CHILE (REUTERS) - Chile's Atacama desert is one of the driest places on earth, but home to an abundance of high-grade lithium deposits, existing in brine pools in the desert.

Lithium is big business - serving as a key component for most electronics like mobiles and laptops. That makes the Atacama attractive to miners.

United States-based miners Albemarle and Chile's SQM celebrated deals with the Chilean government earlier this year, allowing them to increase lithium output. But the firms accuse each other of drawing more brine than allowed, which could affect future production in the area.

Geologists are concerned, as the arguing shows neither side knows exactly how much brine is left as production ramps up.

"The data presented by the companies in their framework are, in my technical opinion, not sufficient to give guarantees that we aren't going through a water crisis or that it could run out suddenly. We don't really know," said hydro-geologist Mariana Cervetto.

Albemarle's chief executive officer denies overdrawing brine. SQM also says "environmental sustainability isn't compromised by their operations". But for local indigenous communities and geologists, questions still remain.

President of the Council of Peoples from Atacama Manuel Salvatierra said: "I believe the necessary safeguards have not been taken to prevent exploitation of this basin, where the extraction of natural resources has been allowed, without our consent and without knowing this territory."

Chile's state development agency Corfo also raised questions about the availability of water in the Atacama. They found more water and brine was leaving the ecosystem through pumping and evaporation than was coming back in through rain and snowfall. But the study could not pinpoint which of the miners were to blame for the imbalance.

The report has forced regulators to prepare new rules to restrict extraction.