Environmental Impacts
At the time of the construction of the PGDP, significant state and federal environmental regulations did not exist, at least certainly not to the extent that they do in the present. As a result, commonly accepted standard operating procedures used in managing or disposing of potentially toxic chemicals where much different and more relaxed than today. As a result, significant environmental contamination occurred at the site. For a detailed list of the types of toxic chemicals present at the site one should consult the USEPA Superfund Website at here.
Much of the environmental contamination that occurred at the site resulted from the way in which the toxic chemicals were handled and disposed. For example, the improper disposal of fluids resulting from the cleaning of metal parts of the cascade resulted in significant groundwater contamination. For example, TCE, a chemical used to degrease equipment, was released into the ground which then resulted in several massive groundwater plumes. Similarly, the release of such cleaning fluids also carried with them other toxic chemicals into the ground such as a radioactive metal (element) called Technitium 99. This has also resulted in a significant groundwater contamination plume of Technitium 99. It fact, it was the detection of Technitium 99 in residential drinking water wells around the site that first alerted officials to the presence of significant groundwater contamination at the PGDP site.
In addition to these chemicals, other chemicals such as PCPs and heavy metals (including uranium) have also been found at the site, both in the soils within the security area of the site as well as in the streams and stream sediments outside of the plant boundary. Some of these chemicals have also been found in elevated concentrations in different forms of wildlife that inhabit the Kentucky Wildlife Management Area.
TCE was widely used as a cleaning solvent at PGDP from the time the plant was constructed until June 30, 1993. During the period from December 1962 to September 1988, the largest volume of TCE used in any month was approximately 15,000 gallons (56,781 L) in August 1977 (CH2M HILL 1991). Environmental releases of TCE have occurred through spills, leaks, vapor emission, and discharges to soils, surface water, and groundwater (DOE 1995).
General Waste Characterization
The different types of wastes that have been found at the PGDP may be grouped or characterized on the basis of the different state or federal regulations that govern their management and disposal. Generally, wastes can be characterized as either hazardous wastes or non-hazardous wastes. Hazardous wastes can further be subdivided into three categories: RCRA wastes, TSCA wastes, or DOE (radioactive) wastes. When two or more types of hazardous wastes are mixed together, they are generally called “mixed wastes.”
I. Non Hazardous Wastes
Non-Hazardous Wastes – wastes that are governed by the Kentucky
II. Hazardous Wastes
- RCRA Wastes – wastes that are covered by the Resources Conservation and Recovery Act of 1983
- TSCA Wastes – wastes that are governed by the Toxic Substances Control Act of 1977
- DOE Wastes – wastes that are produced by DOE and are governed by the Nuclear Regulatory Commission. DOE wastes may be further subdivided into low level (radioactive) wastes, LLW; high level (radioactive) wastes, HLW; and transuranic wastes (TW). Any HLW or TW found at Paducah will have to be shipped to one of the DOE waste facilities outside of Kentucky.
Estimates of the Volumes of various Types of Wastes at the Paducah Gaseous Diffusion Plant*
Waste | LLW (yd3) | LLW/RCRA (yd3) | LLW/RCRA/TSCA (yd3) | LLW/TSCA (yd3) | RCRA (yd3) | TSCA (yd3) | Nonhazardous Solid Waste (yd3) | Total (yd3) |
Asbestos | 3700 | 0 | 24,800 | 0 | 0 | 4,000 | 1,000 | 33,500 |
Concrete | 377,400 | 800 | 0 | 0 | 0 | 0 | 393,300 | 771,500 |
General Construction Debris | 425,800 | 2,900 | 0 | 0 | 0 | 2,900 | 235,400 | 667,000 |
Other Dry Solids | 46,000 | 100 | 5,300 | 200 | 500 | 700 | 4,200 | 57,000 |
Scrap Metal | 407,800 | 200 | 0 | 0 | 0 | 3,700 | 68,800 | 480,500 |
Soil | 1,286,300 | 29,100 | 0 | 0 | 16,100 | 1,700 | 376,300 | 1,709,500 |
Total | 2,547,000 | 33,100 | 30,100 | 200 | 16,600 | 13,000 | 1,079,000 | 3,719,000 |
*Note: these are estimates of the volume of wastes that can be expected to be generated once the PGDP is torn down. These volumes do not include any existing wastes that may be buried in existing burial grounds on the site or landfills off of the site.
Detailed Descriptions of Wastes
I. Non-Hazardous Wastes
If wastes do not meet any of the three basic hazardous waste categories (i.e. RCRA, TSCA, or DOE), then they are considered nonhazardous solid waste (as opposed to hazardous wastes). Nonhazardous solid waste disposal and recycling is regulated on a state level through a formal permitting process.
