The price tag: between $63 million and $98 million annually in federal, state and local funding.

But some lawmakers and educators questioned the legitimacy of the audit because the economic impact of undocumented workers - what they generate in income, sales and other taxes - was not included.

The report, "A Review of the Public Education Costs of Undocumented Children," estimated that there are between 11,000 and 17,000 undocumented students statewide, making up roughly two to three percent of Utah's student population.

It costs roughly $100 to $500 more per year to educate an undocumented student in Utah beyond the average per-pupil cost, said auditor Tim Osterstock, who oversaw the report.

That difference between the estimated undocumented student cost of $5,440 and the $5,140 per-pupil average came down to extra costs associated with English-learning and low-income programs, state officials said.

The audit comes against a backdrop of continuing attempts by some lawmakers to reduce, if not eliminate services and benefits to undocumented residents. One perennial target is resident college tuition for undocumented students.

Sen. Margaret Dayton, R-OremÂ, who requested the audit in January during the 2007 legislative session, called the report "very helpful" because Utahns need to know how much it costs to educate undocumented students and lawmakers are responsible for making sure education is adequately funded.

Dayton, who chairs the Senate's education committee, said state and local governments should not have to absorb the cost of a failed federal immigration policy, calling the education of undocumented students an "unfunded federal mandate."

She declined to say whether she thinks undocumented students have the right to a public education. But Dayton did say the state might have to look at increasing the state income tax to underwrite the costs of undocumented students.

But Democratic legislative leaders were quick to find fault with the audit.

Senate Minority Leader Mike Dmitrich, D-Price, and House Minority Leader Ralph Becker, D-Salt Lake City, asked whether the report included how much undocumented immigrants contribute in state revenue or included their economic impact in Utah.

"We're really only getting one part of the equation," Becker told members of the Legislative Management Committee Tuesday.

Legislative Auditor's office staffers said they did not look into those questions because they were not asked to.

The report also will be presented to other legislative committees.

During the past legislative session, Sen. Scott McCoy, D-Salt Lake City, called for a state study on the economic impact of undocumented immigrants, but it didn't go anywhere.

McCoy said the new report is purposely not balanced because there are people who want to "demonize" undocumented immigrants and ignore their contributions. He said he doesn't "see how the report accomplishes anything," unless some Utah lawmakers want to stop educating undocumented students.

James Yapias, a Utah educator, agreed, calling the report ''bothersome.''

"If they're going to point out the cost, they also have to point out the contributions," he said.

Anti-illegal immigration activists called the audit a good first step.

Jeff McNeil, chairman of the Utah-based Constitution Coalition, said the report is "fine but it doesn't go far enough." He said state officials should also look into the impact of undocumented students on class size and time needed by the teacher for help.

"That's an additional cost that can't be accounted for in dollars but it impacts the education of the rest of our students," McNeil said.

In 2005, there were an estimated 75,000 to 100,000 undocumented immigrants in Utah. Schools are not allowed to ask for a student's or family's immigration status under federal law.

jsanchez@sltrib.com