Donnelly, 494 U.S. 820, 110 S.Ct. 1566, 108 L.Ed.2d 834 (1990), are important in resolving the question of whether federal jurisdiction is exclusive in citizen suits brought under the RCRA. These two cases require that Congress either expressly states that federal jurisdiction is exclusive or in some other affirmative way overcomes the strong presumption that jurisdiction is concurrent with state courts. This doctrine is an integral part of our system of federalism. The federal courts cannot create Congressional intent, if it is left unstated, by making an assumption that federal jurisdiction should be exclusive. Rather, the strong presumption is in favor of concurrent jurisdiction in the state courts. See Holmes Fin. Assocs. v. Resolution Trust Corp., 33 F.3d 561, 565 (6th Cir.1994) (<HOLDING>). In the instant case, we find that the citizen
holding that federal courts must apply state substantive law in diversity cases holding that state courts must apply the federal pleading standard in fela cases holding that plaintiffs complaint did not invoke federal courts arising under jurisdiction because it put forth alternate state and federal policies to support its state law claim holding that in diversity cases federal courts are to apply state substantive law and federal procedural law holding that congress must affirmatively divest the state courts of their presumptive competence to heai cases arising under federal law