II. RCRA (Hazardous Wastes)
RCRA (Resource Conservation and Recovery Act) gives EPA the authority to control hazardous waste from the "cradle-to-grave." This includes the generation, transportation, treatment, storage, and disposal of hazardous waste. RCRA also set forth a framework for the management of non-hazardous solid wastes. The 1986 amendments to RCRA enabled EPA to address environmental problems that could result from underground tanks storing petroleum and other hazardous substances. RCRA wastes have been divided into two main categories: Listed Wastes and Characteristic Wastes. Each of these are explained below:
A. Listed Wastes
Wastes are listed as hazardous because they are known to be harmful to human health and the environment when not managed properly, regardless of their concentrations. EPA has studied and listed as hazardous hundreds of specific industrial wastestreams. These wastes are described or listed on four different lists that are found in the regulations at Part 261, Subpart D. These four lists are:
1. The F list - The F list designates as hazardous particular wastes from certain common industrial or manufacturing processes. Because the processes producing these wastes can occur in different sectors of industry, the F-listed wastes are known as wastes from non-specific sources. The F list is codified in the regulations at 40 CFR §261.31.
2. The K list - The K list designates as hazardous particular wastestreams from certain specific industries. K-listed wastes are known as wastes from specific sources. The K list is found at 40 CFR §261.32.
3-4. The P list and the U list (Discarded Commercial Chemical Products) - These two lists are similar in that both list pure or commercial grade formulations of certain specific unused chemicals as hazardous. Both the P list and U list are codified in 40 CFR §261.33. A P or U waste code may be applicable, provided that the material is an unused commercial chemical product (CCP). A CCP is a substance that consists of the commercially pure grade of the chemical, any technical grades of the chemical, and all formulations in which the chemical is the sole active ingredient (§261.33(d)).
B. Characteristic Wastes
Even if the wastestream does not meet any of the four listings explained above, it may still be considered a hazardous waste if it exhibits one of four different characteristics: ignitability (D001), corrosivity (D002), reactivity (D003) and toxicity (D004-D043). Each of the categories are summarized as follows:
1. Ignitability - Ignitable wastes create fires under certain conditions or are spontaneously combustible, or have a flash point less than 60 °C (140 °F). The characteristic of ignitability is found at 40 CFR §261.21.
2. Corrosivity - Corrosive wastes are acids or bases (pH less than or equal to 2 or greater than or equal to 12.5) that are capable of corroding metal containers, such as storage tanks, drums, and barrels. The characteristic of corrosivity is found at 40 CFR §261.22.
3. Reactivity - Reactive wastes are unstable under "normal" conditions. They can cause explosions, toxic fumes, gases, or vapors when mixed with water. The characteristic of reactivity is found at 40 CFR §261.23.
4. Toxicity - Toxic wastes are harmful or fatal when ingested or absorbed (e.g., containing mercury, lead, etc.). When toxic wastes are disposed of on land, contaminated liquid may drain (leach) from the waste and pollute ground water. Toxicity is defined through a laboratory procedure called the Toxicity Characteristic Leaching Procedure (TCLP). The toxicity characteristic is found at 40 CFR §261.24.
Generators are responsible for characterizing their waste and hazardous and must determine whether a waste exhibits a characteristic by either testing or applying knowledge of the hazardous waste characteristic of the waste (§262.11).
In addition to federal RCRA hazardous waste identification rules we have outlined, most states are authorized to operate their own hazardous waste programs and may have more stringent rules than those of the federal hazardous waste management program. For instance, a state may impose more stringent regulations for hazardous waste identification or identify state-specific hazardous wastes.
III. TSCA Wastes
The Toxic Substances Control Act (TSCA) became law on October 11, 1976 to became effective on January 1, 1977, except Section 4 (f) which took effect two years later. The Act authorized EPA to secure information on all new and existing chemical substances, as well as to control any of the substances that were determined to cause unreasonable risk to public health or the environment. Congress later added additional titles to the Act, with this original part designated at Title I - Control of Hazardous Substances. Further information on the titles is as follows:
Title I - Control of Toxic Substances: This title includes provisions for testing of existing chemical substances and mixtures, regulation of hazardous chemical substances and mixtures, manufacture and processing notices, in addition to managing imminent hazards and reporting and recordkeeping requirements. As an example, the control and regulation of PCBs falls under this part of TSCA.
