Oil is flowing from a drill site in what is now the farthest-west producing site on Alaska’s North Slope, ConocoPhillips Alaska Inc. said on Oct. 9.

Production at Greater Mooses Tooth 1, a prospect on the western edge of existing Arctic Alaska oil development, started Oct. 5, ConocoPhillips (NYSE: COP) said.

Production at GMT 1 is expected to peak at 25,000 barrels a day (bbl/d) to 30,000 bbl/d, the company said. It is the second producing oil field within the borders of the National Petroleum Reserve in Alaska, or NPR-A, a vast federal land unit on the western side of the North Slope.

“This is another milestone for development in the NPR-A,” Joe Marushack, president of ConocoPhillips Alaska, said in a statement.

Oil from GMT 1 is being sent by pipeline east for processing at the ConocoPhillips-operated Alpine field. That oil is then shipped by pipeline to Prudhoe Bay about 50 miles (80 km) to the east, then south through the Trans Alaska Pipeline System.

The first field to begin producing within the reserve boundaries was a ConocoPhillips field called CD5, where startup occurred in 2015.

ConocoPhillips is seeking to develop a related drill site about 8 miles (13 km) to the southwest of GMT1 that could start production by 2021. Peak production at that site, Greater Mooses Tooth 2, would be 35,000 bbl/d to 40,000 bbl/d, according to ConocoPhillips.