Integrated Geophysics Safeguards Sogliano Solar Farm - IT
7 MW photovoltaic plant in Sogliano al Rubicone, Italy, faced significant landslide risks, particularly along its southern edge where active movements threatened the infrastructure. GGM.EARTH was engaged to conduct a comprehensive site characterization. Our integrated approach, combining advanced geophysical and geotechnical methods, provided critical insights into the subsurface conditions. This enabled the design of targeted mitigation measures, ensuring the solar farm's long-term stability, operational continuity, and substantial cost savings for the client.
“Precision geology for long‑term solar yield: explore the findings in our audio brief.”
Client: -
Location: Sogliano, Italy
Coordinates: 4874375m N°, 280643m E°
Technologies: DPSH, (SRT), MASW, HVSR, UAV LiDAR, 3D Model
Introduction
On the terraced slopes of Italy’s northern Apennines, a brand‑new 7 MW solar farm began to show early signs of shallow ground movement and water ponding after the first heavy rains. The owner asked GGM.EARTH for a clear diagnosis and a solution that would preserve the site layout.
Our approach
To understand exactly how the hillside behaved we combined several disciplines in a single field campaign:
super‑heavy DPSH soundings to 15 m to measure layer strength;
three seismic‑refraction lines plus one MASW profile to detect velocity changes and weak zones;
six HVSR points to pin down bedrock depth and local resonance;
UAV LiDAR at 5 cm resolution to capture micro‑topography.
All data were merged into one 3‑D subsurface model.
What we found
The model revealed a 1–2 m‑deep slip surface on the south side and a moisture‑rich clay wedge below string #7, exactly where low seismic velocities coincided with low DPSH strength.
Why it matters
Knowing the precise geometry of the landslide allowed us to design a drainage system that is surgical rather than over‑built, reducing earthworks, avoiding interference with cables and keeping investment lean while protecting long‑term production.
Next Steps — from one project to portfolio value
Once the drainage layout is installed, the plant will move into a far more predictable operating phase: stable modules, schedulable maintenance and a certified risk file that supports future financing. Most importantly, data from this site feed our library of dozens of similar hillside‑PV surveys, sharpening design factors for every project that follows and aligning with our Environmental and Sustainability Practices commitment.
Solar‑Farm GeoRisk Suite
GeoRisk Audit – integrated geotechnical, geophysical and LiDAR survey delivering a single 3‑D subsurface model.
Drainage & Slope Design – mitigation layout engineered for safety, constructability and cost efficiency.
Digital Twin & Monitoring – optional GNSS/MEMS sensor network streaming live slope‑health data to an online dashboard.
Explore the full service portfolio: https://www.ggm.earth/services
Technical data at a glance
DPSH: 6 boreholes, 15 m, mechanical logs correlated with Vs and resistivity
Seismic refraction: 3 lines, five seismic layers mapped
MASW + HVSR: Vs30 profile and resonance frequencies established
UAV LiDAR DEM: 5 cm resolution, high‑precision drainage modelling
Slip surface depth: 1–2 m along the southern edge
Drainage design: Ø200 mm perforated pipes at 3 % grade; expected pore‑pressure drop ≈ 68 %
Safety factor: raised from 0.94 to 1.35 after mitigation
Video summary: 20‑second field recap
These figures join our growing data set from over forty hillside solar farms, continuously improving design accuracy and reliability for future clients.
“Precision geology for long‑term solar yield: explore the findings in our audio brief.”
