US NRC’s uranium recovery decommissioning program and non-military radium program

Michael Norato (US NRC) presented.

The regulation of nuclear sites in the US comes under the remit of the NRC, DoE and EPA. The NRC ensures adequate protection of public health and safety, common defence and security, and protection of the environment in the use of radioactive materials at nuclear power, research, test and training reactors as well as medical, academic and industrial facilities. The NRC is also

responsible for ensuring safety with regard to the transport, storage and disposal of nuclear materials and waste. A further responsibility is the development of regulations for the safe use and remediation of radioactive materials at NRC licensed sites.

In the US, laws are enacted through code of federal regulations. NRC guidance and regulations then fall below the code of federal regulations, and ensure compliance with the overall regulations and laws. The main acts and regulations relating to legacy sites in the US are the:

• Atomic Energy Act of 1954 (as amended), the Energy Reorganization Act of 1974 (as amended);

• Uranium Mill Tailings Radiation Control Act of 1978;

• Nuclear Waste Policy Act of 1982, as amended;

• Low-Level Radioactive Waste Policy Amendments Act of 1985;

• National Environmental Policy Act of 1970; and

• Title 10 of the Code of Federal Regulations (10 CFR).

All acts are subject to the National Environmental Policy Act that requires the preservation of historic sites and important species.

Within the Uranium Control Act, two types of site are recognised; those that were inactive prior to the act (Title 1 sites) and those that were licensed by the NRC in or after 1978 (Title 2 sites). The owner of Title 1 sites may no longer exist whereas Title 2 sites have existing licensees. All 22 Title 1 sites have been transferred to the DoE, resulting in the situation whereby one regulator is

responsible for controlling another. Four of the Title 1 sites are located on the Navajo Nation, which is native American territory and there are therefore a number of sensitivities that must be considered. Of the 17 Title 2 sites, 11 are currently undergoing decommissioning and 6 have been transferred to the DoE.

Decommissioning standards for sites have been set by code of federal regulations. For soil, an activity concentration of 5 pCi/g averaged over the first 15 cm applies with an activity

concentration of 15 pCi/g averaged over 15 cm applying to the next 15 cm of soil. For radon, the standard applied is 20 pCi/m²/s and for groundwater, the lower of background or maximum contaminant levels apply, although alternate concentration limits can be proposed where these targets are not achievable, but they are subject to approval by the NRC.

For Title 1 sites, the EPA is responsible for establishing standards for clean-up and disposal for contaminated material and the DoE is responsible for identifying and remediating all sites to meet the EPA standards and for remediating properties in the vicinity of Title 1 sites. The NRC then evaluates the remediation plans and ensures that remediation has been adequately completed.

The DoE is the long-term site custodian under NRC general license.

For Title 2 sites, the EPA is again responsible for establishing standards for clean-up and disposal of contaminated material. The NRC (or Agreement State²) is then responsible for reviewing license applications, issuing licenses, conducting inspections and overseeing decommissioning. The NRC also reviews and approves DoE’s long-term surveillance plans, approves Agreement State license termination and terminates specific licenses. The DoE again becomes the long-term site custodian under NRC general license.

To date, all 22 Title 1 sites have had surface remediation works completed. Groundwater

remediation continues at some of the sites. It has not been feasible to achieve background levels at 3 sites and, as such, alternative concentration levels have been approved by NRC. Of the 6 Title 2 transferred to DoE, all have had surface remediation works completed and groundwater

remediation works have also been undertaken with alternative concentration levels having been applied at 3 sites that are subject to continued monitoring. No groundwater monitoring is

undertaken at 3 other sites. Of the 18 remaining Title 2 sites that are undergoing decommissioning works, 11 are NRC licensed and 7 are Agreement State licensed.

The locations of Title 1 and Title 2 sites are illustrated in Figure 21. The majority of sites are located in or near the Rocky Mountains and particularly in the states of Colorado, Utah and New Mexico.

There is a 5-year Navajo Nation plan ongoing. The Navajo Nation territory was the location of some of the first uranium deposits that discovered in the US and 4 disposal/processing sites are located in this region (Figure 22). Tailings have been removed from the Monument Valley site and works are currently ongoing to remediate the groundwater through the use of phytoremediation techniques. The tailings from the Monument Valley site were moved to the Mexican Hat disposal site where they have been placed in a disposal pit and covered to minimise radon emission. The Shiprock disposal site in New Mexico is comprised of a coarse rock pile of tailings that has been fenced off. This site remains under active control.

A further recent project has focussed on a mill site and mine at Church Rock, New Mexico that is close to the boundary with Navajo Nation. The Navajo Nation has agreed for mine waste to be removed and placed on top of mill tailings at the site. Work is ongoing to investigate the potential impacts of this with regard to groundwater movement and the potential for increased pollution of the area. If this work does go ahead, an amendment of the current NRC license will be required.

The main challenges to the ongoing uranium decommissioning program relate to the large extent of the program and determining long-term care fees. Licensees are meant to provide financial assurance to the DoE to fund the long-term maintenance of sites, but experience has shown that the funds are not sufficient to cover the remediation programs required. As such, the DoE has taken over a number of sites and there are insufficient funds available to appropriately maintain the sites. A further challenge relates to exceedances of alternate concentration limits. These limits are derived from groundwater modelling. However, experience shows that, following transfer of sites to long-term care, exceedances have occurred that have required additional remediation measures that have significantly increased the costs associated with maintaining these sites, compared with original estimates. Budget constraints faced by the NRC also limit site inspections.

2 38 Agreement States have been approved by the NRC as being responsible for decommissioning sites.

Figure 21. Location of US Title 1 and Title 2 sites.

Figure 22. Location of the Navajo Nation territory and associated processing and disposal sites.

In terms of radium, the 2005 Energy Policy Act stipulates that the NRC has the regulatory authority over all past, present and future discrete sources of Ra-226 and any contamination associated with these sources. There are two parts to the radium program. Military bases contaminated with

radium (especially naval bases) require the EPA and NRC to work together with the NRC having jurisdiction for sites that do not fall within the National Priorities List. The EPA has jurisdiction for sites on this list. The other part of the program relates to non-military sites.

Radium was historically used in a range of consumer products such as shoe polish, make up and clocks and many of the facilities that manufactured these products now require remediation, such as the former Waterbury Clock Company facilities. Radium was used in the manufacture of clocks from 1919 to the 1930’s resulting in the residual contamination of the company’s building, both with radium and asbestos. The NRC is coordinating the clean-up of the site with the EPA under the EPA’s brownfield program. Great Kills park is another Ra-226 contaminated site. The park was built on a former landfill and radium needles from hospitals and other contaminated products have been discovered. Currently around 265 acres of the park are closed to the public. The NRC is coordinating with the park owner (the US National Park Service) to characterize the site and undertake clean-up activities. With the awareness of these sites, the NRC has initiated a program to identify other sites that may have historical radium contamination. More than 30 sites have so far been identified and the program is ongoing.

5.2 Experience of Ukraine in implementing rehabilitation and