Title II - Asbestos Hazard Emergency Response: This was added by the Asbestos Hazard Emergency Response Act (AHERA) (P.L. 99-519), passed on October 22, 1986. This amendment established asbestos abatement programs in schools. AHERA provides for the promulgation of federal regulations requiring periodic asbestos inspections and reinspections and the necessary response actions in schools. It also requires the EPA Administrator to made determinations of the extent of danger to human health posed by asbestos in public and commercial buildings and the means to respond to the dangers. AHERA was later amended by the Asbestos School Hazard Abatement Reauthorization Act (ASHARA) (P.L. 101-637) in 1990. Under this amendment, accreditation requirements were added for persons conducting asbestos inspections and abatement activities in schools, commercial buildings and public buildings.
Title III - Indoor Air Radon Abatement: In October 1988, Congress added a third title to TSCA regulating radon with the Radon Reduction Act (PL 100-551). This amendment was to assist states in responding to the human health threats posed by exposure to radon. EPA was required to publish an updated citizen's guide on the health risks of radon, and to perform studies of the radon levels in government buildings and schools.
Title IV - Lead Based Paint Exposure: In October 1992, TSCA was again amended to add the Lead-Based Paint Exposure Reduction Act (PL 102-550). This legislation was to reduce environment exposure to lead contamination and prevent the adverse health effects caused by it. Exposure of children was the primary concern. Provisions of the Act included exposure studies, determination of lead levels in products, establishing state programs for monitoring and abatement, and training and certification requirements for lead abatement workers.It should be noted that under earlier statutes, EPA had the authority to control toxic substances only if damage was caused. Under TSCA, the effects on public health and environmental of all new chemicals had to be reviewed before they could be manufactured for commercial purposes.
IV. DOE Wastes
Department of Energy Mixed-Waste
DOE facilities primarily produce and/or stores three types of mixed-waste: 1) low level wastes (LLW), high level wastes (HLW), and Transuranic wastes (TW).
A. Low Level Waste
DOE's low-level waste (LLW) is generated, projected to be generated, or stored, at 37 DOE sites in 22 states. It comes from research, development, and production of nuclear weapons. Waste management activities will require management of an estimated 226,000 cubic meters (m3) of LLW over the next 20 years.
B. High-Level Waste
DOE's high-level waste (HLW) is radioactive waste which is liquid prior to treatment and comes from reprocessing spent nuclear fuel and irradiated targets from reactors. Some of its elements will remain radioactive for thousands of years. Because it contains highly corrosive, organic, or heavy metal components that are regulated under RCRA, this HLW is considered a mixed-waste.
DOE's HLW is stored in large tanks at three locations:
- Hanford, Washington (50,000,000 gallons)
- Idaho National Laboratory, Idaho (900,000 gallons)
- Savannah River Site, South Carolina (36,000,000 gallons)
DOE has treated some of the HLW by processing it into a solid form (e.g. borosilicate glass) that is not readily dispersible into the air or leachable into the ground or surface water. This treatment process is called vitrification. Between 1996 and 2001, the approximately 660,000 gallons of highly radioactive liquid waste stored at West Valley was vitrified. The vitrification process will ultimately generate approximately 29,000 canisters for disposal in a geologic repository. Currently, Yucca Mountain, Nevada, has been identified as the site for a potential geological repository.
V. Transuranic Waste
DOE transuranic waste (TW) is waste that has radioactive elements heavier than uranium. The radioactivity in the TW must be greater than 100 nano Curies per gram (nCi/g). The principle hazard from TW is alpha-particle radiation through inhalation or ingestion.
TW is primarily generated from nuclear weapons fabrication, plutonium-bearing reactor fuel fabrication, and spent fuel reprocessing. The amount of TW generated by entities other than DOE is negligible. Approximately 55% of DOE's TW waste is mixed-waste (that is, it also has hazardous wastes mixed in with it). Approximately 1,500 m3 of MTW from Rocky Flats, Colorado has been retrieved for disposal and the site is closed. MTW is currently being retrieved for disposal at five DOE sites:
- Hanford, Washington (3,000 m3)
- Idaho National Laboratory (38,000 m3)
- Los Alamos National Laboratories, New Mexico (8,000 m3)
- Oak Ridge National Laboratory, Tennessee (1,500 m3)
- Savannah River Site (5,000 m3)
DOE disposes defense-related TR at the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico. Before DOE can dispose of waste at the WIPP, it must demonstrate that the waste has been characterized in compliance with the EPA regulations at 40 CFR 194 and meets EPA's radioactive waste disposal standards (40 CFR 191). EPA approved DOE's initial compliance certification application (CCA) in May 1998. DOE must submit a Compliance Recertification Application (CRA) every five years to demonstrate that the WIPP continues to comply with EPA's TW waste disposal standards. DOE's first recertification was approved by EPA in March 2006.