Ensure a Secure and Sustainable Energy Future
Basin-scale Density-dependent Groundwater flow Near a Salt
RepositoryKristopher L. KuhlmanSandia National Laboratories
Anke Schneider Gesellschaft fr Anlagen- und
Reaktorsicherheit
Washington, DCSeptember 7-9, 2016
Sandia National Laboratories is a multi-mission laboratory
managed and operated by Sandia Corporation, a wholly owned
subsidiary of Lockheed Martin Corporation, for the U.S. Department
of Energys National Nuclear Security Administration under contract
DE-AC04-94AL85000. SAND2016-8647 C
1
OutlineGeologic/Hydrologic Background2016 progressSNLGRSSummary
of issuesGoals moving forward
2
WIPP HydrogeologyRepository in Salado bedded salt
formation>500-m thick salt unitHydrogeology of formations above
saltRustler FormationCulebra dolomiteMagenta
dolomiteAnhydriteMudstone/HaliteDewey Lake Red BedsSilt/sand stones
+ clayDockum GroupSilt/sand stones + clay
3
Rustler Conceptual Model4
West(Nash Draw)EastWest of WIPPShallow unitsHigh
permeabilityRelatively fresh waterEast of WIPPDeeper unitsLow
permeabilitySaturated brineRegional groundwaterFlow used in WIPP
PALong-term geological stability of salt
Corbet (2000) WIPP Model5Most of Delaware BasinTransient
SimulationClimate variation (dry vs. wet)14,000 y present 10,000
yModel Implementationwater table moving boundary model~8700 km2
region (78 km 112 km)Coarse mesh (2 km square cells)12 model layers
(10 geo layers)1,500 cells/layer~18,000 elements total
Motivation6Benchmark against existing solution (Corbet,
2000)Comparison with original modelOld mesh, model parameters &
boundary conditionsInclude new processes, features &
dataInclude density-driven flow (e.g., Davies, 1989)Include
chemistry & mineral dissolutionInvestigate flow & chemistry
boundary conditionsTest and update hydrogeological conceptual
modelIncoporate current data: 81Kr GW age data, water level
dataComparison and Development of Models PFLOTRAN (SNL)Add density
dependent flowd3f (GRS)
SNL Progress in 20167
SNL PFLOTRAN version8
Corbet (2000): Hydraulic conductivity [m/s]PFLOTRAN:
Permeability [m2]
SNL PFLOTRAN version9
~25x vertical exaggeration
SNL PFLOTRAN version10
Original Mesh: 13-layer hexahedral (cuboid) elements (18,000
elements)100x vertical exaggeration
SNL PFLOTRAN model11
Without density dependence or chemistry
SNL PFLOTRAN model12
GRS Progress in 201613
SNL: data of basin-scale groundwater model after Corbet &
Knupp 1996raster data of 10 hydrogelogic units Basin-scale model
df++14
df++
source: SNL, SECOFL3D
df++ model
Dewey Lake/TriassicAnhydrite 5Mudstone/Halite 4Anhydrite
4Magenta DolomiteAnhydrite 3Mudstone/Halite 3Anhydrite 2Culebra
DolomiteLos Medanos Member110 km 500 m
N 6,000 km
15
df++ model
Dewey Lake/TriassicAnhydrite 5Mudstone/Halite 4Anhydrite
4Magenta DolomiteAnhydrite 3Mudstone/Halite 3Anhydrite 2Culebra
DolomiteLos Medanos Member110 km 500 m
N 6,000 km16
anisotropic grid refinementadapt multigrid operators
df++ prism grid
N
source: Corbet 2000last year: 2,614,000 tetrahedrons (coarse
grid)now: 54,228 prisms (coarse grid) 18,000 hexahedrons
SECOFL3D17
Dewey Lake/TriassicAnhydrite 5Mudstone/Halite 4Anhydrite
4Magenta DolomiteAnhydrite 3Mudstone/Halite 3Anhydrite 2Culebra
DolomiteLos Medanos Member
Free Water Table levelset method
18model domain D (const.)phreatic surface represented by a
levelset function
partially saturated zone (not solved here)
fully saturated zone (Darcys law)
groundwater table (moving boundary)(t)(t)D\(t)
DP. Frolkovi: Application of level set method for groundwater
flow with moving boundary, Adv. Wat. Res. 2012
signed distance function
effective flow velocity / groundwater distance velocity
18
Free Water Table levelset method
19model domain D (const.)phreatic surface represented by a
levelset function
partially saturated zone (not solved here)
fully saturated zone (Darcys law)
groundwater table (moving boundary)(t)(t)D\(t)
DP. Frolkovi: Application of level set method for groundwater
flow with moving boundary, Adv. Wat. Res. 2012
signed distance function
effective flow velocity / groundwater distance velocity
19
Initial & Boundary Conditions
Nc=1(saturated brine)recharge 2.0 0.1 mm/year, c=0 /
seepageinitial condition: water table 14,000 years agosource:
Corbet &Knupp 199620
closed boundaries
salt concentration
df++ 2016 Simulationsdensity-driven flow, free water tablegrid
level 1 (217 000 prisms) and level 2 (900 000 prisms)21velocity
water table
df++ 2016
Current work:new BMWi-funded project GRUSS (April 2016)improve
robustness of solvers (convergence, timesteps)implement volume of
fluid (VOF) method to speed-up free surface handling
22
Summary of Issues / Path Forward23
Issues Encountered24
Schedule25SECOFL3D data provided by SNLGRS begins building d3f
modelSNL begins building PFLOTRAN modelSNL consults
GRS builds d3f model equivalent to Corbet (2000)SNL builds
PFLOTRAN equivalent to Corbet (2000)GRS includes density-driven
flow
SNL includes density-driven flow to PFLOTRANIncluding new
features / dataUpdate boundary conditionsUpdate hydrological
implementation and conceptual modelInclude geochemical tracers
Year 1Year 2Year n