\n\t\t<\/aside>\nOn March 3, 1991, Lakehead Pipeline Company’s Line 3 ruptured near Grand Rapids, Minnesota. An estimated 1.7 million gallons of oil spilled into the nearby Prairie River and surrounding wetlands, making it the largest inland oil spill in U.S. history. <\/p>\n
Line 3 was built in the 1960s by the Lakehead Pipeline Company to transport oil from Canada to the Midwest. It passed near the Prairie River, east of Grand Rapids, Minnesota. On March 3, 1991, a 34-inch-long pipeline ruptured along a small crack, creating a 5-foot-long crack in the pipe. The pressurized oil shot up into the air, quickly covering surrounding trees and spilling into the Prairie River and nearby wetlands.<\/p>\n
At 12:40 p.m., local residents reported a strong odor of oil to the fire department, who immediately alerted Lakehead. The company shut down power lines at 1:30 p.m. The 200 to 300 residents who lived near the oil spill site were evacuated for the rest of the day, and Highway 169 east of Grand Rapids was closed for several hours due to its proximity to the spill site.<\/p>\n\n\t\t<\/aside>\n\n\t\t<\/aside>\nRelated: December 1962: Oil spill into Mississippi River causes ecological disaster<\/em><\/strong><\/h3>\nLakehead initially estimated that the pipe burst spilled about 630,000 gallons of oil, but that estimate was later nearly tripled to 1.7 million gallons. Wetlands and vegetated riverbanks were the main environments affected by the spill, and samples of river water, groundwater, and well water were taken to assess the extent of damage. Although a few fish died where the oil first entered the stream, there was little impact on other wildlife.<\/p>\n\n\t\t<\/aside>\nBecause the Prairie River is a tributary of the Mississippi River, the impact could have been widespread, but several factors kept the damage limited. Colder temperatures make the oil more viscous, so it moves more slowly than in warmer weather. In addition, the Prairie River was covered with 18 inches of ice, blocking much of the oil from entering the waterstream. The frozen ground limited the amount of oil absorbed into the soil, and the absence of migratory birds prevented widespread impacts to wildlife.<\/p>\n
Cleanup efforts took months and cost millions of dollars. Steve Uri oversaw about 90 people from several Midwestern states to manage the Lakehead site cleanup. Crews worked 12-hour shifts around the clock, unless temperatures were too cold to safely operate machinery, and employed several methods to stop and recover the spilled oil.<\/p>\n
Downstream from the spill, crews cut large grooves in the ice with chainsaws and set up submerged booms to prevent oil from spreading into the Mississippi River. Large tiers of absorbent material are built on top of the ice to absorb any oil that is still sliding downstream on the surface. Officials used a squeegee to force the oil onto the ice and transported it to a designated collection point, where a vacuum was used to remove the oil. The oil-soaked ice was cut into movable blocks and transported to unaffected parts of the river. Crews sprayed the block with hot water to release oil, which was recovered with a skimmer. The only slightly contaminated ice was removed from the river and thawed in lined reservoirs. Once the ice melted, oil was recovered from the pond. Governor Arne Carlson visited the oil spill site during the cleanup and praised Lakehead’s efforts and cooperation with state officials.<\/p>\n\n\t\t<\/aside>\nAfter the initial cleanup was completed, Lakehead constructed a pond near the oil spill site to collect the spill as the ground thaws and releases more oil. By June, Lakehead had spent $7 million on cleanup efforts and petitioned for permission to release water from the reservoir into the Prairie River.<\/p>\n