John R. Lupa Jr.
Duke Engineering and Services
580 Main Street
Bolton, Massachusetts 01740

This paper will address the Polychlorinated Biphenyl (PCB) paint disposal, sampling and quantification program at the Yankee Nuclear Power Station ("the Yankee plant") and the applicable federal regulations. In addition, this paper will describe the methodology Yankee Atomic Electric Company (Yankee) will implement in developing disposal solutions for PCB containing waste which is also radioactive, and the cost and schedule impact on decommissioning.

In December of 1996, paint samples taken from the interior surface of the Vapor Container revealed the presence of PCBs. After identifying the presence of paints containing PCBs in the Vapor Container, a site characterization was conducted to determine the nature and extent of PCB concentrations in paints throughout the plant.

The site characterization showed that dried paint containing PCB concentrations in excess of 50 ppm, the Environmental Protection Agency (EPA) threshold limit for regulation, was primarily limited to the Vapor Container. The Vapor Container structure exhibited the highest PCB paint concentrations, ranging from 30,000 ppm to 100,000 ppm. Through research Yankee discovered that PCBs at these high concentrations were used as plasticizers in paints during the 1950's through the early 1970's. Inside the Vapor Container, the majority of components and structures also showed paint containing PCB concentrations in excess of 50 ppm. Most of these components and structures at the Yankee plant are also radioactively contaminated.

PCBs are regulated under the Toxic Substances Control Act (TSCA). Currently there is no commercial facility available for disposing of solid radioactively contaminated PCB containing materials. Yankee is seeking a disposal solution for radioactive PCB waste.

Yankee is currently evaluating various disposal options for material both coated with paint containing PCBs and contaminated with radioactivity. These options include: 1) thermal destruction of PCBs via incineration and then disposing the metal portion of the material as radioactive waste and/or 2) obtaining a 10 CFR 20.2002 U.S. Nuclear Regulatory Commission (NRC) or Agreement State approval for alternative disposal of material and subsequent landfill in a TSCA-approved disposal facility. In anticipation of a disposal solution, Yankee has submitted an application to EPA for an Alternate Method of Disposal Approval (AMDA) for final remediation of metal and concrete surfaces that are coated with PCB containing paint. (The AMDA is often referred to as a permit). The AMDA process requires obtaining permission from the EPA for the removal of PCB containing paint from metal and concrete surfaces. The application includes a waste description, paint removal methods, waste storage, decontamination criteria, management of PCB containing waste, and a health and safety plan.

The Yankee plant located in Rowe, Massachusetts produced electric power for the New England region from 1960 through February 1992, when the Yankee plant was shut down for economic reasons. Subsequently, Yankee Atomic Electric Company (YAEC) began decommissioning of the Yankee plant in accordance with U.S. Nuclear Regulatory Commission regulations (10 CFR Part 50).

In December of 1996, when seven paint samples revealed the presence of PCBs taken in various areas within the Vapor Container at the Yankee plant, PCB containing paint received greater scrutiny by the Yankee Decommissioning Project. The Vapor Container is a 125 foot diameter steel sphere which housed large components such as the steam generators, pressurizer and reactor vessel. Until this time, the decommissioning of the Yankee plant had focused primarily on radiological decontamination and disposal of major components such as the steam generators and reactor vessel to the low-level waste site in Barnwell, South Carolina.

After identifying the presence of PCB containing paints within the Vapor Container, YAEC conducted a survey of the Yankee plant in January of 1997 to identify painted materials with PCB concentrations. During the survey, painted structures were listed by type (e.g, pipes, conduit, duct, steel structures, walls, floors) and paint color. Potential sampling locations were identified. Because there was a clear pattern of paint use throughout the buildings and not all the paint contained PCBs, a matrix of material types and paint colors was developed and used to guide the sampling team to the appropriate sample types in each building. Painted surfaces included pipes, conduit, duct, structural steel, block walls and concrete floors.

Over 200 wipe, paint, and concrete chip samples were collected from metal and concrete surfaces by hand scraping or wiping. The samples included all paints from the surface to bare metal or concrete to ensure all layers of substrate coatings were evaluated. The PCB concentration by Aroclor number was determined for all samples. Concrete chip samples were collected to a maximum depth of ½ inch immediately below selected paint samples to determine the extent of PCB migration into the floor surfaces. Subsequent sampling was performed to confirm results obtained during initial sampling or to determine the extent of contamination in areas with elevated PCB concentrations. Samples were collected in accordance with a plant sampling procedure and a chain of custody procedure.

