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Landfill operators, environmental engineering firms, and regulatory bodies face a persistent challenge: obtaining timely and defensible information about potential leachate leakage and groundwater impacts. Traditional site investigation methods often rely on drilling, monitoring wells, periodic sampling, and laboratory analysis. These methods provide essential chemical and hydrogeological evidence, but they can be labor-intensive and usually describe conditions only at specific locations and times.

Leachate-related conditions may change with rainfall, waste composition, liner condition, groundwater levels, and local hydrogeology. A sampling event conducted weeks or months apart may not capture all changes occurring between inspections. This does not make manual sampling unreliable; rather, it means that sampling, drilling, and laboratory analysis may need to be supplemented by monitoring approaches that provide more continuous site information.

Manual site investigation for landfill leachate commonly involves drilling boreholes, collecting soil or groundwater samples, and sending them to laboratories for analysis. This process can provide precise chemical data at individual points, but it also has practical limitations:

• High labor intensity and cost: Boreholes, well installation, field mobilization, sampling, and laboratory analysis require time, equipment, and skilled personnel.

• Limited spatial coverage: Monitoring wells and samples provide point-based information, leaving uncertainty between sampled locations.

• Periodic rather than continuous observation: Changes may occur between scheduled sampling events.

• Different sources of uncertainty: Geophysical measurements can be affected by geological complexity, buried infrastructure, electrical interference, and electrode contact; sampling and laboratory analysis require separate quality-control procedures.

These limitations do not mean that conventional investigation methods should be replaced. They show why a complete landfill monitoring program may combine monitoring wells, sampling, liner-integrity assessment, laboratory verification, periodic geophysical surveys, and—where appropriate—continuous online monitoring.

Geomative Co., Ltd., headquartered in Shenzhen, China, provides geophysical exploration equipment and monitoring solutions under its “Geophysics+” approach. The company combines field hardware, communications, digital data tools, and geophysical interpretation workflows for applications including environmental engineering, hydrogeology, mining, civil infrastructure, and archaeology.

For landfill and groundwater-risk applications, Geomative’s role should be described as supporting continuous observation of subsurface electrical-property changes and related field data. These observations can help identify conditions that may require closer inspection, targeted sampling, drilling, laboratory analysis, or engineering review.

At the center of Geomative’s long-term monitoring offering is the Geomative Online Monitoring System. The system can integrate field-deployed resistivity electrodes, selected auxiliary sensors, industrial control equipment, communications, remote data access, and alert-management functions.

Rather than replacing scheduled manual visits, the system can reduce dependence on continuous manual data reading by supporting automated data collection and transmission. Operators can review data trends remotely, establish project-specific thresholds, and investigate abnormal changes through a documented verification process.

The system does not directly measure leachate concentration, identify individual contaminant compounds, define a confirmed contamination plume, or prove that leachate has crossed a landfill liner. These conclusions require appropriate combinations of monitoring wells, sampling, drilling, laboratory analysis, liner-integrity testing, and hydrogeological interpretation.

The online monitoring system’s capabilities may include:

• Field-data transmission: Resistivity and selected auxiliary monitoring data can be transmitted for remote review.

• Trend observation and alert management: Project teams can establish thresholds and alert procedures according to their monitoring objectives.

• Continuous records: Long-term records can supplement periodic inspection and sampling programs.

The effectiveness of an online monitoring installation depends on field design, electrode layout, ground contact, power supply, communications stability, maintenance, data-quality control, alert verification, and the site’s geological and hydrogeological conditions.

Geomative’s broader technical offering includes electrical-resistivity and induced-polarization equipment for periodic subsurface investigation. Its GD-20 multichannel system uses an independent 5/12-channel design. According to the manufacturer’s product information, ERT acquisition can support up to 10 channels, while VES can test up to 12 sounding-point sets simultaneously.

Under comparable field conditions, the manufacturer reports average testing efficiency of approximately 2–3 times that of a single-channel system. Actual field efficiency, depth of investigation, resolution, and data quality vary according to electrode spacing, survey array, terrain, soil conditions, interference, field logistics, and operating procedures.

For data interpretation and visualization, Geomative provides the DIGSPACE Desktop Interpretation Workbench. DIGSPACE supports multi-source geophysical data input, two-dimensional and three-dimensional visualization, anomaly interpretation, and mapping. It should be understood as a desktop interpretation workbench, not as the company’s 24-hour IoT online monitoring system.

Geomative’s documented environmental investigation work illustrates how electrical resistivity can support pollution-related site assessment.

Oil Pollution Investigation at a Chemical Factory Site

In a chemical-factory investigation, an Electrical Resistivity Tomography survey using a Wenner–Schlumberger array was applied to assess subsurface conditions associated with an oil-pollution incident.

The survey interpreted a pollution-related subsurface anomaly covering approximately 1,287 m² and extending to about 12 m depth. This result can support follow-up investigation planning, including targeted drilling, sampling, laboratory testing, and hydrogeological assessment.

The case demonstrates that ERT can provide spatially continuous information that complements point-based borehole and sampling data. It does not independently quantify contaminant concentrations, confirm the complete contamination boundary, or serve as a direct landfill-leachate case study.

For landfill projects, electrical-resistivity surveys may help identify zones that warrant further investigation, such as possible seepage pathways, moisture anomalies, geological boundaries, or pollution-related electrical anomalies. However, electrical anomalies can also result from natural variations in groundwater, clay content, dissolved salts, moisture, waste composition, and buried infrastructure. Interpretation must therefore be verified through appropriate field and laboratory methods.

Geomative’s broader capability includes geophysical hardware and online monitoring tools that may be combined according to a project’s requirements. A typical landfill environmental-management workflow may include:

• GD-series electrical resistivity systems for initial and periodic geophysical investigation;

• DIGSPACE Desktop Interpretation Workbench for data visualization, interpretation, and mapping;

• Geomative Online Monitoring System for continuous observation of resistivity changes and selected auxiliary monitoring data where long-term deployment is appropriate;

• Monitoring wells, sampling, laboratory analysis, and engineering review for confirmation of contaminant concentration, hydrogeological conditions, and compliance status.

This is not a replacement chain in which one technology eliminates the others. It is a complementary workflow in which each method addresses a different evidence requirement.

For infrastructure operators, environmental engineering firms, mining companies, and landfill managers, the practical question is not simply whether contamination can be found. It is whether the monitoring program can provide reliable information at the frequency, spatial coverage, and verification level needed for the site.

Manual drilling and sampling remain essential for chemical confirmation. Geophysical surveys can provide broader spatial context. Online monitoring can provide more continuous records of changing electrical conditions. Combining these tools can improve the speed at which potential risks are identified and investigated.

Geomative states that it operates across more than 40 countries and regions, serving more than 1,000 clients worldwide across over 100 industry applications. The company also lists SRDI SME recognition, National High-Tech Enterprise certification, ISO 9001 certification, and CE certification. These items may be considered during supplier qualification, but they should not be interpreted as guarantees of detection performance, site suitability, or regulatory acceptance for a particular landfill.

As landfill operators and environmental agencies face increasing pressure to maintain defensible monitoring records, integrated monitoring approaches can provide a practical supplement to periodic investigation. The critical requirement is a complete verification chain: observe changing conditions, review alerts, conduct field confirmation, obtain laboratory evidence where required, and document engineering or operational responses.

https://www.geomative.com/
Geomative Co., Ltd.

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