Kern County's top oil regulator retired abruptly Friday, becoming the second person in two years to leave the post earlier than planned.

Burt Ellison, 55, declined Wednesday to specify his reasons for stepping down, but blamed state bureaucracy.

As district deputy in Bakersfield for the state Division of Oil, Gas and Geothermal Resources, Ellison managed about 50 engineers, technicians and other staffers stationed at the agency's largest and busiest field office.

Ellison said he plans to follow in the steps of his father and grandfather, both geologists who explored for oil and produced it as independents.

"I'll be hanging out a shingle" as a registered petroleum geologist, he said.

Ellison joined DOGGR in 1989 and transferred to its Bakersfield office in 1992.

He became district deputy June 1, 2012, after his predecessor, Randy Adams, was put on paid suspension in April 2011 and ordered back to work three months later. The reason for Adams' suspension was never disclosed publicly. He left the job permanently in summer 2011 but didn't retire officially until October of that year.

Ellison remains an employee of the state as he uses up accumulated vacation time.

A spokesman for DOGGR and its parent agency, the state Department of Conservation, declined to discuss Ellison's departure, citing confidential personnel matters.

The agency's Bakersfield office has seen rapid growth in recent years as it works to meet industry demand for drilling, waste disposal and other kinds of oilfield permits. Preliminary state data show that the district consisting almost entirely of Kern County produced about 72 percent of California's oil last year and 85 percent of its natural gas.

There was no word Wednesday on who will manage the Bakersfield office going forward or how soon DOGGR hopes to have a new district deputy in place.

For his part, Ellison said he decided to leave because "state employment has a lot of rules regarding personnel and administration and managing the affairs of the state."

He added that the division provided him with a "great career."

"I have no ill feelings," he said. "I'm just ready to move on."