A district court preliminarily enjoined EPA's and the U.S. Army Corps of Engineers' controversial "waters of the United States" rule. Thirteen states—Alaska, Arizona, Arkansas, Colorado, Idaho, Missouri, Montana, Nebraska, Nevada, New Mexico, North Dakota, South Dakota and Wyoming—challenged the...

A California court held that revised "curtailment letters" that the state water board sent to irrigation districts and water appropriators in the Central Valley no longer violate due process, and therefore denied the districts' motions for a preliminary injunction. The court previously ruled that th...

A district court held that a mining company violated state and federal permits when it discharged high levels of ionic pollution. Environmental groups successfully demonstrated that high conductivity discharges from two of the company's mines are causing or materially contributing to the biological ...

The Seventh Circuit upheld EPA's approval of revisions to Illinois' SIP, thereby rejecting challenges raised by Indiana. Indiana argued that the relaxation of Illinois' vehicle emissions testing program will decrease the likelihood that the Chicago area—which includes two Indiana counties—will a...

A California court denied an environmental group's motion to preliminarily enjoin emergency regulations governing the underground injection of wastewater produced by oil drilling. The emergency regulations establish a timeline for companies to stop injecting into certain wells, but it still gives so...

The D.C. Circuit denied an environmental group's petition for review challenging FERC's decision to issue a natural gas pipeline operator a certificate of public convenience and necessity to extend a natural gas pipeline in Maryland. The group argued that FERC's issuance of the conditional certifica...

A district court held that it lacks jurisdiction over Oklahoma's lawsuit against EPA challenging its proposed emission standards for coal-fired power plants. The state argues that the proposed emission standards, if adopted as a final rule, would constitute an ultra vires action in violation of the ...

The D.C. Circuit, on remand from the U.S. Supreme Court, invalidated EPA's 2014 emissions budgets under the transport rule, also known as the Cross-State Air Pollution Rule, as applied to various states. The CAA's "good neighbor" provision requires upwind states to prevent sources within their borde...

The D.C. Circuit denied petitions challenging an EPA regulation that revised the NESHAP for hexavalent chromium, a carcinogenic compound that gets emitted into the air during the chrome-finishing process. The new rule, issued in 2012, imposes more stringent emissions limitations than its predecessor...