Plaintiffs appealed from a judgment of the district court vacating summary judgment for defendants where plaintiffs alleged that defendants, operator of a calcium carbonate mineral processing facility, were liable for creating an "imminent and substantial endangerment" within the meaning of the Resource Conservation and Recovery Act of 1976 (RCRA), 42 U.S.C. 6901-92. Liability was predicated upon a finding that aminoethylethanolamine (AEEA) was present in defendants' waste. The court held that plaintiffs' claim that AEEA presented an imminent and substantial endangerment in violation of the RCRA was properly dismissed under Federal Rule of Civil Procedure 12(b)96) where plaintiffs' failure to specify arsenic in their notice of intent to sue (NOI) supported the district court's dismissal of the endangerment claim and the open dumping claim. The court held that the dismissal of the action would not prohibit plaintiffs from again giving notice to defendants and filing its suit in compliance with RCRA's notice and delay requirements upon future discovery of potential violations of the federal environmental laws. Accordingly, the judgment was affirmed.