|
Items in cart [1] |
Questions? Call 888-624-8373 |
| Copyright © 2009. National Academy of Sciences. All rights reserved. Terms of Use and Privacy Statement |
Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter.
Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 110
OCR for page 111
OCR for page 112
OCR for page 113
OCR for page 114
114
Improving the Characterization Program for Contact-Handled Transuranic Waste
TRU waste at the Savannah River Site indicates considerable variability in
Americium-241 activity (DOE-FENS, 1997~. The isotopic mix varies substantially from
year to year; from 1970 to 1995, waste streams at the site had Americium-241 activity
ranging from zero to 546 curies. Waste retrieval and packaging for shipment to WIPP
involve the entire inventory, (i.e., drums and culverts are selected for characterization
without consideration of isotopic mix).
r
E.4 Case Study: Rocky Flats Environmental Technology Site
Rocky Flats Environmental Technology Site has had more experience than any
other site in the processing and management of TRU waste. This site sent the first
shipment of CH-TRU waste to WIPP on June 16, 1999. As of December 2003, more
than 1,000 shipments have been made from Rocky Flats to WIPP. Rocky Flats is in the
terminal phase of its operations and it is projected that the facility will complete waste
processing and shipments by 2006.
Plutonium "pits" used in the manufacture of nuclear weapons were produced at
the Rocky Flats Environmental Technology Site. Consequently, most of the Rocky Fiats
waste consists of waste contaminated with Plutonium-239. Plutonium is an alpha emitter
and produces significant neutron dose rates when the alpha particles interact with low-
atomic-number elements in the waste. There is also a gamma-ray component to the
container surface dose rate due to the presence of Americium-241.
High-temperature processing was one of the steps involved in the production of
plutonium pits. Therefore, DOE negotiated with the New Mexico Environment
Department, an exemption from the headspace gas sampling and analysis requirement
for some of the Rocky Flats Environmental Technology Site TRU waste, because
thermally treated waste cannot contain any residual volatile organic compound (see
Chapter 3~. Some of the TRU waste at the Rocky Flats Environmental Technology Site
was also solidified in a cement matrix.
In 1992, nuclear weapons-related production was halted at Rocky Flats, and
DOE began the processes of decontamination and decommissioning of buildings and
environmental restoration. A very large amount of alpha-contaminated gIoveboxes,
piping, fluoride salts, equipment, and scrap material had to be processed for packaging
and shipment, in addition to a substantial amount of contaminated soil in the surrounding
areas.
E.4.1 Workers closes and risks from operations
In 2002, 215 persons (including waste handlers, on-site transporters, and others
Involved in drum processing) were monitored. Of these, 205 had measurable exposures.
The collective dose to all monitored persons was 36,800 person-millirem for 2002. The
average surface dose rate for processed containers is 6.57 mrem per hour.
Workers at the Rocky Flats Environmental Technoloov Site have an orcler-of-
magnitude higher exposure than those at Savannah River Site, although it is still small
relative to permissible limits. The increased worker exposures are due to handling and
processing containers with significantly higher surface dose rates. Retrieving drums of
approved waste from storage locations at the Rocky Flats Environmental Technology
Site required moving non-approved waste drums out of the way to allow access to the
desired drum (the so-called dance of the drums, see Section 4.6~. With operational
experience, less time is expended looking for a single drum, and the cirum mining and
moving operations have been minimized (DOE-CABE, 2003~.
Drum handling and processing experience and use of best available practices
have resulted in significant reductions in personnel exposures. Radiation exposure
received by personnel in the shipping facilities at the Rocky Flats Environmental
OCR for page 115
Representative terms from entire chapter:
flats environmental
Appendix E Health and Safety Issues
115
Technology Site (Buildings 440 and 664) has been used to document trends in
personnel dose related to WIPP operations. In 2000 the cumulative dose per shipment
was 250 mrem; in 2003 the cumulative dose per shipment was reduced to 50 mrem. The
information gathered on the Rocky Flats site indicates that streamlining the
characterization process can have a beneficial impact on worker doses (Spears, 2003~.
Surface dose rates from drums originating from the Rocky Flats Environmental
Technology Site average approximately ~ mrem per hour (about 100 of the 19,000
drums emplaced at WIPP had surface dose rates in excess of ~ 0 mrem per hour).
, . ,
..... ..
References
DOE-CABE (U.S. Department of Energy-Center for Acquisition and Business
Excellence). 2003. WIPP TRU Characterization Cost Analysis. May 1. Final Draft.
National Energy Technology Laboratory. Morgantown, W.Va.
DOE-FSElS (DOE-Final Supplemental Environmental Impact Statement). 1997. Waste
Isolation Pilot Plant Disposal Phase Final Supplemental Environmental Impact
Statement. September. DOE/ElS-0026-S-2. CarIsbad, N.Mex.
DOE-SRS (DOE-Savannah River Site). 2003a. Solid Waste Management Facility:
Facility Overview for National Academy of Sciences. Document provided to the
Committee on Optimizing the Characterization and Transportation of Transuranic
Waste Destined for the Waste Isolation Pilot Plant, Augusta, Gal, March 4.
DOE-SRS. 2003b. TRU Waste Characterization Dose Estimate. Document provided to
the Committee on Optimizing the Characterization and Transportation of Transuranic
Waste Destined for the Waste Isolation Pilot Plant, Augusta, Gal, March 4.
EEG (Environmental Evaluation Group). ~990. Risk Analysis of the Transport of Contact
Handled Transuranic (CH-TRU) Wastes to WIPP along Selected Highway Routes in
New Mexico Using RADTRAN IV. A. F. Gallenos and J. K. Channell. EEG-46.
-
Albuquerque, N. Mex. Available at: .
EEG. 1999. A Comparison of the Risks from the Hazardous Waste and Radioactive
Waste Portions of WIPP Inventory. J. K. Channell and R. H. Neill. EEG-72.
Albuquerque, N.Mex. Available at: .
McCulia, W. H., and G. D. Van Soest. 2003. Analysis of Volatile Organic Compound
Levels in the Transuranic Waste Inventory. LANL-EES-12. September 4 Draft. Los
Alamos, N.Mex.
Nelson, R. A. 2003. What's in WIPP? Four Years Radioactive Waste Disposal, Three
Years Hazardous Waste Disposal. Presentation to the Committee on Optimizing the
Characterization and Transportation of Transuranic Waste Destined for the Waste
Isolation Pilot Plant, Santa Fe, N.Mex., January 27.
NRC (National Research Councit). 1990. Health Effects of Exposure to Low Levels of
ionizing Radiation: BEIR V. National Academy Press. Washington, D.C. Available at:
