Documents: Interior officials thought Utah national monument was boon to tourism before shrinking it

Based on outside research, "it is reasonable to conclude that visitation would be less if the lands had not been designated as a monument," officials with the Interior Department's Bureau of Land Management wrote in a May 2017 memo. They also warned that "more vandalism would have likely occurred without Monument designation," and that one region of the monument "contains a plethora of paleontological specimens: twelve new dinosaur species have been discovered since designation."

The memos and emails show the inner workings of the team assisting Interior Secretary Ryan Zinke with the monument review, which resulted in Trump's December decision to cut Grand Staircase by nearly 45% and Bears Ears National Monument by more than 80%. The documents were first reported on Monday by The Washington Post.

The documents also show an official leading the review effort eliminating language from a document he believed "undercuts the case."

The decision on Grand Staircase and Bears Ears balanced "wanting to protect these objects of historic or scientific interest while ensuring public access to public land," Zinke wrote at the time in a CNN.com op-ed.

Some of the pro-monument information came to light because the department, apparently accidentally, posted the documents online earlier this month without redactions, according to the Center for Western Priorities, which shared the records with CNN.

Freedom of Information Act reviewers at the department had proposed withholding from public view some of the information on tourism and historical artifacts because it could be "possibly revealing NM (national monument) reviewing strategy," according to notes attached to the documents.

"These documents show that Secretary Zinke was warned very clearly in no uncertain terms that there was no way to protect the cultural and historical artifacts inside Grand Staircase-Escalante and Bears Ears without a monument designation," Aaron Weiss of the Center for Western Priorities told CNN. He said the information slated for redaction falls outside of the governments limits, and "they don't have any right to redact facts."

The Interior Department did not immediately respond to a request for comment on Monday.