* Almost two months since Mayflower, Arkansas, spill
* Arkansas politicians demand part of line rerouted
By David Sheppard
NEW YORK May 24 (Reuters) - Exxon Mobil Corp is still waiting for test results from the ruptured section of its 95,000 barrel-per-day (bpd) Pegasus pipeline, almost two months after it spewed 5,000 barrels of oil into an Arkansas suburb, the company said on Friday.
The Pegasus spill intensified the debate about the safety of transporting oil from Canada's tar sands across the United States. After a second far-smaller spill was discovered on the nearly 70-year-old line in Missouri last month, speculation has mounted the line could be down for much longer than initially anticipated.
The Pegasus line, which carries heavy Canadian crude from Patoka, Illinois, to Nederland, Texas, has been shut since it first burst in late March, leading to the evacuations of homes in Mayflower, Arkansas, and sparking a huge cleanup effort.
"It is premature to speculate on future plans for the pipeline until the investigation into the cause of the incident is completed," said Exxon Mobil spokesman Aaron Stryk in an email.
"We are still waiting on the results from the metallurgic lab testing. The information we gain from the investigation into the cause will inform the development of our plans in the future."
Exxon cut out a 52-feet (15.8 meters) section of the damaged pipeline in mid-April and sent it to an independent third-party laboratory to try to determine the cause of the spill.
Arkansas Attorney General Dustin McDaniel, who launched an investigation into the oil spill, said in April the rupture was more than 22 feet (6.7 meters) long and two inches (5 cm) wide.
The shutdown of the line has seen large volumes of crude oil on the Keystone pipeline from Canada diverted into Cushing, Oklahoma, delivery point of the U.S. crude oil contract.
Keystone normally splits at Steele City, Nebraska, before flowing to either Cushing or Patoka, but the shutdown of Pegasus has seen oil back up around the Illinois terminal.
Politicians in Arkansas have asked Exxon to relocate a 13.5 mile section of the line that runs through the Lake Maumelle watershed, the main source of drinking water for the state's largest city, Little Rock.
"The only way to eliminate all risks posed by the pipeline to Lake Maumelle is to relocate the Pegasus pipeline out of its watershed," said U.S. Senators Mark Pryor, John Boozman, and other Arkansas politicians in the letter dated May 15 and published on the arkansasmatters.com website.
"The Lake Maumelle Government Stakeholders expect immediate action on our request to relocate this pipeline out of the watershed and to see this project completed within 3-5 years."
The letter also requests a series of shorter-term steps the Government Stakeholders group wants Exxon to take before restarting the line, including adding remote isolation valves to the section that runs through the watershed.
The U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration (PHMSA) requires Exxon to submit a detailed start-up plan to the regulator for approval before it can use the line again.
Two weeks ago, PHMSA threw out an appeal by Exxon to let them restart a section of the line below the site of the spill, with the regulator ruling its 'Corrective Action Order' should remain in place on the entire 850 mile length of the line.
Other companies are also waiting to see when the line will restart.
Sunoco Logistics Partners LP said earlier this month that the start-up of a 40,000 bpd section of its West Texas-to-Nederland Texas on the Gulf Coast pipeline has been delayed until Pegasus has been repaired, as it connects into the Exxon line.
A spokesperson for Sunoco declined to comment on Friday.