| Issue |
Source |
PMR Approach |
| 6. |
Develop a comprehensive, high-resolution groundwater flow model and render it compatible with all relevant site and basin-wide hydrologic and hydrogeologic data. Make the horizontal and vertical spatial resolutions of this model much greater than those of present site and regional flow models, especially in and downstream of the Yucca Mountain area, and coordinate its development with that of a similar-scale model recently constructed for environmental management of the Nevada Test Site. |
|
CRWMS M&O 1998b
[summaries, Neuman] |
Site-scale SZ flow and transport 3-D finite element model developed; evolution of model discussed in Section 2; improvements to TSPA-VA model discussed in Section 2.5. Model validation now includes comparisons of: permeability data to calibrated permeability values, fluxes from regional model with fluxes from calibrated model, measured upward gradient with predicted upward gradient, hydrochemical data with calculated particle pathways, and natural analogs. These activities and process model uncertainties are discussed in Section 3.4. |
| 7. |
Quantify the uncertainty of all input data into the above model and include reliable prior information, especially that concerning hydraulic parameters from large-scale pumping tests, formally in its calibration. A model that encompasses the entire basin has better-defined boundary inflows and outflows than does a site model that has artificial boundaries, and is therefore better suited for calculation and calibration of water balance. |
|
CRWMS M&O 1998b
[summaries, Neuman] |
Model validation now includes comparisons of: permeability data to calibrated permeability values, fluxes from regional model with fluxes from calibrated model, measured upward gradient with predicted upward gradient, hydrochemical data with calculated particle pathways, and natural analogs. These activities and process model uncertainties are discussed in Section 3.4. |
| 8. |
To further improve the prospects of constructing and calibrating a meaningful regional flow model, strengthen the isotope hydrology program of the Yucca Mountain Project to obtain more extensive and reliable information about groundwater ages and directions of flow throughout the basin. |
|
CRWMS M&O 1998b
[summaries, Neuman] |
Geochemistry Analysis and Model Report (CRWMS M&O 2000m) discusses hydrochemistry in detail and provides evaluation of groundwater ages and confirmation of flow paths; Section 3.1.3.1 discusses spatial patterns of groundwater chemistry. Model validation now includes comparisons of: permeability data to calibrated permeability values, fluxes from regional model with fluxes from calibrated model, measured upward gradient with predicted upward gradient, hydrochemical data with calculated particle pathways, and natural analogs. These activities and process model uncertainties are discussed in Section 3.4. |
| 9. |
Drill an additional borehole strategically into the large hydraulic gradient area, then log and sample it thoroughly enough to confirm or deny that the large hydraulic gradient is an artifact of perched conditions, as some propose. |
|
CRWMS M&O 1998b
[summaries, Neuman] |
Borehole WT-24 drilled in large hydraulic gradient area and indicates that the large hydraulic gradient is, in part, due to perching. The large hydraulic gradient is discussed in Sections 3.2.2.3 and 3.2.5.1. |