The Department of Homeland Security has approved a site at Kansas State University for a $450 million lab to study livestock diseases and some of the world's most dangerous biological threats.

DHS released its final record of the approval Monday, confirming a decision announced in December to build the National Bio and Agro-Defense Facility at the Manhattan, Kan., campus to replace an aging lab at Plum Island, N.Y.

Sites in Georgia, Mississippi, North Carolina and Texas were also considered for the new lab, where animal diseases and other potential bioterrorism threats will be researched.

The federal agency said factors in its decision included the proximity of the site to Kansas State's research labs and its colleges of agriculture and veterinary medicine.

Kansas Sen. Sam Brownback, a member of the Senate Appropriations Committee, said he will work to ensure the project is fully funded. The state has agreed to provide more than $105 million in infrastructure improvements at the site to cover additional costs.

"This is great news. NBAF is a great win for Kansas and Kansas is a great win for NBAF," said Brownback, a Republican.

The laboratory is to be built on 59 acres at Kansas State near the Biosecurity Research Institute, where similar activities are conducted on plant and animal diseases.

University officials have said that the lab could conduct a portion of the research that will be done at NBAF until that facility is completed, which is expected to be by 2015.

Republican Sen. Pat Roberts called the decision "one of the most significant investments to the Kansas economy in state history."

"With this new lab, Kansas will cement its reputation as the nation's leader in plant and animal health research and the biosciences," Roberts said. "We will reap the benefits of a cutting edge industry while protecting the nation's food supply and agricultural economy for years to come."

Critics of NBAF raised concerns about the safety of people living near the lab, including in on-campus housing. They also said thousands of head of livestock in the region would be vulnerable if pathogens escaped from the facility.

Officials in Texas and Mississippi have threatened litigation over the decision.

Last week, Texas Gov. Rick Perry called the selection process unfair because his state's legislators weren't in session in 2008 and unable to consider a financial package to augment the state's bid.

Mississippi Gov. Haley Barbour said last month when the initial recommendation was made that the process was flawed and that his state should have been awarded the project.