4
Department of Energy’s Proposed Characterization Plan

This chapter describes DOE’s proposed characterization plan for RH-TRU waste. Because the plan must address EPA and NMED regulatory requirements, the characterization plan consists of two documents: a notification of proposed change to the EPA Certification (Document 1) and a Request for RCRA permit modification (Document 2). On June 28, 2002 DOE submitted Documents 1 and 2 to the respective agencies. This chapter addresses the March 2002 draft characterization plan and the main differences with the July 2001 draft.

It is the committee’s understanding that DOE will submit to EPA and NMED, along with Documents 1 and 2, a sample of completed characterization documents for three RH-TRU generator sites (Energy Technology Engineering Center, Battelle Columbus Laboratories, and Oak Ridge National Laboratory). Once Documents 1 and 2 are submitted to the regulatory agencies, and characterization requirements for RH-TRU waste are finalized, DOE will produce one document combining all regulatory requirements to guide generator sites in the development of their characterization programs. Each site-specific RH-TRU waste characterization plan will undergo audits by DOE, EPA, and NMED before the beginning of shipments to WIPP. The new characterization requirements will be combined in a revised version of the waste acceptance criteria incorporating changes to allow RH-TRU waste in WIPP.

4.1 DOE’s Considerations in Composing the Characterization Plan

According to the information gathered, several factors played a role in DOE’s approach to the characterization of RH-TRU waste, such as: DOE’s mission to safely dispose of radioactive waste; WIPP’s regulations; federal and state laws and agreements; and DOE’s internal drivers to improve the National Transuranic Waste Management Program. The list of considerations, expanded below, is not in hierarchical order and may not be complete.

One of DOE’s missions is to safely dispose of radioactive waste, including RH-TRU waste, generated during defense-related activities (DOE-EM, 2002a). To this end, DOE is seeking authorization to dispose of RH-TRU waste stored at 13 sites across the country in WIPP. The proposed characterization plan must meet the requirements in the EPA Certification and RCRA Permit (the latter issued by NMED). Besides strict regulatory requirements, DOE is also taking into account non-technical considerations to maintain an effective working relationship with the regulatory agencies, in particular NMED.

DOE and its RH-TRU waste generator sites must also meet sites’ cleanup milestones, set forth by DOE’s compliance agreements with EPA and generator states’ regulators, such as Federal Facility Compliance Agreements and Tri-Party Agreements.



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Characterization of Remote-Handled Transuranic Waste for the Waste Isolation Pilot Plant: Final Report 4 Department of Energy’s Proposed Characterization Plan This chapter describes DOE’s proposed characterization plan for RH-TRU waste. Because the plan must address EPA and NMED regulatory requirements, the characterization plan consists of two documents: a notification of proposed change to the EPA Certification (Document 1) and a Request for RCRA permit modification (Document 2). On June 28, 2002 DOE submitted Documents 1 and 2 to the respective agencies. This chapter addresses the March 2002 draft characterization plan and the main differences with the July 2001 draft. It is the committee’s understanding that DOE will submit to EPA and NMED, along with Documents 1 and 2, a sample of completed characterization documents for three RH-TRU generator sites (Energy Technology Engineering Center, Battelle Columbus Laboratories, and Oak Ridge National Laboratory). Once Documents 1 and 2 are submitted to the regulatory agencies, and characterization requirements for RH-TRU waste are finalized, DOE will produce one document combining all regulatory requirements to guide generator sites in the development of their characterization programs. Each site-specific RH-TRU waste characterization plan will undergo audits by DOE, EPA, and NMED before the beginning of shipments to WIPP. The new characterization requirements will be combined in a revised version of the waste acceptance criteria incorporating changes to allow RH-TRU waste in WIPP. 4.1 DOE’s Considerations in Composing the Characterization Plan According to the information gathered, several factors played a role in DOE’s approach to the characterization of RH-TRU waste, such as: DOE’s mission to safely dispose of radioactive waste; WIPP’s regulations; federal and state laws and agreements; and DOE’s internal drivers to improve the National Transuranic Waste Management Program. The list of considerations, expanded below, is not in hierarchical order and may not be complete. One of DOE’s missions is to safely dispose of radioactive waste, including RH-TRU waste, generated during defense-related activities (DOE-EM, 2002a). To this end, DOE is seeking authorization to dispose of RH-TRU waste stored at 13 sites across the country in WIPP. The proposed characterization plan must meet the requirements in the EPA Certification and RCRA Permit (the latter issued by NMED). Besides strict regulatory requirements, DOE is also taking into account non-technical considerations to maintain an effective working relationship with the regulatory agencies, in particular NMED. DOE and its RH-TRU waste generator sites must also meet sites’ cleanup milestones, set forth by DOE’s compliance agreements with EPA and generator states’ regulators, such as Federal Facility Compliance Agreements and Tri-Party Agreements.

