Colorado approved about 5,100 oil and gas drilling permits last year, down from the record 8,027 issued in 2008 before the recession.
But after a drop-off earlier in the year, the number of applications steadily increased toward year's end, said Dave Neslin, head of the Colorado Oil and Gas Conservation Commission. The roughly 640 permits approved in December were more than in December 2007, when a total of 6,368 permits were issued, Neslin said Tuesday.
"Compared to the other states, we're still one of the most active in the country," Neslin said.
Energy companies and industry groups have blamed new oil and gas regulations for longer processing times for permits. They say that has discouraged development.
Regulators insist they have made progress on reducing a backlog of applications and cutting the processing time from more than 80 days to an average of 45 days toward the end of last year.
The backlog grew as companies submitted applications to beat the new rules, which took effect April 1.
Williams Production spokeswoman Susan Alvillar said the company is working with the oil and gas commission as the agency's staffers get used to the revamped permitting process. She said one of the company's applications took 101 days and another with fewer wells took 80 days.
"I still think it's really an ongoing process," Alvillar said.
The industry appreciates the state's effort in cutting the time it takes to issue permits, said Tisha Schuller, the new president of the Colorado Oil and Gas Association, a trade group. "We have seen an improvement overall," she said.
The industry group wants to make sure the commission has "stable and adequate staff" to handle the workload, Schuller added.
The agency has hired more employees after getting authorization from the Legislature.