We submitted joint comments on the Army Corps of Engineers’ environmental assessment of the Pebble Mine Project in southwest Alaska. The Corps quantifies greenhouse gas emissions from the project but fails to provide a monetized estimate of the climate damages those emissions will produce.
Extraction of copper, gold, and molybdenum at Pebble Mine will be powered by a newly-constructed 270-megawatt electricity generating plant and a 188-mile natural gas pipeline. The draft environmental impact statement for the project estimates that operation of the mine will emit almost one million tons of greenhouse gas each year. The Corps does not monetize the damages that will result from the project’s emissions, despite monetizing other effects, like taxes and royalties. Our comments ask the Corps to use social cost of greenhouse gases metrics, which are the best available tool for weighing the significance of climate impacts.