An environmental group filed a lawsuit in an Idaho federal district court against the Bureau of Land Management (BLM), alleging the agency is stonewalling the release of information on the potential impact a proposed 5,000-well drilling project in Wyoming’s Powder River Basin (PRB) would have an endangered species.

In a Freedom of Information Act case, the Western Watersheds Project (WWP) filed a lawsuit in U.S. District Court for the District of Idaho earlier this month seeking to compel BLM to disclose conversations it had with the U.S. Fish and Wildlife Service (FWS) regarding threatened and endangered species.

WWP is concerned that wildlife in Converse County, WY, in the heart of the PRB, could be impacted by drilling plans by units of Anadarko Petroleum Corp., Chesapeake Energy Corp., RKI E&P LLC, Samson Resources II and SM Energy Co. Drilling by the exploration and production companies could require amendments to BLM’s Casper Resource Management Plan.

Last January, BLM issued a draft environmental impact statement for development over a 10-year period. The Converse County project would cover 1.5 million acres, with about 6% (88,466 acres) to be built on BLM lands. Of the 1.5 million acres, 83% are private lands, 7% are state lands and 4% are U.S. Forest Service lands.

“The public has the right to know what federal agencies are saying to each other about rare plants and wildlife,” said WWP spokeswoman Kelly Fuller. “What is the BLM hiding?”

WWP lists six possible threatened or endangered species at risk from the proposed project. Fuller said extensive oil and gas development as outlined in the Converse County project would also harm the greater sage grouse habitat, particularly in the Douglas Core Area, as well as various elk, deer and fish species.

In 2014, BLM began the environmental review process for a major proposed multi-year oil and natural gas drilling project in east-central Wyoming, noting that it could force federal authorities to adjust their current species and habitat protection requirements.