Savannah Resources has started the final pre-construction drilling programme at its Barroso Lithium Project in northern Portugal, moving the development into another phase of geotechnical and groundwater investigation before detailed engineering is frozen for key site infrastructure. The programme is expected to run for about four weeks and is intended to reduce uncertainty around reservoirs, tailings storage, waste dumps, roads, and bulk earthworks.
Two rigs are already operating at Barroso. A diamond rig is carrying out geotechnical investigation, while a down-hole hammer percussion rig is being used to install water piezometers. Savannah expects a third rig to arrive shortly to increase the pace of geotechnical work, followed later in September by a fourth reverse-circulation rig.
The work is not primarily an exploration campaign aimed at enlarging the lithium resource. Data from the holes will feed into the geotechnical study used for final detailed engineering, while the monitoring bores will provide groundwater information before, during, and after construction and operation. That distinction matters because the project has moved beyond proving that lithium-bearing pegmatites are present and into the engineering required to build safely around them.
Ground conditions can alter the cost and design of a mine even where the orebody is already well defined. Foundation behaviour, slope stability, groundwater movement, rock strength, drainage, and the availability of suitable construction material all influence civil works. At Barroso, those questions extend across the process plant, water infrastructure, roads, waste facilities, and tailings storage system rather than sitting within the open pits alone.
Savannah published the Phase 1 Definitive Feasibility Study in July together with an initial 20 million-tonne JORC Ore Reserve. The study envisages mining about 1.5 million tonnes of run-of-mine ore annually and producing an average of roughly 183,000 tonnes a year of dry spodumene concentrate grading around 5.5% Li2O. First concentrate is scheduled for November 2028 under the current project plan.
The latest fieldwork is designed to move that feasibility-level design towards execution. Savannah says detailed engineering of the water reservoirs is well advanced, while the vendor for front-end engineering design of the process plant has been selected and FEED is expected to start this week. Technical and environmental and social due diligence for project finance is also progressing, with reports being prepared for shortlisted potential lenders.
The financing work is increasingly tied to engineering maturity rather than headline resource size. Lenders and contractors need to know whether earthworks quantities, foundations, water systems, tailings structures, access routes, power infrastructure, and process-plant interfaces are sufficiently defined to support cost estimates and contract packages. Geotechnical uncertainty left unresolved until construction usually reappears as contingency, delay, or both.
The project schedule published in the DFS assumes approximately 22 months from the start of construction on the North Access Road to first concentrate. The critical path runs through power lines and the substation, process-plant energisation, and commissioning, while the Boticas bypass road is not currently treated as critical to first production because existing roads can be used to reach the A24 motorway.
Water and tailings design also carry a disproportionate share of execution risk. The DFS uses a dry-stacked tailings storage facility with filtered tailings rather than conventional slurry deposition, reducing the amount of free water stored within the facility but increasing the importance of compaction, drainage, material handling, and progressive embankment construction. Additional drilling and monitoring data are therefore directly relevant to the assumptions used in the feasibility design.
Barroso has strategic status under the European Union’s Critical Raw Materials Act and was approved for a Portuguese state development grant of up to €110 million in January. The project is intended to provide a domestic source of spodumene concentrate into Europe’s battery-material supply chain at a time when the region remains heavily dependent on imported lithium raw materials.
Strategic designation does not remove the remaining permitting and construction sequence. Savannah still needs to complete the RECAPE process and secure the corresponding environmental-conformity decision before construction can proceed through the remaining approvals. Detailed engineering, financing, procurement, land access, and contractor mobilisation have to advance in parallel if the current 2028 production timetable is to hold.
Land access has already affected field activity. Work resumed in June after the Portuguese state responded to a precautionary legal measure concerning temporary access, and later activity was interrupted by forest-fire restrictions. Savannah has since signed further access and benefit-sharing agreements, including arrangements covering another 150 hectares, while continuing to acquire additional plots needed for the project.
The latest drill programme is therefore a relatively small field operation with a large effect on the quality of the project definition. Its purpose is to replace assumptions with site-specific data before civil quantities, water-management systems, and major infrastructure are committed to detailed design. Barroso is no longer being judged mainly on whether it contains enough lithium; the harder questions now concern whether the mine, plant, roads, power, water, and tailings systems can be built to the cost and schedule set out in the DFS.
