Carlos Rodriguez-Perez, Carmen Ortiz-Lopez, Carlos M. Belgodere-Pamies, and Janet Roe owned and operated a gas station. Operated as a retail service station from the mid-1930s until August 1998 when it was closed, the station sold gasoline, diesel fuel, automobile parts, and motor oil. There was significant disposal of hazardous substances on the premises during the station’s operation under Rodriguez’s management. Motor oil drained from automobiles was allowed to flow into the Pinones River, a body of water located behind the station. Similarly, large quantities of used oil filters were found buried in the northern part of the station. Gasoline and diesel used to flush dirt and grease from vehicles were rinsed onto the ground and into the river using a pressure hose. As a result, the premises became contaminated with a number of hazardous substances, including lead, chromium, benzene, ethylbenzene, toluene, and xylene. Esso Standard Oil Company, the owner of the gas station after Rodriguez-Perez and the others, had to pay to have the station cleaned up. Esso brought suit under CERCLA against Rodriguez-Perez and the other owners. Esso primarily sought relief contribution under CERCLA § 113(f) for the response costs that Esso incurred in remedying environmental contamination at the gasoline station. The magistrate judge dismissed the CERCLA claim. Did the magistrate judge err in judgment? Esso Standard Oil Co. v. Rodriguez-Perez, 455 F.3d 1 (1st Cir. 2006).