The State of New Jersey (D) banned the importation of refuse into the state for disposal. The intent of the law was to help the environment. The law was motivated by the interplay of decreasing availability of disposal waste sites in New Jersey, the increase of disposable waste, and the degree of risk associated with disposing waste collected outside of New Jersey. The New Jersey legislature believed that continued use of New Jersey disposal sites for outside disposal would incapacitate New Jersey facilities within a short period of time. To manufacture new disposal sites would induce substantial environmental burden to New Jersey wetlands and exacerbate pollution conditions. Philadelphia (P) and other entities interested in disposing in New Jersey challenged the law. The New Jersey Supreme Court upheld the measure; the statute did not violate the Commerce Clause because it addressed environmental, rather than commercial interests. The plaintiffs then appealed to the Supreme Court. It remanded for reconsideration of the appellants' preemption claim in light of the newly enacted Resource Conservation and Recovery Act. Again, the New Jersey Supreme Court found no federal preemption of the state law, and again the Supreme Court noted probable jurisdiction.