JUNEAU — A watchdog plans to review the U.S. Environmental Protection Agency’s handling of a report on the potential effects of large-scale mining on a world-premier salmon fishery in Alaska’s Bristol Bay region.

Congressional requests and hotline complaints prompted the audit, Ashley Sellers-Hansen, a spokeswoman for the EPA inspector general’s office, said Tuesday. It will look at whether the EPA followed laws, regulations and policies in developing its report, according to a memo from the office.

The state of Alaska and the owner of the proposed Pebble Mine, Northern Dynasty Minerals Ltd., were among those who requested the inspector general investigate the EPA’s preparation of the Bristol Bay watershed assessment. Both have raised concerns about potential bias within the federal agency, citing emails obtained through records requests, and the threat of a pre-emptive veto of the project before it enters the permitting phase.

U.S. Sen. Lisa Murkowski and Rep. Don Young, both Alaska Republicans, urged the office to investigate after complaints were raised.

The EPA said in a statement that it will work with the inspector general’s office to provide information, but defended the report, saying it considered public comment and scientific data.

The “EPA made transparency and public engagement a priority from day one of the Bristol Bay Watershed assessment,” the statement said. “It is a strong scientific document based on hundreds of peer reviewed studies.”

The agency added that it responded to numerous public-records requests and congressional calls for information.

Earlier this year, the EPA initiated a process under which it could restrict or prohibit development of the mine after concluding that large-scale mining in the Bristol Bay watershed posed significant risks to salmon.

An early phase of that process called for the state, those behind the proposed mine and the U.S. Army Corps of Engineers to submit information showing mining-related discharges wouldn’t produce “unacceptable adverse effects” to aquatic resources or that actions could be taken to prevent such effects.

Both the state and the Pebble Limited Partnership, in their latest responses dated last week, continued to push back against the process as premature. The Pebble Partnership is working to advance the mine project.

An analysis of the potential mine effects should happen amid the permitting process, Pebble Partnership CEO Tom Collier wrote to regional EPA Administrator Dennis McLerran. To analyze the impacts in the absence of a development plan and on an accelerated schedule is “tantamount to denying due process by foreclosing opportunity for science to be objectively presented, reviewed and assessed.”