Topeka ? (AP) The federal government still underestimates the risk of a planned biosecurity lab in Kansas releasing a dangerous animal disease, and an assessment earlier this year suggesting minimal danger is seriously flawed, an independent report said Friday.

The report from the National Research Council marked the second time in two years that the advisory group has questioned the U.S. Department of Homeland Security’s evaluation of the safety of the National Bio- and Agro-Defense Facility in Manhattan, Kan. The $1.14 billion lab would replace an aging lab on Plum Island, N.Y., and research contagious pathogens that could threaten the nation’s food supply.

In the new report, the group found that the department’s assessment earlier this year overestimated the danger posed by tornadoes and earthquakes but underestimated the potential risks of a disease being released by human error. The group said the DHS sometimes relied on “questionable and inappropriate assumptions” in its evaluation.

“Because a pathogen release from the NBAF could have devastating agricultural, economic, and public health consequences, a risk assessment that reaches inappropriate conclusions could have substantial repercussions,” Gregory Baecher, a University of Maryland engineering professor and chairman of the report-compiling committee, said in a statement.

Federal and Kansas officials maintain the lab, located near Kansas State University, will pose no real threat to people or animals in the area. Even with the latest National Research Council report, U.S. senators from Kansas and Missouri pressed U.S. Homeland Security Secretary Janet Napolitano to release $90 million in federal funds to continue work at the site.

Sens. Pat Roberts and Jerry Moran of Kansas, both Republicans, and Sens. Roy Blunt and Claire McCaskill of Missouri, a Republican and a Democrat, respectively, said the facility will be “the safest laboratory built of its kind to date.” Project supporters had hoped it would be operating by 2018.

“The risk of not moving forward with NBAF is a risk the American people should not have to accept,” they wrote in a letter to Napolitano that was also released Friday. “Academic and theoretical discussions of potential and unknown risks are important but should not hinder your department from taking action to address bio and agro-defense at the national level with NBAF.”

The council is an arm of the National Academy of Sciences, a private nonprofit group that advises the federal government. In 2010, based on Homeland Security’s own data, the council determined there was a 70 percent chance of an accidental release of foot-and-mouth or another dangerous disease leading to an outbreak outside the lab during the facility’s 50-year lifespan.

Then, a Department of Homeland Security assessment in March — based on revised designs — said the risk was about one-tenth of 1 percent. The evaluation buoyed Kansas officials, who have worried about resistance in Congress to continued funding for the project. They see the lab, with several hundred high-paying jobs, as an engine of economic growth and the anchor for an emerging biosciences industry.

In Friday’s congressionally mandated report, the National Research Council called the March assessment “technically inadequate in critical respects.” For example, it said a conclusion that the risk of human error for releasing a disease was 1-in-200 or lower for highly skilled workers “seems to have been arbitrarily selected and indiscriminately applied.”

However, the council said the department’s assessment in March was superior to the one in 2010, which prompted the first critical council report.

U.S. Rep. Tim Bishop, a New York Democrat whose Long Island district includes Plum Island, said the latest report underscores the concerns of him and others about the planned lab’s safety.

“The report bolsters my case that not one more taxpayer dollar should be appropriated to build this billion-dollar boondoggle,” Bishop said in a statement.

The Kansas and Missouri senators said in their letter to Napolitano that the lab is a “critical asset for our country” and delaying work on it will increase costs.

“More importantly, delays result in an increased risk on our nation’s security,” they wrote.

— Associated Press Writer Frank Eltman, in Garden City, N.Y., also contributed to this report.