Dakota Access pipeline asks U.S. Supreme Court to scrap environmental study order

NEW YORK, Sept 20 (Reuters) - Dakota Access on Monday asked the U.S. Supreme Court to revisit whether the largest pipeline out of the North Dakota oil basin requires additional environmental review.

The U.S. District Court for the District of Columbia scrapped a key environmental permit for the pipeline last year and ordered an additional environmental study. Native American tribes and environmental groups have argued the pipeline threatens to contaminate the Missouri River and vital drinking water sources.

Energy Transfer, which operates the 570,000 barrel-per-day (bpd) pipeline out of the Bakken shale basin, has said its pipeline is safe.

The company said in its petition additional review is unnecessary and that it would impose burdens for other large infrastructure projects.

"This case carries enormous ramifications for the oil industry, its workers, and the nation," the pipeline operators said in the petition.

The company did not immediately comment on Monday. Lawyers for the tribes did not immediately comment. (Reporting by Devika Krishna Kumar in New York Editing by Chris Reese)