Hydrologic calculations to evaluate backfilling shafts and drifts for a prospective nuclear waste repository in unsaturated tuff

Technical Report · Sat Jun 01 04:00:00 EDT 1985

OSTI ID:59593

Freshley, M D; Dove, F H; Fernandez, J A

As part of the Nevada Nuclear Waste Storage Investigations, preliminary hydrologic calculations were performed to determine if choice of drift backfill could influence water flow past waste packages adjacent to a repository drift in unsaturated volcanic tuff. Additional calculations were performed to determine if water would flow into a shaft that penetrates a nonwelded-welded tuff interface. These hydrologic calculations consisted of numerical simulations using the computer code TRUST. Idealized configurations of a vertical shaft extending to the repository and a repository drift with horizontal and vertical emplacement of waste packages were evaluated. Both fine-grained and coarse-grained materials were considered as backfill to the drift and shaft. In the numerical simulations, coarse-grained backfill material drained more completely than fine-grained material and formed a more effective capillary barrier to water flow. Although the magnitude of flow in the modeled regions is small, selection of backfill was shown to influence flow through the repository drift and vertical shaft. However, it is concluded that selection of backfill does not significantly influence water flow past vertically or horizontally emplaced waste packages.

• Research Organization: Pacific Northwest Lab., Richland, WA (United States); Sandia National Labs., Albuquerque, NM (United States)
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 59593
• Report Number(s): SAND--83-2465; PNL--5117; ON: DE86000050
• Country of Publication: United States
• Language: English

Related Subjects

05 NUCLEAR FUELS
58 GEOSCIENCES
BACKFILLING
COMPUTERIZED SIMULATION
FLOW MODELS
FLUID FLOW
HYDROLOGY
SHAFT EXCAVATIONS
TUFF
YUCCA MOUNTAIN
Yucca Mountain Project