pipework.
How can we help?
To collect accurate data of gas concentration in aquifer so crucial for a robust BA, Terra Sana Consultants (TSC) developed a field-portable gas-water separator. The sample of groundwater containing gases is captured in the main vessel of the separator connected to the outlet of the groundwater pump to avoid any loss of gas due during sampling. The gas –water separator can be connected to any commercial pump normally used for groundwater sampling. The equipment mimics and simplifies the laboratory process in the field, where a solution is sparged with an inert gas and the headspace is then collected in a summa canister or in a gas bag and sent to a NATA accredited laboratory for analysis. The gas -water separator can be used for the correct sampling, quantification, and characterization of any site where gas and generally Volatile Organic Compounds (VOCs) are present in an aquifer and require accurate quantification. This includes landfills, Coal Seam Gas (CSG) and mining sites.
TSC team includes qualified hydrogeologists, engineers and skilled field scientists experienced with the requirements of the resource industry and exploration projects.
With a portfolio of projects located in some of the most remote areas in Australia, Africa and Asia; TSC field team can deliver outstanding health and safety performance.
The focus on care and courtesy when accessing the landholder’s land has been crucial in developing a positive and collaborative relationship and progress the project in a timely manner.