SANTIAGO (Reuters) - Chile's environmental regulator on Thursday said it filed two charges against state copper giant Codelco over the management of its Talabre tailings dam at its Ministro Hales division in northern Chile.

The charges were for the lack of a contingency plan to avoid affecting underground water, and for the incorrect deposit of tailings materials dating to 2017.

The company, the world's biggest copper miner, has ten days to submit a compliance plan and an additional five days to appeal, and could face a fine of about 8 billion pesos ($8.71 million).

Tailings dams are embankments constructed near mines to store waste in a liquid or solid form, and are subject to strict environmental standards to prevent collapses and contamination of surrounding communities and natural resources.

Codelco, which investing in electric buses, cactus nurseries and recycling as part of a drive to reduce environmental impacts, said it would work quickly to address the matter.

"We completely understand the concern this situation causes, and we will be exhaustive in detailing the plans we have developed and will deploy to comply with our obligations," Codelco said in response to questions from Reuters.

"We hope to overcome this situation as soon as possible and, if shortcomings are identified, to correct them as soon as possible."

The SMA labeled the charges as "serious," which ranks as the second of three levels of offenses. It said they stem from a citizen complaint last year alleging seepage from the tailings dam since 2019, which could affect the Rio Loa aquifer, as well as potentially flow towards the city of Calama and the Yalquincha aquifer.

The Talabre dam processes mining waste from Codelco's Ministro Hales, Chuquicamata and Radomiro Tomic divisions.

Prior to the complaint, the Superintendency of the Environment (SMA), had last inspected the site in 2017. It did further analysis last year.

"The Superintendency formulated two charges against Codelco ... after finding the miner did not take environmental measures related to the Talabre dam," the SMA said in a statement.

Codelco last year requested an environmental permit to extend the useful life of its Ministro Hales mine by 30 years with a $2.5 billion investment.

($1 = 918.3200 Chilean pesos)