A total of 34 wipe samples were taken from floors and walls throughout the primary and secondary sides of the plant. In general, the sampling results were well below the standards typically applied to surfaces after liquid PCB spill clean-up and are considered clean enough for routine human contact in an industrial setting. The EPA PCB Spill Clean-Up Policy recommends 10µg/100 cm² as the clean-up standard for high contact surfaces in industrial settings as described in 40 CFR 761.125. Only 2 of the 34 wipe samples collected indicated PCB surface contamination above this standard. These 2 samples were taken inside the Vapor Container. Subsequent air monitoring inside the Vapor Container confirmed that the PCBs were encapsulated in the paint and therefore did not pose a risk to workers.

The results of the paint samples collected at the Yankee plant indicated the Vapor Container shell (interior and exterior) paint contained PCB concentrations ranging from 30,000 ppm to 100,000 ppm. These high concentrations of PCBs found on the Vapor Container shell result from the intentional addition of PCBs to certain paints by the manufacturer during the 1950's through the early 1970's as a plasticizer. Paint on components and structures within the Vapor Container contained PCB concentrations of 100 ppm to 2,000 ppm. The remainder of the plant was generally free of PCB containing paint.

All 28 concrete chip samples taken showed minimal to no PCB migration into the floor or wall surfaces. The highest PCB concentration in concrete was less than 3 ppm for concrete chips taken to a depth of ½ an inch.

Table I summarizes the PCB sample results for surface wipes, paint chips, concrete chips and Toxicity Characteristic Leaching Procedure (TCLP).

Beginning in 1978, the Environmental Protection Agency (EPA) promulgated a series of regulations (40 CFR 761) under TSCA. This Act required the EPA to control the manufacture, processing, distribution, use, disposal, and general environmental management of PCBs. In this way, PCBs became a regulated substance, and though these regulations did not require the removal of PCBs from service earlier than would normally be the case, TSCA did regulate any dismantling of PCB items and their subsequent disposal.

In June of 1991, EPA published an Advanced Notice of Proposed Rule Making (ANPRM) under TSCA, identifying various issues associated with the current regulations that the EPA felt necessary to change. The decision to proceed with a formal rulemaking, proposed on December 6, 1994 paved the way for dealing with a variety of interpretive issues not fully addressed by the current TSCA regulations. The TSCA regulations were written primarily for PCBs in liquid form. Much of the language deals with PCB spills and the need to deal with PCB items such as transformers and capacitors. The proposed rule specifically addresses some of these non-liquid applications and even contains a section on PCBs and radioactivity.

One of the key aspects of the proposed rule that applies to dry paint containing PCBs is the option of disposing the PCB waste in a permitted non-TSCA landfill based on very low TCLP leach ability results (less than 50µg/l). This option would basically deregulate the PCB portion of the waste. Another proposal in the new rule would allow disposal on a site specific petition provided there is "no unreasonable risk of injury to health or the environment."

The ultimate objective of YAEC is to return the Yankee plant site to a "green field" in a safe and economical fashion. This means removing all structures and components and remediating the surroundings where necessary from hazardous and radiological contamination. Removing structures and components from the site sometimes requires sending the materials to licensed treatment and disposal facilities. Waste contaminated with both radioactivity and PCB is considered a TSCA "mixed waste." Currently, there is no commercial disposal facility available for radioactively contaminated PCB containing materials. Yankee has dismantled approximately 20 tons of low-level radioactive material coated with PCB containing paint. The material will be stored on site until a disposal solution is found. Nearly 1,000 tons of material scheduled for dismantlement may potentially share these mixed waste characteristics. Yankee's intent is to define a disposal solution for this waste in a manner that will have minimal impact on schedule and cost.

A more immediate goal is to obtain EPA approval under 40 CFR 761.60(e) for an "Alternative Method of Disposal" application to remove PCB containing paint from metal and concrete surfaces and store the PCB wastes on site. Removing the PCB containing paint from the substrate will minimize the amount of radiologically contaminated PCB material that is regulated by TSCA and NRC. This can only occur if the substrate (i.e. the metal or concrete from which the paint is removed), is to be identified below TSCA regulatory limits. The decontaminated substrate would then be made available for reuse, recycle, or disposal. The remaining paint residues and debris that contains both PCBs and radioactivity will remain on-site until a disposal facility becomes available.

Yankee is currently developing a formal bid specification and Requisition For Proposal (RFP), that identifies disposal needs, quantifies the amount of material that may contain both PCBs and radioactivity and outlines the scope of work. The bid specification will be sent to interested vendors for solicitation. The vendors will be asked to propose a disposal methodology, schedule, and cost. The RFP will request proposals from vendors who can thermally destroy PCBs or who can otherwise dispose of the PCB material in a licensed landfill. Yankee will evaluate and may subsequently award a contract to the successful vendor(s) whose proposal fulfills these objectives. The RFP will establish a formal mechanism to narrow down realistic disposal options.

