The biggest foreign shale driller in the US just took a $7B hit

Australia’s BHP Billiton Plc announced Friday it would write off $7.2 billion in valuation of its U.S. operations.

Citing “significant volatility and much weaker prices," the company only will have five oil drilling rigs in operation stateside, down from 26 last year, according to Fortune.

Like other mining companies, BHP faces a drought of demand for its chief product – iron ore – due to China’s stifled economy, but hasn’t scaled back production.

Legal issues also are looming in BHP’s future after a wastewater dam in a Brazilian mine burst in December, causing the death of at least 12 workers, an estimated $5.2 billion in damages and an unknown level of pollution.

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