unable to do so, further delaying the shutdown of the line. The NTSB investigation synopsis pointed to corrosion fatigue as the underlying cause of the catastrophic breach. The incident was exacerbated by the pipeline's disbonded polyethylene tape coating. In July 2012, the cost of the cleanup operations was estimated at $767 million. The NTSB stated the Enbridge dilbit oil spill is, as of 2012, the costliest onshore cleanup in U.S. history. NTSB Chair Deborah Hersman likened "Enbridge's poor handling" of the spill to the Keystone Kops, asking: "Why didn't they recognize what was happening, and what took so long?" NPR reported that "NTSB investigators determined that the gash in the pipe was caused by a flaw in the outside lining which allowed the pipe to crack and corrode. Now, in 2005, Enbridge actually had learned that this section of pipe was cracked and corroding. ... That same 2005 internal report pointed to 15,000 defects in the 40-year-old pipeline. And Enbridge decided not to dig up this [Talmadge Creek] area to inspect it." In 2013, in opining on the Keystone XL pipeline proposal, the EPA recommended to the State Department that pipelines that carry bitumen should no longer be treated just like pipelines that carry any other oil. Stephen Hamilton, an ecology professor at Michigan State University and the independent science adviser at Talmadge Creek, detailed the challenges and expense of the still-ongoing Michigan cleanup. Additional dredging under 2013 order The EPA issued an Order for Removal in 2013 which required Enbridge to remove oil-contaminated sediment from specific locations along the Kalamazoo River, including the three areas where submerged oil was most pronounced: Upstream of the Ceresco Dam (along Riverside Farm) Mill Ponds area Morrow Lake, Morrow Lake Delta and adjacent areas Sediment traps at two designated locations By the fall of 2014, Enbridge had completed the remaining obligations under the 2013 Order for Removal, including the dredging of oil-contaminated sediment. Based on the successful completion of the work by Enbridge, the EPA transitioned the oversight of the remaining obligations to the Michigan Department of Environmental Quality in 2014. Safer oil and gas transportation; renewable energy One of the results of the Enbridge spill into the Kalamazoo River is that two fossil fuel companies with operations in the Kalamazoo, Michigan area have additional technology in use to assist oil and gas that is transported. These same two companies, Wolverine Oil and