The Dakota Access pipeline already had its first leak – 84 gallons of oil – at a pump station in South Dakota in early April, sparking outrage and calling into question its environmental safety.

[...] The report of the spill can be found on the Department of Environmental and Natural Resources website. The agency apparently did not make any official announcement on the incident as it was relatively minor and had no environmental impact, according to Brian Walsh, a scientist with the department, as cited by the Guardian. The site "was cleaned up right away," the official added as quoted by ABC news.

The spill occurred less than 110 miles from Lake Oahe, which supplies Sioux tribes with water.