Federal Remediation Branch The Federal Remediation Branch works with EPA and, when appropriate, the Department of Defense (DOD) to investigate, assess and remediate sites where uncontrolled and unregulated hazardous wastes have been or may be released into the environment. Once discovered, sites are placed on EPA's CERCLA inventory (CERCLIS) and assessed to determine their relative risk to public health and the environment. CERCLIS sites are screened for the National Priorities List (NPL) using criteria set out in EPA's Hazard Ranking System (HRS). Branch staff investigate and sample sites, then use the HRS to evaluate those sites. Evaluation of these sites is based on the likelihood of hazardous substance release, characteristics of wastes on site, and their potential impacts on target populations and sensitive environments should contaminants migrate through air, surface water, groundwater or soil exposure pathways. Site assessment leads the branch to refer some sites to EPA for emergency actions to address imminent threats to human health or the environment and also refer other sites to the Superfund Section’s Inactive Hazardous Sites Branch for cleanup under that program. For the small percentage of evaluated sites that qualify to be listed on the National Priority List or are determined to be of NPL caliber, the Federal Remediation Branch provides both oversight and technical guidance to the EPA for site cleanup. Sites on the National Priorities List (NPL) are eligible for long-term remedial action financed by a federal trust fund with a state cost share or by potentially responsible parties (PRP). When the federal trust fund is used, CERCLA requires the state to provide assurances, including payment of 10 percent of the cost of remedial actions and 100 percent of certain types of operation and maintenance (O&M). The Federal Remediation Branch manages the operation and maintenance of NPL sites that are returned to North Carolina by EPA after the NPL remediation process has been completed. The Federal Remediation Branch also works with the DOD to investigate and remediate sites on DOD installations and at non-installation sites once used by DOD (Formerly Used Defense Sites or FUDS). The DOD finances long-term remedial action at these federal military sites through the Defense Environmental Restoration Program (DERP). The North Carolina Department of Defense and State Memorandum of Agreement lists eligible DERP sites in North Carolina, and governs their cleanup by DOD in partnership with the state.