RENO, Nev. (AP) — U.S. regulatory fines issued to Nevada utilities for failing to ensure a reliable delivery of energy since 2009 range from a $52,000 settlement with Nevada Power Co. for mostly reporting deficiencies to a $2,000 penalty in Lincoln County for having insufficient procedures to notify the FBI about threats of sabotage, a review of the records shows.

None of those violations cited in public records posed any serious or substantial risk to the region's bulk power system, the North American Electric Reliability Corp., known as NERC, concluded in its reports to the Federal Energy Regulatory Commission during that period.

The case involving Lincoln County Power District No. 1 had the potential to have a moderate impact on the system if a threat of sabotage ever materialized, NERC said, adding there was no evidence that ever happened.

The utility "relies on the county sheriff to contact the FBI and has no established communication directly with the FBI," the Western Electricity Coordinating Council said in a 2009 summary of the violation. "Without proper contact with the FBI it would be difficult to be certain that appropriate personnel are aware of sabotage events."

The utility serving about 1,000 customers in southern Nevada had revised its plans and already trained employees on new procedures within 10 days of an audit in May 2008, NERC said.

Similarly, the concerns about Nevada Power's reporting deficiencies stemming from an audit in May 2008 were addressed in mitigation plans completed before the formal penalty was authorized on March 1, 2010.

Nevada Power, a former subsidiary of NV Energy that is now owned by Warren Buffet's Berkshire Hathaway, acknowledged it had analyzed its system only with respect to heavy demands during the hot summer months because of spikes in the use of air conditioning rather than "over the range of forecast system demands," as required.

NERC concluded no larger penalties were warranted because the alleged violations were Nevada Power's first for the applicable reliability standards; the utility was cooperative throughout the process; there was no evidence of any intent or attempt to conceal a violation; and the alleged violations did not pose a serious or substantial risk to the bulk power system.

NV Energy spokeswoman Faye Anderson said there have been no similar problems since and declined further comment.

"Really this was so long ago, we have nothing new to add," she said in an email last week to The Associated Press.

NERC sometimes doesn't disclose the identity of violators in the settlement agreements so it's not possible to determine if additional Nevada utilities were investigated for alleged violations during the period.

Other significant settlements involving Nevada utilities documented in public records since 2009 include:

— Newmont Nevada Energy Investment LLC, $16,000 in 2013 for insufficient testing of communication systems, voltage and sensing devices.

— Las Vegas Cogeneration, $12,000 in 2010 for a testing program lacking required maintenance and testing procedures, including verification of voltage, control circuitry and breaker-failure relays.

— Overton Power District, $10,000, in 2010 for failure to have a maintenance and testing program for its protection system, and failure to produce documented and published facility-connection requirements.