The special counsel hired by the state to look into mining investigations conducted last year by federal and state authorities in eastern Alaska found no evidence that investigators broke laws.
Attorney Brent Cole says in his report that Environmental Protection Agency task force members acted appropriately while carrying out their investigation. He said no miners appeared to have been intimidated during the incident, which saw three to seven task force members check about 30 sites in the Fortymile region near Chicken for Clean Water Act violations.
However, Cole questioned the need for a criminal investigation rather than a civil or administrative inquiry, saying that introduced "an unnecessary element of risk" into the process.
He also found poor levels of communication between federal and state agencies.
Gov. Sean Parnell released the report Thursday. He says he remains disturbed by the operation.
In a statement, the EPA says the report confirms investigations were conducted "professionally and courteously."
Channel 2's Chris Klint contributed information to this story.