YREKA, Calif. - Though U.S. Interior Secretary Ken Salazar won't be making a formal determination on the Klamath dam removal project, the government will still tip its hand later this spring.

Work is continuing on a final environmental document that will choose a "preferred alternative" among six options, which range from doing nothing to fully dismantling the four dams in Southern Oregon and Northern California.

In addition, an overview report on the scientific studies unveiled last fall are undergoing a peer review. The final environmental analysis and scientific report will be out this spring, Salazar's office indicated last week.

After public and written comments were taken on the environmental documents last fall, "now what we do is look at all the comments and provide responses to the comments," said Matthew Baun, a spokesman for the U.S. Fish and Wildlife Service here.

Salazar will choose from among five alternatives in the environmental impact statement, which include full removal of all the dams; partial removal while leaving some structures behind; removing only two of the four dams; and installing fish passages around the dams, Baun said.

The document will provide a clue of Salazar's intentions even though he said he would not be able to make a formal determination by a March 31 deadline. He cited several reasons, including that Congress has not yet passed an authorization bill.

Meanwhile, critics of the dam removal proposal are focusing on a complaint letter sent by former U.S. Bureau of Reclamation science adviser Paul Houser, who claims he was fired after raising concerns about how his superiors were characterizing the draft environmental documents and scientific studies to the public.

In a Feb. 24 letter to the Interior Department's executive secretariat and regulatory affairs office, Houser alleged officials wrote a summary and news release to elicit support for dam removal while downplaying negative remarks from scientists that were in the full reports.

"My disclosure was clearly made to people who had authority to fix the press release ... and people who had influence on the Secretarial decision process," Houser wrote. "My disclosure was never directly addressed, and supervisors have used my probationary status to enact reprisal for the disclosure culminating in the termination of my employment ..."

Houser, who is a professor at George Mason University in Virginia, did not return a call to his office seeking comment.

Government officials noted that Houser's complaints had to do with how the environmental analysis and scientific studies were presented to the public, not the documents themselves. Interior spokeswoman Kate Kelly said Houser's allegations are being reviewed as called for under the department's scientific integrity policy.

"Interior has established a strong scientific, public input and peer review process that is guiding the studies that will lead to a decision" on the dams, she told the Capital Press in an e-mail.