More than $73 million will be funneled toward road and water infrastructure projects as part of a settlement between the U.S. Department of Energy and the state over a radiation leak that forced the indefinite closure of the federal government's troubled nuclear waste dump in southern New Mexico.

The agreement, announced by Republican Gov. Susana Martinez and state Environment Secretary Ryan Flynn, follows months of tense and at times seemingly stalled negotiations.

The settlement is the largest in DOE's history, Flynn said, noting that the agency needed to be held accountable for putting New Mexicans at risk.

"We have a shared responsibility to protect the citizens that work at these facilities as well as the communities that host these facilities," Flynn told The Associated Press.

The state initially levied more than $54 million in penalties against the agency and its contractors for numerous permit violations at Los Alamos National Laboratory and the Waste Isolation Pilot Plant that resulted in the repository's shutdown.

A drum of waste was inappropriate packed with incompatible ingredients at Los Alamos and shipped to the repository. A chemical reaction ensued and on Feb. 14, 2014, radiation escaped and alarms at the facility were triggered.

Federal investigators determined the mishap could have been prevented. Poor management at multiple levels, lapses in safety and a lack of proper procedures combined to cause the radiation release, they said in a report this month.

The DOE and the head of the Los Alamos lab say they're working on corrective actions to ensure greater oversight of the handling and disposal of radioactive waste.

The settlement with the state is contingent on DOE following through with those corrective actions.

Watchdogs and community groups voiced concerns when the state first announced the penalties in December, saying they didn't want the DOE to pay the fines with money meant for operations and environmental cleanup work at Los Alamos and WIPP.

"We listened very carefully to what we heard from the communities," Flynn said, referring to both state and federal negotiators.

DOE initially contested the fines, and Flynn threatened even more penalties when talks seemed to break down. It took a couple of meetings and many calls, some of which included congressional members, to focus the negotiations.

Most of the infrastructure spending outlined in the settlement is expected to come from the bonuses and other incentive pay DOE withheld from Los Alamos and WIPP contractors in the wake of the radiation release. The difference will be reassigned from other DOE sites.

More than half of the settlement funds will pay for repairs and improvements for roads in southeastern New Mexico that are used to haul waste to WIPP. Another $12 million will go to roads in and around Los Alamos.

Nearly $20 million will go toward water projects in Los Alamos, from replacing old drinking water lines to monitoring and controlling storm runoff from the canyons surrounding the lab.

There's also funding for a new emergency operations center in Carlsbad and training for first responders and mining rescue teams.

Nearly $3 million will be used for a triennial review of all operations at the lab and the repository to ensure state and federal requirements are being met and policies are being followed.