Federal oilfield inspectors are working to clear a backlog of hundreds of uninspected well sites on public and tribal lands in the Dakotas.
The Bureau of Land Management says agency regulators are being brought in from other states to help catch up with inspections on "high priority" sites. Those sites have a high pollution risk or are located near environmentally sensitive areas.
BLM spokesman Loren Wickstrom says keeping pace with the North Dakota's booming oil production has been a challenge.
But he says about half the 335 sites identified as high risk in North Dakota have been inspected and the rest should be done by the end of the year. He says about 10 sites remain in South Dakota and should be inspected by year's end.