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Characterization of Remote-Handled Transuranic Waste for the Waste Isolation Pilot Plant: Final Report DOE is also required to comply with Title 10 of the Code of Federal Regulations Part 835, which instructs DOE to apply the ALARA principle to protect workers’ health and safety in every DOE facility (10 CFR 835). ALARA (as low as is reasonably achievable), as defined by the Nuclear Regulatory Commission, requires that a reasonable effort be made to keep workers radiation exposures as far below the regulatory dose limit1 as is practical. Moreover, DOE must ensure that all waste is managed in a manner that is protective of worker and public health and safety, and the environment, as specified in DOE’s Order 435.1. Timeliness and cost of cleanup are two internal DOE drivers. A “Top-to-Bottom” review report on DOE’s Office of Environmental Management, which manages the cleanup of all defense-related radioactive waste, recommended adopting an accelerated risk-based cleanup strategy across the DOE complex. The following is an excerpt from this report: “National security will be improved through the consolidation of all special nuclear materials in modern safeguarded facilities and through accelerated disposal of transuranic (TRU) waste currently stored at sites around the country (page IV-1) […] [A] limited amount of TRU waste is highly radioactive and must be handled remotely. Efforts to dispose of these materials in WIPP will be accelerated (page IV-2). […] [T]here are thousands of TRU waste drums stored in above-ground EM facilities that require high-priority funding for safety and security. While most of these storage facilities are inexpensive to maintain, there are dozens of them across the complex, so the cumulative annual fixed cost is significant. Certification and disposal of TRU waste are major cost drivers for the EM program. Efforts to expedite shipments to the Waste Isolation Pilot Plant (WIPP) and streamline regulatory procedures would result in obvious cost savings” (page V-13) (DOE-EM, 2002b). In its WIPP Disposal Phase Final Environmental Impact Statement, DOE estimated the life-cycle cost of the treatment facilities for RH-TRU waste to be $2.94 billion. This corresponds to 15 percent of the total cost of the $19 billion WIPP Project (DOE-CAO, 1997; Volume 5; pages 5–10). DOE also stated in the same reference that the life-cycle cost of the treatment facilities for all the CH- and RH-TRU waste was $11.8 Billion, or 62 percent of the total cost of the WIPP Project. Although these estimates may be outdated, they still demonstrate the magnitude of the characterization costs for TRU waste, in particular for RH-TRU waste. 4.2 DOE’s Goal: A Performance-Based Characterization Plan Given the above considerations, DOE’s stated goal is to adopt a “performance-based” approach to characterize RH-TRU waste. Although Documents 1 and 2 do not provide a definition of a “performance-based characterization plan,” the committee found the following definition in EPA’s Compliance Application Review Document No. 24: “DOE must provide waste inventory information for use in the performance assessment, including the radionuclide content of waste and the physical and 1   The Nuclear Regulatory Commission’s limits for radiation doses to workers are established in Title 10 CFR Part 20 (10 CFR 20.1003).

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Characterization of Remote-Handled Transuranic Waste for the Waste Isolation Pilot Plant: Final Report chemical components that may affect disposal system performance” (EPA, 1998; pages 21–1). EPA defines a “waste characteristic” as “a property of the waste that has an impact on the containment of waste in the disposal system” (40 CFR 194.2). The committee interprets “performance-based characterization plan” as a plan requiring only that information needed to ensure repository integrity, protection of the environment, and health and safety of the public and workers while keeping in consideration tradeoffs between greater characterization accuracy and worker risks. While the characterization requirements to be addressed are the same, this proposed performance-based approach is quite different from the approach used for CH-TRU waste characterization, as explained later in this chapter. The rationale for this different approach relies on the differences in volume and isotopic inventory of RH-TRU waste compared to CH-TRU waste (see Chapter 2). To evaluate the impact of RH-TRU waste on the performance of WIPP, the Sandia National Laboratories performed two performance assessment calculations. In these calculations, the effects of the inventories of CH- and RH-TRU waste are decoupled and several bounding scenarios for RH-TRU waste parameters are used. Documents 1 and 2 include two impact assessments: one for the impact of the radiological parameters of RH-TRU waste and one for the non-radiological parameters listed in the EPA Certification. The Sandia impact analyses showed that radioisotope, free liquids, cellulosics, plastics, rubber, and ferrous metal content in the RH-TRU waste inventory have a negligible impact on repository performance. This is due to the smaller volume and the different radiological composition of the RH-TRU waste inventory compared to the CH-TRU waste inventory projected in WIPP. These performance assessment calculations use the same mathematical models and input parameters used in the compliance certification application (see Chapter 3, Section 3.2.1). The result of the calculations shows that the characterization of waste material parameter weights (e.g., ferrous metals, cellulosics, plastic, and rubber) and the amount of free liquid for RH-TRU waste can be assumed to be as high as the bounding values and still result in WIPP compliance. The bounding values for RH-TRU waste parameters are the same as those used for EPA Certification. The Sandia impact analyses also show that if all the total (both TRU and non-TRU) activity in RH-TRU waste were due to plutonium-239, there would be only a negligible performance impact on WIPP. Therefore, from a performance point of view, waste characterization activities to quantify the above waste parameters could be unnecessary. Even though the impact of RH-TRU waste parameters on the performance of WIPP is negligible, DOE is proposing to collect all the waste information requested in the EPA Certification and RCRA Permit using AK as the primary method of compliance. When AK is not complete or not available, additional compliance methods can be applied to a representative portion of the waste. In contrast to the approach used for CH-TRU waste, this plan does not recommend making measurements for the sole purpose of confirming AK or other measurements unless such confirmation is needed to qualify the AK characterization information (DOE-CBFO, 2002a; page 22). 4.2.1. Acceptable Knowledge The heart of DOE’s proposed performance-based characterization plan is the use of AK to collect the necessary information about a waste stream. DOE plans to use two types of AK: one based on historical information of existing waste, which the committee

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Characterization of Remote-Handled Transuranic Waste for the Waste Isolation Pilot Plant: Final Report terms “historical AK” and which is the most widespread interpretation of AK (see Sidebar 2.1), and one based on new information collected during waste generation or packaging. Historical AK may include administrative, procurement, and quality control documentation associated with the generating process, or past sampling and analytical data. Elements of process knowledge may include information about the process used to generate the waste, material inputs to the process, and the time period during which the waste was generated. Acceptable knowledge is applied on a waste stream basis and may be supplemented with sampling and measurement programs or container-by-container measurements. DOE also considers AK newly generated characterization information, as described in Document 1: “[F]or the RH-TRU waste characterization program, 95 [percent] of the waste will be packaged or repackaged during its preparation for shipment to the WIPP. Information collected under these packaging and repackaging programs is also considered to be AK information. This allows the same AK procedure and guidance to be used in assembling historic AK information or compiling new AK information” (DOE-CBFO, 2002a; Attachment B; page 23). As shown above, DOE’s rationale for proposing AK as the major compliance tool is based on the analysis of the RH-TRU waste inventory. According to the information gathered, 95 percent of RH-TRU waste will either be generated or packaged. This waste will be visually examined during repackaging operations and undergo physical and chemical characterization (for instance, through radiography or radiochemistry) during waste generation and packaging. Based upon EPA’s requirements set forth in 40 CFR 194.22(b), existing information collected before an approved quality assurance program is in place must be qualified for use as AK. Title 40 CFR 194.22(b) lists four methods that may be used individually or in combination to qualify such data: 1) peer review, 2) use of corroborative evidence, 3) confirmation by measurements, or 4) qualification of previous quality assurance programs. DOE is proposing to limit confirmatory measurements only to those cases where historical records are incomplete. DOE proposes not to confirm the newly generated information for 95 percent of the waste since this information will be collected under a certified quality assurance characterization program. The specific needs for waste analysis are described in DOE’s proposed characterization plan as data quality objectives and quality assurance objectives. 4.3 Data Quality Objectives and Quality Assurance Objectives Data quality objectives are proposed by the implementer, in this case DOE, to define what information is necessary to characterize waste. They are qualitative and quantitative statements that clarify program’s objectives, define appropriate types of data, and specify tolerable decision error rates that will be used as the basis for establishing the quality and quantity of data needed to support decisions. The EPA document SW-846 “Test Methods for Evaluating Solid Waste Physical/Chemical Methods” defines data quality objectives as: “Data quality objectives…for the data collection activity describe the overall level of uncertainty that a decision-maker is willing to accept in results derived from environmental data” (EPA, 2002; pages 1–2).

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Characterization of Remote-Handled Transuranic Waste for the Waste Isolation Pilot Plant: Final Report Quality assurance objectives establish minimum requirements for the measurement and representation of data. Quality assurance objectives are designed to provide information that will satisfy the data quality objectives. They correspond to EPA’s “measurement quality objectives.” The elements of the quality assurance objectives are: Data accuracy: the degree to which data agree with an accepted reference or true value. Data precision: a measure of the mutual agreement between comparable data gathered or developed under similar conditions expressed in terms of a standard deviation. Data representativeness: the degree to which data accurately and precisely represent a characteristic of a population, a parameter, variations at a sampling point, or environmental conditions. Data completeness: a measure of the amount of valid data obtained compared to the amount that was expected. Data comparability: a measure of the confidence with which one data set can be compared to another [40 CFR 194.22(c)]. Documents 1 and 2 describe the data quality objectives and quality assurance objectives to meet the requirements in WIPP’s EPA Certification and RCRA Permit, respectively. 4.4 DOE’s Proposed Characterization Plan to Address EPA Requirements The characterization requirements in the EPA Certification, addressing also the requirements in the Land Withdrawal Act, are described in Chapter 3. The data quality objectives, characterization, and implementation methods to address these requirements are provided in Document 1 and summarized in Table 4.1. The characterization methods to meet EPA requirements are the following: Acceptable Knowledge: the type of information used to define waste streams is described in Sidebar 2.1. For the RH-TRU waste characterization program, 95 percent of the waste will be packaged or repackaged during its preparation for shipment to the WIPP. Information collected under these packaging and repackaging programs is considered to be AK information along with historical data. Dose-to-Curie Conversion: the curie content of waste is based on a dose rate measurement taken with a calibrated field instrument. The dose rate measurement is associated with documented isotopic distributions in the waste through the use of empirically developed conversion factors. Dose-to-curie estimates may also be based on the measurement of an indicator activity (e.g., cesium-137) and correlation of other radionuclides by isotopic conversion factors. This method requires good knowledge of the isotopic distribution in the waste. Visual Examination: this method involves the removal of items from the container and their inspection and identification. The examination will be recorded on a signed data form accompanied by visual evidence such as an audio or video tape. Visual examination only provides a visual image of the content of waste containers. It does not provide any information on the isotopic composition of waste. Radiography: this method involves the use of penetrating radiation to investigate the contents of containers. The examination will be recorded on a signed data form

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Characterization of Remote-Handled Transuranic Waste for the Waste Isolation Pilot Plant: Final Report accompanied by visual evidence such as an audio or video tape or other media. Radiography only provides an image of the content of waste containers. It does not provide any information on the isotopic composition of waste. Characterization at the Time of Packaging: this method involves visual examination and other characterization methods applied as waste is packaged for shipment to WIPP. DOE distinguishes this method from visual examination for the following reasons: it applies to 100 percent of the waste in the waste stream; it generally focuses on the development or collection of AK information as opposed to the confirmation of such information; it applies to waste that is not in its final shipping container; and it may require the use of other characterization methods (i.e., AK, visual examination, or radiography) to determine the contents of smaller containers that cannot be readily characterized without testing.2 Direct Assay: this method involves using radioassay systems that are qualified for CH-TRU waste characterization. Counting containers: this method involves automatically counting containers to maintain the record of the amount of metals introduced in the repository. 4.5 DOE’s Proposed Characterization Plan to Address NMED Requirements The characterization requirements in the current RCRA Permit are described in Chapter 3. The proposed data quality objectives and characterization methods to address these characterization requirements are presented in Document 2 and summarized in Table 4.2. Characterization methods and the relative quality assurance objectives of precision, accuracy, representativeness, completeness, and comparability are discussed in Attachment R of Document 2. The same characterization methods have been discussed for Document 1 (see above). Radiography, along with other non-destructive examination and non-destructive assay methods, is also briefly described in Appendix G. 2   The committee observes that “characterization at the time of packaging” may cause a semantic confusion with AK, which is usually associated with historical information. Characterization at the time of packaging generates new information through visual examination, radiography, or other characterization methods; it may also include historical data on a particular waste stream.

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Characterization of Remote-Handled Transuranic Waste for the Waste Isolation Pilot Plant: Final Report TABLE 4.1 DOE’s Data Quality Objectives, Characterization and Implementation Methods to Address EPA Requirements No. Data Quality Objectives Characterization Method Implementation Methods 1 Account for TRU activity. Rationale: This requirement is related to the LWA’s definition of TRU waste and to 40 CFR 191. The purpose for this data quality objective is twofold: 1) ensure that waste is TRU (TRU activity equal to or greater than 100 nanocuries per gram of waste); and 2) determine the plutonium-239 content to satisfy the release limits set forth in 40 CFR 191. 1. AK method 2. Dose to curie 3. Direct assay 4. Characterization at the time of packaging1 Use AK to determine the relationship of TRU activity to total activity (see no. 6 below) for each waste stream (confirmation unnecessary). AK must include TRU information (sufficient to demonstrate the waste stream concentration exceeds 100 nanocuries per gram), or the waste stream value must be established by sampling and measurement, or the TRU activity must be measured for each container. 2 Ensure that waste is of defense origin. Rationale: The LWA allows only disposal of defense-related transuranic waste in WIPP. 1. AK method Use AK to determine whether waste was generated in a defense-related activity. 3 Ensure waste is RH (surface dose equal to or greater than 200 mrem per hour). Rationale: operational requirement to determine handling and characterization requirements. 1. Standard industry survey methods 2. Characterization at the time of packaging Use standard industry survey methods to measure and report surface dose rate. Survey instrument calibrations must be traceable by the National Institute of Standards and Technology. 4 Account for total activity. Rationale: this requirement comes from the LWA limit of 5.1 million curie of total activity for RH-TRU waste. 1. AK method 2. Dose to curie 3. Direct assay 4. Characterization at the time of packaging Use AK to determine total activity of the waste stream (confirmation unnecessary), or establish a waste stream value by sampling and measurement, or measure the total activity of each container. 5 Limit canister activity to less than 23 curies per liter. Rationale: this requirement comes from the LWA limit on canister activity. 1. AK method 2. Dose to curie 3. Direct assay 4. Characterization at the time of packaging Use AK to evaluate each waste stream and show that this limit cannot feasibly be approached for that particular waste stream. For the rare exception where AK indicates that 23 curies per liter is hypothetically feasible, measurements of Total Activity should be obtained on few representative containers to establish a waste stream value, or a site may choose to measure the total activity of each container.

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Characterization of Remote-Handled Transuranic Waste for the Waste Isolation Pilot Plant: Final Report 6 Limit surface dose rate of each container to less than 1,000 rem per hour. Rationale: This is a LWA requirement. 1. Standard industry survey methods 2. Characterization at the time of packaging Survey instrument calibrations must be traceable by the National Institute of Standards and Technology. 7 Limit WIPP inventory to 5 percent by volume of canisters with a dose rate greater than 100 rem per hour. Rationale: This is a LWA requirement. 1. Standard industry survey methods 2. Characterization at the time of packaging Use standard industry survey methods to measure and report Surface Dose Rate. Survey instrument calibrations should be traceable by the National Institute of Standards and Technology. 8 Account for ferrous and non-ferrous metals. Rationale: this is a requirement introduced in the EPA’s Certification. 1. Count containers WWIS [WIPP Waste Information System] electronically counts waste containers. Confirmation unnecessary. 9 Account for cellulosics, plastics, rubber. Rationale: this is a requirement introduced in the EPA Certification 1. AK method 2. Visual examination 3. Characterization at the time of packaging Use AK to determine Summary Category Group (SCG) of each waste stream. Use generator/storage site SCG designation from site documents. WWIS electronically calculates and assigns for each emplaced container (0 for homogenous solids and soils/gravel, and 50 percent of container weight for debris). Confirmation unnecessary if AK information is complete. 10 Account for free water (up to 1 percent of free water by volume). Rationale: WIPP was certified on the basis of a performance calculation using 1 percent of water by volume in the waste. This limit originates from a transportation requirement. 1. AK method 2. NDE such as Radiography 3. Visual examination 4. Characterization at the time of packaging If AK documents the use of liquid management procedures (e.g., removal or absorption), or a process that precludes liquids (e.g., material input records or thermal treatment), then assign 0 percent of liquid by volume for each waste stream. Otherwise assign 1 percent volume to the entire waste stream. Confirmation unnecessary. When AK is lacking, use a non-destructive examination, visual examination, or characterization at the time of packaging on a sampling basis to show that a waste stream contains less than one percent residual liquids. NOTE: AK=acceptable knowledge; LWA=Land Withdrawal Act, NDE=non-destructive examination. Information in this table is presented in Document 1 and supplemented with additional information provided to the committee. 1Characterization at the time of packaging is defined in Document 1 as a characterization method. However, this encompasses several activities, such as visual examination, chemical assays, as explained in the description of characterization methods. SOURCE: DOE (DOE-CBFO, 2002a; 2002c).

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Characterization of Remote-Handled Transuranic Waste for the Waste Isolation Pilot Plant: Final Report TABLE 4.2 DOE’s Data Quality Objectives, Characterization and Implementation Methods to Address NMED Requirements No. Data Quality Objectives Characterization Method Implementation Method 1 Assign hazardous waste codes. Rationale: RCRA requirement as it applies to WIPP. 1. AK method 2. Tests on waste samples Use AK to delineate waste streams, assign hazardous waste codes and summary category groups (SCG) to waste streams, and assign individual containers to waste streams. Use generator/storage site records of container assignments to the waste stream. Confirmation unnecessary. If AK is insufficient, perform tests on a representative (10 percent) sample of the waste. 2 Identify Physical Form. Rationale: RCRA requirement as it applies to WIPP. 1. AK method 2. Visual examination 3. NDE such as radiography Summary category groups define the physical form of the waste as solidified solids (SCG=S3000), soil/gravel (SCG=S4000), or debris (SCG=S5000). Confirmation is unnecessary. If AK is insufficient, perform tests such as VE and NDE on a representative (10 percent) sample of the waste. 3 Limit residual liquids to less than 1 percent volume of RH canister (or drum for 160B). Rationale: residual liquids limit arises from transportation and operational safety considerations. Note that the rationale is different from that in Table 4.1 item 10. Residual liquids are a prohibited item in the current RCRA Permit. 1. AK method 2. Visual examination 3. NDE such as radiography Use AK to demonstrate that the waste stream does not contain residual liquid, or that individual containers contain less than 1 percent by volume of residual liquid (confirmation unnecessary), or sample and NDE/VE to determine the waste stream does not contain residual liquid, or NDE/VE each container in a waste stream. AK must document the use of liquid management procedures (e.g., removal or absorption), or a process that precludes liquids (e.g., material input records or thermal treatment), or there must be a record for each container indicating less than 1 percent by volume of residual liquid, or NDE/VE of a few representative containers (10 percent1) from the waste stream can show the absence of residual liquids, or every container must undergo NDE/VE. 4 Limit residual polychlorinated biphenyls to less than 50 ppm. Rationale: polychlorinated biphenyls are a prohibited item in RCRA Permit if present in a concentration greater than or equal to 50 ppm. 1. AK method 2. Visual examination 3. NDE such as radiography Use AK to determine the absence of possible sources of polychlorinated biphenyls such as transformer oil. If AK is insufficient, perform tests such as VE and NDE on a representative (10 percent) sample of the waste. VE and NDE are used, for instance, to look for parts of or entire transformers. 5 Exclude additional prohibited items Use EPA hazardous waste Additional prohibited items listed in the RCRA Permit (see

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Characterization of Remote-Handled Transuranic Waste for the Waste Isolation Pilot Plant: Final Report   (such as pyrophorics, incompatible chemicals, explosives, compressed gases, ignitable, corrosive, and/or reactive wastes). Rationale: these items are prohibited in the current RCRA Permit. codes Chapter 3) are addressed by the EPA hazardous waste codes assigned to an RH-TRU waste stream. RH-TRU waste containing any one of these items would have EPA hazardous waste codes that would disqualify it from management, storage, and disposal under the WIPP Part A requirements. 6 Identify and quantify volatile organic compounds. Rationale: any waste container that does not have volatile organic compounds concentrations reported for the headspace is currently a prohibited item in the RCRA Permit. No volatile organic compounds measurement proposed on RH-TRU waste. Use bounding analysis for RH-TRU waste contribution to reduce current RCRA Permit Room Limits. NOTE: AK=acceptable knowledge; NDE/VE=non-destructive and visual examination (see Appendix G); VE=visual examination. Information in this table is presented in Document 2 and supplemented with additional information provided to the committee. 1See committee’s Finding 2A, Example #6 in Chapter 5. Other elements of this table are also discussed in Chapter 5. SOURCE: DOE (DOE-CBFO, 2002b; 2002c).

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Characterization of Remote-Handled Transuranic Waste for the Waste Isolation Pilot Plant: Final Report 4.6 Major Differences Between the July 2001 and the March 2002 Drafts As noted in Chapter 1, the committee reviewed two drafts of the proposed characterization plan. This section outlines the five major differences between the two drafts, as follows: Change in the approach to the determination of prohibited items in Document 2. The determination of the absence of all the prohibited items listed in the RCRA Permit was part of the requirements in the July 2001 draft of Document 2 (DOE-CBFO, 2001b; Item 2; pages 2–27). In the March 2002 draft, the only prohibited items explicitly listed as data quality objectives are residual liquids (if more than 1 percent by volume of waste) and polychlorinated biphenyls (if equal to or greater than 50 ppm). Remaining incompatible prohibited items (ignitable, corrosive, reactive, pyrophoric and incompatible waste, explosives, and compressed gases) will be addressed by excluding from shipment hazardous waste with codes corresponding to ignitable (D001), corrosive (D002), and reactive waste (D003). Pyrophoric materials, explosives and compressed gases fall under the definition of reactive waste (D003). Other waste prohibited in WIPP, such as explosives and compressed gases, can be excluded through hazardous waste code screening because any material whose code does not appear in the list of hazardous waste codes allowed in WIPP cannot be shipped. This drives the determination of the remaining prohibited items from a container-by-container basis to a waste stream level, where hazardous waste code assignment decisions are typically made. The hazardous waste code(s) determination will be accomplished using AK. According to DOE, the 1 percent free liquid criterion was retained as a RCRA operational compliance consideration rather than for performance reasons (see Appendix D). Definition of a representative sample of containers to perform additional tests when AK is insufficient. The March 2002 draft defines for the first time a representative sample as “at least 10 percent of the samples,” selected by the generator site (DOE-CBFO, 2002a; Attachment B; page 26). The committee discusses the issue of 10 percent representative sample size in Chapter 5, Finding 2A, Example #6. Change of quality assurance objective to determine the total activity of waste by direct assay. The July 2001 draft of Document 1 read: “Track the RH-TRU waste total activity inventory by the quantification of total activity for a unit (waste stream or individual container) within a factor of five of the true value with a confidence level of 95 percent” (DOE-CBFO, 2001a; Attachment A; page 10). In the March 2002 draft of Document 1, this quality assurance objective was replaced by the quality assurance objective used for CH-TRU waste (DOE-CBFO, 1999b, Appendix A). Moreover, each site will demonstrate the ability of its direct assay measurement system to meet the criteria but will not be subject to the CH-TRU waste performance demonstration program. Distinction between visual examination and characterization at the time of packaging. Most of the RH-TRU waste will either be generated or repackaged. DOE makes a distinction between the characterization at the time of packaging and visual examination (DOE-CBFO, 2002a; Attachment B; pages 26 and 29). The rationale for the distinction is given above (see also the definition of the method “characterization at the time of packaging” in Section 4.4).

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Characterization of Remote-Handled Transuranic Waste for the Waste Isolation Pilot Plant: Final Report More detailed description of characterization requirements and RH-TRU waste inventory in both documents. The March 2002 draft reports data quality objectives and quality assurance objectives for both EPA and RCRA Permit requirements. The documents also present additional information about generator sites and RH-TRU waste inventories. While CH- and RH-TRU waste share the same characterization requirements described in WIPP’s RCRA Permit and EPA Certification, DOE’s approach to meet these requirements for RH-TRU waste is quite different from the way the are met for CH-TRU waste, as explained below. 4.7 Comparison Between the CH- and RH-TRU Waste Characterization Plans The CH-TRU waste characterization plan approved by EPA and NMED is described in Appendix F. Briefly, the characterization plan for CH-TRU waste is based on a 100 percent confirmation of AK information collected on each waste stream. Confirmation is accomplished by radioassay, headspace gas sampling, radiography, or visual examination. For homogeneous wastes,3 this includes taking core samples of a fraction of waste containers prior to their shipment to WIPP. For debris wastes, a 100 percent confirmation program (with headspace gas and radiography determinations for RCRA compliance, and non-destructive assay and radiography determinations for EPA’s compliance) was negotiated between DOE and NMED. Rather than proposing the same approach as for CH-TRU waste, DOE proposes a “performance-based” approach to characterize RH-TRU waste because of the high radiation fields and the negligible impact of this waste on the performance of the repository. The most significant difference between the CH- and the proposed RH-TRU waste characterization plans is that the latter does not require confirmatory testing, sampling, or analysis on 100 percent of containers and allows radiography and visual examination only on a representative selection of containers. DOE proposes to use AK whenever possible to accumulate the information on RH-TRU waste and to perform confirmation measurements only when the information collected on the waste stream is not qualified as AK. The rationale provided by DOE in Document 2 relies on the 95 percent of RH-TRU waste volume that is to be generated or repackaged. Instead of confirming AK, generator sites must provide assurances that the waste is adequately characterized at the time of packaging. On the basis of the Sandia impact analyses, DOE determined that the proposed RH-TRU characterization plan does not require the determination of material parameter category weights and headspace gas analysis, whereas they are required in the CH-TRU waste characterization plan. Instead, DOE proposes to use bounding values for these parameters for RH-TRU waste. Concerning the WIPP’s limit on volatile organic compound emissions, the characterization plan for CH-TRU waste requires tracking individual waste container headspace gas concentrations, which are determined by headspace gas sampling and analysis of CH-TRU waste containers. There is no characterization objective for a direct measurement of the headspace gases in the proposed RH-TRU waste characterization plan because canisters will be located in the walls of the disposal rooms behind shield plugs. Calculations have shown 3   Homogeneous waste is one of the “Summary Category Groups” that indicate the final form of the waste. Homogeneous waste is waste consisting of one main constituent (for instance, sludge) as opposed to the other two category groups: soils and gravel, and debris waste.

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Characterization of Remote-Handled Transuranic Waste for the Waste Isolation Pilot Plant: Final Report that it is possible to account for volatile organic compounds emission rates from RH-TRU waste indirectly.4 This is accomplished by conservatively incorporating the maximum potential volatile organic compounds contribution from RH-TRU waste in the maximum allowable volatile organic compounds emission limits established by the RCRA Permit (Spangler et al., 2002). 4   To the best of committee’s knowledge, experiments on volatile organic compound emissions from RH-TRU waste have not been conducted.