WASHINGTON — Interior Secretary Dirk Kempthorne pledged yesterday to squelch the “ethics storm” exposed by investigators who said agency workers rigged bids, accepted gifts, and had sex with energy company officials doing business with the government.

Mr. Kempthorne is considering firing eight employees still at the Minerals Management Service, putting in place a random drug-testing program and banning all employees in that division from receiving gifts and gratuities. A new attorney-adviser will focus on ethics.

“I can assure the committee that this process will be completed as swiftly as possible and we will examine the full spectrum of disciplinary actions, including termination,” Mr. Kempthorne told the House Natural Resources Committee. The employees, all civil servants, are entitled to at least 30 days notice before being fired and are granted time to respond.

In reports last week, the department’s internal watchdog chronicled a fraternity house atmosphere inside a division office in Denver between 2002 and 2006. That office, which has around 50 employees, is responsible for marketing billions of dollars worth of oil and natural gas that energy companies barter to the government in lieu of cash royalty payments for drilling offshore.

Nine of the employees allegedly received thousands of dollars in gifts, including meals, ski and golf trips, concert tickets, and snowboarding lessons. Two workers accepted gifts on 135 occasions from four companies that did business with the Denver office — Shell, Chevron Corp., Hess Corp., and Denver-based Gary-Williams Energy Corp.

Several employees dated oil company traders, and used cocaine and marijuana, according to the reports by Inspector General Earl E. Devaney that also claimed cocaine was delivered to the office in one instance.

Devaney said the employees’ conduct was “egregious” and that he could not explain the behavior of oil and gas company representatives. He questioned why the Justice Department decided not to go after two employees who have left the office but who allegedly rigged contracts.

Two other former employees, based in Washington, have pleaded guilty — one for violating conflict of interest law, the other for violating post-government employment restrictions.

“Simply stated, the MMS employees named in these latest reports had a callous disregard for the rules by which the rest of us are required to play,” Mr. Devaney said. But, he said, it is also “disingenuous for employees of such major organizations … to pretend that they thought it was permissible to provide federal government employees with gifts in excess of well-known limits.”

Mr. Devaney said there was no evidence that any of the personal relationships brought benefits to the oil companies, but he said there should be a ban on accepting gifts and gratuities from any industry. Last year, the government received $4.3 billion in royalty-in-kind payments.

Federal employees currently are barred from accepting individual gifts over $20 and can accept no more than $50 in gifts each year.

Some companies named in the reports said they were taking action themselves.