Disposal of radioactive PCB material requires possession of an EPA TSCA permit and a NRC or Agreement State radioactive material license. It is expected that the permitting and licensing processes may take as long as three years. All potential vendors interested in disposing Yankee's waste have expressed a concern regarding the current market for the disposal of TSCA mixed waste and none of the thermal treatment facilities could meet the TSCA destruction standards without significant modifications. An indication of future income other than from Yankee is a prerequisite for these interested companies before embarking in the costly and lengthy process to obtain the necessary permits and make the appropriate equipment and procedural modifications to dispose of PCB/radioactive waste.

Another strategy Yankee is pursuing is the NRC exemption approach under provisions outlined in 10 CFR 20.2002 (or corresponding Agreement State) "Alternate Disposal Request" which would essentially "deregulate" the exceptionally low-level radioactivity in the waste. Disposal of the waste in a TSCA landfill controls the waste in accordance with the greater hazard of PCBs and therefore poses no significant radiological impact to the public. This process, however, entails several technical, regulatory, contractual, and political issues.

The cost impact associated with disposing of PCB materials from the Vapor Container has been evaluated in two basic scenarios. The first scenario assumes that there is a facility that can dispose of radiologically contaminated PCB material. This is the most significant cost unknown. Activities such as engineering, paint removal, post-sampling and waste disposal are considerably higher for scenario #1 than scenario #2 since all of the PCB containing paint would need to be removed from the substrate. The cost estimate assumes the incremental processing costs are approximately the same as the cost to process radiologically contaminated material. Table II summarizes the PCB project approximate cost estimate for the first scenario.

The second cost estimate developed for the processing of materials related to the removal of PCB containing paint is presented below in Table III. This scenario assumes that a successful 10 CFR 20.2002 NRC exemption has been obtained. A successful NRC exemption would allow the PCB containing paint to remain on the substrate, therfore, the cost of post-sampling, engineering, paint removal and waste disposal would be less costly. As described previously, the 10 CFR 20.2002 application would essentially deregulate the radioactivity in the waste. Therefore, the waste would be managed as a TSCA-only waste. There would be several disposal sites available to Yankee for such PCB waste.

The schedule for activities inside the Vapor Container has been delayed by approximately six months because of the presence of PCBs in the paint. Various activities inside the Vapor Container have ceased pending approval of the AMDA. However, the entire workforce that was once working inside the Vapor Container has been shifted to other locations throughout the site such as the Primary Auxiliary Building (PAB) and Turbine Building (TB). The PCB containing paint within the Vapor Container has had little effect on the total decommissioning schedule of the plant thus far. However, significant delays in the approval of the AMDA would impact schedule and cause Yankee to revise the impact to cost and schedule.

In 1992 it was decided to cease operation of the Yankee plant and proceed with decommissioning. The effort involved almost entirely radiological issues including the removal of low level wastes and radiologically contaminated structures until 1996. This changed with the discovery of PCB containing paint on the exterior of the Vapor Container.

Now many tasks are being performed in response to the PCB issue. Yankee is currently pursuing various options which will lead to the safe and economic disposal of all contaminated material from the site. One option that is already in process is the AMDA approach, which will allow Yankee to remove PCB containing paint from the substrate and allow the substrate to be disposed of in conventional fashion. The second option Yankee is pursuing is the process of identifying and working with a commercial facility that can properly dispose of radiological contaminated PCB materials. This could be either an approved landfill or other processor with the capability to destroy PCBs in an approved smelter. The third option is to vigorously pursue minimizing the amount of low level radioactive material by using existing NRC regulatory provisions outlined in 10 CFR 20.2002.

As more nuclear power plants plan for or enter decommissioning activities over the next several years there needs to be an emphasis placed on analyzing for mixed waste, in particular radiological PCB waste. As previously mentioned, paints that contained PCBs at high concentrations were manufactured from the 1950's through the early 1970's. Therefore, there is a high probability that most radioactively contaminated facilities built during this period face the dilemma of managing PCB waste for which no commercial disposal facility currently exists. Branches of the government such as the U.S. Navy and Energy Department have encountered similar predicaments for the management of radioactively contaminated PCB containing paints.

1. U.S. CODE OF FEDERAL REGULATIONS Volume 40, Part 761, "Polychlorinated Bi-Phenyls (PCBs): Manufacturing, Processing, Distribution in Commerce, and Use Prohibitions".
2. U.S. CODE OF FEDERAL REGULATIONS Volume 40, Part 761, "Disposal of Polychlorinated Bi-Phenyls (PCBs): Manufacturing, Processing, and Distribution in Commerce; Proposed Decision on Exemption Petitions; Proposed Rules" (December 6, 1994).
3. U.S. CODE OF FEDERAL REGULATIONS Volume 10, Part 20, "Standards For Protection Against Radiation".

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