( CNN ) -- Exxon Mobil will pay all of the costs related to last week 's oil spill in an Arkansas neighborhood , a company spokesman said Wednesday . Between 3,500 and 5,000 barrels of heavy crude leaked from a ruptured pipeline -- not 12,000 barrels , as previously reported , according to Exxon Mobil spokesman Alan Jeffers . The company has no timeline yet for when the cleanup around the two dozen homes in a Mayflower , Arkansas , subdivision would be completed , Jeffers said . Excavation of the contaminated soil is under way , weather permitting , he said . He did not have an estimate of the costs of the effort . Arkansas Attorney General Dustin McDaniel has opened an investigation into what caused a 2- or 3-inch gash in the underground Pegasus pipeline , which began spewing crude Friday . McDaniel said Tuesday he asked Exxon Mobil , the owner of the 60-year-old pipeline , to preserve all documents and information related to the spill and cleanup efforts . `` This incident has damaged private property and Arkansas 's natural resources . Homeowners have been forced from their homes as a result of this spill , '' McDaniel said in a statement Tuesday . `` Requesting that Exxon secure these documents and data is the first step in determining what happened and preserving evidence for any future litigation . '' The Pegasus pipeline carries Canadian crude from Illinois to Texas , a state transportation engineer said . Exxon Mobil met with displaced residents over the weekend to explain how they can make claims for losses . `` If you have been harmed by this spill then we 're going to look at how to make that right , '' Exxon Mobil Pipeline Co. President Gary Pruessing told them .
Between 3,500 and 5,000 barrels of heavy crude leaked from a ruptured pipeline . No timeline yet for the cleanup around two dozen Arkansas homes . Excavation of contaminated soil is under way , weather permitting .