Mineral Policy Center v. Norton 292 F. Supp.2d 30 (D.D.C. 2003) The Bureau of Land Management (BLM) revised their regulations governing hardrock mining activities on public lands (43 C.F.R. §3809). BLM originally had a regulations designed to prevent "unnecessary or undue degradation." They had recently revised their regulations to the "substantial irreparable harm" (SIH) standard. Under SIH, BLM would deny a mining permit if the miner's plan could result in substantial irreparable harm that could not be effectively mitigated. The Bush administration came into power, and BLM did an abrupt about-face and was revising §3809 to basically say that since "unnecessary" sounded synonymous with "undue" only unnecessary degradation would be prevented (and therefore degradation that was undue but necessary would now be ok.) Despite the fact that the regulations says "unnecessary or undue", not "unnecessary and undue." Environmental Groups, led by the MPC sued for an injunction, claiming that the revisions would substantially weaken or eliminate BLM's authority to protect lands from mining activities. The MPC argued that BLM's governing Statute, the Federal Land Policy and Management Act of 1976 (FLPMA) required the BLM to "take any action necessary to prevent unnecessary or undue degradation of the public lands." BLM argued that the SIH standard was overboard and outside of what FLPMA authorized. BLM was just going back to the historical standard. The Trial Court found for BLM. The Trial Court found that FLPMA was clear and that BLM is to have regulations that prevent unnecessary degradation but also degradation that, while necessary to mining, is undue or excessive. However, the Court found that the terms "unnecessary" and "undue" are not defined in FLPMA. As such, the Court is to defer to Agency discretion on how to interpret ambiguous terms within FLPMA. See Chevron U.S.A. Inc. v. Natural Resources Defense Council (467 U.S. 837 (1984)).