The overall environmental cleanup strategy at Paducah is based on taking near-term actions to control or eliminate ongoing sources of contamination along with continued investigation of other potential sources. DOE is currently working with the Kentucky Department for Environmental Protection and the United States Environmental Protection Agency, Region 4, to further define projects sequencing, while optimizing resources and utilizing a risk-based approach, to ensure timely environmental cleanup and minimize workforce impacts.
The PGDP annual Site Management Plan outlines the approach for achieving cleanup under the Federal Facilities Agreement between DOE, Kentucky, and EPA. Priorities for reducing risks are established as early as possible. Based on priorities, cleanup actions are divided into units, called operable units (OUs), which are grouped by the effected material (media) or activities—i.e., Groundwater OU, Surface Water OU, Soils OU, Burial Grounds OU, and Decontamination and Decommissioning (D&D) OU.
The cleanup scope is associated with these media-specific OUs begun before shutdown of the Gaseous Diffusion Plant. The media-specific OUs were established by assessing risks for each source area at the site. This process included looking at the type and amount of the contaminant, how the contaminant is released, and whether exposure could occur based on current and possible future use of the PGDP site.
Groundwater Operable Unit
Groundwater is the water found below the surface of the land and contained in spaces in saturated geologic media (sand, gravel). Groundwater is the source of water found in wells and springs. The Groundwater OU is using sequenced response actions designed to accomplish the following goals:
- Prevent human exposure to contaminated groundwater;
- Prevent or minimize further movement of contaminant plumes;
- Prevent, reduce, or control contaminant sources contributing to groundwater contamination; and
- Restore the groundwater to its beneficial uses wherever practicable
Burial Grounds Operable Unit
A burial ground is a disposal site for radioactive waste materials that uses earth as a shield. The Burial Grounds OU is grouped into more manageable subprojects called Solid Waste Management Units (SWMU). The Burial Grounds OU uses the CERCLA process to accomplish the following goals:
- Address sources of groundwater contamination;
- Protect industrial workers from exposure to waste and contaminated soils; and
- Treat or remove potentially harmful wastes wherever practicable.
Surface Water Operable Unit
Surface Water is all water naturally open to the atmosphere (rivers, lakes, reservoirs, streams, impoundments, seas, estuaries, etc.) and all springs, wells, or other collectors that are directly influenced by surface water.
The Surface Water OU is using sequenced cleanup and removal actions designed to accomplish the following goals:
- Prevent human exposure to contaminated sediments presenting an unacceptable risk to on-site workers and off-site recreational users of surface water;
- Prevent or minimize further off-site movement of contaminated sediments and surface water;
- Reduce, control, or minimize contaminant sources contributing to sediment and surface water contamination; and
- Evaluate and select long-term solutions for off-site surface water contamination to protect recreational users and ecological receptors
Soils Operable Unit
Soils are the particles of mineral and/or organic matter from the earth’s surface that are located outdoors, or are used indoors to support plant growth.
The Soils OU is using cleanup and removal actions designed to accomplish the following goals:
- Prevent human exposure to contamination presenting an unacceptable risk;
- Prevent or minimize further off-site migration; and
- Reduce, control, or minimize contaminated soil hot spots contributing to off-site contamination.
Decontamination & Decommissioning Operable Unit
Decontamination is the reduction or removal of contaminated radioactive material from a structure, object or person. Decommissioning is the process of removing a nuclear facility from service.
The D&D OU will use the CERCLA removal action process to administer decommissioning activities of excess buildings (i.e., inactive with no reuse potential) that have a known or potential release of contamination to the environment. The primary objective for this OU is to minimize or eliminate the potential threats to health and the environment caused by the potential uncontrolled release of hazardous substances from contaminated structures and to reduce long-term surveillance and maintenance costs.