U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office – Environmental Management Nevada Test Site Low- Level Radioactive Waste Disposal Operations Stephen Mellington, Assistant Manager for Environmental Management June 7, 2006 National Governor’s Association
U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office – Environmental Management U.S. Department of Energy, National Nuclear.
Apr 02, 2015
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U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office – Environmental Management
U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office – Environmental Management
Nevada Test Site Low-Level Radioactive Waste Disposal
Operations
Stephen Mellington, Assistant Managerfor Environmental Management
June 7, 2006National Governor’s Association
Page 2
79FY06 – 06/07/2006
• Approximately 1,375 square miles of federally owned and controlled land – surrounded by approximately 4,500 square miles of federally owned and controlled land
• Located approximately 65 miles northwest of Las Vegas, Nevada
The Nevada Test Site (NTS)
Page 3
79FY06 – 06/07/2006
U.S. Department of Energy Site Comparisons
Page 4
79FY06 – 06/07/2006
Arid desert climateAverage 4-6 inches annual precipitationEvaporation exceeds rainfall by 12 times
Depth to groundwater for disposal areasArea 3 – 1,600 feet (488 meters)Area 5 – 770 feet (235 meters)
Thick alluvial basinsNegligible recharge
Groundwater from past cooler/wetter climateNo “fast” pathways
Environmental Conditions
No significant surface waterNo permanent streams or lakes
Many closed basins
Page 5
79FY06 – 06/07/2006
Historic Activities at the NTS
• First NTS atmospheric nuclear test detonated on January 27, 1951
• 928 atmospheric and underground nuclear tests conducted between 1951 and 1992
• Nuclear weapons development and testing generated radioactive waste
Page 6
79FY06 – 06/07/2006
Early Disposal Activities
• Low-level radioactive waste (LLW) first collected for disposal at an Area 5 site in 1953
• LLW first disposed in Area 5 Sugar Bunker trench in 1961
• LLW first disposed in Area 3 subsidence crater in 1968
• Began accepting LLW generated by other U.S. Department of Energy sites in 1976
• Formal LLW disposal project established in 1978
Page 7
79FY06 – 06/07/2006
Area 5Radioactive Waste Management Site
• Developed around the original Sugar Bunker trench
• 732 acres available for disposal – 140 acres currently used
• Disposal cells are excavated pits and trenches
• Eight (8) active disposal cells (21 closed and two constructed/available)
Page 8
79FY06 – 06/07/2006
• Diverse radioactive waste streams and package types handled– Asbestos– Contact-handled LLW
monoliths (in excess of 90,000 pounds each)
– High-concentration thorium– Remote-handled LLW
monoliths– Roll-off intermodals– Thorium nitrate– Mixed LLW
Area 5Radioactive Waste Management Site
(continued)
Page 9
79FY06 – 06/07/2006
Area 3Radioactive Waste Management Site
• Encompasses 120 acres
• Five (5) disposal cells (comprised of 7 subsidence craters)
• Radioactive waste managed includes LLW and Mixed LLW (cell closed)
• Subsidence craters from historic underground nuclear testing are used as disposal cells
Page 10
79FY06 – 06/07/2006
Mixed LLW at the Nevada Test Site
• 1987: Mixed LLW disposal begins
• 1990: State of Nevada requires the U.S. Department of Energy to provide a Waste Analysis/Verification Plan
– Disposal of off-site generated Mixed LLW is halted
Page 11
79FY06 – 06/07/2006
Mixed LLW at the Nevada Test Site (continued)
• 2000: DOE issues Waste Management Programmatic Environmental Impact Statement Record of Decision declaring the Nevada Test Site as a regional disposal site for LLW and Mixed LLW
• 2000-2005: DOE works with State to resolve technical issues affecting the acceptance of off-site Mixed LLW
• December 2005: State issues Nevada Test Site Resource Conservation and Recovery Act (RCRA) Part B Permit – lifting the off-site Mixed LLW disposal prohibition
Page 12
79FY06 – 06/07/2006
Graphic Number:
/454/PICT0089.JPG
Photo Date:
4/11/2006
Mixed LLW at the Nevada Test Site (continued)
• April 11, 2006: Received first off-site MLLW shipment since 1990
U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office – Environmental Management
U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office – Environmental Management
Disposal Practices
Page 14
79FY06 – 06/07/2006
NTS Requirements / Capabilities
• U.S. Department of Energy Order 435.1
• NTS Waste Acceptance Criteria (NTSWAC)
• Category 2 non-reactor nuclear facility
– Documented safety analyses
– Technical safety requirements
• All disposed waste containers are retrievable
– Grid coordinate tracking system for performance modeling and retrievability
Page 15
79FY06 – 06/07/2006
Tailored Disposal Cells and Waste Forms• Unique waste streams of LLW require specialized
