Federal agency accident records show that the ExxonMobil pipeline that spilled thousands of gallons of oil near Little Rock in March has had at least 13 minor leaks since 2002.

The federal Pipeline and Hazardous Materials Safety Administration documents, obtained by the Arkansas Democrat-Gazette (http://bit.ly/12xqBln) through a Freedom of Information Act request, indicate that corrosion caused six of those leaks.

"Corrosion is very common for pipelines," said James Williams, an energy analyst who operates WTRG Economics near Russellville, "(Companies) try to catch the stuff ahead of time; sometimes they don't."

The March rupture of the 65-year-old pipeline leaked more than 100,000 gallons of oil into the Mayflower neighborhood about 25 miles northwest of Little Rock. About 20 homes were evacuated.

ExxonMobil spokesman Aaron Stryk said the 13 leaks did not take place on the main Pegasus pipeline.

"They were within our facilities and generally involved small releases from pumps, valves, fittings or from ancillary piping," he said in an email to the newspaper. "Three of the events . involved a pipeline other than Pegasus."

A letter from the Pipeline and Hazardous Materials Safety Administration accompanying the FOI request response said the 14 reports — including the Mayflower spill — "have been filed by both Mobil and ExxonMobil for the Pegasus System."

About 25 percent of pipeline accidents are caused by corrosion, according to the pipeline agency. Thirty-six percent of pipeline incidents are caused by welding or equipment failure.

The largest of the 13 spills was 15 barrels in Illinois in 2008, while the others ranged from 10 gallons to four barrels. One barrel contains 31.5 gallons.

Reports from the pipeline agency also show that ExxonMobil was fined $26,200 in 2010 for not inspecting a section of the pipeline beneath the Mississippi River between Missouri and Illinois within the five-year time frame required by federal regulations.

The 20-inch-wide Pegasus pipeline stretches 850 miles from Patoka, Illinois, through Arkansas to Nederland, Texas. It passes through the Lake Maumelle watershed, the drinking-water source for about 400,000 people in central Arkansas, on its 300-mile run across the state.