Plaintiffs challenged the approval in federal district court, claiming that HUD violated NEPA in approving the plan. The district court rejected the claim, but the court of appeals reversed, finding that HUD failed to include an adequate range of alternatives. The court of appeals instructed HUD to prepare a study that explained how “within the framework of the Plan its objective of economic integration can best be achieved with a minimum of adverse environmental impact. HUD prepared a study, entitled “Special Environmental Clearance” in 1977. The study evaluated nine additional alternative locations for the project, and determined that none of the new alternatives were suitable. HUD found that some of the alternatives were not suitable based on the likely two-year delay in implementing the project that would result from selecting the alternatives. The court of appeals again rejected the plan, finding that HUD could not reject an alternative based on delay in implementation. The court of appeals held that delay in implementation could not be “an overriding factor” in rejecting an alternative. The court stated that “environmental factors, such as crowding low-income housing into a concentrated area, should be given determinative weight.” HUD requested Supreme Court review of the decision.