EXPERT REPORT CONCERNING GEOLOGIC AND HYDROGEOLOGIC ASPECTS OF TETRA4’S CLUSTER 2 VIRGINIA GAS PRODUCTION PROJECT, VIRGINIA, FREE STATE PROVINCE, SOUTH AFRICA

The review identifies fundamental flaws in the site characterization, aquifer testing, and numerical modeling of the Cluster 2 Virginia Gas Production Project, concluding that the assessment does not provide a reliable basis for decision-making.

• The geophysical survey methodology was flawed because the seven traverses were oriented parallel to the target lineament, which is inconsistent with standard practices for investigating lineaments.
• The drilling program was insufficient for the 187,000 ha area, with only five new boreholes drilled, only three of which intersected water strikes and two of which intersected intrusive dolerite rocks.
• The interpretation of aquifer testing data lacked justification, as the report failed to specify the aquifer type or explain why specific analytical solutions—such as Theis, Neuman, and Walton's methods—were selected.
• The numerical model's representation of rivers as constant head boundaries is potentially inaccurate because it neglects possible infiltration zones along the river course.
• The model includes a 30-metre-thick dolerite sill throughout the site domain without providing borehole logs or fieldwork to substantiate its pervasiveness, which significantly impacts predictions of contaminant migration.
• The transport modeling is inadequate because it omits diffusion coefficients and fails to use multiphase models necessary for simulating the migration of methane as both dissolved and free gas phases.
• Model calibration confidence is low because up to 75% of recorded water levels may represent dynamic conditions rather than natural static conditions, and there was a 21.63-metre difference between simulated and observed water levels for borehole RTBH10.

APA

de Lange, F., & Lukas, A. (2025). EXPERT REPORT CONCERNING GEOLOGIC AND HYDROGEOLOGIC ASPECTS OF TETRA4’S CLUSTER 2 VIRGINIA GAS PRODUCTION PROJECT, VIRGINIA, FREE STATE PROVINCE, SOUTH AFRICA. Centre for Environmental Rights. https://cer.org.za/wp-content/uploads/2026/04/Expert-report_Tetra4_de-Lange_10122025_rev1.pdf?x21779

Chicago

de Lange, F, and A. Lukas. EXPERT REPORT CONCERNING GEOLOGIC AND HYDROGEOLOGIC ASPECTS OF TETRA4’S CLUSTER 2 VIRGINIA GAS PRODUCTION PROJECT, VIRGINIA, FREE STATE PROVINCE, SOUTH AFRICA. Centre for Environmental Rights, 2025. https://cer.org.za/wp-content/uploads/2026/04/Expert-report_Tetra4_de-Lange_10122025_rev1.pdf?x21779.

Wikipedia

{{cite report |last1=de Lange |first1=F |last2=Lukas |first2=A. |title=EXPERT REPORT CONCERNING GEOLOGIC AND HYDROGEOLOGIC ASPECTS OF TETRA4’S CLUSTER 2 VIRGINIA GAS PRODUCTION PROJECT, VIRGINIA, FREE STATE PROVINCE, SOUTH AFRICA |publisher=Centre for Environmental Rights |date=October 2025 |url=https://cer.org.za/wp-content/uploads/2026/04/Expert-report_Tetra4_de-Lange_10122025_rev1.pdf?x21779 |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{delange2025expert, author = {de Lange, F and Lukas, A.}, title = {{EXPERT REPORT CONCERNING GEOLOGIC AND HYDROGEOLOGIC ASPECTS OF TETRA4’S CLUSTER 2 VIRGINIA GAS PRODUCTION PROJECT, VIRGINIA, FREE STATE PROVINCE, SOUTH AFRICA}}, institution = {Centre for Environmental Rights}, year = {2025}, month = oct, url = {https://cer.org.za/wp-content/uploads/2026/04/Expert-report_Tetra4_de-Lange_10122025_rev1.pdf?x21779}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }