U.S. Department of Energy logoU.S. DOE Carlsbad Field Office, WIPP - Waste Isolation Pilot Plant... a critical step toward solving the nuclear waste disposal problem.

Home |   News & Information   |   Document Center |    Transportation  |   Opportunities  |   Contacts  |  Links |  Search


1.0 RH-TRU Waste Introduction


The Waste Isolation Pilot Plant (WIPP) Land Withdrawal Act (LWA), Public Law 102-579, requires that a study be conducted of remote-handled (RH) transuranic (TRU) waste prior to initial receipt of waste in WIPP. In addition, the DOE considers the study to be a prudent exercise in the compliance certification process of the WIPP repository. The specific project requirements for the RH-TRU waste study are addressed in the LWA, Section 6(c)(2)(B) under the WIPP test phase activities. As specified in the law, the RH-TRU waste study shall include an analysis of the impact of RH-TRU waste on the performance assessment (PA) of the WIPP and a comparison of RH-TRU waste with CH-TRU waste.

1.1 Objectives

The objectives of this study include:

  • Conducting an analysis of the impacts of RH-TRU wastes on the PA of the repository to determine the effects of RH-TRU waste as a part of the total WIPP disposal inventory; and
  • Conducting a comparison of CH-TRU and RH-TRU wastes to assess the differences and similarities for such issues as gas generation, flammability and explosiveness, solubility, and brine and geochemical interactions.

These analyses address the elements of CH-TRU and RH-TRU wastes that are important to an assessment of long-term compliance by WIPP. This study is consistent with the PA process and the method used for the draft compliance certification application submitted to the U.S. Environmental Protection Agency (EPA) in March 1995 [DOE, 1995a]. The waste inventory data used throughout this study represents the best available information as reported by the waste generator/storage sites.

1.2 Background

The U.S. Department of Energy (DOE) and its parent Federal agencies have designed, developed, tested, and manufactured nuclear weapons for nearly 50 years. One of the by-products of these defense activities is waste that contains TRU elements. The primary types of operations that generate TRU wastes include production of weapons, plutonium (Pu) recovery, research and development programs, and decontamination and decommissioning activities. TRU wastes are defined by DOE Order 5820.2A [DOE, 1988] as wastes that are contaminated with radionuclides that exhibit the following characteristics:

  • An atomic number greater than 92.
  • Alpha-emitting transuranium radionuclides with half-lives greater than 20 years.
  • Exist in the waste at concentrations greater than 100 nanocuries per gram (nCi/g) for any single waste package.

TRU waste is also classified according to its measured radiation level at the external surface of the waste package. Most TRU wastes (approximately 95 percent of the WIPP inventory by volume) emit primarily alpha radiation. Alpha particles are readily absorbed and lose energy on collisions; therefore, they do not represent an external radiation hazard but threaten internal tissues if inhaled or ingested. Because even the relatively low levels of beta and gamma radiation at the surfaces of CH-TRU waste containers are potentially harmful to workers, WIPP waste-handling procedures are designed to minimize worker exposure to the CH-TRU waste drums. In addition, CH-TRU waste packages are limited to a container surface dose of 200 millirems per hour (mrem/hr).

TRU wastes that have a measured radiation dose rate greater than 200 mrem/hr are classified as RH-TRU wastes (up to 1,000 rem/hr). These wastes contain larger quantities of radionuclides that emit beta and gamma as well as alpha radiation. RH-TRU waste will be handled by remote methods to provide the necessary shielding to ensure worker safety during disposal. The WIPP facility is fully equipped to handle RH-TRU waste and its associated radiation. Each RH-TRU shipping cask, which will contain one canister, will be inspected and removed from the transport vehicles and transferred to the unloading room where the canisters will be removed and placed in the "hot cell." After inspection, the canister will be positioned in the transfer cell, loaded into a heavily shielded facility cask, and lowered underground through the waste shaft for emplacement. The facility cask will be transported to the disposal location and the canister emplaced with the facility cask held in position to provide adequate shielding at all times.

In 1992, the 102nd Congress enacted the WIPP LWA, Public Law 102-579, to withdraw the WIPP land-use area (16 square miles) from "entry, appropriation, and disposal" and to reserve the land for authorized WIPP-related activities. Jurisdiction over the WIPP land-use area was transferred from the Secretary of Interior to the Secretary of Energy. The Act also established the requirements for initiating the test phase activities and the limitations on test phase activities and established the regulatory structure for the certification by the Administrator of the EPA "whether the WIPP facility will comply with the final disposal regulations." The test phase activities and requirements focused on the proposed experiments to be conducted at WIPP using actual CH-TRU wastes from TRU waste generator/storage sites. Development of a Test Phase Plan was required to set forth the proposed test phase activities, as well as to specify the quantities of wastes needed for experimentation, to describe how the tests would provide relevant data to support a certification of compliance, and to include the necessary justification for all such activities.

The LWA also includes several restrictions on actual waste experiments at WIPP, including prohibiting the use of RH-TRU wastes during the test phase. In lieu of conducting experiments with RH-TRU wastes, the LWA includes requirements for DOE to conduct a study to analyze the impacts of RH-TRU wastes on performance of the repository. This requirement was included to ensure that the characteristics of RH-TRU wastes are considered in the long-term performance evaluations. In addition, the DOE considers the development of the RH-TRU Waste Study to be a prudent exercise in the certification process of the WIPP repository.

The specific requirements established in the LWA are stated below.

Land Withdrawal Act, Section 6(c)(2)(B)

(B)Study.

  1. In general. Within 3 years after the date of the enactment of this Act, the Secretary shall complete a study on remote-handled transuranic waste in consultation with affected States, the Administrator, and after the solicitation of views of other interested parties.
  2. Requirements of study. Such study shall include an analysis of the impact of remote-handled transuranic waste on the performance assessment of WIPP and a comparison of remote-handled transuranic wastes with contact-handled transuranic waste on such issues as gas generation, flammability, explosiveness, solubility, and brine and geochemical interactions.
  3. Publication. The Secretary shall publish the findings of such study in the Federal Register.

[Public Law 102-579, 1992]

To initiate consultations as required under Section 6(c)(2)(B)(i) of the LWA, the DOE/Carlsbad Area Office (CAO) distributed the Implementation Plan for the Remote Handled TRU Waste Performance Assessment and Comparison to Contact Handled TRU Waste (hereafter referred to as the Implementation Plan) [DOE, 1995b] in January 1995 for review and comment. Comments received on the Implementation Plan were considered in the development of this document. The Implementation Plan discussed the outline and anticipated technical approach to be used for this RH study. A presentation to the public and stakeholder organizations was given April 7, 1995 [DOE, 1995c] to solicit input regarding the development of the study. This study has been provided to stakeholders and the EPA for review and comment prior to final publication. The WIPP Land Withdrawal Act (Public Law 102-579) Section 6(c)(2)(B)(ii) is the basis of this document and is addressed in Chapters 3 and 4. Chapter 3 compares CH-TRU and RH-TRU wastes with respect to the LWA issues, while Chapter 4 evaluates the impact that RH-TRU waste has on PA.

Continue to Section 2
Return to Table of Contents


[   Home  |   News & Information  |   Document Center  |   Transportation  |   Opportunities  |   Contacts  |   Links  |   Search  ]

Notice To Users:

Use of this system constitutes consent to security monitoring and testing. All activity is logged with your host name and IP address.

Privacy

Have a question about WIPP?

Contact the WIPP Information Center at
1-800-336-9477 or email us at:
infocntr@wipp.ws

webmaster@wipp.ws