disposal cells– High-dose LLW– Non-standard waste packaging– Radon flux requirements– Classified materials
• Cells are designed and constructed prior to acceptance/receipt of waste on an as-needed basis
• Crane placement and heavy equipment requirements considered
• Approximately 200,000 cubic yards of soil moved each year to create custom disposal cells
Page 16
79FY06 – 06/07/2006
Area 5 Disposal Cells –Waste Container Configuration
Boxes containing LLW are placed in a stair-stacked
configuration within a engineered grid
Page 17
79FY06 – 06/07/2006
Area 5 Disposal Cells –Waste Container Configuration (continued)
LLW drums are positioned in a single layer with boxes of LLW
arranged as “book ends”
Page 18
79FY06 – 06/07/2006
Area 5 Disposal Cells –Waste Container Configuration
(continued)
Remote-Handled Monoliths – 10 Rem/hour dose rates and higher
97 high-dose LLW monoliths (~20 R/hr) were received with a cumulative dose of 0.38178 man-Rem for 900 man-hours
Monoliths were “nested” in between LLW cargo containers arranged in
an H-pattern
Page 19
79FY06 – 06/07/2006
Site Differences
• Area 3 Radioactive Waste Management Site located 15 miles northwest of Area 5
• Area 3 historically used for larger, bulk radioactive waste packages
• Layer-cake geometry used to dispose radioactive waste in Area 3
Page 20
79FY06 – 06/07/2006
Area 3 Disposal Cells –Waste Container Configuration (continued)
Cargo containers of LLW
Page 21
79FY06 – 06/07/2006
Area 3 Disposal Cells –Waste Container Configuration (continued)
Bulk equipment such as nozzles, compressors, converters, centrifuges, etc.
Page 22
79FY06 – 06/07/200630 generators are currently approved to ship LLW to the NTS
General Atomics
NTS Approved LLW Generators
Page 23
79FY06 – 06/07/2006
Mixed LLW Generators
Mound
WVDP
SRS
BNLLLNL
INL
SNL
Lexington
Paducah
Portsmouth
Perma-Fix
Oak Ridge(2)
Current
Potential
Page 24
79FY06 – 06/07/2006
NTS LLW Disposal History
0
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
1980-1989*
1990-1999*
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
ForecastActual On-siteActual Off-site
Vo
lum
e (1
,000
ft3 )
1,67
4
Fiscal Year
2,42
2
FY 2003 (total) – 3,239,726 ft3
FY 2004 (total) – 3,743,572 ft3
FY 2005 (total) – 2,091,771 ft3
FY 2006 (total received as of 5/21/2006) – 790,933 ft3
*Indicates average per year for that decade
520
930
1,44
0 sh
ipm
ents
2,43
4
705
Page 25
79FY06 – 06/07/2006
NSO Commitment
• NSO is committed to supporting accelerated cleanup by providing disposal services to all U.S. Department of Energy sites
• NSO is committed to reducing risk to NTS workers, the public, and the environment with timely, cost-effective disposal services
• NSO is committed to working cooperatively with regulators and keeping the public informed of its Environmental Management activities through the Community Advisory Board
U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office – Environmental Management
U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office – Environmental Management
Groundwater
Page 27
79FY06 – 06/07/2006
Background Information• 1951 to 1992: United States
Government conducted 828 underground nuclear tests at the Nevada Test Site (NTS) at depths ranging from approximately 90 to 4,800 feet below the ground surface
• About one-third of these tests occurred near or below the water table, which resulted in some contamination of the area’s groundwater
Page 28
79FY06 – 06/07/2006
Addressing Groundwater Contamination
• U.S. Department of Energy began preliminary hydrologic research in the 1970s
• A more intensive groundwater studies program was launched in 1989 with the formation of the Groundwater Characterization Project at the Department of Energy Nevada Site Office
Page 29
79FY06 – 06/07/2006
Addressing Groundwater Contamination (continued)
• The Underground Test Area (UGTA) sub-project evaluates the historic testing impacts on groundwater resources and study the extent of contaminant migration
• The scope includes collection of multiple sources of field data in order to create a 3-D computer model
– This model includes groundwater, flow and transport parameters
• The models will be used to help create a monitoring network to ensure that the public/workers are not exposed to groundwater exceeding Safe Drink Water Act standards
Page 30
79FY06 – 06/07/2006
UGTA Strategy• Drill wells, analyze existing wells, and
conduct geophysical studies to collect data
• Evaluated the NTS on a regional scale – separated areas hydrologically and geographically into five (5) manageable Corrective Action Units
• Develop phased approach – Phase I and Phase II each representing stages of data collection and analysis
• Identify contaminant movement and develop contaminant boundaries
• Implement recommendations provided by an independent peer review of the strategy
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