An independent court assessment has proposed that Chevron pay a minimum of $7 billion and up to $16 billion to compensate for environmental contamination caused to Ecuador's Amazon rainforest during a 26-year period when the oil giant operated a large concession in the country.

If the assessment is accepted by the court, the subsequent judgment will most likely be the largest civil damages award in an environmental case.

The higher $16 billion figure could result if the court accepts an unjust enrichment penalty tied to Chevron’s actual cost savings over several decades for failing to use appropriate operational practices.

The lower figure represents actual costs to remediate soils around all 378 of Chevron’s former Ecuador production facilities, plus compensation for health care costs, development of a water system, loss of indigenous land, ecosystem impacts, infrastructure improvements and other categories of damages.

The report, one of the last steps in the class action trial that began in New York in 1993, will help answer one of the most disputed questions in the case. For years, plaintiffs have reportedly estimated environmental damages to be roughly $6 billion, later adjusted to $10 billion, while Chevron claimed they were negligible.