"I don't want them to take away what has been left to me by my parents and grandparents," 55-year-old Loureiro said. "I don't want the mine ... I will fight it to the death."

She is among local activists in Portugal and elsewhere whose determination to halt mine developments - via protests, legal challenges or simply refusing to sell or rent the land needed - threatens to slow the European Union's green transition.

Their opposition could also frustrate plans for the EU to reduce its dependence on China by producing more itself of the raw materials needed for technology like EVs.

With 60,000 tonnes of known reserves, Portugal is already Europe's biggest producer of lithium, traditionally mined for ceramics. Barroso, whose lush mountain pastures are a Food and Agriculture Organization heritage site, contains one of its richest deposits.

London-based Savannah Resources (SAVS.L) wants to build four open-pit mines there, producing enough lithium each year for around half a million EV batteries.

"All eyes are on a project like this," Martin Jackson​​​​, head of battery raw materials at consultancy CRU, said of Savannah's plans, which got a favourable assessment from Portugal's APA environment agency in May.

"It is a key test for Portugal and Europe as a whole."

The European Commission's planned Critical Raw Materials Act would see the EU mine at least 10% of the lithium, cobalt and similar materials it uses by 2030 and refine and recycle more as global competition grows for those resources.

Michael Schmidt, senior analyst at Germany's DERA mineral resources agency said current and planned mining projects could cover 25-35% of EU lithium demand by 2030, although meeting the 10% target for materials like nickel and cobalt would be harder.

Referring to the Barroso project and another in France, he said it would be "a disaster if either ... doesn't succeed".

"While Europe would be able to procure the minerals elsewhere, what would be the costs? Suppliers would be able to dictate prices and conditions," Schmidt said.

Portugal's lithium reserves have "an important role to play" in meeting the EU's target, the environment ministry said, adding that new mines would bring money and jobs for local communities. In a statement, it also pledged "the highest social and environmental standards".

But Barroso farmer Nelson Gomes, 47, part of the UDCB movement campaigning against mining expansion, is sceptical.

"They (governments) are trying to clean up cities by polluting villages," he said.

"COLONIALISM"

Opposition to mining projects elsewhere in Europe has also focused on environmental damage.

Last month, climate activist Greta Thunberg protested against plans to develop a huge rare earth metals deposit at Kiruna, in Sweden's far north, which the area's indigenous Sami people have decried as "colonialism".

"Are we to be sacrificed so that people in big cities can have electric cars?," Sami community representative Karin Kvarfordt Niia said.

State-owned miner LKAB's spokesperson Anders Lindberg said it could minimise the effects on the Sami, who without new mines to hasten electrification would face threats from accelerated climate change to their traditional way of life.

Savannah described as a "major milestone" the APA's green light in May for its Barroso project, subject to conditions regarding the removal of vegetation and use of river water.

Last week, APA also approved a new mine in nearby Montalegre for local operator Lusorecursos.

But with only 15 of 916 submissions in a public consultation supporting the project, Savannah faces a struggle to win over locals who have said they will fight it and the APA in court. The company, which aims to start production at Barroso in 2026, has earmarked $40 million for community projects and stressed other benefits including a new road.

"It's like they are telling us that they're going to cut off one of our arms or legs and then offer one of the best doctors in the world to heal us," said UDCB's Catarina Alves Scarrott.

Savannah expects to pay about 15 million euros ($16 million) to secure the 840 hectares it needs, about 75% of which is traditional "baldios", or common land.

It is offering an annual 335 euros per hectare to rent the baldios and 2-2.5 euros per square metre to buy private plots – at least twice their market value, according to Scarrott and Savannah. So far it has secured just 93 hectares.

"Most of the population ... will not accept any money because people know what is at stake: their home," said Aida Fernandes, head of Barroso's baldios association, which has rejected the company's offer.

Savannah's CEO Dale Ferguson told Reuters the land issue is "certainly something we need to resolve ... via dialogue" but that the process was going well.

Ferguson - who will be succeeded this month by Portuguese Emanuel Proenca - said a 30-year mining lease "safeguards Savannah's access" to the necessary land, and that it "will use the mechanisms provided in Portuguese law but only when it is not possible to reach an agreement".

The Portuguese government could authorise a compulsory purchase in the public interest but no such request has been received, the environment ministry said, noting that such an order would require the payment of fair compensation.

EUROPE-WIDE

An annual camp-out against the mine organised by UDCB in August brought together locals and more than 200 activists from Portugal and countries including France and lithium-rich Chile.

Shouting "Barroso is not for sale" and "Savannah, get off our mountains", they marched around the village of Covas with its rustic stone houses. Some carried animal skulls to highlight what they say are threats to the region's fauna.

"This is a Europe-wide problem, as multinationals dig all over the continent," said Teresa Camille, 54, whose group Stop Mine 03 is campaigning against plans for a mine in France that could supply lithium for around 700,000 EV batteries a year.

Gunilla Hogberg Bjorck, who represents opponents of southern Sweden's Norra Karr rare earths project, held up since 2009 by concerns it could pollute drinking water, fears the EU's push for mining independence will be a "catastrophe" for environmental law.

"Politicians listen to those who shout loudest and have most money - and that's the mining industry," she said.

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