Those aren't tar sands though. That's shale/fracking (I think) from the Bakken.
Sounds like ND is still producing.By October 2020, total oil rig count in North Dakota had fallen. According to the North Dakota Department of Mineral Resources, the total oil rig count in the state had fallen from 58 active rigs on October 3, 2019, to only 11 active rigs on October 3, 2020, a reduction of over 80 percent.[27] However, oil production hit an all time high of 1.5 million barrels per day in 2019. Demand fell temporarily due to Covid-19. Oil prices have since recovered to over $70 per barrel in 2021 due to increased demand linked to the Covid-19 recovery. North Dakota remains the state with the second highest oil production, after Texas.[28]
Wells (extraction) take a lot less manpower than rigs (drilling), so it makes less noise. The rig boom ended 8 years ago.