Publications Details
Brine inflow sensitivity study for Waste Isolation Pilot Plant boreholes: Results of one-dimensional simulations
Brine inflow to the Waste Isolation Pilot Plant is important in assessing the performance of the repository, and a mechanistic model is needed for performance calculations. Brine inflow experiments are being conducted, and formation parameters such as the permeability and diffusivity are inferred from these data using a simplified one-dimensional radial, uniform property, single-phase Darcy flow model. This model has met with limited success in interpreting some of the recent data. Much of the data could not be satisfactorily fit with the above model because the brine inflow rate increases with time, so a more mechanistic model is being developed based on the TOUGH and TOUGH2 computer codes. These codes are much more complex than the simplified model and include a number of parameters that have not been measured. Therefore, a one-dimensional brine inflow sensitivity study has been undertaken to evaluate the importance of a number of these parameters in influencing the behavior of brine inflow to open boreholes. In addition, two-phase conditions have been included in the study, and the sensitivity of gas inflow rates and the formation pressure and saturation distributions after 1 year are examined. These results should be helpful in determining what additional measurements are necessary to assist in the development of a more mechanistic brine inflow model.