U.S. conservation group Sierra Club has filed suit against the U.S. Army Corps in a San Francisco, California, federal court. It charges that the Corps has wrongly withheld records describing the path of TransCanada Corp's 1,408 km Keystone oil pipeline connecting oil sands in Alberta with refineries along the Gulf Coast of Texas and Louisiana.

Sierra said release of the documents is crucial for a full understanding of the pipeline's potential impacts on communities and water resources threatened by a tar sands oil spill.

Leveraging the U.S. Freedom of Information Act, the club has repeatedly called for documents related to the review of the $5.4 billion pipeline project to be made public. While the Army maintains that the Act does not apply to the documents in question, Sierra believes it does, as the papers were filed by a private company.  

TransCanada applied more than five years ago for a permit to build the 1,409-kilometer pipeline. It is planned to run from the US-Canada border to Steele City, Nebraska, from where it would connect to an existing network.

In its final environmental review of the TransCanada proposal, the U.S State Department on Jan. 31 found the pipeline would not greatly increase carbon emissions because the oil sands in Alberta would be developed anyway. The positive report was said to increase the likelihood that the pipeline will win approval.

Many major U.S. and international conservation and environmental groups have opposed Keystone, saying it would exacerbate global warming.

In other news, the Sierra Club has notified the U.S. Environmental Protection Agency (EPA) that it plans to sue the agency over its failure to enforce sulfur-pollution laws.

The 60-day notice of intent is the first step before filing a lawsuit under the Clean Air Act's citizen action provision, which allows private parties to sue over alleged violations of the Act not being myursued by state and federal regulators.

Although more than 30 states have not submitted the required sulfur pollution plans, Sierra said the EPA has not taken action against any state.